Université Nice Côte d'Azur, Inserm U1065, C3M, Team Cellular and Molecular Physiopathology of Obesity, Nice, France.
Université Nice Côte d'Azur, Inserm U1065, C3M, Team " Study of the melanocytic differentiation applied to vitiligo and melanoma: from the patient to the molecular mechanisms", Nice, France.
Sci Rep. 2017 Aug 1;7(1):7023. doi: 10.1038/s41598-017-07182-z.
In response to endotoxemia, the organism triggers an inflammatory response, and the visceral adipose tissue represents a major source of proinflammatory cytokines. The regulation of inflammation response in the adipose tissue is thus of crucial importance. We demonstrated that Regulated in development and DNA damage response-1 (REDD1) is involved in inflammation. REDD1 expression was increased in response to lipopolysaccharide (LPS) in bone marrow derived macrophages (BMDM) and in epidydimal adipose tissue. Loss of REDD1 protected the development of inflammation, since the expression of proinflammatory cytokines (TNFα, IL-6, IL-1β) was decreased in adipose tissue of REDD1 mice injected with LPS compared to wild-type mice. This decrease was associated with an inhibition of the activation of p38MAPK, JNK, NF-κB and NLRP3 inflammasome leading to a reduction of IL-1β secretion in response to LPS and ATP in REDD1 BMDM. Although REDD1 is an inhibitor of mTORC1, loss of REDD1 decreased inflammation independently of mTORC1 activation but more likely through oxidative stress regulation. Absence of REDD1 decreases ROS associated with a dysregulation of Nox-1 and GPx3 expression. Absence of REDD1 in macrophages decreases the development of insulin resistance in adipocyte-macrophage coculture. Altogether, REDD1 appears to be a key player in the control of inflammation.
针对内毒素血症,机体引发炎症反应,而内脏脂肪组织则是促炎细胞因子的主要来源。因此,脂肪组织中炎症反应的调节至关重要。我们发现调控发育和 DNA 损伤反应蛋白 1(REDD1)参与了炎症反应。REDD1 的表达在骨髓来源的巨噬细胞(BMDM)和附睾脂肪组织中受到脂多糖(LPS)的刺激而增加。REDD1 的缺失保护了炎症的发展,因为与野生型小鼠相比,注射 LPS 的 REDD1 小鼠的脂肪组织中促炎细胞因子(TNFα、IL-6、IL-1β)的表达减少。这种减少与 p38MAPK、JNK、NF-κB 和 NLRP3 炎症小体的激活抑制有关,导致 LPS 和 ATP 刺激下 REDD1 BMDM 中 IL-1β 的分泌减少。尽管 REDD1 是 mTORC1 的抑制剂,但 REDD1 的缺失减少炎症的发生与 mTORC1 的激活无关,而更可能是通过氧化应激的调节。REDD1 的缺失减少了与 Nox-1 和 GPx3 表达失调相关的 ROS。巨噬细胞中 REDD1 的缺失减少了脂肪细胞-巨噬细胞共培养物中胰岛素抵抗的发展。总之,REDD1 似乎是控制炎症的关键因素。