Two new oligopeptides, Asterin A and B, have been isolated from the roots of Aster tataricus L. f., and their structures were elucidated on the basis of spectroscop- ic, chemical and enzymatic methods.
A highly sensitive HPLC method for the detection of amino acids and oligopeptides with 9-acridine formyl chloride by pre-column fluorescence derivatization has been developed. Glycine, glycylglycine, histidine, trigly...A highly sensitive HPLC method for the detection of amino acids and oligopeptides with 9-acridine formyl chloride by pre-column fluorescence derivatization has been developed. Glycine, glycylglycine, histidine, triglycine and glutathione were separated on a reversed-phase C-18 column with methanol-water-triethylamine eluent, derivatization and chromatographic conditions were optimized. The five derivatives were eluted in 28 min with a good reproducibility. Linear range of the calibration graph was 0.08-260 nmol/ml(-1). The relative standard deviations(n=6) are < 5%. Detection limits (signal-to-noise ratio=3) for the five derivatives are 20-40 fmol.展开更多
A series of novel gossypol derivatives were synthesized and screened for their in vitro anti-HIV- 1I activity. The results showed that replacing the aldehyde groups of gossypol with certain oligopeptides and Dglucosam...A series of novel gossypol derivatives were synthesized and screened for their in vitro anti-HIV- 1I activity. The results showed that replacing the aldehyde groups of gossypol with certain oligopeptides and Dglucosamine not only reduced the cytotoxicity of gossypol derivatives but also enhanced their antiviral activity against HIV-1. Interestingly, D-glucosamine derivative of gossypol that lacked the COONa group also exhibited the same potent anti-HIV-1 activity as oligopeptide derivatives with the COONa group. These compounds blocked the entry of HIV-1ⅢB into target cell. which was similar to T20. Furthermore, the molecular docking analysis rationalized their anti-HIV-1 activity. The results also implied that certain oligopeptides and D-glucosamine were important moities to prepare gossypol derivatives as HIV- 1 entry inhibitors besides certain amino acids.展开更多
We previously investigated the physiological effect of an ethanol extract of fermented soymilk on rats and clarified that this extract modulated their hepatic lipid metabolism. Although the soy isoflavones and oligope...We previously investigated the physiological effect of an ethanol extract of fermented soymilk on rats and clarified that this extract modulated their hepatic lipid metabolism. Although the soy isoflavones and oligopeptides are representative functional components of the ethanol extract, it remained unclear whether these substances share a role in lipid metabolism modulation. Therefore, we attempted to clarify the effects of isoflavones and oligopeptides in lactic acid-fermented soymilk on lipid metabolism-related gene expression in rats and HepG2 cells. The fermented soymilk extract had a higher isoflavone aglycone content than the soymilk extract. Sevenweek-old male Sprague-Dawley rats were fed an AIN-93G diet, a diet plus 70% soymilk ethanol extract, or a diet plus 70% fermented soymilk ethanol extract for 5 weeks. Although both the soymilk and fermented soymilk ethanol extracts did not significantly affect plasma and hepatic lipid profiles, the expression levels of the genes encoding CYP7a1 and SREBP-2 were significantly upregulated in the livers of rats fed with the fermented soymilk extract. Whereas isoflavone aglycones upregulated CYP7a1-encoding gene expression in HepG2, oligopeptides in soymilk and fermented soymilk downregulated this expression. Oligopeptides in fermented soymilk downregulated the expression stronger than that observed with soymilk. On the other hand, no significant change in FAS expression was observed in the livers of rats fed the fermented soymilk extract. Although isoflavone aglycones did not affect FAS expression in HepG2 cells, oligopeptides in fermented soymilk downregulated FAS expression. The downregulation of FAS with oligopeptides from fermented soymilk was stronger than that from soymilk. In the present animal experiment, the effect on reduction of fat synthesis was not found because of insufficient amount of peptides derived from digestion of soy protein. These results suggest that isoflavone aglycones increase CYP7a1 gene expression, whereas oligopeptides decrease FAS expression. Isoflavone glycosides and proteins in soymilk were converted to isoflavone aglycones and oligopeptides by lactic acid fermentation, respectively, and these functional components independently improved the lipid metabolism. In the present study, it was found that isoflavone aglycones and oligopeptides in fermented soymilk differentially regulate hepatic lipid metabolism-related gene expression. Therefore, the consumption of fermented soymilk containing isoflavone aglycones and soy oligopeptides might prevent dyslipidemia more effectively than that of any other soy food. Fermented soymilk is a superior functional food modulating lipid metabolism.展开更多
For bone regenerative engineering,it is a promising method to form skeletal tissues differentiating from human bone morrow mesenchyme stem cells(hBMSCs).However,it is still a critical challenge to efficiently control ...For bone regenerative engineering,it is a promising method to form skeletal tissues differentiating from human bone morrow mesenchyme stem cells(hBMSCs).However,it is still a critical challenge to efficiently control ostogenesis and clearly reveal the influence factor.To this end,the fluorescent gold nanodots(Au NDs) with highly negative charges as osteogenic induction reagent are successfully synthesized,which display better than commercial osteogenic induction medium through the investigations of ALP activity(2.5 folds) and cytoskeleton staining(1.5 folds).Two kinds of oligopeptides with different bio-structures(cysteine,Cys and glutathione,GSH) are selected for providing surficial charges on Au NDs.It is revealed that Au-Cys with more negative charges(-51 mV) play better role than Au-GSH(-19 mV) in osteogenic differentiation,when both of them have same size(~2 nm),sphere shape and show similar cell uptake amount.To explore deeply,osteogenesis related signaling pathways are monitored,revealing that the enhancement of osteogenic differentiation was through autophagy signaling pathway triggered by Au-Cys.And the promotion of highly negative charges in osteogenic diffe rentiation was further proved via sliver nanodots(Ag NDs,Ag-Cys and Ag-GSH) and carbon nanodots(CDs,Cys-CDs and GSH-CDs).This work indicates part of insights during hBMSCs differentiation and provides a novel strategy in osteogenic differentiation process.展开更多
DAPTMGY(DTY)is an oligopeptide derived from marine microalgae with proven potential to combat oxidative stress in previous research.The composition,ordering,and active sites of amino acids play a key role in activity ...DAPTMGY(DTY)is an oligopeptide derived from marine microalgae with proven potential to combat oxidative stress in previous research.The composition,ordering,and active sites of amino acids play a key role in activity studies and are also the research trends in recent years.As an oligopeptide with a molecular weight of less than 1000 Da,DTY is of great significance to explore the active site and structure-activity relationship.This study used quantum mechanics to optimize DTY’s structure and predict the active site through molecular orbits,energy,and charge.In addition,an LPS-treated HUVEC cell was established as an oxidative-stress model.DTY could reduce mitochondrial oxidative stress and inhibit ROS production by enhancing the antioxidant enzymes SOD,GPX,and HO-1.Moreover,it was confirmed to inhibit inflammation and apoptosis through the NF-κB and MAPK signaling pathways.Lastly,the correlation of the oligopeptide DTY’s active site and antioxidative-stress activity was verified by molecular docking,showing that hydrogen bonding is the main force,which was also the main factor for antioxidant activity.展开更多
High Fischer ratio oligopeptides(HFROs)are a group of oligopeptides containing high levels of branched-chain amino acids(BCAA)and low levels of aromatic amino acids(AAA).HFROs have received a lot of attention as they ...High Fischer ratio oligopeptides(HFROs)are a group of oligopeptides containing high levels of branched-chain amino acids(BCAA)and low levels of aromatic amino acids(AAA).HFROs have received a lot of attention as they are believed to have significant physiological activities,including antioxidant,liver damage repair,anti-fatigue,anti-tumor and energy supply to the body.HFROs are available from a wide range of sources and both plant and animal proteins can be used to prepare HFROs but the physiological tolerability and rejection of special populations needs to be considered.Enzymatic hydrolysis is the most common method for the preparation of HFROs,but optimization of the separation and purification process is still needed in the future.Diseases caused by disruptions in the balance of BCAA and AAA in the blood,such as hepatic encephalopathy,can be treated by supplementing HFROs with drugs or food.In addition,HFROs are able to reduce fatigue feedback and assist in the treatment of phenylketonuria at the molecular nutrient level.The aim of this review is to review recent research on HFROs and provide new perspectives on the high value use of crops and the development of novel functional and special medical purpose foods.展开更多
Background:Liver cancer as the main leading cancer has caused heavy burdens globally.The prognosis of liver cancer is closely related with postoperative nutrition support.Corn oligopeptides(COPs)are protein hydrolysat...Background:Liver cancer as the main leading cancer has caused heavy burdens globally.The prognosis of liver cancer is closely related with postoperative nutrition support.Corn oligopeptides(COPs)are protein hydrolysates produced by enzymatic treatments,which have shown potential bioactivities,such as inhibiting angiotensin I-converting enzyme,resisting lipid peroxidation and anti-oxidant.However,the correlation between COPs and liver cancer patients is still unknown and the potential mechanism of COPs on liver cancer is unclear as well.The aim of this study was to assess effects of 7-day intervention of COPs after surgery on liver function and serum metabolic profiles of liver cancer patients.Methods:Patients were assigned into COPs intervention group(n=50)and control group(n=91)for 7 days.Investigations were scheduled at 1st day and 7th day after liver resection surgery respectively,mainly including anthropometric,biochemical indexes and liquid chromatography-mass spectrometry(LC/MS)analysis.Results:Seven-day supplementation of COPs on early post-surgery liver cancer patients down-regulated levels of alanine aminotransferase,aspartate aminotransferase,total bilirubin,direct bilirubin and up-regulated prothrombin time activity and prealbumin levels.LC/MS analysis revealed metabolic signatures including regulation of 16 metabolites,which was closely related with two metabolic pathways(nicotinate and nicotinamide metabolism,fatty acid metabolism).Conclusions:COPs supplementation has displayed the potentials on alleviating the injury of liver function and it may be due to regulation of fatty acid metabolism,nicotinate and nicotinamide metabolism,lipid peroxidation and anti-inflammatory action.More researches are warranted in future to confirm the exact mechanisms.展开更多
Solid lipid nanoparticles(SLN)could enhance the oral bioavailability of loaded protein and peptide drugs through lymphatic transport.Natural oligopeptides regulate nearly all vital processes and serve as a nitrogen so...Solid lipid nanoparticles(SLN)could enhance the oral bioavailability of loaded protein and peptide drugs through lymphatic transport.Natural oligopeptides regulate nearly all vital processes and serve as a nitrogen source for nourishment.They are mainly transported by oligopeptide transporter-1(PepT-1)which are primarily expressed in the intestine with the characteristics of high-capacity and low energy consumption.Our preliminary research discovered the transmembrane transport of SLN could be improved by stimulating the oligopeptide absorption pathway.This implied the potential of combining the advantages of SLN with oligopeptide transporter mediated transportation.Herein,two kinds of dipeptide modified SLN were designed with insulin and glucagon like peptide-1(GLP-1)analogue exenatide as model drugs.These drugs loaded SLN showed enhanced oral bioavailability and hypoglycemic effect in both type I diabetic C57BL/6mice and type II diabetic KKAymice.Compared with un-modified SLN,dipeptide-modified SLN could be internalized by intestinal epithelial cells via PepT-1-mediated endocytosis with higher uptake.Interestingly,after internalization,more SLN could access the systemic circulation via lymphatic transport pathway,highlighting the potential to combine the oligopeptide-absorption route with SLN for oral drug delivery.展开更多
High Fischer ratio oligopeptides(HFOPs)have a variety of physiological activities,but there are few literatures reporting the hepatoprotective effects of HFOPs against acetaminophen(APAP)-induced liver injury.The ob-j...High Fischer ratio oligopeptides(HFOPs)have a variety of physiological activities,but there are few literatures reporting the hepatoprotective effects of HFOPs against acetaminophen(APAP)-induced liver injury.The ob-jectives of this study were to establish the preparation process of HFOPs from hard-shelled mussel(Mytilus coruscus)(HFOPs-HM)and investigate the hepatoprotective effects and potential mechanisms of HFOPs-HM against APAP-induced liver injury in mice.Therefore,trypsin and papain were selected as the endo and exog-enous proteases for preparing HFOPs-HM according to the degree of hydrolysis(DH)of hard-shelled mussel hydrolysates,and activated carbon of XHJ-200 displayed the best effect to remove aromatic amino acids ac-cording to the Fischer ratio(OD220/OD280)and its parameters were optimized as adsorption time of 3.0 h and solid-liquid ratio of 1:10.The HFOPs-HM’s Fischer ratio and average molecular weight were 26.03(>20)and 878.54 Da,respectively.Furthermore,a mice model of liver injury induced by APAP was established.HFOPs-HM could significantly improve liver index and histopathological features,decrease the serum alanine aminotrans-ferase(ALT)and aspartate transaminase(AST)activities,increase the glutathione content and superoxide dis-mutase(SOD)and catalase(CAT)activities.Further research demonstrated that HFOPs-HM could alleviate liver oxidative stress in liver tissue via activating the Nrf2 pathway to initiate the intracellular antioxidant enzyme system.In addition,HFOPs-HM also suppressed liver inflammation by downregulating the secretion of TNF-α,IL-1β,and IL-6.Thus,HFOPs-HM could serve as an auxiliary functional dietary molecule applied in function products to alleviate drug-induced liver injury.展开更多
Fructose consumption has risen dramatically in recent decades due to the use of sucrose and high fructose corn syrup in beverages and processed foods,contributing to rising rates of hyperuricemia.The purpose of this e...Fructose consumption has risen dramatically in recent decades due to the use of sucrose and high fructose corn syrup in beverages and processed foods,contributing to rising rates of hyperuricemia.The purpose of this experiment was to explore the anti-hyperuricemia effects of an active oligopeptide(GPSGRP)derived from sea cucumber in fructose induced hyperuricemia mouse model,and to clarify the underlying mechanism in sight of gut microbiota and serum metabolites.Peptide GPSGRP treatment rebalanced uric acid metabolism and alleviated inflammatory response in mice.In addition,treatment with GPSGRP decreased the abundance of Bacteroides and Proteobacteria at the phylum level,Muribaculum,Prevotella and Bacteroides at the genus level,and inhibited the related pathways of purine metabolism and glycolysis/gluconeogenesis metabolism.Moreover,serum metabolites,including linoleic acid,indole and its derivatives,arachidonic acid and uridine,as well as related metabolic pathways,such as tricarboxylic acid cycle,ketone production and sugar production,were altered in response to GPSGRP treatment.This study provides a valuable reference for the application and development of marine biological peptides in uric acid management.展开更多
Fluoroalkyl derivatives of two biologically active oligopeptides [(m-CF3)Tyr(1)]-Leu-enkephalin, [(m-C2F4Cl)Tyr(1)]-Leu-enkephalin and [(m-COCF2Cl)Tyr(2)]-melanocyte-stimulating hormone releasing hormone have been syn...Fluoroalkyl derivatives of two biologically active oligopeptides [(m-CF3)Tyr(1)]-Leu-enkephalin, [(m-C2F4Cl)Tyr(1)]-Leu-enkephalin and [(m-COCF2Cl)Tyr(2)]-melanocyte-stimulating hormone releasing hormone have been synthesized. Studies on the activities of these peptides are underway.展开更多
Reversible protein phosphorylation is of great importance in the regulation of many cellular processes. Structurally well defined compounds are needed for the study of the roles of the phospho proteins in biologica...Reversible protein phosphorylation is of great importance in the regulation of many cellular processes. Structurally well defined compounds are needed for the study of the roles of the phospho proteins in biological processes. In this paper, O phosphorylated oligopeptides were synthesized using bis alkyloxy N,N dialkylphosphoramidite reacting with the oligopeptide followed by oxidation. Many hydroxyl groups in oligopeptides can be phosphorylated in one step.展开更多
We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-aminoamides.This protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challengin...We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-aminoamides.This protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product conjugates.Site selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal chemistry.Mechanism investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.展开更多
Thrombosis and inflammation are primary contributors to the onset and progression of ischemic stroke.The contact-kinin pathway,initiated by plasma kallikrein(PK)and activated factor XII(FXIIa),functions bidirectionall...Thrombosis and inflammation are primary contributors to the onset and progression of ischemic stroke.The contact-kinin pathway,initiated by plasma kallikrein(PK)and activated factor XII(FXIIa),functions bidirectionally with the coagulation and inflammation cascades,providing a novel target for therapeutic drug development in ischemic stroke.In this study,we identified a bat-derived oligopeptide from Myotis myotis(Borkhausen,1797),designated LE6(Leu-Ser-Glu-Glu-Pro-Glu,702 Da),with considerable potential in stroke therapy due to its effects on the contact kinin pathway.Notably,LE6 demonstrated significant inhibitory effects on PK and FXIIa,with inhibition constants of 43.97μmol/L and 6.37μmol/L,respectively.In vitro analyses revealed that LE6 prolonged plasma recalcification time and activated partial thromboplastin time.In murine models,LE6 effectively inhibited carrageenan-induced mouse tail thrombosis,FeCl3-induced carotid artery thrombosis,and photochemically induced intracerebral thrombosis.Furthermore,LE6 significantly decreased inflammation and stroke injury in transient middle cerebral artery occlusion models.Notably,the low toxicity,hemolytic activity,and bleeding risk of LE6,along with its synthetic simplicity,underscore its clinical applicability.In conclusion,as an inhibitor of FXIIa and PK,LE6 offers potential therapeutic benefits in stroke treatment by mitigating inflammation and preventing thrombus formation.展开更多
The fundamental optical storage mechanism of the laser light eddressable azobenzene moiety is briefly introduced.A modular and flexible synthesis design furnishes polyester matrices covalently integrating cyanoazobenz...The fundamental optical storage mechanism of the laser light eddressable azobenzene moiety is briefly introduced.A modular and flexible synthesis design furnishes polyester matrices covalently integrating cyanoazobenzene in regularlyspaced side chains. Thin films of these materials are particularly well suited for holographic storape. Notable figures of meritsof liquid crystalline polyesters are response time to blue-green laser light of the order of nanoseconds, storage capacityexpressed as 5000 lines/mm, and high, permanent (almost nine years) diffraction efficiency of the order of 50% or greater,and erasability, The implications of the main chain nature for polyester morphology and for the permanency of the inducedanisotropy are discussed, The design and methods of preparation of other significantly different polymer scaffolds supportingcyanoazobenzene are elaborated. Oligopeptides always result in amorphous materials, whereas copolymethacrylates anddendritic or hyperbranched polyesters provide some materials that exhibit liquid crystallinity. However, none of these scaffolds affords materials that result in permanent anisotropy when exposed to interfering laser light.展开更多
An oral drug delivery system using proteinoid microspheres is discussed with respect to itsunique dependence on pH. It has been found that certain drugs such as insulin and heparin canbe encapsulated in proteinoid sph...An oral drug delivery system using proteinoid microspheres is discussed with respect to itsunique dependence on pH. It has been found that certain drugs such as insulin and heparin canbe encapsulated in proteinoid spheres at stomach pH's (1--3). These spheres also dissemble atintestinal pH's (6--7) releasing the drug for absorption. Using this technique low molecularweight heparin and human growth hormone have been orally delivered successfully to severalanimal species. Future work has been proposed to study the interaction and binding of thespecific drugs with synthesized oligopeptides.展开更多
Dry-curing,wet-curing,stewing and marinating are sequential Chinese traditional meat-processing methods dating back thousands of years ago.However,little information is available about the contribution of each process...Dry-curing,wet-curing,stewing and marinating are sequential Chinese traditional meat-processing methods dating back thousands of years ago.However,little information is available about the contribution of each processing stage to the umami taste in duck breast meat.Therefore,effects of those meat-processing methods on umami taste related chemical compounds were determined in this study.Dry-curing significantly increased free amino acids,oligopeptides and nucleotides and nucleotides degradation products(P<0.05),however,in the following wet-curing,stewing and marinating stages,the percentages of inosine and hypoxanthine were gradually declined.Electronic tongue and principle component analysis results revealed the difference between dry-cured/wet-cured duck breast meat and marinated/stewed duck breast meat was due to the increase of free amino acids,oligopeptides and inosine monophosphate.Therefore,dry-curing is an important stage in meat processing,not only it produces a pool of taste related compounds,it also stimulates the enzyme activities in the muscle.Meanwhile,in the stewing stage,the umami taste profile of duck breast meat was gradually established.We can conclude that dry-curing and stewing are the two crucial stages to form the umami taste profile in duck breast meat.展开更多
For decades,the preparation of polyisoprene rubber that can match the comprehensive properties of natural rubber(NR)has been pursued.While sacrificial bonds have been used to promote the strength and toughness of rubb...For decades,the preparation of polyisoprene rubber that can match the comprehensive properties of natural rubber(NR)has been pursued.While sacrificial bonds have been used to promote the strength and toughness of rubbers,little is known about their effects on fatigue resistance,which is important in dynamic environments.Herein,terminal block and randomly functionalized polyisoprene rubbers tethered with di-alanine,tri-alanine and tetra-alanine were prepared.The results showed that the flow activation energy,aggregates ordering and energy dissipation of the hydrogen-bonded aggregates increase with the elongation of oligopeptide length(XA,X=2,3,4),therefore resulting in enhanced mechanical strength and toughness of corresponding samples.Comparably,the tear strengths are barely affected by oligopeptide lengths in block samples,but promoted from dipeptide to tetrapeptide in random samples,probably due to the well dispersed oligopeptide aggregates.Most importantly,it is found that the tight binding aggregates of oligopeptides are critical for the excellent fatigue resistance,which is absent in polyisoprene and natural rubber.The loose aggregates dissociate and recombine repeatedly under cyclic loading and the tight aggregates keep the network integrated and robust.Interestingly,the largest hysteresis of PIP-4A-V with the longest oligopeptide length give the lowest heat generation,which is contrary to the traditional sacrificial bonds.Overall,the oligopeptide aggregates have repeatable energy dissipation properties and cycle life comparable to or even surpassing those of the linked proteins in NR,resulting in similar tensile strength,fracture toughness,and better fatigue resistance relative to NR.This deep insight on the role of oligopeptide aggregates is very useful for the engineering rubbers served in dynamic environments.展开更多
基金This work was supported by the National Science Foundation.
文摘Two new oligopeptides, Asterin A and B, have been isolated from the roots of Aster tataricus L. f., and their structures were elucidated on the basis of spectroscop- ic, chemical and enzymatic methods.
文摘A highly sensitive HPLC method for the detection of amino acids and oligopeptides with 9-acridine formyl chloride by pre-column fluorescence derivatization has been developed. Glycine, glycylglycine, histidine, triglycine and glutathione were separated on a reversed-phase C-18 column with methanol-water-triethylamine eluent, derivatization and chromatographic conditions were optimized. The five derivatives were eluted in 28 min with a good reproducibility. Linear range of the calibration graph was 0.08-260 nmol/ml(-1). The relative standard deviations(n=6) are < 5%. Detection limits (signal-to-noise ratio=3) for the five derivatives are 20-40 fmol.
基金the National Natural Science Foundation of China(No.30770228)for financial support
文摘A series of novel gossypol derivatives were synthesized and screened for their in vitro anti-HIV- 1I activity. The results showed that replacing the aldehyde groups of gossypol with certain oligopeptides and Dglucosamine not only reduced the cytotoxicity of gossypol derivatives but also enhanced their antiviral activity against HIV-1. Interestingly, D-glucosamine derivative of gossypol that lacked the COONa group also exhibited the same potent anti-HIV-1 activity as oligopeptide derivatives with the COONa group. These compounds blocked the entry of HIV-1ⅢB into target cell. which was similar to T20. Furthermore, the molecular docking analysis rationalized their anti-HIV-1 activity. The results also implied that certain oligopeptides and D-glucosamine were important moities to prepare gossypol derivatives as HIV- 1 entry inhibitors besides certain amino acids.
文摘We previously investigated the physiological effect of an ethanol extract of fermented soymilk on rats and clarified that this extract modulated their hepatic lipid metabolism. Although the soy isoflavones and oligopeptides are representative functional components of the ethanol extract, it remained unclear whether these substances share a role in lipid metabolism modulation. Therefore, we attempted to clarify the effects of isoflavones and oligopeptides in lactic acid-fermented soymilk on lipid metabolism-related gene expression in rats and HepG2 cells. The fermented soymilk extract had a higher isoflavone aglycone content than the soymilk extract. Sevenweek-old male Sprague-Dawley rats were fed an AIN-93G diet, a diet plus 70% soymilk ethanol extract, or a diet plus 70% fermented soymilk ethanol extract for 5 weeks. Although both the soymilk and fermented soymilk ethanol extracts did not significantly affect plasma and hepatic lipid profiles, the expression levels of the genes encoding CYP7a1 and SREBP-2 were significantly upregulated in the livers of rats fed with the fermented soymilk extract. Whereas isoflavone aglycones upregulated CYP7a1-encoding gene expression in HepG2, oligopeptides in soymilk and fermented soymilk downregulated this expression. Oligopeptides in fermented soymilk downregulated the expression stronger than that observed with soymilk. On the other hand, no significant change in FAS expression was observed in the livers of rats fed the fermented soymilk extract. Although isoflavone aglycones did not affect FAS expression in HepG2 cells, oligopeptides in fermented soymilk downregulated FAS expression. The downregulation of FAS with oligopeptides from fermented soymilk was stronger than that from soymilk. In the present animal experiment, the effect on reduction of fat synthesis was not found because of insufficient amount of peptides derived from digestion of soy protein. These results suggest that isoflavone aglycones increase CYP7a1 gene expression, whereas oligopeptides decrease FAS expression. Isoflavone glycosides and proteins in soymilk were converted to isoflavone aglycones and oligopeptides by lactic acid fermentation, respectively, and these functional components independently improved the lipid metabolism. In the present study, it was found that isoflavone aglycones and oligopeptides in fermented soymilk differentially regulate hepatic lipid metabolism-related gene expression. Therefore, the consumption of fermented soymilk containing isoflavone aglycones and soy oligopeptides might prevent dyslipidemia more effectively than that of any other soy food. Fermented soymilk is a superior functional food modulating lipid metabolism.
基金supported by the National Nature Science Foundation of China(Nos.51861145311,22005338)Science Foundation of China University of Petroleum,Beijing(No.2462017YJRC027)Open Project of State Key Laboratory of Superhard Materials(Jilin University 201802)。
文摘For bone regenerative engineering,it is a promising method to form skeletal tissues differentiating from human bone morrow mesenchyme stem cells(hBMSCs).However,it is still a critical challenge to efficiently control ostogenesis and clearly reveal the influence factor.To this end,the fluorescent gold nanodots(Au NDs) with highly negative charges as osteogenic induction reagent are successfully synthesized,which display better than commercial osteogenic induction medium through the investigations of ALP activity(2.5 folds) and cytoskeleton staining(1.5 folds).Two kinds of oligopeptides with different bio-structures(cysteine,Cys and glutathione,GSH) are selected for providing surficial charges on Au NDs.It is revealed that Au-Cys with more negative charges(-51 mV) play better role than Au-GSH(-19 mV) in osteogenic differentiation,when both of them have same size(~2 nm),sphere shape and show similar cell uptake amount.To explore deeply,osteogenesis related signaling pathways are monitored,revealing that the enhancement of osteogenic differentiation was through autophagy signaling pathway triggered by Au-Cys.And the promotion of highly negative charges in osteogenic diffe rentiation was further proved via sliver nanodots(Ag NDs,Ag-Cys and Ag-GSH) and carbon nanodots(CDs,Cys-CDs and GSH-CDs).This work indicates part of insights during hBMSCs differentiation and provides a novel strategy in osteogenic differentiation process.
基金The research was funded by the 2020 Shenzhen International Scientific and Technological Cooperation R&D Project(No.GJHZ20190823111601682)the Natural Science Foundation of Guangdong Province(No.2020A 1515011075)+2 种基金It was supported by the Special Funds for the‘Cultivation of Guangdong College Students’Scientific and Technological Innovation(‘Climbing Program’Special Funds No.pdjh2022a0232)The study also was funded by the Postgraduate Education Innovation Project of Guangdong Ocean University(No.2021148)Innovative Training Program for College Students of Guangdong Ocean University(No.S202210566067)。
文摘DAPTMGY(DTY)is an oligopeptide derived from marine microalgae with proven potential to combat oxidative stress in previous research.The composition,ordering,and active sites of amino acids play a key role in activity studies and are also the research trends in recent years.As an oligopeptide with a molecular weight of less than 1000 Da,DTY is of great significance to explore the active site and structure-activity relationship.This study used quantum mechanics to optimize DTY’s structure and predict the active site through molecular orbits,energy,and charge.In addition,an LPS-treated HUVEC cell was established as an oxidative-stress model.DTY could reduce mitochondrial oxidative stress and inhibit ROS production by enhancing the antioxidant enzymes SOD,GPX,and HO-1.Moreover,it was confirmed to inhibit inflammation and apoptosis through the NF-κB and MAPK signaling pathways.Lastly,the correlation of the oligopeptide DTY’s active site and antioxidative-stress activity was verified by molecular docking,showing that hydrogen bonding is the main force,which was also the main factor for antioxidant activity.
基金the Zhongyuan Scholars in Henan Province(192101510004)Major Science and Technology Projects for Public Welfare of Henan Province(201300110300)+2 种基金Key Technology ResearchDevelopment and Demonstration Applications for Integrated Development of the Whole Wheat Industry Chain(221100110700)Central Government Guides Local Funds for Science and Technology Development(Z20221341069).
文摘High Fischer ratio oligopeptides(HFROs)are a group of oligopeptides containing high levels of branched-chain amino acids(BCAA)and low levels of aromatic amino acids(AAA).HFROs have received a lot of attention as they are believed to have significant physiological activities,including antioxidant,liver damage repair,anti-fatigue,anti-tumor and energy supply to the body.HFROs are available from a wide range of sources and both plant and animal proteins can be used to prepare HFROs but the physiological tolerability and rejection of special populations needs to be considered.Enzymatic hydrolysis is the most common method for the preparation of HFROs,but optimization of the separation and purification process is still needed in the future.Diseases caused by disruptions in the balance of BCAA and AAA in the blood,such as hepatic encephalopathy,can be treated by supplementing HFROs with drugs or food.In addition,HFROs are able to reduce fatigue feedback and assist in the treatment of phenylketonuria at the molecular nutrient level.The aim of this review is to review recent research on HFROs and provide new perspectives on the high value use of crops and the development of novel functional and special medical purpose foods.
基金We sincerely thank all support from National Key Research and Development Program of China(No.2016YFD0400604).
文摘Background:Liver cancer as the main leading cancer has caused heavy burdens globally.The prognosis of liver cancer is closely related with postoperative nutrition support.Corn oligopeptides(COPs)are protein hydrolysates produced by enzymatic treatments,which have shown potential bioactivities,such as inhibiting angiotensin I-converting enzyme,resisting lipid peroxidation and anti-oxidant.However,the correlation between COPs and liver cancer patients is still unknown and the potential mechanism of COPs on liver cancer is unclear as well.The aim of this study was to assess effects of 7-day intervention of COPs after surgery on liver function and serum metabolic profiles of liver cancer patients.Methods:Patients were assigned into COPs intervention group(n=50)and control group(n=91)for 7 days.Investigations were scheduled at 1st day and 7th day after liver resection surgery respectively,mainly including anthropometric,biochemical indexes and liquid chromatography-mass spectrometry(LC/MS)analysis.Results:Seven-day supplementation of COPs on early post-surgery liver cancer patients down-regulated levels of alanine aminotransferase,aspartate aminotransferase,total bilirubin,direct bilirubin and up-regulated prothrombin time activity and prealbumin levels.LC/MS analysis revealed metabolic signatures including regulation of 16 metabolites,which was closely related with two metabolic pathways(nicotinate and nicotinamide metabolism,fatty acid metabolism).Conclusions:COPs supplementation has displayed the potentials on alleviating the injury of liver function and it may be due to regulation of fatty acid metabolism,nicotinate and nicotinamide metabolism,lipid peroxidation and anti-inflammatory action.More researches are warranted in future to confirm the exact mechanisms.
基金supported by National Key Research and Development Program of China(Grant No.2021YFE0115200)the Regional Innovation and Development Joint Fund of National Natural Science Foundation of China(Grant No.U22A20356).
文摘Solid lipid nanoparticles(SLN)could enhance the oral bioavailability of loaded protein and peptide drugs through lymphatic transport.Natural oligopeptides regulate nearly all vital processes and serve as a nitrogen source for nourishment.They are mainly transported by oligopeptide transporter-1(PepT-1)which are primarily expressed in the intestine with the characteristics of high-capacity and low energy consumption.Our preliminary research discovered the transmembrane transport of SLN could be improved by stimulating the oligopeptide absorption pathway.This implied the potential of combining the advantages of SLN with oligopeptide transporter mediated transportation.Herein,two kinds of dipeptide modified SLN were designed with insulin and glucagon like peptide-1(GLP-1)analogue exenatide as model drugs.These drugs loaded SLN showed enhanced oral bioavailability and hypoglycemic effect in both type I diabetic C57BL/6mice and type II diabetic KKAymice.Compared with un-modified SLN,dipeptide-modified SLN could be internalized by intestinal epithelial cells via PepT-1-mediated endocytosis with higher uptake.Interestingly,after internalization,more SLN could access the systemic circulation via lymphatic transport pathway,highlighting the potential to combine the oligopeptide-absorption route with SLN for oral drug delivery.
基金funded by the National Natural Science Foundation of China,China(No.82073764)the Ten-thousand Talents Plan of Zhe-jiang Province,China(No.2019R52026).
文摘High Fischer ratio oligopeptides(HFOPs)have a variety of physiological activities,but there are few literatures reporting the hepatoprotective effects of HFOPs against acetaminophen(APAP)-induced liver injury.The ob-jectives of this study were to establish the preparation process of HFOPs from hard-shelled mussel(Mytilus coruscus)(HFOPs-HM)and investigate the hepatoprotective effects and potential mechanisms of HFOPs-HM against APAP-induced liver injury in mice.Therefore,trypsin and papain were selected as the endo and exog-enous proteases for preparing HFOPs-HM according to the degree of hydrolysis(DH)of hard-shelled mussel hydrolysates,and activated carbon of XHJ-200 displayed the best effect to remove aromatic amino acids ac-cording to the Fischer ratio(OD220/OD280)and its parameters were optimized as adsorption time of 3.0 h and solid-liquid ratio of 1:10.The HFOPs-HM’s Fischer ratio and average molecular weight were 26.03(>20)and 878.54 Da,respectively.Furthermore,a mice model of liver injury induced by APAP was established.HFOPs-HM could significantly improve liver index and histopathological features,decrease the serum alanine aminotrans-ferase(ALT)and aspartate transaminase(AST)activities,increase the glutathione content and superoxide dis-mutase(SOD)and catalase(CAT)activities.Further research demonstrated that HFOPs-HM could alleviate liver oxidative stress in liver tissue via activating the Nrf2 pathway to initiate the intracellular antioxidant enzyme system.In addition,HFOPs-HM also suppressed liver inflammation by downregulating the secretion of TNF-α,IL-1β,and IL-6.Thus,HFOPs-HM could serve as an auxiliary functional dietary molecule applied in function products to alleviate drug-induced liver injury.
基金sponsored by the One Health Interdisciplinary Research Project,Ningbo University,Open Fund of Key Laboratory of Aquacultural Biotechnology Ministry of Education in Ningbo University,and K.C.Wong Magna Fund of Ningbo Universitythe National Natural Science Foundation China(32270115)+1 种基金National Key R&D Program of China(2018YFD0901102)Fundamental Research Funds for the Provincial Universities of Zhejiang(SJLY2021015)。
文摘Fructose consumption has risen dramatically in recent decades due to the use of sucrose and high fructose corn syrup in beverages and processed foods,contributing to rising rates of hyperuricemia.The purpose of this experiment was to explore the anti-hyperuricemia effects of an active oligopeptide(GPSGRP)derived from sea cucumber in fructose induced hyperuricemia mouse model,and to clarify the underlying mechanism in sight of gut microbiota and serum metabolites.Peptide GPSGRP treatment rebalanced uric acid metabolism and alleviated inflammatory response in mice.In addition,treatment with GPSGRP decreased the abundance of Bacteroides and Proteobacteria at the phylum level,Muribaculum,Prevotella and Bacteroides at the genus level,and inhibited the related pathways of purine metabolism and glycolysis/gluconeogenesis metabolism.Moreover,serum metabolites,including linoleic acid,indole and its derivatives,arachidonic acid and uridine,as well as related metabolic pathways,such as tricarboxylic acid cycle,ketone production and sugar production,were altered in response to GPSGRP treatment.This study provides a valuable reference for the application and development of marine biological peptides in uric acid management.
基金Project supported by the National Natural Science Foundation of China.
文摘Fluoroalkyl derivatives of two biologically active oligopeptides [(m-CF3)Tyr(1)]-Leu-enkephalin, [(m-C2F4Cl)Tyr(1)]-Leu-enkephalin and [(m-COCF2Cl)Tyr(2)]-melanocyte-stimulating hormone releasing hormone have been synthesized. Studies on the activities of these peptides are underway.
文摘Reversible protein phosphorylation is of great importance in the regulation of many cellular processes. Structurally well defined compounds are needed for the study of the roles of the phospho proteins in biological processes. In this paper, O phosphorylated oligopeptides were synthesized using bis alkyloxy N,N dialkylphosphoramidite reacting with the oligopeptide followed by oxidation. Many hydroxyl groups in oligopeptides can be phosphorylated in one step.
基金support from the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province(No.UNPYSCT-2017124)。
文摘We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-aminoamides.This protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product conjugates.Site selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal chemistry.Mechanism investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.
基金supported by the National Natural Science Foundation of China(32200397,23SWAQ09,and 31930015)Yunnan Province Grant(202302AA310032,202302AA310035,and 202003AD150008)+5 种基金Ministry of Science and Technology of China(2018YFA0801403)Chinese Academy of Sciences(SAJC202103 and KFJ-BRP-008-003)New Cornerstone Investigator Program(NCI202238)Kunming Science and Technology Bureau(2022SCP007)Priority Union Foundation of Yunnan Provincial Science and Technology Department and Kunming Medical University(202101AC070461)Basic Research Program of Yunnan Province Science and Technology Department(202301AT070083)。
文摘Thrombosis and inflammation are primary contributors to the onset and progression of ischemic stroke.The contact-kinin pathway,initiated by plasma kallikrein(PK)and activated factor XII(FXIIa),functions bidirectionally with the coagulation and inflammation cascades,providing a novel target for therapeutic drug development in ischemic stroke.In this study,we identified a bat-derived oligopeptide from Myotis myotis(Borkhausen,1797),designated LE6(Leu-Ser-Glu-Glu-Pro-Glu,702 Da),with considerable potential in stroke therapy due to its effects on the contact kinin pathway.Notably,LE6 demonstrated significant inhibitory effects on PK and FXIIa,with inhibition constants of 43.97μmol/L and 6.37μmol/L,respectively.In vitro analyses revealed that LE6 prolonged plasma recalcification time and activated partial thromboplastin time.In murine models,LE6 effectively inhibited carrageenan-induced mouse tail thrombosis,FeCl3-induced carotid artery thrombosis,and photochemically induced intracerebral thrombosis.Furthermore,LE6 significantly decreased inflammation and stroke injury in transient middle cerebral artery occlusion models.Notably,the low toxicity,hemolytic activity,and bleeding risk of LE6,along with its synthetic simplicity,underscore its clinical applicability.In conclusion,as an inhibitor of FXIIa and PK,LE6 offers potential therapeutic benefits in stroke treatment by mitigating inflammation and preventing thrombus formation.
文摘The fundamental optical storage mechanism of the laser light eddressable azobenzene moiety is briefly introduced.A modular and flexible synthesis design furnishes polyester matrices covalently integrating cyanoazobenzene in regularlyspaced side chains. Thin films of these materials are particularly well suited for holographic storape. Notable figures of meritsof liquid crystalline polyesters are response time to blue-green laser light of the order of nanoseconds, storage capacityexpressed as 5000 lines/mm, and high, permanent (almost nine years) diffraction efficiency of the order of 50% or greater,and erasability, The implications of the main chain nature for polyester morphology and for the permanency of the inducedanisotropy are discussed, The design and methods of preparation of other significantly different polymer scaffolds supportingcyanoazobenzene are elaborated. Oligopeptides always result in amorphous materials, whereas copolymethacrylates anddendritic or hyperbranched polyesters provide some materials that exhibit liquid crystallinity. However, none of these scaffolds affords materials that result in permanent anisotropy when exposed to interfering laser light.
文摘An oral drug delivery system using proteinoid microspheres is discussed with respect to itsunique dependence on pH. It has been found that certain drugs such as insulin and heparin canbe encapsulated in proteinoid spheres at stomach pH's (1--3). These spheres also dissemble atintestinal pH's (6--7) releasing the drug for absorption. Using this technique low molecularweight heparin and human growth hormone have been orally delivered successfully to severalanimal species. Future work has been proposed to study the interaction and binding of thespecific drugs with synthesized oligopeptides.
文摘Dry-curing,wet-curing,stewing and marinating are sequential Chinese traditional meat-processing methods dating back thousands of years ago.However,little information is available about the contribution of each processing stage to the umami taste in duck breast meat.Therefore,effects of those meat-processing methods on umami taste related chemical compounds were determined in this study.Dry-curing significantly increased free amino acids,oligopeptides and nucleotides and nucleotides degradation products(P<0.05),however,in the following wet-curing,stewing and marinating stages,the percentages of inosine and hypoxanthine were gradually declined.Electronic tongue and principle component analysis results revealed the difference between dry-cured/wet-cured duck breast meat and marinated/stewed duck breast meat was due to the increase of free amino acids,oligopeptides and inosine monophosphate.Therefore,dry-curing is an important stage in meat processing,not only it produces a pool of taste related compounds,it also stimulates the enzyme activities in the muscle.Meanwhile,in the stewing stage,the umami taste profile of duck breast meat was gradually established.We can conclude that dry-curing and stewing are the two crucial stages to form the umami taste profile in duck breast meat.
基金financially supported by the National Natural Science Foundation of China(No.51973126)the State Key Laboratory of Polymer Materials Engineering(No.sklpme20222-11)。
文摘For decades,the preparation of polyisoprene rubber that can match the comprehensive properties of natural rubber(NR)has been pursued.While sacrificial bonds have been used to promote the strength and toughness of rubbers,little is known about their effects on fatigue resistance,which is important in dynamic environments.Herein,terminal block and randomly functionalized polyisoprene rubbers tethered with di-alanine,tri-alanine and tetra-alanine were prepared.The results showed that the flow activation energy,aggregates ordering and energy dissipation of the hydrogen-bonded aggregates increase with the elongation of oligopeptide length(XA,X=2,3,4),therefore resulting in enhanced mechanical strength and toughness of corresponding samples.Comparably,the tear strengths are barely affected by oligopeptide lengths in block samples,but promoted from dipeptide to tetrapeptide in random samples,probably due to the well dispersed oligopeptide aggregates.Most importantly,it is found that the tight binding aggregates of oligopeptides are critical for the excellent fatigue resistance,which is absent in polyisoprene and natural rubber.The loose aggregates dissociate and recombine repeatedly under cyclic loading and the tight aggregates keep the network integrated and robust.Interestingly,the largest hysteresis of PIP-4A-V with the longest oligopeptide length give the lowest heat generation,which is contrary to the traditional sacrificial bonds.Overall,the oligopeptide aggregates have repeatable energy dissipation properties and cycle life comparable to or even surpassing those of the linked proteins in NR,resulting in similar tensile strength,fracture toughness,and better fatigue resistance relative to NR.This deep insight on the role of oligopeptide aggregates is very useful for the engineering rubbers served in dynamic environments.
