Effect and mechanism of oxycodone hydrochloride on inflammation and neuronal apoptosis in epileptic rats / 中华老年心脑血管病杂志

ABSTRACT

Objective To explore the effect of oxycodone hydrochloride on inflammation and neuro-nal apoptosis in epileptic rats through c-Jun amino terminal kinase(JNK)/p38 mitogen activated protein kinase(p38 MAPK)signaling pathway.Methods After epileptic rat model was success-fully constructed,72 epileptic rats were randomly divided into model group,low-,medium-and high-dose oxycodone hydrochloride groups(0.125,0.25 and 0.5 mg/kg),anisomycin(JNK activa-tor 5 mg/kg)and combined group(0.5 mg/kg oxycodone hydrochloride+5 mg/kg anisomycin),with 12 rats in each group.Another 12 healthy rats were selected as control group.In 24 h after the end of administration,the frequency and duration of seizures were recorded for all rats.ELISA was used to detect the serum levels of TNF-α and IL-6,HE staining was employed to observe the his-topathological changes in hippocampal CA1 region,and TUNEL staining was applied to detect the apoptosis of CA1 region neurons.The expression of JNK,p-JNK,p38 MAPK,p-p38 MAPK and Caspase-3 in hippocampal CA1 region was detected by Western blotting.Results Compared with the rats from the control group,those of the model group showed higher frequency and longer du-ration of seizures,higher serum TNF-α and IL-6 levels,increased apoptotic rate of hippocampal CA1 neurons,and elevated p-JNK/JNK ratio,p-p38 MAPK/p38 MAPK ratio and Caspase-3 expression(P＜0.05).While low-,medium-and high-dose oxycodone hydrochloride treatment re-versed above changes in frequency and duration of seizures,serum TNF-α and IL-6 levels,neuro-nal apoptosis,p-JNK/JNK ratio,p-p38 MAPK/p38 MAPK ratio and Caspase-3 expression(P＜0.05).In the anisomycin group,higher frequency and longer duration of seizures,elevated serum TNF-α and IL-6 levels,increased neuronal apoptotic rate in hippocampal CA1 region,and en-hanced p-JNK/JNK ratio,p-p38 MAPK/p38 MAPK ratio and Caspase-3 expression(P＜0.05).Lower frequency and shorter duration of seizures,decreased serum TNF-α and IL-6 levels,and re-duced neuronal apoptotic rate in hippocampal CA1 region were observed in the combined group than the anisomycin group(P＜0.05).The combined group obtained statistically lower p-JNK/JNK ratio,p-p38 MAPK/p38 MAPK ratio and Caspase-3 expression in hippocampal CA1 region than the high-dose group,and opposite results than the anisomycin group(0.89±0.12 vs 0.25± 0.05 vs 1.08±0.16,0.81±0.08 vs 0.21±0.04 vs 0.94±0.12,0.79±0.12 vs 0.26±0.04 vs 0.89± 0.14,P＜0.05).Conclusion Oxycodone hydrochloride can reduce inflammatory response,im-prove epileptic symptoms and pathological damages,and protect neurons in epileptic rats,which is related to the inhibition of JNK/p38 MAPK signaling pathway.