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1.
This study was conducted to evaluate the influence of back‐fat thickness (BF), at mating of sows, on the maternal and newborn circulating lipids, expression of placental fatty acids (FA) transporters and lipid accumulation in placenta. Full‐term placentas were obtained by vaginal delivery from BFI (9–14 mm; n = 37), BFII (15–19 mm; n = 43) and BFIII (20–27 mm; n = 38) sows according to BF at mating, and frozen placental sections were analysed for fat accumulation. Blood samples were collected from the sows of day 105 pregnancy and from cord blood at delivery. mRNA and protein expression levels were evaluated with real‐time RT‐PCR and Western blotting. Our results demonstrated that BFII females had significantly increased litter weight and placental efficiency, decreased maternal triglyceride (TG) and non‐esterified fatty acids (NEFA) levels, decreased maternal IL‐6, TNFα and leptin levels compared to BFIII females (< .05). BFIII sows were associated with significantly decreased newborn TG levels, increased newborn glucose, IL‐6 and TNFα levels compared to BFI or BFII sows (< .05). BFI and BFII females had significantly decreased placental TG, NEFA and cholesterol (CHOL) contents compared to BFIII females (< .05). Moreover, decreased CD36, FATP1, FABP4, and FABP1 mRNA and protein and FATP4 protein expression, and increased LPL activity were also observed in BFIII group compared with BFII group (< .05). PPARγ mRNA and protein and lipogenic genes such as SREBP‐1c, ACSL1, ACCα, FAS and SCD mRNA expression were downregulated or upregulated, respectively, in the placentas of BFIII sows compared to BFI or BFII sows (< .05). Overall, this study demonstrated that there is no advantage, in terms of litter live size, litter weight and placental FA transport and metabolism, in performing the mating of sows with BF>19 mm.  相似文献   
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随着分子遗传学的发展,已经鉴定出了影响剩余采食量(RFI)的大量数量性状位点和候选基因。有丝分裂原活化蛋白3激酶5(MAP3K5),也称凋亡信号调节激酶1(ASK1),属于MAPK超家族基因之一。目前,已有细胞外信号调节蛋白激酶(ERK)、c-Jun N-末端激酶(JNK)和p38丝裂原激活蛋白激酶(p38-MAPK)这3个MAPK家族成员在哺乳动物细胞中被克隆和鉴定,其主要作用机制是介导3条MAPKs信号通路,从而影响家畜的生长、体型及产奶性状等。课题组在前期对RFI的研究中筛选出与牛剩余采食量相关的MAP3K5基因,但其功能作用尚不明确,笔者在此基础上回顾了该基因的结构、生物学功能,概述了该基因在主要畜禽采食量变异及人类肥胖表型中的功能及作用,并从遗传学的角度重点分析了MAP3K5基因在畜禽RFI表型调控中的可能机制。通过对MAP3K5基因在畜禽RFI表型调控中的研究进展进行综述,期望为后期深入开展MAP3K5基因在畜禽采食量性状调控中的分子机制研究提供思路;对于其他可能通过MAP3K5基因影响畜禽表型的因素(如肠道菌群)有待进一步探讨。  相似文献   
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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   
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全球性肥胖流行问题愈发严峻,而脂肪组织本身可能是解决这个问题的关键。人和哺乳动物体内存在两种脂肪组织,发挥着截然相反的作用。与白色脂肪组织存储机体过剩的能量不同,棕色脂肪组织中存在独特的解偶联蛋白,能将脂肪酸氧化磷酸化,释放热能,增加能量消耗。因此,通过激活棕色脂肪组织产热,加速体内储存的脂质氧化磷酸化,成为了一种新的预防和治疗肥胖的手段。论文阐述影响棕色脂肪产热活性的因素以及相关机制,旨在为肥胖的治疗提供新的思路和方向。  相似文献   
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魔芋甘露聚糖对营养性肥胖大鼠的作用   总被引:2,自引:0,他引:2  
试验结果表明魔芋甘露聚糖(0.17~1.5g/kg)可降低营养性肥胖大鼠的体重,减少脂肪堆积,脂肪细胞的数量和大小,可使肥胖大鼠的血清甘油三酯、高密度脂蛋白、血糖有所降低,提示魔芋甘露聚糖减肥作用的机制之一是使其小肠绒毛膜的形态正常化,使亢进的吸收功能恢复正常。  相似文献   
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ObjectiveTo determine if body condition score (BCS) influences the sedative effect of intramuscular (IM) premedication or the dose of intravenous (IV) propofol required to achieve endotracheal intubation in dogs.Study designProspective clinical study.AnimalsForty–six client–owned dogs undergoing general anaesthesia.MethodsDogs were allocated to groups according to their BCS (BCS, 1 [emaciated] to 9 [obese]): Normal–weight Group (NG, n = 25) if BCS 4–5 or Over–weight Group (OG, n = 21) if BCS over 6. Dogs were scored for sedation prior to IM injection of medetomidine (5 μg kg?1) and butorphanol (0.2 mg kg?1) and twenty minutes later anaesthesia was induced by a slow infusion of propofol at 1.5 mg kg?1 minute?1 until endotracheal intubation could be achieved. The total dose of propofol administered was recorded. Data were tested for normality then analyzed using Student t–tests, Mann–Whitney U tests, chi–square tests or linear regression as appropriate.ResultsMean ( ± SD) propofol requirement in NG was 2.24 ± 0.53 mg kg?1 and in OG was 1.83 ± 0.36 mg kg?1. The difference between the groups was statistically significant (p = 0.005). The degree of sedation was not different between the groups (p = 0.7). Post–induction apnoea occurred in 11 of 25 animals in the NG and three of 21 in OG (p = 0.052).ConclusionsOverweight dogs required a lower IV propofol dose per kg of total body mass to allow tracheal intubation than did normal body condition score animals suggesting that IV anaesthetic doses should be calculated according to lean body mass. The lower dose per kg of total body mass may have resulted in less post–induction apnoea in overweight/obese dogs. The effect of IM premedication was not significantly affected by the BCS.Clinical relevanceInduction of general anaesthesia with propofol in overweight dogs may be expected at lower doses than normal–weight animals.  相似文献   
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The recent research achievements about the mechanisms of beneficial health effects of tea polyphenols and the epidemiological investigation on anti-cancer,anti-cardiovascular diseases,and anti-obesity through tea consumption were reviewed.It is proved that reactive oxygen species is the main reason to induce cell mutation,DNA damage,obesity,high blood pressure and many kinds of cancers.Tea catechins and theaflavins have excellent bioactivity on scavenging ROS due to their characteristic structure feature of phenolic hydroxyl group,which means drinking tea could prevent diseases.Epidemidogical investigations also showed that tea consumption could reduce the risk of lung cancer,gastric cancer,bladder cancer,and so on.However,the frequency of tea drinking or tea consumption amounts significantly affected the prevention efficiency.The epidemiologic investigations also find that drink green tea,especial black tea is useful to modify the cardiovascular diseases.In vivo and vitro tests showed that tea supplement could moderate the metabolism of blood lipid and prevent obesity.These indicated that tea and tea extracts might reduce the risk of many diseases.  相似文献   
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为考察温阳为主中药复方对肥胖大鼠糖代谢的影响,采用高脂饲料喂养12周建立肥胖大鼠模型,将造模成功的 SD 肥胖大鼠随机分成3组,分别为模型组、二甲双胍组、温阳复方组,并设正常对照组。连续灌胃8周,在给药第4、8周测其空腹血糖,给药 8周后测口服糖耐量与肌糖原、肝糖原、糖化血红蛋白含量。结果显示,给药 8周后,温阳复方组空腹血糖和糖化血红蛋白含量降低,肌糖原、肝糖原含量升高。结果表明,温阳复方能够明显纠正肥胖大鼠糖代谢紊乱,有效预防和延缓早期糖尿病的发生。  相似文献   
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目的:探讨大强度间歇游泳运动对青年肥胖女性减肥的效果。方法:20名自愿参加青年肥胖女性随机分为对照组和实验组各10名,实验组进行12周4次/周大强度间歇游泳运动,运动方案为以85%VO2max强度完成200m游、再以55%VO2max强度完成100m游、间歇休息3min为一组,重复6组;在运动计划实施前和12周结束时采用ZEUS9.9身体成分分析仪测定受试者身体成分。结果:与对照组或运动前比较,实验组青年肥胖女性的体重、BMI、腰围、臀围、WHR、体脂%、身体脂肪、内脏脂肪和皮下脂肪均出现极显著性或显著性减少(P<0.01,P<0.05),而肌肉量和蛋白质量则出现显著性增加 (p<0.05)。结论:大强度间歇游泳运动对青年肥胖女性有明显的减肥效果。  相似文献   
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