Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5T 3H7, Canada.
Cell Metab. 2013 Jan 8;17(1):61-72. doi: 10.1016/j.cmet.2012.12.010.
Vascular endothelial growth factor A (VEGF) is highly expressed in adipose tissue. Its role, however, has not been fully elucidated. Here, we reveal the metabolic role of adipose-VEGF by studying mice with deletion (VEGF(AdΔ)) or doxycycline-inducible overexpression of a VEGF transgene (VEGF(AdTg)) in the adipose tissue. VEGF(AdΔ) mice have reduced adipose vascular density and show adipose hypoxia, apoptosis, inflammation, and metabolic defects on a high-fat diet. In contrast, induction of VEGF expression in VEGF(AdTg) mice leads to increased adipose vasculature and reduced hypoxia. The latter changes are sufficient to counteract an established compromising effect of high-fat diet on the metabolism, indicating that metabolic misbalance is reversible by adipose vessel density increase. Our data clearly show the essential role of VEGF signaling for adequate adipose function. Besides revealing insights into the molecular mechanisms of obesity-related metabolic diseases, this study points to the therapeutic potential of increased adipose angiogenesis.
血管内皮生长因子 A(VEGF)在脂肪组织中高度表达。然而,其作用尚未完全阐明。在这里,我们通过研究脂肪组织中 VEGF 缺失(VEGF(AdΔ))或强力霉素诱导的 VEGF 转基因过表达(VEGF(AdTg))的小鼠,揭示了脂肪-VEGF 的代谢作用。VEGF(AdΔ)小鼠的脂肪血管密度降低,并表现出脂肪缺氧、细胞凋亡、炎症和代谢缺陷,在高脂肪饮食下尤为明显。相比之下,在 VEGF(AdTg)小鼠中诱导 VEGF 表达会导致脂肪血管增加和缺氧减少。后者的变化足以抵消高脂肪饮食对代谢的已建立的不利影响,表明代谢失衡可以通过增加脂肪血管密度来逆转。我们的数据清楚地表明 VEGF 信号对适当的脂肪功能至关重要。除了揭示肥胖相关代谢性疾病的分子机制的见解外,这项研究还指出了增加脂肪血管生成的治疗潜力。