Neuroprotective Potential of a Novel Soluble Guanylate Cyclase Stimulator the Riociguat Alone or in a Combination Manner with Resveratrol in Experimental Stroke Model in Rats / Potencial Neuroprotector del Novedoso Estimulador de Guanilato Ciclasa Soluble, el Riociguat solo o en Combinación con Resveratrol en un Modelo Experimental de Ataque Cerebrovascular en Ratas

SUMMARY: In this study we aimed to examine the effect of novel vasodilatory drug Riociguat co-administration along resveratrol to recover neurodegeneration in experimental stroke injury. For that purpose, thirty-five adult female rats were divided into five groups (Control, MCAO, MCAO + R, MCAO + BAY, MCAO + C) of seven animals in each. Animals in Control group did not expose to any application during the experiment and sacrificed at the end of the study. Rats in the rest groups exposed to middle cerebral artery occlusion (MCAO) induced ischemic stroke. MCAO + R group received 30 mg/kg resveratrol, and MCAO + BAY group received 10 mg/kg Riociguat. The MCAO + C group received both drugs simultaneously. The drugs were administered just before the reperfusion, and the additional doses were administered 24h, and 48h hours of reperfusion. All animals in this study were sacrificed at the 72nd hour of experiment. Total brains were received for analysis. Results of this experiment indicated that MCAO led to severe injury in cerebral structure. Bax, IL-6 and IL-1ß tissue levels were up-regulated, but anti-apoptotic Bcl-2 immunoexpression was suppressed (p<0.05). In resveratrol and Riociguat treated animals, the neurodegenerations and apoptosis and inflammation associated protein expressions were improved compared to MCAO group, but the most success was obtained in combined treatment exposed animals in MCAO + C group. This study indicated that the novel soluble guanylate stimulator Riociguat is not only a potent neuroprotective drug in MCAO induced stroke, but also synergistic administration of Riociguat along with resveratrol have potential to increase the neuroprotective effect of resveratrol in experimental cerebral stroke exposed rats.

En este estudio, nuestro objetivo fue examinar el efecto de la coadministración del nuevo fármaco vasodilatador Riociguat junto con resveratrol para recuperar la neurodegeneración en lesiones por ataques cerebrovasculares experimentales. Para ello, se dividieron 35 ratas hembras adultas en cinco grupos (Control, MCAO, MCAO + R, MCAO + BAY, MCAO + C) de siete animales en cada uno. Los animales del grupo control no fueron sometidos a ninguna aplicación durante el experimento y se sacrificaron al final del estudio. Las ratas de los grupos expuestas a la oclusión de la arteria cerebral media (MCAO) indujeron un ataque cerebrovascular isquémico. El grupo MCAO + R recibió 30 mg/kg de resveratrol y el grupo MCAO + BAY recibió 10 mg/kg de Riociguat. El grupo MCAO + C recibió ambos fármacos simultáneamente. Los fármacos se administraron antes de la reperfusión y las dosis adicionales se administraron a las 24 y 48 horas de la reperfusión. Todos los animales en este estudio fueron sacrificados a las 72 horas del experimento. Se recibieron cerebros totales para su análisis. Los resultados indicaron que la MCAO provocaba lesiones graves en la estructura cerebral. Los niveles tisulares de Bax, IL-6 e IL- 1ß estaban regulados positivamente, pero se suprimió la inmunoexpresión antiapoptótica de Bcl-2 (p <0,05). En los animales tratados con resveratrol y Riociguat, las neurodegeneraciones y las expresiones de proteínas asociadas a la apoptosis y la inflamación mejoraron en comparación con el grupo MCAO, sin embargo el mayor éxito se obtuvo en el tratamiento combinado de animales expuestos en el grupo MCAO + C. Este estudio indicó que el nuevo estimulador de guanilato ciclasa soluble Riociguat no solo es un fármaco neuroprotector potente en el ataque cerebrovascular inducido por MCAO, sino que también la administración sinérgica de Riociguat junto con resveratrol tiene el potencial para aumentar el efecto neuroprotector del resveratrol en ratas experimentales expuestas a un ataque cerebrovascular.

Neuroprotective effects of the combined treatment of resveratrol and urapidil in experimental cerebral ischemia-reperfusion injury in rats

ABSTRACT Purpose: To evaluate the neuroprotective effect of resveratrol, urapidil, and a combined administration of these drugs against middle cerebral artery occlusion (MCAO) induced ischemia/reperfusion (IR) injury model in rats. Methods: Thirty-five rats were divided into five groups of seven animals each. Animals in IR, IR resveratrol (IRr), IR urapidil (IRu), and IR + combination of resveratrol and urapidil (IRc) were exposed to MCAO induced cerebral ischemia reperfusion injury model. Rats in IRr and IRu groups received 30-mg/kg resveratrol and 5-mg/kg urapidil respectively. Animals in IRc received a combined treatment of both drugs. At the end of the study, brain tissues were used for oxidative stress (malondialdehyde, glutathione, and superoxide dismutase), pro-apoptotic caspase-3, anti-apoptotic Bcl-2, and pro-inflammatory tumor necrosis factor-α cytokine level measurements. Results: The MCAO model successfully replicated IR injury with significant histopathological changes, elevated tissue oxidative stress, and upregulated apoptotic and inflammatory protein expression in IR group compared to control group (p < 0.001). All parameters were significantly alleviated in IRr group compared to IR group (all p < 0.05). In IRu group, all parameters except for caspase-3 and Bcl-2 were also significantly different than IR group (all p < 0.05). The IRc group showed the biggest difference compared to IR group in all parameters (all p < 0.001). The IRc had higher superoxide dismutase and Bcl-2 levels, and lower caspase-3 levels compared to both IRr and IRu groups (all p < 0.05). Also, the IRc group had lower MDA and TNF-α levels compared to IRu group (all p < 0.05). Conclusions: The results indicate that combined treatment of resveratrol and urapidil may be a novel strategy to downregulate neurodegeneration in cerebral IR injury.