RESUMO
Rosmarinic acid (RA) is an important component of Chinese herbal medicine treatments and has been demonstrated to exert therapeutic effects in mood disorders. The present study was designed to assess the effects of RA on post-traumatic stress disorder (PTSD)-like symptoms, hippocampal cell proliferation and phosphorylation extracellular regulated protein kinases (pERK1/2) expression. We found that administration of RA (10mg/kg) alleviated PTSD-like symptoms in rats exposed to an enhanced single prolonged stress (ESPS) paradigm and restored hippocampal proliferation and pERK1/2 expression. Interestingly, the effects of RA were inhibited by the blockage of the ERK signaling. These data support the use of RA for treating PTSD and indicate that the ERK1/2 signaling cascade may play a critical role in the therapeutic efficacy of RA in treating such conditions.
Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Cinamatos/uso terapêutico , Depsídeos/uso terapêutico , Hipocampo/efeitos dos fármacos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/patologia , Análise de Variância , Animais , Bromodesoxiuridina/metabolismo , Butadienos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Reação de Congelamento Cataléptica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Nitrilas/farmacologia , Ratos , Ratos Sprague-Dawley , Ácido RosmarínicoRESUMO
The present study examined the hypothesis that spinal cord ischemic tolerance induced by hyperbaric oxygen (HBO) preconditioning is triggered by an initial oxidative stress and is associated with an increase of antioxidant enzyme activities as one effector of the neuroprotection. New Zealand White rabbits were subjected to HBO preconditioning, hyperbaric air (HBA) preconditioning, or sham pretreatment once daily for five consecutive days before spinal cord ischemia. Activities of catalase (CAT) and superoxide dismutase were increased in spinal cord tissue in the HBO group 24 h after the last pretreatment and reached a higher level after spinal cord ischemia for 20 mins followed by reperfusion for 24 or 48 h, in comparison with those in control and HBA groups. The spinal cord ischemic tolerance induced by HBO preconditioning was attenuated when a CAT inhibitor, 3-amino-1,2,4-triazole,1 g/kg, was administered intraperitoneally 1 h before ischemia. In addition, administration of a free radical scavenger, dimethylthiourea, 500 mg/kg, intravenous, 1 h before each day's preconditioning, reversed the increase of the activities of both enzymes in spinal cord tissue. The results indicate that an initial oxidative stress, as a trigger to upregulate the antioxidant enzyme activities, plays an important role in the formation of the tolerance against spinal cord ischemia by HBO preconditioning.