Gestational Diabetes Mellitus Remodels the Fetal Brain Fatty Acid Profile Through Placenta-Brain Lipid Axis in C57BL/6J Mice

Maternal Gestational Diabetes Mellitus and High-Fat Diet Influenced Hepatic Polyunsaturated Fatty Acids Profile in the Offspring of C57BL/6J Mice

SCOPE

This research examines the effects of maternal high-fat (HF) diet and gestational diabetes mellitus (GDM) on offspring lipid metabolism and polyunsaturated fatty acids (PUFA) profile.

METHODS AND RESULTS

GDM is induced using the insulin receptor antagonist S961. Weaning offspring are categorized into HF-GDM, HF-CON, NC-GDM, and NC-CON groups based on maternal diet or GDM. Adult offspring are then grouped into NC-CON-NC, NC-CON-HF, NC-GDM-NC, NC-GDM-HF, HF-CON-NC, HF-CON-HF, HF-GDM-NC, and HF-GDM-HF according to dietary patterns. Gas chromatography determines PUFA composition. Western blot assesses PI3K/Akt signaling pathway-related protein expression. Feeding a normal chow diet until adulthood improves the distribution of hepatic PUFA during weaning across the four groups. PI3K expression is upregulated during weaning in HF-CON and HF-GDM, particularly in HF-CON-NC and HF-GDM-NC, compared to NC-CON-NC during adulthood. Akt expression increases in NC-GDM-NC after weaning with a normal diet. The hepatic PUFA profile in HF-CON-HF significantly distinguishes among the maternal generation health groups. Maternal HF diet exacerbates the combined impact of maternal GDM and offspring HF diet on hepatic PUFA and PI3K/Akt signaling pathway-related proteins during adulthood.

CONCLUSIONS

Early exposure to HF diets and GDM affects hepatic PUFA profiles and PI3K/Akt signaling pathway protein expression in male offspring during weaning and adulthood.

Mfsd2a regulates the blood-labyrinth-barrier formation and function through tight junctions and transcytosis

The Blood-Labyrinth Barrier (BLB) is pivotal for the maintenance of lymphatic homeostasis within the inner ear, yet the intricacies of its development and function are inadequately understood. The present investigation delves into the contribution of the Mfsd2a molecule, integral to the structural and functional integrity of the Blood-Brain Barrier (BBB), to the ontogeny and sustenance of the BLB. Our empirical findings delineate that the maturation of the BLB in murine models is not realized until approximately two weeks post-birth, with preceding stages characterized by notable permeability. Transcriptomic analysis elucidates a marked augmentation in Mfsd2a expression within the lateral wall of the cochlea in specimens exhibiting an intact BLB. Moreover, both in vitro and in vivo assays substantiate that a diminution in Mfsd2a expression detrimentally impacts BLB permeability and structural integrity, principally via the attenuation of tight junction protein expression and the enhancement of endothelial cell transcytosis. These insights underscore the indispensable role of Mfsd2a in ensuring BLB integrity and propose it as a viable target for therapeutic interventions aimed at the amelioration of hearing loss.

Effect of high-fat diet on the fatty acid profiles of brain in offspring mice exposed to maternal gestational diabetes mellitus

OBJECTIVE

Fatty acids play a critical role in the proper functioning of the brain. This study investigated the effects of a high-fat (HF) diet on brain fatty acid profiles of offspring exposed to maternal gestational diabetes mellitus (GDM).

METHODS

Insulin receptor antagonist (S961) and HF diet were used to establish the GDM animal model. Brain fatty acid profiles of the offspring mice were measured by gas chromatography at weaning and adulthood. Protein expressions of the fatty acid transport pathway Wnt3/β-catenin and the target protein major facilitator superfamily domain-containing 2a (MFSD2a) were measured in the offspring brain by Western blot.

RESULTS

Maternal GDM increased the body weight of male offspring (P < 0.05). In weaning offspring, factorial analysis showed that maternal GDM increased the monounsaturated fatty acid (MUFA) percentage of the weaning offspring's brain (P < 0.05). Maternal GDM decreased offspring brain arachidonic acid (AA), but HF diet increased brain linoleic acid (LA) (P < 0.05). Maternal GDM and HF diet reduced offspring brain docosahexaenoic acid (DHA), and the male offspring had higher DHA than the female offspring (P < 0.05). In adult offspring, factorial analysis showed that HF diet increased brain MUFA in offspring, and male offspring had higher brain MUFA than female offspring (P < 0.05). The HF diet increased brain LA in the offspring. Male offspring had higher level of AA than female offspring (P < 0.05). HF diet reduced DHA in the brains of female offspring. The brain protein expression of β-catenin and MFSD2a in both weaning and adult female offspring was lower in the HF + GDM group than in the CON group (P < 0.05).

CONCLUSIONS

Maternal GDM increased the susceptibility of male offspring to HF diet-induced obesity. HF diet-induced adverse brain fatty acid profiles in both male and female offspring exposed to GDM.