Functional Analysis of Lysosomes During Mouse Preimplantation Embryo Development

Lysosomes are acidic and highly dynamic organelles that are essential for macromolecule degradation and many other cellular functions. However, little is known about lysosomal function during early embryogenesis. Here, we found that the number of lysosomes increased after fertilization. Lysosomes were abundant during mouse preimplantation development until the morula stage, but their numbers decreased slightly in blastocysts. Consistently, the protein expression level of mature cathepsins B and D was high from the one-cell to morula stages but low in the blastocyst stage. One-cell embryos injected with siRNAs targeted to both lysosome-associated membrane protein 1 and 2 (LAMP1 and LAMP2) were developmentally arrested at the two-cell stage. Pharmacological inhibition of lysosomes also caused developmental retardation, resulting in accumulation of lipofuscin. Our findings highlight the functional changes in lysosomes in mouse preimplantation embryos.     

还少丹对老年小鼠脂褐素含量和 DNA分子结构稳定性的影响

〔摘要〕目的研究还少月一对老龄小鼠脂褐素含量和DNA分子结构稳定性的影响、方法将36只昆明种老年 小鼠(20月龄),按体质量随机分为3组,另设12只2月龄同种小鼠作为青年对照组,共4组:①老年对照组;②老 年还少月一组;③老年维生素E(VE)组;④青年对照组〔连续喂养10周后,采用荧光分光光度法测定脑组织的脂褐素 水平和肝组织DNA双链解旋剩余率;用紫外分光光度法测定肝组织DNA碱变性增色效应、结果青年对照组、老 年还少月一组、老年VE组的脂褐素含量明显低于老年对照组,差异有统计学意义(P<0.05;与老年对照组比较,青年 对照组和老年还少月一组的DNA碱变性增色效应明显降低,而DNA双链解旋剩余率显著增高,差异均具有统计学 意义(P<0.05,而老年VE组的差异无统计学意义(P>0.05、结论还少月一能有效降低脂褐素的含量,保护DNA结 构的稳定性,达到延缓衰老的目的、     

刺莓果在抗衰老实验中几项生化指标的研究

本文测定了刺莓果对小鼠抗衰老实验中的几项生化指标。其结果表明：刺莓果能够提高小鼠血中ＳＯＤ活性及皮肤中羟脯氨酸的含量；降低血中ＬＰＯ和心肌中脂褐素含量；并使小鼠脑及肝中ＭＡＯ—Ｂ活性下降。说明刺莓果具有一定抗衰老作用，为其开发和利用提供依据。     

Lipofuscin-like pigments in endocardial cells enveloping the heart muscle trabeculae in platyfish (Poeciliidae: Teleostei)

Large amounts of lipofuscin-like pigments were demonstrated by means of the Schmorl’s technique in endocardial cells enveloping the heart muscle trabeculae in adult platyfish (Xiphophorus maculatus). Such pigment granules occurred in a low number in the corresponding cell layers in the heart of 6-mm long prenatal platies. The endocardial cells contained numerous lysosome-like bodies, bristle-coated vesicles, and tubules of agranular endoplasmic reticulum, particularly in adult specimens. The lipofuscin-rich endocardial cell layers displayed deep blue precipitations in hearts from the ferritin-injected adult platies 6 h or more post-injection, when treated with acid ferrocyanide instead of Schmorl’s solution, i.e., this cell type is able to take up foreign particles. The occurrence of much lipofuscin-like pigments in endocardial cell layers in adult platies provides evidence that these cells have performed important scavenger functions at this stage of development.