Chinese hamster with Chinese characteristics is used in experiments,and it is of great value in the field of medical biology research.However,at present,there is no high-efficiency method for evaluating the genetic qu...Chinese hamster with Chinese characteristics is used in experiments,and it is of great value in the field of medical biology research.However,at present,there is no high-efficiency method for evaluating the genetic quality of Chinese hamsters.Here,we developed a novel Chinese hamster genetic quality detection system using single-nucleotide polymorphism(SNP)markers.To find SNP loci,we conducted whole genome sequencing on 24 Chinese hamsters.Then,we employed an SNP locus screening criterion that we set up previously and initially screened 214 SNP loci with wide genome distribution and high polymorphism level.Subsequently,we developed the SNP detection system using a multitarget region capture technique based on second-generation sequencing,and a 55 SNP panel for genetic evaluation of Chinese hamster populations was developed.PopGen.32.analysis results showed that the average effective allele number,Shannon index,observed heterozygosity,expected heterozygosity,average heterozygosity,polymorphism information,and other genetic parameters of Chinese hamster population A were higher than those in population B.Using scientific screening and optimization,we successfully developed a novel Chinese hamster SNP genetic detection system that can efficiently and accurately analyze the genetic quality of the Chinese hamster population.展开更多
Being widespread across the globe,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)keeps evolving and generating new variants and continuously poses threat to public health,especially to the population with ...Being widespread across the globe,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)keeps evolving and generating new variants and continuously poses threat to public health,especially to the population with chronic comorbidities.Diabetes mellitus is one of high-risk factors for severe outcome of coronavirus disease 2019(COVID-19).Establishment of animal models that parallel the clinical and pathological features of COVID-19 complicated with diabetes is thus highly essential.Here,in this study,we constructed leptin receptor gene knockout hamsters with the phenotype of diabetes mellitus(db/db),and revealed that the diabetic hamsters were more susceptible to SARS-CoV-2 and its variants than wild-type hamsters.SARS-CoV-2 and its variants induced a stronger immune cytokine response in the lungs of diabetic hamsters than in wild-type hamsters.Comparative histopathology analyses also showed that infection of SARS-CoV-2 and the variants caused more severe lung tissue injury in diabetic hamsters,and may induce serious complications such as diabetic kidney disease and cardiac lesions.Our findings demonstrated that despite the decreased respiratory pathogenicity,the SARS-CoV-2 variants were still capable of impairing other organs such as kidney and heart in diabetic hamsters,suggesting that the risk of evolving SARS-CoV-2 variants to diabetic patients should never be neglected.This hamster model may help better understand the pathogenesis mechanism of severe COVID-19 in patients with diabetes.It will also aid in development and testing of effective therapeutics and prophylactic treatments against SARS-CoV-2 variants among these high-risk populations.展开更多
Background:Thromboelastography(TEG)is a widely utilized clinical testing method for real-time monitoring of platelet function and the thrombosis process.Lipid metab-olism disorders are crucial risk factors for thrombo...Background:Thromboelastography(TEG)is a widely utilized clinical testing method for real-time monitoring of platelet function and the thrombosis process.Lipid metab-olism disorders are crucial risk factors for thrombosis.The lipid metabolism charac-teristics of hamsters resemble those of humans more closely than mice and rats,and their relatively large blood volume makes them suitable for studying the mechanisms of thrombosis related to plasma lipid mechanisms.Whole blood samples from golden Syrian hamsters and healthy humans were obtained following standard clinical pro-cedures.TEG was employed to evaluate coagulation factor function,fibrinogen(Fib)function,platelet function,and the fibrinolytic system.Methods:The whole blood from hamster or healthy human was isolated following the clinical procedure,and TEG was employed to evaluate the coagulation factor func-tion,Fib function,platelet function,and fibrinolytic system.Coagulation analysis used ACLTOP750 automatic coagulation analysis pipeline.Blood routine testing used XN-2000 automatic blood analyzer.Results:TEG parameters revealed that hamsters exhibited stronger coagulation fac-tor function than humans(reaction time[R],p=0.0117),with stronger Fib function(alpha angle,p<0.0001;K-time[K],p<0.0001).Platelet function did not differ signifi-cantly(maximum amplitude[MA],p=0.077).Hamsters displayed higher coagulation status than humans(coagulation index[CI],p=0.0023),and the rate of blood clot dissolution in hamsters differed from that in humans(percentage lysis 30 min after MA,p=0.02).Coagulation analysis parameters indicated that prothrombin time(PT)and activated partial thromboplastin time(APTT)were faster in hamsters than in hu-mans(PT,p=0.0014;APTT,p=0.03),whereas the Fib content was significantly lower in hamsters than in humans(p<0.0001).No significant difference was observed in thrombin time(p=0.1949).Conclusions:In summary,TEG could be used to evaluate thrombosis and bleeding parameters in whole blood samples from hamsters.The platelet function of hamsters closely resembled that of humans,whereas their coagulation function was signifi-cantly stronger.展开更多
Coxsackievirus B3(CVB3)is the pathogen causing hand,foot and mouth disease(HFMD),which manifests across a spectrum of clinical severity from mild to severe.However,CVB3-infected mouse models mainly demonstrate viral m...Coxsackievirus B3(CVB3)is the pathogen causing hand,foot and mouth disease(HFMD),which manifests across a spectrum of clinical severity from mild to severe.However,CVB3-infected mouse models mainly demonstrate viral myocarditis and pancreatitis,failing to replicate human HFMD symptoms.Although several enteroviruses have been evaluated in Syrian hamsters and rhesus monkeys,there is no comprehensive data on CVB3.In this study,we have first tested the susceptibility of Syrian hamsters to CVB3 infection via different routes.The results showed that Syrian hamsters were successfully infected with CVB3 by intraperitoneal injection or nasal drip,leading to nasopharyngeal colonization,acute severe pathological injury,and typical HFMD symptoms.Notably,the nasal drip group exhibited a longer viral excretion cycle and more severe pathological damage.In the subsequent study,rhesus monkeys infected with CVB3 through nasal drips also presented signs of HFMD symptoms,viral excretion,serum antibody conversion,viral nucleic acids and antigens,and the specific organ damages,particularly in the heart.Surprisingly,there were no significant differences in myocardial enzyme levels,and the clinical symptoms resembled those often associated with common,mild infections.In summary,the study successfully developed severe Syrian hamsters and mild rhesus monkey models for CVB3-induced HFMD.These models could serve as a basis for understanding the disease pathogenesis,conducting pre-trial prevention and evaluation,and implementing post-exposure intervention.展开更多
In order to understand the effect of gradual changes in photoperiod on immune function, adult female Siberian hamsters (Phodopus sungorus) were randomly divided into the control group (12L:12D, Con, n = 11) and the sh...In order to understand the effect of gradual changes in photoperiod on immune function, adult female Siberian hamsters (Phodopus sungorus) were randomly divided into the control group (12L:12D, Con, n = 11) and the shortening day length group (SD, n = 11), in which day length was reduced from 12:12 h to 8:16 h light-dark cycle at the pace of half an hour every week. Meanwhile the winter immunoenhancement hypothesis, which holds that animals’ immune function would be enhanced in winter or winter-like conditions, was tested. Gradual shortening day length had no effect on body mass and body composition including wet carcass mass, the subcutaneous, retroperitoneal, mesenteric and total body fat masses in Siberian hamsters. The masses of liver and small intestine with contents were higher in the SD group than in the Con group, however other organ masses such as brain, heart, kidney and so on did not differ between the two groups. Phytohemagglutinin (PHA) response after 24 h of PHA injection was enhanced by the shortening photoperiod, which supported the winter immunoenhancement hypothesis. The masses of spleen and thymus, white blood cells, bacteria killing capacity indicative of innate immunity were not affected, which did not support this hypothesis. In summary, gradually decrease in day length increased cellular immunity, but had no effect on other immunological parameters in Siberian hamsters.展开更多
Hypertriglyceridemia(HTG)often accompanies diabetes and is considered a risk factor for diabetic vascular complications.However,inducing diabetic HTG typically requires high-fat diets in certain animal models.Leveragi...Hypertriglyceridemia(HTG)often accompanies diabetes and is considered a risk factor for diabetic vascular complications.However,inducing diabetic HTG typically requires high-fat diets in certain animal models.Leveraging our newly developed LDL receptor knockout hamster model,which exhibits features akin to human lipid metabolism,we sought to determine whether these animals would develop HTG without dietary manipulations in diabetes.Diabetes was induced via intraperitoneal injection of STZ in wild type and heterozygous LDL receptor deficient hamsters.Blood glucose,triglyceride,and cholesterol were measured over 60 days.Plasma TG clearance was determined via olive oil gavage.The effect of insulin on diabetic HTG was assessed on Day 60 post-diabetes induction.Blood glucose increased over threefold,while plasma insulin decreased to 30%of controls after STZ injection in both wild type and heterozygous hamsters by Day 7,remaining stable for 60 days.Plasma TG in wild-type hamsters remained unchanged at Day 7 post-STZ injection but increased slightly thereafter.Conversely,heterozygous hamsters exhibited severe HTG by Day 7 until the end of the study.Olive oil gavage revealed much slower plasma triglyceride clearance in heterozygous hamsters compared to WT animals,despite significantly reduced lipoprotein lipase activity in post-heparin plasma in both animals.Hyperglycemia and HTG in heterozygous hamsters were reversed to pre-diabetic levels following intraperitoneal insulin administration.In conclusion,severe HTG in diabetic heterozygous LDL receptor deficient hamsters developed spontaneously and was insulin-dependent.Thus,this hamster model holds promise for effectively studying the complications associated with human diabetic HTG.展开更多
Aim： To detect the expression of hepatitis B virus （HBV） genes （HB S and C genes） in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fer...Aim： To detect the expression of hepatitis B virus （HBV） genes （HB S and C genes） in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization （IVF） technique. Methods： Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method. Polymerase chain reaction （PCR） was used to detect HB S and pre-Core/Core （pre-C/C） coding genes both in one- and two-cell embryos. Reverse transcription-PCR （RT-PCR） analysis was used to study the expression of the two genes. Fluorescence in situ hybridization （FISH） analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome. Results： Both HB S and pre-C/C coding genes are present and transcribed in one- and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences. Conclusion： Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells. These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line.展开更多
Objective To examine the effects of chlorogenic acid （CGA） on lipid and glucose metabolism under a high dietary fat burden and to explore the possible role of peroxisome proliferator-activated receptor-α （PPAR-α...Objective To examine the effects of chlorogenic acid （CGA） on lipid and glucose metabolism under a high dietary fat burden and to explore the possible role of peroxisome proliferator-activated receptor-α （PPAR-α） in these effects. Methods Twenty male golden hamsters were randomly divided into CGA treatment group （n=10, given peritoneal injection of CGA solution prepared with PBS, 80 mg CGA/kg body weight daily）, and control group （n=10, given PBS i.p. at the average volume of the treatment group）. Animals in both groups were given 15% high fat diet. Eight weeks after treatment with CGA, the level of biochemical parameters in fasting serum and tissues and the expression of hepatic mRNA and protein PPAR-α were determined. Results Eight weeks after treatment with CGA, the levels of fasting serum triglyceride （TG）, free fatty acid （FFA）, total cholesterol （TC）, low density lipoprotein cholesterol （LDL-C）, high density lipoprotein cholesterol （HDL-C）, glucose （FSG）, and insulin （FSI） were significantly lower in the GGA treatment group than in the control group. CGA also led to higher activity of hepatic lipase （HL） lower contents of TG and FFA in liver, and lower activity of lipoprotein lipase （LPL） in skeletal muscle. Furthermore, CGA significantly elevated significantly elevated the expression level of mRNA and protein expression in hepatic PPAR-α. Conclusion CGA can modify lipids and glucose metabolism, which may be attributed to PPAR-α facilitated lipid clearance in liver and improved insulin sensitivity.展开更多
Aim To investigate the role of the Chinese herbal medicine Xianhuayin on the reversal of 7,12-dimethylbenz[a]anthracene （DMBA）-induced premalignant mucosal lesions in the oral buccal pouch of golden hamsters. Method...Aim To investigate the role of the Chinese herbal medicine Xianhuayin on the reversal of 7,12-dimethylbenz[a]anthracene （DMBA）-induced premalignant mucosal lesions in the oral buccal pouch of golden hamsters. Methodology The animals were randomly divided into a non-diseased control group （n=5） and an experimental group including 50 animals in which the buccal mucosa had been painted with DMBA （0.5% in acetone） to generate an oral mucosa premalignant lesion. Animals in the experi- mental group were further divided into Xianhuayin-treated group （n=30）, untreated prem＇alignant lesion group （n=10） and normal saline （NS）-treated group （n=10）. The cheek （buccal） pouch mucosa of the golden hamsters in each group was observed with light and electron microscopy eight weeks after intragastric administration with NS or Xianhuayin. Results In the non-diseased control group, the buccal mucosa was keratinized and stratified squamous epithelium under a light microscope. In the untreated premalignant lesion group, variable degrees of epithelial dysplasia was observed. The irregular epithelial mucosa gradually became distinct in the Xianhuayin-treated group. Scanning electronic microscopic （SEM） analysis showed that surface of the cells exhibited honeycomb structures in the hamster of untreated- group. The cells were morphologically irregular, overlapped and loosened in the untreated premalignant lesion group. Most of the cell surface exhibited honeycomb structure in the Xianhuayin-treated group. Transmission electronic micro- scopic （TEM） analysis showed that buccal mucosal epithelial cells were morphologically regular in the non-diseased control group. Desmosomes and tonofibrils were reduced and the nucleus was morphologically irregular in the untreated premalignant lesion group. In the Xianhuayin-treated group, the widening intercellular gap was gradually reduced, desmosomes and the cells becoming morphologically regular. No significant difference was observed between the hamsters in NS-treated group and those in the untreated premalignant lesion group. Significant therapeutic efficacy was observed in the group receiving Xianhuayin. Conclusion Xianhuayin is effective in the reversal of DMBA-induced premalignant lesions in the buccal pouch of golden hamsters.展开更多
AIM： TO investigate the effects of ursodeoxycholic acid （UDCA） on chenodeoxycholic acid （CDCA）-induced liver injury in hamsters, and to elucidate a correlation between liver injury and bile acid profiles in the l...AIM： TO investigate the effects of ursodeoxycholic acid （UDCA） on chenodeoxycholic acid （CDCA）-induced liver injury in hamsters, and to elucidate a correlation between liver injury and bile acid profiles in the liver.METHODS： Liver injury was induced in hamsters by administration of 0.5% （w/w） CDCA in their feed for 7 d. UDCA （50 mg/kg and 150 mg/kg） was administered for the last 3 d of the experiment.RESULTS： At the end of the experiment, serum alanine aminotransferase （ALl） increased more than 10 times and the presence of liver injury was confirmed histologically. Marked increase in bile acids was observed in the liver. The amount of total bile acids increased approximately three-fold and was accompanied by the increase in hydrophobic bile acids, CDCA and lithocholic acid （LCA）. UDCA （50 mg/kg and 150 mg/kg） improved liver histology, with a significant decrease （679.3 ±77.5 U/L vs 333.6 ± 50.4 U/L and 254.3 ±35.5 U/ L, respectively, P 〈 0.01） in serum ALT level. UDCA decreased the concentrations of the hydrophobic bile acids, and as a result, a decrease in the total bile acid level in the liver was achieved.CONCLUSION： The results show that UDCA improves oral CDCA-induced liver damage in hamsters. The protective effects of UDCA appear to result from a decrease in the concentration of hydrophobic bile acids, CDCA and LCA, which accumulate and show the cytotoxicity in the liver.展开更多
BACKGROUND:Our earlier study with cultured gallbladder epithelial cells demonstrated that statins(HMG-CoA reductase inhibitors)activate the expression of PPARαand PPARγ, consequently blocking the production of pro-i...BACKGROUND:Our earlier study with cultured gallbladder epithelial cells demonstrated that statins(HMG-CoA reductase inhibitors)activate the expression of PPARαand PPARγ, consequently blocking the production of pro-inflmmatory cytokines.The present study used hamsters to investigate the effects of pavastatin on PPARα/PPARγexpression in the liver and gallbladder epithelium,and to determine whether pravastatin suppresses cholesterol crystal formation in the gallbladder. METHODS:A total of 40 Golden Syrian male hamsters(4 weeks old)were randomly assigned to four groups(basal diet control; basal diet+pavastatin;high cholesterol diet;high cholesterol diet+pravastatin).All hamsters were 11 weeks old at the end of the experiment.The liver,gallbladder and bile were harvested. Immunohistochemical staining and Western blotting for PPARαand PPARγwere performed in the liver and gallbladder. A drop of fresh bile was examined for cholesterol crystals under a microscope. RESULTS:In the gallbladder and liver of the hamsters, pravastatin activated the PPARαand PPARγexpression of gallbladder epithelial cells and hepatocytes,and particularly the response of PPARγwas much stronger than that of PPARα. Pravastatin suppressed the formation of cholesterol gallstones or crystals in the gallbladder. CONCLUSION:Pravastatin is an effective medication to activate PPARs(especially PPARγ)in the liver and the gallbladder epithelium of hamsters,and contributes to the prevention of gallstone formation.展开更多
The immotile testicular mammalian spermatozoon gets transformed into a motile spermatozoon during ＇epididymal maturation＇. During this process, the spermatozoa transit from the caput to the cauda epididymis and unde...The immotile testicular mammalian spermatozoon gets transformed into a motile spermatozoon during ＇epididymal maturation＇. During this process, the spermatozoa transit from the caput to the cauda epididymis and undergo a number of distinct morphological, biophysical and biochemical changes, including changes in protein composition and protein modifications, which may be relevant to the acquisition of motility potential. The present proteome-based study of the hamster epididymal spermatozoa of caput and cauda led to the identification of 113 proteins spots using Matrix- assisted laser desorption/ionization tandem mass spectrometry （MALDI-MS/MS） analysis. Comparison of these 113 protein spots indicated that 30 protein spots （corresponding to 20 proteins） were significantly changed in intensity. Five proteins were increased and eleven were decreased in intensity in the cauda epididymal spermatozoa. In addition, two proteins, glucose-regulated protein precursor （GRP78） and tumor rejection antigen （GP96）, were unique to the caput epididymal spermatozoa, while one protein, fibrinogen-like protein 1, was unique to cauda epididymal spermatozoa. A few of the five proteins, which increased in intensity, were related to sperm metabolism and ATP production during epididymal maturation. The changes in intensity of a few proteins such as ERp57, GRP78, GP96, Hsp60, Hsp70, and dihydrolipoamide S-acetyltransferase were validated by immunoblotting. The present study provides a global picture of the changes in protein composition occurring during hamster sperm epididymal maturation, besides being the first ever report on the proteome of hamster spermatozoa.展开更多
Food restriction （FR） and refeeding （Re） have been suggested to impair body mass regulation and thereby making it easier to regain the lost weight and develop over-weight when FR ends. However, it is unclear if th...Food restriction （FR） and refeeding （Re） have been suggested to impair body mass regulation and thereby making it easier to regain the lost weight and develop over-weight when FR ends. However, it is unclear if this is the case in small mammals showing seasonal forging behaviors. In the present study, energy budget, body fat and serum leptin level were measured in striped hamsters that were exposed to FR-Re. The effects of leptin on food intake, body fat and genes expressions of several hypothalamus neuropeptides were determined. Body mass, fat content and serum leptin level decreased during FR and then increased during Re. Leptin supplement significantly attenuated the increase in food intake during Re, decreased genes expressions of neuropepetide Y （NPY） and agouti-related protein （AgRP） of hypothalamus and leptin of white adipose tissue （WAT）. Hormone-sensitive lipase （HSL） gene expression of WAT increased in leptin-treated hamsters that were fed ad libitum, but decreased in FR-Re hamsters. This indicates that the adaptive regulation of WAT HSL gene expression may be involved in the mobilization of fat storage during Re, which partly contributes to the resistance to FR-Re-induced overweight. Leptin may be involved in the down regulations of hypothalamus orexigenic peptides gene expression and consequently plays a crucial role in controlling food intake when FR ends.展开更多
Magnetic resonance image （MRI） systems with a much higher magnetic flux density were developed and applied for potential use in medical diagnostic. Recently, much attention has been paid to the biological effects of...Magnetic resonance image （MRI） systems with a much higher magnetic flux density were developed and applied for potential use in medical diagnostic. Recently, much attention has been paid to the biological effects of static, strong magnetic fields （SMF）. With the 13 T SMF facility in the Institute of Plasma Physics, Chinese Academy of Sciences, the present study focused on the cellular effects of the SMF with 13 T on the cell viability and the cell cycle distribution in immortalized hamster cells, such as human-hamster hybrid （AL） cells, Chinese hamster ovary （CHO） cells, DNA double-strand break repair deficient mutant （XRS-5） cells, and human primary skin fibroblasts （AG1522） cells. It was found that the exposure of 13 T SMF had less effect on the colony formation in either nonsynchronized or synchronized AL cells. Moreover, as compared to non-exposed groups, there were slight differences in the cell cycle distribution no matter in either synchronized or nonsynchronized immortalized hamster ceils after exposure to 13 T SMF. However, it should be noted that the percentage of exposed AG1522 cells at G0/G1 phase was decreased by 10% as compared to the controls. Our data indicated that although 13 T SMF had minimal effects in immortalized hamster cells, the cell cycle distribution was slightly modified by SMF in human primary fibroblasts.展开更多
During the two-year pandemic of coronavirus disease 2019(COVID-19), its causative agent, severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), has been evolving. SARS-CoV-2 Delta, a variant of concern, has beco...During the two-year pandemic of coronavirus disease 2019(COVID-19), its causative agent, severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), has been evolving. SARS-CoV-2 Delta, a variant of concern, has become the dominant circulating strain worldwide within just a few months. Here, we performed a comprehensive analysis of a new B.1.617.2 Delta strain(Delta630) compared with the early WIV04 strain(WIV04) in vitro and in vivo, in terms of replication, infectivity, pathogenicity, and transmission in hamsters. When inoculated intranasally, Delta630 led to more pronounced weight loss and more severe disease in hamsters. Moreover, 40%mortality occurred about one week after infection with 10^(4)PFU of Delta630, whereas no deaths occurred even after infection with 10^(5)PFU of WIV04 or other strains belonging to the Delta variant. Moreover, Delta630outgrew over WIV04 in the competitive aerosol transmission experiment. Taken together, the Delta630 strain showed increased replication ability, pathogenicity, and transmissibility over WIV04 in hamsters. To our knowledge, this is the first SARS-CoV-2 strain that causes death in a hamster model, which could be an asset for the efficacy evaluation of vaccines and antivirals against infections of SARS-CoV-2 Delta strains. The underlying molecular mechanisms of increased virulence and transmission await further analysis.展开更多
AIM: To investigate the link between chronic biliary inflammation and carcinogenesis using hamster gallbladder epithelial cells. METHODS: Gallbladder epithelial cells were isolated from hamsters and cultured with a mi...AIM: To investigate the link between chronic biliary inflammation and carcinogenesis using hamster gallbladder epithelial cells. METHODS: Gallbladder epithelial cells were isolated from hamsters and cultured with a mixture of inflammatory cytokines including interleukin-1β,interferon-γ,and tumor necrosis factor-α. Inducible nitric oxide synthase (iNOS) expression,nitric oxide (NO) generation,and DNA damage were evaluated. RESULTS: NO generation was increased significantly following cytokine stimulation,and suppressed by an iNOS inhibitor. iNOS mRNA expression was demonstrated in the gallbladder epithelial cells during exposure to inflammatory cytokines. Furthermore,NO-dependent DNA damage,estimated by the comet assay,was significantly increased by cytokines,and decreased to control levels by an iNOS inhibitor. CONCLUSION: Cytokine stimulation induced iNOS expression and NO generation in normal hamster gallbladder epithelial cells,which was sufficient to cause DNA damage. These results indicate that NO-mediated genotoxicity induced by inflammatory cytokines through activation of iNOS may be involved in the process of biliary carcinogenesis in response to chronic inflammation of the biliary tree.展开更多
Nitric oxide is an important neuromodulator in the brain and is involved in the development of visual system. But it is not clear how nitric oxide and nitric oxide synthase （NOS） are involved in the developing visua...Nitric oxide is an important neuromodulator in the brain and is involved in the development of visual system. But it is not clear how nitric oxide and nitric oxide synthase （NOS） are involved in the developing visual cortex of rodents. Thus we examined the expression of NOS activity in the postnatal developing visual cortex of the golden hamster by using histochemical technique for NADPH-diaphorase （NADPH-d）. A heavily stained NADPH-d band was observed in the neuropil of the visual cortex. This NADPH-d band initially appeared in the cortical plate from the day of birth （P0） to postnatal day 4 （P4）. From P7 to P21, this band was confined to area 17 and migrated to the deeper layers Ill IV and V VI before it eventually disappeared at P28. Such developmental trends of the band correlated well with the process of formation and establishment of the geniculo-cortical projection patterns. Thus, the areal specific development of the band suggests that NOS is closely related to the cortical differentiation and synaptic formation of the primary visual cortex. On the other hand, monocular eye enucleation on P1 could not alter the appearance of this NADPH-d positive band, indicating a non-activity dependant role of NOS. In addition, differences in the laminar distributions and developmental sequence between the heavily and lightly stained NADPH-d positive neurons during development suggest that they play different roles in the development.展开更多
Objective: To investigate the roles of telomerase activity (TA) in relation to hamster buccal pouch tumor progression. Methods: male hamster were treated three times weekly with 0.5% of 7, 12-dimethyl-benzanthracene (...Objective: To investigate the roles of telomerase activity (TA) in relation to hamster buccal pouch tumor progression. Methods: male hamster were treated three times weekly with 0.5% of 7, 12-dimethyl-benzanthracene (DMBA) over a IS weeks experimental period. Hamsters were sacrificed at 3, 6, 9, 12 and 15 weeks after treatment. Telomerase activity of hamster buccal pouch tissue were measured along with the analyses of the formation of DMBA-induced hamster buccal pouch tumors. Results: DMBA-induced squamous cell carcinomas were found at the 6th week after dosing. Telomerase activity elevation began at the 3rd week and was increasing to a plateau at the 12th week. Conclusion: Our results show that telomerase activity in the target tissue may be detected at the early stage of the DMBA-induced hamster buccal pouch tumor formation and suggests that telomerase activity may be used as a biomarker for an early clinical detection of buccal pouch cancer.展开更多
Aberrant expression of carcinoembryonic antigen（CEA） is a common feature for multiple types of cancer,which makes it an attractive target for anticancer therapy.CAtin is a novel dual cancer-specific fusion protein,c...Aberrant expression of carcinoembryonic antigen（CEA） is a common feature for multiple types of cancer,which makes it an attractive target for anticancer therapy.CAtin is a novel dual cancer-specific fusion protein,composed of an anti-CEA single-chain disulfide-stabilized Fv antibody（scdsFv） and Apoptin,a tumor-specific apoptosis-inducing protein.Oral squamous cell carcinoma（OSCC） is an important healthcare problem in the clinic.To evaluate the anticancer effects of CAtin on OSCC,7,12-dimethylbenz[a]anthracene（DMBA） was used to induce oral carcinogenesis and premalignant lesions in the buccal pouch of Chinese hamster,and the antitumor effects of CAtin were determined in pre-cancer,cancer and post-operatative cancer models,respectively.The results show that the administration of CAtin delayed the malignant transformation of early stage cancerous lesions,inhibited the growth of established solid oral tumors and reduced the post-operatative relapse of lesions,with no significant systemic toxicity.This study demonstrates that CAtin may have potential for the treatment of OSCC,and the development of preventive strategies based on CAtin may offer a practical approach for the treatment of human oral tumors.展开更多
To prepare the PrP specific monoclonal antibodies （mAbs） that can be used for the detection of mammalian prions and study of pathogenesis of prion diseases. Methods Several BALB/c mice were immunized with recombinan...To prepare the PrP specific monoclonal antibodies （mAbs） that can be used for the detection of mammalian prions and study of pathogenesis of prion diseases. Methods Several BALB/c mice were immunized with recombinant hamster prion protein （HaPrP）. Three hybridoma cell lines designated as B7, B9, and B10, secreting monoclonal antibodies against HaPrP, were established by hybridoma technique. The mAbs reactivities were evaluated with ELISA, Western blot, and immunohistochemistry. Results The mAbs produced by these cell lines reacted well with different recombinant hamster PrP proteins. Western blot analyses showed that mAbs B7 and B9 reacted with PrP^Sc from the scrapie-infected animals after proteinase K digestion with three glycosylated forms. The mAbs exhibited cross-reactivity with various PrPc from several other mammalian species, including humans and cattles, lmmunohistochemistry assays confirmed that mAbs B7 and B9 could recognize not only extracellular but also intracellular PrPso. Conclusion The mAbs of prion protein are successfully generated by hybridoma technique and can be applied for the diagnosis of prion associated diseases.展开更多
基金National Key Research and Development Program for Young scientists,Grant/Award Number:2021YFF0703200National Natural Foundation Joint Fund for Regional Innovation and Development,Grant/Award Number:U21A20194+1 种基金National Natural Science Foundation of China,Grant/Award Number:32170540National Key Research and Development Program,Grant/Award Number:2022YFF0711005。
文摘Chinese hamster with Chinese characteristics is used in experiments,and it is of great value in the field of medical biology research.However,at present,there is no high-efficiency method for evaluating the genetic quality of Chinese hamsters.Here,we developed a novel Chinese hamster genetic quality detection system using single-nucleotide polymorphism(SNP)markers.To find SNP loci,we conducted whole genome sequencing on 24 Chinese hamsters.Then,we employed an SNP locus screening criterion that we set up previously and initially screened 214 SNP loci with wide genome distribution and high polymorphism level.Subsequently,we developed the SNP detection system using a multitarget region capture technique based on second-generation sequencing,and a 55 SNP panel for genetic evaluation of Chinese hamster populations was developed.PopGen.32.analysis results showed that the average effective allele number,Shannon index,observed heterozygosity,expected heterozygosity,average heterozygosity,polymorphism information,and other genetic parameters of Chinese hamster population A were higher than those in population B.Using scientific screening and optimization,we successfully developed a novel Chinese hamster SNP genetic detection system that can efficiently and accurately analyze the genetic quality of the Chinese hamster population.
基金supported by the National Natural Science Foundation of Jiangsu Province(BE20197310 to J-M.L.)the National Key R&D Program of China(2021YFF0702500 to J-M.L.and A-M.S.,and the Start-up Funding of Scientific Researches for Postdoc in Guangzhou,Guangdong Province to H-F.L.).
文摘Being widespread across the globe,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)keeps evolving and generating new variants and continuously poses threat to public health,especially to the population with chronic comorbidities.Diabetes mellitus is one of high-risk factors for severe outcome of coronavirus disease 2019(COVID-19).Establishment of animal models that parallel the clinical and pathological features of COVID-19 complicated with diabetes is thus highly essential.Here,in this study,we constructed leptin receptor gene knockout hamsters with the phenotype of diabetes mellitus(db/db),and revealed that the diabetic hamsters were more susceptible to SARS-CoV-2 and its variants than wild-type hamsters.SARS-CoV-2 and its variants induced a stronger immune cytokine response in the lungs of diabetic hamsters than in wild-type hamsters.Comparative histopathology analyses also showed that infection of SARS-CoV-2 and the variants caused more severe lung tissue injury in diabetic hamsters,and may induce serious complications such as diabetic kidney disease and cardiac lesions.Our findings demonstrated that despite the decreased respiratory pathogenicity,the SARS-CoV-2 variants were still capable of impairing other organs such as kidney and heart in diabetic hamsters,suggesting that the risk of evolving SARS-CoV-2 variants to diabetic patients should never be neglected.This hamster model may help better understand the pathogenesis mechanism of severe COVID-19 in patients with diabetes.It will also aid in development and testing of effective therapeutics and prophylactic treatments against SARS-CoV-2 variants among these high-risk populations.
基金Student Research Training Program,Grant/Award Number:2022104391282Shandong Natural Science Foundation,Grant/Award Number:ZR2019MH021National Natural Science Foundation of China,Grant/Award Number:81970385。
文摘Background:Thromboelastography(TEG)is a widely utilized clinical testing method for real-time monitoring of platelet function and the thrombosis process.Lipid metab-olism disorders are crucial risk factors for thrombosis.The lipid metabolism charac-teristics of hamsters resemble those of humans more closely than mice and rats,and their relatively large blood volume makes them suitable for studying the mechanisms of thrombosis related to plasma lipid mechanisms.Whole blood samples from golden Syrian hamsters and healthy humans were obtained following standard clinical pro-cedures.TEG was employed to evaluate coagulation factor function,fibrinogen(Fib)function,platelet function,and the fibrinolytic system.Methods:The whole blood from hamster or healthy human was isolated following the clinical procedure,and TEG was employed to evaluate the coagulation factor func-tion,Fib function,platelet function,and fibrinolytic system.Coagulation analysis used ACLTOP750 automatic coagulation analysis pipeline.Blood routine testing used XN-2000 automatic blood analyzer.Results:TEG parameters revealed that hamsters exhibited stronger coagulation fac-tor function than humans(reaction time[R],p=0.0117),with stronger Fib function(alpha angle,p<0.0001;K-time[K],p<0.0001).Platelet function did not differ signifi-cantly(maximum amplitude[MA],p=0.077).Hamsters displayed higher coagulation status than humans(coagulation index[CI],p=0.0023),and the rate of blood clot dissolution in hamsters differed from that in humans(percentage lysis 30 min after MA,p=0.02).Coagulation analysis parameters indicated that prothrombin time(PT)and activated partial thromboplastin time(APTT)were faster in hamsters than in hu-mans(PT,p=0.0014;APTT,p=0.03),whereas the Fib content was significantly lower in hamsters than in humans(p<0.0001).No significant difference was observed in thrombin time(p=0.1949).Conclusions:In summary,TEG could be used to evaluate thrombosis and bleeding parameters in whole blood samples from hamsters.The platelet function of hamsters closely resembled that of humans,whereas their coagulation function was signifi-cantly stronger.
基金supported by several key projects,the Medical and Health Science and Technology Innovation Project of the Chinese Academy of Medical Sciences(CIFMS,2016-I2M-2-001)the National Resource Center for Non-Human Primates,Major Science and Technology Special Projects in Yunnan Province,Kunming Science and Technology Innovation and Service Capacity Enhancement Program Key Projects(2016-2-R-07674)+3 种基金the CAMS Innovation Fund for Medical Sciences(CIFMS,2018-I2M-3-002 and 2021-I2M-1-024)the National Key R&D Project of China(2021YFF0702804)Peking Union Medical College-Central University Basic Scientific Research Business Fee(Project number.:3332023079)Yunnan Province Applied Basic Research Special Project-General Project(project number:202401CF070048,202301AT070367).
文摘Coxsackievirus B3(CVB3)is the pathogen causing hand,foot and mouth disease(HFMD),which manifests across a spectrum of clinical severity from mild to severe.However,CVB3-infected mouse models mainly demonstrate viral myocarditis and pancreatitis,failing to replicate human HFMD symptoms.Although several enteroviruses have been evaluated in Syrian hamsters and rhesus monkeys,there is no comprehensive data on CVB3.In this study,we have first tested the susceptibility of Syrian hamsters to CVB3 infection via different routes.The results showed that Syrian hamsters were successfully infected with CVB3 by intraperitoneal injection or nasal drip,leading to nasopharyngeal colonization,acute severe pathological injury,and typical HFMD symptoms.Notably,the nasal drip group exhibited a longer viral excretion cycle and more severe pathological damage.In the subsequent study,rhesus monkeys infected with CVB3 through nasal drips also presented signs of HFMD symptoms,viral excretion,serum antibody conversion,viral nucleic acids and antigens,and the specific organ damages,particularly in the heart.Surprisingly,there were no significant differences in myocardial enzyme levels,and the clinical symptoms resembled those often associated with common,mild infections.In summary,the study successfully developed severe Syrian hamsters and mild rhesus monkey models for CVB3-induced HFMD.These models could serve as a basis for understanding the disease pathogenesis,conducting pre-trial prevention and evaluation,and implementing post-exposure intervention.
文摘In order to understand the effect of gradual changes in photoperiod on immune function, adult female Siberian hamsters (Phodopus sungorus) were randomly divided into the control group (12L:12D, Con, n = 11) and the shortening day length group (SD, n = 11), in which day length was reduced from 12:12 h to 8:16 h light-dark cycle at the pace of half an hour every week. Meanwhile the winter immunoenhancement hypothesis, which holds that animals’ immune function would be enhanced in winter or winter-like conditions, was tested. Gradual shortening day length had no effect on body mass and body composition including wet carcass mass, the subcutaneous, retroperitoneal, mesenteric and total body fat masses in Siberian hamsters. The masses of liver and small intestine with contents were higher in the SD group than in the Con group, however other organ masses such as brain, heart, kidney and so on did not differ between the two groups. Phytohemagglutinin (PHA) response after 24 h of PHA injection was enhanced by the shortening photoperiod, which supported the winter immunoenhancement hypothesis. The masses of spleen and thymus, white blood cells, bacteria killing capacity indicative of innate immunity were not affected, which did not support this hypothesis. In summary, gradually decrease in day length increased cellular immunity, but had no effect on other immunological parameters in Siberian hamsters.
基金National Natural Science Foundation of China (NSFC)31520103909 and.91739105 to G.Liu,81770449 to Y.Wang。
文摘Hypertriglyceridemia(HTG)often accompanies diabetes and is considered a risk factor for diabetic vascular complications.However,inducing diabetic HTG typically requires high-fat diets in certain animal models.Leveraging our newly developed LDL receptor knockout hamster model,which exhibits features akin to human lipid metabolism,we sought to determine whether these animals would develop HTG without dietary manipulations in diabetes.Diabetes was induced via intraperitoneal injection of STZ in wild type and heterozygous LDL receptor deficient hamsters.Blood glucose,triglyceride,and cholesterol were measured over 60 days.Plasma TG clearance was determined via olive oil gavage.The effect of insulin on diabetic HTG was assessed on Day 60 post-diabetes induction.Blood glucose increased over threefold,while plasma insulin decreased to 30%of controls after STZ injection in both wild type and heterozygous hamsters by Day 7,remaining stable for 60 days.Plasma TG in wild-type hamsters remained unchanged at Day 7 post-STZ injection but increased slightly thereafter.Conversely,heterozygous hamsters exhibited severe HTG by Day 7 until the end of the study.Olive oil gavage revealed much slower plasma triglyceride clearance in heterozygous hamsters compared to WT animals,despite significantly reduced lipoprotein lipase activity in post-heparin plasma in both animals.Hyperglycemia and HTG in heterozygous hamsters were reversed to pre-diabetic levels following intraperitoneal insulin administration.In conclusion,severe HTG in diabetic heterozygous LDL receptor deficient hamsters developed spontaneously and was insulin-dependent.Thus,this hamster model holds promise for effectively studying the complications associated with human diabetic HTG.
基金Acknowledgment This work was supported by a grant from the National Nature Science Foundation of China （No. 39970374）. The authors wish to thank Professor Yi-Pong Hu, Second Military Medical University of China, for his kindness in providing us the recombinant plasmid （pBR322-HBV）. We wish to thank Mr. Michael Talion of Shantou University Medical College, English Language Training Section for his assistance in proofreading this manuscript. We gratefully acknowledge the support of the leaders of Shantou University Medical College.
文摘Aim： To detect the expression of hepatitis B virus （HBV） genes （HB S and C genes） in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization （IVF） technique. Methods： Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method. Polymerase chain reaction （PCR） was used to detect HB S and pre-Core/Core （pre-C/C） coding genes both in one- and two-cell embryos. Reverse transcription-PCR （RT-PCR） analysis was used to study the expression of the two genes. Fluorescence in situ hybridization （FISH） analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome. Results： Both HB S and pre-C/C coding genes are present and transcribed in one- and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences. Conclusion： Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells. These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line.
基金supported by 2003 Nutrition Research Fund of Chinese Nutrition Society
文摘Objective To examine the effects of chlorogenic acid （CGA） on lipid and glucose metabolism under a high dietary fat burden and to explore the possible role of peroxisome proliferator-activated receptor-α （PPAR-α） in these effects. Methods Twenty male golden hamsters were randomly divided into CGA treatment group （n=10, given peritoneal injection of CGA solution prepared with PBS, 80 mg CGA/kg body weight daily）, and control group （n=10, given PBS i.p. at the average volume of the treatment group）. Animals in both groups were given 15% high fat diet. Eight weeks after treatment with CGA, the level of biochemical parameters in fasting serum and tissues and the expression of hepatic mRNA and protein PPAR-α were determined. Results Eight weeks after treatment with CGA, the levels of fasting serum triglyceride （TG）, free fatty acid （FFA）, total cholesterol （TC）, low density lipoprotein cholesterol （LDL-C）, high density lipoprotein cholesterol （HDL-C）, glucose （FSG）, and insulin （FSI） were significantly lower in the GGA treatment group than in the control group. CGA also led to higher activity of hepatic lipase （HL） lower contents of TG and FFA in liver, and lower activity of lipoprotein lipase （LPL） in skeletal muscle. Furthermore, CGA significantly elevated significantly elevated the expression level of mRNA and protein expression in hepatic PPAR-α. Conclusion CGA can modify lipids and glucose metabolism, which may be attributed to PPAR-α facilitated lipid clearance in liver and improved insulin sensitivity.
基金supported by grants from the highly distinguished Oncology Subject Foundation of Colleges in Hebei Province
文摘Aim To investigate the role of the Chinese herbal medicine Xianhuayin on the reversal of 7,12-dimethylbenz[a]anthracene （DMBA）-induced premalignant mucosal lesions in the oral buccal pouch of golden hamsters. Methodology The animals were randomly divided into a non-diseased control group （n=5） and an experimental group including 50 animals in which the buccal mucosa had been painted with DMBA （0.5% in acetone） to generate an oral mucosa premalignant lesion. Animals in the experi- mental group were further divided into Xianhuayin-treated group （n=30）, untreated prem＇alignant lesion group （n=10） and normal saline （NS）-treated group （n=10）. The cheek （buccal） pouch mucosa of the golden hamsters in each group was observed with light and electron microscopy eight weeks after intragastric administration with NS or Xianhuayin. Results In the non-diseased control group, the buccal mucosa was keratinized and stratified squamous epithelium under a light microscope. In the untreated premalignant lesion group, variable degrees of epithelial dysplasia was observed. The irregular epithelial mucosa gradually became distinct in the Xianhuayin-treated group. Scanning electronic microscopic （SEM） analysis showed that surface of the cells exhibited honeycomb structures in the hamster of untreated- group. The cells were morphologically irregular, overlapped and loosened in the untreated premalignant lesion group. Most of the cell surface exhibited honeycomb structure in the Xianhuayin-treated group. Transmission electronic micro- scopic （TEM） analysis showed that buccal mucosal epithelial cells were morphologically regular in the non-diseased control group. Desmosomes and tonofibrils were reduced and the nucleus was morphologically irregular in the untreated premalignant lesion group. In the Xianhuayin-treated group, the widening intercellular gap was gradually reduced, desmosomes and the cells becoming morphologically regular. No significant difference was observed between the hamsters in NS-treated group and those in the untreated premalignant lesion group. Significant therapeutic efficacy was observed in the group receiving Xianhuayin. Conclusion Xianhuayin is effective in the reversal of DMBA-induced premalignant lesions in the buccal pouch of golden hamsters.
文摘AIM： TO investigate the effects of ursodeoxycholic acid （UDCA） on chenodeoxycholic acid （CDCA）-induced liver injury in hamsters, and to elucidate a correlation between liver injury and bile acid profiles in the liver.METHODS： Liver injury was induced in hamsters by administration of 0.5% （w/w） CDCA in their feed for 7 d. UDCA （50 mg/kg and 150 mg/kg） was administered for the last 3 d of the experiment.RESULTS： At the end of the experiment, serum alanine aminotransferase （ALl） increased more than 10 times and the presence of liver injury was confirmed histologically. Marked increase in bile acids was observed in the liver. The amount of total bile acids increased approximately three-fold and was accompanied by the increase in hydrophobic bile acids, CDCA and lithocholic acid （LCA）. UDCA （50 mg/kg and 150 mg/kg） improved liver histology, with a significant decrease （679.3 ±77.5 U/L vs 333.6 ± 50.4 U/L and 254.3 ±35.5 U/ L, respectively, P 〈 0.01） in serum ALT level. UDCA decreased the concentrations of the hydrophobic bile acids, and as a result, a decrease in the total bile acid level in the liver was achieved.CONCLUSION： The results show that UDCA improves oral CDCA-induced liver damage in hamsters. The protective effects of UDCA appear to result from a decrease in the concentration of hydrophobic bile acids, CDCA and LCA, which accumulate and show the cytotoxicity in the liver.
基金supported by a grant from Kyung Hee University Research(20071618)
文摘BACKGROUND:Our earlier study with cultured gallbladder epithelial cells demonstrated that statins(HMG-CoA reductase inhibitors)activate the expression of PPARαand PPARγ, consequently blocking the production of pro-inflmmatory cytokines.The present study used hamsters to investigate the effects of pavastatin on PPARα/PPARγexpression in the liver and gallbladder epithelium,and to determine whether pravastatin suppresses cholesterol crystal formation in the gallbladder. METHODS:A total of 40 Golden Syrian male hamsters(4 weeks old)were randomly assigned to four groups(basal diet control; basal diet+pavastatin;high cholesterol diet;high cholesterol diet+pravastatin).All hamsters were 11 weeks old at the end of the experiment.The liver,gallbladder and bile were harvested. Immunohistochemical staining and Western blotting for PPARαand PPARγwere performed in the liver and gallbladder. A drop of fresh bile was examined for cholesterol crystals under a microscope. RESULTS:In the gallbladder and liver of the hamsters, pravastatin activated the PPARαand PPARγexpression of gallbladder epithelial cells and hepatocytes,and particularly the response of PPARγwas much stronger than that of PPARα. Pravastatin suppressed the formation of cholesterol gallstones or crystals in the gallbladder. CONCLUSION:Pravastatin is an effective medication to activate PPARs(especially PPARγ)in the liver and the gallbladder epithelium of hamsters,and contributes to the prevention of gallstone formation.
文摘The immotile testicular mammalian spermatozoon gets transformed into a motile spermatozoon during ＇epididymal maturation＇. During this process, the spermatozoa transit from the caput to the cauda epididymis and undergo a number of distinct morphological, biophysical and biochemical changes, including changes in protein composition and protein modifications, which may be relevant to the acquisition of motility potential. The present proteome-based study of the hamster epididymal spermatozoa of caput and cauda led to the identification of 113 proteins spots using Matrix- assisted laser desorption/ionization tandem mass spectrometry （MALDI-MS/MS） analysis. Comparison of these 113 protein spots indicated that 30 protein spots （corresponding to 20 proteins） were significantly changed in intensity. Five proteins were increased and eleven were decreased in intensity in the cauda epididymal spermatozoa. In addition, two proteins, glucose-regulated protein precursor （GRP78） and tumor rejection antigen （GP96）, were unique to the caput epididymal spermatozoa, while one protein, fibrinogen-like protein 1, was unique to cauda epididymal spermatozoa. A few of the five proteins, which increased in intensity, were related to sperm metabolism and ATP production during epididymal maturation. The changes in intensity of a few proteins such as ERp57, GRP78, GP96, Hsp60, Hsp70, and dihydrolipoamide S-acetyltransferase were validated by immunoblotting. The present study provides a global picture of the changes in protein composition occurring during hamster sperm epididymal maturation, besides being the first ever report on the proteome of hamster spermatozoa.
基金Foundation items： This work was supported by the National Natural Science Foundation of China （31270458, 31070367） and partly sup- ported by the grant from Zhejiang Province （pd2013374）
文摘Food restriction （FR） and refeeding （Re） have been suggested to impair body mass regulation and thereby making it easier to regain the lost weight and develop over-weight when FR ends. However, it is unclear if this is the case in small mammals showing seasonal forging behaviors. In the present study, energy budget, body fat and serum leptin level were measured in striped hamsters that were exposed to FR-Re. The effects of leptin on food intake, body fat and genes expressions of several hypothalamus neuropeptides were determined. Body mass, fat content and serum leptin level decreased during FR and then increased during Re. Leptin supplement significantly attenuated the increase in food intake during Re, decreased genes expressions of neuropepetide Y （NPY） and agouti-related protein （AgRP） of hypothalamus and leptin of white adipose tissue （WAT）. Hormone-sensitive lipase （HSL） gene expression of WAT increased in leptin-treated hamsters that were fed ad libitum, but decreased in FR-Re hamsters. This indicates that the adaptive regulation of WAT HSL gene expression may be involved in the mobilization of fat storage during Re, which partly contributes to the resistance to FR-Re-induced overweight. Leptin may be involved in the down regulations of hypothalamus orexigenic peptides gene expression and consequently plays a crucial role in controlling food intake when FR ends.
基金supported by National Natural Science Foundation of China (Nos. 30570442, 10225526)Hundred Talents Program of The Chinese Academy of Sciences and Foundation of President, of The Hefei Institutes of Physical Sciences, CAS
文摘Magnetic resonance image （MRI） systems with a much higher magnetic flux density were developed and applied for potential use in medical diagnostic. Recently, much attention has been paid to the biological effects of static, strong magnetic fields （SMF）. With the 13 T SMF facility in the Institute of Plasma Physics, Chinese Academy of Sciences, the present study focused on the cellular effects of the SMF with 13 T on the cell viability and the cell cycle distribution in immortalized hamster cells, such as human-hamster hybrid （AL） cells, Chinese hamster ovary （CHO） cells, DNA double-strand break repair deficient mutant （XRS-5） cells, and human primary skin fibroblasts （AG1522） cells. It was found that the exposure of 13 T SMF had less effect on the colony formation in either nonsynchronized or synchronized AL cells. Moreover, as compared to non-exposed groups, there were slight differences in the cell cycle distribution no matter in either synchronized or nonsynchronized immortalized hamster ceils after exposure to 13 T SMF. However, it should be noted that the percentage of exposed AG1522 cells at G0/G1 phase was decreased by 10% as compared to the controls. Our data indicated that although 13 T SMF had minimal effects in immortalized hamster cells, the cell cycle distribution was slightly modified by SMF in human primary fibroblasts.
基金supported by China Natural Science Foundation (82150201)
文摘During the two-year pandemic of coronavirus disease 2019(COVID-19), its causative agent, severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), has been evolving. SARS-CoV-2 Delta, a variant of concern, has become the dominant circulating strain worldwide within just a few months. Here, we performed a comprehensive analysis of a new B.1.617.2 Delta strain(Delta630) compared with the early WIV04 strain(WIV04) in vitro and in vivo, in terms of replication, infectivity, pathogenicity, and transmission in hamsters. When inoculated intranasally, Delta630 led to more pronounced weight loss and more severe disease in hamsters. Moreover, 40%mortality occurred about one week after infection with 10^(4)PFU of Delta630, whereas no deaths occurred even after infection with 10^(5)PFU of WIV04 or other strains belonging to the Delta variant. Moreover, Delta630outgrew over WIV04 in the competitive aerosol transmission experiment. Taken together, the Delta630 strain showed increased replication ability, pathogenicity, and transmissibility over WIV04 in hamsters. To our knowledge, this is the first SARS-CoV-2 strain that causes death in a hamster model, which could be an asset for the efficacy evaluation of vaccines and antivirals against infections of SARS-CoV-2 Delta strains. The underlying molecular mechanisms of increased virulence and transmission await further analysis.
文摘AIM: To investigate the link between chronic biliary inflammation and carcinogenesis using hamster gallbladder epithelial cells. METHODS: Gallbladder epithelial cells were isolated from hamsters and cultured with a mixture of inflammatory cytokines including interleukin-1β,interferon-γ,and tumor necrosis factor-α. Inducible nitric oxide synthase (iNOS) expression,nitric oxide (NO) generation,and DNA damage were evaluated. RESULTS: NO generation was increased significantly following cytokine stimulation,and suppressed by an iNOS inhibitor. iNOS mRNA expression was demonstrated in the gallbladder epithelial cells during exposure to inflammatory cytokines. Furthermore,NO-dependent DNA damage,estimated by the comet assay,was significantly increased by cytokines,and decreased to control levels by an iNOS inhibitor. CONCLUSION: Cytokine stimulation induced iNOS expression and NO generation in normal hamster gallbladder epithelial cells,which was sufficient to cause DNA damage. These results indicate that NO-mediated genotoxicity induced by inflammatory cytokines through activation of iNOS may be involved in the process of biliary carcinogenesis in response to chronic inflammation of the biliary tree.
基金the Fundamental Research Funds for the Central Universities,No.21609101the National Basic Research Program of China (973 Program),No.2011CB707501
文摘Nitric oxide is an important neuromodulator in the brain and is involved in the development of visual system. But it is not clear how nitric oxide and nitric oxide synthase （NOS） are involved in the developing visual cortex of rodents. Thus we examined the expression of NOS activity in the postnatal developing visual cortex of the golden hamster by using histochemical technique for NADPH-diaphorase （NADPH-d）. A heavily stained NADPH-d band was observed in the neuropil of the visual cortex. This NADPH-d band initially appeared in the cortical plate from the day of birth （P0） to postnatal day 4 （P4）. From P7 to P21, this band was confined to area 17 and migrated to the deeper layers Ill IV and V VI before it eventually disappeared at P28. Such developmental trends of the band correlated well with the process of formation and establishment of the geniculo-cortical projection patterns. Thus, the areal specific development of the band suggests that NOS is closely related to the cortical differentiation and synaptic formation of the primary visual cortex. On the other hand, monocular eye enucleation on P1 could not alter the appearance of this NADPH-d positive band, indicating a non-activity dependant role of NOS. In addition, differences in the laminar distributions and developmental sequence between the heavily and lightly stained NADPH-d positive neurons during development suggest that they play different roles in the development.
文摘Objective: To investigate the roles of telomerase activity (TA) in relation to hamster buccal pouch tumor progression. Methods: male hamster were treated three times weekly with 0.5% of 7, 12-dimethyl-benzanthracene (DMBA) over a IS weeks experimental period. Hamsters were sacrificed at 3, 6, 9, 12 and 15 weeks after treatment. Telomerase activity of hamster buccal pouch tissue were measured along with the analyses of the formation of DMBA-induced hamster buccal pouch tumors. Results: DMBA-induced squamous cell carcinomas were found at the 6th week after dosing. Telomerase activity elevation began at the 3rd week and was increasing to a plateau at the 12th week. Conclusion: Our results show that telomerase activity in the target tissue may be detected at the early stage of the DMBA-induced hamster buccal pouch tumor formation and suggests that telomerase activity may be used as a biomarker for an early clinical detection of buccal pouch cancer.
基金Supported by the National Natural Science Foundation of China(Nos.30870347,81101140)the Youth Foundation of Laboratory Animal Center of Academy of Military Medical Sciences of China(No.QN2010-001)the National Science Foundation for Post-doctoral Scientits of China(No.20100481057)
文摘Aberrant expression of carcinoembryonic antigen（CEA） is a common feature for multiple types of cancer,which makes it an attractive target for anticancer therapy.CAtin is a novel dual cancer-specific fusion protein,composed of an anti-CEA single-chain disulfide-stabilized Fv antibody（scdsFv） and Apoptin,a tumor-specific apoptosis-inducing protein.Oral squamous cell carcinoma（OSCC） is an important healthcare problem in the clinic.To evaluate the anticancer effects of CAtin on OSCC,7,12-dimethylbenz[a]anthracene（DMBA） was used to induce oral carcinogenesis and premalignant lesions in the buccal pouch of Chinese hamster,and the antitumor effects of CAtin were determined in pre-cancer,cancer and post-operatative cancer models,respectively.The results show that the administration of CAtin delayed the malignant transformation of early stage cancerous lesions,inhibited the growth of established solid oral tumors and reduced the post-operatative relapse of lesions,with no significant systemic toxicity.This study demonstrates that CAtin may have potential for the treatment of OSCC,and the development of preventive strategies based on CAtin may offer a practical approach for the treatment of human oral tumors.
文摘To prepare the PrP specific monoclonal antibodies （mAbs） that can be used for the detection of mammalian prions and study of pathogenesis of prion diseases. Methods Several BALB/c mice were immunized with recombinant hamster prion protein （HaPrP）. Three hybridoma cell lines designated as B7, B9, and B10, secreting monoclonal antibodies against HaPrP, were established by hybridoma technique. The mAbs reactivities were evaluated with ELISA, Western blot, and immunohistochemistry. Results The mAbs produced by these cell lines reacted well with different recombinant hamster PrP proteins. Western blot analyses showed that mAbs B7 and B9 reacted with PrP^Sc from the scrapie-infected animals after proteinase K digestion with three glycosylated forms. The mAbs exhibited cross-reactivity with various PrPc from several other mammalian species, including humans and cattles, lmmunohistochemistry assays confirmed that mAbs B7 and B9 could recognize not only extracellular but also intracellular PrPso. Conclusion The mAbs of prion protein are successfully generated by hybridoma technique and can be applied for the diagnosis of prion associated diseases.
