Intrauterine exposure to metformin: Evaluation of endothelial and perivascular adipose tissue function in abdominal aorta of adult offspring

Topiramate treatment in Wistar rats during childhood induces sex-specific vascular dysfunction in adulthood

The present study determined whether treatment during childhood with topiramate (TPM), a new generation antiepileptic drug, results in altered aortic reactivity in adult male and female rats. We also sought to understand the role of endothelium-derived contractile factors in TPM-induced vascular dysfunction. Male and female Wistar rats were treated with TPM (41 mg/kg/day) or water (TPM vehicle) by gavage during childhood (postnatal day, 16-28). In adulthood, thoracic aorta reactivity to phenylephrine (phenyl), as well as aortic thickness and expression of cyclooxygenases (COX-1 and COX-2), NOX2, and p47^phox were evaluated. The aortic response to phenyl was increased in male and female rats from the TPM group when compared with the control group. In TPM male rats, the hyperreactivity to phenyl was abrogated by the inhibition of NADPH oxidase and COX-2, while in female rats, responses were restored only by inhibition of COX-2. In addition, TPM male rats presented aortic hypertrophy and increased expression of NOX-2 and p47phox, while TPM female rats showed increased COX-2 aortic expression. Taken together, for the first-time, the present study provides evidence that treatment with TPM during childhood causes vascular dysfunction in adulthood, and that the mechanism underlying the vascular effects of TPM is sex-specific.

Intrauterine and Lactational Exposure to Paracetamol: Cardiometabolic Evaluation in Adult Female and Male Offspring

ABSTRACT

Paracetamol (PAR) is the most common over-the-counter drug recommended by physicians for treatment of pain and fever during gestation. This drug is not teratogenic, being considered safe for fetus; however, PAR crosses the blood-placental barrier. Considering that, the present study aimed to evaluate the vascular and metabolic safety of PAR exposure during intrauterine and neonatal development in adult male and female-exposed offspring. Wistar female rats were gavaged, with PAR (350 mg/kg/d), from gestational day 6-21 or from gestational day 6 until postnatal day 21. Control dams received water by gavage at the same periods. The male and female offspring were evaluated at adulthood (80 days of life). The thoracic aorta reactivity to acetylcholine, sodium nitroprusside, and phenylephrine was evaluated in male and female adult offspring. It was observed that aortic relaxation was similar between the PAR and control offspring. In addition, the contraction to phenylephrine was similar between the groups. Further, the insulin sensitivity, adipose tissue deposition and blood pressure were not different between PAR and control adult offspring. These results suggest that the protocol of PAR exposure used in the present study did not program vascular and metabolic alterations that would contribute to the development of cardiometabolic diseases in adult life, being safe for the exposed offspring.

The effects of metformin treatment on the ovaries and uterus of offspring

OBJECTIVE

The aim of this study is to investigate the effects of metformin treatment at different dosage levels on the ovaries and uteruses of rat offspring in the course of the intrauterine period.

METHODS

 Saline, metformin (100 mg/kg/day), and metformin (200 mg/kg/day) were administered via oral gavage between the 6th and 15th days of gestation to the 9 pregnant rats (n = 3/group). After birth, 5 female offspring were separated from each group and perfused on the 60th day of postnatal development. The cortex and medulla volumes of the ovaries, the thicknesses of epithelium and endometrium of the uteruses and the total oocyte number density were estimated. In addition, the estradiol levels in blood samples were measured by the ELISA method.

RESULTS

There were no statistically significant differences among the groups regarding the number of oocytes, the volumes of ovarian cortex, medulla, primary and secondary follicles (p > .05). In comparison with the control group, the volume of the tertiary follicle, the thickness of the uterus epithelium, and the estradiol level were significantly decreased in Metformin 200 group (p < .05).

CONCLUSIONS

The gestational exposure to high dose metformin may result in decreased estradiol production and subsequently decreased endometrial thickness of offspring rats.

Can maternal treatment with metformin during gestation and lactation cause metabolic and cardiovascular disorders in rat offspring?

Objective: The aim was to evaluate if maternal treatment with metformin (MET) during pregnancy and lactation could be safe for metabolic and cardiovascular parameters of adult male and female offspring.Materials and methods: Wistar female rats were treated with MET (293 mg/kg/d) or tap water, by gavage during gestation (METG or CTRG) or gestation and lactation (METGL or CTRGL).Results: At 75 days of life, male and female MET offspring presented similar blood pressure when compared with their CTR. The heart rate of female METGL was higher than in the CTRGL. The insulin sensitivity, basal glycaemia, body weight, Lee index of obesity, plasmatic concentration of triglycerides, total cholesterol and fat acid of male and female MET were similar to CTR groups. Lower fat pad deposition was observed in female METG and METGL.Conclusion: MET exposure during gestational and lactation does not program cardiovascular and metabolic alterations in adult offspring life.

Metformin decreases hyaluronan synthesis by vascular smooth muscle cells

Metformin is the first-line drug in the treatment of type 2 diabetes worldwide based on its effectiveness and cardiovascular safety. Currently metformin is increasingly used during pregnancy in women with gestational diabetes mellitus, even if the long-term effects of metformin on offspring are not exactly known. We have previously shown that high glucose concentration increases hyaluronan (HA) production of cultured human vascular smooth muscle cells (VSMC) via stimulating the expression of hyaluronan synthase 2 (HAS2). This offers a potential mechanism whereby hyperglycemia leads to vascular macroangiopathy. In this study, we examined whether gestational metformin use affects HA content in the aortic wall of mouse offspring in vivo. We also examined the effect of metformin on HA synthesis by cultured human VSMCs in vitro. We found that gestational metformin use significantly decreased HA content in the intima-media of mouse offspring aortas. In accordance with this, the synthesis of HA by VSMCs was also significantly decreased in response to treatment with metformin. This decrease in HA synthesis was shown to be due to the reduction of both the expression of HAS2 and the amount of HAS substrates, particularly UDP-N-acetylglucosamine. As shown here, gestational metformin use is capable to program reduced HA content in the vascular wall of the offspring strongly supporting the idea, that metformin possesses long-term vasculoprotective effects.

Reproductive evaluations in female rat offspring exposed to metformin during intrauterine and intrauterine/lactational periods

Metformin (MET) is a widely-used drug for the treatment of type 2 diabetes mellitus and gestational diabetes. It is known that metformin crosses the placenta and can to be transferred through milk. In vitro studies show that MET decreases gonadotropin-releasing hormone and gonadotropins release in rat neurons, and decreases progesterone and estradiol in rat granulosa cells and androstenedione synthesis in human theca cells. This study evaluated whether MET maternal exposure might interfere with reproductive parameters of female offspring. Wistar female rats were treated with MET 293 mg/kg/day, by gavage, from gestational day (GD) 0 to GD 21 (METG) or GD 0 until lactation day (LD) 21 (METGL). Controls groups received water. An increase in plasmatic estradiol levels was observed during the estrus stage in the METGL group. This result suggests that exposure to MET during gestational and lactational periods might be related to programming in theca and/or granulosa cells during development.