Objective: In the present study we evaluated the paraoxonase activity and protein thiols level in south Indian population with newly diagnosed hyperlipidemia.Methods: The study was conducted on 55 newly diagnosed hype...Objective: In the present study we evaluated the paraoxonase activity and protein thiols level in south Indian population with newly diagnosed hyperlipidemia.Methods: The study was conducted on 55 newly diagnosed hyperlipidemic patients and 57 healthy controls.Serum paraoxonase activity and protein thiols were estimated by spectrophotometeric method and lipid profile by enzymatic kinetic assay method.Results: Serum paraoxonase activity,protein thiols and high density lipoprotein levels were low and total cholesterol,triglycerides and low density lipoprotein levels were high in patients with hyperlipidemia compared to healthy controls(P<0.01).Serum paraoxonase activity correlated positively with protein thiols and high density lipoprotein(P<0.01).Conclusion: Decreased paraoxonase activity and protein thiols were found in patients with hyperlipidemia.This may indicate the susceptibility of this population to accelerated atherogenesis and protein oxidation.展开更多
Objective:To measure serum copper and protein thiols along with lipid profile in hyperlipidemic patients and to establish the relationship between serum copper,protein thiols and lipid profile parameters.Methods: The ...Objective:To measure serum copper and protein thiols along with lipid profile in hyperlipidemic patients and to establish the relationship between serum copper,protein thiols and lipid profile parameters.Methods: The study group consisted of 26 newly diagnosed hyperlipidemic patients not associated with any other systemic diseases and 26 age and sex matched healthy controls.Fasting lipid profile was done by enzymatic method using automated analyzer.Serum copper and protein thiols were measured spectrophotometrically.Results: Serum copper and protein-SH levels were significantly decreased in cases(P<0.01,P<0.01) compared to controls.Serum copper correlated positively with protein thiols(r=0.800,P<0.01) and negatively with LDL cholesterol(r=-0.351 P<0.05).Conclusion: Serum copper and protein thiols were decreased in hyperlipidemia and they correlated positively indicating protective role of copper in preventing homocysteinylation of protein and hence in preventing atherosclerosis.展开更多
Objective:Bilirubin is a double edged sword in biological system,acting as a toxic molecule and cytoprotectant.Unconjugated bilirubin is proved to show antioxidant activity in vitro and in vivo.In the current work we ...Objective:Bilirubin is a double edged sword in biological system,acting as a toxic molecule and cytoprotectant.Unconjugated bilirubin is proved to show antioxidant activity in vitro and in vivo.In the current work we tried to know the relationship between both conjugated and unconjugated bilirubin with copper and protein thiols in patients with hyperbilirubinemia.Methods:Study was conducted on 56 hyperbilirubinemic cases and 56 healthy controls.Serum copper,ceruloplasmin,protein thiols,total bilirubin,conjugated and unconjugated bilirubin,unconjugated bilirubin/albumin ratio,total protein,albumin,AST,ALT and ALP were estimated.Results:There was significant increase in serum copper,total bilirubin,conjugated and unconjugated bilirubin,unconjugated bilirubin/albumin ratio,AST,ALT,and ALP,and decrease in serum ceruloplasmin,protein thiols,total protein,and albumin in hyperbilirubinemic cases when compared to healthy controls.Conjugated bilirubin correlated positively with liver enzymes AST and ALP,and negatively with protein thiols,total protein and albumin.Unconjugated bilirubin correlated positively with ALT.Protein thiols correlated negatively with copper and positively with ceruloplasmin,and also correlated negatively with liver enzymes like AST,ALT and ALP,and positively with total protein and albumin.Conclusion:Combination of elevated levels of trace elements like copper and availability of reducing agent like bilirubin may prove deleterious by generating free radicals.展开更多
The vicinal dithiol motif is widely present in proteins, and is critical for proteins’ structures and functions.In recent years, a variety of fluorescent probes with high specificity and outstanding optical propertie...The vicinal dithiol motif is widely present in proteins, and is critical for proteins’ structures and functions.In recent years, a variety of fluorescent probes with high specificity and outstanding optical properties for sensing protein vicinal dithiols have been developed. In this review, we summarized the fluorescent probes of protein vicinal dithiols in literature. These probes are classified into four types based on their acceptor sites, i.e., biarsenical probes, monoarsenical probes, dimaleimide probes and diacrylate probes.Through analyzing the properties of different probes, we expect that this review would help readers further understand the structural factors of these probes and provide the design strategy for novel fluorescent probes with improved properties.展开更多
The redox state of cellular thiols is widely studied because it was recently linked to many different diseases and pathologies. In this work we quantified the concentrations of protein disulfides (PSSP) and thiol-prot...The redox state of cellular thiols is widely studied because it was recently linked to many different diseases and pathologies. In this work we quantified the concentrations of protein disulfides (PSSP) and thiol-protein mixed disulfides (XSSP) in rat tissues (liver, kidney and heart) and cells (Raw 264.7) by an improved method of XSSP and PSSP determination after oxidative stress induced by diamide. Under native and denaturing conditions, a thiol block by N-ethymaleimide was introduced to avoid thiol exchange reaction activations by protein SH groups (PSH) (PSH + XSSP ←→ PSSP + XSH) and alterations of original XSSP/PSSP levels. Low molecular weight thiols (XSH) and PSH were respectively measured by HPLC on supernatants and on corresponding pellets by DTNB (Ellman’s reagent) after dithiothreitol reduction. PSSP concentrations of liver, heart and kidney were respectively 0.304, 0.605 and 0.785 μmoles/g and after diamide exposure they were significantly augmented of about 65%-70% in liver and heart, but not in the kidney. Normal XSSP, that were -20 times lower than normal PSSP were induced by diamide in liver and heart of about 40 times, but not in kidney. Thermodynamic criteria regarding the pKa values of thiols engaged as PSSP and GSSP were used to interpret dethiolation mechanisms via thiol exchange reactions.展开更多
AIM： To investigate the role of major non-protein and protein sulfhydryls and disulfides in chemically induced gastric hemorrhagic mucosal lesions （HML） and the mechanism of gastroprotective effect of sucralfate.ME...AIM： To investigate the role of major non-protein and protein sulfhydryls and disulfides in chemically induced gastric hemorrhagic mucosal lesions （HML） and the mechanism of gastroprotective effect of sucralfate.METHODS： Rats were given 1 mL of 75% ethanol, 25%NaCl, 0.6 mol/L HCI, 0.2 mol/L NaOH or 1% ammonia solutions intragastrically （i.g.） and sacrificed 1, 3, 6 or 12 min later. Total （reduced and oxidized） glutathione （GSH ＋ GSSG）, glutathione disulfide （GSSG）, protein free sulfhydryls （PSH）, protein-glutathione mixed disulfides （PSSG） and protein cystine disulfides （PSSP） were measured in gastric mucosa and liver.RESULTS： Reduced glutathione （GSH） was depleted in the gastric mucosa after ethanol, HCI or NaCl exposure,while oxidized glutathione （GSSG） concentrations increased, except by HCI and NaOH exposure. Decreased levels of PSH after exposure to ethanol were observed,NaCl or NaOH while the total protein disulfides were increased. Ratios of reduced to oxidized glutathione or sulfhydrils to disulfides were decreased by all chemicals.No changes in thiol homeostasis were detected in the liver after i.g. abbreviation should be spelled out the first time here administration of ethanol. Sucralfate increased the concentrations of GSH and PSH and prevented the ethanol-induced changes in gastric mucosal thiol concentrations.CONCLUSION： Our modified methods are now suitable for direct measurements of major protein and nonprotein thiols/disulfides in the gastric mucosa or liver.A common element in the pathogenesis of chemically induced HML and in the mechanism of gastroprotective drugs seems to be the decreased ratios of reduced and oxidized glutathione as well as protein sulfhydryls and disulfides.展开更多
Objective:To explore whether oxidative stress has any role in premenstrual syndrome(PMS). Methods:Female volunteers suffering from PMS,in the age group of 20-24 years were compared to their asymptomatic normomennorhoe...Objective:To explore whether oxidative stress has any role in premenstrual syndrome(PMS). Methods:Female volunteers suffering from PMS,in the age group of 20-24 years were compared to their asymptomatic normomennorhoeic counterparts in follicular phase and late luteal phase for ferric reducing antioxidant power of plasma(FRAP),plasma protein thiols(PPT) and protein carbonyls(PPC) levels.Results:There was no significant change in FRAP and PPC levels in controls and PMS groups but PPT decreased significantly in luteal phase of PMS(P【 0.05) when compared to follicular phase.Conclusions:Estrogen and progesterone,might be responsible for a healthy antioxidant profile in PMS.However,a marked decrease in PPT in luteal phase of PMS group may be due to pro-oxidant nature of estrogen-active in this phase of PMS leading to consumption of the sacrificial antioxidant-protein thiol.展开更多
Understanding the based-on drug or drug conjugates to reach the beneficial optimally recognized by the immune system requires multidisciplinary approaches and detailed of albumin as the key circulating a transporting/...Understanding the based-on drug or drug conjugates to reach the beneficial optimally recognized by the immune system requires multidisciplinary approaches and detailed of albumin as the key circulating a transporting/transmission and antioxidant protein of blood drug interaction. Albumin, in reduced form (mercaptoalbumin, HMA), with antioxidant ability and alterations/deteriorations in the redox status of human serum albumin (HSA) under oxidative stress formation in infection diseases and its complications strongly modifies albumin antioxidant capacity. The aim of this study was the investigation of carbonyl/oxidative stress and pseudo-esterase activity of mercaptolbumin and oxidized HSA models. HSA (P. pastoris) purchased from MedChemExpress (USA) was used for study to model oxidative stress, HSA in reduced (intact) form was treated with H2O2, tert-butylhydroperoxide (t-BHP) and chloramine T (CT). The content of HSA-bound carbonyl groups decreased in under treatment with t-BPH- and CT-reduced HSA and more less extent in case of H2O2-treated. Fatty acid-free HSA and mercaptoalbumin (HMA) advanced oxidation protein products (AOPP) concentrations were significantly lower than in H2O2 loading reduced HSA by 123% and 235%, respectively. The total thiols level was lower in HMA + CT compared to reduced HMA by 51% and even increased after treatment of HMA with H2O2. Pseudo-esterase activity of HMA maintains >65% in the presence of hydroperoxide and occurs pronounced loss in the presence of chloramine T. Hydrogen peroxide at physiological concentration about 10 μM occurs less damage of reduced from of HSA then t-BPH and CT, and unlike t-BPH and CT, without significantly changes in pseudo-esterase activities.展开更多
The effect of calcium chloride （CaCl2） on rice seedling growth under cadmium chloride （CdCl2） stress, as well as the possible role of endogenous nitric oxide （NO） in this process, was studied. The growth of rice...The effect of calcium chloride （CaCl2） on rice seedling growth under cadmium chloride （CdCl2） stress, as well as the possible role of endogenous nitric oxide （NO） in this process, was studied. The growth of rice seedlings was seriously inhibited by CdCl2, and the inhibition was significantly mitigated by CaCl2. However, hemoglobin （Hb） and 2-（4-carboxyphenyl）-4, 4,5,5-tetramethylimidazoline- l-oxyl-3-oxide （cPTIO） weakened the promotion effect of CaCl2. The results of NO fluorescence localization suggest that growth accelerated by CaCl2 might be associated with elevated NO levels. The content of Cd, protein thiols （PBT）, and nonprotein thiols （NPT） in cell walls, cell organelles, and soluble fractions, respectively, of rice seedlings decreased considerably in the presence of CaCl2, whereas the content of pectin, hemicellulose 1 （HC1）, and hemicellulose 2 （HC2） increased significantly. Elimination of endogenous NO in Cd＋Ca treatment could promote the transportation of Cd2＋ to cell organelles and soluble fractions and increase the content of NPT and PBT in leaves. In addition, transportation of Cd2＋ to cell organelles and soluble fractions was retarded in roots, the content of NPT increased, and the content of PBT decreased. With elimination of endogenous NO in Cd＋Ca treatment, the content of pectin, HC1, and HC2 decreased significantly. Thus, Ca may alleviate Cd toxicity via endogenous NO with variation in the levels of NPT, PBT, and matrix polysaccharides.展开更多
文摘Objective: In the present study we evaluated the paraoxonase activity and protein thiols level in south Indian population with newly diagnosed hyperlipidemia.Methods: The study was conducted on 55 newly diagnosed hyperlipidemic patients and 57 healthy controls.Serum paraoxonase activity and protein thiols were estimated by spectrophotometeric method and lipid profile by enzymatic kinetic assay method.Results: Serum paraoxonase activity,protein thiols and high density lipoprotein levels were low and total cholesterol,triglycerides and low density lipoprotein levels were high in patients with hyperlipidemia compared to healthy controls(P<0.01).Serum paraoxonase activity correlated positively with protein thiols and high density lipoprotein(P<0.01).Conclusion: Decreased paraoxonase activity and protein thiols were found in patients with hyperlipidemia.This may indicate the susceptibility of this population to accelerated atherogenesis and protein oxidation.
文摘Objective:To measure serum copper and protein thiols along with lipid profile in hyperlipidemic patients and to establish the relationship between serum copper,protein thiols and lipid profile parameters.Methods: The study group consisted of 26 newly diagnosed hyperlipidemic patients not associated with any other systemic diseases and 26 age and sex matched healthy controls.Fasting lipid profile was done by enzymatic method using automated analyzer.Serum copper and protein thiols were measured spectrophotometrically.Results: Serum copper and protein-SH levels were significantly decreased in cases(P<0.01,P<0.01) compared to controls.Serum copper correlated positively with protein thiols(r=0.800,P<0.01) and negatively with LDL cholesterol(r=-0.351 P<0.05).Conclusion: Serum copper and protein thiols were decreased in hyperlipidemia and they correlated positively indicating protective role of copper in preventing homocysteinylation of protein and hence in preventing atherosclerosis.
文摘Objective:Bilirubin is a double edged sword in biological system,acting as a toxic molecule and cytoprotectant.Unconjugated bilirubin is proved to show antioxidant activity in vitro and in vivo.In the current work we tried to know the relationship between both conjugated and unconjugated bilirubin with copper and protein thiols in patients with hyperbilirubinemia.Methods:Study was conducted on 56 hyperbilirubinemic cases and 56 healthy controls.Serum copper,ceruloplasmin,protein thiols,total bilirubin,conjugated and unconjugated bilirubin,unconjugated bilirubin/albumin ratio,total protein,albumin,AST,ALT and ALP were estimated.Results:There was significant increase in serum copper,total bilirubin,conjugated and unconjugated bilirubin,unconjugated bilirubin/albumin ratio,AST,ALT,and ALP,and decrease in serum ceruloplasmin,protein thiols,total protein,and albumin in hyperbilirubinemic cases when compared to healthy controls.Conjugated bilirubin correlated positively with liver enzymes AST and ALP,and negatively with protein thiols,total protein and albumin.Unconjugated bilirubin correlated positively with ALT.Protein thiols correlated negatively with copper and positively with ceruloplasmin,and also correlated negatively with liver enzymes like AST,ALT and ALP,and positively with total protein and albumin.Conclusion:Combination of elevated levels of trace elements like copper and availability of reducing agent like bilirubin may prove deleterious by generating free radicals.
基金financial supports from the National Natural Science Foundation of China (Nos. 21572093 & 21778028)the 111 Project
文摘The vicinal dithiol motif is widely present in proteins, and is critical for proteins’ structures and functions.In recent years, a variety of fluorescent probes with high specificity and outstanding optical properties for sensing protein vicinal dithiols have been developed. In this review, we summarized the fluorescent probes of protein vicinal dithiols in literature. These probes are classified into four types based on their acceptor sites, i.e., biarsenical probes, monoarsenical probes, dimaleimide probes and diacrylate probes.Through analyzing the properties of different probes, we expect that this review would help readers further understand the structural factors of these probes and provide the design strategy for novel fluorescent probes with improved properties.
文摘The redox state of cellular thiols is widely studied because it was recently linked to many different diseases and pathologies. In this work we quantified the concentrations of protein disulfides (PSSP) and thiol-protein mixed disulfides (XSSP) in rat tissues (liver, kidney and heart) and cells (Raw 264.7) by an improved method of XSSP and PSSP determination after oxidative stress induced by diamide. Under native and denaturing conditions, a thiol block by N-ethymaleimide was introduced to avoid thiol exchange reaction activations by protein SH groups (PSH) (PSH + XSSP ←→ PSSP + XSH) and alterations of original XSSP/PSSP levels. Low molecular weight thiols (XSH) and PSH were respectively measured by HPLC on supernatants and on corresponding pellets by DTNB (Ellman’s reagent) after dithiothreitol reduction. PSSP concentrations of liver, heart and kidney were respectively 0.304, 0.605 and 0.785 μmoles/g and after diamide exposure they were significantly augmented of about 65%-70% in liver and heart, but not in the kidney. Normal XSSP, that were -20 times lower than normal PSSP were induced by diamide in liver and heart of about 40 times, but not in kidney. Thermodynamic criteria regarding the pKa values of thiols engaged as PSSP and GSSP were used to interpret dethiolation mechanisms via thiol exchange reactions.
文摘AIM： To investigate the role of major non-protein and protein sulfhydryls and disulfides in chemically induced gastric hemorrhagic mucosal lesions （HML） and the mechanism of gastroprotective effect of sucralfate.METHODS： Rats were given 1 mL of 75% ethanol, 25%NaCl, 0.6 mol/L HCI, 0.2 mol/L NaOH or 1% ammonia solutions intragastrically （i.g.） and sacrificed 1, 3, 6 or 12 min later. Total （reduced and oxidized） glutathione （GSH ＋ GSSG）, glutathione disulfide （GSSG）, protein free sulfhydryls （PSH）, protein-glutathione mixed disulfides （PSSG） and protein cystine disulfides （PSSP） were measured in gastric mucosa and liver.RESULTS： Reduced glutathione （GSH） was depleted in the gastric mucosa after ethanol, HCI or NaCl exposure,while oxidized glutathione （GSSG） concentrations increased, except by HCI and NaOH exposure. Decreased levels of PSH after exposure to ethanol were observed,NaCl or NaOH while the total protein disulfides were increased. Ratios of reduced to oxidized glutathione or sulfhydrils to disulfides were decreased by all chemicals.No changes in thiol homeostasis were detected in the liver after i.g. abbreviation should be spelled out the first time here administration of ethanol. Sucralfate increased the concentrations of GSH and PSH and prevented the ethanol-induced changes in gastric mucosal thiol concentrations.CONCLUSION： Our modified methods are now suitable for direct measurements of major protein and nonprotein thiols/disulfides in the gastric mucosa or liver.A common element in the pathogenesis of chemically induced HML and in the mechanism of gastroprotective drugs seems to be the decreased ratios of reduced and oxidized glutathione as well as protein sulfhydryls and disulfides.
文摘Objective:To explore whether oxidative stress has any role in premenstrual syndrome(PMS). Methods:Female volunteers suffering from PMS,in the age group of 20-24 years were compared to their asymptomatic normomennorhoeic counterparts in follicular phase and late luteal phase for ferric reducing antioxidant power of plasma(FRAP),plasma protein thiols(PPT) and protein carbonyls(PPC) levels.Results:There was no significant change in FRAP and PPC levels in controls and PMS groups but PPT decreased significantly in luteal phase of PMS(P【 0.05) when compared to follicular phase.Conclusions:Estrogen and progesterone,might be responsible for a healthy antioxidant profile in PMS.However,a marked decrease in PPT in luteal phase of PMS group may be due to pro-oxidant nature of estrogen-active in this phase of PMS leading to consumption of the sacrificial antioxidant-protein thiol.
文摘Understanding the based-on drug or drug conjugates to reach the beneficial optimally recognized by the immune system requires multidisciplinary approaches and detailed of albumin as the key circulating a transporting/transmission and antioxidant protein of blood drug interaction. Albumin, in reduced form (mercaptoalbumin, HMA), with antioxidant ability and alterations/deteriorations in the redox status of human serum albumin (HSA) under oxidative stress formation in infection diseases and its complications strongly modifies albumin antioxidant capacity. The aim of this study was the investigation of carbonyl/oxidative stress and pseudo-esterase activity of mercaptolbumin and oxidized HSA models. HSA (P. pastoris) purchased from MedChemExpress (USA) was used for study to model oxidative stress, HSA in reduced (intact) form was treated with H2O2, tert-butylhydroperoxide (t-BHP) and chloramine T (CT). The content of HSA-bound carbonyl groups decreased in under treatment with t-BPH- and CT-reduced HSA and more less extent in case of H2O2-treated. Fatty acid-free HSA and mercaptoalbumin (HMA) advanced oxidation protein products (AOPP) concentrations were significantly lower than in H2O2 loading reduced HSA by 123% and 235%, respectively. The total thiols level was lower in HMA + CT compared to reduced HMA by 51% and even increased after treatment of HMA with H2O2. Pseudo-esterase activity of HMA maintains >65% in the presence of hydroperoxide and occurs pronounced loss in the presence of chloramine T. Hydrogen peroxide at physiological concentration about 10 μM occurs less damage of reduced from of HSA then t-BPH and CT, and unlike t-BPH and CT, without significantly changes in pseudo-esterase activities.
基金supported by the Zhejiang Provincial Natural Science Foundation of China (No. Y3100246)the Innovation Team of the Safety Standards and Testing Technology for Agricultural Products of Zhejiang Province(No. 2010R50028)
文摘The effect of calcium chloride （CaCl2） on rice seedling growth under cadmium chloride （CdCl2） stress, as well as the possible role of endogenous nitric oxide （NO） in this process, was studied. The growth of rice seedlings was seriously inhibited by CdCl2, and the inhibition was significantly mitigated by CaCl2. However, hemoglobin （Hb） and 2-（4-carboxyphenyl）-4, 4,5,5-tetramethylimidazoline- l-oxyl-3-oxide （cPTIO） weakened the promotion effect of CaCl2. The results of NO fluorescence localization suggest that growth accelerated by CaCl2 might be associated with elevated NO levels. The content of Cd, protein thiols （PBT）, and nonprotein thiols （NPT） in cell walls, cell organelles, and soluble fractions, respectively, of rice seedlings decreased considerably in the presence of CaCl2, whereas the content of pectin, hemicellulose 1 （HC1）, and hemicellulose 2 （HC2） increased significantly. Elimination of endogenous NO in Cd＋Ca treatment could promote the transportation of Cd2＋ to cell organelles and soluble fractions and increase the content of NPT and PBT in leaves. In addition, transportation of Cd2＋ to cell organelles and soluble fractions was retarded in roots, the content of NPT increased, and the content of PBT decreased. With elimination of endogenous NO in Cd＋Ca treatment, the content of pectin, HC1, and HC2 decreased significantly. Thus, Ca may alleviate Cd toxicity via endogenous NO with variation in the levels of NPT, PBT, and matrix polysaccharides.
