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Background: Pregnant women with mild gestational hyperglycemia present high risk for hypertension, obesity and hyperglycemia, and appeared to reproduce the model of metabolic syndrome in pregnancy, with hyperinsulinemia and insulin resistance. Our clinical studies showed that mild gestational hyperglycemia or gestational diabetes are related to similar adverse maternal and perinatal outcomes. Hyperglycemia and other factors associated with diabetes generate reactive oxygen species that increase DNA damage levels. The aim of this study was to evaluate oxidative DNA damage in lymphocytes of pregnant women with diabetes or mild gestational hyperglycemia. Methods: The study included 111 pregnant women distributed into three groups based on oral glucose tolerance test (OGTT) and glycemic profiles (GP), as follows: Normal OGTT and GP (control group); Normal OGTT and abnormal GP (mild gestational hyperglycemia group); Abnormal OGTT and GP (diabetic group). Maternal blood samples (5-10 mL) were collected and processed for determination of oxidative DNA damage by the comet assay, using Fpg and Endo III enzymes. Urine samples were also collected for determination of 8-OHdG concentrations by ELISA. Results: Subjects in the diabetes group presented increased amount of oxidized purines, while mild gestational hyperglycemia women presented with increased oxidized pyrimidines, compared to the control group. Conclusion: Gestational, overt diabetes and mild gestational hyperglycemia, were all related to increased oxidative DNA damage. Diabetic pregnant women showed increased level of oxidative DNA damage, perhaps mainly due to hyperglycemia. On the other hand, oxidative DNA damage detected in women with mild gestational hyperglycemia might be associated with repercussions from obesity, hypertension and/or insulin resistance. Interestingly, the type of DNA base affected seemed to be dependent on the glycemic profile or oxidative stress. [ABSTRACT FROM AUTHOR]

Background Pregnant women with mild gestational hyperglycemia present high risk for hypertension, obesity and hyperglycemia, and appeared to reproduce the model of metabolic syndrome in pregnancy, with hyperinsulinemia and insulin resistance. Our clinical studies showed that mild gestational hyperglycemia or gestational diabetes are related to similar adverse maternal and perinatal outcomes. Hyperglycemia and other factors associated with diabetes generate reactive oxygen species that increase DNA damage levels. The aim of this study was to evaluate oxidative DNA damage in lymphocytes of pregnant women with diabetes or mild gestational hyperglycemia. Methods The study included 111 pregnant women distributed into three groups based on oral glucose tolerance test (OGTT) and glycemic profiles (GP), as follows: Normal OGTT and GP (control group); Normal OGTT and abnormal GP (mild gestational hyperglycemia group); Abnormal OGTT and GP (diabetic group). Maternal blood samples (5-10 mL) were collected and processed for determination of oxidative DNA damage by the comet assay, using Fpg and Endo III enzymes. Urine samples were also collected for determination of 8-OHdG concentrations by ELISA. Results Subjects in the diabetes group presented increased amount of oxidized purines, while mild gestational hyperglycemia women presented with increased oxidized pyrimidines, compared to the control group. Conclusion Gestational, overt diabetes and mild gestational hyperglycemia, were all related to increased oxidative DNA damage. Diabetic pregnant women showed increased level of oxidative DNA damage, perhaps mainly due to hyperglycemia. On the other hand, oxidative DNA damage detected in women with mild gestational hyperglycemia might be associated with repercussions from obesity, hypertension and/or insulin resistance. Interestingly, the type of DNA base affected seemed to be dependent on the glycemic profile or oxidative stress. [ABSTRACT FROM AUTHOR]

Diabetes mellitus increases the risk of obstetric complications, morbidity, and infant mortality. Controlled nutritional therapy with micronutrients has been employed. However, the effect of calcium (Ca2+) supplementation on diabetic pregnancy is unclear. We aimed to evaluate whether diabetic rats supplemented with Ca2+ during pregnancy present better glucose tolerance, redox status, embryonic and fetal development, newborn weight, and the prooxidant and antioxidant balance of male and female pups. For this, newborn rats received the beta-cytotoxic drug streptozotocin for inducing diabetes on the day of birth. In adulthood, these rats were mated and treated with Ca2+ twice a day from day 0 to day 20 of pregnancy. On day 17, the pregnant rats were submitted to the oral glucose tolerance test (OGTT). At the end of pregnancy, they were anesthetized and killed to collect blood and pancreas samples. The uterine horns were exposed for an evaluation of maternal reproductive outcomes and embryofetal development, and the offspring's liver samples were collected for redox status measurement. Nondiabetic and diabetic rats supplemented with Ca2+ showed no influence on glucose tolerance, redox status, insulin synthesis, serum calcium levels, and embryofetal losses. The reduced rate of newborns classified as adequate for gestational age (AGA) and higher rates of LGA (large) and small (LGA) newborns and higher -SH and GSH-Px antioxidant activities in female pups were observed in diabetic dams, regardless of supplementation. Thus, maternal supplementation caused no improvement in glucose tolerance, oxidative stress biomarkers, embryofetal growth and development, and antioxidants in pups from diabetic mothers. [ABSTRACT FROM AUTHOR]

We used uncontrolled maternal diabetes as a model to provoke fetal growth restriction in the female in the first generation (F1) and to evaluate reproductive outcomes and the possible changes in metabolic systems during pregnancy, as well as the repercussions at birth in the second generation (F2). For this, nondiabetic and streptozotocin-induced severely diabetic Sprague-Dawley rats were mated to obtain female pups (F1), which were classified as adequate (AGA) or small (SGA) for gestational weight. Afterward, we composed two groups: F1 AGA from nondiabetic dams (Control) and F1 SGA from severely diabetic dams (Restricted) (n minimum = 10 animals/groups). At adulthood, these rats were submitted to the oral glucose tolerance test, mated, and at day 17 of pregnancy, blood samples were collected to determine glucose and insulin levels for assessment of insulin resistance. At the end of the pregnancy, the blood and liver samples were collected to evaluate redox status markers, and reproductive, fetal, and placental outcomes were analyzed. Maternal diabetes was responsible for increased SGA rates and a lower percentage of AGA fetuses (F1 generation). The restricted female pups from severely diabetic dams presented rapid neonatal catch-up growth, glucose intolerance, and insulin resistance status before and during pregnancy. At term pregnancy of F1 generation, oxidative stress status was observed in the maternal liver and blood samples. In addition, their offspring (F2 generation) had lower fetal weight and placental efficiency, regardless of gender, which caused fetal growth restriction and confirmed the fetal programming influence. [ABSTRACT FROM AUTHOR]

Maternal diabetes-mediated fetal programming is widely discussed, however, it is important to define the extent to which intrauterine hyperglycemia interferes with the health of female pups, along with determining whether these changes can be perpetuated across generations. This study aimed to evaluate the effects of maternal diabetes on fetal programming and the repercussions on the metabolism of pregnant and nonpregnant female pups. Diabetes status was induced (diabetic group—D) using streptozotocin (a beta cell cytotoxic drug) on the fifth postnatal day of female rats, while controls received a citrate buffer (Control—C). In adulthood, the rats were mated to obtain their female pups. At 90 days of age, half of the female pups were mated (preg) and the other half continued virgin (Npreg). Furthermore, they were distributed into four groups: OC/Npreg and OC/preg—female pups from control mothers; OD/Npreg and OD/preg—female pups from diabetic mothers. At 115 days of life and/or 17 days of pregnancy, the oral glucose tolerance test (OGTT) was performed with blood collection for insulin measurement. At 120 days of life and/or 21 days of pregnancy, the rats were anesthetized and euthanized to determine their blood oxidative stress status. The OD/Npreg group showed glucose intolerance during OGTT (p < 0.0001), while the OD/preg group showed increased insulin secretion during OGTT (p < 0.0001) and insulin resistance (IR; p = 0.0027). An increase in homeostatic model assessment β was shown in the pregnant groups, regardless of maternal diabetes (p < 0.0001). The OD/preg group presented increased thiobarbituric acid reactive substances (p < 0.0001) and –SH levels (p = 0.0005) and decreased superoxide dismutase activity (p = 0.0063). Additionally, small fetuses for gestational age (p < 0.0001) were found in these rats. In conclusion, exposure to maternal hyperglycemia compromises the glycemic metabolism of female pups before and during pregnancy and causes oxidative stress, IR, and impaired fetal growth during pregnancy. [ABSTRACT FROM AUTHOR]

Although several studies using peripheral blood samples suggest that DNA damage is caused by streptozotocin (STZ) per se, our hypothesis is that DNA damage is caused by STZ-induced glycemic changes. Thus, we aimed at evaluating DNA damage levels in peripheral blood samples from rats at different time points within the first 24 h after a single intravenous dose of STZ. Female Wistar rats (control, n = 8; STZ, n = 7) were administered a single STZ intravenous injection (40 mg/kg body weight). Blood samples were collected from the tail vein for genotoxicity analysis by comet assay and glycemia assessment before STZ administration (time point zero) and at 2, 4, 6, 8, 12, and 24 h afterward. At 2 h, there was initial hyperglycemia associated with STZ-induced glycogenolysis that caused an increase in leukocyte DNA damage levels. At 4 h, glycemic and DNA damage levels were normalized. However, at 6 and 8 h, we observed hypoglycemia concomitant with increased DNA damage levels. From 10 h onward up to 24 h, DNA damage persisted and hyperglycemia appeared. Thus, DNA damage increased soon after both hypoglycemia and hyperglycemia, which were not directly induced by STZ owing to its known short life. In conclusion, increased peripheral blood DNA damage levels within 24 h after STZ administration in rats are associated with abnormal glycemic levels and their complications rather than with STZ per se. [ABSTRACT FROM AUTHOR]

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. 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. 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. 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 (β)-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. [ABSTRACT FROM AUTHOR]

Abstract 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-β 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-β 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. [ABSTRACT FROM AUTHOR]

We conducted a meta-analysis to investigate whether diabetes induced by a high-fat diet (HFD) has the potential to alter the process of autophagy in the murine liver. A systematic literature search was performed with electronic databases (PubMed, EMBASE, Web of Science). Study design, population, intervention, outcome, and risk of bias were analyzed. Given the availability of studies, a quantitative meta-analysis including 23 studies was performed. The search found 5754 articles, with 48 matching the eligibility criteria, comprising of 1033 animals. The meta-analysis showed that diabetic murines fed with HFD presented an absence of p62 degradation (SMD 4.63, 95 % CI 2.02 to 7.24, p = 0.0005; I2 = 77 %), higher expression of p-mTOR/mTOR (SMD 5.20, 95 % CI 1.00 to 9.39, p = 0.01; I2 = 78 %), and a decreased p-AMPK/AMPK ratio (SMD -2.02, 95 % CI -3.96 to −0.09, p = 0.04; I2 = 85 %) when compared to nondiabetic murines. When associated with streptozotocin, the animals presented decreased ATG-7 and LC3-II. The meta-regression results showed a decrease in autophagy responses due to increased glycemic levels, fat content, and long-term exposure to HFD, and advanced animal age. The common and species-specific protein responses were also consistent with the inhibition of autophagy. The normal process of autophagy mechanisms in the liver is less competent after HFD consumption. The destabilization of (auto)phagolysosomes contributes to the perpetuation of diabetes, metabolic dysfunction-associated fatty liver disease, and cell death. [Display omitted] • Autophagy is an essential mechanism for the proper functionality of the liver. • The autophagy process in the liver is less competent after HFD consumption. • Diabetic rats and mice present impaired liver autophagy via higher mTOR and p62. • p-AMPK/AMPK levels decreased in the liver as age advanced. • The changes in protein expression of autophagy markers are species-specific. [ABSTRACT FROM AUTHOR]

Curatella americana L. is employed in popular medicine for treating diabetes. However, the understanding around its outcomes during pregnancy is unclear. To evaluate the phytochemical and hypoglycemic analysis of the C. americana extract and its maternal-fetal effect on diabetic rats. Diabetes was chemically induced 24 h after birth in Wistar female newborn rats. At adulthood, after diabetes status confirmation, the rats were mated and randomized into four experimental groups: Nondiabetic (Control): given water; Treated: given C. americana extract; Diabetic, and Treated Diabetic rats. The aqueous extract of C. americana leaves (300 mg/kg) was administered daily through oral route during pregnancy. Maternal toxicity and biochemical profile, reproductive outcomes, fetal development, and phenolic composition and biogenic amines in aqueous extract were analyzed. Phytochemical analysis revealed that the main phenolic components are 3-hydroxytyrosol, kaempferol, and quercetin, while tryptophan and putrescine derivatives were identified as the dominant amines. C. americana extract treatment improved the lipid profile, although no effect on hyperglycemic control in diabetic rats was observed. Maternal diabetes or C. americana extract caused embryo losses confirmed by the lower number of pre-embryos in early pregnancy and higher percentage of abnormal morphologically pre-embryos. C. americana extract previously caused premature pre-embryo fixation before implantation window in nondiabetic and diabetic mothers and intrauterine growth restriction in the fetuses of treated nondiabetic dams, complicating the embryo fetal development. These findings reinforce the caution of indiscriminate use of medicinal plants, especially during pregnancy. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to evaluate the effect of maternal mild hyperglycemia on maternal behavior, as well as the development, behavior, reproductive function, and glucose tolerance of the offspring. At birth, litters were assigned either to Control (subcutaneous (sc)-citrate buffer) or STZ groups (streptozotocin (STZ)-100mg/kg-sc.). On PND 90 both STZ-treated and Control female rats were mated. Glucose tolerance tests (GTT) and insulin tolerance tests (ITT) were performed during pregnancy. Pregnancy duration, litter size and sex ratio were assessed. Newborns were classified according to birth weight as small (SPA), adequate (APA), or large for pregnancy age (LPA). Maternal behavior was analyzed on PND 5 and 10. Offspring body weight, length, and anogenital distance were measured and general activity was assessed in the open field. Sexual behavior was tested in both male and female offspring. Levels of reproductive hormones and estrous cycle duration were evaluated in female offspring. Female offspring were mated and both a GTT and ITT performed during pregnancy. Neonatal STZ administration caused mild hyperglycemia during pregnancy and changed some aspects of maternal care. The hyperglycemic intrauterine milieu impaired physical development and increased immobility in the open field in the offspring although the latter effect appeared at different ages for males (adulthood) and females (infancy). There was no impairment in the sexual behavior of either male or female offspring. As adults, female offspring of STZ-treated mothers did not show glucose intolerance during pregnancy. Thus, offspring of female rats that show mild hyperglycemia in pregnancy have fewer behavioral and developmental impairments than previously reported in the offspring of severely diabetic dams suggesting that the degree of impairment is directly related to the mother glycemic intensity. [Copyright &y& Elsevier]