Effect of Sub-deficient Zinc Status on Insulin Sensitivity after Burn Injury in Rats

Abstract

Although zinc status is an important parameter in insulin sensitivity, data concerning its implication in noxious burn-induced insulin resistance are scarce. The present study was designed to evaluate the impact of zinc status before burn on the recovery of injury with focus on plasma insulin and glucose levels. The experiment was performed in male adult Wistar rats fed from weaning with a zinc normal diet (80 ppm) or a depleted zinc diet (10 ppm) for 8 weeks and burned to third degree on 20% of their total body surface area. Blood and tissue samples were collected 3, 6, and 24 h after injury in order to study biochemical parameters and the glucose/insulin response in relation with the zinc status. After burn, zinc-depleted rats presented an exacerbated decrease in plasma zinc level. In addition, the burn-induced insulin resistance, leading to protein catabolism, was emphasized, with higher plasma insulin, glucose, and leptin levels in zinc-deficient animals versus normal-fed rats. Our experimental results underlined the interest to early control the zinc status in order to limit the deleterious effects of oxidative stress and insulin resistance in burned patients.

Alcohol Modulation of the Postburn Hepatic Response

“…Zinc is a trace element that is necessary for normal liver function and its deficiency has been associated with both acute and chronic liver disease [186]. Animal studies have shown that zinc deficiency associated with burn injury results in oxidative stress and mitochondrial damage and contributes to the development of insulin resistance [187,188]. Early repletion of zinc in patients with hepatic injury due to burn and alcohol exposure may limit the extent of metabolic disturbance.…”

Enteral Nutrition Support in Burn Care: A Review of Current Recommendations as Instituted in the Ross Tilley Burn Centre

“…This depletion of zinc stores and the resultant decreased serum zinc levels appears to be uncorrelated with the size of the burn injury [35]. Within rat models zinc depletion elicited greater levels of burn induced insulin resistance with associated protein catabolism and hyperglycemia than that seen in rats with normal zinc levels [36]. Studies examining the critical care population have found an inverse relationship between serum zinc levels and Sequential Organ Failure Assessment scores [37].…”

Review of Burn Injury Research for the Year 2009

“…Zinc levels after burn injury seem to have an impact on the metabolic response to injury and the burn-injury stress response. 49 Burn hypermetabolism has been well described; however, the function of the intestine has had less study. One article examined the intestinal dipeptide absorption function after burn injury in a 30% TBSA rat burn injury model.…”