Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL, USA.
Mol Metab. 2018 Mar;9:28-42. doi: 10.1016/j.molmet.2018.01.017. Epub 2018 Feb 3.
The peroxisome proliferator-activated receptor-γ coactivator-1α1 (PGC-1α1) regulates genes involved in energy metabolism. Increasing adipose tissue energy expenditure through PGC-1α1 activation is potentially beneficial for systemic metabolism. Pharmacological PGC-1α1 activators could be valuable tools in the fight against obesity and metabolic disease. Finding such compounds has been challenging partly because PGC-1α1 is a transcriptional coactivator with no known ligand-binding properties. While, PGC-1α1 activation is regulated by several mechanisms, protein stabilization is a crucial limiting step due to its short half-life under unstimulated conditions.
We designed a cell-based high-throughput screening system to identify PGC-1α1 protein stabilizers. Positive hits were tested for their ability to induce endogenous PGC-1α1 protein accumulation and activate target gene expression in brown adipocytes. Select compounds were analyzed for their effects on global gene expression and cellular respiration in adipocytes.
Among 7,040 compounds screened, we highlight four small molecules with high activity as measured by: PGC-1α1 protein accumulation, target gene expression, and uncoupled mitochondrial respiration in brown adipocytes.
We identify compounds that induce PGC-1α1 protein accumulation and show that this increases uncoupled respiration in brown adipocytes. This screening platform establishes the foundation for a new class of therapeutics with potential use in obesity and associated disorders.
过氧化物酶体增殖物激活受体γ共激活因子-1α1（PGC-1α1）调节参与能量代谢的基因。通过激活 PGC-1α1 增加脂肪组织的能量消耗，对全身代谢可能有益。PGC-1α1 激活的药理学激动剂可能是对抗肥胖和代谢疾病的有价值的工具。寻找此类化合物具有挑战性，部分原因是 PGC-1α1 是一种没有已知配体结合特性的转录共激活剂。虽然，PGC-1α1 的激活受到几种机制的调节，但由于其在未受刺激条件下的半衰期短，蛋白稳定化是一个关键的限制步骤。
我们设计了一种基于细胞的高通量筛选系统，以鉴定 PGC-1α1 蛋白稳定剂。阳性命中物被测试其诱导内源性 PGC-1α1 蛋白积累并激活棕色脂肪细胞中靶基因表达的能力。选择的化合物被分析其对脂肪细胞中全局基因表达和细胞呼吸的影响。
在筛选的 7040 种化合物中，我们重点介绍了四种具有高活性的小分子，如：PGC-1α1 蛋白积累、靶基因表达和棕色脂肪细胞中解偶联的线粒体呼吸。
我们鉴定了诱导 PGC-1α1 蛋白积累的化合物，并表明这增加了棕色脂肪细胞中解偶联的呼吸。该筛选平台为一类具有肥胖和相关疾病潜在用途的新型治疗药物奠定了基础。
