草鱼神经肽Y受体对神经肽Y的响应机制及信号通路探究

为探究草鱼（Ctenopharyngodon idellus）神经肽Y（neuropeptide Y，NPY）与神经肽Y受体（NPY receptor，YR）的相互作用及信号传递机制，对草鱼YR的基因结构、组织表达和细胞信号传导途径进行分析。结果显示，在草鱼基因组中获取了7个YR基因的序列，分别为Y1R、Y2R、Y2-2R、Y4R、Y7R、Y8Ra和Y8Rb。对草鱼YR进行同源性分析，发现7个YR编码的氨基酸序列在硬骨鱼类中高度保守。组织表达结果显示，草鱼YR主要在中枢组织表达，但也可以位于外周组织，包括眼睛、鳃和肠道。NPY可以激活人胚胎肾细胞（HEK293t）中Y2R、Y4R和Y8Rb的表达，Y2R与cAMP/PKA信号通路偶联；Y4R与MAPK/ERK信号通路偶联；而Y8Rb可激活cAMP/PKA和MAPK/ERK 2条信号通路。脑室注射NPY可引起Y1R、Y2R、Y4R和Y8Rb表达量显著升高。研究结果表明，草鱼Y2R、Y4R和Y8Rb具有功能性，能够有效传递信号，NPY的作用很可能由这些受体介导。     

过氧化物酶体增殖物激活受体γ调控机体炎症信号通路的研究进展

过氧化物酶体增殖物激活受体γ(Peroxisome Proliferators-activated Receptorγ,PPARγ)是调控炎症反应的关键物质之一,其通过减弱核因子Kappa B(Nuclear Factor-kappa B,NF-κB)、c-Jun氨基末端激酶(c-Jun N-terminalKinase,JNK)活性,降低炎症因子含量从而缓解炎症反应,另一方面PPARγ与腺苷酸激活蛋白激酶(AMP-activated Protein Kinase,AMPK)互相抑制,共同维持动物正常机能。本文综述了PPARγ对动物炎症通路的调控作用,为其进一步研究和应用提供参考。     

MCC950 Improves Growth Performance, Ｕric Acid Metabolism and Kidney Injury of Goslings Fed High Protein Diet by Inhibiting Nucleotide Binding Oligomerization Domain-Like Receptor 3 Inflammasome北大核心CSCD

The aim of this study was to evaluate the effects of MCC950 on growth performance, uric acid metabolism, serum inflammatory factor contents and kidney injury of goslings a fed high protein diet, and explore the potential mechanism of nucleotide binding oligomerization domain-like receptor 3 (NLRP3) / cysteine aspartase-1 (Caspase-1) signaling pathway in gosling gout. A total of 120 Yangzhou goslings of 1-day-old were randomly divided into 3 groups, which were control group, high protein group (HP group) and high protein+ MCC950 group (HP+MCC950 group), with 5 replicates in each group and 8 goslings in each replicate. The control group was fed a normal protein diet with 16.5% crude protein, and the HP group and HP+MCC950 group were fed a high protein diet with 24.0% crude protein. The HP+MCC950 group was intraperitoneally injected with MCC950 every 3 days at a dose of 10 mg / kg BW, and the other two groups were injected with the same amount of normal saline. The experiment lasted for 15 days. The results showed as follows: 1) compared with the control group, the average body weight of goslings at 15 days of age in the HP group was significantly decreased (P<0.05); the serum contents of uric acid (UA), creatinine (Cr), urea nitrogen (UN), C-reactive protein (CRP), interleukin-1β (IL-1β), interleukin 18 (IL-18), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) and transforming growth factor β1 (TGF-β1) in the HP group were significantly increased (P<0.05); the mRNA relative expression levels of NLRP3, Caspase-1, IL-1β and IL-18 and the protein relative expression levels of NLRP3, Caspase-1 and IL-1β in kidney tissues in the HP group were significantly increased (P<0.05). 2) Compared with the HP group, the average body weight of goslings at 10 and 15 days of age in the HP+MCC950 group was significantly increased (P<0.05); the serum contents of UA, Cr, UN, CRP, IL-1β, IL-18, IL-6, TNF-α and TGF-β1 were significantly decreased (P<0.05), while the mRNA relative expression levels of NLRP3, Caspase-1, IL-1β and IL-18 and the protein relative expression levels of NLRP3, Caspase-1 and IL-1β in kidney tissues in the HP+MCC950 group were significantly decreased (P< 0.05). 3) Histological findings showed that the renal tubules of goslings were dilated, and vacuolar degeneration and necrosis occurred in the HP group, while the structure of renal tubules was relatively normal in the HP+MCC950 group. The urate deposition area in kidney tissues of goslings in the HP group was significantly larger than that in the control group (P<0.05), and which in the HP+MCC950 group was significantly smaller than that in the HP group (P<0.05). Moreover, the urate deposition area in kidney tissues of goslings was significantly positively correlated with the protein relative expression level of NLRP3 (r = 0.681, P<0.05). In conclusion, MCC950 can promote the growth of goslings fed a high protein diet and reduce the serum uric acid content, which may be related to the reduction of inflammatory response and kidney injury through its inhibition of NLRP3 / Caspase-1 signaling pathway. © 2023 Authors. All rights reserved.     

Wnt-LRP6信号通路激活REST蛋白的表达并发挥神经保护作用

为检测以LRP6受体为激活开关的Wnt-β-catenin信号通路与PrP106-126毒性多肽引起的神经元损伤之间的相互关系,并研究该信号通路与神经保护性蛋白REST的相关性,从而进一步阐明Wnt-LRP6-REST对毒性多肽引起的神经元损伤的影响。利用Wnt信号通路的激活剂Licl、抑制剂DKK1或PrP106-126毒性多肽刺激原代神经元,通过免疫印迹检测神经保护性蛋白REST及Wnt信号通路下游相关蛋白的变化情况,通过激光共聚焦观察REST与Wnt信号通路正相关蛋白β-catenin的共定位情况。分别构建LRP6的过表达质粒pCMV-C-HALRP和干扰质粒pGPH1/GFP/Neo-LRP6-Rat shRNA-1和shRNA-2,将已经构建好的质粒转染进入原代神经元。通过免疫印迹检测PrP106-126毒性多肽对Wnt信号通路标志性蛋白(β-catenin及GSK3β)的影响,检测LRP6的过表达或干扰对REST或Wnt信号通路下游蛋白的影响。通过免疫荧光观察LRP6对由毒性多肽诱导的神经纤维损伤的影响,用流式细胞仪检测相应的细胞活力。由LRP6受体激活的Wnt-β-catenin信号通路在一定程度上正向调控神经保护性蛋白REST的表达,LRP6在信号调节的过程中起到了关键作用,并且LRP6对由PrP106-126毒性多肽引起的神经元损伤有缓解作用,LRP6的过表达增加了神经元细胞的活力,起到了神经保护作用。     

Dietary high protein-induced diarrhea and intestinal inflammation by activation of NF-κB signaling in piglets

The present study aimed to investigate whether inflammation-associated responses in piglets are induced by high protein (HP) through activating nuclear factor kappa B (NF-κB) signaling. Sixteen piglets (35 d of age, Duroc × [Landrace × Yorkshire], weaned at d 21, initial BW = 9.70 ± 0.11 kg) were allocated to 18% and 26% CP (HP group) at random, comprising 8 replicate pens per treatment. The piglets were slaughtered to collect intestinal tissues when apparent, persistent, and stable diarrhea syndromes happened (on d 12). No significant differences were observed in their growth performance (P > 0.05), but reduction by 19.11%, 25.31%, 23.64% of ADFI, ADG, and G:F, respectively was detected in the HP group. The HP group had greater (P = 0.002) diarrhea rates. Furthermore, dietary HP had lower ileal villus height (VH; P = 0.048), ratio of villus height to crypt depth (VH/CD ratio; P = 0.016), and colonic CD (P = 0.034), as well as had the trend (P = 0.075) to reduce the ileal villus absorptive area. Moreover, HP diets significantly elevated the goblet cell numbers in the ileal villi (P = 0.016) and colonic crypts (P < 0.001) and up-regulated (P = 0.012) the mRNA expression of mucin2 (Muc2) in the ileum. In addition, HP diets increased the myeloperoxidase concentration in the ileum (P = 0.002) and colon (P = 0.007) of piglets. Dietary HP significantly down-regulated the mRNA expression of tumor necrosis factor-α (TNF-α; P < 0.001) in the ileum, induced nitric oxide synthase (iNOS; P = 0.040) and interleukin-22 (IL-22; P = 0.008) in the colon, and inclined to down-regulate interleukin-1β (IL-1β; P = 0.076) expression in the colon. The relative protein abundance of Galectin-3 (P = 0.046) in the colon and the ratio of phosphorylation NF-κB to NF-κB (p–NF–κB/NF-κB ratio) in the ileum of HP piglets were also greater (P = 0.038). These results suggest that dietary HP may cause diarrhea in piglets by activating NF-κB signaling induced intestinal inflammation.     

意大利蜜蜂Hippo信号通路相关基因及其全长转录本的鉴定与分析

采用Blast工具将已鉴定到的意大利蜜蜂(Apis mellifera ligustica，简称意蜂)全长转录本比对Nr数据库，共鉴定到意蜂Hippo信号通路中相关的49个基因及其550条全长转录本。运用Gffcompare软件将鉴定到的Hippo信号通路相关全长转录本与西方蜜蜂参考基因组(Amel_HAv3.1)上注释的转录本进行比较，分别延长西方蜜蜂参考基因组注释到Hippo信号通路的9个基因的5'' UTR和7个基因的3'' UTR。通过Astalavista软件鉴定到Hippo信号通路相关的4个基因的7次可变剪切(AS)事件，包括2次外显子跳跃、2次内含子保留和3次可变5''端剪接。通过PCR验证了1个基因的AS事件真实性。利用TAPIS pipeline鉴定到意蜂Hippo信号通路相关的24个基因含有1个及以上可变多聚腺苷酸化(APA)位点，其中含有1个APA位点的基因数量最多。通过TBtool软件鉴定APA位点上游motif的一致性序列HVNCCNBNDYVDVVHVNDBVDYCNBBDNNNHNNVNNVMNN。     

转录因子MYCs调控番茄表皮毛萜类化合物的分子机制研究进展

番茄是一种世界性种植的重要蔬菜作物,在种植过程中易受病虫害的影响,造成减产。表皮毛是番茄表面第一道关键的屏障,可增强番茄对生物和非生物胁迫的适应性。为了进一步研究表皮毛在番茄抗逆中的作用机理,本文归纳了番茄表皮毛内含物的种类及其分子调控机制,重点总结了JA信号途径中的核心转录因子MYC1和MYC2对番茄表皮毛萜类化合物合成调控的分子机制,并分析了当前表皮毛研究存在的问题,展望了表皮毛未来的研究方向。     

苦参碱对H9N2 AIV感染小鼠NLRP3炎性体信号通路的影响

【目的】流感病毒感染引发机体的炎症反应及免疫稳态失衡，由此产生的细胞因子风暴（CS）是引起感染宿主死亡的主要原因。通过探究苦参碱对H9N2 AIV感染小鼠的保护作用及其调节NLRP3炎性体信号通路的特点及作用机制，可进一步完善中药抗病毒的理论依据，为新型抗病毒药物的研发奠定基础。【方法】72只8周龄BALB/c小鼠随机分为空白组（0.1 mL无菌鸡胚尿囊液）、病毒组（0.1 mL 4×10⁵PFU/mLH9N2 AIV）、金刚烷胺组（0.1 mL 4×10⁵PFU/mLH9N2 AIV+100×10^-6 99%金刚烷胺）、苦参碱高浓度治疗组（0.1 mL 4×10⁵PFU/mLH9N2 AIV+40 mL·kg^-1苦参碱）、中浓度治疗组（0.1 mL 4×10⁵PFU/mLH9N2 AIV+20 mL·kg^-1苦参碱）和低浓度治疗组（0.1 mL 4×10⁵PFU/mLH9N2 AIV+10 mL·kg^-1苦参碱），每组12只，含病毒鸡胚尿囊液滴鼻构建小鼠病毒性肺炎模型，灌服或饮水给药治疗连续5 d，试验共进行7 d，观察不同组小鼠的体重变化。在第1、3、5、7天分别取3只小鼠无菌采血并处死，取小鼠肺组织进行病理组织学观察，RT-PCR检测小鼠肺组织中H9N2 NA、NLRP3 NLR基因表达情况，Western Blot检测苦参碱治疗后H9N2感染小鼠肺组织NLRP3炎性体信号通路相关蛋白表达量的变化，小鼠血清用ELISA法测定细胞因子TNF-α、IL-1β和IL-10表达量的变化。【结果】与病毒组相比，苦参碱高浓度治疗组病理组织学观察中H9N2 AIV感染小鼠肺部水肿的区域明显减少，红细胞渗出减少，炎性细胞数量减少，效果接近金刚烷胺组。7 d时苦参碱高浓度治疗组小鼠肺泡壁完好，肺泡之间分界清楚，肺组织内炎性细胞、浆细胞数量大量减少，与空白组无异;苦参碱中浓度治疗组肺组织少量出血，肺泡内无渗出液，肺泡间隔完好;苦参碱低浓度治疗组可见肺泡内红细胞渗出，大量浆细胞募集，肺泡之间出现融合现象。经过苦参碱和金刚烷胺治疗的各组小鼠肺组织中H9N2病毒基因表达量在3、5和7 d极显著降低（P<0.01）。经治疗3、5 d时，苦参碱高浓度治疗组和金刚烷胺组的NLRP3基因和蛋白表达量、TNF-α、IL-1β蛋白表达量极显著降低（P<0.01）;7 d时，苦参碱高、中、低治疗组小鼠肺组织中NLRP3基因表达量极显著降低（P<0.01）;5 d时苦参碱低浓度治疗组NLRP3蛋白、Caspase-1蛋白和中浓度组Caspase-1蛋白表达量显著降低（P<0.05）;3 d、5 d时苦参碱中、低浓度治疗组TNF-α和IL-1β蛋白表达量极显著降低（P<0.01），苦参碱中浓度治疗组IL-10表达量极显著降低。【结论】苦参碱可在体内抑制H9N2 AIV的表达，通过下调NLRP3炎性体信号通路相关蛋白，下调TNF-α、IL-1β和IL-10的表达，减轻炎症反应，有良好的抗病毒、抗炎作用。     

畜禽肌纤维发育规律及相关基因研究进展

肌肉组织分为骨骼肌、心肌和平滑肌3种类型。其中骨骼肌是畜禽最大的器官，约占畜禽身体质量的40%，它由大小、形状及肌肉收缩蛋白含量不同的肌纤维构成，对维持身体姿势、呼吸和体温调节是必不可少的。在肌纤维发育的各阶段，复杂的外在和内在机制共同调控着肌肉的发生，相关的信号机制在这当中起着决定性作用。畜禽的骨骼肌是主要的肉产品来源，而肉质性状的改善也是每个畜禽场的重要目标，因此对肌纤维的发生及相关机制的全面了解是很有必要的。本文通过整合1987—2022年国内外肌纤维研究相关文献，对肌纤维的发生、类型及调控机制进行了综述，重点介绍了与畜禽肌纤维发育规律相关的基因及信号通路，并对目前畜禽肌纤维调控机制研究存在的问题提出了建议和未来研究的方向进行了展望。