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11.
Yasu-Taka AZUMA Sho SUZUKI Kazuhiro NISHIYAMA Taro YAMAGUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):622
Excessive stress response causes disability in social life. There are many diseases caused by stress, such as gastrointestinal motility disorders, depression, eating disorders, and cardiovascular diseases. Transient receptor potential (TRP) channels underlie non-selective cation currents and are downstream effectors of G protein-coupled receptors. Ca2+ influx is important for smooth muscle contraction, which is responsible for gastrointestinal motility. Little is known about the possible involvement of TRP channels in the gastrointestinal motility disorders due to stress. The purpose of this study was to measure the changes in gastrointestinal motility caused by stress and to elucidate the mechanism of these changes. The stress model used the water immersion restraint stress. Gastrointestinal motility, especially the ileum, was recorded responses to electric field stimulation (EFS) by isometric transducer. EFS-induced contraction was significantly reduced in the ileum of stressed mouse. Even under the conditions treated with atropine, EFS-induced contraction was significantly reduced in the ileum of stressed mouse. In addition, carbachol-induced, neurokinin A-induced, and substance P-induced contractions were all significantly reduced in the ileum of stressed mouse. Furthermore, the expression of TRPC3 was decreased in the ileum of stressed mouse. These results suggest that the gastrointestinal motility disorders due to stress is associated with specific non-selective cation channel. 相似文献
12.
JI Dan HE Xiao-gang WANF Gang LUO Tao ZHANG Lu XU Xiao-dan XU Xiao-jun LI Fei-fei 《园艺学报》2020,36(6):969-976
AIM To investigate the role of monocyte chemoattractant protein-1 (MCP-1) and its receptor CC chemokine receptor 2 (CCR2) in ethanol-promoted breast cancer angiogenesis and the underlying mechanism. METH?ODS: A mouse model of transplanted breast tumor with moderate alcohol consumption was established. The correlations between the expression of MCP-1/CCR2 and the expression of angiogenesis markers [platelet endothelial cell adhesion molecule-1 (PECAM-1) and vascular endothelial growth factor (VEGF)] in tumor tissues were examined by immunohistochemistry. In vitro , a 3D tumor-endothelial co-culture system was established to observe tumor angiogenesis and the role of MCP-1/CCR2 signaling pathway in alcohol-mediated angiogenesis. The cell migration ability was detected to clarify whether MCP-1/CCR2 enhanced cell mobility to form new vessels. RESULTS MCP-1 and CCR2 were both highly expressed in the breast tumor tissues of tumor-bearing mice consuming alcohol, and their expression levels were consistent with the angiogenic markers PECAM-1 and VEGF (P <0.05). The interaction between mouse breast cancer E0771 cells and endothelial cells was observed to promote angiogenesis in the 3D tumor-endothelial co-culture system with or without alcohol stimulation. MCP-1 promoted this kind of tumor angiogenesis, while CCR2 antagonist effectively inhibited the tumor angiogenesis and especially blocked alcohol-induced angiogenesis. Activation of MCP-1/CCR2 signaling pathway enhanced the migration ability of endothelial cells. CONCLUSION The MCP-1/CCR2 signaling pathway plays an important role in promoting the angiogenesis of breast cancer stimulated by alcohol. The mechanism might be that MCP-1 improves the migration of endothelial cells and then promotes angiogenesis. 相似文献
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14.
ABSTRACT The immunostimulatory and disease-resistance properties of Achyranthes aspera were evaluated in rohu (Labeo rohita) challenged with Aeromonas hydrophila. Experimental diets were enriched with leaves at 0.25% (D1) and 0.5% (D2) and seeds at 0.5% (D3); the control diet (D4) was without any enrichment. Rohu (2.02 ± 0.23 g) were cultured for 75 days and then challenged with bacteria. The highest average weight was observed in the D3 diet-fed fish. The cumulative mortality rates were 70%, 60%, 40%, and 30% in the D4, D1, D2, and D3 diets fed to rohu respectively. Enriched diets significantly increased myeloperoxidase, nitric oxide synthase, and serum lysozyme levels and decreased malondialdehyde and carbonyl protein content. Expressions of lysozyme C and lysozyme G were significantly (P < .05) higher in the D3 diet-fed fish. In the kidney, IL-1β and TLR 4 were up-regulated in enriched-diet-fed fish. Supplementation of seeds and leaves at 0.5% showed a positive impact in fish. 相似文献
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16.
TIR1/AFBs基因家族是一种存在于细胞核中的生长素受体,属于F-box蛋白基因中的一个小亚族。它们通过与相关生长素相结合活化转录因子来促进基因的表达,从而进行调控,是生长素信号转导过程中的关键部分。为了深入研究生长素信号转导机制,从TIR1/AFBs基因家族的发现与结构,家族成员表达模式的差异及对植物生长发育方面的调节等方面概括介绍了TIR1/AFBs基因家族的分子调控机制,总结了TIR1/AFBs基因的功能。最后探讨了TIR1/AFBs基因的研究方向。 相似文献
17.
中黑盲蝽Adelphocoris suturalis是一种重要的农业害虫,主要为害棉花、果树和牧草等作物。昆虫保幼激素(juvenile hormone, JH)与蜕皮激素(molting hormone, 20E)是调控昆虫生殖的主要因素。本研究运用基因克隆、基因沉默(RNAi)、实时荧光定量PCR(qPCR)等技术研究蜕皮激素受体(ecdysone receptor, EcR)、超气门蛋白(ultraspiracle protein, USP)在中黑盲蝽生殖调控中的作用。结果表明,中黑盲蝽EcR基因的ORF全长1 413 bp,编码470个氨基酸。预测蛋白质分子量为53.65 kD,pI值为7.79。中黑盲蝽USP基因ORF全长1 209 bp,编码402个氨基酸。预测蛋白质分子量为44.99 kD, pI值为7.94。与对照相比,注射dsEcR、dsUSP后6~18 d的中黑盲蝽体内EcR基因、USP基因在转录水平分别被显著抑制;卵巢的挂卵量分别仅有对照组的31.5%、86.6%;单雌产卵量减少36.0%~80.4%,显著低于对照。EcR和USP基因沉默后,产卵前期与对照相比无显... 相似文献
18.
Xiao Gang Weng Quan Jiang Song Qiong Wu Ming Chao Liu Meng Ling Wang Jiu Feng Wang 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):491-500
To acquire epidemiological data on the bovine viral diarrhea virus (BVDV) and identify cattle persistently infected (PI) with this virus, 4,327 samples from Holstein dairy cows were screened over a four-year period in Beijing, China. Eighteen BVD viruses were isolated, 12 from PI cattle. Based on genetic analysis of their 5''-untranslated region (5''-UTR), the 18 isolates were assigned to subgenotype BVDV-1m, 1a, 1d, 1q, and 1b. To investigate the innate immune responses in the peripheral-blood mononuclear cells of PI cattle, the expression of Toll-like receptors (TLRs), RIG-I-like receptors, interferon-α (IFN-α), IFN-β, myxovirus (influenza virus) resistance 1 (MX1), and interferon stimulatory gene 15 (ISG15) was assessed by qPCR. When compared with healthy cattle, the expression of TLR-7, IFN-α, and IFN-β mRNA was downregulated, but the expression of MX1 and ISG-15 mRNA was upregulated in PI cattle. Immunoblotting analysis revealed that the expression of interferon regulatory factor 3 (IRF-3) and IRF-7 was lower in PI cattle than in healthy cattle. Thus, BVDV-1m and 1a are the predominant subgenotypes in the Beijing region, and the strains are highly divergent. Our findings also suggest that the TLR-7/IRF-7 signaling pathway plays a role in evasion of host restriction by BVDV. 相似文献
19.
Background
Exogenous melatonin could induce cashmere growth. However, induced growth of cashmere fleece by melatonin implants cannot be combined with the typical growth, resulting in earlier shedding followed by another cycle of cashmere growth. To address this issue, we examine the effects on the cashmere yield, fibre characteristics, and the growth and reproductive performance of cashmere goats of planned administration of melatonin.Methods
Eighteen half-sib, female goats were assigned to two treatments (n = 9) including a control and a treatment where melatonin (2 mg/kg BW) was implanted at the end of April and end of June. Cashmere growth and shedding were observed for approximately 1 year following implantation. Fibre samples were collected monthly to determine cumulative cashmere length. Initiation and cessation dates for cashmere growth as well as the rate of cashmere growth were calculated. Cashmere yield, weight gain of dam, kidding date, litter size, and birth weight were also recorded.Results
Melatonin implantation increased cashmere yield by 34.5 % (control 553.7 g vs. melatonin 745.0 g; P < 0.01), cashmere length by 21.3 % (control 95.2 mm vs. melatonin 115.4 mm; P < 0.01), and decreased fibre diameter by 4.4 % (control 14.6 μm vs. melatonin 14.0 μm; P < 0.03). In melatonin-treated goats, the average initiation date was earlier than in control goats (May 18, 2013 vs. July 2, 2013; P < 0.01) but there was a similar cessation date (March 22, 2014 vs. March 27, 2014). Consequently, the duration of cashmere growth was longer in melatonin-treated goats than in control goats (307 vs.270 days; P < 0.01). The final BW, average daily gain, kidding date, litter size, and birth weight were not influenced by melatonin implantation.Conclusions
These data indicate that melatonin implantation (2 mg/kg BW) on two occasions (late April and June) increased cashmere yield by combining the induced growth of cashmere fleece with the typical growth and decreased the fibre diameter without changing dam growth rate or reproductive performance. 相似文献20.
Masahiro MIYABE Azusa GIN Eri ONOZAWA Mana DAIMON Hana YAMADA Hitomi ODA Akihiro MORI Yutaka MOMOTA Daigo AZAKAMI Ichiro YAMAMOTO Mariko MOCHIZUKI Toshinori SAKO Katsutoshi TAMURA Katsumi ISHIOKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1201-1206
G protein-coupled receptor (GPR) 120 is an unsaturated fatty acid receptor, which is
associated with various physiological functions. It is reported that the genetic variant
of GPR120, p.Arg270His, is detected more in obese people, and this genetic variation
functionally relates to obesity in humans. Obesity is a common nutritional disorder also
in dogs, but the genetic factors have not ever been identified in dogs. In this study, we
investigated the molecular structure of canine GPR120 and searched for candidate genetic
variants which may relate to obesity in dogs. Canine GPR120 was highly homologous to those
of other species, and seven transmembrane domains and two N-glycosylation sites were
conserved. GPR120 mRNA was expressed in lung, jejunum, ileum, colon, hypothalamus,
hippocampus, spinal cord, bone marrow, dermis and white adipose tissues in dogs, as those
in mice and humans. Genetic variants of GPR120 were explored in client-owned 141 dogs,
resulting in that 5 synonymous and 4 non-synonymous variants were found. The variant
c.595C>A (p.Pro199Thr) was found in 40 dogs, and the gene frequency was significantly
higher in dogs with higher body condition scores, i.e. 0.320 in BCS4–5 dogs, 0.175 in BCS3
dogs and 0.000 in BCS2 dogs. We conclude that c.595C>A (p.Pro199Thr) is a candidate
variant relating to obesity, which may be helpful for nutritional management of dogs. 相似文献