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Background: Borolatonin is a potential therapeutic agent for some neuronal diseases such as Alzheimer's disease (AD). Its administration exerts ameliorative effects such as those induced by the equimolar administration of melatonin in behavioral tests on male rats and in neuronal immunohistochemistry assays. Objective: In this study, motivated by sex differences in neurobiology and the incidence of AD, the ability of borolatonin to induce changes in female rats was assessed. Methods: Effects of borolatonin were measured by the evaluation of both behavioral and immunohistopathologic approaches; additionally, its ability to limit amyloid toxicity was determined in vitro. Results: Surprisingly, behavioral changes were similar to those reported in male rats, but not those evaluated by immunoassays regarding neuronal survival; while pro‐brain‐derived neurotrophic factor (BDNF) immunoreactivity and the limitation of toxicity by amyloid in vitro were observed for the first time. Conclusion: Borolatonin administration induced changes in female rats. Differences induced by the administration of borolatonin or melatonin could be related to the differences in the production of steroid hormones in sex dependence. Further studies are required to clarify the possible mechanism and origin of differences in disturbed memory caused by the gonadectomy procedure between male and female rats. [ABSTRACT FROM AUTHOR]

Boronic acids form diester bonds with cis-hydroxyl groups in carbohydrates. The formation of these adducts could impair the physical and chemical properties of precursors, even their biological activity. Two carbohydrate derivatives from d-fructose and d-arabinose and phenylboronic acid were synthesized in a straightforward one-step procedure and chemically characterized via spectroscopy and X-ray diffraction crystallography. Additionally, an acute toxicity test was performed to determine their lethal dose 50 (LD50) values by using Lorke's method. Analytical chemistry assays confirmed the formation of adducts by the generation of diester bonds with the β-d-pyranose of carbohydrates, including signals corresponding to the formation of new bonds, such as the stretching of B–O bonds. NMR spectra yielded information about the stereoselectivity in the synthesis reaction: Just one signal was found in the range for the anomeric carbon in the 13C NMR spectra of both adducts. The acute toxicity tests showed that the LD50 value for both compounds was 1265 mg/kg, while the effective dose 50 (ED50) for sedation was 531 mg/kg. However, differences were found in the onset and lapse of sedation. For example, the arabinose derivative induced sedation for more than 48 h at 600 mg/kg, while the fructose derivative induced sedation for less than 6 h at the same dose without the death of the mice. Thus, we report for the first time two boron-containing carbohydrate derivatives inducing sedation after intraperitoneal administration. They are bioactive and highly safe agents. Further biological evaluation is desirable to explore their medical applications. [ABSTRACT FROM AUTHOR]

Acetaminophen is the most sold drug to treat pain. The TRPV1 channel is among its main targets. Due to its over-the-counter availability, its use is known as the main cause of acute liver failure induced by drugs. In addition, boron-containing compounds (BCC) have shown higher efficiency, potency, and affinity than their carbon counterparts. The present study explored the potential analgesic effect and hepatotoxicity of a BCC with a similar chemical structure to acetaminophen. Docking studies were carried out on the TRPV1 channel. In addition, a hot plate test was carried out with three doses of acetaminophen (APAP) and equimolar doses of 4-acetamidophenylboronic acid (4APB) in C57bl/6 mice. These same mice were submitted to a partial hepatectomy and continued compound administration, then they were sacrificed at day seven of treatment to analyze the liver histology and blood chemistry markers. From the in silico assays, it was observed that APAP and 4APB shared interactions with key residues, but 4APB showed a higher affinity on the orthosteric site. Mice administered with 4APB showed a higher latency time than those administered with their equimolar dose of APAP and the control group, with no motor pathway affected. The 4APB groups did not show an increase in hepatic enzyme activity while the APAP did show an increase in activity that was dose-dependent. Although all the experimental groups did show necrosis and inflammation, all APAP groups showed a greater cellular damage than their 4APB counterparts. In addition, the LD50 of 4APB is 409 mg/kg (against APAP-LD50 of 338 mg/kg). Thus, in the current evaluation, 4APB was a better analgesic and safer than APAP. [ABSTRACT FROM AUTHOR]

Levodopa is a cornerstone in Parkinson's disease treatment. Beneficial effects are mainly by binding on D2 receptors. Docking simulations of a set of compounds including well-known D2-ligands and a pool of Boron-Containing Compounds (BCC), particularly boroxazolidones with a tri/tetra-coordinated boron atom, were performed on the D2 Dopamine receptor (D2DR). Theoretical results yielded higher affinity of the compound DPBX, a Dopaboroxazolidone, than levodopa on D2DR. Essential interactions with residues in the third and sixth transmembrane domains of the D2DR appear to be crucial to induce and stabilize interactions in the active receptor state. Results from a motor performance evaluation of a murine model of Parkinson's disease agree with theoretical results, as DPBX showed similar efficacy to that of levodopa for diminishing MPTP-induced parkinsonism. This beneficial effect was disrupted with prior Risperidone (D2DR antagonist) administration, supporting the role of D2DR in the biological effect of DPBX. In addition, DPBX limited neuronal loss in substantia nigra in a similar manner to that of levodopa administration. [ABSTRACT FROM AUTHOR]

The potential of polyphenols for treating chronic-degenerative diseases (particularly neurodegenerative diseases) is attractive. However, the selection of the best polyphenol for each treatment, the mechanisms by which they act, and their efficacy are frequently discussed. In this review, the basics and the advances in the field, as well as suggestions for using natural and synthetic polyphenols alone or in a combinatorial strategy with stem cell assays, are compiled and discussed. Thus, stem cells exhibit several responses when polyphenols are added to their environment, which could provide us with knowledge for advancing the elucidation of the origin of neurodegeneration. But also, polyphenols are being included in the innovative strategies of novel therapies for treating neurodegenerative diseases as well as metabolic diseases related to neurodegeneration. In this regard, flavonoid compounds are suggested as the best natural polyphenols due to their several mechanisms for acting in ameliorative effects; but increasing reports are involving other polyphenols. Even if some facts limiting bioactivity prevent them from conventional use, some natural polyphenols and derivatives hold the promise for being improved compounds, judged by their induced effects. The current results suggest polyphenols as enhancers of stem cell therapy against the targeted diseases., Competing Interests: None

Oxidative stress (OS) is a key process in the development of many neurodegenerative diseases, memory disorders, and other pathological processes related to aging. Tibolone (TIB), a synthetic hormone used as a treatment for menopausal symptoms, decreases lipoperoxidation levels, prevents memory impairment and learning disability caused by ozone (O 3 ) exposure. However, it is not clear if TIB could prevent the increase in phosphorylation induced by oxidative stress of the microtubule-associated protein Tau. In this study, the effects of TIB at different times of administration on the phosphorylation of Tau, the activation of glycogen synthase kinase-3β (GSK3β), and the inactivation of Akt and phosphatases PP2A and PTEN induced by O 3 exposure were assessed in adult male Wistar rats. Rats were divided into 10 groups: control group (ozone-free air plus vehicle [C]), control + TIB group (ozone-free air plus TIB 1 mg/kg [C + TIB]); 7, 15, 30, and 60 days of ozone exposure groups [O 3 ] and 7, 15, 30, and 60 days of TIB 1 mg/kg before ozone exposure groups [O 3 + TIB]. The effects of O 3 exposure and TIB administration were assessed by western blot analysis of total and phosphorylated Tau, GSK3β, Akt, PP2A, and PTEN proteins and oxidative stress marker nitrotyrosine, and superoxide dismutase activity and lipid peroxidation of malondialdehyde by two different spectrophotometric methods (Marklund and TBARS, respectively). We observed that O 3 exposure increases Tau phosphorylation, which is correlated with decreased PP2A and PTEN protein levels, diminished Akt protein levels, and increased GSK3β protein levels in the hippocampus of adult male rats. The effects of O 3 exposure were prevented by the long-term treatment (over 15 days) with TIB. Malondialdehyde and nitrotyrosine levels increased from 15 to 60 days of exposure to O 3 in comparison to C group, and superoxide dismutase activity decreased. Furthermore, TIB administration limited the changes induced by O 3 exposure. Our results suggest a beneficial use of hormone replacement therapy with TIB to prevent neurodegeneration caused by O 3 exposure in rats., Competing Interests: Tibolone was used in this study. The authors declare that there are no competing interests in this study

Introduction: Oxidative stress increases brain lipid peroxidation, memory and motor deficits and progressive neurodegeneration. Tibolone, a treatment for menopausal symptoms, decreases lipid peroxidation levels and improves memory and learning., Aim: To study the effect of chronic administration of tibolone on lipid peroxidation, memory and motor deficits in ozone induced oxidative stress., Materials and Methods: 100 male Wistar adult rats were randomly divided into 10 experimental groups: control (C) was exposed to an airstream for 60 days; C + tibolone, airstream exposure plus 1 mg/kg of tibolone for 60 days; groups 3-6 were exposed to ozone for 7, 15, 30, and 60 days, and groups 7-10 received 1 mg/kg of tibolone treatment by oral gavage for 7, 15, 30 and 60 days and were then exposed to ozone. We determined the effect of tibolone on memory and motor activity. Hippocampus was processed to determine the content of 4-hydroxynonenal and nitrotyrosine by Western blot. Four animals were perfused and processed for analysis of neuronal death., Results: In the hippocampus, administration of 1 mg/kg of tibolone for 30 days prevented increased levels of lipid peroxidation and protein oxidation, whereas after 60 days prevented neuronal death in the CA3 region caused by exposure to ozone. Therefore, tibolone prevents cognitive deficits in short- and long-term memory on the passive avoidance task and prevents a decrease in exploratory behavior and an increase in freezing behavior., Conclusion: Our results indicate a possible neuroprotective role of tibolone as a useful treatment to prevent oxidative stress neurodegeneration.