Abstract
BACKGRUOUND: Galectins (gal) are glycan-binding proteins that regulate maternal adaptations during pregnancy, but their role in pregnancy-associated metabolic homeostasis is unclear. This study characterizes the maternal galectin profile in response to an oral glucose tolerance test (OGTT) in pregnant women with varying body weight. METHODS: In a two-center prospective study, pregnant women were recruited into two cohorts: low-risk (LR) with normal weight and high-risk (HR) with overweight or obesity. Circulating levels of gal-1, -3, -7, and -9 were measured at fasting, 1 hour, and 2 hours during the OGTT between 24 and 28 weeks of gestation. Correlations with clinical and metabolic parameters were assessed (HMO study: ClinicalTrials.gov Identifier NCT05496712; FitFor2 trial: trial registration number NTR1139). RESULTS: Fasting gal-3 and gal-9 were elevated in the HR cohort compared to the LR cohort. Body mass index was positively associated with gal-3 and gal-9, while gal-3 was also linked to insulin sensitivity. After glucose challenge, gal-1, -3, -7, and -9 decreased in the LR cohort; in the HR cohort, only gal-1 and gal-7 decreased after 2 hours, while gal-3 and gal-9 remained unchanged. Gal-1 correlated positively with homeostasis model assessment for insulin resistance (HOMA-IR) and inversely with insulin sensitivity across the OGTT in the LR cohort, but some of these correlations were not observed in the HR cohort. CONCLUSION: Galectins exhibited distinct patterns of association with glucose homeostasis during the second trimester of pregnancy. Gal-3 and gal-9 are associated with chronic conditions such as pre-pregnancy obesity and insulin resistance, whereas gal-1 appears to be particularly sensitive to the acute glucose challenge.