Maternal omega-3 fatty acid deficiency affects fetal thermogenic development and postnatal musculoskeletal growth in mice

Maternal omega-3 (n-3) polyunsaturated fatty acids (PUFAs) deficiency can affect offspring's adiposity and metabolism by modulating lipid and glucose metabolism. However, the impact of n-3 PUFA deficiency on the development of fetal thermogenesis and its consequences is not reported. Using an n-3 PUFA deficient mice, we assessed fetal interscapular brown adipose tissue (iBAT), body fat composition, insulin growth factor-1 (IGF-1), glucose transporters (GLUTs), and expression of lipid storage & metabolic proteins in the offspring. The n-3 PUFA deficiency did not change the pups' calorie intake, organ weight, and body weight. However, the offspring's skeletal growth was altered due to excess fat to lean mass, reduced tibia & femur elongation, dysregulated IGF-1 in the mother and pups (P< .05). Localization of uncoupling protein 1 (UCP1) in iBAT exhibited a reduced expression in the deficient fetus. Further, UCP1, GLUT1, GPR120 were downregulated while FABP3, ADRP, GLUT4 expressions were upregulated in the BAT of the deficient offspring (P< .05). The deficiency decreased endogenous conversion of the n-3 LCPUFAs from their precursors and upregulated SCD1, FASN, and MFSD2A mRNAs in the liver (P< .05). An altered musculoskeletal growth in the offspring is associated with impaired browning of the fetal adipose, dysregulated thermogenesis, growth hormone, and expression of glucose and fatty acid metabolic mediators due to maternal n-3 PUFA deficiency. BAT had higher metabolic sensitivity compared to WAT in n-3 PUFA deficiency. Maternal n-3 PUFA intake may prevent excess adiposity by modulating fetal development of thermogenesis and skeletal growth dynamics in the mice offspring.

Dietary incorporation of whey protein isolate and galactooligosaccharides exhibits improvement in glucose homeostasis and insulin resistance in high fat diet fed mice

Background:

This study was planned to investigate the effectiveness of the whey protein isolate (WPI) of high purity and a galactooligosaccharides (GOS) preparation on glucose homeostasis and insulin resistance in high fat diet (HFD) (45.47% energy from fat) fed conditions in C57BL/6J mice.

Methods:

Fasting blood glucose level, serum insulin, and glucagon-like peptide-1 (enzyme-linked immunosorbent assay) were measured; also, homeostasis model assessment of insulin resistance (HOMA-IR) was determined in different treatment groups. mRNA expression of gluconeogenesis genes in liver and small intestine tissues was analyzed by quantitative real time-polymerase chain reaction.

Results:

Dietary incorporation of WPI and GOS was observed to significantly resist (P < 0.001) the HFD-induced increase in blood glucose levels indicating a mitigating effect on glycemic load. It is important to note that no additive effects of administration of WPI and GOS could be observed. The administration of WPI and GOS exhibited maximum resistance (37.8%) to the rise in insulin level. Thus, the resistance to the increase in HOMA-IR was also noticed on the dietary incorporation of two functional ingredients . The positive effects on mRNA expression of phosphoenolpyruvate carboxykinase and glucose 6-phosphatase could be detected in liver only.

Conclusion:

Both types of functional components exhibit potential to improve glucose homeostasis under HFD fed conditions. Resistance to HFD-induced hyperinsulinemia and HOMA-IR is also recorded .