Modulation of Zn‐induced hyperinsulinemia/insulin resistance in Wistar rat fed modified poultry egg^Ψ

Abstract

Excessive bioavailability of Zn causes Cu and Mg deficiencies resulting in hyperglycemia and hyperinsulinemia/insulin resistance. These defects may ameliorate if the ionic imbalance in them is corrected. In view of this, three groups of rats were included in this study. Initially, they were fed on semi-synthetic equicalories basal diet containing 20 mg Zn (control, group-I), on 40 mg Zn (group-II) and 80 mg Zn/kg diet (group-III) respectively for 3 months. Thereafter, half of the rats in group-II and III were shifted on Cu and Mg enriched modified poultry egg (ME(Psi)) mixed diets (groups-IIME and IIIME) while the remaining were continued to feed on their respective diets for another 3 months completing a total of 6 months. Hyperglycemia, hyperinsulinemia, hypercortisolemia, hyperzincemia, hypercupremia and hypermagnesaemia with corresponding increase of lipid droplets in the zona fasciculate of adrenal cortex and reduction in liver glycogen content in rats of groups-II and III were recorded. These changes were linked with a rise in Zn and fall in Cu and Mg in their liver. The addition of ME(Psi) in their diets led to fall of Zn and rise in liver Cu and Mg, and fall in serum Zn, Cu and Mg resulting in the improvement of glucose disposal, increase in insulin sensitivity, reduction in lipid droplets in zona fasciculate and increase in glycogen content in the liver approaching closer to the control group-I. The data suggest that these ME(Psi) can serve as non-pharmacological dietary supplement to prevent insulin resistance/hyperinsulinemia in populations who are at higher risk of diabetes mellitus either due to their genetic predisposition of excessive absorption and retention of Zn or due to higher Zn content in the food chain.

Whole Egg Consumption Prevents Diminished Serum 25-Hydroxycholecalciferol Concentrations in Type 2 Diabetic Rats

“…Similarly, others have found diets containing whole eggs exhibit a positive impact on glucose tolerance and insulin sensitivity. 9,22 Here, we demonstrated that whole egg consumption resulted in approximately a 50 percent reduction in hyperglycemia. A likely explanation for this could be a diet effect on body weight, with respect to the relationship between obesity and impaired glucose homeostasis.…”

Trace elements in glucometabolic disorders: an update

“…Zn restriction increased oxidative stress and the levels of isoprostanes [100], in line with antioxidant effects of Zn. Excessive Zn, on the other hand, increased metabolic syndrome in rats fed a high fat/sucrose diet [101]; this could be reversed by copper and magnesium-enriched poultry egg [102]. …”

Attenuation of Zn-induced hyperleptinemia/leptin resistance in Wistar rat after feeding modified poultry egg

“…Once ceruloplasmin is synthesized, it is transported into the blood resulting in a reduction of Cu in tissues with concomitant increase in serum Cu and stimulated increase of metallothionein elevates Zn concentration in tissues. This leads to the imbalance of Cu and Zn concentrations in the serum and different tissues [17]. The deficiency of Cu in soft tissues have been shown to decrease Cu-metalloenzymes notably Zn-Cu superoxide dismutase, catalase and selinoglutathione peroxidase which form active component of antioxidant defense system [50,51].…”

“…The CEs were obtained from the Bee jee poultry farm, Panchkula, India. They were analyzed for cholesterol [25,26], triglycerides [27], total lipids [28], proteins [29], carbohydrates [30,31], vitamin E [32,33], linolenic acid and minerals (Zn, Cu and Mg) as described previously [17]. …”

“…253740). The severity of physiological disorders due to oxidative stress caused by excessive Zn decreased significantly on feeding these modified poultry egg (ME) mixed diets by restoring the minerals levels in blood serum and tissues as reported in the previous study [17]. Therefore, the present work was undertaken to study the effect of ME verses conventional egg (CE) on Zn induced hyperleptinemia [14] and results are reported in this paper.…”