目的研究热量限制在卵巢功能保护中的作用,并初步探讨其机制。方法取8周健康雌性C57BL/6小鼠30只,随机分为自由饮食组和热量限制组,建立热量限制小鼠模型。比较两组小鼠卵巢功能(HE染色进行卵泡计数),实时荧光定量PCR技术检测小鼠卵巢组织抗苗勒管激素(AMH)mRNA的表达水平及抗氧化应激相关指标[包括基因sirtuin(SIRT)3、缺氧诱导因子10L(HIF-1α)和过氧化氢酶(CAT)mRNA]的表达水平。采用ELISA方法测定小鼠血清雌二醇、孕酮的浓度,合笼后评价小鼠的产仔存活率。结果总卵泡数热量限制组为546个、自由饮食组286个,自由饮食组小鼠卵巢中的始基卵泡比例为29.4%(84/286)、闭锁卵泡比例为16.8%(48/286),热量限制组小鼠卵巢中的始基卵泡比例为38.6%(211/546)、闭锁卵泡比例为5.3%(29/546),两组分别比较,差异均有统计学意义(P〈0.05)。热量限制组小鼠AMHmRNA表达水平为3.37,较自由饮食组1.00比较,差异有统计学意义(P〈0.05)。热量限制组小鼠SIRT3mRNA表达水平为1.39,CATmRNA表达水平为1.55,HIF-1dmRNA表达水平为0.31,分别与自由饮食组(均为1.00)比较,差异均有统计学意义(P〈0.05)。热量限制组小鼠卵巢组织中血清雌二醇浓度为(5.3-4-1.6)pmol/L、孕酮浓度(0.4±0.3)nmol/L,自由饮食组分别为(3.6±1.6)pmol/L、(1.4±0.8)nmoL/L,两组分别比较,差异有统计学意义(P〈0.05)。热量限制组产仔存活率[44%(27/62)]高于自由饮食组[39%(21/54)],两组比较,差异有统计学意义(P〈0.05)。结论热量限制能够延缓卵巢衰老的进程,通过抑制卵泡募集及排卵,从而减少卵泡消耗,有效保护卵巢储备及生殖内分泌功能;同时热量限制能够减少卵泡闭锁的发生,其具体作用可能与抗氧
Objective To study the protective effects on ovarian function by caloric restriction (CR) and its mechanism. Methods Thirty female C57BL/6 mice of 8 weeks old were randomly divided into two groups, including ad libitum (AL) group and caloric restriction (CR) group. The general situation and ovarian function of those mice were compared and evaluated. Ovarian follicles were counted by hematoxylin-eosin staining. Anti-Miillerian Hormone(AMH) mRNA expression of the ovary were detected by using real-time PCR. The concentrations of serum estradiol, progesterone of the mice were measured by ELISA. And the fertility of mice by mating trials were evaluated, SIRT3, Hypoxia inducible factor lα (HIF-lα) and catalase (CAT) mRNA expression of the mice ovaries were detected by Real-Time PCR. Results The total follicles were 546 in CR mice and 286 in AL mice. The proportion of primordial follicles were 38.6% (211/546)in ovaries of CR mice and 29. 4% (84/286)in ovaries of AL mice, which reached statistical difference. The proportion of atretic follicles 5.3% ( 29/546 ) in ovaries of CR mice, compared with 16. 8% (48/286) in AL mice, was significantly decreased ( P 〈 0. 05 ). The AMH mRNA expression in CR mice ovaries was 3.37 times of that of AL mice ( P 〈 0. 05 ). The serum concentration of estradiol in CR mice was up to (5.3 ±1.6) pmol/L, which was much higher than (3.6 ± 1.6) pmol/L in AL mice. While, the progesterone concentration of (0.4 ±0. 3 ) nmoL/L in CR mice was lower than ( 1.4±0. 8) nmol/L in AL mice ( P 〈 0. 05 ) . Fertility and survival of offsprings were both improved in CR mice. The expression level of SIRT3 mRNA in CR mice ovary was 1.39 times, CAT was 1.55 times and HIF-1α was 0. 31 times of those in AL mice ( P 〈 0. 05 ). Conclusions Caloric restriction can delay the ovary aging process through reduce follicle depletion by suppressing follicle recruitment and ovulation. The function of ovarian reserve and reproductive endocri