The β₂-Adrenoceptor Agonist Formoterol Stimulates Mitochondrial Biogenesis

Abstract

Mitochondrial dysfunction is a common mediator of disease and organ injury. Although recent studies show that inducing mitochondrial biogenesis (MB) stimulates cell repair and regeneration, only a limited number of chemicals are known to induce MB. To examine the impact of the ␤-adrenoceptor (␤-AR) signaling pathway on MB, primary renal proximal tubule cells (RPTC) and adult feline cardiomyocytes were exposed for 24 h to multiple ␤-AR agonists: isoproter-, and formoterol (selective ␤ 2 -AR agonist). The Seahorse Biosciences (North Billerica, MA) extracellular flux analyzer was used to quantify carbonylcyanide p-trifluoromethoxyphenylhydrazone (FCCP)-uncoupled oxygen consumption rate (OCR), a marker of maximal electron transport chain activity. Isoproterenol and BRL 37244 did not alter mitochondrial respiration at any of the concentrations examined. Formoterol exposure resulted in increases in both FCCP-uncoupled OCR and mitochondrial DNA (mtDNA) copy number. The effect of formoterol on OCR in RPTC was inhibited by the ␤-AR antagonist propranolol and the ␤ 2 -AR inverse agonist 3-(isopropylamino)-1-[(7-methyl-4-indanyl)oxy]butan-2-ol hydrochloride (ICI-118,551). Mice exposed to formoterol for 24 or 72 h exhibited increases in kidney and heart mtDNA copy number, peroxisome proliferator-activated receptor ␥ coactivator 1␣, and multiple genes involved in the mitochondrial electron transport chain (F0 subunit 6 of transmembrane F-type ATP synthase, NADH dehydrogenase subunit 1, NADH dehydrogenase subunit 6, and NADH dehydrogenase [ubiquinone] 1␤ subcomplex subunit 8). Cheminformatic modeling, virtual chemical library screening, and experimental validation identified nisoxetine from the Sigma Library of Pharmacologically Active Compounds and two compounds from the ChemBridge DIVERSet that increased mitochondrial respiratory capacity. These data provide compelling evidence for the use and development of ␤ 2 -AR ligands for therapeutic MB.

5-HT2 Receptor Regulation of Mitochondrial Genes: Unexpected Pharmacological Effects of Agonists and Antagonists

“…RPTCs were plated in XF-96 plates and grown under improved culture conditions that maintain polarity, differentiated function, and respiration rates similar to in vivo RPTCs Schnellmann, 1995, 1996;Wills et al, 2012). RPTCs were treated for 24 hours with either vehicle control (0.5% dimethylsulfoxide), CP-809,101 (selective 5-HT 2C agonist), or SB-242,084 (selective 5-HT 2C antagonist).…”

“…Our drug discovery program in MB has previously identified several pharmacological targets that activate PGC-1a and induce MB, including the b 2 adrenergic receptor, phosphodiesterases inhibitors, and the 5-HT 2 class of receptors (Rasbach et al, 2010;Wills et al, 2012). Of these targets, the role of the 5-HT 2 receptor in mitochondrial signaling has been explored the least.…”

Adrenergic control of pinealocyte chondriome – an in vitro study

“…Another agonist of beta 2 -adrenoceptors, formoterol, stimulated mitochondrial biogenesis in cultured adult feline cardiomyocytes (Wills et al 2012) and rabbit renal tubule cells (Wills et al 2012, Peterson et al 2013. Interestingly, isoproterenol and NE were ineffective in these in vitro models (Wills et al 2012, Peterson et al 2013. It has been demonstrated that the betaadrenoceptor pathway enhances mitochondrial function in human neural stem cells (Chiang 2012).…”

“…The in vivo administration of clenbuterol, a beta 2 -adrenoceptor agonist, induced prominent ultrastructural changes in mitochondria in the skeletal muscle of mice (Sundal and Sharma 2007). Another agonist of beta 2 -adrenoceptors, formoterol, stimulated mitochondrial biogenesis in cultured adult feline cardiomyocytes (Wills et al 2012) and rabbit renal tubule cells (Wills et al 2012, Peterson et al 2013. Interestingly, isoproterenol and NE were ineffective in these in vitro models (Wills et al 2012, Peterson et al 2013.…”

“…The role of adrenergic receptors in mitochondrial biogenesis and function has been the subject of many investigations performed on various cell types (Chiang et al 2012, Wills et al 2012, Branco et al 2013, Peterson et al 2013, Pennanen et al 2014. The aim of the present study was to characterize the effect of NE as well as β-and α 1 -adrenergic agonists on mitochondria in pig pinealocytes in organ culture.…”