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Developmental Biology - Immune System

Breastfeeding Crucial in Preventing Diabetes

New research shows that breastfeeding until six months of age is crucial to preventing diabetes in humans...

The World Health Organization recommends breastfeeding as the sole source of nutrition for infants until six months of age, as this helps reduce child morbidity and mortality. In contrast, early weaning is associated with both the development of obesity and Type 2 diabetes by adulthood.

The research is published in the Journal of Physiology.

Research at Rio de Janeiro State University led by Patricia Lisboa, showed how weaning rat pups early increased insulin secretion in adolescent males and later would increase it in both genders by the time they reached adulthood. Adolescence in male mouse pups is equivalent to adolescence in humans. But in rats, adolescence is defined as ranging from age 35 to 55 days after birth.
Increased insulin secretion is indicative of developing insulin resistance, meaning a reduced responsiveness to insulin. To compensate for this, the body secretes more insulin to try and regulate its high blood sugar.

Increased insulin secretion in adolescent mouse pups indicates their susceptibility to Type 2 diabetes. But all mouse offspring weaned early will become diabetic by adulthood.
"There are many causes of Type 2 diabetes, but not breastfeeding for long enough, is one we can guard against. Understanding the increased susceptibility to Type 2 diabetes as a result of early weaning will help us develop the best public health guidance."

Patricia Christina Lisboa PhD, Departamento de Cięncias Fisiológicas, Instituto de Biologia, Universidade do Estado do Rio de Janeiro, Brazil.

Abstract Key points

• The World Health Organization recommends exclusive breastfeeding until six months of age as an important strategy to reduce child morbidity and mortality.

• Studies have associated early weaning with the development of obesity and type 2 diabetes in adulthood;

• In our model, we demonstrated that early weaning leads to increased insulin secretion in adolescent males and reduced insulin secretion in adult offspring;

• Early weaned males exhibit insulin resistance in skeletal muscle;

• Early weaning did not change insulin signalling in the muscle of female offspring;

• Taking into account that insulin resistance is one of the primary factors for the development of T2DM, this work demonstrates the importance of breastfeeding in the fight against this disease.

Early weaning (EW) leads to short and long-term obesity and diabetes. This phenotype is also observed in experimental models, in which early-weaned males exhibit abnormal insulinemia in adulthood. However, studies regarding the effect of EW on pancreatic islets are rare. We investigated the mechanisms by which glycemic homeostasis is altered in EW models through evaluations of insulin secretion and its signalling pathway in offspring. Lactating Wistar rats and their pups were divided into the following groups: nonpharmacological EW (NPEW); mothers were wrapped with an adhesive bandage on the last 3 days of lactation; pharmacological EW (PEW); mothers received bromocriptine to inhibit prolactin (1 mg/kg BM/day) on the last 3 days of lactation; and control (C); pups underwent standard weaning at PN21. Offspring of both sexes were euthanized at PN45 and PN180. At PN45, EW males showed higher insulin secretion (vs C). At PN170, PEW males exhibited hyperglycemia in an oGTT (vs C and NPEW). At PN180, EW male offspring were heavier; however, both sexes showed higher visceral fat. Insulin secretion was lower in EW offspring of both sexes. Males from both EW groups had lower glucokinase in islets, but unexpectedly, PEW males showed higher GLUT2, than C. EW males exhibited lower insulin signalling in muscle. EW females exhibited no changes in these parameters compared with C. We demonstrated distinct alterations in the insulin secretion of EW rats at different ages. Despite the sex dimorphism in insulin secretion in adolescence, both sexes showed impaired insulin secretion in adulthood due to EW.

Carla Bruna Pietrobon, Rosiane Aparecida Miranda, Iala Milene Bertasso, Paulo Cezar de Freitas Mathias, Maria Lúcia Bonfleur, Sandra Lucinei Balbo, Marise Auxiliadora de Barros Reis, Márcia Queiroz Latorraca, Vanessa Cristina Arantes, Elaine de Oliveira, Patrícia Cristina Lisboa and Egberto Gaspar de Moura.

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Dec 25 2019   Fetal Timeline   Maternal Timeline   News 


The World Health Organization recommends breastfeeding as the sole source of nutrition for infants until six months of age. In contrast, early weaning is associated with both obesity and Type 2 diabetes by adulthood. CREDIT Public Domain. No copyright infringement intended.

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