Evaluation of blood pressure and aortic elasticity of offspring of diabetic Wistar rats who have consumed flaxseed oil during pregnancy and lactation.

OBJECTIVE: This study aimed to investigate whether maternal use of flaxseed oil has effects on blood pressure and aorta elastic fibre in female offspring of diabetic mothers. METHODS: Diabetes was induced into the rats (n = 18) by a high-fat diet and streptozotocin. After diabetes confirmation, rats were mated, and after pregnancy was confirmed, they were allocated into three groups: control group (CG); high-fat group (HFG); and flaxseed oil group (FOG). At weaning, female offspring (n = 6/group) received standard chow diet and were euthanized at 100 days of life. The following blood pressure and the percentage of the aortic elastic fibre were analysed. RESULTS: HFG showed higher blood pressure, and the use of flaxseed oil avoided this condition in FOG (p < 0.001) and increased the percentage of the aortic elastic fibre (p < 0.022). CONCLUSIONS: Flaxseed oil reduced the damage caused by maternal hyperglycaemia, promoting normal blood pressure and elasticity of the aorta in female offspring.

Diabetic complications in pregnancy: is resveratrol a solution?

Diabetes is a metabolic disorder that, during pregnancy, may affect fetal development. Fetal outcome depends on the type of diabetes present, the concentration of blood glucose and the extent of fetal exposure to elevated or frequently fluctuating glucose concentrations. The result of some diabetic pregnancies will be embryonic developmental abnormalities, a condition referred to as diabetic embryopathy. Tight glycemic control in type 1 diabetes during pregnancy using insulin therapy together with folic acid supplementation are partially able to prevent diabetic embryopathy; however, the protection is not complete and additional interventions are needed. Resveratrol, a polyphenol found largely in the skins of red grapes, is known to have antidiabetic action and is in clinical trials for the treatment of diabetes, insulin resistance, obesity and metabolic syndrome. Studies of resveratrol in a rodent model of diabetic embryopathy reveal that it significantly improves the embryonic outcome in terms of diminishing developmental abnormalities. Improvements in maternal and embryonic outcomes observed in rodent models may arise from resveratrol's antioxidative potential, antidiabetic action and antidyslipidemic nature. Whether resveratrol will have similar actions in human diabetic pregnancy is unknown. Here, we review the potential therapeutic use of resveratrol in diabetes and diabetic pregnancy.

Dietary treatments enriched in olive and safflower oils regulate seric and placental matrix metalloproteinases in maternal diabetes.

OBJECTIVES: Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in placental development and function, although related to the pro-inflammatory environment when produced in excess. Previous studies have identified MMP-2 and MMP-9 overactivities in the placenta from diabetic rats. In this study, we aimed to determine whether diets supplemented with olive and safflower oil, enriched in natural PPAR ligands, are able to regulate MMP-2 and MMP-9 activities in the placenta and serum from diabetic rats. STUDY DESIGN: Diabetes was induced in rat neonates by streptozotocin administration (90mg/kg s.c.). Control and diabetic rats were fed with 6% olive oil- or 6% safflower oil-supplemented diets from days 0.5-13.5 of gestation. MAIN OUTCOME MEASURES: On day 13.5 of gestation, placentas and sera were isolated for further determination of matrix metalloproteinases (MMPs) 2 and 9 activities by zymography. Placental MMP-2 and MMP-9 protein concentration and immunolocalization were also determined. RESULTS: Sera from diabetic pregnant animals showed MMP-2 and MMP-9 overactivities when compared to controls. Serum MMP-9 activity was significantly decreased when the diabetic animals received the olive and safflower oil dietary treatments. Placentas from diabetic rats showed increased MMP-2 and MMP-9 activities and protein concentrations, and both were decreased when diabetic rats received the olive and safflower dietary treatments. CONCLUSIONS: This study demonstrates that both olive and safflower oil-supplemented diets were able to prevent MMPs overactivities in the placenta from diabetic rats, and that these beneficial effects are reflected in rat sera.

Evaluation of glycemic and lipid profile of offspring of diabetic Wistar rats treated with Malpighia emarginata juice.

Knowing that maternal diabetes is related to hyperglycemia and fetal hyperinsulinemia, which affect the lipid metabolism, the aim of this study was to evaluate the effects of Malpighia emarginata (acerola) juice on the glycemic and lipid profile of offspring of diabetic and nondiabetic Wistar rats. The adult offspring of non-diabetic dams and of dams with severe streptozotocin-induced diabetes were divided into groups: G1, offspring (of control dams) treated with water, G2, offspring (of diabetic dams) treated with water, G3, male offspring (of control dams) treated with acerola juice, and G4, male offspring (of diabetic dams) treated with acerola juice. The offspring of diabetic dams treated with acerola juice showed significantly decreased levels of glucose, cholesterol, triglycerides, and increased HDL-c. The use of acerola juice is a potential strategy to aid in the prevention of DM and dyslipidemia and its complications or to act as an auxiliary in the treatment of these diseases.

Folic acid prevents congenital malformations in the offspring of diabetic mice.

It is well known that maternal diabetes causes various congenital malformations. Although there are many reports that folic acid (FA) administration in pregnancy reduces the risk of birth defects including neural tube defects (NTDs), a precise analysis on the preventive effect of FA against diabetic embryopathy has not been done yet. In this study, we analyzed the preventive effects of FA on congenital malformations including NTDs, cardiovascular, and skeletal malformations using a diabetic mouse model. Female mice were rendered hyperglycemic by streptozotocin and then mated. Pregnant diabetic mice were treated daily with FA (3 mg/kg body weight) or saline between gestational days (GD) 6 and 10. On GD 18, fetuses were examined for congenital malformations. FA did not affect plasma glucose levels. In the DM control group, the incidence of NTDs, cardiovascular, and skeletal malformations was 28.4%, 28.5%, and 29.7%, respectively. In the FA-treated group, the corresponding proportions reduced to 6.0%, 2.5% and 12.5%, respectively. A whole-mount TUNEL revealed an increased apoptosis in the hindbrain region of embryos from DM control group on day 9.5, and the apoptosis was decreased by FA treatment. Maternal plasma homocysteine levels on GD 9.5 were significantly lowered in DM control group compared with those in non-DM group, and FA treatment did not show a significant effect. These results indicate that FA is effective for the prevention of various diabetic embryopathy including NTDs, cardiovascular, and skeletal malformations, and suggested that this effect is independent from homocysteine metabolism and possibly mediated by decreasing the abnormal apoptosis during organogenesis.

The influence of L-arginine on blood pressure, vascular nitric oxide and renal morphometry in the offspring from diabetic mothers.

The present study was designed to evaluate the effects of L-arginine (L-arg) supplementation on blood pressure, vascular nitric oxide content, and renal morphometry in the adult offspring from diabetic mothers. Diabetes mellitus was induced in female rats with a single dose of streptozotocin (50 mg/kg), before mating. The offspring was divided into four groups: group C (controls); group DO (diabetic offspring); group CA (controls receiving 2% L-arg solution dissolved in 2% sucrose in the drinking water) and group DA (DO receiving the L-arg solution). Oral supplementation began after weaning and continued until the end of the experiments. In DO, hypertension was observed, from 3 mo on. In DA, pressure levels were not different from C and CA. In 6-mo-old animals, basal NO production (assessed by DAF-2) was significantly depressed in DO in comparison to controls. The NO production was significantly increased after stimulation with Ach or BK in all groups, the increase being greater in control than in DO rats. L-arg was able to improve the NO production and to prevent the glomerular hypertrophy in the DO. Our data suggest that the bioavailability of NO is reduced in the DO, because L-arg corrected both the hypertension and glomerular hypertrophy.

Folic acid supplementation affects ROS scavenging enzymes, enhances Vegf-A, and diminishes apoptotic state in yolk sacs of embryos of diabetic rats.

We aimed to investigate the extent to which maternal diabetes with or without folic acid (FA) supplementation affects mRNA levels and protein distribution of ROS scavenging enzymes, vascular endothelial growth factor-A (Vegf-A), folate binding protein-1 (Folbp-1), and apoptosis-associated proteins in the yolk sacs of rat embryos on gestational days 10 and 11. Commencing at conception and throughout pregnancy, half of the streptozotocin-diabetic and half of the control rats received daily FA injections. Maternal diabetes impaired vascular morphology and decreased CuZnSOD and GPX-1 gene expression in yolk sacs. Maternal diabetes also increased the levels of CuZnSOD protein, increased the Bax/Bcl-2 protein ratio and decreased Vegf-A protein distribution. FA treatment normalized vascular morphology, decreased mRNA levels of all three SOD isoforms and increased Vegf-A mRNA levels, rectified CuZnSOD protein distribution and Bax/Bcl-2 ratio. A teratogenic diabetic environment produces a state of vasculopathy, oxidative stress, and mild apoptosis in the yolk sac. FA administration normalizes vascular morphology, diminishes apoptotic rate, and increases Vegf-A gene expression and protein distribution in the yolk sac of diabetic rats.

Maternal antioxidant treatments prevent diabetes-induced alterations of mitochondrial morphology in rat embryos.

Previous studies have suggested that production of reactive oxygen species by embryonic mitochondria may have a role in the induction of both high-amplitude mitochondrial swelling and embryonic dysmorphogenesis in diabetic pregnancy. The present study analyzed the relationships between a putative metabolite-induced production of free oxygen radicals, mitochondrial lipid peroxidation, and high-amplitude mitochondrial swelling in embryos during organogenesis. For studies in vitro, day 9 embryos of normal rats were cultured for 48 h with a high concentration of glucose in the absence or presence of alpha-cyano-4-hydroxycinnamic acid (CHC), a mitochondrial pyruvate transport inhibitor. The morphology of mitochondria in the neuroepithelium of the embryos was studied with the aid of transmission electron microscopy. For studies in vivo, normal and diabetic pregnant rats were fed a diet supplemented with the antioxidants alpha-tocopherol (vitamin E) or 2,6-di-tert-butyl-4-methylphenol (BHT), and the ultrastructure of mitochondria in the embryonic neuroepithelium and in the visceral yolk sac was investigated on gestational day 11. Exposure to a high concentration of glucose in vitro or to maternal diabetes in vivo induced high-amplitude swelling of mitochondria in the neuroepithelium of the embryos. The swelling of mitochondria was prevented by addition of CHC to the culture media or by maternal ingestion of antioxidant-supplemented food. In diabetic pregnancy, embryonic mitochondria during organogenesis produce free oxygen radicals that cause mitochondrial lipid peroxidation and swelling and furthermore embryonic dysmorphogenesis. Dietary supplementation with antioxidants to the mother may prevent embryonic malformations in diabetic pregnancy by inhibition of mitochondrial dysfunction.