Litter Size Reduction Induces Metabolic and Histological Adjustments in Dams throughout Lactation with Early Effects on Offspring.

In the present study we analyzed morphological and metabolic alterations in dams nursing small litters and their consequences to offspring throughout lactation. Offspring sizes were adjusted to Small Litter (SL, 3 pups/ dam) and Normal Litter (NL, 9 pups/ dam). Body weight, food intake, white adipose tissue (WAT) content, histological analysis of the pancreas, mammary gland (MG) and brown adipose tissue (BAT) as well as, plasma parameters and milk composition were measured in dams and pups on the 7th, 14th and 21st days of lactation. In general, SL-dams presented higher body weight and retroperitoneal fat content, elevated fat infiltration in BAT, reduced islets size and hyperglycemia throughout lactation in relation to NL-dams (p<0.05). Moreover, MG from SL-dams had reduced alveoli development and high adipocytes content, resulting in milk with elevated energetic value and fat content in relation to NL-dams (p<0.05). Maternal states influenced offspring anthropometric conditions during lactation, offspring-SL displayed higher body weight and growth, hyperglycemia, augmented lipid deposition in BAT and elevated islet. Thus, maternal histological and metabolic changes are due to modifications to nursing small litters and reinforce the importance of preserving maternal health during lactation avoiding early programming effects on offspring preventing metabolic consequences later in life.

O tratamento com isoflavonas mimetiza a ação do estradiol no acúmulo de gordura em ratas ovariectomizadas / Treatment with isoflavones replaces estradiol effect on the tissue fat accumulation from ovariectomized rats

OBJETIVO: As isoflavonas (ISO) presentes na soja são consideradas fitoestrógenos. A administração de fitoestrógenos tem efeito benéfico nos distúrbios da pós-menopausa que são caracterizados pela suspensão da função ovariana com declínio da secreção de estrogênio e conseqüentes desajustes histomorfológicos e metabólicos. O objetivo do presente estudo foi investigar o efeito da suplementação com ISO sobre a espessura do endométrio uterino, o acúmulo de gordura tecidual, o colesterol HDL e a glicose plasmática de ratas ovariectomizadas (OVX). MÉTODOS: Ratas Wistar com 60 dias de vida sofreram cirurgia bilateral para retirada dos ovários. Após o período de 8 dias de recuperação foram divididas em três grupos: falso operada (GC), OVX não-tratadas com ISO (GI) e as OVX suplementadas com ISO (GII). Foram retirados e pesados o útero, as gorduras uterinas e retroperitoneais. Também foram coletadas amostras de sangue para dosagem da concentração de HDL e glicose. RESULTADOS: A OVX promoveu atrofia do endométrio, diminuição do peso do útero e diminuição do HDL. O tratamento com ISO promoveu diminuição dos estoques de gorduras uterina e retroperitoneal, aumento de HDL e redução da glicemia, porém não teve efeito uterotrófico. CONCLUSÕES: Os dados do presente estudo mostram que o tratamento com ISO promove redução da adiposidade, o que pode estar relacionado à redução da lipogênese e ao aumento da lipólise.

OBJECTIVE: Isoflavones (ISO) present in soybean are named phytoestrogens because they show estrogen effect. The use of isoflavones has beneficial effect in disturbance of post-menopause, which is characterized by ovarian function suppression. Decreasing of estrogen secretion and consequent morphologic and metabolic disarrangements are observed in female hormonal decline. The aim of present work was to investigate the effect of ISO on the fat accretion of uterin endometric tissue, and HDL and glucose blood concentration from ovariectomized rats (OVX). METHODS: Female Wistar rats with 60 days-old were submitted a surgery to remove bilaterally the ovarium. After 8-day recovery period the animals were distributed into three groups: sham operate (GC); OVX ISO untreated (GI) and OVX supplemented with ISO (G II). Total uterus mass, uterus fat and retroperitoneal fat pad, were removed, washed and weighted. Samples of uterus were histological processed to measure endometrium thickness. Blood samples were also collected to analyze the concentration of HDL and glucose. The OVX caused endometric atrophy, decrease of uterus weight and HDL reduction. The treatment with ISO provoked decrease of uterin and retroperitoneal fat pad. HDL increase and glycemia reduction were also observed. However, there was no uterotrophic effect. CONCLUSIONS: ISO treatment causes decrease in tissue fat accretion from ovariectomized rats.

[Treatment with isoflavones replaces estradiol effect on the tissue fat accumulation from ovariectomized rats]. / O tratamento com isoflavonas mimetiza a ação do estradiol no acúmulo de gordura em ratas ovariectomizadas.

OBJECTIVE: Isoflavones (ISO) present in soybean are named phytoestrogens because they show estrogen effect. The use of isoflavones has beneficial effect in disturbance of post-menopause, which is characterized by ovarian function suppression. Decreasing of estrogen secretion and consequent morphologic and metabolic disarrangements are observed in female hormonal decline. The aim of present work was to investigate the effect of ISO on the fat accretion of uterine endometric tissue, and HDL and glucose blood concentration from ovariectomized rats (OVX). METHODS: Female Wistar rats with 60 days-old were submitted a surgery to remove bilaterally the ovarium. After 8-day recovery period the animals were distributed into three groups: sham operate (GC); OVX ISO untreated (GI) and OVX supplemented with ISO (G II). Total uterus mass, uterus fat and retroperitoneal fat pad, were removed, washed and weighted. Samples of uterus were histological processed to measure endometrium thickness. Blood samples were also collected to analyze the concentration of HDL and glucose. The OVX caused endometric atrophy, decrease of uterus weight and HDL reduction. The treatment with ISO provoked decrease of uterine and retroperitoneal fat pad. HDL increase and glycemia reduction were also observed. However, there was no uterotrophic effect. CONCLUSIONS: ISO treatment causes decrease in tissue fat accretion from ovariectomized rats.