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Thome T, Vugman NA, Stone LE, Wimberly K, Scali ST, Ryan TE. A tryptophan-derived uremic metabolite/Ahr/Pdk4 axis governs skeletal muscle mitochondrial energetics in chronic kidney disease. JCI Insight 2024; 9:e178372. [PMID: 38652558 PMCID: PMC11141944 DOI: 10.1172/jci.insight.178372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 04/12/2024] [Indexed: 04/25/2024] Open
Abstract
Chronic kidney disease (CKD) causes accumulation of uremic metabolites that negatively affect skeletal muscle. Tryptophan-derived uremic metabolites are agonists of the aryl hydrocarbon receptor (AHR), which has been shown to be activated in CKD. This study investigated the role of the AHR in skeletal muscle pathology of CKD. Compared with controls with normal kidney function, AHR-dependent gene expression (CYP1A1 and CYP1B1) was significantly upregulated in skeletal muscle of patients with CKD, and the magnitude of AHR activation was inversely correlated with mitochondrial respiration. In mice with CKD, muscle mitochondrial oxidative phosphorylation (OXPHOS) was markedly impaired and strongly correlated with the serum level of tryptophan-derived uremic metabolites and AHR activation. Muscle-specific deletion of the AHR substantially improved mitochondrial OXPHOS in male mice with the greatest uremic toxicity (CKD + probenecid) and abolished the relationship between uremic metabolites and OXPHOS. The uremic metabolite/AHR/mitochondrial axis in skeletal muscle was verified using muscle-specific AHR knockdown in C57BL/6J mice harboring a high-affinity AHR allele, as well as ectopic viral expression of constitutively active mutant AHR in mice with normal renal function. Notably, OXPHOS changes in AHRmKO mice were present only when mitochondria were fueled by carbohydrates. Further analyses revealed that AHR activation in mice led to significantly increased pyruvate dehydrogenase kinase 4 (Pdk4) expression and phosphorylation of pyruvate dehydrogenase enzyme. These findings establish a uremic metabolite/AHR/Pdk4 axis in skeletal muscle that governs mitochondrial deficits in carbohydrate oxidation during CKD.
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Affiliation(s)
- Trace Thome
- Department of Applied Physiology and Kinesiology and
| | | | | | - Keon Wimberly
- Department of Applied Physiology and Kinesiology and
| | - Salvatore T. Scali
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Florida, USA
- Malcom Randall VA Medical Center, Gainesville, Florida, USA
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology and
- Center for Exercise Science and
- Myology Institute, University of Florida, Gainesville, Florida, USA
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Palzkill VR, Tan J, Tice AL, Ferriera LF, Ryan TE. A 6-minute Limb Function Assessment for Therapeutic Testing in Experimental Peripheral Artery Disease Models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.21.586197. [PMID: 38585832 PMCID: PMC10996543 DOI: 10.1101/2024.03.21.586197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Background The translation of promising therapies from pre-clinical models of hindlimb ischemia (HLI) to patients with peripheral artery disease (PAD) has been inadequate. While this failure is multifactorial, primary outcome measures in preclinical HLI models and clinical trials involving patients with PAD are not aligned well. For example, laser Doppler perfusion recovery measured under resting conditions is the most used outcome in HLI studies, whereas clinical trials involving patients with PAD primarily assess walking performance. Here, we sought to develop a 6-min limb function test for preclinical HLI models that assess muscular performance and hemodynamics congruently. Methods We developed an in situ 6-min limb function test that involves repeated isotonic (shortening) contractions performed against a submaximal load. Continuous measurement of muscle blood flow was performed using laser Doppler flowmetry. Quantification of muscle power, work, and perfusion are obtained across the test. To assess the efficacy of this test, we performed HLI via femoral artery ligation on several mouse strains: C57BL6J, BALBc/J, and MCK-PGC1α (muscle-specific overexpression of PGC1α). Additional experiments were performed using an exercise intervention (voluntary wheel running) following HLI. Results The 6-min limb function test was successful at detecting differences in limb function of C57BL6/J and BALBc/J mice subjected to HLI with effect sizes superior to laser Doppler perfusion recovery. C57BL6/J mice randomized to exercise therapy following HLI had smaller decline in muscle power, greater hyperemia, and performed more work across the 6-min limb function test compared to non-exercise controls with HLI. Mice with muscle-specific overexpression of PGC1α had no differences in perfusion recovery in resting conditions, but exhibited greater capillary density, increased muscle mass and absolute force levels, and performed more work across the 6-min limb function test compared to their wildtype littermates without the transgene. Conclusion These results demonstrate the efficacy of the 6-min limb function test to detect differences in the response to HLI across several interventions including where traditional perfusion recovery, capillary density, and muscle strength measures were unable to detect therapeutic differences.
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Affiliation(s)
- Victoria R. Palzkill
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Jianna Tan
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | | | - Leonardo F. Ferriera
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
- Center for Exercise Science, The University of Florida, Gainesville, FL, USA
- The Myology Institute, The University of Florida, Gainesville, FL, USA
- Department of Orthopaedic Surgery, Duke University School of Medicine, Durham, NC, USA
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
- Center for Exercise Science, The University of Florida, Gainesville, FL, USA
- The Myology Institute, The University of Florida, Gainesville, FL, USA
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Pass CG, Palzkill V, Tan J, Kim K, Thome T, Yang Q, Fazzone B, Robinson ST, O’Malley KA, Yue F, Scali ST, Berceli SA, Ryan TE. Single-Nuclei RNA-Sequencing of the Gastrocnemius Muscle in Peripheral Artery Disease. Circ Res 2023; 133:791-809. [PMID: 37823262 PMCID: PMC10599805 DOI: 10.1161/circresaha.123.323161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 09/22/2023] [Accepted: 09/26/2023] [Indexed: 10/13/2023]
Abstract
BACKGROUND Lower extremity peripheral artery disease (PAD) is a growing epidemic with limited effective treatment options. Here, we provide a single-nuclei atlas of PAD limb muscle to facilitate a better understanding of the composition of cells and transcriptional differences that comprise the diseased limb muscle. METHODS We obtained gastrocnemius muscle specimens from 20 patients with PAD and 12 non-PAD controls. Nuclei were isolated and single-nuclei RNA-sequencing was performed. The composition of nuclei was characterized by iterative clustering via principal component analysis, differential expression analysis, and the use of known marker genes. Bioinformatics analysis was performed to determine differences in gene expression between PAD and non-PAD nuclei, as well as subsequent analysis of intercellular signaling networks. Additional histological analyses of muscle specimens accompany the single-nuclei RNA-sequencing atlas. RESULTS Single-nuclei RNA-sequencing analysis indicated a fiber type shift with patients with PAD having fewer type I (slow/oxidative) and more type II (fast/glycolytic) myonuclei compared with non-PAD, which was confirmed using immunostaining of muscle specimens. Myonuclei from PAD displayed global upregulation of genes involved in stress response, autophagy, hypoxia, and atrophy. Subclustering of myonuclei also identified populations that were unique to PAD muscle characterized by metabolic dysregulation. PAD muscles also displayed unique transcriptional profiles and increased diversity of transcriptomes in muscle stem cells, regenerating myonuclei, and fibro-adipogenic progenitor cells. Analysis of intercellular communication networks revealed fibro-adipogenic progenitors as a major signaling hub in PAD muscle, as well as deficiencies in angiogenic and bone morphogenetic protein signaling which may contribute to poor limb function in PAD. CONCLUSIONS This reference single-nuclei RNA-sequencing atlas provides a comprehensive analysis of the cell composition, transcriptional signature, and intercellular communication pathways that are altered in the PAD condition.
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Affiliation(s)
- Caroline G. Pass
- Department of Applied Physiology and Kinesiology (C.G.P., V.P., J.T., K.K., T.T., Q.Y., T.E.R.), The University of Florida, Gainesville
| | - Victoria Palzkill
- Department of Applied Physiology and Kinesiology (C.G.P., V.P., J.T., K.K., T.T., Q.Y., T.E.R.), The University of Florida, Gainesville
| | - Jianna Tan
- Department of Applied Physiology and Kinesiology (C.G.P., V.P., J.T., K.K., T.T., Q.Y., T.E.R.), The University of Florida, Gainesville
| | - Kyoungrae Kim
- Department of Applied Physiology and Kinesiology (C.G.P., V.P., J.T., K.K., T.T., Q.Y., T.E.R.), The University of Florida, Gainesville
| | - Trace Thome
- Department of Applied Physiology and Kinesiology (C.G.P., V.P., J.T., K.K., T.T., Q.Y., T.E.R.), The University of Florida, Gainesville
| | - Qingping Yang
- Department of Applied Physiology and Kinesiology (C.G.P., V.P., J.T., K.K., T.T., Q.Y., T.E.R.), The University of Florida, Gainesville
| | - Brian Fazzone
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy (B.F., S.T.R., K.A.O., S.T.S., S.A.B.), The University of Florida, Gainesville
- Malcom Randall VA Medical Center, Gainesville, FL (B.F., S.T.R., K.A.O., S.T.S., S.A.B.)
| | - Scott T. Robinson
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy (B.F., S.T.R., K.A.O., S.T.S., S.A.B.), The University of Florida, Gainesville
- Malcom Randall VA Medical Center, Gainesville, FL (B.F., S.T.R., K.A.O., S.T.S., S.A.B.)
| | - Kerri A. O’Malley
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy (B.F., S.T.R., K.A.O., S.T.S., S.A.B.), The University of Florida, Gainesville
- Malcom Randall VA Medical Center, Gainesville, FL (B.F., S.T.R., K.A.O., S.T.S., S.A.B.)
| | - Feng Yue
- Department of Animal Sciences (F.Y.), The University of Florida, Gainesville
- Myology Institute (F.Y., T.E.R.), The University of Florida, Gainesville
| | - Salvatore T. Scali
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy (B.F., S.T.R., K.A.O., S.T.S., S.A.B.), The University of Florida, Gainesville
- Malcom Randall VA Medical Center, Gainesville, FL (B.F., S.T.R., K.A.O., S.T.S., S.A.B.)
| | - Scott A. Berceli
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy (B.F., S.T.R., K.A.O., S.T.S., S.A.B.), The University of Florida, Gainesville
- Malcom Randall VA Medical Center, Gainesville, FL (B.F., S.T.R., K.A.O., S.T.S., S.A.B.)
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology (C.G.P., V.P., J.T., K.K., T.T., Q.Y., T.E.R.), The University of Florida, Gainesville
- Center for Exercise Science (T.E.R.), The University of Florida, Gainesville
- Myology Institute (F.Y., T.E.R.), The University of Florida, Gainesville
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Balestrieri N, Palzkill V, Pass C, Tan J, Salyers ZR, Moparthy C, Murillo A, Kim K, Thome T, Yang Q, O’Malley KA, Berceli SA, Yue F, Scali ST, Ferreira LF, Ryan TE. Activation of the Aryl Hydrocarbon Receptor in Muscle Exacerbates Ischemic Pathology in Chronic Kidney Disease. Circ Res 2023; 133:158-176. [PMID: 37325935 PMCID: PMC10330629 DOI: 10.1161/circresaha.123.322875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 06/07/2023] [Indexed: 06/17/2023]
Abstract
BACKGROUND Chronic kidney disease (CKD) accelerates the development of atherosclerosis, decreases muscle function, and increases the risk of amputation or death in patients with peripheral artery disease (PAD). However, the mechanisms underlying this pathobiology are ill-defined. Recent work has indicated that tryptophan-derived uremic solutes, which are ligands for AHR (aryl hydrocarbon receptor), are associated with limb amputation in PAD. Herein, we examined the role of AHR activation in the myopathy of PAD and CKD. METHODS AHR-related gene expression was evaluated in skeletal muscle obtained from mice and human PAD patients with and without CKD. AHRmKO (skeletal muscle-specific AHR knockout) mice with and without CKD were subjected to femoral artery ligation, and a battery of assessments were performed to evaluate vascular, muscle, and mitochondrial health. Single-nuclei RNA sequencing was performed to explore intercellular communication. Expression of the constitutively active AHR was used to isolate the role of AHR in mice without CKD. RESULTS PAD patients and mice with CKD displayed significantly higher mRNA expression of classical AHR-dependent genes (Cyp1a1, Cyp1b1, and Aldh3a1) when compared with either muscle from the PAD condition with normal renal function (P<0.05 for all 3 genes) or nonischemic controls. AHRmKO significantly improved limb perfusion recovery and arteriogenesis, preserved vasculogenic paracrine signaling from myofibers, increased muscle mass and strength, as well as enhanced mitochondrial function in an experimental model of PAD/CKD. Moreover, viral-mediated skeletal muscle-specific expression of a constitutively active AHR in mice with normal kidney function exacerbated the ischemic myopathy evidenced by smaller muscle masses, reduced contractile function, histopathology, altered vasculogenic signaling, and lower mitochondrial respiratory function. CONCLUSIONS These findings establish AHR activation in muscle as a pivotal regulator of the ischemic limb pathology in CKD. Further, the totality of the results provides support for testing of clinical interventions that diminish AHR signaling in these conditions.
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Affiliation(s)
- Nicholas Balestrieri
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Victoria Palzkill
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Caroline Pass
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Jianna Tan
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Zachary R. Salyers
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Chatick Moparthy
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Ania Murillo
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Kyoungrae Kim
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Trace Thome
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Qingping Yang
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
| | - Kerri A. O’Malley
- Department of Surgery, The University of Florida, Gainesville, FL, USA
| | - Scott A. Berceli
- Department of Surgery, The University of Florida, Gainesville, FL, USA
| | - Feng Yue
- Department of Animal Sciences, The University of Florida, Gainesville, FL, USA
- Myology Institute, The University of Florida, Gainesville, FL, USA
| | | | - Leonardo F. Ferreira
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
- Center for Exercise Science, The University of Florida, Gainesville, FL, USA
- Myology Institute, The University of Florida, Gainesville, FL, USA
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology, The University of Florida, Gainesville, FL, USA
- Center for Exercise Science, The University of Florida, Gainesville, FL, USA
- Myology Institute, The University of Florida, Gainesville, FL, USA
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Dong G, Moparthy C, Thome T, Kim K, Yue F, Ryan TE. IGF-1 Therapy Improves Muscle Size and Function in Experimental Peripheral Arterial Disease. JACC Basic Transl Sci 2023; 8:702-719. [PMID: 37426532 PMCID: PMC10322901 DOI: 10.1016/j.jacbts.2022.12.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 12/16/2022] [Accepted: 12/19/2022] [Indexed: 03/11/2023]
Abstract
Lower-extremity peripheral arterial disease (PAD) has increased in prevalence, yet therapeutic development has remained stagnant. Skeletal muscle health and function has been strongly linked to quality of life and medical outcomes in patients with PAD. Using a rodent model of PAD, this study demonstrates that treatment of the ischemic limb with insulin-like growth factor (IGF)-1 significantly increases muscle size and strength without improving limb hemodynamics. Interestingly, the effect size of IGF1 therapy was larger in female mice than in male mice, highlighting the need to carefully examine sex-dependent effects in experimental PAD therapies.
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Affiliation(s)
- Gengfu Dong
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - Chatick Moparthy
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - Trace Thome
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - Kyoungrae Kim
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
| | - Feng Yue
- Department of Animal Sciences, University of Florida, Gainesville, Florida, USA
- Myology Institute, University of Florida, Gainesville, Florida, USA
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA
- Center for Exercise Science, University of Florida, Gainesville, Florida, USA
- Myology Institute, University of Florida, Gainesville, Florida, USA
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Balestrieri N, Palzkill V, Pass C, Tan J, Salyers ZR, Moparthy C, Murillo A, Kim K, Thome T, Yang Q, O'Malley KA, Berceli SA, Yue F, Scali ST, Ferreira LF, Ryan TE. Chronic activation of the aryl hydrocarbon receptor in muscle exacerbates ischemic pathology in chronic kidney disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.16.541060. [PMID: 37292677 PMCID: PMC10245783 DOI: 10.1101/2023.05.16.541060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Chronic kidney disease (CKD) accelerates the development of atherosclerosis, decreases muscle function, and increases the risk of amputation or death in patients with peripheral artery disease (PAD). However, the cellular and physiological mechanisms underlying this pathobiology are ill-defined. Recent work has indicated that tryptophan-derived uremic toxins, many of which are ligands for the aryl hydrocarbon receptor (AHR), are associated with adverse limb outcomes in PAD. We hypothesized that chronic AHR activation, driven by the accumulation of tryptophan-derived uremic metabolites, may mediate the myopathic condition in the presence of CKD and PAD. Both PAD patients with CKD and mice with CKD subjected to femoral artery ligation (FAL) displayed significantly higher mRNA expression of classical AHR-dependent genes ( Cyp1a1 , Cyp1b1 , and Aldh3a1 ) when compared to either muscle from the PAD condition with normal renal function ( P <0.05 for all three genes) or non-ischemic controls. Skeletal-muscle-specific AHR deletion in mice (AHR mKO ) significantly improved limb muscle perfusion recovery and arteriogenesis, preserved vasculogenic paracrine signaling from myofibers, increased muscle mass and contractile function, as well as enhanced mitochondrial oxidative phosphorylation and respiratory capacity in an experimental model of PAD/CKD. Moreover, viral-mediated skeletal muscle-specific expression of a constitutively active AHR in mice with normal kidney function exacerbated the ischemic myopathy evidenced by smaller muscle masses, reduced contractile function, histopathology, altered vasculogenic signaling, and lower mitochondrial respiratory function. These findings establish chronic AHR activation in muscle as a pivotal regulator of the ischemic limb pathology in PAD. Further, the totality of the results provide support for testing of clinical interventions that diminish AHR signaling in these conditions.
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Salyers ZR, Mariani V, Balestrieri N, Kumar RA, Vugman NA, Thome T, Villani KR, Berceli SA, Scali ST, Vasilakos G, Ryan TE. S100A8 and S100A9 are elevated in chronically threatened ischemic limb muscle and induce ischemic mitochondrial pathology in mice. JVS Vasc Sci 2022; 3:232-245. [PMID: 35647565 PMCID: PMC9133641 DOI: 10.1016/j.jvssci.2022.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 03/22/2022] [Indexed: 11/19/2022] Open
Abstract
Objective The objective of the present study was to determine whether elevated levels of S100A8 and S100A9 (S100A8/A9) alarmins contribute to ischemic limb pathology. Methods Gastrocnemius muscle was collected from control patients without peripheral arterial disease (PAD; n = 14) and patients with chronic limb threatening limb ischemia (CLTI; n = 14). Mitochondrial function was assessed in permeabilized muscle fibers, and RNA and protein analyses were used to quantify the S100A8/A9 levels. Additionally, a mouse model of hindlimb ischemia with and without exogenous delivery of S100A8/A9 was used. Results Compared with the non-PAD control muscles, CLTI muscles displayed significant increases in the abundance of S100A8 and S100A9 at both mRNA and protein levels (P < .01). The CLTI muscles also displayed significant impairment in mitochondrial oxidative phosphorylation and increased mitochondrial hydrogen peroxide production compared with the non-PAD controls. The S100A8/A9 levels correlated significantly with the degree of muscle mitochondrial dysfunction (P < .05 for all). C57BL6J mice treated with recombinant S100A8/A9 displayed impaired perfusion recovery and muscle mitochondrial impairment compared with the placebo-treated mice after hindlimb ischemia surgery. These mitochondrial deficits observed after S100A8/A9 treatment were confirmed in the muscle cell culture system under normoxic conditions. Conclusions The S100A8/A9 levels were increased in CLTI limb muscle specimens compared with the non-PAD control muscle specimens, and the level of accumulation was associated with muscle mitochondrial impairment. Elevated S100A8/A9 levels in mice subjected to hindlimb ischemia impaired perfusion recovery and mitochondrial function. Together, these findings suggest that the inflammatory mediators S100A8/A9 might be directly involved in ischemic limb pathology. Despite improvements in the surgical management of chronic limb threatening limb ischemia (CLTI), the rates of major adverse limb events have remained high. Skeletal muscle has emerged as a strong predictor of outcomes in peripheral arterial disease (PAD)/CLTI; however, a complete understanding of muscle pathology in CLTI is lacking. This study identified elevated S100A8 and S100A9 alarmin proteins as a characteristic of CLTI muscle specimens and that the S100A8/A9 levels are associated with the degree of mitochondrial impairment in patient limb muscle specimens. Using a mouse model of PAD, treatment with S100A8/A9 exacerbated ischemic limb pathology, including impaired limb perfusion recovery and muscle mitochondrial impairment. Taken together, these findings connect the inflammatory milieu in the CLTI limb to exacerbated limb muscle outcomes via mitochondrial alterations.
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Affiliation(s)
- Zachary R. Salyers
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Vinicius Mariani
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Nicholas Balestrieri
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Ravi A. Kumar
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Nicholas A. Vugman
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Trace Thome
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Katelyn R. Villani
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Scott A. Berceli
- Department of Surgery, University of Florida, Gainesville, FL
- Malcom Randall Veterans Affairs Medical Center, Gainesville, FL
| | - Salvatore T. Scali
- Department of Surgery, University of Florida, Gainesville, FL
- Malcom Randall Veterans Affairs Medical Center, Gainesville, FL
| | - Georgios Vasilakos
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
- Center for Exercise Science, University of Florida, Gainesville, FL
- Myology Institute, University of Florida, Gainesville, FL
- Correspondence: Terence E. Ryan, PhD, Department of Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd, Gainesville, FL 32611
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