Circulating Insulin-like peptide 5 levels closely linked to insulin resistance among patients with PCOS

A new study published in Journal of Diabetes and its Complications suggests that Circulating Insulin-like peptide 5 levels are closely linked to insulin resistance among patients with PCOS. This implies that the relationship between circulating Insulin-like peptide 5 (INSL5) levels and polycystic ovary syndrome (PCOS) may be due to increased insulin resistance.

Both in vitro and in vivo metabolic systems benefit from insulin-like peptide 5. Therefore, it was hypothesized in this work by Yijie Chen and colleagues that INSL5 levels are related to the occurrence of insulin resistance (IR) and polycystic ovarian syndrome (PCOS).

An enzyme-linked immunosorbent test was used to determine the levels of circulating INSL5 in the PCOS group (n = 101) and control group (n = 78) groups. Regression models were used to assess the connection between INSL5 and IR.

The key findings of this study were:

1. In those with PCOS, the levels of circulating INSL5 were higher (P 0.001), and they were also substantially correlated with the homeostasis model evaluation of insulin resistance (HOMA-IR, r = 0.434, P 0.001; HOMA-IS, r = 0.432; QUICKI, r = 0.504, P 0.001) and insulin resistance.

2. After adjusting for relevant confounders, the participants with the highest tertile of INSL5 levels were more likely to develop PCOS (odds ratio: 12.591, 95% confidence range 2.616-60.605) than those with the lowest tertile.

3. After controlling for covariates, multiple linear regression analysis also revealed an independent relationship between INSL5 levels and HOMA-IR ( = 0.024, P 0.001).

The findings of this study demonstrated a favorable correlation between the prevalence of PCOS in the Chinese population and the levels of circulating INSL5. Several metabolic-hormonal markers, such as insulin resistance and lipid metabolism parameters, were correlated with INSL5. Furthermore, these findings suggested that IR is probably a mediator in the link between INSL5 and PCOS. Additional research is required to determine the potential function of INSL5.

Reference:

Chen, Y., Chen, J., Li, Y., Wu, Y., Wu, X., Zhang, H., & Zhang, Z. (2023). Insulin-like peptide 5 is associated with insulin resistance in women with polycystic ovary syndrome. In Journal of Diabetes and its Complications (Vol. 37, Issue 7, p. 108493). Elsevier BV. https://doi.org/10.1016/j.jdiacomp.2023.108493