Division of Women's Health, Department of Medicine, Brigham and Women's Hospital, BC-3 1620 Tremont Street, Boston, MA 02120, USA; Department of Psychiatry, Brigham and Women's Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA.
Division of Women's Health, Department of Medicine, Brigham and Women's Hospital, BC-3 1620 Tremont Street, Boston, MA 02120, USA.
J Affect Disord. 2019 Jan 1;242:29-38. doi: 10.1016/j.jad.2018.07.088. Epub 2018 Aug 18.
The neurobiological mechanisms involved in divergent appetitive phenotypes in major depressive disorder (MDD) are not well understood, although recent data suggest disruption in mesolimbic reward circuitry. Ghrelin, an orexigenic hormone, has been shown to modulate the reward circuitry. We aimed to investigate the relationship between acylated ghrelin levels and the neural response to food stimuli in individuals with hyperphagic and hypophagic MDD in remission.
Women with hyperphagic MDD (n = 10), hypophagic MDD (n = 18), and healthy controls (HC; n = 18) underwent fMRI scanning during which they viewed images of food. The fMRI session was followed by a standardized meal, appetite ratings, and serial blood draws.
In individuals with hyperphagic MDD, greater change in acylated ghrelin in response to a meal was associated with increased BOLD response to high-calorie food in the bilateral ventral tegmental area and left hypothalamus. In contrast, negative associations were observed between acylated ghrelin AUC and BOLD activity in the right hypothalamus in the hypophagic MDD group.
Unbalanced group sizes with a relatively small sample in the hyperphagic MDD group.
In the absence of differences in absolute ghrelin levels between the hyperphagic MDD and HC groups, results in hyperphagic MDD might suggest a ghrelinergic signaling mechanism for increased appetite during an MDD episode in this group. Our findings shed light on interactions between appetite hormones and mesolimbic circuitry which could contribute to development of therapeutic targets for opposing appetite phenotypes in depression.
尽管最近的数据表明边缘奖赏回路中断，但人们对重性抑郁障碍（MDD）中不同的食欲表型相关的神经生物学机制仍了解甚少。促生长素激素，一种食欲刺激激素，已被证明可以调节奖赏回路。我们旨在研究缓解期暴食和少食 MDD 个体酰化 ghrelin 水平与对食物刺激的神经反应之间的关系。
10 名暴食 MDD 患者（n = 10）、18 名少食 MDD 患者（n = 18）和 18 名健康对照（HC；n = 18）接受 fMRI 扫描，在此期间他们观看食物图片。在 fMRI 检查后进行标准化餐食、食欲评估和连续采血。
在暴食 MDD 个体中，餐后酰化 ghrelin 变化与双侧腹侧被盖区和左侧下丘脑对高热量食物的 BOLD 反应增加有关。相比之下，在少食 MDD 组中，acylated ghrelin AUC 与右侧下丘脑的 BOLD 活动呈负相关。
暴食 MDD 组的组间大小不平衡，且样本量相对较小。
在暴食 MDD 组和 HC 组之间绝对 ghrelin 水平没有差异的情况下，暴食 MDD 组的结果可能表明在该组的 MDD 发作期间，食欲增加与 ghrelin 能信号机制有关。我们的研究结果揭示了食欲激素和边缘奖赏回路之间的相互作用，这可能有助于为抑郁症中的食欲表型提供治疗靶点。
