Peptides YYGGEGSSSEQG and SESEM Inhibit TNF-α-Induced Smooth Muscle Cells Proliferation and Migration Through Their Bindings to TNF-α Receptor

International Journal of Peptide Research and Therapeutics - The peptides YYGGEGSSSEQG and SESEM derived from rice α-globulin have been reported to possess anti-atherosclerotic activity, but...     

Gentiopicroside promotes the osteogenesis of bone mesenchymal stem cells by modulation of β-catenin-BMP2 signalling pathway

Osteoporosis is characterized by increased bone fragility, and the drugs used at present to treat osteoporosis can cause adverse reactions. Gentiopicroside (GEN), a class of natural compounds with numerous biological activities such as anti-resorptive properties and protective effects against bone loss. Therefore, the aim of this work was to explore the effect of GEN on bone mesenchymal stem cells (BMSCs) osteogenesis for a potential osteoporosis therapy. In vitro, BMSCs were exposed to GEN at different doses for 2 weeks, whereas in vivo, ovariectomized osteoporosis was established in mice and the therapeutic effect of GEN was evaluated for 3 months. Our results in vitro showed that GEN promoted the activity of alkaline phosphatase, increased the calcified nodules in BMSCs and up-regulated the osteogenic factors (Runx2, OSX, OCN, OPN and BMP2). In vivo, GEN promoted the expression of Runx2, OCN and BMP2, increased the level of osteogenic parameters, and accelerated the osteogenesis of BMSCs by activating the BMP pathway and Wnt/β-catenin pathway, effect that was inhibited using the BMP inhibitor Noggin and Wnt/β-catenin inhibitor DKK1. Silencing the β-catenin gene and BMP2 gene blocked the osteogenic differentiation induced by GEN in BMSCs. This block was also observed when only β-catenin was silenced, although the knockout of BMP2 did not affect β-catenin expression induced by GEN. Therefore, GEN promotes BMSC osteogenesis by regulating β-catenin-BMP signalling, providing a novel strategy in the treatment of osteoporosis.     

Hydrogen sulphide reduces hyperhomocysteinaemia-induced endothelial ER stress by sulfhydrating protein disulphide isomerase to attenuate atherosclerosis

Hyperhomocysteinaemia (HHcy)-impaired endothelial dysfunction including endoplasmic reticulum (ER) stress plays a crucial role in atherogenesis. Hydrogen sulphide (H₂S), a metabolic production of Hcy and gasotransmitter, exhibits preventing cardiovascular damages induced by HHcy by reducing ER stress, but the underlying mechanism is unclear. Here, we made an atherosclerosis with HHcy mice model by ApoE knockout mice and feeding Pagien diet and drinking L-methionine water. H₂S donors NaHS and GYY4137 treatment lowered plaque area and ER stress in this model. Protein disulphide isomerase (PDI), a modulation protein folding key enzyme, was up-regulated in plaque and reduced by H₂S treatment. In cultured human aortic endothelial cells, Hcy dose and time dependently elevated PDI expression, but inhibited its activity, and which were rescued by H₂S. H₂S and its endogenous generation key enzyme-cystathionine γ lyase induced a new post-translational modification-sulfhydration of PDI. Sulfhydrated PDI enhanced its activity, and two cysteine-terminal CXXC domain of PDI was identified by site mutation. HHcy lowered PDI sulfhydration association ER stress, and H₂S rescued it but this effect was blocked by cysteine site mutation. Conclusively, we demonstrated that H₂S sulfhydrated PDI and enhanced its activity, reducing HHcy-induced endothelial ER stress to attenuate atherosclerosis development.     

Impact of left atrial appendage location on risk of thrombus formation in patients with atrial fibrillation

Biomechanics and Modeling in Mechanobiology - Most strokes in patients with atrial fibrillation (AF) are thought to arise from thrombus formation in the left atrial appendage (LAA). Assessing the...     

土壤氮磷添加下豆科草本植物生物固氮与磷获取策略的权衡机制

豆科草本植物固氮是陆地生态系统重要的自然氮输入方式, 影响着草地生产的经济性和可持续性。为探讨氮磷交互作用影响豆科草本植物生物固氮率的潜在生理生态机制, 该研究选取8种豆科草本植物分别种植在对照、氮肥添加、磷肥添加和氮磷耦合添加处理的土壤中, 进行野外盆栽实验。测定了初花期植物生物量和营养含量、根部碳水化合物含量、根际pH、根际柠檬酸含量、根际有效磷含量、植物根瘤生物量、磷含量及其生物固氮率。主要结果: 依赖于豆科物种, 氮添加显著促进了豆科草本植物根际磷的活化, 降低了根生物量分配以及根系非结构性碳水化合物含量。在两种磷添加处理下, 氮添加导致8种豆科草本植物根瘤生物量平均下降27%-36%, 生物固氮率平均下降20%-33%。磷添加降低了根际的磷活化, 但促进了豆科草本植物根系发育和非结构性碳水化合物的积累。在施氮和不施氮条件下, 磷添加分别使8种豆科草本植物的生物固氮率提高了45%-69%和0-47%。氮添加降低豆科草本植物生物固氮率, 其原因是氮添加提高了植物磷需求, 为活化更多磷, 豆科草本植物降低根系生物量和根系非结构性碳水化合物的含量, 导致根瘤发育受到限制。在氮添加的同时进行磷添加, 能够改善土壤氮磷平衡, 促进根系生长和非结构性碳水化合物积累, 缓解了增氮对生物固氮的抑制作用。     

不同管理模式对茶树碳氮磷含量及其生态化学计量比的影响

植物不同器官的碳(C)、氮(N)、磷(P)含量及其生态化学计量特征能够反映植物内部的养分分配与平衡关系。该研究以福建安溪3种不同管理模式的铁观音茶园为研究对象, 设置了常规管理模式下的茶园(M1)、间作套种模式下的茶园(M2)和现代技术管理模式下的茶园(M3) 3种样地, 分析茶树根、茎、叶器官的C、N、P含量及其化学计量学特征, 养分的变异特征与异速生长关系。结果表明: M2和M3管理模式下茶树根、茎、叶N、P含量均显著高于M1管理模式, C含量差异不明显; 茶树根、茎、叶C:N、C:P、N:P均表现为M1 > M2 > M3。茶树不同器官C、N、P含量差异较大, 根据变异来源分析, 管理模式因素对C、N、P含量变异的影响均达到显著水平。根茎叶N-P的异速生长关系表明茶树不同器官的养分需求存在相似性; 土壤pH和容重是影响C:N、C:P、N:P的重要因素, 而土壤含水量和盐度对茶树根和叶C含量的影响较大。总体来讲, 间作套种以及现代化滴灌、水肥等管理模式可以改善茶树对养分的吸收效率, 对解决土壤养分不均衡问题具有正面效应。     

幽门螺杆菌根除治疗对消化性溃疡患者血清胃泌素水平的影响

目的观察幽门螺杆菌(H.pylori)根除治疗对消化性溃疡患者血清胃泌素水平的影响,为该病治疗提供参考。方法选择我院2017年8月至2019年8月收治的120例H.pylori感染的消化性溃疡患者作为观察组,根据H.pylori分型结果进一步分为HPⅠ型组和HPⅡ型组,观察组患者接受根除幽门螺杆菌治疗。选择同期入院的40例非幽门螺杆菌感染消化性溃疡患者作为对照组,对照组患者接受常规治疗。比较两组患者治疗效果、胃镜检查结果、H.pylori清除情况及血清胃泌素、IL-10、IL-17水平。结果HPⅠ型组、HPⅡ型组和对照组患者临床总有效率差异无统计学意义(92.75%、96.08%、97.50%,χ²=1.384,P=0.051)。HPⅠ型组、HPⅡ型组、对照组患者胃镜检查总有效率差异无统计学意义(91.30%,96.08%,97.50%,χ²=1.384,P=0.051)。HPⅡ型组患者幽门螺杆菌根除率高于HPⅠ型组(98.04%vs 85.51%,χ²=4.129,P=0.042)。HPⅠ型组患者治疗后血清胃泌素、IL-10、IL-17水平均高于对照组(均P<0.05)。HPⅠ型组患者治疗后血清IL-10、IL-17水平均高于HPⅡ型组(均P<0.05)。HPⅠ型组与HPⅡ型组患者治疗后血清胃泌素差异无统计学意义(t=1.918,P=0.058)。HPⅡ型组患者治疗后血清IL-10、IL-17水平均高于对照组(均P<0.05)。HPⅡ型组与对照组患者治疗后血清胃泌素差异无统计学意义(t=1.382,P=0.170)。结论不同类型H.pylori感染消化性溃疡患者行幽门螺杆菌根除治疗后临床效果无显著差异。幽门螺杆菌根除治疗可降低消化性溃疡患者血清胃泌素、IL-10、IL-17水平。     

贵州省藜芦科一新记录属——白丝草属

报道贵州省藜芦科一新记录属——白丝草属Chamaelirium Willd.,一新记录种——中国白丝草Chamaelirium chinense (K. Krause) N. Tanaka,并对该种的形态特征、生境、分类变动进行描述及讨论。     

Interacting effects of water temperature and dietary protein level on hematological parameters in Nile tilapia juveniles,Oreochromis niloticus (L.) and mortality under Streptococcus iniae infection

Based on central composite rotatable experimental design and response surface method, the interacting effects of temperature (20 °C–34 °C) and dietary protein level (25%–50%) on hematological parameters including red blood cell (RBC), white blood cell (WBC) and hemoglobin (Hb) of juvenile Oreochromis niloticus were studied under laboratory conditions. The experiment lasted for 7 weeks. After the feeding trial, fish were challenged with Streptococcus iniae and mortality was recorded for within 8 days. Results showed that the linear and quadratic effects of temperature on RBC, WBC and Hb were highly significant (P < 0.01). When the dietary protein level was 25%–50%, the RBC, WBC and Hb were increased firstly and then decreased, but the linear and quadratic effects of protein level were insignificant (P > 0.05). The interacting effects of temperature and protein level on RBC and Hb were significant (P < 0.05). The regression equations of RBC, WBC and Hb toward the two factors of interest were established, with the coefficients of determination being 0.870, 0.836 and 0.881, respectively (P < 0.01). These equations could be used for prediction in practice. After the challenge, the mortalities for the combinations of 22.1 °C/28.7% and 20.0 °C/37.5% were significantly higher than 27.0 °C/37.5% (P < 0.05). The optimal temperature/dietary protein level combination was obtained at 27.9 °C/38.1% at which the lowest mortality (13.76%) was attained. This value was close to the optimal temperature/dietary protein level combination (29.4 °C/41.9%) for the greatest levels of RBC (2.560 × 10⁶ μL^?1), WBC (270.648 × 10³ μL^?1) and Hb (92.851 g L^?1). The results of this study indicated that preferred temperature/dietary protein level combination might strengthen the non-specific immunity and reduce susceptibility to S. iniae.