הנכם מוזמנים להרצאת ההתקדמות של
סיגל רוזנבליט, תלמידתה של פרופ' אורן פרוי,
במסגרת הסמינר המכוני של המכון לביוכימיה, מדעי המזון והתזונה.
מועד: יום ה', 19/07/2018 בשעה 11:00 (קבלת פנים וכיבוד קל בשעה 10:45)
מרצה: סיגל רוזנבליט
נושא: השפעת סרוטונין על מקצבים יומיים ומטבוליזם ברקמות היקפיות ועל התמיינות של רקמת שומן חום
Effect of serotonin on circadian rhythm and metabolism in peripheral tissues and brown adipocyte differentiation
The circadian clock is located in the suprachiasmatic nuclei (SCN) of the anterior hypothalamus. Disrupted circadian rhythms lead to attenuated circadian feeding rhythms, hyperphagia, diabetes and obesity. Serotonin is a biogenic amine most noted for its role as a neurotransmitter. It is widely distributed in the central nervous system, and is implicated in many behavioral aspects, such as feeding, sexual behavior and circadian rhythms. The serotonergic and circadian systems are intertwined. Serotonin leads to reduced food intake and satiety and also has a wide range of physiological roles in mammals. Although the mechanism remains unclear, one of the side effects of long-term use of selective serotonin reuptake inhibitors (SSRIs) is weight gain. In the past years, research has been focused mainly on the role of serotonin in the brain, and its role in the periphery was greatly unappreciated. Our objective was to test the hypothesis that peripheral serotonin alters circadian rhythms leading to a shift towards fat synthesis and weight gain. We found that serotonin and/or the SSRI fluvoxamine led to fat accumulation in mouse liver, hepatocytes and white adipose tissue by shifting metabolism towards fatty acid synthesis and by disrupting circadian rhythms. We also found that serotonin leads to whitening of brown adipocytes and interferes with the differentiation process into brown adipocyte through TGF-β signaling and core clock proteins. Inhibition of the serotonergic system may be an effective treatment in reversing obesity and related clinical disorders such as NAFLD and type 2 diabetes.