肥胖世界ObesityWorld . 《肥胖世界》Obesity World - 同步传真肥胖及代谢国际新学术进展，为医学减重临床、教研人员搭建一座与国际接轨的桥梁，「每医健」旗下内容平台。 以下文章来源于肥胖世界ObesityWorld ，作者欢迎订阅 研究人员通过敲除小鼠交感神经中的NPY后发现，小鼠的棕色脂肪会变"白"，产热能力明显下降，能量消耗也随之减少。即便小鼠只吃普通鼠 粮，也会变得特别容易发胖。 有时候我们在影视剧中会看到那种极其复杂的人物角色，他们既有黑暗的一面，也会做出善良的举动，坏事和好事都实打实地做过，让观众对 他们又爱又恨、充满矛盾。 其实，人体内的细胞和各种信号分子有时也像这样"双面"，在不同的时间和部位会展现出完全不同的功能，这种变化常常让科学家们感到困 惑。 今天，《自然》杂志发表了牛津大学科学家团队的一项新成果：他们发现，原本被认为在大脑中负责"刺激食欲"的神经肽Y（NPY），在身体 外围的脂肪组织交感神经里，竟然有助于维持棕色脂肪的产热能力。 这表明，NPY对体重的调控远比想象中复杂，并不仅仅通过影响食欲来发挥作用。 一边让我们多吃，一边又帮我们消耗热量，NPY的"分裂"属性 ...

Core Insights - The article discusses the dual role of Neuropeptide Y (NPY) in regulating appetite and energy expenditure, revealing its complex functions in both the brain and peripheral fat tissues [7][12][16]. Group 1: NPY's Role in Appetite Regulation - NPY is known to stimulate appetite in the brain, but its absence does not significantly affect food intake in mice [11]. - Mutations in the NPY gene are associated with higher Body Mass Index (BMI) in humans, indicating a more complex relationship between NPY and weight regulation beyond just appetite stimulation [11][17]. Group 2: NPY's Role in Energy Expenditure - In peripheral fat tissues, NPY helps maintain the thermogenic capacity of brown adipose tissue (BAT) and promotes energy expenditure [7][12]. - Research shows that when NPY is knocked out in the sympathetic nerves of mice, their brown fat turns "white," leading to reduced thermogenic ability and increased susceptibility to weight gain, even without changes in food intake or activity levels [14][16]. Group 3: Mechanisms of NPY Action - Approximately 40% of sympathetic neurons in white adipose tissue express NPY, indicating its significant presence in fat tissue regulation [12][14]. - NPY promotes the proliferation of perivascular cells, which can differentiate into thermogenic fat cells, thus playing a crucial role in fat tissue regulation [14][16].