Temporal analysis of distribution pattern of islet cells and antioxidant enzymes for diabetes onset in postnatal critical development window in rats.

AIM: At performing a temporal analysis of the distribution pattern of islet endocrine cells and antioxidant enzymes in diabetic rats during the post-natal critical development window. MAIN METHODS: The newborns received streptozotocin (STZ) at birth for diabetes induction, and control females received the vehicle. The animals were euthanized at different lifetimes: D5, D10, D15, and D30. Morphological analysis of pancreas and biochemical assays was performed. KEY FINDINGS: The STZ-induced rats presented irregular shape of islet on D5 and there was an attempt to restore of this shape in other life moment studied. There was an increase progressive in islet area, however they maintained smaller than those of control rats, with lower labeling intensity for insulin, higher for glucagon and somatostatin, lower for SOD-1 was lower in the islets of the STZ-induced animals at all times studied and for GSH-Px in D10 and D30. SIGNIFICANCE: Although STZ-induced diabetic rats presented compensatory mechanisms to restore the mass of endocrine cells, this was not sufficient since these rats developed the diabetic state. This was confirmed by the oral glucose tolerance test from D30. In addition, the delta (δ)-cells presented ectopic location in islets, indicating a possible relationship for beta (ß)-cell mass restoration. There was a response of the pancreas to reduce the hyperglycemia in the first month of life. Furthermore, the cells from the endocrine pancreas of diabetic animals show a decline of antioxidant enzymatic, contributing to the increased susceptibility of cells to hyperglycemia-induced ROS in this postnatal critical development window.

Pancreatic islet response to diabetes during pregnancy in rats.

AIMS: The objective of this study was to assess the mechanisms underlying pancreatic islet adaptation in diabetic mothers and their pups. Additionally, the influence of pancreatic adaptations on maternal reproductive performance was also investigated. MAIN METHODS: Wistar rats were injected with streptozotocin for diabetes induction. At adulthood (3 months), all animals underwent an oral glucose tolerance test (OGTT) for glucose assessment as an inclusion criterion. Following, the animals were mated. At day 18 of pregnancy, the mothers were killed for blood collect ion to determine fasting insulin and glucagon concentrations. The pancreas was removed and processed for the immunohistochemical analysis of insulin, glucagon, somatostatin, Ki-67 and PDX-1, superoxide dismutase 1 (SOD-1), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA). The pregnant uterus was also collected for the evaluation of embryofetal loss. KEY FINDINGS: The diabetic rats showed increased glucose, serum glucagon and insulin concentrations, and embryofetal loss rates. They also showed a reduction in pancreatic islets area and percentage of cells stained for insulin, increased the percentage of non-ß cells (alpha e delta cells) stained for Ki-67, glucagon, and somatostatin. Moreover, the cells stained for somatostatin were spread across the islets and showed stronger staining for MDA and weaker staining for GSH-Px. SIGNIFICANCE: Diabetes leads to adaptive responses from the endocrine pancreas in pregnancy that especially involves non-ß cells, modifying the mantle-core structure. Nonetheless, these adaptations are not enough for glucose homeostasis and affect the maternal environment, which in turn impairs fetal development.

Effect of oral supplementation of the linoleic and gammalinolenic acids on the diabetic pregnant rats

The aim of this work was to evaluate the direct protective action of oral fatty acid supplementation against the deleterious effect of hyperglycemia on maternal reproductive outcomes; fetal growth and development on female Wistar rats. The animals were distributed into four experimental groups: G1= non-diabetic without supplementation (Control group); G2= non-diabetic treated with linoleic (LA) and gammalinolenic acid (GLA) (1 mL of Gamaline-V/day); G3= diabetic without supplementation and G4= diabetic treated with LA and GLA. Diabetes was induced by streptozotocin (40 mg/kg). At day 21 of pregnancy, the gravid uterus was weighed and dissected to count the dead and live fetuses, resorption, implantation, and corpora lutea numbers. The fetuses were analyzed for external and internal anomalies. The treatment with Gamaline-V supplementation to diabetic rats interfered in the maternal reproductive outcome (reduced number of live fetuses and embryonic implantation); however, it protected the deleterious on the incidence of congenital anomalies caused by hyperglycemia.

Neonatally induced mild diabetes in rats and its effect on maternal, placental, and fetal parameters.

The aim of this study was to assess placental changes and reproductive outcomes in neonatally induced mild diabetic dams and fetal development in their offspring. At birth, female rats were assigned either to control or diabetic group (100 mg of streptozotocin/Kg, subcutaneously). At adulthood, the female rats were mated. During pregnancy, the blood glucose levels and glucose and insulin tolerance tests were performed. At term, maternal reproductive outcomes, fetal and placental weight, and placental morphology were analyzed. Diabetic rats had smaller number of living fetuses, implantations and corpora lutea, and increased rate of embryonic loss. Placenta showed morphometric alterations in decidua area. Our results showed that mild diabetes was sufficient to trigger alterations in maternal organism leading to impaired decidua development contributing to failure in embryonic implantation and early embryonic losses. Regardless placental decidua alteration, the labyrinth, which is responsible for the maternal-fetal exchanges, showed no morphometric changes contributing to an appropriate fetal development, which was able to maintain normal fetal weight at term in mild diabetic rats. Thus, this experimental model of diabetes induction at the day of birth was more effective to reproduce the reproductive alterations of diabetic women.

Neonatally induced diabetes: liver glycogen storage in pregnant rats

The aim of this sstudy was to evaluate the liver glycogen storage in pregnant rats presenting neonatal streptozotocin-induced diabetes and to establish a relation with glycemia and insulin levels. Wistar rats were divided in to two groups: 1) Mild Diabetes (STZ) - received streptozotocin (glycemia from 120 to 300 mg/dL), 2) Control - received vehicle (glycemia below 120 mg/dL). At days 0, 7, 14 and 21 of the pregnancy, body weight and glycemia were evaluated. At day 21 of the pregnancy, the rats were anesthetized for blood and liver collection so as to determine insulin and liver glycogen, which showed no changes in the STZ group as compared to the controls. In the STZ group, maternal weight gain were lower as compared to those in the control group. Significantly increased glycemia was observed at days 0 and 14 of the pregnancy in the STZ group. Therefore, neonatally induced diabetes in the rats did not cause metabolic changes that impaired insulin and liver glycogen relation in these rats.

[Influences of lunar cycle in labor: myth or scientific finding?]. / Influência do ciclo lunar no parto: mito ou constatação científica?

Superstitions are found everywhere in our lives, and medicine, a profession that is prides itself on an evidence-based approach to treatment, is not exempt. A superstition that pervades the labor and delivery floor is that it is busier during certain phases of the lunar cycle, specifically the full moon. Although some studies have demonstrated an increase in deliveries that are related to the lunar cycle, there has been disagreement about when, in the lunar cycle, the peak volume occurs. Front to the divergence of the existent results in the literature to relate the events of the lunar cycle with deliveries, the aim of this review was to accomplish the literature in the attempt of explaining this popular culture with base in the results presented by different researchers.

Influência do ciclo lunar no parto: mito ou constatação científica?: [revisão] / Influencia del ciclo lunar en el parto: mito o constatación científica?: [revision] / Influences of lunar cycle in labor: myth or scientific finding?: [review]

Muitas superstições são encontradas em nossas vidas. Na medicina, uma profissão que se orgulha em métodos baseados em evidências para tratamentos, isso não é uma exceção. Uma superstição que abrange o parto é a influência de determinadas fases do ciclo da lua, mais especificamente a lua cheia. Embora estudos tenham demonstrado que o aumento de partos está relacionado com o ciclo lunar, existe discordância sobre quando ocorre o pico do volume de partos em cada fase da lua. Frente à divergência de resultados existentes na literatura que relaciona os eventos do ciclo lunar com parto, o objetivo desta revisão foi realizar um levantamento bibliográfico na tentativa de esclarecer esta cultura popular com base nos resultados apresentados por diferentes autores.

Superstitions are found everywhere in our lives, and medicine, a profession that is prides itself on an evidence-based approach to treatment, is not exempt. A superstition that pervades the labor and delivery floor is that it is busier during certain phases of the lunar cycle, specifically the full moon. Although some studies have demonstrated an increase in deliveries that are related to the lunar cycle, there has been disagreement about when, in the lunar cycle, the peak volume occurs. Front to the divergence of the existent results in the literature to relate the events of the lunar cycle with deliveries, the aim of this review was to accomplish the literature in the attempt of explaining this popular culture with base in the results presented by different researchers.

Se encuentran las supersticiones por todas partes en nuestras vidas, y la medicina, una profesión que tiene orgullo acerca de los tratamientos con base en evidencia, no está extinta. La influencia de ciertas fases del ciclo lunar, específicamente la luna llena, es una superstición sobre el parto. Aunque algunos estudios han demostrado un aumento en los partos que se relacionan al ciclo lunar, ha habido discordancia sobre cuando, en el ciclo lunar, el volumen máximo ocurre. Afronte a la divergencia de los resultados existentes en la literatura que relacionan los eventos del ciclo lunar con los partos, el objetivo de esta revisión era explorar la literatura en el esfuerzo de explicar esta cultura popular con la base en los resultados presentado por los diferentes investigadores.

Evaluation of placental glycogen storage in mild diabetic rats / Avaliação dos estoques de glicogênio placentário em ratas com diabete moderado

Purpose: To evaluate the placental glycogen storage and fetal development in the pregnancy of neonatally streptozocin-induced diabetic rats and to establish relation with glycemia and insulin levels. Methods: At the birth day, 147 female rats were randomly distributed in two experimental groups: 1) Non-diabetic Group (Control, n=45) - received the vehicle; 2) Diabetic Group (STZ, n=102) - received 100 mg streptozocin/kg in neonatal period. At day 0 of pregnancy, adult female rats were included in the control group when presented glycemia below 120 mg/dL and, in the group STZ with glycemia between 120 and 300 mg/dL. At day 21 of pregnancy, blood samples were collected for glycemia and insulin determination, and placentas withdrawn for placental glycogen determination. The newborns (NB) were classified in small (SGA), appropriate (AGA) and large (LGA) for gestational age. Results: Rats STZ presented higher glycemia at days 0 and 14 of pregnancy. At end of pregnancy, rats STZ showed higher proportion of NB SGA and LGA; reduced rate of NB AGA and unaltered glycemia, insulin and placental glycogen determinations. Conclusion: Mild diabetes altered the maternal glycemia in the early pregnancy, impairing future fetal development, but it caused no alteration on insulin and placental glycogen determination, confirming that this glycemic intensity was insufficient to change glycogen metabolism.

Objetivo: Avaliar os estoques de glicogênio placentário e o desenvolvimento fetal na prenhez de ratas com diabete moderado induzido no período neonatal e relacionar com glicemia e níveis de insulina. Métodos: No dia de nascimento, foram distribuídas aleatoriamente 147 ratas em dois grupos experimentais: 1) Grupo Não-diabético (Controle, n=45) - recebeu o veículo; 2) Grupo Diabético (STZ, n=102) - recebeu 100 mg streptozocin/kg peso corpóreo. No dia 0 de prenhez, foram incluídas ratas controle que apresentassem glicemia baixo de 120 mg/dL e, no grupo STZ, com glicemia entre 120 e 300 mg/dL. No 21º dia de prenhez, amostras de sangue foram coletadas para glicemia e determinação de insulina e as placentas foram retiradas para determinação de glicogênio placentário. Os recém-nascidos (RN) foram classificados em pequeno (PIP), adequado (AIP) e grande (GIP) para idade de prenhez. Resultados: As ratas STZ apresentaram glicemias maiores nos dias 0 e 14 de prenhez. No final da prenhez, as ratas STZ mostraram maior proporção de RN PIP e GIP, taxa reduzida de RN AIP e inalteração em glicemia, insulina e na determinação de glicogênio placentário. Conclusão: O diabete moderado alterou a glicemia materna no início da prenhez, prejudicando o futuro desenvolvimento placentário e fetal, mas não causou nenhuma alteração na determinação de insulina e de glicogênio placentário, confirmando que esta intensidade de glicêmica foi insuficiente para modificar o metabolismo de glicogênio.

Evaluation of placental glycogen storage in mild diabetic rats.

PURPOSE: To evaluate the placental glycogen storage and fetal development in the pregnancy of neonatally streptozocin-induced diabetic rats and to establish relation with glycemia and insulin levels. METHODS: At the birth day, 147 female rats were randomly distributed in two experimental groups: 1) Non-diabetic Group (Control, n=45) - received the vehicle; 2) Diabetic Group (STZ, n=102) - received 100 mg streptozocin/kg in neonatal period. At day 0 of pregnancy, adult female rats were included in the control group when presented glycemia below 120 mg/dL and, in the group STZ with glycemia between 120 and 300 mg/dL. At day 21 of pregnancy, blood samples were collected for glycemia and insulin determination, and placentas withdrawn for placental glycogen determination. The newborns (NB) were classified in small (SGA), appropriate (AGA) and large (LGA) for gestational age. RESULTS: Rats STZ presented higher glycemia at days 0 and 14 of pregnancy. At end of pregnancy, rats STZ showed higher proportion of NB SGA and LGA; reduced rate of NB AGA and unaltered glycemia, insulin and placental glycogen determinations. CONCLUSION: Mild diabetes altered the maternal glycemia in the early pregnancy, impairing future fetal development, but it caused no alteration on insulin and placental glycogen determination, confirming that this glycemic intensity was insufficient to change glycogen metabolism.