Dietary calcium supplementation in adult rats reverts brown adipose tissue dysfunction programmed by postnatal early overfeeding.

Brown adipose tissue (BAT) dysfunction is associated with obesity and its comorbidities, such as hypertension, and the improvement of BAT function seems important for obesity management. Here we investigated the effects of dietary calcium supplementation on BAT autonomic nerve activity, sympathoadrenal function and cardiovascular parameters in adult obese rats that were raised in small litters (SL group). Three days after birth, SL litters were adjusted to three pups to induce early overfeeding. The control group remained with 10 pups/litter until weaning (NL group). At PN120, the SL group was randomly divided into the following: rats fed with standard chow (SL) and rats fed with dietary calcium carbonate supplementation (SL-Ca, 10g/kg chow). Animals were killed either at PN120 or PN180. At both ages, SL rats had higher BAT autonomic nervous system activity, mass and adipocyte area, as well as increased heart rate and blood pressure (systolic and diastolic); 2 months of calcium supplementation normalized these parameters. At PN180 only, UCP1 and TRß1 in BAT were decreased in SL rats. These changes were also prevented by calcium treatment. Also at PN180, the SL group presented higher tyrosine hydroxylase and adrenal catecholamine contents, as well as lower hypothalamic POMC and MC4R contents. Calcium supplementation did not revert these alterations. Thus, we demonstrated that dietary calcium supplementation was able to improve cardiovascular parameters and BAT thermogenesis capacity in adult animals that were early overfed during lactation.

Maternal flaxseed oil intake during lactation changes body fat, inflammatory markers and glucose homeostasis in the adult progeny: role of gender dimorphism.

We evaluated maternal flaxseed oil intake during lactation on body composition, lipid profile, glucose homeostasis and adipose tissue inflammation in male and female progeny at adulthood. Lactating rats were divided into the following: control 7% soybean oil (C), hyper 19% soybean oil (HS) and hyper 17% flaxseed oil+2% soybean oil (HF). Weaned pups received a standard diet. Offspring were killed in PN180. Male HF presented higher visceral adipose tissue (VAT) and triacylglycerol, and female HF showed insulin resistance. Both male and female HF had hyperleptinemia, and only male HF had hyperprolactinemia. In VAT, male HF presented lower PPAR-γ expressions and higher TNF-α, IL-6, IL-1ß and IL-10 expressions; in subcutaneous adipose tissue (SAT), they presented lower PPAR-γ and TNF-α expressions. Female HF presented higher leptin, as well as lower adiponectin, TNF-α, IL-6 and IL-1ß expressions in VAT and lower TNF-α in SAT. Flaxseed oil during lactation leads to gender-specific effects with more adiposity and dyslipidemia in male and insulin resistance in female. Higher prolactin and inflammatory cytokines in male could play a role in these gender differences. We suggest that the use of flaxseed oil during lactation increases metabolic syndrome risk in the adult progeny.

Flaxseed oil during lactation changes milk and body composition in male and female suckling pups rats.

We have reported several changes in neonate or adult offspring after the maternal use of whole flaxseed or its components. However, it is unknown the use of higher oil intake in the neonatal period. Here we evaluated the effects of high maternal intake of flaxseed oil during lactation upon milk and body composition in male and female offspring. Lactating rats were divided into: (1) control (C, n=10), 7% soybean oil; (2) hyper 19% soybean oil (HS, n=10); and (3) hyper 17% flaxseed oil+2% soybean oil (HF, n=10). Dams and offspring were killed at weaning. HS and HF dams, male and female offspring presented lower body weight during lactation. HF mothers presented lower body and visceral fat masses. HF male offspring presented lower body and subcutaneous fat masses. HS and HF milk presented lower triglycerides (TG) and cholesterol. HF male and female offspring showed lower triglyceridemia and insulinemia, but no changes in glycemia and leptinemia. The higher intake of flaxseed oil during lactation reduced the body weight of mothers and offspring, decreases milk lipids and apparently increases insulin sensitivity in this critical period of life. Those changes may explain the previously reported programming effect of maternal flaxseed intake during lactation.