Anti-Diabetic Effects of the Ethyl-Acetate Fraction of Trichilia catigua in Streptozo-tocin-Induced Type 1 Diabetic Rats.

BACKGROUND/AIMS: Trichilia catigua A. Juss., known as "catuaba" in Brazil, has been popularly used as a tonic for fatigue, impotence and memory deficits. Previously, our group demonstrated that the ethyl-acetate fraction (EAF) of T. catigua has antioxidant and anti-inflammatory effects. The present study evaluated the anti-diabetic activity of EAF in type 1 diabetic rats. METHODS: Male Wistar rats were divided into four groups (N: non-diabetic group, D: type 1 diabetic group, NC: non-diabetic + EAF group and DC: type 1 diabetic + EAF group). The latter two groups were treated with 200 mg/kg EAF. Type 1 diabetes was induced by intravenous streptozotocin (STZ) injection (35 mg/kg). Starting two days after STZ injection, EAF was administered daily by gavage for 8 weeks. RESULTS: EAF attenuated body mass loss and reduced food and water intake. EAF improved hyperglycaemia and other biochemical parameters, such as alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Furthermore, the number of pancreatic ß-cells and the size of the islets had increased by ß-cell proliferation in the DC group. EAF promoted reduction in kidney tissue damage in STZ-induced diabetic rats by reduction of renal fibrosis. CONCLUSION: The present study showed that EAF improves glucose homeostasis and endocrine pancreas morphology and inhibits the development of diabetic nephropathy in STZ-induced diabetic rats.

Chronic Glibenclamide Treatment Attenuates Walker-256 Tumour Growth in Prediabetic Obese Rats.

BACKGROUND/AIMS: The sulphonylurea glibenclamide (Gli) is widely used in the treatment of type 2 diabetes. In addition to its antidiabetic effects, low incidences of certain types of cancer have been observed in Gli-treated diabetic patients. However, the mechanisms underlying this observation remain unclear. The aim of the present work was to evaluate whether obese adult rats that were chronically treated with an antidiabetic drug, glibenclamide, exhibit resistance to rodent breast carcinoma growth. METHODS: Neonatal rats were treated with monosodium L-glutamate (MSG) to induce prediabetes. Control and MSG groups were treated with Gli (2 mg/kg body weight/day) from weaning to 100 days old. After Gli treatment, the control and MSG rats were grafted with Walker-256 tumour cells. After 14 days, grafted rats were euthanized, and tumour weight as well as glucose homeostasis were evaluated. RESULTS: Treatment with Gli normalized tissue insulin sensitivity and glucose tolerance, suppressed fasting hyperinsulinaemia, reduced fat tissue accretion in MSG rats, and attenuated tumour growth by 27% in control and MSG rats. CONCLUSIONS: Gli treatment also resulted in a large reduction in the number of PCNA-positive tumour cells. Although treatment did improve the metabolism of pre-diabetic MSG-rats, tumour growth inhibition may be a more direct effect of glibenclamide.

A Long-term Estrogen Deficiency in Ovariectomized Mice is Associated with Disturbances in Fatty Acid Oxidation and Oxidative Stress.

OBJECTIVE: The aim of this work was to evaluate the changes caused by estrogen deficiency in lipid metabolism. METHODS: This study encompassed direct measurements of plasma biochemical analyses, liver lipid contents, and assessments of the mitochondrial ß-oxidation capacity as well as an evaluation of the liver redox status in an animal model of estrogen deficiency. RESULTS: When compared with control mice, the livers of ovariectomized (OVX) mice presented considerable accretions in their lipid contents, which were accompanied by increased levels of lipid peroxidation in liver homogenates and mitochondria from OVX groups and decreased reduced glutathione (GSH) contents. In isolated mitochondria, estrogen deficiency inhibited mitochondrial ß-oxidation of fatty acids irrespective of their chain length. The liver mitochondrial and peroxisomal H2O2 generations in OVX mice were increased. Additionally, the activities of all antioxidant enzymes assessed were decreased. CONCLUSION: These data provide one potential explanation for the increased susceptibility to metabolic diseases observed after menopause.

OBJETIVO: O objetivo desse trabalho foi avaliar as alterações causadas pela deficiência estrogênica no metabolismo de lipídeos. MéTODOS: Este estudo abrangeu análises bioquímicas plasmáticas, verificação de conteúdo lipídico do fígado e avaliações da capacidade de ß-oxidação mitocondrial e do estado redox do fígado em um modelo animal de deficiência estrogênica. RESULTADOS: Os fígados das camundongas ovariectomizadas (OVXs) apresentaram acréscimos consideráveis no conteúdo de lipídeos, que foram acompanhados por aumento de peroxidação lipídica em homogenatos e mitocôndrias de fígado e diminuição do conteúdo de glutationa reduzida (GSH) quando comparadas as camundongas do grupo controle. Nas mitocôndrias isoladas, a deficiência estrogênica causou a inibição da ß-oxidação mitocondrial independentemente do comprimento da cadeia dos ácidos graxos. A geração mitocondrial e peroxissomal de H2O2 apresentou-se aumentada em camundongas OVXs. Além disso, as atividades de todas as enzimas antioxidantes avaliadas foram diminuídas. CONCLUSãO: Esses dados fornecem uma explicação potencial para o aumento da suscetibilidade às doenças metabólicas observadas após a menopausa.

Morphoquantitative evaluation of the duodenal myenteric neuronal population in rats fed with hypoproteic ration.

The purpose of this work was to analyze the morphoquantitative behavior of the neurons of the myenteric plexus, as well as the morphometry of the duodenal wall, in adult rats fed with normoproteic (22%) and hypoproteic (8%) rations, killed at the age of 345 days. For neuronal assessments duodenal whole-mounts stained with the Giemsa method were used, and for the evaluation of the duodenal wall routine histological processing and staining with Hematoxilin-Eosin were employed. The means of the number of neurons in 80 microscopic fields (12.72 mm2) and of the size of the neuronal cell bodies did not reveal statistically significant differences between the groups, but there was a greater incidence of large neurons in the protein restriction group (RP). The duodenum was markedly smaller in the RP group and, although there was no difference in the thickness of its wall, the mucosa was larger and the muscular layer was smaller in group RP. It was concluded that the neuronal and non-neuronal components of the duodenum adjust themselves to the nutritional condition, assuring the maintenance of their functions.

A long-term estrogen deficiency in ovariectomized mice is associated with disturbances in fatty acid oxidation and oxidative stress / Deficiência de estrogênio em longo prazo em camundongas ovarietcomizadas está associada a distúrbios na oxidação de ácidos graxos e estresse oxidativo

Abstract Objective The aim of this work was to evaluate the changes caused by estrogen deficiency in lipid metabolism. Methods This study encompassed direct measurements of plasma biochemical analyses, liver lipid contents, and assessments of the mitochondrial β-oxidation capacity as well as an evaluation of the liver redox status in an animal model of estrogen deficiency. Results When compared with control mice, the livers of ovariectomized (OVX) mice presented considerable accretions in their lipid contents, which were accompanied by increased levels of lipid peroxidation in liver homogenates andmitochondria from OVX groups and decreased reduced glutathione (GSH) contents. In isolated mitochondria, estrogen deficiency inhibited mitochondrial β-oxidation of fatty acids irrespective of their chain length. The liver mitochondrial and peroxisomal H2O2 generations in OVX mice were increased. Additionally, the activities of all antioxidant enzymes assessed were decreased. Conclusion These data provide one potential explanation for the increased susceptibility to metabolic diseases observed after menopause.

Resumo Objetivo O objetivo desse trabalho foi avaliar as alterações causadas pela deficiência estrogênica no metabolismo de lipídeos. Métodos Este estudo abrangeu análises bioquímicas plasmáticas, verificação de conteúdo lipídico do fígado e avaliações da capacidade de β-oxidação mitocondrial e do estado redox do fígado em um modelo animal de deficiência estrogênica. Resultados Os fígados das camundongas ovariectomizadas (OVXs) apresentaram acréscimos consideráveis no conteúdo de lipídeos, que foram acompanhados por aumento de peroxidação lipídica em homogenatos e mitocôndrias de fígado e diminuição do conteúdo de glutationa reduzida (GSH) quando comparadas as camundongas do grupo controle. Nas mitocôndrias isoladas, a deficiência estrogênica causou a inibição da β-oxidação mitocondrial independentemente do comprimento da cadeia dos ácidos graxos. A geração mitocondrial e peroxissomal de H2O2 apresentou-se aumentada em camundongas OVXs. Além disso, as atividades de todas as enzimas antioxidantes avaliadas foram diminuídas. Conclusão Esses dados fornecem uma explicação potencial para o aumento da suscetibilidade às doenças metabólicas observadas após a menopausa.

Study of the myenteric plexus of the ileum of rats subjected to proteic undernutrition

Con el objetivo de verificar los efectos de la desnutrición proteica sobre el plexo mientérico del íleon, fueron utilizados 20 ratas del linaje wistar, cuyas madres fueron desnutridas en los períodos de gestación y/o lactacia sometidas a sacrificio a los 60 días de edad. Se realizaron preparados de membrana del íleon teñidos con GIEMSA, para observación de las neuronas mientéricas y posteriores análisis y cuantificación. Verificamos que la desnutrición proteica no provoca reducción en el número de neuronas mientéricas por cm2 de íleon, y que las neuronas medias con basofilia intermediaria predominan en todos los grupos

Morphological study of the reproductive cycle and variability in the levels of glucose, glycogen and lipid along the year in the domestic duck (Anas platyrhynchus) - DOI: 10.4025/actascianimsci.v27i3.1208 / Estudo morfológico do ciclo reprodutivo e variabilidade nos níveis de glicose, de glicogênio e de lipídeo ao longo do ano em pato doméstico (Anas platyrhynchus) - DOI: 10.4025/actascianimsci.v27i3.1208

Histologic studies on the seminiferous epithelium were performed to determine the reproductive annual cycle of domestic duck in mesothermic tropical region and to correlate it with metabolic parameters such as blood glucose, hepatic and muscular glycogen and lipids, which are basic metabolic substrates related to the reproductive process. The annual reproductive cycle of the duck could be divided in four successive phases along the year, which are named reproductive, regressive, quiescent and recrudescent phases. The reproductive phase began in winter (July) reaching its maximum peak in October. The regressive phase occurred in the end of spring and in the beginning of summer (December). The quiescent phase started in the summer between January and February. The recrudescent phase occurred in autumn and winter (June) when the spermatogenetic process resumed. Concerning the energetic metabolism only the blood glucose was related to the reproductive cycle, giving energetic support to this reproductive process

Estudos histológicos do epitélio seminífero foram realizados para determinar o ciclo reprodutivo anual do pato doméstico na região mesotérmica tropical e correlacioná-lo aos parâmetros de glicose sangüínea, de glicogênio e de lipídeos hepáticos e musculares, substratos metabólicos básicos ligados ao processo reprodutivo. O ciclo reprodutivo anual do pato pôde ser dividido em quatro fases sucessivas ao longo do ano, denominadas de reprodução, de regressão, de quiescência e de recrudescência testicular. A fase reprodutiva iniciou-se na estação de inverno (julho), atingindo seu pico máximo em outubro. A fase de regressão ocorreu no final da primavera (novembro) e no início do verão (dezembro). A fase de quiescência testicular iniciou-se no verão (janeiro e fevereiro). A fase de recrudescência ocorreu do outono (março) até o inverno (junho), com a retomada do processo espermatogenético. Quanto ao metabolismo energético, somente a glicose sangüínea esteve correlacionada ao ciclo reprodutivo do pato, fornecendo suporte energético para o processo reprodutivo

Morphoquantitative evaluation of the duodenal myenteric neurona} population in rats fed with hypoproteic ration

The purpose of this work was to analyze the morphoquantitative behavior of the neurons of the myenteric plexus, as well as the morphometry of the duodenal wall, in adult rats fed with normoproteic (22%) and hypoproteic (8%) rations, killed at the age of 345 days. For neuronal assessments duodenal wholernounts stained with the Giemsa method were used, and for the evaluation of the duodenal wall routine histological processing and staining with Hematoxilin-Eosin were employed. The means of the number of neurons in 80 microscopic fields (12.72 mm2) and of the size of the neuronal cell bodies did not reveal statistically significant differences between the groups, but there was a greater incidence of large neurons in the protein restriction group (RP). The duodenum was markedly smaller in the RP group and, although there was no difference in the thickness of its wall, the mucosa was larger and the muscular layer was smaller in group RP. It was concluded that the neuronal and non-neuronal components of the duodenum adjust themselves to the nutritional condition, assuring the maintenance of their functions