Efficacy of stem cell-based therapies for colistin-induced nephrotoxicity

The increase in infections with multidrug resistant bacteria has forced to return to the use of colistin, antibiotic with known nephrotoxicity. Mesenchymal stem cells (MSCs) are being extensively investigated for their potential in regenerative medicine. This study aimed to investigate the possible protective mechanisms of the MSCs against kidney injury induced by colistin. Forty adult female albino rats were randomly classified into 4 equal groups; the control group, the MSC-treated group (a single dose of 1 ×10⁶ /ml MSCs through the tail vein), the colistin-treated group (36 mg/kg/day colistin was given for 7 days), and the both colistin and MSC group (36 mg/kg/day colistin and 1 ×10⁶ /ml MSCs). Main outcome measures were histopathological alterations, kidney malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and immunohistological autophagy evaluation. MSC repressed the progression of colistin-induced kidney injury as evidenced by the improvement of histopathological alterations and the substantial increase MDA, and decrease SOD and CAT in serum levels. Moreover, MSC resulted in a profound reduction in oxidative stress as manifested by decreased MDA and increased SOD in serum. Notably, MSC suppressed colistin-induced autophagy; it reduced renal levels of Beclin-1, P62 and LC3A/B. Furthermore, MSC decreased renal levels of eNOS. Lastly, MSC efficiently decreased expression of the TUNEL positive cell number. MSC confers protection against colistin-induced kidney injury by alleviating oxidative stress, nitric oxide synthase besides modulating reducing autophagy and apoptosis.     

Shikonin from Chinese herbal medicine induces GSDME-controlled pyroptosis in tumor cells

ObjectiveTo investigate the potential anti-tumor mechanisms of naphthoquinone compound shikonin (SKN) extracted from the root of Chinese herbal medicine plant lithospermum (Lithospermum erythrorhizon Sieb. & Zucc.).MethodsWe first observed that SKN treatment led to swelling and bubbles in HeLa cells that were similar to the phenotype of cell pyroptosis. Subsequently, the HeLa cells experienced a pyroptotic process with SKN, and this was then assessed using lactate dehydrogenase (LDH) release and propidium iodide (PI)/Hoechst double staining experiments. Pyroptosis is defined as gasdermin-mediated programmed necroptosis. To identify the potential pyroptosis machinery, two strategies were utilized that included a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 screening experiment and a pyroptosis reconstitution assay executed by each of the five known gasdermins (GSDMA-E). Moreover, endogenous cleavage was also detected in a panel of tumor cell lines.ResultsCompared with the control, both the LDH release and PI/Hoechst double-staining experiments suggested that SKN induced perforation and enhancement of the permeability of the cell membranes that resulted in pyroptosis in HeLa cells (P = .028 and P = .032, respectively). In addition, the reconstitution assays in human embryonic kidney 293T (HEK-293T) cells and endogenous cleavage assays in HeLa cells indicated that the pyroptosis was controlled by GSDME. In addition, we also found SKN could trigger pyroptosis in a panel of tumor cell lines in which the cellular morphologies were proportional to the GSDME expression levels. Additionally, the cleavage of GSDME was also detected, and this was indicative of a similar GSDME-mediated mechanism.ConclusionOur study not only explained the molecular mechanism of cytotoxicity of SKN to various tumor cells, but also provided additional information for the potential clinical application of natural naphthoquinone compounds against cancer.     

IL-37b作用于树突状细胞CD39/ATP轴抑制类风湿性关节炎大鼠炎症反应的作用及机制

目的探讨白细胞介素37b重组蛋白(rmIL-37b)通过调节CD39/ATP轴抑制树突状细胞(DC)诱导类风湿性关节炎(RA)大鼠炎症反应的机制。方法将SD大鼠随机分为空白对照组(CTL)、CIA模型组、rmIL-37b 5μg/kg组、rmIL-37b 10μg/kg组,每组各10只。除了空白对照组外,其余大鼠采用含有卡介苗的完全弗氏佐剂和牛Ⅱ型胶原混合乳液免疫刺激,建立CIA模型。确定建模成功当天(D0),rmIL-37b组分别尾静脉注射5μg/kg、10μg/kg rmIL-37b;CTL组和CIA模型组注射相同体积的(1 ml/kg)生理盐水,连续给药15 d。免疫组化法检测滑膜组织Nod样受体蛋白3(NRPL3)炎症小体的表达,流式细胞术检测DC表型,另外试剂盒检测血清三磷酸腺苷(ATP)和免疫学指标。结果与CIA模型组相比,rmIL-37b 10μg/kg组大鼠足容积、AI值、NLRP3炎症小体表达量、血清ATP、IL-1β、IL-18、肿瘤坏死因子α(TNF-α)、抗Ⅱ型胶原抗体亚型(anti-ColⅡ-IgG、anti-ColⅡ-IgG2a)水平均降低,同时DC表面CD...     

外柱细胞软化对Corti器感音影响的生物力学研究

Corti器的感音过程容易受到内部结构属性变化的影响。外柱细胞血管舒张刺激磷蛋白缺失会减缓肌动蛋白丝的形成,从而产生听力延迟。本研究运用COMSOL建立三维有限元模型研究肌动蛋白缺失导致外柱细胞软化时,Corti器感音过程中基底膜和外毛细胞与Deiters细胞结合点的力学行为变化。结果表明,外柱细胞软化会削弱外毛细胞主动力对基底膜位移增益的放大作用,但削弱作用并不会立即产生,Corti器存在维持正常功能的"缓冲"阶段。在100 dB和120 dB之间可能存在一个声压级临界值,在该临界值两侧外柱细胞软化对基底膜应力变化的影响是截然相反的。另外外柱细胞软化对不同外毛细胞与Deiters细胞结合点力学行为的影响也不同,位移增益优先级会因此产生改变。     

Potentilla anserine L. polysaccharide protects against cadmium-induced neurotoxicity

Cadmium is a toxic metal that can damage the brain and other organs. This study aimed to explore the protective effects of Potentilla anserine L. polysaccharide (PAP) against CdCl₂-induced neurotoxicity in N2a and SH-SY5Y cells and in the cerebral cortex of BALB/c mice. In addition, we aimed to identify the potential mechanisms underlying these protective effects. Relative to CdCl₂ treatment alone, pretreatment with PAP prevented the reduction in cell viability evoked by CdCl₂, decreased rates of apoptosis, promoted calcium homeostasis, decreased ROS accumulation, increased mitochondrial membrane potential, inhibited cytochrome C and AIF release, and prevented the cleavage of caspase-3 and PARP. In addition, PAP significantly decreased the CdCl₂-induced phosphorylation of CaMKII, Akt, and mTOR. In conclusion, PAP represents a potential therapeutic agent for the treatment of Cd-induced neurotoxicity, functioning in part via attenuating the activation of the mitochondrial apoptosis pathway and the Ca²⁺-CaMKII-dependent Akt/mTOR pathway.     

Induction of tumor cell autosis by myxoma virus-infected CAR-T and TCR-T cells to overcome primary and acquired resistance

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大黄附子汤对重症急性胰腺炎小鼠肠道微皱褶细胞变化的影响

目的研究大黄附子汤对重症急性胰腺炎(SAP)小鼠肠道微皱褶细胞(M细胞)变化的影响，为大黄附子汤临床防治SAP提供理论基础。 方法选取40只健康SPF级C57BL/6J雄性小鼠，随机分为4组(每组10只)：空白对照组、大黄附子汤对照组、SAP组、大黄附子汤治疗组，其中SAP组和大黄附子汤治疗组分别以3.5 g/kg剂量腹腔注射20% L-精氨酸，空白对照组和大黄附子汤对照组注射等剂量的等渗盐水；于造模后12、24、36 h，空白对照组和SAP组给予等渗盐水0.2 mL，大黄附子汤对照组和治疗组给予大黄附子汤0.2 mL灌肠，均于造模完成48 h后处死取材，使用ELISA检测血清淀粉酶、内毒素、IL-1β及TNF-α含量，取回肠及胰腺组织行HE染色、评分，免疫组化染色检测M细胞特异性蛋白GP2并评分。 结果(1)一般情况：对照组腹腔注射后小鼠一般情况好，精神状态良好，能正常进水，四肢活动自如，行动未受影响；SAP组小鼠腹腔注射后一般情况差，精神萎靡，反应迟钝，行动迟缓，呼吸急促，拱背收腹，饮水减少。(2)SAP组淀粉酶、内毒素、IL-1β及TNF-α水平较对照组明显升高(P<0.05)；与SAP组进行对比，大黄附子汤治疗组血清淀粉酶、内毒素、IL-1β及TNF-α水平出现显著下降(P<0.05)。(3)HE染色：SAP组胰腺及回肠组织坏死严重，可见大量白细胞浸润。大黄附子汤治疗组胰腺及回肠组织轻度坏死，可见少量中性粒细胞等白细胞浸润。(4)免疫组化染色：SAP组与对照组相比GP2表达降低(P<0.05)；相较于SAP组，大黄附子汤治疗组GP2的表达水平升高(P<0.05)。 结论大黄附子汤治疗可改善作为肠道免疫应答起始的M细胞数量与功能，增强肠道免疫应答，减轻肠免疫屏障损伤，减少内毒素入血，改善SAP症状。     

温阳解郁颗粒调节BDNF/TrkB/ERK信号通路保护皮质酮诱导损伤型海马神经细胞的作用机制研究＊

目的 观察温阳解郁颗粒（Wenyang Jieyu granule，WYJY）对皮质酮（Corticosterone，CORT）诱导损伤型小鼠海马神经细胞（TH22 cell）的保护作用，基于脑源性神经营养因子（Brain derived neurotrophic factor， BDNF）/酪氨酸激酶B（Tyrosine kinase B， TrkB）/细胞外信号调节蛋白激酶（Extra cellular regulated protein kinases， ERK）信号通路探讨WYJY保护海马神经细胞的作用机制。方法 体外构建小鼠海马神经细胞皮质酮诱导损伤模型，以不同浓度的WYJY和氟西汀（Fluoxetine，FXT）含药血清作用于模型细胞，细胞增殖-毒性检测（Cell Counting Kit-8， CCK-8）法分析细胞活性，倒置显微镜下观察给药前后细胞形态结构的改变，采用蛋白免疫印迹法（Western Blot）、实时荧光定量PCR（Quantitative real-time PCR， qPCR）法检测神经细胞内凋亡因子（BCL2-Associated X， Bax）、抗凋亡因子（B-cell lymphoma-2， Bcl-2）、BDNF、Trkb、ERK以及丝氨酸/苏氨酸激酶（Phospho-p90RSK， RSK）、环磷腺苷效应元件结合蛋白（cAMP-response element binding protein， CREB）蛋白表达水平以及相关基因的表达水平。结果 在浓度为459.5 μmol·L^-1的CORT作用24 h后，HT22细胞的活性抑制率达到50%，在此条件作用下细胞形态结构损伤明显，凋亡程度严重，细胞上清中BDNF的含量显著减少（P<0.05），细胞内凋亡相关因子Bax/Bcl-2的比值明显升高（P<0.01），BDNF、Trkb、ERK、RSK、CREB磷酸化蛋白表达水平和mRNA表达水平明显降低（P<0.01）；以5%的浓度为2.85 g·kg^-1的WYJY和10%的FXT含药血清作用于受损的HT22细胞后，HT22细胞存活率明显提升（P<0.01），细胞结构的损伤明显改善，细胞凋亡程度减轻，细胞外BDNF的含量显著升高（P<0.05），细胞内Bax/Bcl-2比值显著下调（P<0.01），BDNF、Trkb、ERK、RSK、CREB磷酸化蛋白表达水平和mRNA表达水平显著提升（P<0.05，P<0.01）。结论 温阳解郁颗粒可有效保护高浓度CORT造成的小鼠海马神经细胞损伤。调控BDNF/Trkb/ERK通路，放大CREB信号传导，影响Bcl-2、BDNF水平，可能是其保护海马神经元，发挥抗抑郁疗效的重要机制。     

Tumor-induced erythroid precursor-differentiated myeloid cells mediate immunosuppression and curtail anti-PD-1/PD-L1 treatment efficacy

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