中华实用儿科临床杂志
中華實用兒科臨床雜誌
중화실용인과림상잡지
Journal of Applied Clinical Pediatrics
2015年
19期
1461-1465
,共5页
目的：探讨生命早期过度营养对肝脏脂代谢相关酶的影响及其分子机制。方法将3日龄雄性幼鼠按随机数字表法分为2组：哺乳期正常营养组( NL组),每只母鼠哺育10只幼鼠；哺乳期营养过度组( SL组),每只母鼠哺育3只仔鼠。出生3周断奶。测量大鼠摄奶量、体质量、脂肪及肝组织质量。采用自动化生化分析仪检测血脂水平,实时荧光定量PCR法测定肝组织乙酰辅酶A羧化酶( ACC)、脂蛋白酯酶( LPL)、肝型脂肪酸结合蛋白(L-FABP)、肉碱棕榈酰转移酶(CPT1)和微粒体三酰甘油转移蛋白(MTP)、胆固醇调节元件结合蛋白-1c(SREBP-1c)、过氧化物酶体增生物激活受体α(PPARα)基因表达水平,Western blot法测定肝脏SREBP-1c、PPARα蛋白表达水平。结果出生2周, SL 组大鼠体质量( t =-5.997, P<0.001)及摄奶量( t=-3.462,P=0．002)明显高于NL组大鼠,并持续至断乳(体质量：t=-17.019,P<0.001；摄奶量：t=-2.276,P=0．031),差异均有统计学意义。出生3周,SL组大鼠脂肪组织质量[后腹膜(t=-7.643,P<0.001)；生殖周(t=5.997,P=0.001)]、肝组织质量(t=-7.812,P<0.001)、肝指数(t=-3.829,P=0.003)及血清甘油三酯水平(t=-2.703,P=0.022)高于NL大鼠,同时,SL组大鼠肝脏ACC mRNA(t=-3.751,P=0.007)、LPL mRNA(t=-2．721,P=0.017)及L-FABP mRNA(t=-2.521,P=0.026)表达水平高于NL组大鼠,差异均有统计学意义,而肝脏CPT1 mRNA(t=-1.531,P=0.155)及MTP mRNA(t=-1.741,P=0.098)表达水平差异无统计学意义。SL组大鼠肝脏SREBP-1 c mRNA(t=-2.836,P=0．016)表达增加,与ACC、LPL变化一致,而PPARαmRNA(t=-0．854,P=0.411)表达无明显变化。结论哺乳期营养过度导致大鼠断乳期肝质量增加,血脂升高。肝组织ACC、LPL、L-FABP表达上调可能是其发生发展的重要机制,而SREBP-1c可能参与脂合成代谢途径ACC表达的调控。
目的：探討生命早期過度營養對肝髒脂代謝相關酶的影響及其分子機製。方法將3日齡雄性幼鼠按隨機數字錶法分為2組：哺乳期正常營養組( NL組),每隻母鼠哺育10隻幼鼠；哺乳期營養過度組( SL組),每隻母鼠哺育3隻仔鼠。齣生3週斷奶。測量大鼠攝奶量、體質量、脂肪及肝組織質量。採用自動化生化分析儀檢測血脂水平,實時熒光定量PCR法測定肝組織乙酰輔酶A羧化酶( ACC)、脂蛋白酯酶( LPL)、肝型脂肪痠結閤蛋白(L-FABP)、肉堿棕櫚酰轉移酶(CPT1)和微粒體三酰甘油轉移蛋白(MTP)、膽固醇調節元件結閤蛋白-1c(SREBP-1c)、過氧化物酶體增生物激活受體α(PPARα)基因錶達水平,Western blot法測定肝髒SREBP-1c、PPARα蛋白錶達水平。結果齣生2週, SL 組大鼠體質量( t =-5.997, P<0.001)及攝奶量( t=-3.462,P=0．002)明顯高于NL組大鼠,併持續至斷乳(體質量：t=-17.019,P<0.001；攝奶量：t=-2.276,P=0．031),差異均有統計學意義。齣生3週,SL組大鼠脂肪組織質量[後腹膜(t=-7.643,P<0.001)；生殖週(t=5.997,P=0.001)]、肝組織質量(t=-7.812,P<0.001)、肝指數(t=-3.829,P=0.003)及血清甘油三酯水平(t=-2.703,P=0.022)高于NL大鼠,同時,SL組大鼠肝髒ACC mRNA(t=-3.751,P=0.007)、LPL mRNA(t=-2．721,P=0.017)及L-FABP mRNA(t=-2.521,P=0.026)錶達水平高于NL組大鼠,差異均有統計學意義,而肝髒CPT1 mRNA(t=-1.531,P=0.155)及MTP mRNA(t=-1.741,P=0.098)錶達水平差異無統計學意義。SL組大鼠肝髒SREBP-1 c mRNA(t=-2.836,P=0．016)錶達增加,與ACC、LPL變化一緻,而PPARαmRNA(t=-0．854,P=0.411)錶達無明顯變化。結論哺乳期營養過度導緻大鼠斷乳期肝質量增加,血脂升高。肝組織ACC、LPL、L-FABP錶達上調可能是其髮生髮展的重要機製,而SREBP-1c可能參與脂閤成代謝途徑ACC錶達的調控。
목적：탐토생명조기과도영양대간장지대사상관매적영향급기분자궤제。방법장3일령웅성유서안수궤수자표법분위2조：포유기정상영양조( NL조),매지모서포육10지유서；포유기영양과도조( SL조),매지모서포육3지자서。출생3주단내。측량대서섭내량、체질량、지방급간조직질량。채용자동화생화분석의검측혈지수평,실시형광정량PCR법측정간조직을선보매A최화매( ACC)、지단백지매( LPL)、간형지방산결합단백(L-FABP)、육감종려선전이매(CPT1)화미립체삼선감유전이단백(MTP)、담고순조절원건결합단백-1c(SREBP-1c)、과양화물매체증생물격활수체α(PPARα)기인표체수평,Western blot법측정간장SREBP-1c、PPARα단백표체수평。결과출생2주, SL 조대서체질량( t =-5.997, P<0.001)급섭내량( t=-3.462,P=0．002)명현고우NL조대서,병지속지단유(체질량：t=-17.019,P<0.001；섭내량：t=-2.276,P=0．031),차이균유통계학의의。출생3주,SL조대서지방조직질량[후복막(t=-7.643,P<0.001)；생식주(t=5.997,P=0.001)]、간조직질량(t=-7.812,P<0.001)、간지수(t=-3.829,P=0.003)급혈청감유삼지수평(t=-2.703,P=0.022)고우NL대서,동시,SL조대서간장ACC mRNA(t=-3.751,P=0.007)、LPL mRNA(t=-2．721,P=0.017)급L-FABP mRNA(t=-2.521,P=0.026)표체수평고우NL조대서,차이균유통계학의의,이간장CPT1 mRNA(t=-1.531,P=0.155)급MTP mRNA(t=-1.741,P=0.098)표체수평차이무통계학의의。SL조대서간장SREBP-1 c mRNA(t=-2.836,P=0．016)표체증가,여ACC、LPL변화일치,이PPARαmRNA(t=-0．854,P=0.411)표체무명현변화。결론포유기영양과도도치대서단유기간질량증가,혈지승고。간조직ACC、LPL、L-FABP표체상조가능시기발생발전적중요궤제,이SREBP-1c가능삼여지합성대사도경ACC표체적조공。
Objective To investigate the effect of neonatal overfeeding on the expression of lipid metabolic associated enzymes and molecular mechanisms in the livers of rats. Methods Male Sprague-Dawley rats were randomly assigned to litter sizes of three group ( small litters,SL group) or ten ( normal litters,NL group) on postnatal day 3. Body weight,milk intake,liver and fat pad (epididymal and retroperitonea) weight,and hepatic histological anal-ysis were recorded in week 2 and week 3,respectively. The levels of lipids were detected by the automatic biochemical analyzer. The mRNA expressions of acetyl-CoA carboxylase ( ACC) ,lipoprotein lipase ( LPL) ,liver-type fatty acid-binding protein (L-FABP), carnitine palmitoyltransferase 1(CPT1),microsomal triglyceride transfer protein (MTP), sterol regulatory element-binding protein-1c (SREBP-1c) and peroxisome proliferator activated receptorα(PPARα) in liver were determined by real time PCR;the protein expressions of SREBP-1c and PPARα were determined by Western lot. Results As early as week 2,the body weight of rats in SL group began to elevate (t=-5. 997,P<0. 001) and food intake (t=-3. 462,P=0. 002) compared with the rats in NL group,and persistent to weaning (body weight:t=-17. 019,P<0. 001;food intake:t=-2. 276,P=0. 031). By the time of 3 weeks old,SL rats increased visceral fat pad [ret-roperitonea (t=-7. 643,P<0. 001),epididymal (t=5. 997,P=0. 001)],liver weight (t=-7. 812,P<0. 001),hepatosomatic index (t=-3.829,P=0. 003) and serum triglyceride (TG) level (t=-2. 703,P=0. 022) compared with those of NL rats,as well as the level of hepatic ACC mRNA (t=-3. 751,P=0. 007),LPL (t=-2. 721,P=0. 017) and L-FABP mRNA (t=-2. 521,P=0. 026) . While CPT1 mRNA (t=-1. 531,P=0. 155) and MTP mRNA (t=-1. 741,P=0. 098) levels remained unchanged in both groups. Hepatic SREBP-1c mRNA expression increased in SL rats after 2 to 3 weeks (t=-2. 836,P=0. 016),paralleled with ACC and LPL mRNA expression;while the mRNA and protein expression of PPARα re-mained unchanged (t=-0. 854,P=0. 411). Conclusions Postnatal overfeeding can promote higher liver pad and dyslip-idemia at the time of weaning. The process may be regulated by up-regulated expression of ACC, LPL and L-FABP. SREBP-1c may be participated in the regulation of ACC,a rate-limiting enzyme involved in lipogenesis.
