Long-chainn-3 PUFA given before and throughout gestation and lactation in rats prevent high-fat diet-induced insulin resistance in male offspring in a tissue-specific manner

Abstract

This study investigated whether long chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs) given to pregnant rats fed a high fat (HF) diet may prevent fetal programming in male offspring at adulthood. Six weeks before mating, and throughout gestation and lactation, female nulliparous Sprague-Dawley rats were given a chow (C) diet, HF (60.6% fat from corn, rapeseed oils and lard) or HF in which one third of fat was replaced by fish oil (HF n-3). At weaning, the 3 offspring groups were randomly separated in 2 groups fed C diet, or HF without LC n-3 PUFAs, for 7 weeks until adulthood. Glucose tolerance and insulin sensitivity were assessed by an oral glucose tolerance test both at weaning and at adulthood. Insulin signaling was determined in liver, muscle and adipose tissue by quantification of the phosphorylation of Akt on Ser 473 at adulthood. At weaning, as at adulthood, offspring from HF-fed dams were obese, and displayed glucose intolerance (GI) and insulin-resistance (IR), but not those from HFn-3 fed dams. Following the post-weaning C diet, phosphorylation of Akt was strongly reduced in all tissues of offspring from HF dams, but to a lesser extent in liver and muscle of offspring from HFn-3 dams. However, it was abolished in all tissues of all offspring groups fed the HF post-weaning diet. Thus, LC n-3 PUFAs introduced in a HF in dams, partially prevented the transmission of GI and IR in adult offspring even though they were fed without LC n-3 PUFAs from weaning.

Fish oil minimises feed intake and improves insulin sensitivity in Zucker fa/fa rats

“…The present study was designed to evaluate whether a low dose of LC n-3 PUFA given as FO could prevent the genetic predisposition of ZO rats to develop IR, as they do in several other models of nutritionally induced IR in rodents (3)(4)(5)(6) . As awaited, in response to an OGTT, ZO rats displayed, in response to an OGTT, a higher AUC glycaemia and insulinaemia than ZL rats, which translates both glucose intolerance and IR.…”

“…Similarly, in humans, they also prevent or even decrease IR. Furthermore, when given before and throughout gestation and lactation in dams fed a high-fat diet, they can hamper materno-fetal-transmitted IR in male offspring (6) . However, in rats made insulin resistant by a glucocorticoid (dexamethasone), they amplify the decrease in liver and muscle PI3K activity, resulting in an increase in the dexamethasone-induced alteration of insulin signalling (7) .…”

High dietary intake of unsaturated fatty acids is associated with improved insulin resistance – a cross-sectional study based on the NHANES database

“…UFA is an important component of body fat and include monounsaturated and polyunsaturated fatty acids that are derived from foods such as vegetables, fruits, nuts, and fish. In vitro [ 1 , 2 ] and in vivo [ 3 , 4 ] studies have shown that UFA improve insulin sensitivity by regulating metabolic-related cellular pathways. Several cohort studies [ 5 – 7 ] have also reported that a moderate intake of UFA improves insulin resistance.…”