The influence of sub‐optimal protein nutrition on insulin hypersecretion evoked by high‐energy/high‐fat feeding in rats

Abstract

Low (8%) protein feeding during pregnancy impairs the functional development of the fetal endocrine pancreas. ('ontinued low-protein feeding post-nataHy decreases pancreatic insulin content and secretion, whereas transfer to standard diet evoked ~-cell recuperation. Glncose-stimulated insulin secretion (GSIS) and insulin action were examined in vivo at 28 days after transfer from 8% protein diet to a high-energy/high-fat/standard (20%)-protein diet (HEF diet). HEF feeding dramatically enhanced GSIS after intravenous glucose in control rats, but not in rats previously maintained on the low-protein diet. ltowever, glucose disappearance after intravenous glucose, and glucose production and whole-body glucose disposal during euglycaemic-hyperinsulinaemic clamps were unaffected by prior protein malnutrition. In conclusion, impaired insulin secretion after protein malnutrition is exacerbated by high-energy/high-fat |eeding, but this response is not linked to enhanced whole-body insulin resistance.

The Composition of Dietary Fat Directly Influences Glucose-Stimulated Insulin Secretion in Rats

“…The total and saturated fat content of our Lard diet lies at the upper end of the typical fat intake for people in the U.S. (32)(33)(34), whereas the fat intake in the Surwit diet exceeds that normally consumed by humans and may elicit greater lipotoxicity within the ␤-cell. More importantly, the diets in the current study, and that reported by Holness and Sugden (28,30), provide significant amounts of carbohydrates in the form of complex carbohydrates, whereas the diabetogenic Surwit diet contains only the simple sugars maltose and sucrose. Therefore, it is quite likely that an interaction with the carbohydrate component of the diet modifies the impact of fat intake on GSIS.…”

“…In particular, Holness and Sugden (28,30) showed that the provision of rats with dietary saturated fat significantly enhanced insulin secretion during an intravenous glucose challenge. Ahren et al (31) examined responses in rats receiving a diet supplemented with 58% of calories from lard.…”

Age-dependent impact of zygosity and birth weight on insulin secretion and insulin action in twins

“…Metabolic studies among humans and in particular among rodents have shown permanent changes in the structure and/or function of involved organs after exposure to an adverse intrauterine environment during critical stages of foetal development leading to the development of two major metabolic abnormalities responsible for the development of overt Type II diabetes i.e. impaired insulin secretion [7,8,9,10,11,12] and insulin resistance [13,14,15,16,17,18,19]. However, most human studies have used indirect techniques to measure insulin action including hyperinsulinaemia, HOMA or insulin sensitivity index (MINMOD) [13,14,15,18], and several studies have failed to show Several epidemiological studies have indicated an influence of the intrauterine environment and in particular of low birth weight for the development of Type II (non-insulin-dependent) diabetes mellitus later in life [1][2][3][4][5].…”

Influences of pre- and postnatal nutritional exposures on vascular/endocrine systems in animals.

“…However, these offspring undergo a greater age-dependent loss of glucose tolerance compared to controls such that by 15 months of age these animals have a significantly worse glucose tolerance than controls (9). There are also data to suggest that this deterioration can be accelerated by the provision of a high-fat diet (19 (12). These changes appeared to be associated with an increased hepatic glucose output (20).…”

“…Interestingly, the growth of the spontaneously hypertensive rat (SHR) is reduced at days [16][17][18][19][20] but is normal at birth. Growth retardation is associated with a placenta larger than normal (58).…”