Bamboo Leaf Flavone Regulates microRNA-127-5p to Hinder Interleukin-1 Beta-induced Chondrocyte Damage

Abstract

Prior studies have reported that bamboo leaf flavone possess biological and pharmacological activities in mammals. Yet, the effect and possible mechanism of bamboo leaf flavone on interleukin-1 beta-induced chondrocyte damage is still unclear. Methods interleukin-1 beta was used to induce human chondrocytes to establish a cell injury model, followed by exposure to different doses of bamboo leaf flavone. Apoptosis rate was analyzed using flow cytometry. Superoxide dismutase and lactate dehydrogenase activities were assessed using a kit. Interleukin-6 and interleukin-10 levels were determined using enzyme-linked immunosorbent assay. Quantitative reverse transcription-polymerase chain reaction analyzed microRNA-127-5p content. MicroRNA-NC and microRNA-127-5p mimics were transfected into chondrocytes, followed by treatment with interleukin-1 beta for 24 h. Cleaved caspase-3 and cleaved caspase-9 protein expression were monitored using Western blot. After bamboo leaf flavone treatment, apoptosis rate, cleaved caspase-3 and cleaved caspase-9 protein levels, lactate dehydrogenase activity, and interleukin-6 level were decreased, while microRNA-127-5p expression, superoxide dismutase activity, and interleukin-10 level were increased in dose-dependent ways. Upregulated microRNA-127-5p hindered apoptosis rate, cleaved caspase-3 and cleaved caspase-9 protein levels, the activity of lactate dehydrogenase, and the level of interleukin-6, and increased superoxide dismutase activity and interleukin-10 level. MicroRNA-127-5p knockdown could antagonize the effects of bamboo leaf flavone on interleukin-1 beta-mediated chondrocyte apoptosis, oxidative stress and inflammation. Bamboo leaf flavone exposure could inhibit cell apoptosis, oxidative stress and inflammation by up-regulating microRNA-127-5p expression, thereby reducing interleukin-1 beta-induced chondrocyte damage.