A role of GCC88 in the retrograde transport of CI‐M6PR and the maintenance of lysosomal activity

GCC88 is a golgin coiled‐coil protein at the trans‐Golgi (TGN) that functions as a tethering factor for the endosome‐derived retrograde transport vesicles. Here, we demonstrate that GCC88 is required for the endosome‐to‐TGN retrograde transport of the cation‐independent mannose 6‐phosphate receptor (CI‐M6PR). The knockout of GCC88 perturbs the retrieval of CI‐M6PR and decreases its cellular level at the steady state, which causes the improper processing of newly synthesized cathepsin‐D, a lysosomal hydrolase dependent on CI‐M6PR for its delivery to lysosomes. At the whole cell level, the knockout of GCC88 reduces the lysosomal proteolytic capacity but does not impair of the efficiency of autophagy within these cells.     

Hydroxytyrosol prevents dermal papilla cells inflammation under oxidative stress by inducing autophagy

Hydroxytyrosol (HT), a primary phenolic antioxidant in olive oil, can afford protection from oxidative stress (OS) in different cells, including skin cells. In particular, it regulates several inflammation‐associated processes as well as in improving the antioxidant defense system. However, there is no information about HT used in the treatment of hair loss. This work aimed at exploring the potential protective actions of HT against OS in rat dermal papilla cells. After treatment, the related expression of protein and messenger RNA were detected using morphological and molecular analyses. The results showed that HT significantly reduced intracellular reactive oxygen species level, apoptotic markers and inflammation induced by OS and enhanced cell survival by regulating autophagy. Furthermore, HT enhanced the secretion of hair growth factors in the anti‐inflammation process. These results suggest that HT has a significant protective ability against OS and encourage the use of this biological ingredient as a possible tool to prevent alopecia.     

Hydrogen sulfide alleviates uranium‐induced rat hepatocyte cytotoxicity via inhibiting Nox4/ROS/p38 MAPK pathway

As a gasotransmitter, hydrogen sulfide (H₂S) plays a crucial role in regulating the signaling pathway mediated by oxidative stress. The purpose of this study was to investigate the protective effects of H ₂S on uranium‐induced rat hepatocyte cytotoxicity. Primary hepatocytes were isolated and cultured from Sprague Dawley rat liver tissues. After pretreating with sodium hydrosulfide (an H ₂S donor) for 1 hour (or GKT‐136901 for 30 minutes), hepatocytes were treated by uranyl acetate for 24 hours. Cell viability, reactive oxygen species (ROS), malondialdehyde (MDA), NADPH oxidase 4 (Nox4), and p38 mitogen‐activated protein kinase (p38 MAPK) phosphorylation were respectively determined. The effects of direct inhibition of Nox4 expression by GKT‐136901 (a Nox4 inhibitor) on ROS and phospho‐p38 MAPK levels were examined in uranium‐treated hepatocytes. The results implicate that H ₂S can afford protection of rat hepatocytes against uranium‐induced adverse effects through attenuating oxidative stress via prohibiting Nox4/ROS/p38 MAPK signaling.     

The RNase PARN Controls the Levels of Specific miRNAs that Contribute to p53 Regulation

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南麂列岛东侧海域主要游泳动物生态位及种间联结性

根据2017年秋季和2018年春季在南麂列岛东侧海域进行的渔业资源调查所获数据,应用相对重要性指数、生态位宽度、聚类分析、生态位重叠值、基于2×2数据矩阵的χ²检验、方差比率、联结系数、共同出现百分率和点相关系数等,分析了主要游泳动物的种间关系和生态联系.结果表明: 在调查的30种主要游泳动物中,优势种有龙头鱼、三疣梭子蟹和口虾蛄3种,它们的生态位宽度较宽.采用生态位宽度聚类分析,可以将主要游泳动物划分为广生态位种、中生态位种和狭生态位种3个类型.生态位重叠值分布区间为[0, 0.98],说明物种对资源利用的相似性存在差异,生态位出现分化并伴随种间竞争现象.根据方差比率和W检验得出主要游泳动物间总体为显著正相关.χ²检验结果显示,联结性显著的有76个种对(χ²≥3.841),这与群落结构稳定性、物种共存现象存在一定关联.联结系数(AC)、共同出现百分率和点相关系数检验结果表明,物种间联结性较强,总体趋于正相关关系.     

利用黑斑双鳍电鳐构建实验性自身免疫性重症肌无力小鼠模型

目的建立符合国际化的临床前实验标准的实验性自身免疫性重症肌无力(experimental autoimmune myasthenia gravis, EAMG)动物模型。方法参照文献报道的方法并改进后,从电鳐电器官提取乙酰胆碱受体(acetylcholine receptor,AchR)蛋白纯品,并采用SDS凝胶电泳蛋白定性鉴定及BCA法蛋白定量;用纯化的蛋白主动免疫C57BL/6小鼠,共免疫3次(分别于第1天、第30天、第60天),进行EAMG小鼠临床评分、体重、血清AchR抗体含量、新斯的明试验、肌电图等综合评价。结果 EAMG模型组与佐剂组比较,自第三周开始发病,平均临床评分显著上升(P<0.01);发病小鼠体重显著减轻(P<0.01);新斯的明试验阳性;血清AchR抗体含量明显增加(P<0.01);肌电图重复电刺激实验阳性。结论从黑斑双鳍电鳐的电器官提取、纯化AchR蛋白成功诱导C57BL/6 EAMG小鼠模型,为进一步研究重症肌无力创造了良好条件。     

离体诱变定向培育高油花生新品种宇花9号

笔者前期研究发现经干旱胁迫处理后的花生叶片水势与其籽仁含油率呈显著正相关。文中对羟脯氨酸作为水势(渗透压)调节物质用于离体定向筛选花生高油突变体及培育花生新品种进行了研究。以花生品种花育20号胚小叶作为外植体,平阳霉素作为诱变剂添加于体胚诱导培养基上进行离体诱变培养。形成的体胚转移到添加6 mmol/L羟脯氨酸(培养基水势为-2.079 MPa)的体胚萌发和再生培养基上诱导体胚萌发成苗,同时进行高油突变体定向筛选。再生小苗经嫁接移栽田间,从再生植株后代中获得了132份含油率55%以上的高油突变体,其中27份含油率超过58%,2份超过60%。再生植株后代结合系谱育种法育成了高产高油花生新品种宇花9号,在辽宁省花生新品种备案试验中,籽仁产量比对照品种增产14.0%,并通过了国家非主要农作物品种登记。宇花9号含油率达61.05%,比亲本花育20号高11.55个百分点,是目前国际上含油率最高的花生品种。本研究结果表明,利用离体诱变、培养基低水势定向筛选及其再生植株后代结合常规育种法选择是定向培育高油花生品种的有效方法。