Neuroprotective effects of rutin against cuprizone-induced multiple sclerosis in mice

Multiple sclerosis (MS) is a chronic inflammatory neurodegenerative disease of the central nervous system that injures the myelin sheath, provoking progressive axonal degeneration and functional impairments. No efficient therapy is available at present to combat such insults, and hence, novel safe and effective alternatives for MS therapy are extremely required. Rutin (RUT) is a flavonoid that exhibits antioxidant, anti-inflammatory, and neuroprotective effects in several brain injuries. The present study evaluated the potential beneficial effects of two doses of RUT in a model of pattern-III lesion of MS, in comparison to the conventional standard drug; dimethyl fumarate (DMF). Demyelination was induced in in male adult C57BL/6 mice by dietary 0.2% (w/w) cuprizone (CPZ) feeding for 6 consecutive weeks. Treated groups received either oral RUT (50 or 100 mg/kg) or DMF (15 mg/kg), along with CPZ feeding, for 6 consecutive weeks. Mice were then tested for behavioral changes, followed by biochemical analyses and histological examinations of the corpus callosum (CC). Results revealed that CPZ caused motor dysfunction, demyelination, and glial activation in demyelinated lesions, as well as significant oxidative stress, and proinflammatory cytokine elevation. Six weeks of RUT treatment significantly improved locomotor activity and motor coordination. Moreover, RUT considerably improved remyelination in the CC of CPZ + RUT-treated mice, as revealed by luxol fast blue staining and transmission electron microscopy. Rutin also significantly attenuated CPZ-induced oxidative stress and inflammation in the CC of tested animals. The effect of RUT100 was obviously more marked than either that of DMF, regarding most of the tested parameters, or even its smaller tested dose. In silico docking revealed that RUT binds tightly within NF-κB at the binding site of the protein-DNA complex, with a good negative score of -6.79 kcal/mol. Also, RUT-Kelch-like ECH-associated protein 1 (Keap1) model clarifies the possible inhibition of Keap1-Nrf2 protein-protein interaction. Findings of the current study provide evidence for the protective effect of RUT in CPZ-induced demyelination and behavioral dysfunction in mice, possibly by modulating NF-κB and Nrf2 signaling pathways. The present study may be one of the first to indicate a pro-remyelinating effect for RUT, which might represent a potential additive benefit in treating MS.

Cardiosphere-Derived Cells Facilitate Heart Repair by Modulating M1/M2 Macrophage Polarization and Neutrophil Recruitment

Cardiosphere-derived cells (CDCs), one of the promising stem cell sources for myocardial repair, have been tested in clinical trials and resulted in beneficial effects; however, the relevant mechanisms are not fully understood. In this study, we examined the hypothesis that CDCs favor heart repair by switching the macrophages from a pro-inflammatory phenotype (M1) into a regulatory anti-inflammatory phenotype (M2). Macrophages from mice were cultured with CDCs-conditioned medium or with fibroblasts-conditioned medium as a control. Immunostaining showed that CDCs-conditioned medium significantly enhanced the expression of CD206 (a marker for M2 macrophages), but decreased the expression of CD86 (a marker for M1 macrophages) 3 days after culture. For animal studies, we used an acute myocardial infarction model of mice. We injected CDCs, fibroblasts, or saline only into the border zone of infarction. Then we collected the heart tissues for histological analysis 5 and 14 days after treatment. Compared with control animals, CDCs treatment significantly decreased M1 macrophages and neutrophils but increased M2 macrophages in the infarcted heart. Furthermore, CDCs-treated mice had reduced infarct size and fewer apoptotic cells compared to the controls. Our data suggest that CDCs facilitate heart repair by modulating M1/M2 macrophage polarization and neutrophil recruitment, which may provide a new insight into the mechanisms of stem cell-based myocardial repair.

Antiapoptotic and antioxidant effects of carvedilol and vitamin E protect against diabetic nephropathy and cardiomyopathy in diabetic Wistar albino rats

Carvedilol is a novel β-adrenoreceptor blocker, with antioxidant properties inhibiting lipid peroxidation and preventing the depletion of endogenous antioxidants. Moreover, carvedilol was reported to enhance the expression of Bcl-2 gene, which has antioxidant and antiapoptotic effects. There are few researches testing the protective effect of carvedilol on the development of diabetic cardiomyopathy and nephropathy. In this study, we induced diabetes mellitus in male Wistar albino rats. We investigated carvedilol, as well as vitamin E, administrated in healthy and diabetic rats for 6 weeks to compare their effects on biochemical parameters and the expression of Bcl-2 protein in both myocardial and renal tissues by immunohistochemistry. The study showed that the diabetic rats not only had renal dysfunction and more myocardial damage, but also showed lower expression of Bcl-2 protein. Carvedilol and vitamin E treatments were associated with better renal function and less myocardial damage, lower blood glucose, and lipid peroxidation, higher antioxidant capacity, better serum lipids, and higher expression of Bcl-2 protein in diabetic rats. These results indicate that carvedilol and vitamin E treatments partly protect against myocardial and renal damage probably via their antioxidant and antiapoptotic properties in diabetic rats.

Enhancement of 5-fluoro-2'-deoxyuridine antitumor efficacy by the uridine phosphorylase inhibitor 5-(benzyloxybenzyl)barbituric acid acyclonucleoside

5-(Benzyloxybenzyl)barbituric acid acyclonucleoside (BBBA) was recently synthesized as a potent and specific inhibitor of uridine phosphorylase (EC 2.4.2.3), the enzyme responsible for the catabolism of 5-fluoro-2'-deoxyuridine (FdUrd) in many types of tumors that are deficient or have little thymidine phosphorylase (EC 2.4.2.4) activity. The effect of BBBA on modulating the antitumor efficacy of FdUrd was evaluated in vitro, against the human colon carcinomas DLD-1 and HCT-15 grown in culture, and in vivo, against DLD-1 grown as xenografts in anti-thymocyte serum immunosuppressed mice. The concentrations of FdUrd that produced 50% growth inhibition after a 3-h exposure were 88 and 340 nM for HCT-15 and DLD-1, respectively. BBBA alone, at all concentrations tested, had no significant effect on the growth of DLD-1 and HCT-15 in culture. However, BBBA at 5, 10, 20, and 40 nM potentiated (P < 0.05) the cytotoxicity of FdUrd (340 nM; 3 h) against DLD-1 in culture by 20, 33, 55, and 63%, respectively. Similarly, BBBA at 10 and 20 nM potentiated the cytotoxicity of FdUrd (88 nM; 3 h) against HCT-15 in culture by 37 and 45%, respectively. In soft agar, BBBA (10 nM) also enhanced the cytocidal effect of FdUrd (10 and 32 nM) against DLD-1 by 41 and 55%, respectively, and against HCT-15 by 6 and 31%, respectively. Increasing BBBA dose to 20 nM enhanced further the FdUrd (10 and 32 nM) cytotoxicity against DLD-1 by 76 and 77%, respectively, and HCT-15 by 31 and 48%, respectively. BBBA also potentiated the chemotherapeutic efficacy of FdUrd in anti-thymocyte serum immunosuppressed mice bearing DLD-1 xenografts with no apparent host toxicity. At a low tumor burden (2.5 x 10(6) cells/mouse), 2 days treatment with FdUrd alone (50 mg/kg/day x 2) did not result in significant reduction in tumor volume. Coadministration of BBBA at 5 and 10 mg/kg/day x 2 did not potentiate the efficacy of FdUrd over that achieved by FdUrd alone, but it significantly reduced the tumor volume by 27 and 32%, respectively, when compared with untreated controls. FdUrd alone at 150 mg/kg/day x 2 reduced the tumor volume by 29%. This reduction in tumor volume was enhanced 1.8-fold by coadministration of BBBA (10 mg/kg/day x 2). At a higher tumor burden (5 x 10(6) cells/mouse) and 4 days treatment, BBBA at 10 and 30 mg/kg/day x 4 reduced further the tumor volume produced by FdUrd alone (200 mg/kg/day x 4) by 1.2- and 1.4-fold, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)