Investigation of Gremlin-1, BMP-4 parameters in gestational diabetes mellitus patients

Gestational Diabetes Mellitus is a significant health complication that arises during pregnancy. It is defined as carbohydrate intolerance of varying severity that leads to hyperglycemia, first recognized during pregnancy. Gremlin-1 has been identified as a factor associated with adipose tissue, type 2 diabetes mellitus and insulin resistance parameters. However, to date, no study has investigated the levels of BMP-4 and its antagonist, Gremlin-1, in the context of GDM. The hypothesis of this study is that Gremlin-1 levels are increased, while BMP-4 levels are decreased in patients with GDM. The aim of this study is to compare serum levels of Gremlin-1 and BMP-4 between pregnant women with GDM and healthy pregnant controls, and to explore the potential role of Gremlin-1 in the development of diabetes during pregnancy. The study included 72 participants who presented to the Obstetrics and Gynecology outpatient clinic at Recep Tayyip Erdoğan University Training and Research Hospital. Among them, 37 comprised the healthy control group, while 35 were diagnosed with GDM. A power analysis, based on a similar study in the literature, indicated that a minimum of 72 participants would be sufficient for statistical reliability. Participants in the study were divided into groups based on their GDM status and health condition. In addition, they were categorized according to BMI as 18–25 (normal weight) and ≥25 (pre-obese/obese). Serum levels of BMP-4 and Gremlin-1 were measured using the ELISA method. In our study, a statistically significant difference was observed between the groups with respect to BMI, with the GDM group showing higher values compared to the control group. Although Gremlin-1 levels were higher in the control group and BMP-4 levels were higher in the GDM group, these differences were not statistically significant. When participants were stratified by BMI, Gremlin-1 and BMP-4 levels were higher in the normal weight group; however, no significant difference was found between the groups. A weak but significant negative correlation was identified between BMI and both Gremlin-1 and BMP-4. Furthermore, as gestational age increased, Gremlin-1 and BMP-4 levels significantly decreased. A strong and significant positive correlation was found between Gremlin-1 and BMP-4 levels. In conclusion, the finding that Gremlin-1 levels were higher in the control group while BMP-4 levels were higher in the GDM group suggests that the biomarker profile in gestational diabetes may differ from that in type 2 diabetes mellitus, potentially due to body composition changes associated with physiological weight gain during pregnancy. Moreover, the strong and positive correlation between Gremlin-1 and BMP-4 levels is consistent with the existing literature.