OBJECTIVE To investigate the effect of microRNA-32 on cold-induced thermogenesis and brown adipocyte energy metabolism.METHODS To apply the cold-induced thermogenesis model in mice,8-10 week old male C57Bl6 mice were ...OBJECTIVE To investigate the effect of microRNA-32 on cold-induced thermogenesis and brown adipocyte energy metabolism.METHODS To apply the cold-induced thermogenesis model in mice,8-10 week old male C57Bl6 mice were placed within a 6℃fridge for 7d.Control microRNA inhibitor or miR-32 inhibitor(10mg·kg-1)was administered via intraperitoneal injection 16 hbefore the mice were placed in the fridge.Daily core body temperatures were taken using a rectal temperature probe.Mice were euthanized after 7dand brown adipose tissue(BAT),inguinal and epididymal white adipose tissue(WAT),skeletal muscle and liver tissue analysed for changes in morphology and gene expression.RESULTS miR-32 inhibition in vivoinhibits the emergence of beige cells,which function like BAT cells,within WAT.In silico prediction and gene ontology analysis identified Tob1 as a likely target gene of miR-32.miR-32 inhibition led to increased expression of Tob1 whilst mutation of target sequence abolished this effect.Expression of brown adipose markers such as Ucp1,Pgc1α,Pparαand Prdm16 were significantly reduced in inguinal white adipose tissue(P<0.05).There was also a significant decrease in serumfgf21 levels due to the inhibition of Fgf21 expression in BAT(P<0.05).p38/MAPK signalling in brown adipose tissue was also significantly inhibited within brown adipose tissue leading to decreased fgf21 expression and secretion.CONCLUSION Our study shows that miR-32 plays a crucial role in stimulating beige cell emergence by activating p38/MAPK signalling during cold thermogenesis.miR-32 may prove effective as a treatment for obesity by activating cold-induced thermogenesis leading to increased energy metabolism.展开更多
安县大光包滑坡是汶川地震触发的最大规模滑坡,滑坡南侧暴露长约1.8 km顺层滑带,其岩体高度碎裂化,引起广泛关注。为准确评价滑带碎裂岩体的强度参数,笔者在前人研究的基础上开展了细致的野外调查工作,采用法国Phicometre岩土两用原位...安县大光包滑坡是汶川地震触发的最大规模滑坡,滑坡南侧暴露长约1.8 km顺层滑带,其岩体高度碎裂化,引起广泛关注。为准确评价滑带碎裂岩体的强度参数,笔者在前人研究的基础上开展了细致的野外调查工作,采用法国Phicometre岩土两用原位钻孔剪切试验仪对大光包滑坡滑带碎裂岩体进行了原位剪切试验。将试验结果与Hoek–Brown岩体强度准则估值和基于工程地质类比法的力学参数建议值进行了对比分析。基于以上研究,提出了大光包滑坡南侧顺层滑带碎裂岩体力学参数建议值:内聚力为245~480 k Pa,内摩擦角为25.0°~26.5°。展开更多
2008年联合国环境规划署（UNEP）发布了研究报告《大气棕色云——亚洲区域评价报告》（Atmospheric Brown Clouds—Regional Assessment Report with Focus on Asia）,重点介绍了大气棕色云的基本概念、辐射强迫和气候效应,对有关亚洲...2008年联合国环境规划署（UNEP）发布了研究报告《大气棕色云——亚洲区域评价报告》（Atmospheric Brown Clouds—Regional Assessment Report with Focus on Asia）,重点介绍了大气棕色云的基本概念、辐射强迫和气候效应,对有关亚洲大气棕色云和区域气候变化的最新研究进展进行了综述。展开更多
基金The project supported by Singapore Institute for Clinical Sciences(SICS)A*STAR Singapore and BMRC Young Investigator Grant
文摘OBJECTIVE To investigate the effect of microRNA-32 on cold-induced thermogenesis and brown adipocyte energy metabolism.METHODS To apply the cold-induced thermogenesis model in mice,8-10 week old male C57Bl6 mice were placed within a 6℃fridge for 7d.Control microRNA inhibitor or miR-32 inhibitor(10mg·kg-1)was administered via intraperitoneal injection 16 hbefore the mice were placed in the fridge.Daily core body temperatures were taken using a rectal temperature probe.Mice were euthanized after 7dand brown adipose tissue(BAT),inguinal and epididymal white adipose tissue(WAT),skeletal muscle and liver tissue analysed for changes in morphology and gene expression.RESULTS miR-32 inhibition in vivoinhibits the emergence of beige cells,which function like BAT cells,within WAT.In silico prediction and gene ontology analysis identified Tob1 as a likely target gene of miR-32.miR-32 inhibition led to increased expression of Tob1 whilst mutation of target sequence abolished this effect.Expression of brown adipose markers such as Ucp1,Pgc1α,Pparαand Prdm16 were significantly reduced in inguinal white adipose tissue(P<0.05).There was also a significant decrease in serumfgf21 levels due to the inhibition of Fgf21 expression in BAT(P<0.05).p38/MAPK signalling in brown adipose tissue was also significantly inhibited within brown adipose tissue leading to decreased fgf21 expression and secretion.CONCLUSION Our study shows that miR-32 plays a crucial role in stimulating beige cell emergence by activating p38/MAPK signalling during cold thermogenesis.miR-32 may prove effective as a treatment for obesity by activating cold-induced thermogenesis leading to increased energy metabolism.
文摘安县大光包滑坡是汶川地震触发的最大规模滑坡,滑坡南侧暴露长约1.8 km顺层滑带,其岩体高度碎裂化,引起广泛关注。为准确评价滑带碎裂岩体的强度参数,笔者在前人研究的基础上开展了细致的野外调查工作,采用法国Phicometre岩土两用原位钻孔剪切试验仪对大光包滑坡滑带碎裂岩体进行了原位剪切试验。将试验结果与Hoek–Brown岩体强度准则估值和基于工程地质类比法的力学参数建议值进行了对比分析。基于以上研究,提出了大光包滑坡南侧顺层滑带碎裂岩体力学参数建议值:内聚力为245~480 k Pa,内摩擦角为25.0°~26.5°。
文摘2008年联合国环境规划署（UNEP）发布了研究报告《大气棕色云——亚洲区域评价报告》（Atmospheric Brown Clouds—Regional Assessment Report with Focus on Asia）,重点介绍了大气棕色云的基本概念、辐射强迫和气候效应,对有关亚洲大气棕色云和区域气候变化的最新研究进展进行了综述。
