The spike protein(S)of SARS-CoV-2 is responsible for viral attachment and entry,thus a major factor for host suscep-tibility,tissue tropism,virulence and pathogenicity.The S is divided with S1 and S2 region,and the S1...The spike protein(S)of SARS-CoV-2 is responsible for viral attachment and entry,thus a major factor for host suscep-tibility,tissue tropism,virulence and pathogenicity.The S is divided with S1 and S2 region,and the S1 contains the receptor-binding domain(RBD),while the S2 contains the hydrophobic fusion domain for the entry into the host cell.Numerous host proteases have been implicated in the activation of SARS-CoV-2 S through various c leavage sites.In this article,we review host proteases including furin,trypsin,transmembrane protease serine 2(TMPRSS2)and cathepsins in the activation of SARS-CoV-2 S.Many betacoronaviruses including SARS-CoV-2 have polybasic residues at the S1/S2 site which is subjected to the cleavage by furin.The S1/S2 cleavage facilitates more assessable RBD to the receptor ACE2,and the binding triggers further conformational changes and exposure of the S2'site to proteases such as type Il transmembrane serine proteases(TTPRs)including TMPRSS2.In the presence of TMPRSS2 on the target cells,SARS-CoV-2 can utilize a direct entry route by fusion of the viral envelope to the cellular membrane.In the absence of TMPRSS2,SARS-CoV-2 enter target cells via endosomes where multiple cathepsins cleave the S for the successful entry.Additional host proteases involved in the cleavage of the S were discussed.This article also includes roles of 3C-like protease inhibitors which have inhibitory activity against cathepsin L in the entry of SARS-CoV-2,and discussed the dual roles of such inhibitors in virus replication.展开更多
Toll-like receptor 4(TLR4) and protease-activated receptor 2(PAR2) play pivotal roles in the mammalian innate immune response.Notably,in addition to their involvement in detection of invading pathogens,PAR2 and TLR4 m...Toll-like receptor 4(TLR4) and protease-activated receptor 2(PAR2) play pivotal roles in the mammalian innate immune response.Notably,in addition to their involvement in detection of invading pathogens,PAR2 and TLR4 modulate the levels of cell death-induced sterile inflammation by activating pro-or anti-inflammatory downstream signaling cascades.Within the central nervous system,there is emerging evidence that both receptors are involved in synaptic transmission and brain plasticity.Furthermore,due to their prominent role in mediating neuroinflammation,PAR2 and TLR4 are associated with development and progression of neurodegenerative disorders including but not limited to Alzheimer's disease,Parkinson's disease and multiple sclerosis.In this article,we summarise the current knowledge on the cooperation between PAR2 and TLR4,discuss the potential cross-talk levels and highlight the impact of the cross-coupling on neuroinflammation.展开更多
Objective Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the causative agent for coronavirus disease 2019(COVID-19),is responsible for the recent global pandemic.As there are no effective drugs or vaccine...Objective Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the causative agent for coronavirus disease 2019(COVID-19),is responsible for the recent global pandemic.As there are no effective drugs or vaccines available for SARS-CoV-2,we investigated the potential of flavonoids against SARS-CoV-2 main protease 6YNQ.Methods In silico molecular simulation study against SARS-CoV-2 main protease 6YNQ.Results Among the 21 selected flavonoids,rutin demonstrated the highest binding energy(−8.7 kcal/mol)and displayed perfect binding with the catalytic sites.Conclusions Our study demonstrates the inhibitory potential of flavonoids against SARS-CoV-2 main protease 6YNQ.These computational simulation studies support the hypothesis that flavonoids might be helpful for the treatment of COVID-19.展开更多
Summary： The role of protease activated receptor-2 （PAR-2） in the renal tubulointerstitial lesion induced by unilateral ureteral obstruction （UUO） was explored. Mice were sacrificed on the day 1, 3, 5, 7, 10, 14 ...Summary： The role of protease activated receptor-2 （PAR-2） in the renal tubulointerstitial lesion induced by unilateral ureteral obstruction （UUO） was explored. Mice were sacrificed on the day 1, 3, 5, 7, 10, 14 and 21 after UUO. The expression of PAR-2 mRNA and protein and a-smooth muscle actin （α-SMA） protein in tubuloin,terstitium was detected by RT-PCR and immunohistochemistry at each time point, respedtively. The results showed that the PAR-2 expression in renal tubulointerstitium was increased progressively starting from 24 h to the day 14 post-ligation, and it was significantly associated with the relative volume of interstitium and the positive area of α-SMA. PAR-2 was mainly expressed in renal tubule epithelial cells, especially in proximal tubular cells. It also located in renal capillary ansa, interstitial infiltrate cells and fibroblasts. It was concluded that PAR-2 was active in interstitial and tubular cells in the early phase of fibrotic process and played an important role in mediating the tubulointerstitial lesion after UUO.展开更多
Objective： To investigated whether epigenetic mechanisms contribute to the variable expression of variable protease nexin1（PN-1） encoded by the SERPINE2 gene in different cell types. Methods： Working with 5 human ...Objective： To investigated whether epigenetic mechanisms contribute to the variable expression of variable protease nexin1（PN-1） encoded by the SERPINE2 gene in different cell types. Methods： Working with 5 human cell lines, we determined the CpG methylation status within two CpG islands in the SERPINE2 gene by bisulphate sequencing and the PN-1 mRNA level by Q-RT PCR. Results： A CpG island spanning the transcription initiation site showed little methylation in 3 of the cell lines and substantial methylation in 2 of the cell lines. A CpG island covering the translation starting site showed full methylation in all investigated cell lines. Methylation within the CpG island was not randomly distributed, but showed accumulation at specific sites. However, we were not able to distinguish any patterns which related the methylation frequency to the gene expression level. Inhibition of CpG methylation with 5-aza-2’-deoxycytidine led to a several fold increase in PN-1 mRNA levels, but based on the results on CpG methylation in the CpG island spanning the transcript, the effect is most likely indirect. Conclusion： We have carefully mapped the CpG methylation pattern in two CpG islands in the 5’ part of the SERPINE2 gene without finding any obvious inverse correlation between methylation frequency and expression level.展开更多
long-term,and relapsing inflammatory disorders.IBD may spontaneously grow in the colon,and in severe cases may result in tumor lesions such as invasive carcinoma in inflamed regions of the intestine.Recent epidemiolog...long-term,and relapsing inflammatory disorders.IBD may spontaneously grow in the colon,and in severe cases may result in tumor lesions such as invasive carcinoma in inflamed regions of the intestine.Recent epidemiological reports indicate that old age and underlying diseases such as IBD contribute to severity and mortality in patients with coronavirus disease 2019(COVID-19).Currently,the ongoing COVID-19 pandemic caused serious morbidity and mortality worldwide.It has also been shown that the transmembrane serine protease 2 is an essential factor for viral activation and viral engulfment.Generally,viral entry causes a'cytokine storm'that induces excessive generation of proinflammatory cytokines/chemokines including interleukin(IL)-6,IL-2,IL-7,tumor necrosis factor-α,and interferon-γ.Future research could concentrate on developing inflammatory immunological responses that are efficient to encounter COVID-19.Current analysis elucidates the role of inflammation and immune responses during IBD infection with COVID-19 and provides a list of possible targets for IBD-regulated therapies in particular.Data from clinical,in vitro,and in vivo studies were collected in English from PubMed,Google Scholar,Scopus,and the Cochrane library until May 2021.展开更多
Coronaviruses caused an outbreak pandemic disease characterized by a severe acute respiratory distress syndrome leading to the infection of more than 200 million patients and the death of more than 4 million individua...Coronaviruses caused an outbreak pandemic disease characterized by a severe acute respiratory distress syndrome leading to the infection of more than 200 million patients and the death of more than 4 million individuals.The primary treatment is either supportive or symptomatic.Natural products have an important role in the development of various drugs.Thus,screening of natural compounds with reported antiviral activities can lead to the discovery of potential inhibitory entities against coronaviruses.In the current study,an in-silico molecular docking experiment was conducted on the effects of some of these natural antiviral phytoconstituents,(e.g.,procyanidin B2,theaflavin,quercetin,ellagic acid,caffeoylquinic acid derivatives,berginin,eudesm-1β,6α,11-triol and arbutin),on the crystal structure of SARS-CoV-2 main protease(PDB ID:6w63)using AutoDock-Vina software.Many of the docked compounds revealed good binding affinity,with procyanidin B2(–8.6 Kcal/mol)and theaflavin(–8.5 Kcal/mol)showing a better or similar binding score as the ligand(–8.5 Kcal/mol).Molecular dynamics simulations were carried out at 100 ns and revealed that procyanidin B2 forms a more stable complex with SARS-CoV-2 main protease than theaflavin.Procyanidin B2,theaflavin,and 4,5-dicaffeoylquinic acid were evaluated for toxicity by ProTox-II webserver and were non-toxic according to the predicted LD50 values and safe on different organs and pathways.Additionally,these phytoconstituents showed good ADME properties and acceptable lipophilicity,as evaluated using WLOGP.Amongst the tested compounds,procyanidin B2 showed the highest lipophilic value.It is worth mentioning that these natural inhibitiors of SARS-CoV-2 main protease are components of green and black tea that can be used as a supporting supplement for COVID patients or as potential nuclei for further drug design and development campaigns.展开更多
Objective： The aim of the study was to detect the levels of mannose-binding lectin （MBL）, MBL-associated serine protease 2 （MASP-2） and explore the clinical significances of them in patients with primary thyroid ...Objective： The aim of the study was to detect the levels of mannose-binding lectin （MBL）, MBL-associated serine protease 2 （MASP-2） and explore the clinical significances of them in patients with primary thyroid neoplasms. Methods： By using ELISA method, we detected the serum levels of MBL and MASP-2 in 26 patients with papillary thyroid carcinoma （PTC）, 30 patients with thyroid adenoma （TA） and 26 healthy people, respectively. Results： Serum MBL level was （565.23 ± 76.70） μg/L in PTCs higher than （324.267 ±24.74） μg/L in TAs, and （152.69± 16.95） IJg/L in healthy of controlling group. There was statistical significance between PTC and TA （P 〈 0.05）, however there was no difference between TA and healthy （P 〉 0.05）. Serum MASP-2 level was （726.153± 78.88） pg/L in PTCs higher than （379.266 ± 30.26） μg/L in TAs, and （203.846 ± 29.09） μg/L in healthy. Serum MASP-2 level was higher in PTCs than TAs, and the difference had statistical significance （P 〈 0.01）. But no difference was observed between in TAs and healthy. Conclusion： These findings might reflect inflammatory processes induced by defense mechanisms, in response to the development of the turnout. MBL may also be involved in the elimination of possible tumourigenic pathogens.展开更多
Objective:To explore the effect of the protease inhibitor from Agaricus bisporus(J.E.Lange)Imbach(AbPI)on glucose uptake and oxidative stress in 3 T3-L1 adipocytes.Methods:Adipocytes were differentiated and stained wi...Objective:To explore the effect of the protease inhibitor from Agaricus bisporus(J.E.Lange)Imbach(AbPI)on glucose uptake and oxidative stress in 3 T3-L1 adipocytes.Methods:Adipocytes were differentiated and stained with OilRed-O staining to confirm adipogenesis.The toxic/protective effect of AbPI on the adipocytes was determined by MTT assay,intracellular reactive oxygen species generation through flow cytometry,and morphologically through confocal microscopy using propidium iodide,4,6-diamino-2-phenylindol dihydrochloride,and 2’,7’-dichlorofluorescein diacetate dyes.The uptake of fluorescent glucose analog,2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose by adipocytes was also studied through confocal microscopy.Results:MTT assay showed that the cell survival rate was(28.00±3.00)%,(92.33±2.60)%,and(71.34±2.10)%in the presence of 2 mM H2O2,AbPI alone,and AbPI and H2O2 both,respectively,in comparison to the control.Oil-Red-O staining indicated that Ab PI enhanced adipogenesis.AbPI stimulated the glucose uptake by adipocytes similar to the drug rosiglitazone,and showed insulinsensitizing effect in the presence of insulin,but failed to stimulate the uptake in the absence of insulin.Intracellular reactive oxygen species generation was reduced in differentiating adipocytes upon Ab PI treatment.Confocal microscopy showed that the damaged cell population rose to 3.50%,117.84%,and 261.50%in the presence of Ab PI alone,AbPI with H2O2,and H2O2 alone,respectively.Conclusions:The protease inhibitor enhances glucose uptake by adipocytes and exhibits a cytoprotective effect on them.展开更多
The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study...The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study,computational approaches were employed,mainly the structure-based virtual screening coupled with all-atom molecular dynamics(MD)simulations to computationally identify specific inhibitors of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2)PLpro,which can be further developed as potential pan-PLprobased broad-spectrum antiviral drugs.The sequence,structure,and functional conserveness of most deadly human Co Vs PLprowere explored,and it was revealed that functionally important catalytic triad residues are well conserved among SARS-Co V,SARS-Co V-2,and middle east respiratory syndrome coronavirus(MERS-Co V).The subsequent screening of a focused protease inhibitors database composed of^7,000 compounds resulted in the identification of three candidate compounds,ADM13083841,LMG15521745,and SYN15517940.These three compounds established conserved interactions which were further explored through MD simulations,free energy calculations,and residual energy contribution estimated by MM-PB(GB)SA method.All these compounds showed stable conformation and interacted well with the active residues of SARS-Co V-2 PLpro,and showed consistent interaction profile with SARS-Co V PLproand MERS-Co V PLproas well.Conclusively,the reported SARS-Co V-2 PLprospecific compounds could serve as seeds for developing potent pan-PLprobased broad-spectrum antiviral drugs against deadly human coronaviruses.Moreover,the presented information related to binding site residual energy contribution could lead to further optimization of these compounds.展开更多
基金National Institutes of Health(NIH)(grants R01 A/130092 and Al161085).
文摘The spike protein(S)of SARS-CoV-2 is responsible for viral attachment and entry,thus a major factor for host suscep-tibility,tissue tropism,virulence and pathogenicity.The S is divided with S1 and S2 region,and the S1 contains the receptor-binding domain(RBD),while the S2 contains the hydrophobic fusion domain for the entry into the host cell.Numerous host proteases have been implicated in the activation of SARS-CoV-2 S through various c leavage sites.In this article,we review host proteases including furin,trypsin,transmembrane protease serine 2(TMPRSS2)and cathepsins in the activation of SARS-CoV-2 S.Many betacoronaviruses including SARS-CoV-2 have polybasic residues at the S1/S2 site which is subjected to the cleavage by furin.The S1/S2 cleavage facilitates more assessable RBD to the receptor ACE2,and the binding triggers further conformational changes and exposure of the S2'site to proteases such as type Il transmembrane serine proteases(TTPRs)including TMPRSS2.In the presence of TMPRSS2 on the target cells,SARS-CoV-2 can utilize a direct entry route by fusion of the viral envelope to the cellular membrane.In the absence of TMPRSS2,SARS-CoV-2 enter target cells via endosomes where multiple cathepsins cleave the S for the successful entry.Additional host proteases involved in the cleavage of the S were discussed.This article also includes roles of 3C-like protease inhibitors which have inhibitory activity against cathepsin L in the entry of SARS-CoV-2,and discussed the dual roles of such inhibitors in virus replication.
文摘Toll-like receptor 4(TLR4) and protease-activated receptor 2(PAR2) play pivotal roles in the mammalian innate immune response.Notably,in addition to their involvement in detection of invading pathogens,PAR2 and TLR4 modulate the levels of cell death-induced sterile inflammation by activating pro-or anti-inflammatory downstream signaling cascades.Within the central nervous system,there is emerging evidence that both receptors are involved in synaptic transmission and brain plasticity.Furthermore,due to their prominent role in mediating neuroinflammation,PAR2 and TLR4 are associated with development and progression of neurodegenerative disorders including but not limited to Alzheimer's disease,Parkinson's disease and multiple sclerosis.In this article,we summarise the current knowledge on the cooperation between PAR2 and TLR4,discuss the potential cross-talk levels and highlight the impact of the cross-coupling on neuroinflammation.
文摘Objective Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the causative agent for coronavirus disease 2019(COVID-19),is responsible for the recent global pandemic.As there are no effective drugs or vaccines available for SARS-CoV-2,we investigated the potential of flavonoids against SARS-CoV-2 main protease 6YNQ.Methods In silico molecular simulation study against SARS-CoV-2 main protease 6YNQ.Results Among the 21 selected flavonoids,rutin demonstrated the highest binding energy(−8.7 kcal/mol)and displayed perfect binding with the catalytic sites.Conclusions Our study demonstrates the inhibitory potential of flavonoids against SARS-CoV-2 main protease 6YNQ.These computational simulation studies support the hypothesis that flavonoids might be helpful for the treatment of COVID-19.
文摘Summary： The role of protease activated receptor-2 （PAR-2） in the renal tubulointerstitial lesion induced by unilateral ureteral obstruction （UUO） was explored. Mice were sacrificed on the day 1, 3, 5, 7, 10, 14 and 21 after UUO. The expression of PAR-2 mRNA and protein and a-smooth muscle actin （α-SMA） protein in tubuloin,terstitium was detected by RT-PCR and immunohistochemistry at each time point, respedtively. The results showed that the PAR-2 expression in renal tubulointerstitium was increased progressively starting from 24 h to the day 14 post-ligation, and it was significantly associated with the relative volume of interstitium and the positive area of α-SMA. PAR-2 was mainly expressed in renal tubule epithelial cells, especially in proximal tubular cells. It also located in renal capillary ansa, interstitial infiltrate cells and fibroblasts. It was concluded that PAR-2 was active in interstitial and tubular cells in the early phase of fibrotic process and played an important role in mediating the tubulointerstitial lesion after UUO.
基金supported by the Danish National Research Foundation (26-331-6)the Danish Cancer Society (DP 07043, DP 08001)Grosserer Alfred Nielsen and Hustrus Fond
文摘Objective： To investigated whether epigenetic mechanisms contribute to the variable expression of variable protease nexin1（PN-1） encoded by the SERPINE2 gene in different cell types. Methods： Working with 5 human cell lines, we determined the CpG methylation status within two CpG islands in the SERPINE2 gene by bisulphate sequencing and the PN-1 mRNA level by Q-RT PCR. Results： A CpG island spanning the transcription initiation site showed little methylation in 3 of the cell lines and substantial methylation in 2 of the cell lines. A CpG island covering the translation starting site showed full methylation in all investigated cell lines. Methylation within the CpG island was not randomly distributed, but showed accumulation at specific sites. However, we were not able to distinguish any patterns which related the methylation frequency to the gene expression level. Inhibition of CpG methylation with 5-aza-2’-deoxycytidine led to a several fold increase in PN-1 mRNA levels, but based on the results on CpG methylation in the CpG island spanning the transcript, the effect is most likely indirect. Conclusion： We have carefully mapped the CpG methylation pattern in two CpG islands in the 5’ part of the SERPINE2 gene without finding any obvious inverse correlation between methylation frequency and expression level.
文摘long-term,and relapsing inflammatory disorders.IBD may spontaneously grow in the colon,and in severe cases may result in tumor lesions such as invasive carcinoma in inflamed regions of the intestine.Recent epidemiological reports indicate that old age and underlying diseases such as IBD contribute to severity and mortality in patients with coronavirus disease 2019(COVID-19).Currently,the ongoing COVID-19 pandemic caused serious morbidity and mortality worldwide.It has also been shown that the transmembrane serine protease 2 is an essential factor for viral activation and viral engulfment.Generally,viral entry causes a'cytokine storm'that induces excessive generation of proinflammatory cytokines/chemokines including interleukin(IL)-6,IL-2,IL-7,tumor necrosis factor-α,and interferon-γ.Future research could concentrate on developing inflammatory immunological responses that are efficient to encounter COVID-19.Current analysis elucidates the role of inflammation and immune responses during IBD infection with COVID-19 and provides a list of possible targets for IBD-regulated therapies in particular.Data from clinical,in vitro,and in vivo studies were collected in English from PubMed,Google Scholar,Scopus,and the Cochrane library until May 2021.
文摘Coronaviruses caused an outbreak pandemic disease characterized by a severe acute respiratory distress syndrome leading to the infection of more than 200 million patients and the death of more than 4 million individuals.The primary treatment is either supportive or symptomatic.Natural products have an important role in the development of various drugs.Thus,screening of natural compounds with reported antiviral activities can lead to the discovery of potential inhibitory entities against coronaviruses.In the current study,an in-silico molecular docking experiment was conducted on the effects of some of these natural antiviral phytoconstituents,(e.g.,procyanidin B2,theaflavin,quercetin,ellagic acid,caffeoylquinic acid derivatives,berginin,eudesm-1β,6α,11-triol and arbutin),on the crystal structure of SARS-CoV-2 main protease(PDB ID:6w63)using AutoDock-Vina software.Many of the docked compounds revealed good binding affinity,with procyanidin B2(–8.6 Kcal/mol)and theaflavin(–8.5 Kcal/mol)showing a better or similar binding score as the ligand(–8.5 Kcal/mol).Molecular dynamics simulations were carried out at 100 ns and revealed that procyanidin B2 forms a more stable complex with SARS-CoV-2 main protease than theaflavin.Procyanidin B2,theaflavin,and 4,5-dicaffeoylquinic acid were evaluated for toxicity by ProTox-II webserver and were non-toxic according to the predicted LD50 values and safe on different organs and pathways.Additionally,these phytoconstituents showed good ADME properties and acceptable lipophilicity,as evaluated using WLOGP.Amongst the tested compounds,procyanidin B2 showed the highest lipophilic value.It is worth mentioning that these natural inhibitiors of SARS-CoV-2 main protease are components of green and black tea that can be used as a supporting supplement for COVID patients or as potential nuclei for further drug design and development campaigns.
基金Supported by a grant of Natural Science Funds Projects of Hebei Province (No. C2008001306)
文摘Objective： The aim of the study was to detect the levels of mannose-binding lectin （MBL）, MBL-associated serine protease 2 （MASP-2） and explore the clinical significances of them in patients with primary thyroid neoplasms. Methods： By using ELISA method, we detected the serum levels of MBL and MASP-2 in 26 patients with papillary thyroid carcinoma （PTC）, 30 patients with thyroid adenoma （TA） and 26 healthy people, respectively. Results： Serum MBL level was （565.23 ± 76.70） μg/L in PTCs higher than （324.267 ±24.74） μg/L in TAs, and （152.69± 16.95） IJg/L in healthy of controlling group. There was statistical significance between PTC and TA （P 〈 0.05）, however there was no difference between TA and healthy （P 〉 0.05）. Serum MASP-2 level was （726.153± 78.88） pg/L in PTCs higher than （379.266 ± 30.26） μg/L in TAs, and （203.846 ± 29.09） μg/L in healthy. Serum MASP-2 level was higher in PTCs than TAs, and the difference had statistical significance （P 〈 0.01）. But no difference was observed between in TAs and healthy. Conclusion： These findings might reflect inflammatory processes induced by defense mechanisms, in response to the development of the turnout. MBL may also be involved in the elimination of possible tumourigenic pathogens.
文摘Objective:To explore the effect of the protease inhibitor from Agaricus bisporus(J.E.Lange)Imbach(AbPI)on glucose uptake and oxidative stress in 3 T3-L1 adipocytes.Methods:Adipocytes were differentiated and stained with OilRed-O staining to confirm adipogenesis.The toxic/protective effect of AbPI on the adipocytes was determined by MTT assay,intracellular reactive oxygen species generation through flow cytometry,and morphologically through confocal microscopy using propidium iodide,4,6-diamino-2-phenylindol dihydrochloride,and 2’,7’-dichlorofluorescein diacetate dyes.The uptake of fluorescent glucose analog,2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose by adipocytes was also studied through confocal microscopy.Results:MTT assay showed that the cell survival rate was(28.00±3.00)%,(92.33±2.60)%,and(71.34±2.10)%in the presence of 2 mM H2O2,AbPI alone,and AbPI and H2O2 both,respectively,in comparison to the control.Oil-Red-O staining indicated that Ab PI enhanced adipogenesis.AbPI stimulated the glucose uptake by adipocytes similar to the drug rosiglitazone,and showed insulinsensitizing effect in the presence of insulin,but failed to stimulate the uptake in the absence of insulin.Intracellular reactive oxygen species generation was reduced in differentiating adipocytes upon Ab PI treatment.Confocal microscopy showed that the damaged cell population rose to 3.50%,117.84%,and 261.50%in the presence of Ab PI alone,AbPI with H2O2,and H2O2 alone,respectively.Conclusions:The protease inhibitor enhances glucose uptake by adipocytes and exhibits a cytoprotective effect on them.
基金the Starting Research Grant for High-level Talents from Guangxi Universitythe Postdoctoral Project from Guangxi University。
文摘The papain-like protease(PLpro)is vital for the replication of coronaviruses(Co Vs),as well as for escaping innate-immune responses of the host.Hence,it has emerged as an attractive antiviral drug-target.In this study,computational approaches were employed,mainly the structure-based virtual screening coupled with all-atom molecular dynamics(MD)simulations to computationally identify specific inhibitors of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2)PLpro,which can be further developed as potential pan-PLprobased broad-spectrum antiviral drugs.The sequence,structure,and functional conserveness of most deadly human Co Vs PLprowere explored,and it was revealed that functionally important catalytic triad residues are well conserved among SARS-Co V,SARS-Co V-2,and middle east respiratory syndrome coronavirus(MERS-Co V).The subsequent screening of a focused protease inhibitors database composed of^7,000 compounds resulted in the identification of three candidate compounds,ADM13083841,LMG15521745,and SYN15517940.These three compounds established conserved interactions which were further explored through MD simulations,free energy calculations,and residual energy contribution estimated by MM-PB(GB)SA method.All these compounds showed stable conformation and interacted well with the active residues of SARS-Co V-2 PLpro,and showed consistent interaction profile with SARS-Co V PLproand MERS-Co V PLproas well.Conclusively,the reported SARS-Co V-2 PLprospecific compounds could serve as seeds for developing potent pan-PLprobased broad-spectrum antiviral drugs against deadly human coronaviruses.Moreover,the presented information related to binding site residual energy contribution could lead to further optimization of these compounds.
