RESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Ginseng, the root of Panax ginseng C.A. Meyer, is a traditional medicinal herb that has been widely used in Asia for the treatment of many diseases through its effects of reinforcing vitality, strengthening the bodily resistance to pathogenic factors, engendering body liquids and allaying thirst, relieving uneasiness of the body and mind and benefiting intelligence, reducing body weight and prolonging life. Ginsenosides are the most important biologically active substances in ginseng. Many reports have suggested that ginsenosides could exert prominent neuroprotective and neurotrophic effects, promote neural stem/progenitor cell (NSC) proliferation and promote neurite outgrowth and neuronal network formation. The present study aimed to investigate whether treatment with ginsenosides could facilitate NSC proliferation in the hippocampal formation after traumatic brain injury (TBI) and contribute to the recovery of neurological functions including learning and memory. MATERIALS AND METHODS: The modified Feeney׳s method was used to induce a TBI in rats. Ginseng total saponins (GTS) were treated intraperitoneally twice a day for 1 week after the TBI. The neurological functions, morphology of the hippocampus, expression of nerve growth-related factors and number of NSCs in the hippocampal formation ipsilateral to the trauma were determined. RESULTS: We determined 1) GTS (5-80 mg/kg) treatment after a TBI improved the recovery of neurological functions, including learning and memory, and reduced cell loss in the hippocampal area. The effects of GTS at 20, 40, 60, and 80 mg/kg were better than the effects of GTS at 5 and 10 mg/kg. 2) GTS treatment (20 mg/kg) after a TBI increased the expression of NGF, GDNF and NCAM, inhibited the expression of Nogo-A, Nogo-B, TN-C, and increased the number of BrdU/nestin positive NSCs in the hippocampal formation. CONCLUSIONS: GTS treatment in rats after a TBI alleviated the secondary brain injury and ameliorated the neurological functions with an effective dose limit of 5-80 mg/kg. GTS regulated the expression of nerve growth-related factors and improved the proliferation of neural stem/progenitor cells, which might facilitate neural regeneration and tissue repair, and might contribute to the recovery of neurological functions, including learning and memory. These effects of GTS might provide a foundation for the use of ginseng as a medicinal herb to enhance intelligence, reduce the aging process and prolong life in the traditional medicine.
Assuntos
Lesões Encefálicas/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Panax , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/psicologia , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Memória/efeitos dos fármacos , Fator de Crescimento Neural/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Fármacos Neuroprotetores/isolamento & purificação , Panax/química , Fitoterapia , Extratos Vegetais/isolamento & purificação , Raízes de Plantas , Plantas Medicinais , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Saponinas/isolamento & purificação , Fatores de TempoRESUMO
OBJECTIVE: To investigate the neuroprotective effect, effective dose and time window of ginseng total saponins (GTS) treatment in rat after traumatic brain injury (TBI). METHODS: The modified Feeney's method was used to establish TBI model in rat. GTS was treated intraperitoneally. The neurological function and histological morphology of brain tissue were observed. RESULTS: Different doses of GTS were used 6 h after TBI. The neurological and histological results showed that: compared with the TBI group, significant efficacy was observed 2 - 14 days after injury with GTS treatment at 10, 20, 40, 60 and 80 mg/kg (P < 0.05); The effects of GTS at 20, 40, and 60 mg/kg were better than those of GTS at 10 and 80 mg/kg. During the research on the time window of GTS intervention, GTS (20 mg/kg) showed significant effect when used at 3 h and 6 h after TBI; however 12 h, 24 h after TBI, application of GTS did not exert any significant effect. CONCLUSION: GTS intervention after TBI could reduce brain damage and promote recovery of the neurological function. Among doses of GTS 5 - 80 mg/kg, 20 - 60 mg/kg is the best dose limit. The effective time window of GTS is 6 h after TBI.