Urolithin A augments angiogenic pathways in skeletal muscle by bolstering NAD+ and SIRT1

Abstract

Urolithin A (UA) is a natural compound that is known to improve muscle function. In this work we sought to evaluate the effect of UA on muscle angiogenesis and identify the underlying molecular mechanisms. C57BL/6 mice were administered with UA (10 mg/body weight) for 12–16 weeks. ATP levels and NAD+ levels were measured using in vivo 31P NMR and HPLC, respectively. UA significantly increased ATP and NAD+ levels in mice skeletal muscle. Unbiased transcriptomics analysis followed by Ingenuity Pathway Analysis (IPA) revealed upregulation of angiogenic pathways upon UA supplementation in murine muscle. The expression of the differentially regulated genes were validated using quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC). Angiogenic markers such as VEGFA and CDH5 which were blunted in skeletal muscles of 28 week old mice were found to be upregulated upon UA supplementation. Such augmentation of skeletal muscle vascularization was found to be bolstered via Silent information regulator 1 (SIRT1) and peroxisome proliferator-activated receptor-gamma coactivator-1-alpha (PGC-1α) pathway. Inhibition of SIRT1 by selisistat EX527 blunted UA-induced angiogenic markers in C2C12 cells. Thus this work provides maiden evidence demonstrating that UA supplementation bolsters skeletal muscle ATP and NAD+ levels causing upregulated angiogenic pathways via a SIRT1-PGC-1α pathway.

Effects of Urolithin A on Mitochondrial Parameters in a Cellular Model of Early Alzheimer Disease

“…Next to increased PGC1α gene expression, Andreux et al also found that 1000 mg/day UA led to significant increases of ESRRα and significantly higher mitochondrial mass in subjects’ skeletal muscle [ 37 ]. In skeletal muscle myoblasts of C57BL/6 mice treated with 10 mg/kg bodyweight UA, Ghosh et al found increased PGC1α and SIRT1 expression, as well as increased ATP levels [ 39 ]. Since it is not unambiguously clear in which way PGC1a was or was not affected due to its short half-life, alternatives should be considered.…”

“…Low doses of UA have also been reported to provide neuroprotection against H 2 O 2 induced oxidative stress in N2a [ 33 ] and SH-SY5Y [ 34 , 35 ] cells. Furthermore, multiple studies also reported increased mitochondrial function and enhanced mitochondrial biogenesis facilitated by UA [ 27 , 36 , 37 , 38 , 39 ].…”

Hengshun Aromatic Vinegar Ameliorates Vascular Endothelial Injury via Regulating PKCζ-Mediated Oxidative Stress and Apoptosis

“…PKCζ can regulate the activity of Sirt1, which is a deacetylating enzyme of NAD + depletion that has significant antioxidant activity by deacetylating various substrates involved in gene silencing, cell cycle, and aging processes (40). The activation of Sirt1 can significantly improve endothelial function in aged mice (41), decrease the expression of Keap1 that can lead to the dissociation and nuclear translocation of Nrf2, activate Keap1/Nrf2 antioxidant pathway, and thus activate the transcriptions of a variety of antioxidant genes, including NQO1 and GST (42,43). Therefore, inhibition of PKCζ can decrease the production of ROS and alleviate oxidative stress through regulating Sirt1 pathway.…”

Impact of the Natural Compound Urolithin A on Health, Disease, and Aging

“…When administered intragastrically to middle-aged mice for 16 weeks, UA increased markers of angiogenesis in the skeletal muscle [37]. Although no functional data were provided, this is a relevant observation, as impaired neovascularization plays an important role in muscle aging diseases [38].…”