Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ, 85721, USA.
Department of Drug Discovery and Biomedical Sciences, College of Graduate Studies, Medical University of South Carolina, Charleston, SC, 29425, USA.
Sci Rep. 2017 Sep 5;7(1):10578. doi: 10.1038/s41598-017-11030-5.
Mitochondrial dysfunction is associated with numerous acute and chronic degenerative diseases. The beta-2 adrenergic receptor (βAR) agonist formoterol induces mitochondrial biogenesis (MB), but other βAR agonists, such as clenbuterol, do not. We sought to identify the MB signaling pathway of formoterol and the differences in signaling between these two ligands that result in the differential induction of MB. While formoterol and clenbuterol increased cAMP, only formoterol increased the phosphorylation of Akt and its downstream target eNOS. The increase in Akt phosphorylation was Gβγ- and PI3K-dependent, and the increase in eNOS phosphorylation was Gβγ- and Akt-dependent. Only formoterol increased cGMP. Formoterol induced MB as measured by increases in uncoupled cellular respiration and PGC-1α and NDUFS1 mRNA expression and was blocked by inhibitors of Gβγ, Akt, NOS, and soluble guanylate cyclase. To identify distinct receptor-ligand interactions leading to these differences in signaling, we docked formoterol and clenbuterol to six structures of the βAR. Compared to clenbuterol, the methoxyphenyl group of formoterol interacted more frequently with V114 and F193, while its formamide group interacted more frequently with C191. These data indicate that the unique structural features of formoterol allow it to interact with the βAR to activate the Gβγ-Akt-eNOS-sGC pathway to induce MB.
线粒体功能障碍与许多急性和慢性退行性疾病有关。β2 肾上腺素能受体 (βAR) 激动剂福莫特罗可诱导线粒体生物发生 (MB)，但其他 βAR 激动剂，如克仑特罗则不能。我们试图确定福莫特罗的 MB 信号通路以及这两种配体在信号转导方面的差异，这些差异导致 MB 的不同诱导。虽然福莫特罗和克仑特罗均可增加 cAMP，但只有福莫特罗可增加 Akt 的磷酸化及其下游靶标 eNOS。Akt 磷酸化的增加依赖于 Gβγ 和 PI3K，而 eNOS 磷酸化的增加依赖于 Gβγ 和 Akt。只有福莫特罗可增加 cGMP。福莫特罗可诱导 MB，其指标为未偶联细胞呼吸增加以及 PGC-1α 和 NDUFS1 mRNA 表达增加，且可被 Gβγ、Akt、NOS 和可溶性鸟苷酸环化酶抑制剂阻断。为了确定导致这些信号转导差异的不同受体-配体相互作用，我们将福莫特罗和克仑特罗对接至βAR 的六种结构。与克仑特罗相比，福莫特罗的甲氧基苯基团与 V114 和 F193 的相互作用更频繁，而其甲酰胺基团与 C191 的相互作用更频繁。这些数据表明，福莫特罗的独特结构特征使其能够与βAR 相互作用，激活 Gβγ-Akt-eNOS-sGC 通路，从而诱导 MB。
