Abstract：
Lipids are compounds involved in many biologic functions including cell structure, metabolism, energy storage and are involved in signaling. A prominent lipid in these functions is cholesterol. Cholesterol also plays a part in the signaling of melanocytes, which contain melanosomes. The maturation of these melanosomes happens during melanocyte growth. The deficit of melanogenesis or melanosome maturation is associated with ocular albinism in the eye. Aberrations of melanosome maturation are also associated with pigment dispersion syndrome. Albinism and pigment dispersion manifestations are systemic. Both melanogenesis and melanocyte maturation are affected by cholesterol metabolism. Cholesterol signaling is a part of many pathways in the body, and evaluating these signals can have implications in systemic disease processes of melanogenesis and melanosome maturation, like ocular albinism and pigment dispersion. Cholesterol is carried by lipoprotein particles. Low-density lipoprotein (LDL) is usually the transport vehicle for cholesterol to reach tissues and organelles. The LDL uptake on cells often sends out a cascade of internal signaling within the cells. We describe here LDL signaling related to lipase activity changes using enzymatic methods with a kit. We describe analyses of cholesterol esters and free cholesterol with liquid chromatography and gas chromatography with or in tandem with mass spectrometry (GC-MS and LC-MS/MS). These analyses will provide insight into melanosome maturation and melanogenesis. The methods described here are applicable to all melanocytes within the body of a model mammalian organism.
摘要：
脂质是涉及许多生物学功能的化合物，包括细胞结构，新陈代谢，能量存储，并参与信令。这些功能中突出的脂质是胆固醇。胆固醇也在黑素细胞的信号中发挥作用，含有黑色素体。这些黑色素体的成熟发生在黑素细胞生长期间。黑色素生成或黑素体成熟的缺陷与眼睛中的眼白化病有关。黑素体成熟畸变也与色素分散综合征有关。白化病和色素分散表现是系统性的。黑素生成和黑素细胞成熟都受胆固醇代谢的影响。胆固醇信号是体内许多途径的一部分，评估这些信号可能对黑素生成和黑素成熟的全身性疾病过程有影响，像眼白化病和色素分散。胆固醇由脂蛋白颗粒携带。低密度脂蛋白（LDL）通常是胆固醇到达组织和细胞器的运输载体。细胞上的LDL摄取通常在细胞内发出级联的内部信号。我们在这里描述了使用试剂盒的酶促方法与脂肪酶活性变化相关的LDL信号传导。我们描述了使用液相色谱法和气相色谱法以及质谱联用（GC-MS和LC-MS/MS）对胆固醇酯和游离胆固醇的分析。这些分析将提供对黑素体成熟和黑素生成的深入了解。本文描述的方法适用于模型哺乳动物生物体体内的所有黑素细胞。
