Ameliorative potential of Vernonia cinerea on chronic constriction injury of sciatic nerve induced neuropathic pain in rats

The aim of the present study is to investigate the ameliorative potential of ethanolic extract of whole plant of Vernonia cinerea in the chronic constriction injury (CCI) of sciatic nerve induced neuropathic pain in rats. Behavioral parameters such as a hot plate, acetone drop, paw pressure, Von Frey hair and tail immersion tests were performed to assess the degree of thermal, chemical and mechanical hyperalgesia and allodynia. Biochemical changes in sciatic nerve tissue were ruled out by estimating thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and total calcium levels. Ethanolic extract of Vernonia cinerea and pregabalin were administered for 14 consecutive days starting from the day of surgery. CCI of sciatic nerve has been shown to induce significant changes in behavioral, biochemical and histopathological assessments when compared to the sham control group. Vernonia cinerea attenuated in a dose dependent manner the above pathological changes induced by CCI of the sciatic nerve, which is similar to attenuation of the pregabalin pretreated group. The ameliorating effect of ethanolic extract of Vernonia cinerea against CCI of sciatic nerve induced neuropathic pain may be due to the presence of flavonoids and this effect is attributed to anti-oxidative, neuroprotective and calcium channel modulator actions of these compounds

Ameliorative potential of Butea monosperma on chronic constriction injury of sciatic nerve induced neuropathic pain in rats

The present study was designed to investigate the ameliorative role of ethanolic extract from leaves of Butea monosperma in chronic constriction injury (CCI) of sciatic nerve induced neuropathic pain in rats. Hot plate, acetone drop, paw pressure, Von Frey hair and tail immersion tests were performed to assess the degree of thermal hyperalgesia, cold chemical allodynia, mechanical hyperalgesia & allodynia in the left hind paw and tail thermal hyperalgesia. Further on, thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) and total calcium levels were estimated to assess the biochemical changes in the sciatic nerve tissue. Histopathological changes were also observed in the sciatic nerve tissue. Ethanolic extract of Butea monosperma leaves and pregabalin (serving as positive control) were administered for 14 consecutive days starting from the day of surgery. CCI resulted in significant changes in behavioural and biochemical parameters. Pretreatment of Butea monosperma attenuated CCI induced development of behavioural, biochemical and histopathological alterations in a dose dependent manner, which is comparable to that of pregabalin pretreated group. These findings may be attributed to its potential anti-oxidative, neuroprotective and calcium channel modulatory actions of Butea monosperma.<br>O presente trabalho visou investigar o papel do extrato etanólico de folhas de Butea monosperma no alívio da dor neuropática pela injúria de constrição crônica (CCI) do nervo ciático induzida em ratos. Placa quente, gota de acetona, pressão na pata, testes de imersão de pelo e cauda de Von Frey foram utilizados para acessar o grau de hiperalgesia térmica, alodinia química fria, hiperalgesia mecânica e alodinia na pata trazeira esquerda e hiperalgesia térmica da cauda. Além disso, substâncias reativas com ácido tiobarbitúrico (TBARS), glutatião reduzido (GSH) e níveis de cálcio total foram estimados para acessar as alterações bioquímicas no tecido do nervo ciático. Alterações histopatológicas foram também observadas no tecido do nervo ciático. O extrato etanólico das folhas de Butea monosperma e pregabalina (servindo de controle positivo) foram administrados por 14 dias consecutivos, iniciando-se no dia da cirurgia. CCI resultou em alterações significativas nos parâmetros comportamentais e bioquímicos. Pretratamento com Butea monosperma atenuou o desenvolvimento das alterações comportamentais, bioquímicas e histopatológicas induzidas pela CCI de maneira dose dependente, comparável ao grupo pretratado com pregabalina. Esses resultados podem ser atribuídos ao potencial antioxidativo, neuroprotetor e às ações modulatórias de canais de cálcio da Butea monosperma