Synthesis and Evaluation of Antioxidant, Anti-Edematogenic and Antinociceptive Properties of Selenium-Sulfa Compounds.

Herein we describe results for the synthesis and synthetic application of 4-amino-3-(arylselenyl)benzenesulfonamides, and preliminary evaluation of antioxidant, anti-edematogenic and antinociceptive properties. This class of compounds was synthesized in good yields by a reaction of commercially available sulfanilamide and diorganyl diselenides in the presence of 10 mol% of I2 . Furthermore, the synthesized compound 4-amino-3-(phenylselenyl)benzenesulfonamide (3 a) was evaluated on complete Freund's adjuvant (CFA)-induced acute inflammatory pain. Dose- and time-response curves of antinociceptive effect of compound 3 a were performed using this experimental model. Also, the effect of compound 3 a was monitored in a hot-plate test to evaluate the acute non-inflammatory antinociception. The open-field test was performed to evaluate the locomotor and exploratory behaviors of mice. Oxidative stress markers, such as glutathione peroxidase activity; reactive species, non-protein thiols, and lipid peroxidation levels were performed to investigate the antioxidant action of compound 3 a. Our findings suggest that the antioxidant effect of compound 3 a may contribute to reducing the nociception and suppress the signaling pathways of inflammation on the local injury induced by CFA. Thus, compound 3 a reduced the paw edema as well as the hyperalgesic behavior in mice, being a promising therapeutic agent for the treatment of painful conditions.

7-chloro-4-(phenylselanyl) quinoline prevents dopamine depletion in a Drosophila melanogaster model of Parkinson's-like disease.

Neurodegeneration in Parkinson's disease appears to be caused by multiple factors, including oxidative damage and an increase in acetylcholinesterase expression that can culminate in loss of dopaminergic neurons. A selenium-containing quinoline derivative, 7-chloro-4-(phenylselanyl) quinoline (4-PSQ), shows important pharmacological actions mainly attributed to its antioxidant and anticholinesterase properties. Thus, this study investigated the neuroprotective effect of 4-PSQ in a model of Parkinson's-like disease induced by rotenone (ROT) in Drosophila melanogaster and verified whether these effects are related to selenium levels. Adult flies were divided into: [1] control, [2] 4-PSQ (25 µM), [3] ROT (500 µM), and [4] 4-PSQ (25 µM) + ROT (500 µM) groups and exposed to a diet containing ROT and/or 4-PSQ for 7 days, according to their respective groups. Survival, behavioral, and ex vivo analyses were performed. Dopamine levels, reactive species levels (RS), lipid peroxidation (LPO), superoxide dismutase (SOD) and catalase (CAT) activity, and proteic thiol (PSH) and non-proteic thiol (NPSH) content in the head region were analyzed, while acetylcholinesterase (AChE) activity and selenium levels in the head and body regions were analyzed. 4-PSQ was able to reverse the ROT-induced deficits in flies, reestablish dopamine and selenium levels, reverse cholinergic deficits, improve motor function, and ameliorate mortality. Furthermore, 4-PSQ also reduced RS levels and LPO, and restored the activities of the antioxidant enzymes, SOD and CAT. Interestingly, a positive relationship between dopamine and selenium levels could be seen. Our results demonstrate the neuroprotective effect of 4-PSQ, and we suggest that the compound may act via different mechanisms, such as improving antioxidant defenses and consequently reducing oxidative damages, as well as having an anticholinesterase action, which together can prevent dopamine depletion, as these actions were correlated with the presence of selenium in the 4-PSQ molecule.

7-Chloro-4-phenylsulfonyl quinoline, a new antinociceptive and anti-inflammatory molecule: Structural improvement of a quinoline derivate with pharmacological activity.

The present study was designed to examine the antinociceptive and anti-inflammatory effects of 7-chloro-4-phenylsulfonyl quinoline (PSOQ). Mice were orally (p.o) pretreated with PSOQ (0.01-10 mg/kg), meloxicam (10 mg/kg), 30 min prior to the acetic acid, hot-plate and open field tests. PSOQ reduced abdominal writhing induced by acetic acid, while meloxicam presented no effect. The latency time in the hot-plate test and locomotor/exploratory activities in the open field test were not altered by treatments. In order to evaluate the gastric tolerability after oral administration of PSOQ or meloxicam (10 mg/kg), mice were fasted for 18 h prior to drug exposure. Four hours later, the development of lesions was assessed. PSOQ and meloxicam did not induce ulcer at the dose and time evaluated. Indeed, anti-inflammatory and anti-edematogenic properties of PSOQ were investigated. For this, animals were pretreated with PSOQ (0.01-50 mg/kg; p.o.), meloxicam (50 mg/kg; p.o.), 30 min prior to croton oil application. PSOQ and meloxicam (50 mg/kg) diminished the edema formation and myeloperoxidase activity induced by croton oil in the ear tissue. Taken together these data demonstrated that PSOQ exerts acute anti-inflammatory and antinociceptive actions, suggesting that it may represent an alternative in the development of future new therapeutic strategies.