Kather H
Klinisches Institut für Herzinfarktforschung, Medizinischen Universitätsklinik, Heidelberg.
Ther Umsch. 2000 Aug;57(8):488-92. doi: 10.1024/0040-5930.57.8.488.
Adipose tissue is not simply a storage depot. Adipocytes secrete hormones, growth factors and cytokines, such as leptin and TNF-alpha, as well as proteins that are related to the immune system and vascular functions. Through this network of endocrine, paracrine, and autocrine signals fat cells participate in the regulation of energy homeostasis, host defense and reproduction, and may also contribute to the development of pathological states, such as insulin resistance. Adipose tissue is confined to distinct depots. In Cushing's disease or following treatment of AIDS, certain adipose depots enlarge whereas others shrink, suggesting the existence of site-specific differences in fat cell function. Increases in adipocyte number occur via replication of preadipocytes, a process that is not restricted to infancy but occurs throughout life. In contrast to still widely-held beliefs, mature fat cells can be eliminated by dedifferentiation or apoptosis. PPAR-gamma, a transcription factor that is activated by fatty acids and prostaglandins, plays a central role in adipose conversion of preadipocytes and appears to participate in controlling the size of mature fat cells as well.
脂肪组织并非仅仅是一个储存库。脂肪细胞会分泌激素、生长因子和细胞因子，如瘦素和肿瘤坏死因子-α，以及与免疫系统和血管功能相关的蛋白质。通过这种内分泌、旁分泌和自分泌信号网络，脂肪细胞参与能量稳态、宿主防御和生殖的调节，还可能促成病理状态的发展，如胰岛素抵抗。脂肪组织局限于不同的储存部位。在库欣病或艾滋病治疗后，某些脂肪储存部位会增大，而其他部位则会缩小，这表明脂肪细胞功能存在部位特异性差异。脂肪细胞数量的增加是通过前脂肪细胞的复制实现的，这一过程并非仅限于婴儿期，而是贯穿一生。与仍然广泛持有的观点相反，成熟脂肪细胞可通过去分化或凋亡被清除。过氧化物酶体增殖物激活受体γ（PPAR-γ）是一种由脂肪酸和前列腺素激活的转录因子，在脂肪前体细胞的脂肪转化中起核心作用，似乎也参与控制成熟脂肪细胞的大小。
