ABSTRACT
Many studies have shown a close association between Nogo-B and inflammation-related diseases. However, uncertainty does exist, regarding Nogo-B function in the pathological progression of cerebral ischemia/reperfusion (I/R) injury. Middle cerebral artery occlusion/reperfusion (MCAO/R) model was utilized in C57BL/6L mice to mimic ischemic stroke in vivo. Using oxygen-glucose deprivation and reoxygenation (ODG/R) model in microglia cells (BV-2) to establish cerebral I/R injury in vitro. Various methods, including Nogo-B siRNA transfection, mNSS and the rotarod test, TTC, HE and Nissl staining, immunofluorescence staining, immunohistochemistry, Western blot, ELISA, TUNEL and qRT-PCR were employed to probe into the effect of Nogo-B downregulation on cerebral I/R injury and the potential mechanisms. A small amount of Nogo-B expression (protein and mRNA) was observed in cortex and hippocampus before ischemia, then Nogo-B expression increased significantly on day 1, reaching the maximum on day 3, remaining stable on day 14 after I/R, and decreasing gradually after 21 days, but it still rose significantly compared with that observed preischemia. Nogo-B down-regulation could markedly reduce the neurological score and infarct volume, improve the histopathological changes and neuronal apoptosis, lower the number of CD86+/Iba1+ cells and the levels of IL-1ß, IL-6, and TNF-α, and raise the density of NeuN fluorescence, the number of CD206+/Iba1+ cells, and the level of IL-4, IL-10 and TGF-ß in brain of MCAO/R mice. Treatment with Nogo-B siRNA or TAK-242 in BV-2 cells could obviously decrease the CD86 fluorescence density and the mRNA expression of IL-1ß, IL-6 and TNF-α, increase CD206 fluorescence density and the mRNA expression of IL-10 after OGD/R injury. In addition, the expression of TLR4, p-IκBα and p-p65 proteins significantly increased in the brain after MCAO/R and BV-2 cells exposed to OGD/R. Treatment with Nogo-B siRNA or TAK-242 prominently reduced the expression of TLR4, p-IκBα and p-p65. Our findings suggest that the down-regulation of Nogo-B exerts protective effect on cerebral I/R injury by modulating the microglia polarization through inhibiting TLR4/NF-κB signaling pathway. Nogo-B may be a potential therapeutic target for ischemic stroke.
Subject(s)
Brain Ischemia , Ischemic Stroke , Reperfusion Injury , Animals , Mice , Brain Ischemia/metabolism , Down-Regulation , Infarction, Middle Cerebral Artery/metabolism , Interleukin-10/genetics , Interleukin-10/metabolism , Interleukin-10/pharmacology , Interleukin-6/metabolism , Ischemic Stroke/metabolism , Mice, Inbred C57BL , Microglia/metabolism , NF-kappa B/metabolism , NF-KappaB Inhibitor alpha/genetics , NF-KappaB Inhibitor alpha/metabolism , NF-KappaB Inhibitor alpha/pharmacology , Reperfusion Injury/metabolism , RNA, Messenger/metabolism , RNA, Small Interfering/pharmacology , Toll-Like Receptor 4/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
<p><b>Objective</b>To investigate the effect of Kangshuailing Gao (KG) on benign prostatic hyperplasia (BPH) in rats and its action mechanisms.</p><p><b>METHODS</b>Fifty BPH model rats were randomized into five groups of equal number, BPH model control, finasteride control, and high-, medium- and low-dose KG, to be treated intragastrically with distilled water, finasteride solution at 0.52 mg/kg, and KG solution at 4.16, 2.08 and 1.04 g/kg respectively once a day for 30 days consecutively. Another 10 normal healthy rats were taken as blank controls. The rats were weighed once a week during the treatment. The wet weight and index of the prostate were obtained after treatment, followed by measurement of the contents of serum estradiol (E2) and dihydrotestosterone (DHT), testosterone (T) and hypoxia-inducible factor-1α (HIF-1α) in the prostatic tissue, and observation of histomorphological changes in the prostate under the light microscope.</p><p><b>RESULTS</b>Compared with the BPH model control group, high- and medium-dose KG significantly reduced the prostate wet weight (［0.84 ± 0.08］ vs ［0.69 ± 0.04］ and ［0.71 ± 0.07］ g, P < 0.01), the prostatic index (［0.28 ± 0.03］% vs ［0.20 ± 0.02］% and ［0.22 ± 0.03］%, P < 0.01), and the levels of T (［4.63 ± 1.25］ vs ［2.44 ± 0.47］ and ［2.91 ± 0.69］ ng/L, P < 0.01) and DHT (［154.44 ± 20.25］ vs ［88.23 ± 13.63］ and ［90.52 ± 16.44］ nmol/L, P < 0.01), but increased the level of E2 (［0.95 ± 0.24］ vs ［1.19 ± 0.14］ and ［1.20 ± 0.22］ nmol/L, P < 0.01) in the serum. High-dose KG remarkably reduced the overexpression of HIF-1α in the prostate tissue of the BPH model rats (P < 0.01) and alleviated such BPH-related symptoms as epithelium thinning, intraglandular secretion reduction, and interstitial substance decrease.</p><p><b>CONCLUSIONS</b>Kangshuailing Gao acted effectively on BPH in the model rats by reducing the androgen level, balancing the estrogen/androgen ratio, and downregulating the expression of HIF-1α in the prostate tissue.</p>