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Документ Age-related changes of glycolytic activity and antioxidant capacity in the blood of alloxan diabetic rats(Полтавський державний медичний університет, 2020) Kushnir, O. Yu.; Yaremii, I. M.; Кушнір, О. Ю.; Яремій, І. М.; Кушнир, А. Ю.; Яремий, И. М.The increasing incidence of type 1 diabetes coupled with advances in treatment of type 1 diabetes has resulted in an unprecedented number of older adults living with and controllable type 1 diabetes. The objective of this experimental study was to assess the impact of aging on the level of basal glycaemia and activities of glucose-6-phosphate dehydrogenase [EC1.1.1.49], pyruvate kinase [EC 2.7.1.40] and glutathione reductase [EC1.6.4.2] in erythrocytes of alloxan-diabetic rats. Methods: We used 100 male Wistar rats, divided into two age groups: I group included- 2-month (adult) animals, and II group was made up of 4-month (old) animals. Diabetes was modelled by injecting the rats with 5% solution of alloxan monohydrate intraperitoneally in a dose of 170 mg/kg. Blood was taken from the tail vein to evaluate the basal glycaemia on 5-th and 47-th day after the alloxan injection. Rats were sacrificed on the 47-th day of the experiment in accordance with the regulations on ethical treatment of vertebrates. The assessment of the activity of the enzymes was carried out by standard methods. Statistical analysis was performed by using Statistica 10 StatSoft Inc. Results. The level of basal glycaemia on the fifth day of the experiment in the animals of both groups went up on average by 115% from baseline values. We founded that on 47-th day this index was higher in group of old rats by 20% than in adult rats. Pyruvate kinase activity in erythrocytes of adult and old animals with diabetes decreased by 35% and 50% respectively compared with the control. Glucose-6-phosphate dehydrogenase activity in erythrocytes of adult and old animals with diabetes decreased by 27% and 45% respectively compared with the control on 47-th day. The changes may be considered as the result of age-related disorders of glucose metabolism due to disturbances in free radical mechanisms. Glutathione reductase activity in erythrocytes of adult and old animals with diabetes decreased by 29% and 35% respectively compared with the control on 47-th day. Conclusion. We have determined when getting aged, the alloxan-diabetic rats demonstrate changes in the sensitivity of pyruvate kinase, glucose-6-phosphate dehydrogenase and glutathione reductase activities in erythrocytes resulted from the effect of diabetes mellitus factors (hyperglycaemia). We can suggest that glycaemic control is key purpose for older patients with type 1 diabetes in order to prevent of complication, which can be aggravated with age.Документ Influence of melatonin on age-related changes of carbohydrate metabolism and antioxidant capacity in the blood of alloxan diabetic rats(Полтавський державний медичний університет, 2021) Yaremii, I. M.; Kushnir, O. Yu.; Яремій, І. М.; Кушнір, А. Ю.Melatonin and its metabolites have potent antioxidant/anti-inflammatory properties, and they have proven to be highly effective in a variety of disorders linked to inflammation and oxidative stress. The object of this experimental research was to ascertain the influence of aging on the level of basal glycemia and activities of glucose-6-phosphate dehydrogenase [EC1.1.1.49], pyruvate kinase [EC 2.7.1.40] and glutathione reductase [EC1.6.4.2] in erythrocytes of alloxan diabetic rats on the background of melatonin injections. Methods: We used 100 male Wistar rats, two age groups: the - 2-month (adult), and II - 4-month (old). Alloxan diabetes was evoked via injecting the rats with a 5% solution of alloxan monohydrate intraperitoneally in a dose of 170 mg/kg. Four days after diabetes induction, rats were divided into diabetic (untreated) and melatonin-diabetic group (10 mg/kg, daily and intraperitoneally for six weeks). Blood was taken from the tail vein evaluate the basal glycemia on 5-th and 47-th day after the injection of alloxan. Rats were sacrificed at the 47-th day of the experiment accordance with the ethical treatment of animals. Determinations of the enzymes activities were by standard methods. Statistical analysis was performed using Statistica 10 StatSoft Inc. Results. The level of basal glycemia on the fifth day of the experiment in animals of both groups increased on average by 115% from baseline values. We founded that on 47-th day this index was higher in group of old rats on 20% more than in adult rats. Pyruvate kinase activity in erythrocytes of adult and old animals with diabetes decreased by 34% and 51% respectively compared with the control. glucose-6-phosphate dehydrogenase activity in erythrocytes of adult and old animals with diabetes decreased by 25% and 44% respectively compared with the control on 47-th day. The changes may be the result of age-related disorders of glucose metabolism due to disturbances in free radical mechanisms. Glutathione reductase activity in erythrocytes of adult and old animals with diabetes decreased by 30% and 36% respectively compared with the control on 47-th day. A 42-days injection of melatonin to the alloxan diabetic rats of both groups contributed to a normalization of the level of basal glycemia, the activities of pyruvate kinase and glutathione reductase in the rat blood, as well as to a considerable increase of the activity of glucose-6-phosphate dehydrogenase, whose level exceeded by average 9% this particular index in the control group of animals. Under the influence of melatonin increase activity of glucose-6-phosphate dehydrogenase in the blood of rats may be due to the increasing number of substrate for glucose-6-phosphate dehydrogenase (stimulating the flow of glucose into cells and its phosphorylation) and direct action. Conclusion. In this case melatonin probably increases use of glucose for regeneration of NADPH2 and aerobic oxidation of glucose that indicate an acceleration of antioxidative protection and energy production in blood of adult and old diabetic rats.Документ Melatonin improves mitochondrial function and decreases oxidative stress in gums of diabetic rats(Українська медична стоматологічна академія, 2018) Yaremii, I. M.; Kushnir, O. Yu.; Khlus, K. M.; Яремий, И. М.; Кушнир, А. Ю.; Хлус, К. М.; Яремій, І. М.; Кушнір, О. Ю.; Хлус, К. М.It is known that melatonin not only carries out control of circadian and seasonal biorhythms in the human body, but also helps to maintain oxidative antioxidant homeostasis and normoglucemia in the body. The purpose of the study was to determine the effect of melatonin on the content of reduced glutathione and the activities of glutathione peroxidase, catalase and superoxide dismutase, as well as the content of TBC reactive compounds and protein carbonyl content in the cytosol, and the activities of succinate dehydrogenase and H+-ATP-ase in the mitochondria of the gums of rats with alloxan diabetes mellitus. Research methods. Animals were divided into 5 groups: 1) control; 2) rats with apparent diabetes – basal glycemia levels ≥ 8.0 mmol / l; 3) rats with apparent diabetes who, from day 5 after administration of aloxane, received daily melatonin 10 mg / kg of weight during 7 days daily at 8:00 per os; 4) rat with impaired glucose tolerance - basal glycemia level ≤ 6.9 mmol / l; 3) rats with impaired glucose tolerance, which were similarly administered within 7 days of melatonin. Results and discussion. In gingival tissues of rats with apparent diabetes, reduction in the content of reduced glutathione by 30% and increased activity of glutathione peroxidase by 32% were observed, respectively, when compared with control rats. The activity of catalase and superoxide dismutase decreased by 18% and 46% in the group of diabetic rats than in the control group. In the group of animals with impaired glucose tolerance, the activity of catalase was 25% higher than control. The content of TBC reactive compounds increased in groups of diabetic rats and with impaired glucose tolerance by 65% and 36% respectively, while the level of oxidized proteins in animals with diabetes increased by 52% compared to control. In the mitochondrial fraction of gum cells, decrease in the activity of succinate dehydrogenase and H + -ATPase in animals with diabetes was found to be 68% and 41%, respectively, as compared to control. Weekly daily administration to rats with apparent diabetes melatonin at a rate of 10 mg / kg contributed to the normalization of the glutathione system and basal glycemia we studied. Conclusion: These results demonstrate that melatonin supplementation prevents gingival mitochondrial dysfunction induced by diabetes in association with decreased oxidative stress.Документ The effect of melatonin on the energy me tabolism in heart of diabetic rats(Українська медична стоматологічна академія, 2019) Kushnir, O. Yu.; Yaremii, I. M.; Кушнир, А. Ю.; Яремий, И. М.; Кушнір, О. Ю.; Яремій, І. М.The aim of this study was to determine the effect of melatonin on activity of pyruvate kinase (PK) and lactate dehydrogenase (LDH) in the heart tissue and on the activity of succinate dehydrogenase (SDG) and H+ATPase in mitochondria of cardiomyocytes of rats with dexamethasone diabetes. Methods. The research was performed in compliance with the Rules of the work with test animals (1977) and the European Convention on the Protection of Vertebrate Animals used in experiments and other scientific purposes (18 March 1986). The experiments were carried out on 36 sexually mature male albino rats with the body mass 0.18 – 0.20 kg. The animals were divided into 3 groups:1) control group; 2) group with diabetes mellitus DM (BG level ≥ 8.0 mmol/l); 3) diabetic animals which were injected with melatonin. Melatonin (“Sigma”, USA) was injected intraperitoneally in a dose of 10 mg/kg of body weight daily over 13 days. Dexamethasone diabetes was evoked by daily subcutaneous administration of dexamethasone (solution for injection 4 mg / ml, KRKA, Slovenia) at a dose of 0.125 mg / kg body weight for 13 days (O.V. Stefanov, 2001). The mathematical model of the insulin-glucose correlation by the Homeostasis Model Assessment (HOMA) was used to evaluate the insulin resistance in the animals (D.R.Matthews et al., 1985). The blood was taken from the tail vein to evaluate the BG level using “OneTouchUltra” (“LifeScan”, USA). The rats were sacrificed on the 14th day of the experiments in accordance with the ethical treatment of animals. 5% homogenate was prepared from cold-isolated rat hearts on chilled 50 mM Tris-HCl buffer (pH = 7.4) with sucrose. Mitochondria were isolated by differential centrifugation. Enzyme activities in the mitochondrial fraction was determined by: succinate dehydrogenase (SDG) according to the method of Eshchenko N.D. et al. (1992), H + -ATP-ase - for Gabibiv M.M. (1986). Serum insulin content was determined using an automatic immunochemiluminescent analyzer (Snibe Co., Ltd, PRC) using a Maglumi test kit. The insulin resistance index (HOMA-IR) was calculated by the formula: HOMA-IR = (glucose (mmol / l) • insulin (mcU / ml)) / 22.5. To determine the enzymes activities by standart methods, heart muscle tissue was quickly removed, rinsed in saline, blotted, weighed and homogenized. Then the homogenate (5% in ice-cold 0.25 mM tris-HCl-buffer) was ultracentrifugated (10 min at 1500r/min) and the supernatant was used for measurements. Statistical analysis was performed using Statistica 10 (StatSoft Inc). Prior to analysis, Shapiro-Wilk test was used to assess the normality of the group data. According to the criterion, the samples distributions differed from normal distribution. Given these, use of the Mann-Whitney test was considered sufficient for valid conclusions to be made. Differences were considered to be statistically significant when P ≤ 0.05. Results. In the blood of all diabetic rats on the 14th day the glucose content exceeded 8.9 mmol / l, and the HOMA-IR index increased 7 times. According to results, we have obtained the activity of PK in the heart tissue of diabetic animals was 55% less than in control group. It can be explained by low uptake of glucose from the blood by heart muscle tissue in conditions of insulin resistance. Reduced glucose uptake by peripheral tissues, in turn, leads to a reduced rate of glucose metabolism. That means now substrate for next catabolic changes in glycolysis. The activity of LDH increases by 32% in the heart muscles of diabetic rats compared with the control values. We have found out that the activity of PK and LDH has become normalized by the introducing of melatonin in dose of 10 mg/kg of body weight. In the mitochondria of the animals with dexamethasone diabetes, the activity of SDG and H+ -ATPase is significantly lower than that in intact animals by 45 and 32%, respectively. Probably, melatonin enhances the uptake of glucose by heart muscles. The blood glucose content of diabetic rats, which were administered is not significantly different from that of the intact animals, and the HOMA-IR was 6.3 times lower than that of diabetic rats. The activity of SDG and H+-ATPase in the mitochondria of rats receiving both melatonin and dexamethasone does not differ from that of intact rats. Conclusion. A 14-day introduction of melatonin leads to a marked improvement of the state of carbohydrate metabolism as well as the energy metabolism in heart tissue that is accompanied by the normalization of the indices studied.