黄葵胶囊对阿霉素肾病肾组织炎症信号通路p38MAPK的干预作用

目的:阐明黄蜀葵花(Abelmoschus manihot,AM)提取物制剂——黄葵胶囊(Huangkui capsule,HKC)调节阿霉素肾病(adriamycin-induced nephropathy,ADRN)模型p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)信号通路从而改善肾组织炎症性损伤的机制.方法:将19只SD大鼠随机分为假手术组、对照组和HKC组.对HKC组和对照组大鼠行右侧肾摘除术,并在4周内分2次经颈静脉注射阿霉素(adriamycin,ADR)建立ADRN模型.HKC组大鼠于第2次注射ADR后经灌胃给予HKC悬浊液,对照组和假手术组大鼠同时经灌胃给予蒸馏水,共干预4周.在HKC和蒸馏水干预前和干预后第1,2,3,4周末,分别称量大鼠体重,并检测24 h尿蛋白排泄量(24 h urinary protein excretion,Upro).肾摘除术后第8周末处死全部大鼠,抽取血液,摘除左肾并称重,观察血清生化指标、肾小球形态特征、肾小球α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、Ⅰ型胶原(collagen type Ⅰ)表达特征、肾小球巨噬细胞(macrophage,Mφ)浸润特征等,并且检测肾组织转化生长因子(transforming growth factor,TGF)-β1,p38MAPK,磷酸化p38MAPK(phosphorylated p38MAPK,p-p38MAPK)蛋白相对表达量.结果:与对照组大鼠比较,HKC改善了模型鼠的蛋白尿和血清白蛋白(albumin,Alb),抑制了模型鼠系膜细胞(mesangial cell,MC)增殖、细胞外基质(extracellular matrix,ECM)及其胶原成分沉积,减轻了肾小球α-SMA,Ⅰ型胶原表达,减轻了肾小球ED1+,ED3+浸润,下调了模型鼠肾组织TGF-β1,p-p38MAPK蛋白表达.结论:HKC在体内具有减轻肾组织炎症性损伤的作用;HKC通过下调肾组织p38MAPK信号通路中关键信号分子——p-p38MAPK的蛋白表达,干预其相关信号通路的信号转导途径,减少肾组织内TGF-β1的表达和炎症细胞的浸润、活化,从而改善肾组织的炎症性损伤.     

黄葵胶囊抑制糖尿病肾病肾组织氧化应激和p38MAPK信号通路活性改善肾纤维化的作用和机制

目的:探讨黄葵胶囊(Huangkui capsule,HKC)改善糖尿病肾病(diabetic nephropathy,DN)模型鼠肾纤维化的作用和机制。方法:将大鼠随机分为5组,假手术组5只,模型组、HKC低剂量(L-HKC)组、HKC高剂量(H-HKC)组、硫辛酸(lipoic acid,LA)组各7只。采用单侧肾切除联合2次腹腔注射链脲佐菌素(streptozotocin,STZ)建立DN模型。造模成功后,HKC组、硫辛酸组大鼠分别经灌胃给予HKC悬浊液(0.75,2 g·kg-1)或硫辛酸(60 mg·kg-1),模型组大鼠也同时经灌胃给予2 m L蒸馏水,每天1次,连续8周。各组大鼠自给药开始计时,第8周末处死,采集血液和肾组织,观察HKC对尿白蛋白、肾功能、肾纤维化形态特征以及氧化应激(oxidative stress,OS)相关指标、p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)信号通路关键信号分子、致纤维化细胞因子以及炎症因子蛋白表达水平的影响。结果:HKC改善模型鼠一般情况、体重、尿白蛋白(urinary albumin,UAlb)、血清尿素氮(blood urea nitrogen,BUN)、尿酸(uric acid,UA)、白蛋白(albumin,Alb),其效果与硫辛酸相仿;HKC改善模型鼠肾纤维化,以高剂量HKC效果为显著,而且,其抗纤维化作用优于硫辛酸;HKC改善模型鼠肾组织OS主要指标,其效果与硫辛酸相似;HKC下调模型鼠肾组织磷酸化p38MAPK(phosphorylated-p38MAPK,p-p38MAPK)蛋白表达水平,降低转化生长因子(transforming growth factor,TGF)-β1、肿瘤坏死因子(tumor necrosis factor,TNF)-α蛋白表达水平,而硫辛酸只能抑制肾组织TNF-α蛋白表达水平。结论:对于DN模型鼠,HKC和硫辛酸一样,在体内具有拮抗肾组织OS损伤的作用;HKC与硫辛酸不一样,通过抑制肾组织p38MAPK信号通路活性以及致纤维化细胞因子、炎症因子蛋白表达水平,改善肾纤维化。     

电针“内关”对心肌肥厚模型大鼠p38丝裂原激活蛋白激酶信号通路的影响

目的:探讨电针“内关”穴治疗心肌肥厚的作用机制.方法:SD大鼠40只用随机数字表法分为正常组、模型组、模型+p38抑制剂组、模型十电针组,每组10只.采用皮下注射盐酸异丙肾上腺素3 mg/(kg·d)建立心肌肥厚大鼠模型,模型+p38抑制剂组在造模基础上每日皮下注射0.3 mg/kg p38丝裂原激活蛋白激酶(p38 MAPK)特异性抑制剂SB 203580;模型十电针组电针“内关”穴,采用连续波,频率2 Hz,强度1 mA,通电20 min,1次/d,共14 d.其他两组不予治疗干预.放射免疫法技术检测心肌组织肿瘤坏死因子-α(TNF-α)和白细胞介素-1β(IL-1β)含量,免疫印迹法检测p38MAPK、磷酸化p38 MAPK(p-p38 MAPK)含量.观察电针“内关”穴对TNF-α和IL-1β、p38 MAPK、p-p38 MAPK的影响.结果:与正常组大鼠比较,模型组大鼠TNF-α和IL-1β、p38 MAPK、p-p38 MAPK均显著升高(均P＜0.01);经抑制剂和电针处理后,模型+p38抑制剂组和模型十电针组大鼠TNF-α、IL-1β、p38 MAPK、p-p38 MAPK均明显降低,与模型组比较差异有统计学意义(均P＜0.05),与正常组比较差异亦有统计学意义(P＜0.05,P＜0.01);模型+p38抑制剂组和模型十电针组之间比较差异无统计学意义(P＞0.05).结论:电针“内关”可以明显抑制心肌肥厚p38 MAPK的磷酸化,这种保护作用可能通过抑制TNF-α、IL-1β等炎性因子的表达实现对p38 MAPK信号通路调节.     

Therapeutic Effect of Rhizoma Dioscoreae Nipponicae on Gouty Arthritis Based on the SDF‐1/CXCR 4 and p38 MAPK Pathway: An In Vivo and In Vitro Study

Rhizoma Dioscoreae Nipponicae (RDN) is a widely used traditional Chinese herb, which is used to treat arthroncus, arthrodynia and arthritis. As is known to us, inflammatory mechanisms have played an important role in the occurrence, course and prognosis of gouty arthritis (GA). The aim of this study was to determine the characteristic expressed proteins of synovium in GA rat and synovial cell. The rat model of GA was induced by monosodium urate (MSU) crystal. Tissue samples were assayed by immunohistochemical method. The effects of RDN on Stromal cell‐derived factor 1 (SDF‐1), CXCR 4 and p38 mitogen‐activated protein kinase (MAPK) were investigated in MSU crystal‐induced rat. The levels of SDF‐1 and mitogen‐activated kinase kinase (MKK) 3/6 were measured by Western Blot in interleukin‐1β (IL‐1β) incubated fibroblast‐like synoviocytes (FLS). A significant increase in the levels of SDF‐1, CXCR 4 and p38 MAPK were observed in MSU crystal‐induced rat. The increased SDF‐1 and MKK 3/6 levels were observed in IL‐1β incubated FLS. With the treatment of RDN, the above changes were reverted back to near normal levels. RDN might have some therapeutic effects on GA through SDF‐1/CXCR 4 and p38 MAPK pathway, and dioscin may be the active compound in RDN to exert therapeutic effect on GA. Copyright © 2013 John Wiley & Sons, Ltd.     

1,7‐Bis(4‐hydroxyphenyl)‐4‐hepten‐3‐one from Betula platyphylla induces apoptosis by suppressing autophagy flux and activating the p38 pathway in lung cancer cells

Betula platyphylla (BP) is frequently administered in the treatment of various human diseases, including cancers. This study was undertaken to investigate the pharmacological function of the active components in BP and the underlying mechanism of its chemotherapeutic effects in human lung cancer cells. We observed that BP extracts and 1,7‐bis(4‐hydroxyphenyl)‐4‐hepten‐3‐one (BE1), one of the components of BP, effectively decreased the cell viability of several lung cancer cell lines. BE1‐treated cells exhibited apoptosis induction and cell cycle arrest at the G2/M phase. Further examination demonstrated that BE1 treatment resulted in suppression of autophagy, as evidenced by increased protein expression levels of both LC3 II and p62/SQSTM1. Interestingly, the pharmacological induction of autophagy with rapamycin remarkably reduced the BE1‐induced apoptosis, indicating that apoptosis induced by BE1 was associated with autophagy inhibition. Our data also demonstrated that BE1 exposure activated the p38 pathway resulting in regulation of the pro‐apoptotic activity. Taken together, we believe that BE1 is a potential anticancer agent for human lung cancer, which exerts its effect by enhancing apoptosis via regulating autophagy and the p38 pathway.     

Ampelopsin inhibits high glucose‐induced extracellular matrix accumulation and oxidative stress in mesangial cells through activating the Nrf2/HO‐1 pathway

Oxidative stress plays an important role in diabetic nephropathy (DN), which is a diabetic complication. Ampelopsin (AMP) is a natural flavonoid that has been found to possess antidiabetic and antioxidative activities. However, the effect of AMP on DN remains unclear. In this study, we aimed to evaluate the protective effect of AMP on glomerular mesangial cells (MCs) exposed to high glucose (HG). We found that AMP improved HG‐caused cell viability reduction in MCs. AMP significantly suppressed the intracellular ROS production and expression levels of ROS producing enzymes NADPH oxidase 2 (NOX2) and NOX4. Increased of NOX activity in HG‐stimulated MCs was suppressed by AMP. Pretreatment with AMP inhibited extracellular matrix (ECM) accumulation in HG‐stimulated MCs with decreased expression levels of fibronectin (FN) and collagen type IV (Col IV). Furthermore, AMP elevated the expression levels of nuclear Nrf2 and heme oxygenase‐1 (HO‐1), as well as increased the mRNA levels of Nrf2‐driven genes NAD(P)H dehydrogenase quinone‐1 (NQO‐1) and HO‐1 in HG‐treated MCs. Knockdown of Nrf2 reversed the protective effects of AMP against HG‐induced oxidative stress and EMC accumulation in MCs. In conclusion, these findings indicated that AMP protected MCs from HG‐induced oxidative damage and ECM accumulation, which might be mediated by Nrf2/HO‐1 pathway.     

Huang-Lian-Jie-Du-Decotion induced protective autophagy against the injury of cerebral ischemia/reperfusion via MAPK-mTOR signaling pathway

Ethnopharmacological relevance

Huang-Lian-Jie-Du-Decotion (HLJDD, Hwangryun-Hae-Dok-Decotion in Japan), an ancient antipyretic and detoxifying traditional Chinese medicine formula, was reported to have protective effect on ischemic stroke.

Aim of the research

To investigate the therapeutic effect of HLJDD on ischemic stroke and explore its mode of action.

Material and methods

A model of ischemic stroke in the rat was established after transient middle cerebral artery occlusion (MCAO) followed by reperfusion. Rats were assigned randomly to groups of control, sham, transient ischemia/reperfusion (I/R), and three treatment groups by HLJDD at 2.5, 5.0, 10.0 mg/kg. The neurological deficit, the cerebral infarct size, morphology abnormality, biochemical parameters were examined, and the levels of relevant proteins were determined by immunoblotting analysis to evaluate the protective effects of HLJDD on ischemic stroke and explore the underlying mechanism.

Results

Compared with I/R group, HLJDD significantly ameliorated neurological deficit and histopathology changes, decreased infarct area, and restored the levels of biochemical indicators including nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), glutathione disulfide (GSSG), total superoxide dismutase (T-SOD), Cu/Zn-SOD, Mn-SOD and glutathione peroxidase (GSH-PX). HLJDD also notably elevated the levels of microtubule-associated protein1 light chain 3 (LC3), Beclin-1, and other autophagy related genes (Atgs), promoted the activation of extracellular signal-regulated kinases (ERK), protein kinase B (Akt), 3-phosphoinositide-dependent kinase (PDK1), and inhibited the activation of mammalian target of rapamycin (mTOR), c-Jun N-terminal protein kinases (JNK), p38, phosphatase and tensin homolog (PTEN).

Conclusion

HLJDD showed neuroprotective effects on ischemic stroke, at least in part to the induced protective autophagy via the regulation of mitogen-activated protein kinase (MAPK) signals. This Akt-independent protective autophagy is favorable in the treatment of stroke, avoiding unfavorable side-effects associated with the inactivation of Akt. The efficacy of HLJDD on ischemic stroke and its safety warranted by its long-term clinical use in traditional Chinese medicine favored further study to develop HLJDD as an effective therapeutic agent to treat ischemic stroke.