Chronic hyperadiponectinemia induced by transgenic overexpression increases plasma exosomes without significantly improving glucose and lipid metabolism

The fat-derived factor, adiponectin, is considered a salutary circulating
factor. We recently demonstrated that native adiponectin binds T-cadherin
and promotes intracellular biogenesis and secretion of the exosome.
Exosomes play important roles in various aspects of
homeostasis, including glucose and energy metabolism. However, it
remains unclear whether and how the promotion of exosome production by
adiponectin in vivo is beneficial for glucose and lipid metabolism. In the
present study, overexpression of human adiponectin in mice resulted in an
increased number of circulating exosomes, but it did not significantly
improve glucose metabolism, change body weights, or change triglyceride
clearance under a high-fat diet. Multiple small doses of streptozotocin
increased blood glucose and decreased triglyceride clearance similarly in
both wild-type and transgenic mice. Thus, these results indicated that
human adiponectin overexpression in mice increases plasma exosomes but
does not significantly influence glucose and lipid metabolism.

脂肪来源的因子脂联素（adiponectin）被认为是一种有益的循环因子。我们近期发现，天然脂联素可结合T-钙黏蛋白（T-cadherin），并促进外泌体（exosome）的细胞内生物发生与分泌。外泌体在稳态的多个方面发挥重要作用，包括葡萄糖与能量代谢。然而，脂联素在体内促进外泌体生成是否以及如何对糖脂代谢产生益处，目前仍不明确。本研究中，在小鼠体内过表达人脂联素可增加循环外泌体数量，但在高脂饮食条件下，并未显著改善葡萄糖代谢、改变体重或影响甘油三酯清除。多次小剂量链脲佐菌素（streptozotocin）处理后，野生型与转基因小鼠的血糖均升高，甘油三酯清除率均降低，且两组变化相似。因此，这些结果表明，小鼠体内过表达人脂联素可增加血浆外泌体数量，但对糖脂代谢无显著影响。