Involvement of BDNF/TrkB signaling in the effect of diphenyl diselenide on motor function in a Parkinson's disease rat model

Parkinson's disease is a progressive neurodegenerative disorder characterized by degeneration of nigrostriatal dopaminergic neurons. Diphenyl diselenide [(PhSe)₂] is a compound with pharmacological proprieties, such as antidepressant and neuroprotective. Therefore, this study investigated whether (PhSe)₂ reverses motor impairment and neurochemical alterations in a model of Parkinson's disease induced by 6-hydroxydopamine (6-OHDA) in rats. For this, male Wistar rats received 20μg/3μl of 6-OHDA or vehicle into the right striatum. Three weeks later, animals were subjected to rotational behavioral test induced by D-amphetamine and randomly divided into four groups: Sham; (PhSe)₂; 6-OHDA and 6-OHDA+(PhSe)₂. The rats received (PhSe)₂ (1mg/kg/day; i.g.) or vehicle (canola oil) during 30 days. After treatment, behavioral tests were performed in order to evaluate the motor function and the ipsilateral striatal tissue was collected for immunoblotting assay. (PhSe)₂ treatment restored the normal motor behavior of 6-OHDA-infused rats in the cylinder, stepping and bridge tests, but not in the rotarod test. The 6-OHDA infusion and/or (PhSe)₂ treatment did not alter the muscle strength and spontaneous locomotion in the forelimb support and open-field tests, respectively. Additionally, striatal brain-derived neurotrophic factor (BDNF), proBDNF and tyrosine hydroxylase (TH) levels of 6-OHDA-lesioned rats were decreased, while the tropomyosin-related kinase B (TrkB) levels were increased. (PhSe)₂ treatment restored striatal proBDNF, TrkB and TH levels. Thus, (PhSe)₂ treatment reversed some motor impairment and TH levels in a 6-OHDA model of Parkinson's disease in rats, demonstrating a potential neurorestorative role. Additionally, the BDNF/TrkB signaling recovery can be involved in its neurorestorative effect.

Repeated malathion exposure induces behavioral impairment and AChE activity inhibition in brains of rat pups

The present study evaluated if repeated malathion administration would cause behavioral impairment in rat pups. Na+K+ ATPase and acetylcholinesterase (AChE) activities were investigated in brains of rat pups. Malathion was administered (100 or 200 mg/kg) orally (p.o.), once a day for four consecutive days. Rat pups were submitted to behavioral tests on the 5th day, 24 h after the last malathion administration. Malathion at the dose of 200 mg/kg caused a significant increase in the negative geotaxis latency and a decrease in the rotarod latency of rat pups. Rat pups exposed to malathion at both doses showed a significant decrease in the forelimb support latency and an inhibition of brain AChE activity. Repeated exposure of rat pups to malathion caused a decrease in motor coordination, vestibular function and muscular strength/coordination. The brain activity of AChE is involved in the behavioral alterations caused by malathion in rat pups.

Diphenyl diselenide reduces mechanical and thermal nociceptive behavioral responses after unilateral intrastriatal administration of 6-hydroxydopamine in rats

Parkinson's disease (PD) patients, in addition to motor dysfunction, also present alterations in pain sensation. The present study characterized the antinociceptive effects of diphenyl diselenide ((PhSe)2) in a model of nociception induced by unilateral, intrastriatal 6-hydroxydopamine (6-OHDA) injection in rats. Male adult Wistar rats received 20 μg/3 μl of 6-OHDA (in saline solution containing 0.02 % of ascorbic acid) or 3 μl of vehicle into the right striatum (1.0 mm anterior, 3.0 mm lateral, and 5.0 mm ventral-with respect to the bregma). Thirty days after injection, rats received (PhSe)2 intragastrically at a dose of 10 mg/kg 1 h before behavioral tests (von Frey hairs, hot plate, tail immersion, formalin, and open field). Our results demonstrated that 6-OHDA injection to rats augmented the response frequency of von Frey hairs (VHF) stimulation, besides reducing the thermal withdrawal latency in the hot plate test. Importantly, the (PhSe)2 treatment decreased the mechanical allodynia measured by the response frequency of VHF stimulation and diminished the thermal nociception in the hot plate test in 6-OHDA-injected rats. In conclusion, these results revealed that a single oral administration of (PhSe)2 1 h prior to the accomplishment of the behavioral tests was effective to attenuate the increased mechanical and thermal nociception caused by a single intrastriatal 6-OHDA injection to rats. Furthermore, other clarifying studies are warranted to improve the evidence bases for future clinical use of (PhSe)2 as a new alternative therapy for the treatment of painful symptoms associated to PD.

Hydroxyl containing seleno-imine compound exhibits improved anti-oxidant potential and does not inhibit thiol-containing enzymes

Design and synthesis of organoselenium compounds with high thiol peroxidase (TPx) and low thiol oxidase (TOx) activities have been a difficult task and remains a synthetic-activity relationship dilemma. In this regard we are reporting for the first time a detail experimental data (both in vitro and in vivo) about the anti-oxidant and toxicological profile of an Imine (-N) containing organoselenium compound (Compound A). The TPx activity of Compound A was significantly higher than diphenyl diselenide (DPDS). Both Compound A and DPDS protected sodium nitropruside (SNP) induced thiobarbituric acid reactive species (TBARS) production in rats tissue homogenate with significantly higher activity observed for Compound A than DPDS (p<0.05). The Compound A also exhibited strong antioxidant activity in the DPPH and ABTS radical scavenging assays. This study reveals that an imine group close to selenium atom drastically enhances the catalytic activities in the aromatic thiol (PhSH) assay systems. The oxidation of biologically significant thiols reflects the toxicity of the compounds. However, the present data showed that treatment with Compound A at 0, 10, 25 or 50mg/kg was not associated with mortality or body weight loss. Similarly it did not inhibit α-ALA-D and Na(+1)/K(+1) ATPase (sulfhydryl group containing enzymes) activities after acute oral treatment; rather it enhanced non-protein thiols (NPSH) concentration. The Compound A did not cause any oxidative stress as measured by TBARS production in rat's tissue preparation. Our data also indicate that exposure to Compound A did not affect plasma transaminase activities or levels of urea and creatinine in rats. Ascorbic acid is always considered a marker of oxidative stress and the reduction of its content may indicate an increase in oxidative stress. Treatment with Compound A did not alter Ascorbic acid levels in rats. The conducted in vitro and in vivo tests show the versatile therapeutic potential of this compound in the area of free radical induced damages, will undoubtedly enhance our understanding of the mechanism of model compounds and may ultimately yield insights that result in improved GPx mimics.

Effects of diphenyl diselenide on lipid profile and hepatic oxidative stress parameters in ovariectomized female rats

Objectives

Ovarian hormone decline after menopause is linked to many pathophysiological reactions. Female rats submitted to ovariectomy are employed as a model of post-menopausal condition. This study investigated the effects of diphenyl diselenide (PhSe)2 on body weight gain, intra-abdominal fat deposition, plasma lipid profile and hepatic oxidative stress in ovariectomized rats.

Methods

Female adult Wistar rats were ovariectomized (OVX rats) or sham-operated and divided into four groups: (i) sham-operated, (ii) (PhSe)2, (iii) OVX and (iv) OVX + (PhSe)2. (PhSe)2 (5 mg/kg; 5 ml/kg, p.o.) was administered once a day for 30 days to groups (ii) and (iv). After that, rats were anaesthetized for blood sample gathering and submitted to euthanasia.

Key findings

(PhSe)2 (5 mg/kg) was effective in preventing the rise in body weight gain and intra-abdominal fat deposition induced in OVX rats. Although (PhSe)2 was not effective in avoiding the increase in plasma total cholesterol and non-HDL levels induced in OVX rats, (PhSe)2 reduced plasma triglycerides and augmented HDL levels in OVX rats. (PhSe)2 also increased hepatic ascorbic acid levels, reduced glutathione content, glutathione S-transferase activity and restored catalase activity in liver of OVX rats.

Conclusions

These findings suggest that (PhSe)2 could be a promising alternative to minimize menopause related symptoms.

Cognitive effects of diphenyl diselenide and estradiol treatments in ovariectomized mice

This study investigated the effects of co-administration of diphenyl diselenide [(PhSe)(2)] and 17β-estradiol (E(2)) on spatial reference, recognition, and working memories in ovariectomized (OVX) female mice. Sixty-day-old female adult Swiss mice were submitted to ovariectomy. From the 30th until 32nd day after ovariectomy, different doses of (PhSe)(2) (0.5-10mg/kg p.o.) were administrated to OVX mice 30min before each training of Morris Water Maze (MWM) test in order to find the highest subeffective dose for this drug. After that, OVX mice were divided into four groups: Oil, (PhSe)(2), E(2), and (PhSe)(2)+E(2). (PhSe)(2) (0.5mg/kg) and E(2) (0.1mg/kg) were administered to OVX mice from 30th to 32nd day after surgery, 30min before the training phases of behavioral tests (Open Field, MWM, Object Recognition, and T-maze). Our results demonstrated that 0.5mg/kg (PhSe)(2) plus 0.1mg/kg E(2) combined treatment improved spatial memory in the MWM test. By contrast, this same co-administration therapy was not effective in ameliorating neither delayed spontaneous alternation in the T-maze test nor object recognition memory deficits in OVX mice, although the dose of 0.5mg/kg (PhSe)(2) enhanced per se the object recognition memory in OVX mice. In conclusion, the current behavioral data suggest that a combination of (PhSe)(2) plus E(2) treatment seems to be a promising alternative to treat the cognitive decline related to menopause. Further studies should be conducted in order to determine an effective dose for (PhSe)(2) plus E(2) therapy on Object Recognition and T-maze tests.

The hypolipidemic action of a diet supplemented with p,p'-methoxyl-diphenyl diselenide is not directly related to its antioxidant property

The present study investigated whether a p,p'-methoxyl-diphenyl diselenide (MeOPhSe)2-supplemented diet causes toxicity in rats. A second aim of this study was to determine whether a 10 ppm (MeOPhSe)2-supplemented diet has hypolipidemic effect on Triton WR-1339-induced hyperlipidemia in rats. To rule out the antioxidant property of (MeOPhSe)2 in its hypolipidemic action, parameters of oxidative stress were carried out. Wistar rats were fed with 3, 10, or 30 ppm of (MeOPhSe)2-supplemented diet for 30 days. None of (MeOPhSe)2-supplemented diets caused alteration in general parameters of toxicity and lipid profile of rats. The hypolipidemic effect of 10 ppm of (MeOPhSe)2-supplemented diet on rats treated with Triton WR-1339 (400 mg/kg, intraperitoneal) was investigated. The (MeOPhSe)2-supplemented diet partially protected against the levels of total cholesterol (TC) and non-HDL-C and reduced the atherogenic index (AI) increased by Triton WR-1339 in rats. A positive correlation between TC and triglyceride levels (r = 0.679) and non-HDL-C levels (r = 0.929) and AI (r = 0.889) was demonstrated. Triton WR-1339 altered parameters of oxidative stress in livers of rats but (MeOPhSe)2-supplemented diet did not protect against these alterations. The results demonstrated that the hypolipidemic action of (MeOPhSe)2-supplemented diet is not directly related to its antioxidant property and devoid of systemic toxicity in rats at the parameters analyzed.

Alcohol consumption during pregnancy by women from southern Brazil: a cross-sectional study

BACKGROUND

Some maternal characteristics are related to alcohol intake during pregnancy, which irreversibly compromises the maternal-fetal binomial integrity.

OBJECTIVES

To identify the frequency, impact, and factors associated with alcohol consumption during pregnancy.

DESIGN AND SETTING

A cross-sectional study was performed at the Hospital Materno Infantil Presidente Vargas (HMIPV) in Porto Alegre/RS between March and December 2016.

METHODS

A structured questionnaire was administered along with a medical records review. They refer to the maternal sociodemographic and gestational status, alcohol consumption patterns, and characteristics of the fetus/newborn. In the statistical analysis, P values < 0.05 were considered significant.

RESULTS

The frequency of alcohol intake was 37.3%; this was characterized by the consumption of fermented beverages (89.3%), especially during the first trimester (79.6%). Risky consumption (high and/or early) occurred for 30.2% of participants. Risk factors associated with maternal alcohol consumption during pregnancy were tobacco use (P < 0.001) and abortion attempt (P = 0.023). Living with a partner (P = 0.002) and planning pregnancy (P = 0.009) were protective factors. Risky consumption was related to all of the aforementioned variables as well as threatened abortion (P = 0.023).

CONCLUSIONS

Alcohol intake during pregnancy is common and affects nearly one-third of pregnant women. Knowledge of the population at risk and protective factors is essential for the development of campaigns that seek to reduce consumption and, therefore, its consequences for the mother and fetus.

Growth hormone and gonadotropin association: A case report of full-term pregnancy in a patient with panhypopituitarism

Hypopituitarism is the inability of the anterior pituitary gland to properly supply the hormone levels. When this disease affects all the hormones produced by the anterior pituitary, it is called panhypopituitarism (PHP). Since pituitary-derived hormones directly influence fertility, often the assisted reproduction techniques are the only option to PHP women have a full-term pregnancy. However, not all patients diagnosed with PHP properly respond to ovulation induction. Thus, a poor response may indicate decreased ovarian reserve or reflect a deficiency in other key components of ovarian function. Here we presented a rare case of a 24-year-old woman diagnosed with PHP and poor response to previous gonadotropin therapy. In our protocol the patient received first growth hormone (GH) replacement for 5 months before starting gonadotropins. When the serum IGF-I (insulin grow factor-I) level normalized, she started ovulation induction with 225 IU/day of human menopausal gonadotropin (hMG). After the ninth day of the cycle, ultrasounds were performed every 2 days to control follicular growth. The puncture of the follicles was performed on the twentieth day of the cycle and a surprising number of 13 oocytes were collected. The oocytes were fertilized by the classical IVF method, resulting in 11 D3 embryos, of which 2 were freshly transferred. Beta hCG hormone levels were determined, and a single fetus pregnancy was confirmed. The birth was by cesarean section at 38 weeks of gestation. Therefore, we conclude that GH/gonadotropin association in ovarian stimulation may improve the follicular recruitment in PHP patients.