PGC-1alpha integrates insulin signaling, mitochondrial regulation, and bioenergetic function in skeletal muscle - PubMed (original) (raw)
PGC-1alpha integrates insulin signaling, mitochondrial regulation, and bioenergetic function in skeletal muscle
Ines Pagel-Langenickel et al. J Biol Chem. 2008.
Abstract
The pathophysiology underlying mitochondrial dysfunction in insulin-resistant skeletal muscle is incompletely characterized. To further delineate this we investigated the interaction between insulin signaling, mitochondrial regulation, and function in C2C12 myotubes and in skeletal muscle. In myotubes elevated insulin and glucose disrupt insulin signaling, mitochondrial biogenesis, and mitochondrial bioenergetics. The insulin-sensitizing thiazolidinedione pioglitazone restores these perturbations in parallel with induction of the mitochondrial biogenesis regulator PGC-1alpha. Overexpression of PGC-1alpha rescues insulin signaling and mitochondrial bioenergetics, and its silencing concordantly disrupts insulin signaling and mitochondrial bioenergetics. In primary skeletal myoblasts pioglitazone also up-regulates PGC-1alpha expression and restores the insulin-resistant mitochondrial bioenergetic profile. In parallel, pioglitazone up-regulates PGC-1alpha in db/db mouse skeletal muscle. Interestingly, the small interfering RNA knockdown of the insulin receptor in C2C12 myotubes down-regulates PGC-1alpha and attenuates mitochondrial bioenergetics. Concordantly, mitochondrial bioenergetics are blunted in insulin receptor knock-out mouse-derived skeletal myoblasts. Taken together these data demonstrate that elevated glucose and insulin impairs and pioglitazone restores skeletal myotube insulin signaling, mitochondrial regulation, and bioenergetics. Pioglitazone functions in part via the induction of PGC-1alpha. Moreover, PGC-1alpha is identified as a bidirectional regulatory link integrating insulin-signaling and mitochondrial homeostasis in skeletal muscle.
Figures
FIGURE 1.
Insulin signaling and mitochondrial phenotype in response to insulin resistance and pioglitazone. Control myotubes were exposed to 25 m
m
glucose, and the insulin resistant myotubes were exposed to 40 m
m
glucose and 100 n
m
insulin for 48 h. A represents insulin-responsive signaling as shown by the representative Western blots (pTyr, phosphotyrosine; cont, control; IR, insulin resistance). B, transcript levels, expressed as % control, of genes encoding for mitochondrial regulatory proteins (PPAR_γ, peroxisome proliferator-activated receptor γ; NRF1, nuclear respiratory factor 1; Tfam, mitochondrial transcription factor A and SIRT1. C, steady-state mitochondrial electron transfer chain protein levels (COX I and III, cytochrome c oxidase subunits I and III;Cyt c, cytochrome c; ND 6, NADH dehydrogenase, subunit 6;VDAC, voltage-dependent anion channel) as well as levels of voltage-activated anion channel, SIRT1, and actin as a housekeeping protein;D, relative mitochondrial genomic copy number (% control). E shows insulin-responsive signaling comparing insulin-resistant to pioglitazone (Pio)-treated insulin-resistant myotubes. F, transcript levels, expressed as % control, of genes encoding for mitochondrial regulatory proteins. G, steady-state mitochondrial electron transfer chain protein levels comparing insulin-resistant to insulin-resistant myotubes exposed to pioglitazone. H, relative mitochondrial genomic copy number (% control). The asterisk represents a p < 0.05_versus the respective control in this and all subsequent figures (unless otherwise stated).
FIGURE 2.
Insulin resistance and pioglitazone modulation of mitochondrial biology. The mitochondrial bioenergetic profile was compared between control and insulin-resistant myotubes and to the administration of pioglitazone. Results are representative cytometric profile of MitoTracker green, which represents that relative mitochondrial size (A), and tetramethylrhodamine methyl ester (TMRM), which represents the relative mitochondrial membrane potential (% control) (B) comparing control to insulin-resistant cells. C, total cellular ATP levels.D, the relative rate of oxygen consumption (% control). E, comparing insulin resistant cells to those exposed to pioglitazone (Pio) showing a representative cytometric profile of MitoTracker green fluorescence depicting the relative mitochondrial size. F, tetramethylrhodamine methyl ester represents the relative mitochondrial membrane potential (% insulin-resistant controls). G, total cellular ATP levels. H, relative rate of oxygen consumption (% insulin-resistant controls). RFU, relative fluorescent units.
FIGURE 3.
Pioglitazone restores the mitochondrial bioenergetic profile in primary myocytes and in the db/db mouse. A, pioglitazone (Pio) up-regulates the expression of the gene encoding for PGC-1α in primary myoblasts. B, pioglitazone reverses the diminution in mitochondrial size and membrane potential evoked by insulin resistance in primary skeletal myoblasts. C, pioglitazone prevents the development of fasting hyperglycemia in db/db mice. D, pioglitazone up-regulates PGC-1α steady-state protein levels in db/db mice. The levels of PGC-1α were diminished in untreated db/db mice compared with strain-matched C57BL/6J control mice.
FIGURE 4.
PGC-1α modulates mitochondrial biology and insulin signaling. A shows murine PGC-1α promoter activation in response to pioglitazone (cont, control; Pio, pioglitazone). B, infection of PGC-1α up-regulates PGC-1α and COX I protein levels.MOI, multiplicity of infection. C, augmentation of relative rate of oxygen consumption in cells with increasing levels of PGC-1α and the relative O2 consumption comparing GFP to PGC-1α vector at a multiplicity of infection of 100. D shows the restoration of insulin-mediated signaling (% GFP/cont without insulin) by PGC-1α overexpression (pTyr, phosphotyrosine; cont, control).E, induction of oxygen consumption by PGC1α overexpression in, insulin resistance myotubes. F, effect of PGC-1α silencing on transcript levels and on oxygen consumption (% si cont); G, the diminution of Akt threonine phosphorylation by insulin after partial silencing of PGC-1α.
FIGURE 5.
Disruption of insulin signaling and mitochondrial respiration. A, effect of knockdown of InsRβ on Akt phosphorylation (p-Akt). B, PGC-1α levels in response to knockdown of InsRβ. C, quantitative reduction of PGC-1α protein after InsRβ knockdown. D, attenuation in mitochondrial size and membrane potential in insulin receptor knockdown cells. TMRM, tetramethylrhodamine methyl ester; Mito G, MitoTracker green.E, in insulin receptor knock-out (KO) skeletal myoblasts the mitochondrial membrane potential and mitochondrial mass is diminished compared with wild type (WT) control cells.
Similar articles
- The PGC-1α-related coactivator promotes mitochondrial and myogenic adaptations in C2C12 myotubes.
Philp A, Belew MY, Evans A, Pham D, Sivia I, Chen A, Schenk S, Baar K. Philp A, et al. Am J Physiol Regul Integr Comp Physiol. 2011 Oct;301(4):R864-72. doi: 10.1152/ajpregu.00232.2011. Epub 2011 Jul 27. Am J Physiol Regul Integr Comp Physiol. 2011. PMID: 21795630 Free PMC article. - Mitochondrial biogenesis and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) deacetylation by physical activity: intact adipocytokine signaling is required.
Li L, Pan R, Li R, Niemann B, Aurich AC, Chen Y, Rohrbach S. Li L, et al. Diabetes. 2011 Jan;60(1):157-67. doi: 10.2337/db10-0331. Epub 2010 Oct 7. Diabetes. 2011. PMID: 20929977 Free PMC article. - PGC-1α-mediated regulation of mitochondrial function and physiological implications.
Halling JF, Pilegaard H. Halling JF, et al. Appl Physiol Nutr Metab. 2020 Sep;45(9):927-936. doi: 10.1139/apnm-2020-0005. Epub 2020 Jun 9. Appl Physiol Nutr Metab. 2020. PMID: 32516539 Review. - PGC-1alpha and exercise: important partners in combating insulin resistance.
Russell AP. Russell AP. Curr Diabetes Rev. 2005 May;1(2):175-81. doi: 10.2174/1573399054022811. Curr Diabetes Rev. 2005. PMID: 18220593 Review.
Cited by
- Potential molecular mechanism of exercise reversing insulin resistance and improving neurodegenerative diseases.
Shen J, Wang X, Wang M, Zhang H. Shen J, et al. Front Physiol. 2024 May 16;15:1337442. doi: 10.3389/fphys.2024.1337442. eCollection 2024. Front Physiol. 2024. PMID: 38818523 Free PMC article. Review. - Energy expenditure related biomarkers following bariatric surgery: a prospective six-month cohort study.
Hatami M, Javanbakht MH, Haghighat N, Sohrabi Z, Yavar R, Pazouki A, Farsani GM. Hatami M, et al. BMC Surg. 2024 Apr 27;24(1):129. doi: 10.1186/s12893-024-02421-3. BMC Surg. 2024. PMID: 38678284 Free PMC article. - Upregulation of PGC-1α expression by pioglitazone mediates prevention of sepsis-induced acute lung injury.
Tang J, Dong W, Wang D, Deng Q, Guo H, Xiao G. Tang J, et al. Braz J Med Biol Res. 2024 Mar 18;57:e13235. doi: 10.1590/1414-431X2024e13235. eCollection 2024. Braz J Med Biol Res. 2024. PMID: 38511769 Free PMC article. - Extracellular vesicles from obese and diabetic mouse plasma alter C2C12 myotube glucose uptake and gene expression.
Pitzer CR, Paez HG, Ferrandi PJ, Mohamed JS, Alway SE. Pitzer CR, et al. Physiol Rep. 2024 Jan;12(1):e15898. doi: 10.14814/phy2.15898. Physiol Rep. 2024. PMID: 38169108 Free PMC article. - Lasmiditan restores mitochondrial quality control mechanisms and accelerates renal recovery after ischemia-reperfusion injury.
Hurtado KA, Janda J, Schnellmann RG. Hurtado KA, et al. Biochem Pharmacol. 2023 Dec;218:115855. doi: 10.1016/j.bcp.2023.115855. Epub 2023 Oct 21. Biochem Pharmacol. 2023. PMID: 37866804
References
- Karlsson, H. K., Ahlsen, M., Zierath, J. R., Wallberg-Henriksson, H., and Koistinen, H. A. (2006) Diabetes 55 1283–1288 - PubMed
- Storgaard, H., Song, X. M., Jensen, C. B., Madsbad, S., Bjornholm, M., Vaag, A., and Zierath, J. R. (2001) Diabetes 50 2770–2778 - PubMed
- Patti, M. E., Butte, A. J., Crunkhorn, S., Cusi, K., Berria, R., Kashyap, S., Miyazaki, Y., Kohane, I., Costello, M., Saccone, R., Landaker, E. J., Goldfine, A. B., Mun, E., DeFronzo, R., Finlayson, J., Kahn, C. R., and Mandarino, L. J. (2003) Proc. Natl. Acad. Sci. U. S. A. 100 8466–8471 - PMC - PubMed
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Other Literature Sources
Medical
Molecular Biology Databases
Miscellaneous