Soybean oil treatment impairs glucose-stimulated insulin secretion and changes fatty acid composition of normal and diabetic islets

Abstract

We investigated the effect of sub-chronic soybean oil (SO) treatment on the insulin secretion and fatty acid composition of islets of Langerhans obtained from Goto-Kakizaki (GK), a model of type 2 diabetes, and normal Wistar rats. We observed that soybean-treated Wistar rats present insulin resistance and defective islet insulin secretion when compared with untreated Wistar rats. The decrease in insulin secretion occurred at all concentrations of glucose and arginine tested. Furthermore we observed that soybean-treated normal islets present a significant decrease in two saturated fatty acids, myristic and heneicosanoic acids, and one monounsaturated eicosenoic acid, and the appearance of the monounsaturated erucic acid. Concerning diabetic animals, we observed that soybean-treated diabetic rats, when compared with untreated GK rats, present an increase in plasma non-fasting free fatty acids, an exacerbation of islet insulin secretion impairment in all conditions tested and a significant decrease in the monounsaturated palmitoleic acid. Altogether our results show that SO treatment results in a decrease of insulin secretion and alterations on fatty acid composition in normal and diabetic islets. Furthermore, the impairment of insulin secretion, islet erucic acid and fasting plasma insulin levels are similar in treated normal and untreated diabetic rats, suggesting that SO could have a deleterious effect on β-cell function and insulin sensitivity.

Soybean and sunflower oil‐induced insulin resistance correlates with impaired GLUT4 protein expression and translocation specifically in white adipose tissue

“…Additionally, these authors suggest that treatment with SB oil induces insulin resistance in normal rats by analyzing the HOMA index. 19 According to this study, we now demonstrate that SB decreases insulin sensitivity as assessed by the analysis of ITT. Moreover, the present study demonstrates that, as an example of the SB oil, treatment with SF oil also causes insulin resistance in normal rats.…”

Quantitative Assessment of Islets of Langerhans Encapsulated in Alginate

“…Culture of islets with soybean oil or its free fatty acid constituents can induce apoptosis and reduce insulin secretion. [61][62][63][64] Soybean oil could be especially deleterious at the high local concentration used in this study and may account for the limited cell death observed at the islet periphery. The high concentration of egg yolk phospholipid surfactants might also be toxic.…”

Metformin and atorvastatin combination further protect the liver in type 2 diabetes with hyperlipidaemia

“…Glucose tolerance test was performed 3 days before sacrifice. Plasma insulin was determined by an in-house competitive enzyme-linked immunosorbent assay (ELISA), as previously described [14,15] …”