Effect of aluminium on lipid profile and atherogenic index in prepubertal and young adult female rats: A pilot study

Objectives: Exposure of aluminium (Al) to mankind is inescapable, and its dyslipidaemic impact is a possible contributing factor to health hazards like cardiovascular diseases. The health effects due to the metalloestrogenic property of the metal need imperative consideration. The current experimental work was undertaken to explore Al-induced dyslipidaemia due to its metalloestrogenic property. Materials and Methods: To fulfil this objective, prepubertal (PP) and young adult (YA) female Wistar rats were intraperitoneally administered to two doses of Al [5 and 10 mg/Kg body weight (BW)] once daily for 2 weeks. After the completion of the acute exposure protocol, plasma and hepatic tissue lipid profiles were estimated. Analysis of variance was carried out by the Kruskal–Wallis test and the differences between the groups were analysed by Mann–Whitney U post hoc test Results: Increased triglyceride, total cholesterol, low-density lipoprotein (LDL) cholesterol and very-LDL cholesterol in plasma were found in YAs treated with both doses of Al in a dose-dependent manner. Similar changes were not present in PP female rats. Decreased levels of lipid levels were observed in the case of hepatic lipid profile. Conclusion: The study ushers light towards the dyslipidaemic alterations in experimental female rats after acute Al exposure. Impacts of Al on the growth and organosomatic index during the vital developmental days were significantly decided by the pubertal status of the female rats. The results of this study indicate the impact of puberty on the Al-induced modifications in lipid profile parameters and cardiovascular risk factors.

Curative effect of methionine on certain enzymes of chick kidney cortex under lanthanum toxicity situation.

Acute single dose administration of lanthanum chloride (250 mg/kg body wt, ip) to chicks have been found to alter the levels of enzymes of the antioxidant defence system of chick renal cortex fractions. Such changes involved significant decrease in activities of glucose-6-phosphate dehydrogenase, glutathione reductase, glutathione peroxidase and catalase of kidney epithelial cells. However glutathione-S-transferase activity was not altered. Glutathione and total thiol contents were decreased while lipoperoxidative reactions in kidney-cortex was significantly enhanced. The data indicate that amelioration of lanthanum toxicity condition by methionine supplementation may be due to the methionine serving as a precursor of glutathione.

Impact of chromium on lipoperoxidative processes and subsequent operation of the glutathione cycle in rat renal system.

Oral administration of K2Cr2O7 to male albino rats at an acute dose of 1500 mg/kg body wt/day for 3 days brought about sharp decrease in the activities of glucose-6-phosphate dehydrogenase and glutathione reductase of kidney epithelial cells. The scavenging system of kidney epithelium is also affected as evident by the highly significant fall in the activities of glutathione peroxidase, superoxide dismutase and catalase which ultimately leads to the increase in lipid peroxidation value in kidney cortical homogenate. However, glutathione-s-transferase activity in cytosol and glutathione and total thiol content in cortical homogenate were not altered. Chronic oral administration of K2Cr2O7 (300 mg/kg body wt/day) for 30 days to rats lead to elevation in the activities of glutathione peroxidase, glutathione reductase, glutathione-s-transferase, superoxide dismutase and catalase with no change in glucose-6-phosphate dehydrogenase activity in epithelial cells. This might lead to the increase in glutathione and total thiol status and decrease in lipid peroxidation value in whole homogenate system.

Effect of chromium administration on glutathione cycle of rat intestinal epithelial cells.

Acute oral administration of K2Cr2O7 (1500 mg/kg body wt/day) for 3 days to rats led to the decrease in activities of glucose-6-phosphate dehydrogenase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, superoxide dismutase and catalase of intestinal epithelial cells. Glutathione and total thiol contents were decreased while lipid peroxidation was increased markedly using the whole homogenate of the intestinal epithelial cells. Chronic oral administration of K2Cr2O7 (300 mg/kg body wt/day) for 30 days to rats on the other hand, led to marked increase in superoxide dismutase and glutathione peroxidase activities with no appreciable change in glucose-6-phosphate dehydrogenase, glutathione reductase and catalase activities. However, glutathione-S-transferase activity was decreased significantly. In the whole homogenate of rat intestine, glutathione and total thiol contents were decreased not so significantly but there was a slight enhancement in lipid peroxidation value.

Age-related changes of glycogen metabolism in human fetal heart.

The changes in the activities of three important glycogen metabolising enzymes, viz. glycogen synthetase, glycogen phosphorylase and alpha-D-glucosidase, along with glycogen content have been measured in adult human heart and human fetal heart collected at 13-36 weeks of gestation. At an early period, particularly 13-16 weeks of gestational age, the activity of glycogen synthetase and glycogen content were found to be maximum. However the activity of glycogen phosphorylase remained constant throughout the gestation and that of alpha-D-glucosidase showed a peak at 25-28 weeks of gestation, thereby indicating that fetal heart tissue has the capacity to utilise glycogen for energy.

Biochemical studies on the in vitro effect of doxepin on Mg2+ & Na+, K+)-ATPases of human foetal & adult brain.

The in vitro effect of doxepin at 10, 50 and 200 micrograms/mg protein on Mg2+ and (Na+ K+)-ATPases (EC 3.6.1.3) activities of human foetal and adult brain (crude homogenate of cerebrum and cerebellum) were studied at 10-30 wk of gestation. Both Mg2+ and (Na+, K+)-ATPases of human foetal and adult brain were found to be inhibited by doxepin in a dose dependent manner. The inhibitory effect neither varied with respect to the region (i.e., cerebrum and cerebellum) nor with the gestational ages. Inhibition of ATPases activity by doxepin may affect the release and uptake of biogenic amines in the CNS, which may hamper the maturation of brain.

In vitro effect of lorazepam on Mg2+ and (Na+,K+) ATPases of human foetal brain.

Lorazepam (LZ), a benzodiazepine group of drug, inhibits Mg2+ and (Na+,K+) ATPases (EC 3.6.1.3) activity of human foetal and adult brain. The inhibitory effect neither varied with respect to the region (i.e. cerebrum and cerebellum) nor with the age of the foetus. The inhibition of ATPases activity indicates that the neuronal transmission processes, may be affected and raises the possibility of developmental disturbances.

Glycogen metabolism in human fetal testes.

The ontogeny of glycogen synthetase, glycogen Phosphorylase and α-Dglucosidase, enzymes which are associated with glycogen metabolism and glycogen level has been studied in human fetal testes of gestational age ranging from 14-32 weeks. Glycogen synthetase activity reaches the peak value at 17-20 weeks of gestation, thereafter it decreases. α-D-Glucosidase activity increases with the advancement of pregnancy up to 28 weeks of gestation decreasing thereafter very rapidly. Phosphorylase activity remains more or less constant throughout gestation. The maximum increase in glycogen content at early stages of gestation (17-20 weeks) and gradual reduction with the advancement of pregnancy are correlated with histochemical observation by the periodic acid-Schiff technique.