histological and immunohistochemical study on the possible protective effect of omega-3 polyunsaturated fatty acids on isoprenaline induced myocardial fibrosis in rats

Preclinical and clinical studies have demonstrated that omega-3-polyunsaturated fatty acids [omega-3-PUFAs] play a significant role in the prevention of cardiovascular diseases. This study aimed to investigate the possible protective effect of omega-3-PUFAs on isoprenaline [ISP]-induced myocardial fibrosis. Thirty-two adult male albino rats were divided into five groups. Group I represented the control group [eight rats]. In group II, six rats were given omega-3-PUFAs [40 mg/kg/day] orally for 8 weeks. In group III, six rats were injected subcutaneously with ISP [5 mg/kg/day] for 4 consecutive days and sacrificed 2 days later. In group IV, six rats were injected with ISP [5 mg/kg/day] for 4 consecutive days and sacrificed after 2 weeks. In group V, six rats were given omega-3-PUFAs [40 mg/kg/day] for 8 weeks, following which they were injected with ISP [5 mg/kg/day] for 4 consecutive days, and sacrificed 2 days later. Serum creatine phosphokinase-MB [CPK-MB] was measured. Myocardial sections were subjected to H and E, Masson's trichrome stain, and alpha-smooth muscle actin [alpha-SMA] immunohistochemical stain. Group II showed nonsignificant difference in the mean CPK-MB level compared with the control. Myocardial sections revealed a histological architecture similar to that of the control. The mean area% of collagen and alpha-SMA immunoreactivity was nonsignificant when compared with the control. Group III showed significant increase in mean CPK-MB compared with the control. Myocardial sections showed disorganization, inflammation, exudation, and fibrosis with significant increase in the mean area% of collagen and alpha-SMA immunoreactivity compared with the control. Group IV showed significant increase in mean CPK-MB, area% of collagen, and alpha-SMA immunoreactivity compared with the control, with progression in the myocardial histological alterations. Group V showed significant decrease in the mean CPK-MB with decrease in histological changes, and there was significant decrease in the mean area% of collagen and alpha-SMA immunoreactivity compared with the ISP groups. omega-3-PUFAs exert cardioprotective effects against ISP-induced myocardial fibrosis

Histological and immunohistochemical study on the adverse effects of sodium chlorate on the pituitary-thyroid axis of albino rats and the possible protective effect of curcumin

Background: Sodium chlorate [NaClO[3]] is found in drinking water, but it has a toxic effect on thyroid. However, curcumin has a thyroid-stimulating effect

Aim of the work: To study the effect of NaClO[3] on the pituitary-thyroid axis of rats and determine the possible protective role of curcumin

Materials and methods: Thirty rats were divided into three groups of 10 rats each. Group I was the control group. In group II, rats received 0.2 g/l of NaClO[3] in drinking water for 3 weeks. In group III, rats received curcumin [100 mg/kg] 1 week before exposure to NaClO[3] and it was continued for 3 weeks. T3, T4, thyroid-stimulating hormone, and superoxide anion were measured. Sections were subjected to H and E, azan stain, caspase-3, and S-100 immunohistochemical stains

Results: In group II, serum T3 and T4 were significantly decreased whereas thyroid-stimulating hormone and superoxide anion were significantly increased compared with the control group. The thyroid gland showed follicular cell hypertrophy, hyperplasia, decreased colloid, and significantly decreased caspase-3 immunoreactivity compared with the control group. The pituitary gland showed significantly increased basophils and significantly decreased S-100-positive folliculostellate cells compared with the control group. In group III, thyroid function tests were significantly improved compared with group II, but did not reach the control level. Thyroid sections appeared apparently normal, with significantly increased caspase-3 immunoreactivity compared with the control group and group II. The pituitary gland showed basophils that were similar to those of the control group. S-100-positive folliculostellate cells were significantly increased compared with group II, but did not reach the control level

Conclusion: Curcumin can protect the thyroid gland from the adverse effects of NaClO[3] and consequently protects the pituitary gland from negative feedback