Background Intramuscular fat is an important factor in evaluating pork quality and varies widely among different pig breeds.However,the regulatory mechanism of circular RNAs(circRNAs)in lipid metabolism remains largel...Background Intramuscular fat is an important factor in evaluating pork quality and varies widely among different pig breeds.However,the regulatory mechanism of circular RNAs(circRNAs)in lipid metabolism remains largely unexplored.Results We combined circRNA-seq and Ribo-seq data to screen a total of 18 circRNA candidates with coding potential,and circANKRD17 was found to be significantly elevated in the longissimus dorsi muscle of Lantang piglets,with a length of 1,844 nucleotides.Using single-cell sequencing,we identified 477 differentially expressed genes in IMF cells between Lantang and Landrace piglets,with enrichment in the PPAR signaling pathway.These genes included FABP4,FABP5,CPT1A,and UBC,consistent with the high levels of acylcarnitines observed in the longissimus dorsi muscles of the Lantang breed,as determined by lipidomic analysis.Further in vitro and in vivo experiments indicated that circANKRD17 can regulate lipid metabolism through various mechanisms involving the PPAR pathway,including promoting adipocyte differentiation,fatty acid transport and metabolism,triglyceride synthesis,and lipid droplet formation and maturation.In addition,we discovered that circANKRD17 has an open reading frame and can be translated into a novel 571-amino-acid protein that promotes lipid metabolism.Conclusions Our research provides new insights into the role of protein-coding circANKRD17,especially concerning the metabolic characteristics of pig breeds with higher intramuscular fat content.展开更多
Chicken meat quality directly influences consumer acceptability and is crucial for the economic success of the poultry industry.Genetics and nutrition are key determinants of the meat quality traits in broilers.This r...Chicken meat quality directly influences consumer acceptability and is crucial for the economic success of the poultry industry.Genetics and nutrition are key determinants of the meat quality traits in broilers.This review summarizes the research advances in this field,with a focus on the genetic and nutritional foundations that regulate intramuscular fat(IMF)deposition and meat quality in chickens over the past decade.The effects of embryonic nutrition,both maternal nutrition and in ovo feeding(IOF),on skeletal muscle development,the IMF content,and meat quality traits in broilers are also discussed.In genetics,single-cell RNA sequencing revealed that de novo lipogenesis predominantly occurs in myocytes,which is key to the formation of IMF in chicken muscle tissue.Fatty acid synthase(FASN)is the key enzyme involved in this process.This discovery has reshaped the traditional understanding of intramuscular lipid metabolism in poultry.Key genes,proteins,and pathways,such as FASN,FABP4,PPARG,C/EBPα,SLC27A1;LPL,APOA1,COL1A1;PPAR and ECM–receptor interactions signaling,have been identified to regulate IMF content and distribution by modulating fatty acid metabolism and adipogenesis.LncHLFF was innovatively found to promote ectopic IMF deposition in chickens via exosome-mediated mechanisms without affecting abdominal fat deposition.MiR-27b-3p and miR-128-3p were found to inhibit adipogenic differentiation by targeting PPARG,thereby affecting IMF formation.In nutrition,nutrigenomics research has shown that fructose enhances IMF deposition by activating ChREBP,providing new targets for nutritional interventions.Adjusting dietary components,including energy,protein,amino acids,fatty acids,and phytochemicals(e.g.,rutin),has been shown to significantly improve meat quality in broilers.Maternal nutrition(e.g.,intake of energy,amino acids,vitamins,and trace elements)and IOF(e.g.,N-carbamylglutamate)have also been confirmed to significantly impact offspring meat quality,opening new avenues for improving embryonic nutrition.Based on these significant advancements,this review proposes strategies that integrate genetic and nutritional approaches.These strategies aim to modulate the differentiation fate of paraxial mesenchymal stem cells toward myogenic or adipogenic lineages and the interaction between muscle and adipose tissues.These insights would help to improve meat quality while ensuring the growth performance of broiler chickens.展开更多
Background Chinese indigenous pigs are popular with consumers for their juiciness,flavour and meat quality,but they have lower meat production.Insulin-like growth factor 2(IGF2) is a maternally imprinted growth factor...Background Chinese indigenous pigs are popular with consumers for their juiciness,flavour and meat quality,but they have lower meat production.Insulin-like growth factor 2(IGF2) is a maternally imprinted growth factor that promotes skeletal muscle growth by regulating cell proliferation and differentiation.A single nucleotide polymorphism(SNP) within intron 3 of porcine IGF2 disrupts a binding site for the repressor,zinc finger BED-type containing 6(ZBED6),leading to up-regulation of IGF2 and causing major effects on muscle growth,heart size,and backfat thickness.This favorable mutation is common in Western commercial pig populations,but absent in most Chinese indigenous pig breeds.To improve meat production of Chinese indigenous pigs,we used cytosine base editor 3(CBE3)to introduce IGF2 intron3-C3071T mutation into porcine embryonic fibroblasts(PEFs) isolated from a male Liang Guang Small Spotted pig(LGSS),and single-cell clones harboring the desired mutation were selected for somatic cell nuclear transfer(SCNT) to generate the founder line of IGF2^(T/T) pigs.Results We found the heterozygous progeny IGF2^(C/T) pigs exhibited enhanced expression of IGF2,increased lean meat by 18%-36%,enlarged loin muscle area by 3%-17%,improved intramuscular fat(IMF) content by 18%-39%,marbling score by 0.75-1,meat color score by 0.53-1.25,and reduced backfat thickness by 5%-16%.The enhanced accumulation of intramuscular fat in IGF2^(C/T) pigs was identified to be regulated by the PI3K-AKT/AMPK pathway,which activated SREBP1 to promote adipogenesis.Conclusions We demonstrated the introduction of IGF2-intron3-C3071T in Chinese LGSS can improve both meat production and quality,and first identified the regulation of IMF deposition by IGF2 through SREBP1 via the PI3KAKT/AMPK signaling pathways.Our study provides a further understanding of the biological functions of IGF2and an example for improving porcine economic traits through precise base editing.展开更多
Background Pork quality is affected by the type of muscle fibers, which is closely related to meat color, tenderness and juiciness. Exosomes are tiny vesicles with a diameter of approximately 30–150 nm that are secre...Background Pork quality is affected by the type of muscle fibers, which is closely related to meat color, tenderness and juiciness. Exosomes are tiny vesicles with a diameter of approximately 30–150 nm that are secreted by cells and taken up by recipient cells to mediate communication. Exosome-mediated muscle-fat tissue crosstalk is a newly discovered mechanism that may have an important effect on intramuscular fat deposition and with that on meat quality. Various of adipose tissue-derived exosomes have been discovered and identified, but the identification and function of muscle exosomes, especially porcine fast/slow myotube exosomes, remain unclear. Here, we first isolated and identified exosomes secreted from porcine extensor digitorum longus(EDL) and soleus(SOL), which represent fast and slow muscle, respectively, and further explored their effects on lipid accumulation in longissimus dorsi adipocytes.Results Porcine SOL-derived exosomes(SOL-EXO) and EDL-derived exosomes(EDL-EXO) were first identified and their average particle sizes were approximately 84 nm with double-membrane disc-shapes as observed via transmission electron microscopy and scanning electron microscopy. Moreover, the intramuscular fat content of the SOL was greater than that of the EDL at 180 days of age, because SOL intramuscular adipocytes had a stronger lipid-accumulating capacity than those of the EDL. Raman spectral analysis revealed that SOL-EXO protein content was much greater than that of EDL-EXO. Proteomic sequencing identified 72 proteins that were significantly differentially expressed between SOL-EXO and EDL-EXO, 31 of which were downregulated and 41 of which were upregulated in SOL-EXO.Conclusions Our findings suggest that muscle-fat tissue interactions occur partly via SOL-EXO promoting adipogenic activity of intramuscular adipocytes.展开更多
Introduction: Intramuscular depot betamethasone treatment had resulted in a significant improvement among fibromyalgia patients with elevated C-reactive protein (C-RP) levels. Here, we wanted to evaluate the same regi...Introduction: Intramuscular depot betamethasone treatment had resulted in a significant improvement among fibromyalgia patients with elevated C-reactive protein (C-RP) levels. Here, we wanted to evaluate the same regimen of treatment among fibromyalgia patients with normal C-RP levels. These patients represent the overwhelming majority of fibromyalgia patients. Patients and Methods: Consecutive patients with fibromyalgia attending the outpatient rheumatology clinic, with normal C-RP level and negative serology, who had failed different medical treatment, were asked to participate in our study. All patients have qualified the American College of Rheumatology (ACR) criteria from 2010. After consent, patients had an intra-muscular injection of 14 mg depot betamethasone at the gluteal area. Just prior to the injection, 1 week and 1 month later, patients were interviewed by phone and asked to answer the Fibromyalgia Revised Questionnaire (FIQR). Wilcoxon’s signed ranked test was used to compare the results 1 week and 1 month following the injection, compared to the base line scores. Results: Seventeen (17) patients completed the study. Favorable effects were seen regarding 13 out of 19 parameters one week following the injection, including functional parameters, mood and anxiety, tenderness to touch and intolerance to noise and light. No significant favorable effect was seen 1 month following the injection except for one parameter: ability of walking for twenty minutes. Conclusions: IM depot betamethasone injection had very limited and transient favorable effects on fibromyalgia patients with normal C-RP levels. Such a treatment is not a recommended modality of routine treatment, among fibromyalgia patients with normal C-RP levels.展开更多
Twenty-four male Kazak sheep and 30 Xinjiang fine wool sheep at different ages were selected to investigate the development-dependent expression levels of fatty acid synthase （FAS） gene and hormone-sensitive lipase ...Twenty-four male Kazak sheep and 30 Xinjiang fine wool sheep at different ages were selected to investigate the development-dependent expression levels of fatty acid synthase （FAS） gene and hormone-sensitive lipase （HSL） gene in muscle and their effects on the contents of intramuscular fat （IMF）. Longissimus dorsal muscle was sampled to measure IMF and total RNA was extracted to determine FAS and HSL mRNA expression levels by real-time PCR. The results showed that： l） The IMF content increased continuously with growth and showed significant differences （P 〈 0.05） between different age groups in male Kazak sheep, but in Xinjiang fine wool sheep there was no such difference observed. Furthermore, the IMF contents in Kazak were much higher （P 〈 0.01） than that of the other breed from day 30 to 90. 2） FAS mRNA expression level was the highest （P 〈 0.05） on day 0 in Kazak sheep and then declined with growth, in the other breed the gene showed a d‘ecline-rise-decline-rise＇ expression manner as the animals grew. HSL mRNA expression level had a similar model in two breeds, in Kazak sheep it was the highest on day 0 （P 〈 0.05） and in Xinjiang fine wool sheep on day 30 （P 〈 0.01）, then both decreased after this term. 3） In male Kazak sheep, FAS and HSL mRNA expression level were both negatively related to IMF content （r= -0.485 （P = 0.02）, r= -0.423 （P = 0.05））, and the ratio of FAS/HSL expression exhibited significantly negatively related IMF contents. In male Xinjiang sheep, there were no obvious relationship between FAS and HSL expression and IMF content （P 〉 0.05）.展开更多
Eighty-four castrated boars including Laiwu Black （LW） （weight 30-90 kg, n = 6） and Lulai Black （LL） （weight 40-100 kg, n = 6） were used to study the developmental changes of collagen type Ⅲ alpha 1 （Col3al...Eighty-four castrated boars including Laiwu Black （LW） （weight 30-90 kg, n = 6） and Lulai Black （LL） （weight 40-100 kg, n = 6） were used to study the developmental changes of collagen type Ⅲ alpha 1 （Col3al） mRNA expression in the muscle and their association with intramuscular collagen （IMC）. The muscle total RNA was extracted to determine the abundance of Col3al mRNA using relative quantitative RT-PCR with β-actin mRNA as the internal standard. The results indicated that the developmental patterns of muscle Col3al mRNA in LW and LL pigs were similar. The abundance of Col3al mRNA increased with body weight, but decreased a little at 70 kg and 80 kg phases for LW and LL, respectively. On the whole, the expression level of Col3al mRNA in muscle of LW was higher than that of LL （P 〈 0.05）. Correlation analysis showed that the expression of Col3al mRNA in muscle was positively correlated with total and insoluble IMC, but was negatively correlated with IMC solubility for LW pigs （P 〈 0.01） and LL pigs （P 〈 0.05）, respectively. These results suggest that the muscle Col3al gene expression is affected by body weight and genotype and has important effect on IMC content and characteristics.展开更多
Ectopic adiposity has gained considerable attention because of its tight association with metabolic and cardiovascular health in persons with spinal cord injury（SCI）. Ectopic adiposity is characterized by the storag...Ectopic adiposity has gained considerable attention because of its tight association with metabolic and cardiovascular health in persons with spinal cord injury（SCI）. Ectopic adiposity is characterized by the storage of adipose tissue in non-subcutaneous sites. Magnetic resonance imaging（MRI） has proven to be an effective tool in quantifying ectopic adiposity and provides the opportunity to measure different adipose depots including intermuscular adipose tissue（IMAT） and intramuscular adipose tissue（Intra MAT） or intramuscular fat（IMF）. It is highly important to distinguish and clearly define these compartments, because controversy still exists on how to accurately quantify these adipose depots. Investigators have relied on separating muscle from fat pixels based on their characteristic signal intensities. A common technique is plotting a threshold histogram that clearly separates between muscle and fat peaks. The cut-offs to separate between muscle and fat peaks are still not clearly defined and different cut-offs have been identified. This review will outline and compare the Midpoint and Otsu techniques, two methods used to determine the threshold between muscle and fat pixels on T1 weighted MRI. The process of water/fat segmentation using the Dixon method will also be outlined. We are hopeful that this review will trigger more research towards accurately quantifying ectopic adiposity due to its high relevance to cardiometabolic health after SCI.展开更多
During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).Based on the results o...During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).Based on the results of previous studies,other adipose tissue depots(e.g.,perirenal and subcutaneous)develop from the fetal stage primarily as brown adipose tissue.The hyperplastic stage of intramuscular adipose is considered to develop from late pregnancy,but there is no evidence indicating that intramuscular adipose tissue develops initially as brown adipose tissue.Hyperplastic growth of intramuscular adipose continues well into postweaning and is dependent on the timing of the transition to grain-based diets;thereafter,the late-stage development of intramuscular adipose tissue is dominated by hypertrophy.For muscle development,hyperplasia of myoblasts lasts from early(following development of somites in the embryo)to middle pregnancy,after which growth of muscle is the result of hypertrophy of myofibers.Vitamin A is a fat-soluble compound that is required for the normal immunologic function,vision,cellular proliferation,and differentiation.Here we review the roles of vitamin A in intramuscular adipose tissue and muscle development in cattle.Vitamin A regulates both hyperplasia and hypertrophy in in vitro experiments.Vitamin A supplementation at the early stage and restriction at fattening stage generate opposite effects in the beef cattle.Appropriate vitamin A supplementation and restriction strategy increase intramuscular adipose tissue development(i.e.,marbling or intramuscular fat)in some in vivo trials.Besides,hyperplasia and hypertrophy of myoblasts/myotubes were affected by vitamin A treatment in in vitro trials.Additionally,some studies reported an interaction between the alcohol dehydrogenase-1C(ADH1C)genotype and vitamin A feed restriction for the development of marbling and/or intramuscular adipose tissue,which was dependent on the timing and level of vitamin A restriction.Therefore,the feed strategy of vitamin A has the visible impact on the marbling and muscle development in the cattle,which will be helpful to promote the quality of the beef.展开更多
Background: Intramuscular fat(IMF) content is a relevant trait for high-quality meat products such as dry-cured ham,but increasing IMF has the undesirable correlated effect of decreasing lean growth.Thus,there is a ne...Background: Intramuscular fat(IMF) content is a relevant trait for high-quality meat products such as dry-cured ham,but increasing IMF has the undesirable correlated effect of decreasing lean growth.Thus,there is a need to find selection criteria for IMF independent from lean growth.In pigs,the proportion of linoleic(C18:2) and arachidonic(C20:4) acids decline with fat deposition and therefore they can be considered as indicators of fatness.The aim of this research was to estimate the genetic variation for C18:2 and C20:4 in IMF and their genetic correlations with IMF and lean growth traits,with the objective to assess their potential as specific biomarkers of IMF.The analysis was conducted using a full-pedigreed Duroc resource line with 91,448 records of body weight and backfat thickness(BT) at 180 days of age and 1371 records of fatty acid composition in the muscle gluteus medius.Results: The heritability estimates for C18:2 and C20:4 in IMF,whether expressed in absolute(mg/g of muscle) or in relative(mg/g of fatty acid) terms,as well as for their ratio(C20:4/C18:2),were high(> 0.40),revealing that the C18:2 to C20:4 pathway is subjected to substantial genetic influence.Litter effects were not negligible,with values ranging from8% to 15% of the phenotypic variance.The genetic correlations of C18:2 and C20:4 with IMF and BT were negative(-0.75 to-0.66,for IMF,and-0.64 to-0.36,for BT),if expressed in relative values,but almost null(-0.04 to 0.07),if expressed in absolute values,except for C18:2 with IMF,which was highly positive(0.88).The ratio of C20:4 to C18:2 also displayed a stronger genetic correlation with IMF(-0.59) than with BT(-0.10).Conclusions: The amount of C18:2 in muscle can be used as an IMF-specific biomarker.Selection for the absolute amount of C18:2 is expected to deliver a similar response outcome as selection for IMF at restrained BT.Further genetic analysis of the C18:2 metabolic pathway may provide new insights into differential fat deposition among adipose tissues and on candidate genes for molecular markers targeting specifically for one of them.展开更多
Fatty acid composition of neutral lipids （NLs）, phospholipids （PLs） and free fatty acids （FFAs） from intramuscular fat （IMF）, lipid oxidation and lipase activity in muscle Semimembranosus （SM） and msucle Bic...Fatty acid composition of neutral lipids （NLs）, phospholipids （PLs） and free fatty acids （FFAs） from intramuscular fat （IMF）, lipid oxidation and lipase activity in muscle Semimembranosus （SM） and msucle Biceps femoris （BF） of dry-cured Xuanwei ham during the 90-d salting stages were analysed. The salt content increased from 0.34 to 3.52%in BF and from 0.10 to 5.42%in SM during the 90 d salting stage, respectively. PLs of IMF in both BF and SM decreased 54.70%（P〈0.001） and 34.64%（P〈0.05）, furthermore, the saturated fatty acids （SFA）, monounsaturated fatty acids （MUFA） and polyunsaturated fatty acids （PUFA） of PLs in both muscles were hydrolysed almost isochronously. FFAs were increased from 0.46 g 100 g-1 lipids to 2.92 g 100 g-1 lipids in BF at the end of salting, which was lower than SM （from 1.29 g 100 g-1 lipids to 9.70 g 100 g-1 lipids）. The activities of acid lipase, neutral lipase and acid phospholipase all remained active in the 90 d. The thiobarbituric acid reactive substances （TBARS） was slowly increased to 1.34 mg kg-1 muscle in BF and to 2.44 mg kg-1 muscle in SM during the salting stage. In conclusion, the controlled salting process prompted the hydrolysis of PLs of IMF notably and increased the lipid oxidation of muscles within some limits.展开更多
Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a nov...Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a novel miRNA implicated in porcine IMF adipogenesis was found, and its effect and regulatory mechanism were further explored with respect to intramuscular preadipocyte proliferation and differentiation.Results: By porcine adipose tissue miRNA sequencing analysis, we found that miR-146a-5p is a potential regulator of porcine IMF adipogenesis. Further studies showed that miR-146a-5p mimics inhibited porcine intramuscular preadipocyte proliferation and differentiation, while the miR-146a-5p inhibitor promoted cell proliferation and adipogenic differentiation. Mechanistically, miR-146a-5p suppressed cell proliferation by directly targeting SMAD family member 4(SMAD4) to attenuate TGF-β signaling. Moreover, miR-146a-5p inhibited the differentiation of intramuscular preadipocytes by targeting TNF receptor-associated factor 6(TRAF6) to weaken the AKT/mTORC1 signaling downstream of the TRAF6 pathway.Conclusions: MiR-146a-5p targets SMAD4 and TRAF6 to inhibit porcine intramuscular adipogenesis by attenuating TGF-β and AKT/mTORC1 signaling, respectively. These findings provide a novel miRNA biomarker for regulating intramuscular adipogenesis to promote pork quality.展开更多
Pain following depot intramuscular （IM） injection of oil vehicle-based drugs has been little studied. This study aimed to determine prospectively the prevalence,determinants,severity and functional consequences of p...Pain following depot intramuscular （IM） injection of oil vehicle-based drugs has been little studied. This study aimed to determine prospectively the prevalence,determinants,severity and functional consequences of pain during the week after IM injection of 1 000 mg testosterone undecanoate （TU） in a 4-mL castor oil vehicle. Androgendeficient men receiving regular T replacement therapy at an academic andrology clinic were recruited to report pain scores using a coloured visual linear analogue scale at seven times over the first day and daily for a week after a deep IM gluteal injection. The time course and covariables influencing pain scores were analysed by mixed model analysis of variance （ANOVA）. Following 168 injections in 125 men,pain was reported by 80% of men,peaking immediately after injection,reaching only moderate severity,lasting 1-2 days and returning to baseline by day 4.The pain required little analgesic use and produced minimal interference in daily activities. The time course of pain scores was reproducible in the 43 men who underwent two consecutive injections. Pain was more severe in men who had an earlier painful injection,but less severe in older and more obese men. There were negligible differences in post-injection pain experience between experienced nurses administering injections. Deep IM gluteal injection of depot TU in 4-mL castor oil is well tolerated and post-injection pain is influenced by earlier painful injection experience,as well as age and obesity.展开更多
Background Long non-coding RNAs(lncRNAs)regulate numerous biological processes,including adipogenesis.Research on adipogenesis will assist in the treatment of human metabolic diseases and improve meat quality in lives...Background Long non-coding RNAs(lncRNAs)regulate numerous biological processes,including adipogenesis.Research on adipogenesis will assist in the treatment of human metabolic diseases and improve meat quality in livestock,such as the content of intramuscular fat(IMF).However,the significance of lncRNAs in intramuscular adipogenesis remains unclear.This research aimed to reveal the lncRNAs transcriptomic profiles in the process of bovine intramuscular adipogenesis and to identify the lncRNAs involved in the adipogenesis of bovine intramuscular adipocytes.Results In this research,a landscape of lncRNAs was identified with RNA-seq in bovine intramuscular adipocytes at four adipogenesis stages(0 d,3 d,6 d,and 9 d after differentiation).A total of 7035 lncRNAs were detected,including 3396 novel lncRNAs.Based on the results of differential analysis,co-expression analysis,and functional prediction,we focused on the bovine intramuscular adipogenesis-associated long non-coding RNA(BIANCR),a novel lncRNA that may have an important regulatory function.The knockdown of BIANCR inhibited proliferation and promoted apoptosis of intramuscular preadipocytes.Moreover,BIANCR knockdown inhibited intramuscular adipogenesis by regulating the ERK1/2 signaling pathway.Conclusion This study obtained the landscape of lncRNAs during adipogenesis in bovine intramuscular adipocytes.BIANCR plays a crucial role in adipogenesis through the ERK1/2 signaling pathway.The results are noteworthy for improving beef meat quality,molecular breeding,and metabolic disease research.展开更多
Background:Increasing intramuscular fat(IMF)is an important strategy to improve meat quality,but the regulation mechanism of IMF deposition needs to be systematically clarified.Results:A total of 520 chickens from a s...Background:Increasing intramuscular fat(IMF)is an important strategy to improve meat quality,but the regulation mechanism of IMF deposition needs to be systematically clarified.Results:A total of 520 chickens from a selected line with improved IMF content and a control line were used to investigate the biochemical mechanism of IMF deposition in chickens.The results showed that the increased IMF would improve the flavor and tenderness quality of chicken meat.IMF content was mainly determined both by measuring triglyceride(TG)and phospholipid(PLIP)in muscle tissue,but only TG content was found to be decisive for IMF deposition.Furthermore,the increase in major fatty acid(FA)components in IMF is mainly derived from TGs(including C16:0,C16:1,C18:1n9c,and C18:2n6c,etc.),and the inhibition of certain very-long-chain FAs would help to IMF/TG deposition.Conclusions:Our study elucidated the underlying biochemical mechanism of IMF deposition in chicken:Prevalent accumulation of long-chain FAs and inhibitions of medium-chain FAs and very long chain FA would jointly result in the increase of TGs with the FA biosynthesis and cellular uptake ways.Our findings will guide the production of high-quality chicken meat.展开更多
Intramuscular fat （IMF）, an important flavor precursor of porcine meat, is closely related to pork quality traits such as pH, color, tenderness, water-holding capacity （WHC） and juiciness, and thus is one of the i...Intramuscular fat （IMF）, an important flavor precursor of porcine meat, is closely related to pork quality traits such as pH, color, tenderness, water-holding capacity （WHC） and juiciness, and thus is one of the important factors affecting pork quality. Pork IMF content is not only associated with swine breed on heredity, but also influenced by the alteration of nutrients in diet. These may give a possibility for researchers to improve the IMF content and pork quality by their work on swine breed or heredity, and nutrition regulation in diet. Therefore, this article summarizes the effects of swine breed and nutrition regulation on IMF content briefly to provide some information for future researches.展开更多
Intramuscular fat （IMF） is a crucial factor in the quality of chicken meat. The genetic basis underlying it is complex. Follicle-stimulating hormone （FSH）, well-known as an effector in reproductive tissues, was re...Intramuscular fat （IMF） is a crucial factor in the quality of chicken meat. The genetic basis underlying it is complex. Follicle-stimulating hormone （FSH）, well-known as an effector in reproductive tissues, was recently discovered to stimulate abdominal fat accumulation in chicken. The effect of FSH on IMF accumulation and the underlying molecular regulatory mechanisms controlling both IMF and abdominal fat deposition in vivo are largely unknown. In this study, two groups of chickens were treated with chicken FSH or a placebo. The lipid content of breast muscle, abdominal fat volume, and serum concentrations of FSH were examined. Related genes implicated in breast muscle and abdominal fat accumulation were also investigated. Compared to the control group, the triglyceride （TG） content of breast muscle and the percentage of abdominal fat in FSH-treated chickens were significantly increased by 64.9% and 56.5% （P〈0.01）, respectively. The FSH content in the serum of FSH-treated chickens was 2.1 times than that of control chickens （P〈0.01）. Results from quantitative real-time polymerase chain reaction （qRT-PCR） assays showed that relative expression levels of fatty acid synthase （FAS）, lipoprotein lipase （LPL）, diacylglycerol acyltransferase 2 （DGAT2）, adipocyte fatty acid binding protein （A-FABP）, and peroxisome proliferator-activated receptor ~ （PPARy） were significantly upregulated in breast muscle following FSH treatment （P〈0.01）. Treatment with FSH also signifi- cantly increased relative expression levels of FAS, LPL, DGA T2, A-FABP, and PPARy in abdominal fat tissue （P〈0.05） The results of principal component analysis （PCA） for gene expression （breast muscle and abdominal fat） showed that the control and FSH treatment groups were well separated, which indicated the reliability of the data. This study demonstrates that FSH plays an important role in IMF accumulation in female chickens, which likely involves the regulation of biosynthesis genes related to lipid metabolism.展开更多
We report the case of a cervical pregnancy successfully treated with intramuscular injection of methotrexate(MTX) and intramniotic administration of potassium chloride. A 41-year-old woman was admitted to our Departme...We report the case of a cervical pregnancy successfully treated with intramuscular injection of methotrexate(MTX) and intramniotic administration of potassium chloride. A 41-year-old woman was admitted to our Department with the suspicion of ectopic pregnancy. Transvaginal ultrasound revealed empty endometrialcavity, gestational sac within the cervical canal and embryonic echo measuring crown rump length 1.5 mm. Serum beta human chorionic gonadotropine(β-HCG) was measured 28590 IU/L. No cardiac activity was detected. The diagnosis of a cervical pregnancy was made. Patient was treated with intramuscular administration of methotrexate(50 mg/m2) in combination with ultrasoundguided intramniotic injection of KCl(2 meq/mL). Gradual decrease of β-HCG levels as well as ultrasound observation of collapsed gestational sac was observed. No curettage was necessitated. Patient was discharged on day 10 th and was set in follow-up on a weekly basis. β-HCG values were measured < 10 IU/L on 56 th day after MTX administration. Intramuscular administration of MTX may be effective in treatment of cervical pregnancy without additional interventional measures.展开更多
To study the kinetics in vivo of a Hantaan virus DNA vaccine, we constructed a fusion DNA vaccine, pEGFP/S, by cloning the S segment of Hantavirus into the vector, pEGFP-C1, which encodes Green fluorescent protein EGF...To study the kinetics in vivo of a Hantaan virus DNA vaccine, we constructed a fusion DNA vaccine, pEGFP/S, by cloning the S segment of Hantavirus into the vector, pEGFP-C1, which encodes Green fluorescent protein EGFP. In this report, we provide evidence that pEGFP/S was distributed and persistently expressed for more than 60 days in several organs after inoculation. Our findings suggest that the persistent immune responses induced by a Hantaan virus DNA vaccine are likely due to the plasmid pEGFP/S deposited in vivo, which acts as a booster immunization.展开更多
AIM： To compare intradermal （ID） and intramuscular （IM） booster doses, which have been used in healthy and high risk subjects, such as healthcare workers, haemodialysis patients, human immunodeficiency virus pati...AIM： To compare intradermal （ID） and intramuscular （IM） booster doses, which have been used in healthy and high risk subjects, such as healthcare workers, haemodialysis patients, human immunodeficiency virus patients, and renal transplant recipients unresponsive to initial hepatitis B vaccination, in celiac individuals. METHODS： We conducted our study on 58 celiac pa- tients, vaccinated in the first year of life, whose blood analysis had showed the absence of protective hepati- tis B virus （HBV） antibodies. All patients had received the last vaccine injection at least one year before study enrolment and they had been on a gluten free diet for at least 1 year. In all patients we randomly performed an HBV vaccine booster dose by ID or IM route. Thirty celiac patients were revaccinated with recombinant hepatitis B vaccine （Engerix B） 2 μg by the ID route, while 28 celiac patients were revaccinated with Engerix B 10 μg by the IM route. Four weeks after every boost- er dose, the anti-hepatitis B surface （HBs） antibody titer was measured by an enzyme-linked immune- adsorbent assay. We performed a maximum of three booster doses in patients with no anti-HBs antibodies after the first or the second vaccine dose. The cut off value for a negative anti-HBs antibody titer was 10 IU/L.Patients with values between 10 and 100 IU/L were considered ＂low responders＂ while patients with an antibody titer higher than 1000 IU/L were considered ＂high responders＂. RESULTS： No significant difference in age, gender, du- ration of illness, and years of gluten intake was found between the two groups. We found a high percent- age of ＂responders＂ after the first booster dose （ID = 76.7%, IM = 78.6%） and a greater increase after the third dose （ID = 90%, IM = 96.4%） of vaccine in both groups. Mloreover we found a significantly higher num- ber of high responders （with an anti-HBs antibody titer 〉 1000 IU/L） in the ID （40%） than in the IM （7.1%） group, and this difference was evident after the first booster dose of vaccination （P 〈 0.01）. No side effects were recorded in performing delivery of the vaccine by either the ID or IM route. CONCLUSION： Our study suggests that both ID and IM routes are effective and safe options to administer a booster dose of HBV vaccine in celiac patients. Howev- er the ID route seems to achieve a greater number of high responders and to have a better cost/benefit ratio.展开更多
基金supported by the Biological Breeding-Major Projects in National Science and Technology[grant numbers 2023ZD04044]the Natural Science Foundation of China Program[grant numbers 32072714].
文摘Background Intramuscular fat is an important factor in evaluating pork quality and varies widely among different pig breeds.However,the regulatory mechanism of circular RNAs(circRNAs)in lipid metabolism remains largely unexplored.Results We combined circRNA-seq and Ribo-seq data to screen a total of 18 circRNA candidates with coding potential,and circANKRD17 was found to be significantly elevated in the longissimus dorsi muscle of Lantang piglets,with a length of 1,844 nucleotides.Using single-cell sequencing,we identified 477 differentially expressed genes in IMF cells between Lantang and Landrace piglets,with enrichment in the PPAR signaling pathway.These genes included FABP4,FABP5,CPT1A,and UBC,consistent with the high levels of acylcarnitines observed in the longissimus dorsi muscles of the Lantang breed,as determined by lipidomic analysis.Further in vitro and in vivo experiments indicated that circANKRD17 can regulate lipid metabolism through various mechanisms involving the PPAR pathway,including promoting adipocyte differentiation,fatty acid transport and metabolism,triglyceride synthesis,and lipid droplet formation and maturation.In addition,we discovered that circANKRD17 has an open reading frame and can be translated into a novel 571-amino-acid protein that promotes lipid metabolism.Conclusions Our research provides new insights into the role of protein-coding circANKRD17,especially concerning the metabolic characteristics of pig breeds with higher intramuscular fat content.
基金funded by the Regional Innovation and Development Joint Fund of National Natural Science Foundation of China(Project No.U21A20253)2115 Talent Development Program of China Agricultural University.
文摘Chicken meat quality directly influences consumer acceptability and is crucial for the economic success of the poultry industry.Genetics and nutrition are key determinants of the meat quality traits in broilers.This review summarizes the research advances in this field,with a focus on the genetic and nutritional foundations that regulate intramuscular fat(IMF)deposition and meat quality in chickens over the past decade.The effects of embryonic nutrition,both maternal nutrition and in ovo feeding(IOF),on skeletal muscle development,the IMF content,and meat quality traits in broilers are also discussed.In genetics,single-cell RNA sequencing revealed that de novo lipogenesis predominantly occurs in myocytes,which is key to the formation of IMF in chicken muscle tissue.Fatty acid synthase(FASN)is the key enzyme involved in this process.This discovery has reshaped the traditional understanding of intramuscular lipid metabolism in poultry.Key genes,proteins,and pathways,such as FASN,FABP4,PPARG,C/EBPα,SLC27A1;LPL,APOA1,COL1A1;PPAR and ECM–receptor interactions signaling,have been identified to regulate IMF content and distribution by modulating fatty acid metabolism and adipogenesis.LncHLFF was innovatively found to promote ectopic IMF deposition in chickens via exosome-mediated mechanisms without affecting abdominal fat deposition.MiR-27b-3p and miR-128-3p were found to inhibit adipogenic differentiation by targeting PPARG,thereby affecting IMF formation.In nutrition,nutrigenomics research has shown that fructose enhances IMF deposition by activating ChREBP,providing new targets for nutritional interventions.Adjusting dietary components,including energy,protein,amino acids,fatty acids,and phytochemicals(e.g.,rutin),has been shown to significantly improve meat quality in broilers.Maternal nutrition(e.g.,intake of energy,amino acids,vitamins,and trace elements)and IOF(e.g.,N-carbamylglutamate)have also been confirmed to significantly impact offspring meat quality,opening new avenues for improving embryonic nutrition.Based on these significant advancements,this review proposes strategies that integrate genetic and nutritional approaches.These strategies aim to modulate the differentiation fate of paraxial mesenchymal stem cells toward myogenic or adipogenic lineages and the interaction between muscle and adipose tissues.These insights would help to improve meat quality while ensuring the growth performance of broiler chickens.
基金supported by the National Natural Science Foundation of China (3207269732030102)+2 种基金CARS-PIG-35R&D Programmes of Guangdong Province (2018B020203003)Laboratory of Lingnan Modern Agriculture Project (NZ2021006)。
文摘Background Chinese indigenous pigs are popular with consumers for their juiciness,flavour and meat quality,but they have lower meat production.Insulin-like growth factor 2(IGF2) is a maternally imprinted growth factor that promotes skeletal muscle growth by regulating cell proliferation and differentiation.A single nucleotide polymorphism(SNP) within intron 3 of porcine IGF2 disrupts a binding site for the repressor,zinc finger BED-type containing 6(ZBED6),leading to up-regulation of IGF2 and causing major effects on muscle growth,heart size,and backfat thickness.This favorable mutation is common in Western commercial pig populations,but absent in most Chinese indigenous pig breeds.To improve meat production of Chinese indigenous pigs,we used cytosine base editor 3(CBE3)to introduce IGF2 intron3-C3071T mutation into porcine embryonic fibroblasts(PEFs) isolated from a male Liang Guang Small Spotted pig(LGSS),and single-cell clones harboring the desired mutation were selected for somatic cell nuclear transfer(SCNT) to generate the founder line of IGF2^(T/T) pigs.Results We found the heterozygous progeny IGF2^(C/T) pigs exhibited enhanced expression of IGF2,increased lean meat by 18%-36%,enlarged loin muscle area by 3%-17%,improved intramuscular fat(IMF) content by 18%-39%,marbling score by 0.75-1,meat color score by 0.53-1.25,and reduced backfat thickness by 5%-16%.The enhanced accumulation of intramuscular fat in IGF2^(C/T) pigs was identified to be regulated by the PI3K-AKT/AMPK pathway,which activated SREBP1 to promote adipogenesis.Conclusions We demonstrated the introduction of IGF2-intron3-C3071T in Chinese LGSS can improve both meat production and quality,and first identified the regulation of IMF deposition by IGF2 through SREBP1 via the PI3KAKT/AMPK signaling pathways.Our study provides a further understanding of the biological functions of IGF2and an example for improving porcine economic traits through precise base editing.
基金supported by the National Natural Science Foundation of China (32272847, U22A20516)the Key Research and Development Program of Shaanxi Province (2022ZDLNY01-04)the China Agriculture Research System of MOF and MARA (CARS-35)。
文摘Background Pork quality is affected by the type of muscle fibers, which is closely related to meat color, tenderness and juiciness. Exosomes are tiny vesicles with a diameter of approximately 30–150 nm that are secreted by cells and taken up by recipient cells to mediate communication. Exosome-mediated muscle-fat tissue crosstalk is a newly discovered mechanism that may have an important effect on intramuscular fat deposition and with that on meat quality. Various of adipose tissue-derived exosomes have been discovered and identified, but the identification and function of muscle exosomes, especially porcine fast/slow myotube exosomes, remain unclear. Here, we first isolated and identified exosomes secreted from porcine extensor digitorum longus(EDL) and soleus(SOL), which represent fast and slow muscle, respectively, and further explored their effects on lipid accumulation in longissimus dorsi adipocytes.Results Porcine SOL-derived exosomes(SOL-EXO) and EDL-derived exosomes(EDL-EXO) were first identified and their average particle sizes were approximately 84 nm with double-membrane disc-shapes as observed via transmission electron microscopy and scanning electron microscopy. Moreover, the intramuscular fat content of the SOL was greater than that of the EDL at 180 days of age, because SOL intramuscular adipocytes had a stronger lipid-accumulating capacity than those of the EDL. Raman spectral analysis revealed that SOL-EXO protein content was much greater than that of EDL-EXO. Proteomic sequencing identified 72 proteins that were significantly differentially expressed between SOL-EXO and EDL-EXO, 31 of which were downregulated and 41 of which were upregulated in SOL-EXO.Conclusions Our findings suggest that muscle-fat tissue interactions occur partly via SOL-EXO promoting adipogenic activity of intramuscular adipocytes.
文摘Introduction: Intramuscular depot betamethasone treatment had resulted in a significant improvement among fibromyalgia patients with elevated C-reactive protein (C-RP) levels. Here, we wanted to evaluate the same regimen of treatment among fibromyalgia patients with normal C-RP levels. These patients represent the overwhelming majority of fibromyalgia patients. Patients and Methods: Consecutive patients with fibromyalgia attending the outpatient rheumatology clinic, with normal C-RP level and negative serology, who had failed different medical treatment, were asked to participate in our study. All patients have qualified the American College of Rheumatology (ACR) criteria from 2010. After consent, patients had an intra-muscular injection of 14 mg depot betamethasone at the gluteal area. Just prior to the injection, 1 week and 1 month later, patients were interviewed by phone and asked to answer the Fibromyalgia Revised Questionnaire (FIQR). Wilcoxon’s signed ranked test was used to compare the results 1 week and 1 month following the injection, compared to the base line scores. Results: Seventeen (17) patients completed the study. Favorable effects were seen regarding 13 out of 19 parameters one week following the injection, including functional parameters, mood and anxiety, tenderness to touch and intolerance to noise and light. No significant favorable effect was seen 1 month following the injection except for one parameter: ability of walking for twenty minutes. Conclusions: IM depot betamethasone injection had very limited and transient favorable effects on fibromyalgia patients with normal C-RP levels. Such a treatment is not a recommended modality of routine treatment, among fibromyalgia patients with normal C-RP levels.
基金National Natural Sciences Foundation of China (No. 30671503)Youth Science and Technology Innovation Foundation (No. KJ05011)SRT Program (No. 0605A09) of Nanjing Agriculture University.
文摘Twenty-four male Kazak sheep and 30 Xinjiang fine wool sheep at different ages were selected to investigate the development-dependent expression levels of fatty acid synthase （FAS） gene and hormone-sensitive lipase （HSL） gene in muscle and their effects on the contents of intramuscular fat （IMF）. Longissimus dorsal muscle was sampled to measure IMF and total RNA was extracted to determine FAS and HSL mRNA expression levels by real-time PCR. The results showed that： l） The IMF content increased continuously with growth and showed significant differences （P 〈 0.05） between different age groups in male Kazak sheep, but in Xinjiang fine wool sheep there was no such difference observed. Furthermore, the IMF contents in Kazak were much higher （P 〈 0.01） than that of the other breed from day 30 to 90. 2） FAS mRNA expression level was the highest （P 〈 0.05） on day 0 in Kazak sheep and then declined with growth, in the other breed the gene showed a d‘ecline-rise-decline-rise＇ expression manner as the animals grew. HSL mRNA expression level had a similar model in two breeds, in Kazak sheep it was the highest on day 0 （P 〈 0.05） and in Xinjiang fine wool sheep on day 30 （P 〈 0.01）, then both decreased after this term. 3） In male Kazak sheep, FAS and HSL mRNA expression level were both negatively related to IMF content （r= -0.485 （P = 0.02）, r= -0.423 （P = 0.05））, and the ratio of FAS/HSL expression exhibited significantly negatively related IMF contents. In male Xinjiang sheep, there were no obvious relationship between FAS and HSL expression and IMF content （P 〉 0.05）.
基金This work was supported by the National Animal Breed Resource Preserve Project (No.200014) the Key Project of Shandong Science and Technology Development (No. 20059913) the Sciences Innovation Foundation of Shandong Agricultural University.
文摘Eighty-four castrated boars including Laiwu Black （LW） （weight 30-90 kg, n = 6） and Lulai Black （LL） （weight 40-100 kg, n = 6） were used to study the developmental changes of collagen type Ⅲ alpha 1 （Col3al） mRNA expression in the muscle and their association with intramuscular collagen （IMC）. The muscle total RNA was extracted to determine the abundance of Col3al mRNA using relative quantitative RT-PCR with β-actin mRNA as the internal standard. The results indicated that the developmental patterns of muscle Col3al mRNA in LW and LL pigs were similar. The abundance of Col3al mRNA increased with body weight, but decreased a little at 70 kg and 80 kg phases for LW and LL, respectively. On the whole, the expression level of Col3al mRNA in muscle of LW was higher than that of LL （P 〈 0.05）. Correlation analysis showed that the expression of Col3al mRNA in muscle was positively correlated with total and insoluble IMC, but was negatively correlated with IMC solubility for LW pigs （P 〈 0.01） and LL pigs （P 〈 0.05）, respectively. These results suggest that the muscle Col3al gene expression is affected by body weight and genotype and has important effect on IMC content and characteristics.
基金supported in part by Grant-in-Aid for JSPS Research Fellow
文摘Ectopic adiposity has gained considerable attention because of its tight association with metabolic and cardiovascular health in persons with spinal cord injury（SCI）. Ectopic adiposity is characterized by the storage of adipose tissue in non-subcutaneous sites. Magnetic resonance imaging（MRI） has proven to be an effective tool in quantifying ectopic adiposity and provides the opportunity to measure different adipose depots including intermuscular adipose tissue（IMAT） and intramuscular adipose tissue（Intra MAT） or intramuscular fat（IMF）. It is highly important to distinguish and clearly define these compartments, because controversy still exists on how to accurately quantify these adipose depots. Investigators have relied on separating muscle from fat pixels based on their characteristic signal intensities. A common technique is plotting a threshold histogram that clearly separates between muscle and fat peaks. The cut-offs to separate between muscle and fat peaks are still not clearly defined and different cut-offs have been identified. This review will outline and compare the Midpoint and Otsu techniques, two methods used to determine the threshold between muscle and fat pixels on T1 weighted MRI. The process of water/fat segmentation using the Dixon method will also be outlined. We are hopeful that this review will trigger more research towards accurately quantifying ectopic adiposity due to its high relevance to cardiometabolic health after SCI.
基金This work was supported by a Cooperation Research Project(2020R1A2B5B02001843)funded by the National Research Foundation of Korea.
文摘During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).Based on the results of previous studies,other adipose tissue depots(e.g.,perirenal and subcutaneous)develop from the fetal stage primarily as brown adipose tissue.The hyperplastic stage of intramuscular adipose is considered to develop from late pregnancy,but there is no evidence indicating that intramuscular adipose tissue develops initially as brown adipose tissue.Hyperplastic growth of intramuscular adipose continues well into postweaning and is dependent on the timing of the transition to grain-based diets;thereafter,the late-stage development of intramuscular adipose tissue is dominated by hypertrophy.For muscle development,hyperplasia of myoblasts lasts from early(following development of somites in the embryo)to middle pregnancy,after which growth of muscle is the result of hypertrophy of myofibers.Vitamin A is a fat-soluble compound that is required for the normal immunologic function,vision,cellular proliferation,and differentiation.Here we review the roles of vitamin A in intramuscular adipose tissue and muscle development in cattle.Vitamin A regulates both hyperplasia and hypertrophy in in vitro experiments.Vitamin A supplementation at the early stage and restriction at fattening stage generate opposite effects in the beef cattle.Appropriate vitamin A supplementation and restriction strategy increase intramuscular adipose tissue development(i.e.,marbling or intramuscular fat)in some in vivo trials.Besides,hyperplasia and hypertrophy of myoblasts/myotubes were affected by vitamin A treatment in in vitro trials.Additionally,some studies reported an interaction between the alcohol dehydrogenase-1C(ADH1C)genotype and vitamin A feed restriction for the development of marbling and/or intramuscular adipose tissue,which was dependent on the timing and level of vitamin A restriction.Therefore,the feed strategy of vitamin A has the visible impact on the marbling and muscle development in the cattle,which will be helpful to promote the quality of the beef.
基金funding from the Spanish Ministry of Economy and Competitiveness and the European Union Regional Development Funds(AGL2015–65846-R grant)partially supported by the Centre for the Development of Industrial Technology(IDI-20150115 project)SG is recipient of a PhD scholarship from the Spanish Ministry of Science and Innovation(BES-2014-FPU13/04975)
文摘Background: Intramuscular fat(IMF) content is a relevant trait for high-quality meat products such as dry-cured ham,but increasing IMF has the undesirable correlated effect of decreasing lean growth.Thus,there is a need to find selection criteria for IMF independent from lean growth.In pigs,the proportion of linoleic(C18:2) and arachidonic(C20:4) acids decline with fat deposition and therefore they can be considered as indicators of fatness.The aim of this research was to estimate the genetic variation for C18:2 and C20:4 in IMF and their genetic correlations with IMF and lean growth traits,with the objective to assess their potential as specific biomarkers of IMF.The analysis was conducted using a full-pedigreed Duroc resource line with 91,448 records of body weight and backfat thickness(BT) at 180 days of age and 1371 records of fatty acid composition in the muscle gluteus medius.Results: The heritability estimates for C18:2 and C20:4 in IMF,whether expressed in absolute(mg/g of muscle) or in relative(mg/g of fatty acid) terms,as well as for their ratio(C20:4/C18:2),were high(> 0.40),revealing that the C18:2 to C20:4 pathway is subjected to substantial genetic influence.Litter effects were not negligible,with values ranging from8% to 15% of the phenotypic variance.The genetic correlations of C18:2 and C20:4 with IMF and BT were negative(-0.75 to-0.66,for IMF,and-0.64 to-0.36,for BT),if expressed in relative values,but almost null(-0.04 to 0.07),if expressed in absolute values,except for C18:2 with IMF,which was highly positive(0.88).The ratio of C20:4 to C18:2 also displayed a stronger genetic correlation with IMF(-0.59) than with BT(-0.10).Conclusions: The amount of C18:2 in muscle can be used as an IMF-specific biomarker.Selection for the absolute amount of C18:2 is expected to deliver a similar response outcome as selection for IMF at restrained BT.Further genetic analysis of the C18:2 metabolic pathway may provide new insights into differential fat deposition among adipose tissues and on candidate genes for molecular markers targeting specifically for one of them.
基金financed by the Department of Science and Technology of Yunnan Province(2009AD010)
文摘Fatty acid composition of neutral lipids （NLs）, phospholipids （PLs） and free fatty acids （FFAs） from intramuscular fat （IMF）, lipid oxidation and lipase activity in muscle Semimembranosus （SM） and msucle Biceps femoris （BF） of dry-cured Xuanwei ham during the 90-d salting stages were analysed. The salt content increased from 0.34 to 3.52%in BF and from 0.10 to 5.42%in SM during the 90 d salting stage, respectively. PLs of IMF in both BF and SM decreased 54.70%（P〈0.001） and 34.64%（P〈0.05）, furthermore, the saturated fatty acids （SFA）, monounsaturated fatty acids （MUFA） and polyunsaturated fatty acids （PUFA） of PLs in both muscles were hydrolysed almost isochronously. FFAs were increased from 0.46 g 100 g-1 lipids to 2.92 g 100 g-1 lipids in BF at the end of salting, which was lower than SM （from 1.29 g 100 g-1 lipids to 9.70 g 100 g-1 lipids）. The activities of acid lipase, neutral lipase and acid phospholipase all remained active in the 90 d. The thiobarbituric acid reactive substances （TBARS） was slowly increased to 1.34 mg kg-1 muscle in BF and to 2.44 mg kg-1 muscle in SM during the salting stage. In conclusion, the controlled salting process prompted the hydrolysis of PLs of IMF notably and increased the lipid oxidation of muscles within some limits.
基金supported by grants from the National Natural Science Foundation (31872979, 31572366)the National Key Research and Development Program of China (2017YFD0502002)the National Basic Research Programs of China (2015CB943102)。
文摘Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a novel miRNA implicated in porcine IMF adipogenesis was found, and its effect and regulatory mechanism were further explored with respect to intramuscular preadipocyte proliferation and differentiation.Results: By porcine adipose tissue miRNA sequencing analysis, we found that miR-146a-5p is a potential regulator of porcine IMF adipogenesis. Further studies showed that miR-146a-5p mimics inhibited porcine intramuscular preadipocyte proliferation and differentiation, while the miR-146a-5p inhibitor promoted cell proliferation and adipogenic differentiation. Mechanistically, miR-146a-5p suppressed cell proliferation by directly targeting SMAD family member 4(SMAD4) to attenuate TGF-β signaling. Moreover, miR-146a-5p inhibited the differentiation of intramuscular preadipocytes by targeting TNF receptor-associated factor 6(TRAF6) to weaken the AKT/mTORC1 signaling downstream of the TRAF6 pathway.Conclusions: MiR-146a-5p targets SMAD4 and TRAF6 to inhibit porcine intramuscular adipogenesis by attenuating TGF-β and AKT/mTORC1 signaling, respectively. These findings provide a novel miRNA biomarker for regulating intramuscular adipogenesis to promote pork quality.
文摘Pain following depot intramuscular （IM） injection of oil vehicle-based drugs has been little studied. This study aimed to determine prospectively the prevalence,determinants,severity and functional consequences of pain during the week after IM injection of 1 000 mg testosterone undecanoate （TU） in a 4-mL castor oil vehicle. Androgendeficient men receiving regular T replacement therapy at an academic andrology clinic were recruited to report pain scores using a coloured visual linear analogue scale at seven times over the first day and daily for a week after a deep IM gluteal injection. The time course and covariables influencing pain scores were analysed by mixed model analysis of variance （ANOVA）. Following 168 injections in 125 men,pain was reported by 80% of men,peaking immediately after injection,reaching only moderate severity,lasting 1-2 days and returning to baseline by day 4.The pain required little analgesic use and produced minimal interference in daily activities. The time course of pain scores was reproducible in the 43 men who underwent two consecutive injections. Pain was more severe in men who had an earlier painful injection,but less severe in older and more obese men. There were negligible differences in post-injection pain experience between experienced nurses administering injections. Deep IM gluteal injection of depot TU in 4-mL castor oil is well tolerated and post-injection pain is influenced by earlier painful injection experience,as well as age and obesity.
基金funded by the National Natural Science Foundation of China (31972994)Key Research and Development Program of Ningxia Province (2019BEF02004)+1 种基金National Beef and Yak Industrial Technology System (CARS-37)National Key Research and Development Program of China (2018YFD0501700)。
文摘Background Long non-coding RNAs(lncRNAs)regulate numerous biological processes,including adipogenesis.Research on adipogenesis will assist in the treatment of human metabolic diseases and improve meat quality in livestock,such as the content of intramuscular fat(IMF).However,the significance of lncRNAs in intramuscular adipogenesis remains unclear.This research aimed to reveal the lncRNAs transcriptomic profiles in the process of bovine intramuscular adipogenesis and to identify the lncRNAs involved in the adipogenesis of bovine intramuscular adipocytes.Results In this research,a landscape of lncRNAs was identified with RNA-seq in bovine intramuscular adipocytes at four adipogenesis stages(0 d,3 d,6 d,and 9 d after differentiation).A total of 7035 lncRNAs were detected,including 3396 novel lncRNAs.Based on the results of differential analysis,co-expression analysis,and functional prediction,we focused on the bovine intramuscular adipogenesis-associated long non-coding RNA(BIANCR),a novel lncRNA that may have an important regulatory function.The knockdown of BIANCR inhibited proliferation and promoted apoptosis of intramuscular preadipocytes.Moreover,BIANCR knockdown inhibited intramuscular adipogenesis by regulating the ERK1/2 signaling pathway.Conclusion This study obtained the landscape of lncRNAs during adipogenesis in bovine intramuscular adipocytes.BIANCR plays a crucial role in adipogenesis through the ERK1/2 signaling pathway.The results are noteworthy for improving beef meat quality,molecular breeding,and metabolic disease research.
基金funded by grants from the National Natural Science Foundation of China(31872340)the Basic Research from Institute of Animal Sciences of Chinese Academy of Agricultural Sciences(2019-YWF-YB-07)+3 种基金the Agricultural Science and Technology Innovation Program(CAASZDRW202005)the Basic Research from Chinese Academy of Agricultural Sciences(Y2019XK06)the Agricultural Science and Technology Innovation Program(ASTIP-IAS04)the China Agriculture Research System of MOF and MARA(CARS-41).
文摘Background:Increasing intramuscular fat(IMF)is an important strategy to improve meat quality,but the regulation mechanism of IMF deposition needs to be systematically clarified.Results:A total of 520 chickens from a selected line with improved IMF content and a control line were used to investigate the biochemical mechanism of IMF deposition in chickens.The results showed that the increased IMF would improve the flavor and tenderness quality of chicken meat.IMF content was mainly determined both by measuring triglyceride(TG)and phospholipid(PLIP)in muscle tissue,but only TG content was found to be decisive for IMF deposition.Furthermore,the increase in major fatty acid(FA)components in IMF is mainly derived from TGs(including C16:0,C16:1,C18:1n9c,and C18:2n6c,etc.),and the inhibition of certain very-long-chain FAs would help to IMF/TG deposition.Conclusions:Our study elucidated the underlying biochemical mechanism of IMF deposition in chicken:Prevalent accumulation of long-chain FAs and inhibitions of medium-chain FAs and very long chain FA would jointly result in the increase of TGs with the FA biosynthesis and cellular uptake ways.Our findings will guide the production of high-quality chicken meat.
基金Supported by Natural Science Foundation of Guangxi Bureau of Aquatic Products and Animal Husbandry(GYMK201452035 and GYMK1304510)~~
文摘Intramuscular fat （IMF）, an important flavor precursor of porcine meat, is closely related to pork quality traits such as pH, color, tenderness, water-holding capacity （WHC） and juiciness, and thus is one of the important factors affecting pork quality. Pork IMF content is not only associated with swine breed on heredity, but also influenced by the alteration of nutrients in diet. These may give a possibility for researchers to improve the IMF content and pork quality by their work on swine breed or heredity, and nutrition regulation in diet. Therefore, this article summarizes the effects of swine breed and nutrition regulation on IMF content briefly to provide some information for future researches.
基金supported by the National Natural Science Foundation of China(No.31372305)the Agricultural Science and Technology Innovation Program(No.ASTIP-IAS04)the Project of State Key Laboratory of Animal Nutrition(No.2004DA125184G1101),China
文摘Intramuscular fat （IMF） is a crucial factor in the quality of chicken meat. The genetic basis underlying it is complex. Follicle-stimulating hormone （FSH）, well-known as an effector in reproductive tissues, was recently discovered to stimulate abdominal fat accumulation in chicken. The effect of FSH on IMF accumulation and the underlying molecular regulatory mechanisms controlling both IMF and abdominal fat deposition in vivo are largely unknown. In this study, two groups of chickens were treated with chicken FSH or a placebo. The lipid content of breast muscle, abdominal fat volume, and serum concentrations of FSH were examined. Related genes implicated in breast muscle and abdominal fat accumulation were also investigated. Compared to the control group, the triglyceride （TG） content of breast muscle and the percentage of abdominal fat in FSH-treated chickens were significantly increased by 64.9% and 56.5% （P〈0.01）, respectively. The FSH content in the serum of FSH-treated chickens was 2.1 times than that of control chickens （P〈0.01）. Results from quantitative real-time polymerase chain reaction （qRT-PCR） assays showed that relative expression levels of fatty acid synthase （FAS）, lipoprotein lipase （LPL）, diacylglycerol acyltransferase 2 （DGAT2）, adipocyte fatty acid binding protein （A-FABP）, and peroxisome proliferator-activated receptor ~ （PPARy） were significantly upregulated in breast muscle following FSH treatment （P〈0.01）. Treatment with FSH also signifi- cantly increased relative expression levels of FAS, LPL, DGA T2, A-FABP, and PPARy in abdominal fat tissue （P〈0.05） The results of principal component analysis （PCA） for gene expression （breast muscle and abdominal fat） showed that the control and FSH treatment groups were well separated, which indicated the reliability of the data. This study demonstrates that FSH plays an important role in IMF accumulation in female chickens, which likely involves the regulation of biosynthesis genes related to lipid metabolism.
文摘We report the case of a cervical pregnancy successfully treated with intramuscular injection of methotrexate(MTX) and intramniotic administration of potassium chloride. A 41-year-old woman was admitted to our Department with the suspicion of ectopic pregnancy. Transvaginal ultrasound revealed empty endometrialcavity, gestational sac within the cervical canal and embryonic echo measuring crown rump length 1.5 mm. Serum beta human chorionic gonadotropine(β-HCG) was measured 28590 IU/L. No cardiac activity was detected. The diagnosis of a cervical pregnancy was made. Patient was treated with intramuscular administration of methotrexate(50 mg/m2) in combination with ultrasoundguided intramniotic injection of KCl(2 meq/mL). Gradual decrease of β-HCG levels as well as ultrasound observation of collapsed gestational sac was observed. No curettage was necessitated. Patient was discharged on day 10 th and was set in follow-up on a weekly basis. β-HCG values were measured < 10 IU/L on 56 th day after MTX administration. Intramuscular administration of MTX may be effective in treatment of cervical pregnancy without additional interventional measures.
文摘To study the kinetics in vivo of a Hantaan virus DNA vaccine, we constructed a fusion DNA vaccine, pEGFP/S, by cloning the S segment of Hantavirus into the vector, pEGFP-C1, which encodes Green fluorescent protein EGFP. In this report, we provide evidence that pEGFP/S was distributed and persistently expressed for more than 60 days in several organs after inoculation. Our findings suggest that the persistent immune responses induced by a Hantaan virus DNA vaccine are likely due to the plasmid pEGFP/S deposited in vivo, which acts as a booster immunization.
文摘AIM： To compare intradermal （ID） and intramuscular （IM） booster doses, which have been used in healthy and high risk subjects, such as healthcare workers, haemodialysis patients, human immunodeficiency virus patients, and renal transplant recipients unresponsive to initial hepatitis B vaccination, in celiac individuals. METHODS： We conducted our study on 58 celiac pa- tients, vaccinated in the first year of life, whose blood analysis had showed the absence of protective hepati- tis B virus （HBV） antibodies. All patients had received the last vaccine injection at least one year before study enrolment and they had been on a gluten free diet for at least 1 year. In all patients we randomly performed an HBV vaccine booster dose by ID or IM route. Thirty celiac patients were revaccinated with recombinant hepatitis B vaccine （Engerix B） 2 μg by the ID route, while 28 celiac patients were revaccinated with Engerix B 10 μg by the IM route. Four weeks after every boost- er dose, the anti-hepatitis B surface （HBs） antibody titer was measured by an enzyme-linked immune- adsorbent assay. We performed a maximum of three booster doses in patients with no anti-HBs antibodies after the first or the second vaccine dose. The cut off value for a negative anti-HBs antibody titer was 10 IU/L.Patients with values between 10 and 100 IU/L were considered ＂low responders＂ while patients with an antibody titer higher than 1000 IU/L were considered ＂high responders＂. RESULTS： No significant difference in age, gender, du- ration of illness, and years of gluten intake was found between the two groups. We found a high percent- age of ＂responders＂ after the first booster dose （ID = 76.7%, IM = 78.6%） and a greater increase after the third dose （ID = 90%, IM = 96.4%） of vaccine in both groups. Mloreover we found a significantly higher num- ber of high responders （with an anti-HBs antibody titer 〉 1000 IU/L） in the ID （40%） than in the IM （7.1%） group, and this difference was evident after the first booster dose of vaccination （P 〈 0.01）. No side effects were recorded in performing delivery of the vaccine by either the ID or IM route. CONCLUSION： Our study suggests that both ID and IM routes are effective and safe options to administer a booster dose of HBV vaccine in celiac patients. Howev- er the ID route seems to achieve a greater number of high responders and to have a better cost/benefit ratio.
