Background: Obesity during pregnancy heightens cardiovascular disease (CVD) risk in women by compounding the physiological demands of pregnancy, such as increased blood volume and altered cardiac output. Current recommendations advise pre-pregnancy weight loss. GLP-1 receptor agonists show promise in weight management with improved cardiovascular outcomes, but their use pre-pregnancy remains understudied.
Aim: To characterise the effects of pre-pregnancy liraglutide treatment on post-pregnancy cardiac protein expression in a murine model of high-fat diet–induced obesity.
Methods: Female C57BL/6 mice were allocated to either a high-fat-diet (HFD) or chow-diet (CHOW). Liraglutide treatment (LIRA) commenced for a subset of the HFD group, after 8-weeks of diet commencement, at a dose of 0.3mg/kg. All other mice received volume matched saline. Female mice were co-housed with male mice until pregnancy was achieved, and after birth and lactation they were sacrificed (n=4/group/timepoint). Hearts were perfused with phosphate buffered saline before being snap frozen whole. After homogenisation and sample preparation proteomic analysis was completed on cardiac tissue using data-dependant acquisition, liquid chromatography mass spectrometry. Statistical analysis was completed in Spectronaught and R.
Results: In total 31 proteins were significantly different post-pregnancy between the HFD and CHOW groups. Of these 15 were significantly up-regulated and 16 were significantly down-regulated (Adj.p<0.05). Whilst both tensin 1 and Succinate-dehydrogenase-assembly-factor 3 were approximately 2-fold increase in both the CHOW and LIRA groups comparted to HFD (Adj.p<0.05), 17 of the proteins dysregulated between HFD and CHOW followed the same pattern when comparing LIRA to CHOW (Adj.p<0.05). These proteins were significantly associated with several metabolic and oxidative pathways (p<0.05).
Conclusion: Pre-pregnancy liraglutide treatment led to minimal changes in cardiac protein expression, suggesting limited cardioprotective effects after pregnancy. In contrast, the chow-fed group showed widespread alterations in protein expression, highlighting the greater impact of baseline metabolic health on postpartum cardiovascular outcomes.