TY - JOUR
T1 - Soluble adenylyl cyclase regulates the cytosolic NADH/NAD+ redox state and the bioenergetic switch between glycolysis and oxidative phosphorylation
AU - Chang, Jung-Chin
AU - Go, Simei
AU - Gilglioni, Eduardo H.
AU - Duijst, Suzanne
AU - Panneman, Daan M.
AU - Rodenburg, Richard J.
AU - Li, Hang Lam
AU - Huang, Hsu-Li
AU - Levin, Lonny R.
AU - Buck, Jochen
AU - Verhoeven, Arthur J.
AU - Oude Elferink, Ronald P. J.
N1 - Funding Information: Ronald Oude Elferink and Jung-Chin Chang are supported by grant #11652-2018-1 from the Dutch Cancer Society (KWF/Alpe d'HuZes). Jung-Chin Chang is also supported by AGEM Talent development Grant of the Amsterdam Gastroenterology, Endocrinology & Metabolism Research Institute. Jochen Buck and Lonny Levin are supported by NIH grants AG061290 and HD088571. The authors thank Dr. D. de Korte (Sanquin Blood Foundation, Amsterdam, NL) for performing the analysis of adenylate nucleotides and Dr. Michel van Weeghel of the Amsterdam UMC Metabolomics Core for performing and analyzing the metabolomics experiment. JCC, AJV and ROE developed the study concept. JCC, SG, EHG, SD, HLL, HSH, DMP, RJR, and AJV designed, performed, and analyzed the experiments. JB and LRL provided insights in study design and interpretation. JCC drafted the manuscript. All co-authors commented and reviewed the manuscript and agreed with their authorship. Funding Information: Ronald Oude Elferink and Jung-Chin Chang are supported by grant # 11652-2018-1 from the Dutch Cancer Society (KWF/Alpe d'HuZes). Jung-Chin Chang is also supported by AGEM Talent development Grant of the Amsterdam Gastroenterology, Endocrinology & Metabolism Research Institute . Jochen Buck and Lonny Levin are supported by NIH grants AG061290 and HD088571 . The authors thank Dr. D. de Korte (Sanquin Blood Foundation, Amsterdam, NL) for performing the analysis of adenylate nucleotides and Dr. Michel van Weeghel of the Amsterdam UMC Metabolomics Core for performing and analyzing the metabolomics experiment. Publisher Copyright: © 2020 The Author(s)
PY - 2021/4/1
Y1 - 2021/4/1
N2 - The evolutionarily conserved soluble adenylyl cyclase (sAC, ADCY10) mediates cAMP signaling exclusively in intracellular compartments. Because sAC activity is sensitive to local concentrations of ATP, bicarbonate, and free Ca2+, sAC is potentially an important metabolic sensor. Nonetheless, little is known about how sAC regulates energy metabolism in intact cells. In this study, we demonstrated that both pharmacological and genetic suppression of sAC resulted in increased lactate secretion and decreased pyruvate secretion in multiple cell lines and primary cultures of mouse hepatocytes and cholangiocytes. The increased extracellular lactate-to-pyruvate ratio upon sAC suppression reflected an increased cytosolic free [NADH]/[NAD+] ratio, which was corroborated by using the NADH/NAD+ redox biosensor Peredox-mCherry. Mechanistic studies in permeabilized HepG2 cells showed that sAC inhibition specifically suppressed complex I of the mitochondrial respiratory chain. A survey of cAMP effectors revealed that only selective inhibition of exchange protein activated by cAMP 1 (Epac1), but not protein kinase A (PKA) or Epac2, suppressed complex I-dependent respiration and significantly increased the cytosolic NADH/NAD+ redox state. Analysis of the ATP production rate and the adenylate energy charge showed that inhibiting sAC reciprocally affects ATP production by glycolysis and oxidative phosphorylation while maintaining cellular energy homeostasis. In conclusion, our study shows that, via the regulation of complex I-dependent mitochondrial respiration, sAC-Epac1 signaling regulates the cytosolic NADH/NAD+ redox state, and coordinates oxidative phosphorylation and glycolysis to maintain cellular energy homeostasis. As such, sAC is effectively a bioenergetic switch between aerobic glycolysis and oxidative phosphorylation at the post-translational level.
AB - The evolutionarily conserved soluble adenylyl cyclase (sAC, ADCY10) mediates cAMP signaling exclusively in intracellular compartments. Because sAC activity is sensitive to local concentrations of ATP, bicarbonate, and free Ca2+, sAC is potentially an important metabolic sensor. Nonetheless, little is known about how sAC regulates energy metabolism in intact cells. In this study, we demonstrated that both pharmacological and genetic suppression of sAC resulted in increased lactate secretion and decreased pyruvate secretion in multiple cell lines and primary cultures of mouse hepatocytes and cholangiocytes. The increased extracellular lactate-to-pyruvate ratio upon sAC suppression reflected an increased cytosolic free [NADH]/[NAD+] ratio, which was corroborated by using the NADH/NAD+ redox biosensor Peredox-mCherry. Mechanistic studies in permeabilized HepG2 cells showed that sAC inhibition specifically suppressed complex I of the mitochondrial respiratory chain. A survey of cAMP effectors revealed that only selective inhibition of exchange protein activated by cAMP 1 (Epac1), but not protein kinase A (PKA) or Epac2, suppressed complex I-dependent respiration and significantly increased the cytosolic NADH/NAD+ redox state. Analysis of the ATP production rate and the adenylate energy charge showed that inhibiting sAC reciprocally affects ATP production by glycolysis and oxidative phosphorylation while maintaining cellular energy homeostasis. In conclusion, our study shows that, via the regulation of complex I-dependent mitochondrial respiration, sAC-Epac1 signaling regulates the cytosolic NADH/NAD+ redox state, and coordinates oxidative phosphorylation and glycolysis to maintain cellular energy homeostasis. As such, sAC is effectively a bioenergetic switch between aerobic glycolysis and oxidative phosphorylation at the post-translational level.
KW - Exchange protein directly activated by cAMP (Epac)
KW - Glycolysis
KW - NADH/NAD redox state
KW - Oxidative phosphorylation
KW - Protein kinase A
KW - Soluble adenylyl cyclase
UR - http://www.scopus.com/inward/record.url?scp=85099348493&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.bbabio.2020.148367
DO - https://doi.org/10.1016/j.bbabio.2020.148367
M3 - Article
C2 - 33412125
SN - 0005-2728
VL - 1862
JO - BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS
JF - BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS
IS - 4
M1 - 148367
ER -