Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted wit... more Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted with 70% acetone and analyzed for their total phenolics concentration and antioxidant potential. Seven extracts showed more than 85% inhibition of lipid peroxidation in vitro as compared with blank. Butylated hydroxytoluene (BHT) (IC50 = 233.6 microg/l +/- 28.3) was the strongest antioxidant in our test system. The IC50 results indicate that the extracts of Nymphaea lotus L. flowers, Acacia nilotica (Linn.) Delile beans, Terminalia belerica Roxb. fruits, and Terminalia chebula Retz. (fruits, brown) were stronger antioxidants than alpha-tocopherol, while Terminalia chebula Retz. (fruit coat), Terminalia chebula Retz. (fruits, black) and Ricinus communis L. leaves were weaker antioxidant extracts than alpha-tocopherol and BHT. Total phenolics concentration, expressed as gallic acid equivalents, showed close correlation with the antioxidant activity. High performance liquid chromatographic analysis with diode array detection at 280 nm, of the seven extracts indicated the presence of hydroxybenzoic acid derivatives, hydroxycinnamic acid derivatives, flavonol aglycones and their glycosides as main phenolics compounds. This information, based on quick screening methods, enables us to proceed towards more detailed chemical and pharmacological understanding of these plant materials.
Zeitschrift für Naturforschung. C, Journal of biosciences
Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted wit... more Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted with 70% acetone and analyzed for their total phenolics concentration and antioxidant potential. Seven extracts showed more than 85% inhibition of lipid peroxidation in vitro as compared with blank. Butylated hydroxytoluene (BHT) (IC50 = 233.6 microg/l +/- 28.3) was the strongest antioxidant in our test system. The IC50 results indicate that the extracts of Nymphaea lotus L. flowers, Acacia nilotica (Linn.) Delile beans, Terminalia belerica Roxb. fruits, and Terminalia chebula Retz. (fruits, brown) were stronger antioxidants than alpha-tocopherol, while Terminalia chebula Retz. (fruit coat), Terminalia chebula Retz. (fruits, black) and Ricinus communis L. leaves were weaker antioxidant extracts than alpha-tocopherol and BHT. Total phenolics concentration, expressed as gallic acid equivalents, showed close correlation with the antioxidant activity. High performance liquid chromatographic ana...
Oxidized LDL lipids (ox-LDL) are associated with lifestyle diseases such as cardiovascular diseas... more Oxidized LDL lipids (ox-LDL) are associated with lifestyle diseases such as cardiovascular diseases, metabolic syndrome and type 2 diabetes. The present study investigated how postpartum weight retention effects on ox-LDL and serum lipids. The study is a nested comparative research of a cluster-randomized controlled trial, NELLI (lifestyle and counselling during pregnancy). During early pregnancy (8-12 weeks) and 1 year postpartum, 141 women participated in measurements for determining of plasma lipids: total cholesterol (T-C), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), triacylglycerols (TAG) and ox-LDL. Subjects were stratified into tertiles (weight loss, unaltered weight and weight gain groups) based on their weight change from baseline to follow-up. Ox-LDL was determined by baseline level of conjugated dienes in LDL lipids. Among the group of weight gainers, concentration of TAG reduced less (-0.14 vs. -0.33, p = 0.002), HDL-C reduced more (-0.31 vs. -0.16, p = 0.003) and ox-LDL/HDL-C ratio increased (3.0 vs. -0.2, p = 0.003) when compared to group of weight loss. Both T-C and LDL-C elevated more (0.14 vs. -0.21, p = 0.008; 0.31 vs. 0.07, p = 0.015) and TAG and ox-LDL reduced less (-0.33 vs. 0.20, p = 0.033; -3.33 vs. -0.68, p = 0.026) in unaltered weight group compared to weight loss group. The women who gained weight developed higher TAG and ox-LDL/HDL-C ratio as compared to those who lost weight. Postpartum weight retention of 3.4 kg or more is associated with atherogenic lipid profile.
In vivo oxidation of low-density lipoprotein is shown to be significantly related to another risk... more In vivo oxidation of low-density lipoprotein is shown to be significantly related to another risk factor for coronary atherosclerosis, abnormal electrocardiographic late potentials, in clinically healthy pilots. Because both of these variables have been also associated with cardiac arrhythmogenic action, together they may improve the identification of patients at risk of ventricular tachyarrhythmias.
European Journal of Clinical Nutrition, Feb 1, 2008
Objective: To investigate the effects of stanol ester margarine use in healthy subjects on arteri... more Objective: To investigate the effects of stanol ester margarine use in healthy subjects on arterial compliance, endothelial function and intima-media thickness. Design: Case-control study comparing regular stanol ester margarine users to non-users. Setting: Occupational health service clinic. Subjects: We recruited 50 cases and 50 controls (mean age 5178, range 26-65 years). All subjects were non-smokers and the study groups were matched for age and sex. As cases, we invited subjects who had been using regularly (daily) plant stanol ester margarine for a period of 2 years or longer. Non-invasive ultrasound was used to measure carotid artery compliance, carotid intima-media thickness and brachial artery flow-mediated endothelial dependent vasodilatation. Results: The carotid artery compliance was non-significantly higher in cases compared with controls, 1.8471.02 vs 1.5870.76 %/10 mm Hg (P ¼ 0.13). The difference in compliance became statistically significant (P ¼ 0.04) when the unbalance between the groups in family history of coronary artery disease and years of education were taken into account. There was also a significant dose-response relationship between stanol margarine use and carotid compliance, longer use being associated with higher compliance. Serum lipoproteins, blood pressure, flow-mediated dilation and intima-media thickness values did not differ between cases and controls. Conclusion: These data raise the possibility that regular stanol ester margarine use may be associated with beneficial changes in arterial compliance. Intervention studies are needed to test this hypothesis and to reveal possible mechanisms.
Objective-Obesity is associated with endothelial dysfunction that may contribute to the developme... more Objective-Obesity is associated with endothelial dysfunction that may contribute to the development of atherosclerosis.
Oxygen uptake (VO2) on-kinetics is decelerated in acute hypoxia and accelerated in hyperoxia in c... more Oxygen uptake (VO2) on-kinetics is decelerated in acute hypoxia and accelerated in hyperoxia in comparison with normoxia during submaximal exercise. However, the effects of fraction of oxygen in inspired air (FIO2) on VO2 kinetics during maximal exercise are unknown. The effects of FIO2 on VO2 on-kinetics during maximal exercise are similar to submaximal exercise. There were 11 endurance athletes who were studied during maximal 7-min cycle ergometer exercise in hyperoxia (FIO2 0.325), hypoxia (FIO2 0.166) and normoxia (FIO2 0.209). The individual VO2 data were fit to a curve by using a three exponential model. In hypoxia, VO2 on-response amplitude during Phase 2 (approximately 20-100 s from the beginning of exercise) was lower (p < 0.05) when compared with hyperoxia; time constant of VO2 Phase 3 (beyond approximately 100 s after beginning of exercise) was shorter (p < 0.05) when compared with hyperoxia; and mean response time (MRT, O-63%) for VO2peak was shorter (p < 0.05) ...
Research in experimental medicine. Zeitschrift für die gesamte experimentelle Medizin einschliesslich experimenteller Chirurgie, 1999
Nitecapone (NC) has been shown to have beneficial effects on the functional recovery of rat heart... more Nitecapone (NC) has been shown to have beneficial effects on the functional recovery of rat hearts in Langendorff-preparation. The present study was executed to evaluate the effect of NC on preservation of grafts in heart transplantation and the role of NC in the inhibition of granulocyte infiltration. Donor hearts were perfused and stored at +4 degrees C for 8 h in either Ringer solution in the control-group (C-group, n = 26) or in NC (50 microM) added Ringer solution (NC-group, n = 18). The heterotopic heart transplantation was performed. The rats in both groups were killed at either 10 min or 60 min after release of the aortic clamp and tissue samples were obtained for antioxidative capacity, myeloperoxidase activity, and lipid peroxidation measurements. In vitro studies were performed using sodium azide or nitecapone to inhibit myeloperoxidase (MPO) activity of isolated human leukocytes. A total of 61% of the grafts began to beat in the NC-group, compared to 46% in the control g...
The prooxidant effect of X-irradiation on rat testis and liver tissue was studied with doses of 0... more The prooxidant effect of X-irradiation on rat testis and liver tissue was studied with doses of 0.5 and 3.0 Gy; the latter dose kills the proliferating spermatogonia and causes a maturation-depletion process in the germ cells. The level of lipid peroxidation, measured by the formation of diene conjugates and thiobarbituric acid-reactive substances (TBARS) and the activities of the antioxidant enzymes were determined 0.5 hours, 1 day, 7 days, and 31 days after the exposure. In the liver, increased levels of diene conjugation (+36%, P < 0.05) in the group of 3.0 Gy at 0.5 hours indicated increased lipid peroxidation. At the same time, TBARS were increased (+25%, P < 0.05) in the group of 0.5 Gy, but not in the 3.0-Gy group. In the testis, diene conjugation was not determined at 0.5 hours postirradiation, and at day 1 it was at the control level. The level of TBARS in the testis was below control (-11%, P < 0.01) in the 3.0-Gy group at day 1. At day 31 after 3.0 Gy in the test...
Developmental profiles of the activity of the antioxidant enzymes superoxide dismutase (SOD), cat... more Developmental profiles of the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px), glutathione transferase (GSH-Tr), and hexose monophosphate shunt (HMS) were measured in the rat testis and liver. The level of SOD in the testis was high at the age of 6 to 10 days, after which it dropped to approximately one third of that level by 20 days of age, and remained there up to 8 months of age. In the liver, SOD activity steadily increased from the neonatal to adult stage of life, reaching the same level as detected in the testis. The testicular activity of catalase was only 2% to 7% of that found in liver at all ages. It increased in both organs up to 6 weeks of age, whereafter the hepatic activity gradually decreased and no further changes were seen in the testis. The GSH-Px activity was low in the testis and declined slightly with age, whereas activity in the liver increased four-fold between birth and adulthood. The activity of GSH-T...
Lipid peroxidation products and antioxidant enzyme activities were studied in the rat testis foll... more Lipid peroxidation products and antioxidant enzyme activities were studied in the rat testis followingexposuresto cig- arette smoke, polychlorinated biphenyls (PCB5), or polychlonnated naphthalenes (PCN5). Three hours after a single 1-hour periodof smoke inhalation, the levels of fluorescent chromolipids and thiobar- bituric acid-reactive species (TBARS) were markedly increased in the testis (+49%, P < 0.01, and +43%, P < 0.05, respectively). Twelve hours after daily smoking for 1 hour,for1,5, or 10 days, such an increase was not found. Activities of the antioxidant enzymes superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH- Px), glutathione transferase (GSH-Tr), or hexose monophosphate shunt (HMS) were not affected immediately, 3 hours, or 12 hours after a single smoking session. Twelve hours after smoking for 5 days, the activity of catalase was decreased (-16%, P < 0.05). Smoking exposures had no consistent effects on serum follicle-stim- ulating hormone (...
An experiment was conducted on rats to investigate the capacity of antioxidants to protect agains... more An experiment was conducted on rats to investigate the capacity of antioxidants to protect against acute toxicity caused by D O N or T-2 toxin. Male rats were fed two different feeds. One group received a feed deficient in vitamins C and E and selenium, whereas the other group was fed with a feed enriched in antioxidants. After two weeks, selected groups of rats were administered orally a single dose of D O N or T-2 toxin. After the treatment with mycotoxins, all rats were decapitated. The livers were analyzed for TBARS values, hepatic GSH content and for the activities of CyP-450, CAT, SOD and GSH-TR. Increases in lipid peroxides of 21 YO and 268 % were observed in those rats which did not receive the supplement of antioxidants and which were administered D O N or T-2 toxin, respectively. There was no significant increase in the TBARS values in the groups receiving D O N with selenium and vitamins, but increases of 57 % and 79 % were recorded in the groups administered T-2 toxin and antioxidants. Furthermore, in the groups fed the deficient feed and administered D O N or T-2 toxin, the lipid peroxidation increased by 33 % and 307 %, respectively. N o mortality, and a lower number of intoxicated animals were observed in rats fed a diet supplemented with antioxidants. Significant decrgases of GSH, CAT, SOD, CyP-450 and GSH-TR were recorded in treated rats receiving the deficient feed. The results of this study demonstrate that trichothecenes stimulate lipid peroxidation with consequent decrease of GSH content, but that the dietary use of selenium, a-tocopherol and ascorbic acid provides protection against acute toxicosis caused by D O N or T-2 toxin.
Peroxmomal ~-oxldatlon of fatty acids and the activitms of glutathlonemetabolizing enzymes m rat ... more Peroxmomal ~-oxldatlon of fatty acids and the activitms of glutathlonemetabolizing enzymes m rat liver were measured after administration of 2,4-dichlorophenoxyacetic acid (2,4-D), 4-chloro-2-methylphenoxyacetlc acid (MCPA), cloflbrate [ethyl], 2-(p-chlorophenoxy)-2-methylproplonate], glyphosate (N-phosphonomethyl glycine, a herbmide not structurally related to phenoxy acids) or saline for 14 days. H-Oxidation increased by 6-fold in the group given clofibrate, 3-fold in the 2,4oD-treated group, and 2-fold in the MCPA-treated group over the level in the controls (saline-treated). Glyphosate did not increase H-oxidation. No significant change in reduced glutathione content from that in controls was found in any of the treated groups. Glutathlone reductase activity increased by about 40% after admmlstratlon of either 2,4-D or MCPA, and glutathione peroxldase activity increased by 30 % In animals given MCPA. A slight decrease in glutathyone S-transferase activity was found in the group treated with clofibrate. The marked increases m peroxisomal ~-oxldation of fatty acids were accompamed by only minor changes in the activities of enzymes revolved In glutathmne-dependent Inactivation of organic hydroperoxides and other oxygen-centred reactive agents.
Melanocyte-stimulating hormones, α-, β-and γ-MSH, regulate important physiological functions incl... more Melanocyte-stimulating hormones, α-, β-and γ-MSH, regulate important physiological functions including energy homeostasis, inflammation and sodium metabolism. Previous studies have shown that α-MSH increases sodium excretion and promotes vascular function in rodents, but it is unexplored whether these characteristics of α-MSH could translate into therapeutic benefits in the treatment of hypertension. Therefore, we first assessed the diuretic and natriuretic properties of the stable α-MSH analogue [Nle 4 , D-Phe 7 ]-α-MSH (NDP-α-MSH) and investigated whether it has protective effects in deoxycorticosterone acetate (DOCA)-salt hypertensive mice. Adult male C57Bl/6N mice were subjected to DOCA-salt treatment and randomized to receive intraperitoneal injections of either saline as vehicle or NDP-α-MSH (0.3 mg/kg/day for 14 days) starting 7 days after the DOCA-salt treatment. Systemic hemodynamics, serum and urine electrolytes, and oxidative stress markers were assessed in control sham-operated and DOCA-salt mice. NDP-α-MSH elicited marked diuretic and natriuretic responses that were reversible with the MC3/4 receptor antagonist SHU9119. Chronic NDP-α-MSH treatment attenuated blood pressure elevation in DOCAsalt mice without affecting the blood pressure of normotensive control animals. Owing to the enhanced sodium excretion, NDP-α-MSH-treated mice were protected from DOCA-salt-induced hypernatremia. DOCA-salt treatment mildly increased oxidative stress at the tissue level, but NDP-α-MSH had no significant effects on the oxidative stress markers. In conclusion, treatment with NDP-α-MSH increases urinary sodium excretion and protects against DOCAsalt-induced hypertension. These findings point to the potential future use of α-MSH analogues in the treatment of hypertension.
Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted wit... more Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted with 70% acetone and analyzed for their total phenolics concentration and antioxidant potential. Seven extracts showed more than 85% inhibition of lipid peroxidation in vitro as compared with blank. Butylated hydroxytoluene (BHT) (IC50 = 233.6 microg/l +/- 28.3) was the strongest antioxidant in our test system. The IC50 results indicate that the extracts of Nymphaea lotus L. flowers, Acacia nilotica (Linn.) Delile beans, Terminalia belerica Roxb. fruits, and Terminalia chebula Retz. (fruits, brown) were stronger antioxidants than alpha-tocopherol, while Terminalia chebula Retz. (fruit coat), Terminalia chebula Retz. (fruits, black) and Ricinus communis L. leaves were weaker antioxidant extracts than alpha-tocopherol and BHT. Total phenolics concentration, expressed as gallic acid equivalents, showed close correlation with the antioxidant activity. High performance liquid chromatographic analysis with diode array detection at 280 nm, of the seven extracts indicated the presence of hydroxybenzoic acid derivatives, hydroxycinnamic acid derivatives, flavonol aglycones and their glycosides as main phenolics compounds. This information, based on quick screening methods, enables us to proceed towards more detailed chemical and pharmacological understanding of these plant materials.
Zeitschrift für Naturforschung. C, Journal of biosciences
Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted wit... more Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted with 70% acetone and analyzed for their total phenolics concentration and antioxidant potential. Seven extracts showed more than 85% inhibition of lipid peroxidation in vitro as compared with blank. Butylated hydroxytoluene (BHT) (IC50 = 233.6 microg/l +/- 28.3) was the strongest antioxidant in our test system. The IC50 results indicate that the extracts of Nymphaea lotus L. flowers, Acacia nilotica (Linn.) Delile beans, Terminalia belerica Roxb. fruits, and Terminalia chebula Retz. (fruits, brown) were stronger antioxidants than alpha-tocopherol, while Terminalia chebula Retz. (fruit coat), Terminalia chebula Retz. (fruits, black) and Ricinus communis L. leaves were weaker antioxidant extracts than alpha-tocopherol and BHT. Total phenolics concentration, expressed as gallic acid equivalents, showed close correlation with the antioxidant activity. High performance liquid chromatographic ana...
Oxidized LDL lipids (ox-LDL) are associated with lifestyle diseases such as cardiovascular diseas... more Oxidized LDL lipids (ox-LDL) are associated with lifestyle diseases such as cardiovascular diseases, metabolic syndrome and type 2 diabetes. The present study investigated how postpartum weight retention effects on ox-LDL and serum lipids. The study is a nested comparative research of a cluster-randomized controlled trial, NELLI (lifestyle and counselling during pregnancy). During early pregnancy (8-12 weeks) and 1 year postpartum, 141 women participated in measurements for determining of plasma lipids: total cholesterol (T-C), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), triacylglycerols (TAG) and ox-LDL. Subjects were stratified into tertiles (weight loss, unaltered weight and weight gain groups) based on their weight change from baseline to follow-up. Ox-LDL was determined by baseline level of conjugated dienes in LDL lipids. Among the group of weight gainers, concentration of TAG reduced less (-0.14 vs. -0.33, p = 0.002), HDL-C reduced more (-0.31 vs. -0.16, p = 0.003) and ox-LDL/HDL-C ratio increased (3.0 vs. -0.2, p = 0.003) when compared to group of weight loss. Both T-C and LDL-C elevated more (0.14 vs. -0.21, p = 0.008; 0.31 vs. 0.07, p = 0.015) and TAG and ox-LDL reduced less (-0.33 vs. 0.20, p = 0.033; -3.33 vs. -0.68, p = 0.026) in unaltered weight group compared to weight loss group. The women who gained weight developed higher TAG and ox-LDL/HDL-C ratio as compared to those who lost weight. Postpartum weight retention of 3.4 kg or more is associated with atherogenic lipid profile.
In vivo oxidation of low-density lipoprotein is shown to be significantly related to another risk... more In vivo oxidation of low-density lipoprotein is shown to be significantly related to another risk factor for coronary atherosclerosis, abnormal electrocardiographic late potentials, in clinically healthy pilots. Because both of these variables have been also associated with cardiac arrhythmogenic action, together they may improve the identification of patients at risk of ventricular tachyarrhythmias.
European Journal of Clinical Nutrition, Feb 1, 2008
Objective: To investigate the effects of stanol ester margarine use in healthy subjects on arteri... more Objective: To investigate the effects of stanol ester margarine use in healthy subjects on arterial compliance, endothelial function and intima-media thickness. Design: Case-control study comparing regular stanol ester margarine users to non-users. Setting: Occupational health service clinic. Subjects: We recruited 50 cases and 50 controls (mean age 5178, range 26-65 years). All subjects were non-smokers and the study groups were matched for age and sex. As cases, we invited subjects who had been using regularly (daily) plant stanol ester margarine for a period of 2 years or longer. Non-invasive ultrasound was used to measure carotid artery compliance, carotid intima-media thickness and brachial artery flow-mediated endothelial dependent vasodilatation. Results: The carotid artery compliance was non-significantly higher in cases compared with controls, 1.8471.02 vs 1.5870.76 %/10 mm Hg (P ¼ 0.13). The difference in compliance became statistically significant (P ¼ 0.04) when the unbalance between the groups in family history of coronary artery disease and years of education were taken into account. There was also a significant dose-response relationship between stanol margarine use and carotid compliance, longer use being associated with higher compliance. Serum lipoproteins, blood pressure, flow-mediated dilation and intima-media thickness values did not differ between cases and controls. Conclusion: These data raise the possibility that regular stanol ester margarine use may be associated with beneficial changes in arterial compliance. Intervention studies are needed to test this hypothesis and to reveal possible mechanisms.
Objective-Obesity is associated with endothelial dysfunction that may contribute to the developme... more Objective-Obesity is associated with endothelial dysfunction that may contribute to the development of atherosclerosis.
Oxygen uptake (VO2) on-kinetics is decelerated in acute hypoxia and accelerated in hyperoxia in c... more Oxygen uptake (VO2) on-kinetics is decelerated in acute hypoxia and accelerated in hyperoxia in comparison with normoxia during submaximal exercise. However, the effects of fraction of oxygen in inspired air (FIO2) on VO2 kinetics during maximal exercise are unknown. The effects of FIO2 on VO2 on-kinetics during maximal exercise are similar to submaximal exercise. There were 11 endurance athletes who were studied during maximal 7-min cycle ergometer exercise in hyperoxia (FIO2 0.325), hypoxia (FIO2 0.166) and normoxia (FIO2 0.209). The individual VO2 data were fit to a curve by using a three exponential model. In hypoxia, VO2 on-response amplitude during Phase 2 (approximately 20-100 s from the beginning of exercise) was lower (p < 0.05) when compared with hyperoxia; time constant of VO2 Phase 3 (beyond approximately 100 s after beginning of exercise) was shorter (p < 0.05) when compared with hyperoxia; and mean response time (MRT, O-63%) for VO2peak was shorter (p < 0.05) ...
Research in experimental medicine. Zeitschrift für die gesamte experimentelle Medizin einschliesslich experimenteller Chirurgie, 1999
Nitecapone (NC) has been shown to have beneficial effects on the functional recovery of rat heart... more Nitecapone (NC) has been shown to have beneficial effects on the functional recovery of rat hearts in Langendorff-preparation. The present study was executed to evaluate the effect of NC on preservation of grafts in heart transplantation and the role of NC in the inhibition of granulocyte infiltration. Donor hearts were perfused and stored at +4 degrees C for 8 h in either Ringer solution in the control-group (C-group, n = 26) or in NC (50 microM) added Ringer solution (NC-group, n = 18). The heterotopic heart transplantation was performed. The rats in both groups were killed at either 10 min or 60 min after release of the aortic clamp and tissue samples were obtained for antioxidative capacity, myeloperoxidase activity, and lipid peroxidation measurements. In vitro studies were performed using sodium azide or nitecapone to inhibit myeloperoxidase (MPO) activity of isolated human leukocytes. A total of 61% of the grafts began to beat in the NC-group, compared to 46% in the control g...
The prooxidant effect of X-irradiation on rat testis and liver tissue was studied with doses of 0... more The prooxidant effect of X-irradiation on rat testis and liver tissue was studied with doses of 0.5 and 3.0 Gy; the latter dose kills the proliferating spermatogonia and causes a maturation-depletion process in the germ cells. The level of lipid peroxidation, measured by the formation of diene conjugates and thiobarbituric acid-reactive substances (TBARS) and the activities of the antioxidant enzymes were determined 0.5 hours, 1 day, 7 days, and 31 days after the exposure. In the liver, increased levels of diene conjugation (+36%, P < 0.05) in the group of 3.0 Gy at 0.5 hours indicated increased lipid peroxidation. At the same time, TBARS were increased (+25%, P < 0.05) in the group of 0.5 Gy, but not in the 3.0-Gy group. In the testis, diene conjugation was not determined at 0.5 hours postirradiation, and at day 1 it was at the control level. The level of TBARS in the testis was below control (-11%, P < 0.01) in the 3.0-Gy group at day 1. At day 31 after 3.0 Gy in the test...
Developmental profiles of the activity of the antioxidant enzymes superoxide dismutase (SOD), cat... more Developmental profiles of the activity of the antioxidant enzymes superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px), glutathione transferase (GSH-Tr), and hexose monophosphate shunt (HMS) were measured in the rat testis and liver. The level of SOD in the testis was high at the age of 6 to 10 days, after which it dropped to approximately one third of that level by 20 days of age, and remained there up to 8 months of age. In the liver, SOD activity steadily increased from the neonatal to adult stage of life, reaching the same level as detected in the testis. The testicular activity of catalase was only 2% to 7% of that found in liver at all ages. It increased in both organs up to 6 weeks of age, whereafter the hepatic activity gradually decreased and no further changes were seen in the testis. The GSH-Px activity was low in the testis and declined slightly with age, whereas activity in the liver increased four-fold between birth and adulthood. The activity of GSH-T...
Lipid peroxidation products and antioxidant enzyme activities were studied in the rat testis foll... more Lipid peroxidation products and antioxidant enzyme activities were studied in the rat testis followingexposuresto cig- arette smoke, polychlorinated biphenyls (PCB5), or polychlonnated naphthalenes (PCN5). Three hours after a single 1-hour periodof smoke inhalation, the levels of fluorescent chromolipids and thiobar- bituric acid-reactive species (TBARS) were markedly increased in the testis (+49%, P < 0.01, and +43%, P < 0.05, respectively). Twelve hours after daily smoking for 1 hour,for1,5, or 10 days, such an increase was not found. Activities of the antioxidant enzymes superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH- Px), glutathione transferase (GSH-Tr), or hexose monophosphate shunt (HMS) were not affected immediately, 3 hours, or 12 hours after a single smoking session. Twelve hours after smoking for 5 days, the activity of catalase was decreased (-16%, P < 0.05). Smoking exposures had no consistent effects on serum follicle-stim- ulating hormone (...
An experiment was conducted on rats to investigate the capacity of antioxidants to protect agains... more An experiment was conducted on rats to investigate the capacity of antioxidants to protect against acute toxicity caused by D O N or T-2 toxin. Male rats were fed two different feeds. One group received a feed deficient in vitamins C and E and selenium, whereas the other group was fed with a feed enriched in antioxidants. After two weeks, selected groups of rats were administered orally a single dose of D O N or T-2 toxin. After the treatment with mycotoxins, all rats were decapitated. The livers were analyzed for TBARS values, hepatic GSH content and for the activities of CyP-450, CAT, SOD and GSH-TR. Increases in lipid peroxides of 21 YO and 268 % were observed in those rats which did not receive the supplement of antioxidants and which were administered D O N or T-2 toxin, respectively. There was no significant increase in the TBARS values in the groups receiving D O N with selenium and vitamins, but increases of 57 % and 79 % were recorded in the groups administered T-2 toxin and antioxidants. Furthermore, in the groups fed the deficient feed and administered D O N or T-2 toxin, the lipid peroxidation increased by 33 % and 307 %, respectively. N o mortality, and a lower number of intoxicated animals were observed in rats fed a diet supplemented with antioxidants. Significant decrgases of GSH, CAT, SOD, CyP-450 and GSH-TR were recorded in treated rats receiving the deficient feed. The results of this study demonstrate that trichothecenes stimulate lipid peroxidation with consequent decrease of GSH content, but that the dietary use of selenium, a-tocopherol and ascorbic acid provides protection against acute toxicosis caused by D O N or T-2 toxin.
Peroxmomal ~-oxldatlon of fatty acids and the activitms of glutathlonemetabolizing enzymes m rat ... more Peroxmomal ~-oxldatlon of fatty acids and the activitms of glutathlonemetabolizing enzymes m rat liver were measured after administration of 2,4-dichlorophenoxyacetic acid (2,4-D), 4-chloro-2-methylphenoxyacetlc acid (MCPA), cloflbrate [ethyl], 2-(p-chlorophenoxy)-2-methylproplonate], glyphosate (N-phosphonomethyl glycine, a herbmide not structurally related to phenoxy acids) or saline for 14 days. H-Oxidation increased by 6-fold in the group given clofibrate, 3-fold in the 2,4oD-treated group, and 2-fold in the MCPA-treated group over the level in the controls (saline-treated). Glyphosate did not increase H-oxidation. No significant change in reduced glutathione content from that in controls was found in any of the treated groups. Glutathlone reductase activity increased by about 40% after admmlstratlon of either 2,4-D or MCPA, and glutathione peroxldase activity increased by 30 % In animals given MCPA. A slight decrease in glutathyone S-transferase activity was found in the group treated with clofibrate. The marked increases m peroxisomal ~-oxldation of fatty acids were accompamed by only minor changes in the activities of enzymes revolved In glutathmne-dependent Inactivation of organic hydroperoxides and other oxygen-centred reactive agents.
Melanocyte-stimulating hormones, α-, β-and γ-MSH, regulate important physiological functions incl... more Melanocyte-stimulating hormones, α-, β-and γ-MSH, regulate important physiological functions including energy homeostasis, inflammation and sodium metabolism. Previous studies have shown that α-MSH increases sodium excretion and promotes vascular function in rodents, but it is unexplored whether these characteristics of α-MSH could translate into therapeutic benefits in the treatment of hypertension. Therefore, we first assessed the diuretic and natriuretic properties of the stable α-MSH analogue [Nle 4 , D-Phe 7 ]-α-MSH (NDP-α-MSH) and investigated whether it has protective effects in deoxycorticosterone acetate (DOCA)-salt hypertensive mice. Adult male C57Bl/6N mice were subjected to DOCA-salt treatment and randomized to receive intraperitoneal injections of either saline as vehicle or NDP-α-MSH (0.3 mg/kg/day for 14 days) starting 7 days after the DOCA-salt treatment. Systemic hemodynamics, serum and urine electrolytes, and oxidative stress markers were assessed in control sham-operated and DOCA-salt mice. NDP-α-MSH elicited marked diuretic and natriuretic responses that were reversible with the MC3/4 receptor antagonist SHU9119. Chronic NDP-α-MSH treatment attenuated blood pressure elevation in DOCAsalt mice without affecting the blood pressure of normotensive control animals. Owing to the enhanced sodium excretion, NDP-α-MSH-treated mice were protected from DOCA-salt-induced hypernatremia. DOCA-salt treatment mildly increased oxidative stress at the tissue level, but NDP-α-MSH had no significant effects on the oxidative stress markers. In conclusion, treatment with NDP-α-MSH increases urinary sodium excretion and protects against DOCAsalt-induced hypertension. These findings point to the potential future use of α-MSH analogues in the treatment of hypertension.
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Papers by Markku Ahotupa