Zinc deficiency and a high-fat diet during growth: Metabolic and adipocyte alterations in rats

Abstract

Background and aims: To evaluate the effects of a high-fat diet during post-weaning growthon intermediate metabolism and retroperitoneal adipose tissue, in adult male rats exposed toadequate or deficient zinc intake during prenatal and postnatal life.Methods and results: Female Wistar rats were fed low- or control-zinc diets from pregnancyto offspring weaning. Male offspring born from control mothers were fed either control orhigh-fat, control-zinc diets for 60 days. Male offspring born from zinc deficient mothers werefed either low-zinc or high-fat, low-zinc diets for 60 days. At 74 days of life, oral glucosetolerance test was performed. In 81-day-old offspring, blood pressure, lipid profile, plasmaticlipid peroxidation and serum adiponectin level were determined. In retroperitoneal adiposetissue, we evaluated oxidative stress, morphology and adipocytokines mRNA expression.Low-zinc diet induced adipocytes hypertrophy, increased oxidative stress, and decreasedadiponectin mRNA expression in adipose tissue. Low-zinc diet increased systolic bloodpressure, triglyceridemia, plasmatic lipid peroxidation and glycemia at 3 hours after glucoseoverload. Animals fed high-fat or high-fat, low-zinc diets showed adipocytes hypertrophy,decreased adiponectin mRNA expression, and increased leptin mRNA expression andoxidative stress in adipose tissue. They also exhibited decreased serum adiponectin levels,increased triglyceridemia, plasmatic lipid peroxidation and area under the oral glucosetolerance curve. High-fat, low-zinc diet induced greater alterations in adipocyte hypertrophy,leptin mRNA expression and glucose tolerance test than high-fat diet.Conclusion: Zinc deficiency since early stages of intrauterine life could increasesusceptibility to metabolic alterations induced by high-fat diets during postnatal life.