Organ Transplantation Institute, Xiamen University, Xiamen City, Fujian Province, China.
Theriogenology. 2012 Sep 1;78(4):784-92. doi: 10.1016/j.theriogenology.2012.03.026. Epub 2012 Apr 26.
Although there is considerable evidence that diabetes can adversely affect meiosis in mammalian oocytes, acetylation status of oocytes in a diabetic environment remains unclear. The objective was to determine acetylation or deacetylation patterns (based on immunostaining) of H3K9, H3K14, H4K5, H4K8, H4K12, and H4K16 sites at various stages during meiosis in murine oocytes from control and diabetic mice. According to quantitative real time polymerase chain reaction (qPCR), mean ± SEM relative expression of Gcn5 (1.70 ± 0.14 at metaphase [M]I and 1.27 ± 0.01 at MII, respectively), Ep300 (1.74 ± 0.04 at MI and 1.80 ± 0.001 at MII), and Pcaf (2.01 ± 0.03 at MI and 1.41 ± 0.18 at MII) mRNA in oocytes from diabetic mice were higher than those from controls (P < 0.05), whereas there was no difference (P > 0.05) during the germinal vesicle (GV) stage between the two groups (1.23 ± 0.04 for Gcn5, 0.82 ± 0.06 for Ep300, and 0.80 ± 0.07 for Pcaf). Conversely, relative mRNA expression concentrations of Hdac1, Hdac2, Hdac3, Sirt1 and Sirt2 during the germinal vesicle stage were lower in oocytes of diabetic mice (0.24 ± 0.03 for Hdac1, 0.11 ± 0.001 for Hdac2, 0.31 ± 0.03 for Hdac3, 0.28 ± 0.02 for Sirt1, and 0.55 ± 0.02 for Sirt2; P < 0.05). Similarly, the expression concentrations of these genes at the MI stage were lower in oocytes from diabetic mice (0.79 ± 0.12 for Hdac1, 0.72 ± 0.001 for Hdac2, 0.02 ± 0.001 for Sirt1, and 0.84 ± 0.08 for Sirt2; P < 0.05). Their expression concentrations at the MII stage were also lower in oocytes from diabetic mice (0.46 ± 0.03 for Hdac1, 0.93 ± 0.01 for Hdac2, 0.56 ± 0.01 for Hdac3, 0.01 ± 0.002 for Sirt1, and 0.84 ± 0.04 for Sirt2; P < 0.05). At the MI stage, however, there was no difference in the expression of Hdac3 between the two groups of oocytes (0.96 ± 0.03; P > 0.05). Taken together, diabetes altered the intracellular histone modification system, which may have contributed to changes in histone acetylation, and may be involved in the compromised maturation rate of oocytes in diabetic humans.
尽管有大量证据表明糖尿病会对哺乳动物卵母细胞的减数分裂产生不利影响，但糖尿病环境中卵母细胞的乙酰化状态仍不清楚。目的是确定来自对照和糖尿病小鼠的卵母细胞在减数分裂各个阶段（基于免疫染色）中 H3K9、H3K14、H4K5、H4K8、H4K12 和 H4K16 位点的乙酰化或去乙酰化模式。根据定量实时聚合酶链反应（qPCR），Gcn5（中期 I 分别为 1.70 ± 0.14 和 MII 分别为 1.27 ± 0.01）、Ep300（MI 分别为 1.74 ± 0.04 和 MII 分别为 1.80 ± 0.001）和 Pcaf（MI 分别为 2.01 ± 0.03 和 MII 分别为 1.41 ± 0.18）mRNA 在糖尿病小鼠卵母细胞中的相对表达高于对照组（P < 0.05），而两组之间在生殖泡（GV）阶段没有差异（P > 0.05）（Gcn5 为 1.23 ± 0.04，Ep300 为 0.82 ± 0.06，Pcaf 为 0.80 ± 0.07）。相反，在生殖泡阶段，糖尿病小鼠卵母细胞中 Hdac1、Hdac2、Hdac3、Sirt1 和 Sirt2 的相对 mRNA 表达浓度较低（Hdac1 为 0.24 ± 0.03，Hdac2 为 0.11 ± 0.001，Hdac3 为 0.31 ± 0.03，Sirt1 为 0.28 ± 0.02，Sirt2 为 0.55 ± 0.02；P < 0.05）。同样，在糖尿病小鼠卵母细胞中，这些基因在 MI 阶段的表达浓度也较低（Hdac1 为 0.79 ± 0.12，Hdac2 为 0.72 ± 0.001，Sirt1 为 0.02 ± 0.001，Sirt2 为 0.84 ± 0.08；P < 0.05）。在 MII 阶段，糖尿病小鼠卵母细胞中的表达浓度也较低（Hdac1 为 0.46 ± 0.03，Hdac2 为 0.93 ± 0.01，Hdac3 为 0.56 ± 0.01，Sirt1 为 0.01 ± 0.002，Sirt2 为 0.84 ± 0.04；P < 0.05）。然而，在 MI 阶段，两组卵母细胞中 Hdac3 的表达没有差异（0.96 ± 0.03；P > 0.05）。综上所述，糖尿病改变了细胞内组蛋白修饰系统，这可能导致组蛋白乙酰化的变化，并可能参与糖尿病患者卵母细胞成熟率下降。
