Association between plasma irisin and glucose metabolism in pregnant women is modified by dietary n‐3 polyunsaturated fatty acid intake

Abstract

Aims/Introduction The role of irisin in maternal glucose metabolism and how it would respond to dietary n‐3 polyunsaturated fatty acid (n‐3 PUFA) intake remains unclear. This study aimed to explore whether maternal plasma irisin is associated with glucose metabolism and whether this association is modified by dietary n‐3 PUFA. Materials and Methods A total of 932 pregnant women (20–28 weeks’ gestation) aged 20–45 years were recruited. Dietary n‐3 PUFA was estimated using a validated quantitative food frequency questionnaire. Plasma irisin and insulin were tested by enzyme‐linked immunosorbent assay, and insulin resistance (IR) was estimated using the homeostatic model assessment (HOMA). Gestational diabetes mellitus was diagnosed with a 75‐g oral glucose tolerance test. Adjusted multivariable linear regression and logistic regression were carried out to examine the associations between plasma irisin and glucose metabolism. The moderating effect of dietary n‐3 PUFA intake was determined by fully multiplicative models by including the interaction term. Results Maternal plasma irisin was negatively associated with HOMA‐IR and oral glucose tolerance test 0 h glucose level (β −0.250, −0.067; corrected P‐value for false discovery rate = 0.012, 0.018, respectively), positively associated with HOMA of insulin sensitivity (β 0.028; corrected P‐value for false discovery rate = 0.012), but not associated with postprandial glucose or the risk of gestational diabetes mellitus. Furthermore, we found a moderating effect of dietary n‐3 PUFA on the relationships of plasma irisin with HOMA‐IR and HOMA of insulin sensitivity; these associations were strengthened with increased n‐3 PUFA intake (β −0.037, 0.004; P = 0.014, 0.041, respectively). Conclusions Plasma irisin was negatively associated with HOMA‐IR and fasting glucose, whereas it was positively associated with HOMA of insulin sensitivity in pregnant women. We first showed that these associations were modified by dietary n‐3 PUFA intake.

The Role of Irisin throughout Women’s Life Span

“…This suggests that the increase in irisin during pregnancy is an adaptive response, to compensate for the increase in IR. Furthermore, maternal irisin showed a negative association with fasting plasma glucose (FPG) [90]. Several possible interpretations have been proposed to explain this finding.…”

“…However, it has been hard for studies to evaluate the association between irisin levels and maternal HOMA-IR, considering potential confounding variables such as age, BMI, physical activity, and nutritional status, which influence circulating irisin levels [23]. To reduce the potential influence of confounding factors, Cai et al used multiple linear regression analysis, and found an inverse association between maternal serum irisin levels and HOMA-IR [90]. This suggests that the increase in irisin during pregnancy is an adaptive response, to compensate for the increase in IR.…”

“…However, a non-significant inverse association was found between maternal irisin and 1 and 2 h glucose levels during the oral glucose tolerance test (OGTT). It is plausible that postprandial glucose levels, unlike FPG, are more likely to be influenced by external variables such as dietary carbohydrate intake and gastrointestinal absorption functions [90].…”