Protein restriction during peripubertal period impairs endothelial aortic function in adult male Wistar rats.

Protein restriction during early phases of body development, such as intrauterine life can favor the development of vascular disorders. However, it is not known if peripubertal protein restriction can favor vascular dysfunction in adulthood. The present study aimed to evaluated whether a protein restriction diet during peripubertal period favors endothelial dysfunction in adulthood. Male Wistar rats from postnatal day (PND) 30 until 60 received a diet with either 23% protein (CTR group) or with 4% protein (LP group). At PND 120, the thoracic aorta reactivity to phenylephrine, acetylcholine, and sodium nitroprusside was evaluated in the presence or absence of: endothelium, indomethacin, apocynin and tempol. The maximum response (Rmax) and pD2 (-log of the concentration of the drug that causes 50% of the Rmax) were calculated. The lipid peroxidation and catalase activity were also evaluated in the aorta. The data were analyzed by ANOVA (one or two-ways and Tukey's) or independent t-test; the results were expressed as mean ± S.E.M., p < 0.05. The Rmax to phenylephrine in aortic rings with endothelium were increased in LP rats when compared with the Rmax in CTR rats. Apocynin and tempol reduced Rmax to phenylephrine in LP aortic rings but not in CTR. The aortic response to the vasodilators was similar between the groups. Aortic catalase activity was lower and lipid peroxidation was greater in LP compared to CTR rats. Therefore, protein restriction during the peripubertal period causes endothelial dysfunction in adulthood through a mechanism related to oxidative stress.

Topiramate treatment during the peripubertal period does not alter aortic endothelial function in female Wistar rats.

AIMS: This study aimed to evaluate the short- and long-term adverse effects of blood pressure (BP), vascular endothelial function, and estrogen receptor (ERα and ERß) modulation on endothelial function in female Wistar rats treated with topiramate (TPM), an antiepileptic drug, during the peripubertal period. MATERIALS AND METHODS: Female Wistar rats were treated with TPM (41 mg/kg) or water (CTR group) by gavage from postnatal day (PND) 28 to 50 (peripubertal phase). At the end of the treatment, the TPM and CTR rats were divided into two groups and evaluated after 24 h or from PND 85 (adulthood). The rats were evaluated for: thoracic aorta reactivity to phenylephrine (Phenyl), acetylcholine (ACh), and sodium nitroprusside (SNP); aortic ring reactivity after ERα and ERß antagonism; and BP. KEY FINDINGS: It was observed that vascular response to Phenyl, ACh, and SNP was similar between TPM and CTR rats in the short- and long-term evaluations. In addition, the ER antagonism did not interfere with aortic contraction or relaxation in either TPM or CTR. SIGNIFICANCE: Taken together, the results show that TPM treatment during the peripubertal period does not alter aortic endothelial function and its estrogen modulation via classic ER in female Wistar rats, suggesting that TPM treatment in this period is safe for the vascular system.

Treatment with topiramate in rats during childhood causes testicular structural impairment at adulthood.

Topiramate (TOP) is a psychotropic drug prescribed for the treatment of epilepsy in children older than 2 years of age and for migraine prophylaxis in adolescents. There is evidence that TOP promotes negative effects on the reproductive system of male rats. This study aimed to evaluate the immediate and late treatment effects of TOP during childhood and adolescence on the male rat reproductive system. Two experimental groups received 41 mg/kg of TOP daily, by gavage, from postnatal day (PND) 16 to 28 (TOPc group) or from PND 28 to 50 (TOPa group). Control groups (CTRc group or CTRa group) received water daily. Half of the anim-als were evaluated 24 h after the end of treatment (PND 29 and PND 51, respectively) and the remainder were evaluated in adulthood (PND120). The following parameters were determined: anogenital distance, sperm evaluation, testis' histomorphometry and plasma testosterone concentration. At PND 120, the volume (CTRc:62.58 ± 2.13; TOPc: 54.54 ± 2.10*%, p = 0.018) and total length (CTRc: 25.48 ± 1.61; TOPc: 18.94 ± 2.41*, p = 0.035) of seminiferous tubules were decreased and the volume of interstitial tissue (CTRc:37.41 ± 2.13; TOPc: 45.45 ± 2.09*%, p = 0.018) and number of Leydig cells/testis (CTRc: 277.00 ± 36.70; TOPc: 400.20 ± 13.23*, p = 0.013) were increased in the TOPc group. The other parameters remained similar between the groups. Therefore, the present study contributes to our understanding that childhood treatment with TOP has an impact on the rat reproductive system in adulthood, suggesting that this period is more sensitive to TOP exposure than adolescence.

Gestational exposure to paracetamol in rats induces neurofunctional alterations in the progeny.

Paracetamol (PAR) is an over-the-counter medicine used as analgesic or antipyretic by 40-50% of the pregnant women in different countries. Epidemiologic studies have been associating maternal use of PAR with neurodevelopmental disruption and special attention has been given to its potential to increase the odds for neurodevelopmental disorders, such as attention-deficit hyperactive disorder and autism spectrum disorder. Population-based research do not allow the establishment of causal relationships because variable control is weak. We aimed to evaluate the potential of PAR to induce developmental neurotoxicity in rats. Pregnant Wistar rats were gavaged with PAR (350 mg/kg/day) or water from gestational day 6 until delivery. General toxicity endpoints included dams' body weight and food intake as well as pups' body weight until weaning. Behavioral evaluation occurred at post-natal days 10 (nest seeking test), 27 (behavioral stereotypy), 28 (three chamber sociability test and open field) and 29 (hot plate and elevated plus-maze). Moreover, lipid hidroperoxide (LOOH), reduced glutathione (GSH) and brain derived neurotrophic factor (BDNF) levels were quantified in prefrontal cortex and hippocampus of 22-days-old rats. Gestational exposure to PAR impaired nest seeking behavior, augmented apomorphine-induced behavioral stereotypy and decreased rostral grooming in the elevated plus maze. Exposed female pups presented elevated vertical exploration in the open field test. No alterations were observed in LOOH, GSH or BDNF levels in the prefrontal cortex or hippocampus. Exposure regimen did not affect general toxicity parameters or pups' behavior in the hot plate and sociability tests. These data suggest PAR as a developmental neurotoxicant. Observed alterations may be relevant for neurodevelopmental disorders.