Mitochondrial Dysfunctions Driving Insulin Resistance (MITO-DYS-IR)

Mitochondrial Derangements Driving Muscle Insulin Resistance in Humans

The overarching aim of this observational study is to characterize muscle mitochondrial defects in individuals harboring pathogenic mitochondrial DNA (mtDNA) mutations associated with an insulin-resistant phenotype.

In a case-control design, individuals with pathogenic mtDNA mutations will be compared to controls matched for sex, age, and physical activity level. Participants will attend a screening visit and two experimental trials including:

• An oral glucose tolerance test
• A hyperinsulinemic-euglycemic clamp combined with measurements of femoral artery blood flow and arteriovenous difference of glucose
• Muscle biopsy samples

Study Overview

• Status: Recruiting
• Conditions: Mitochondrial Diseases; Mitochondrial Myopathies; Mitochondrial Disorders

Detailed Description

Background: Peripheral insulin resistance is a major risk factor for metabolic diseases such as type 2 diabetes. Skeletal muscle accounts for the majority of insulin-stimulated glucose disposal, hence restoring insulin action in skeletal muscle is key in the prevention of type 2 diabetes. Mitochondrial dysfunction is implicated in the etiology of muscle insulin resistance. Also, as mitochondrial function is determined by its proteome quantity and quality, alterations in the muscle mitochondrial proteome may play a critical role in the pathophysiology of insulin resistance. However, insulin resistance is multifactorial in nature and whether mitochondrial derangements are a cause or a consequence of impaired insulin action is unclear. In recent years, the study of humans with genetic mutations has shown enormous potential to establish the mechanistic link between two physiological variables; indeed, if the mutation has a functional impact on one of those variables, then the direction of causality can be readily ascribed. Mitochondrial myopathies are genetic disorders of the mitochondrial respiratory chain affecting predominantly skeletal muscle. Mitochondrial myopathies are caused by pathogenic mutations in either nuclear or mitochondrial DNA (mtDNA), which ultimately lead to mitochondrial dysfunction. Although the prevalence of mtDNA mutations is just 1 in 5,000, the study of patients with mtDNA defects has the potential to provide unique information on the pathogenic role of mitochondrial derangements that is disproportionate to the rarity of affected individuals. The m.3243A>G mutation in the MT-TL1 gene encoding the mitochondrial leucyl-tRNA 1 gene is the most common mutation leading to mitochondrial myopathy in humans. The m.3243A>G mutation is associated with impaired glucose tolerance and insulin resistance in skeletal muscle. Most importantly, insulin resistance precedes impairments of β-cell function in carriers of the m.3243A>G mutation, making these patients an ideal human model to study the causative nexus between muscle mitochondrial dysfunction and insulin resistance. Thus, a comprehensive characterization of mitochondrial functional defects and the associated proteome alterations in patients harboring a mtDNA mutation associated with an insulin-resistant phenotype may elucidate the causal nexus between mitochondrial derangements and insulin resistance. Also, as mitochondrial dysfunction exhibits many faces (e.g. reduced oxygen consumption rate, impaired ATP synthesis, overproduction of reactive oxygen species, altered membrane potential), such an approach may clarify which features of mitochondrial dysfunction play a prominent role in the pathogenesis of insulin resistance.

Objective: To characterize muscle mitochondrial defects in individuals harboring pathogenic mitochondrial DNA (mtDNA) mutations associated with an insulin-resistant phenotype.

Study design: Case-control study in individuals with pathogenic mtDNA mutations (n=15) and healthy controls (n=15) matched for sex, age, and physical activity level.

Endpoint: Differences between individuals with pathogenic mtDNA mutations and controls.

• Study Type: Observational
• Enrollment (Estimated): 30

Contacts and Locations

• Study Contact: Name: Matteo Fiorenza, Ph.D.; Phone Number: +4535458748; Email: matteo.fiorenza@regionh.dk
• Study Contact Backup: Name: Tue Leth Nielsen, MD; Phone Number: +4535458748; Email: tue.leth.nielsen.01@regionh.dk

Study Locations

• Denmark
  • Copenhagen, Denmark, 2100
    • Recruiting
    • Rigshospitalet
    • Contact: Tue Leth Nielsen, MD; Phone Number: +4535458748; Email: tue.leth.nielsen.01@regionh.dk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Individuals with mitochondrial myopathy due to pathogenic mtDNA mutations are identified and recruited from the Copenhagen Neuromuscular Center or the Department of Clinical Genetics (Rigshospitalet).

Control volunteers are recruited via recruitment announcements in Denmark.

Description

Eligibility criteria for individuals with pathogenic mtDNA mutations

Inclusion criteria:

• Known m.3243A>G mutation in the MT-TL1 gene encoding the mitochondrial leucyl-tRNA 1 gene
• Other known mtDNA point mutations

Exclusion criteria:

• Use of antiarrhythmic medications or other medications which, in the opinion of the investigators, have the potential to affect outcome measures.
• Diagnosed severe heart disease, dysregulated thyroid gland conditions, or other dysregulated endocrinopathies, or other conditions which, in the opinion of the investigators, have the potential to affect outcome measures.
• Pregnancy

Eligibility criteria for controls

Exclusion criteria:

• Current and regular use of antidiabetic medications or other medications which, in the opinion of the investigators, have the potential to affect outcome measures.
• Diagnosed heart disease, symptomatic asthma, liver cirrhosis or -failure, chronic kidney disease, dysregulated thyroid gland conditions or other dysregulated endocrinopathies, or other conditions which, in the opinion of the investigators, have the potential to affect outcome measures
• Daily use of tobacco products
• Excessive alcohol consumption
• Pregnancy

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Mitochondrial myopathy; Individuals with pathogenic mtDNA mutations
Control; Individuals without mtDNA mutations

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle mitochondrial respiration	Mitochondrial O2 flux is measured by high-resolution respirometry in permeabilized fibers from muscle biopsy samples	Baseline
Muscle mitochondrial reactive oxygen species (ROS) production	Mitochondrial H2O2 emission rates are measured by high-resolution fluorometry in permeabilized fibers from muscle biopsy samples	Baseline
Muscle mitochondrial proteome	Mitochondrial proteome signatures are determined by mass spectrometry-based proteomics in muscle biopsy samples	Baseline
Skeletal muscle insulin sensitivity	Insulin-stimulated muscle glucose uptake is determined by the hyperinsulinemic-euglycemic clamp method integrated with measurements of femoral artery blood flow and arteriovenous difference of glucose	90-150 minutes after initiation of the hyperinsulinemic euglycemic clamp
Whole-body insulin sensitivity	Whole-body insulin sensitivity is determined by the hyperinsulinemic-euglycemic clamp method	90-150 minutes after initiation of the hyperinsulinemic euglycemic clamp

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle mtDNA heteroplasmy	mtDNA mutation load is measured in muscle biopsy samples from the patients with mitochondrial myopathy	Baseline
Muscle integrated stress response genes	mRNA content of genes governing the integrated stress response pathway is measured by Real-Time PCR in muscle biopsy samples.	Baseline
Glucose tolerance	Glucose tolerance is determined by the plasma glucose response curve measured during an oral glucose tolerance test	0-180 minutes after ingestion of an oral glucose solution
Beta cell function	Beta cell function is determined by measurements of plasma insulin and insulin C-peptide during an oral glucose tolerance test	0-180 minutes after ingestion of an oral glucose solution
Muscle insulin signaling	Insulin-mediated changes in the abundance of (phosphorylated) proteins modulating insulin action are measured by immunoblotting in muscle and fat biopsy samples	Before (baseline) and 0-150 minutes after initiation of a hyperinsulinemic-euglycemic clamp
Muscle integrated stress response signaling proteins	Abundance of (phosphorylated) proteins modulating the integrated stress response pathway is measured by immunoblotting in muscle biopsy samples.	Baseline
Muscle release of FGF21 and GDF15	Skeletal muscle production of FGF21 and GDF15 is determined by measurements of femoral artery blood flow and arteriovenous difference of plasma FGF21 and GDF15	Before (baseline) and 0-150 minutes after initiation of a hyperinsulinemic-euglycemic clamp

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cardiorespiratory fitness	Pulmonary maximal oxygen uptake (VO2max) is determined during an incremental exercise test to exhaustion	Baseline
Self-reported physical activity	Self-reported physical activity is measured by the International Physical Activity Questionnaire - Short Form (IPAQ-SF)	Baseline
Leg muscle mass	Leg muscle mass is determined by dual-energy X-ray absorptiometry	Baseline
Body composition	Whole-body fat free mass and fat mass are determined by dual-energy X-ray absorptiometry	Baseline
Physical activity level	Physical activity is measured by wrist-worn accelerometers	Baseline

Collaborators and Investigators

• Sponsor: Rigshospitalet, Denmark
• Collaborators: University of Copenhagen
• Investigators: Principal Investigator: Matteo Fiorenza, Ph.D., Rigshospitalet, Denmark; Principal Investigator: John Vissing, MD, Rigshospitalet, Denmark

Publications and helpful links

General Publications

• DeFronzo RA, Ferrannini E. Insulin resistance. A multifaceted syndrome responsible for NIDDM, obesity, hypertension, dyslipidemia, and atherosclerotic cardiovascular disease. Diabetes Care. 1991 Mar;14(3):173-94. doi: 10.2337/diacare.14.3.173.
• Hesselink MK, Schrauwen-Hinderling V, Schrauwen P. Skeletal muscle mitochondria as a target to prevent or treat type 2 diabetes mellitus. Nat Rev Endocrinol. 2016 Nov;12(11):633-645. doi: 10.1038/nrendo.2016.104. Epub 2016 Jul 22.
• Gorman GS, Schaefer AM, Ng Y, Gomez N, Blakely EL, Alston CL, Feeney C, Horvath R, Yu-Wai-Man P, Chinnery PF, Taylor RW, Turnbull DM, McFarland R. Prevalence of nuclear and mitochondrial DNA mutations related to adult mitochondrial disease. Ann Neurol. 2015 May;77(5):753-9. doi: 10.1002/ana.24362. Epub 2015 Mar 28.
• DeFronzo RA, Simonson D, Ferrannini E. Hepatic and peripheral insulin resistance: a common feature of type 2 (non-insulin-dependent) and type 1 (insulin-dependent) diabetes mellitus. Diabetologia. 1982 Oct;23(4):313-9. doi: 10.1007/BF00253736.
• O'Rahilly S. "Treasure Your Exceptions"-Studying Human Extreme Phenotypes to Illuminate Metabolic Health and Disease: The 2019 Banting Medal for Scientific Achievement Lecture. Diabetes. 2021 Jan;70(1):29-38. doi: 10.2337/dbi19-0037.
• Saleheen D, Natarajan P, Armean IM, Zhao W, Rasheed A, Khetarpal SA, Won HH, Karczewski KJ, O'Donnell-Luria AH, Samocha KE, Weisburd B, Gupta N, Zaidi M, Samuel M, Imran A, Abbas S, Majeed F, Ishaq M, Akhtar S, Trindade K, Mucksavage M, Qamar N, Zaman KS, Yaqoob Z, Saghir T, Rizvi SNH, Memon A, Hayyat Mallick N, Ishaq M, Rasheed SZ, Memon FU, Mahmood K, Ahmed N, Do R, Krauss RM, MacArthur DG, Gabriel S, Lander ES, Daly MJ, Frossard P, Danesh J, Rader DJ, Kathiresan S. Human knockouts and phenotypic analysis in a cohort with a high rate of consanguinity. Nature. 2017 Apr 12;544(7649):235-239. doi: 10.1038/nature22034.
• DeFronzo RA, Gunnarsson R, Bjorkman O, Olsson M, Wahren J. Effects of insulin on peripheral and splanchnic glucose metabolism in noninsulin-dependent (type II) diabetes mellitus. J Clin Invest. 1985 Jul;76(1):149-55. doi: 10.1172/JCI111938.
• Diaz-Vegas A, Sanchez-Aguilera P, Krycer JR, Morales PE, Monsalves-Alvarez M, Cifuentes M, Rothermel BA, Lavandero S. Is Mitochondrial Dysfunction a Common Root of Noncommunicable Chronic Diseases? Endocr Rev. 2020 Jun 1;41(3):bnaa005. doi: 10.1210/endrev/bnaa005.
• Parish R, Petersen KF. Mitochondrial dysfunction and type 2 diabetes. Curr Diab Rep. 2005 Jun;5(3):177-83. doi: 10.1007/s11892-005-0006-3.
• Zabielski P, Lanza IR, Gopala S, Heppelmann CJ, Bergen HR 3rd, Dasari S, Nair KS. Altered Skeletal Muscle Mitochondrial Proteome As the Basis of Disruption of Mitochondrial Function in Diabetic Mice. Diabetes. 2016 Mar;65(3):561-73. doi: 10.2337/db15-0823. Epub 2015 Dec 30.
• Petersen MC, Shulman GI. Mechanisms of Insulin Action and Insulin Resistance. Physiol Rev. 2018 Oct 1;98(4):2133-2223. doi: 10.1152/physrev.00063.2017.
• DiMauro S. Mitochondrial myopathies. Curr Opin Rheumatol. 2006 Nov;18(6):636-41. doi: 10.1097/01.bor.0000245729.17759.f2.
• Elliott HR, Samuels DC, Eden JA, Relton CL, Chinnery PF. Pathogenic mitochondrial DNA mutations are common in the general population. Am J Hum Genet. 2008 Aug;83(2):254-60. doi: 10.1016/j.ajhg.2008.07.004.
• Frederiksen AL, Jeppesen TD, Vissing J, Schwartz M, Kyvik KO, Schmitz O, Poulsen PL, Andersen PH. High prevalence of impaired glucose homeostasis and myopathy in asymptomatic and oligosymptomatic 3243A>G mitochondrial DNA mutation-positive subjects. J Clin Endocrinol Metab. 2009 Aug;94(8):2872-9. doi: 10.1210/jc.2009-0235. Epub 2009 May 26.
• Lindroos MM, Majamaa K, Tura A, Mari A, Kalliokoski KK, Taittonen MT, Iozzo P, Nuutila P. m.3243A>G mutation in mitochondrial DNA leads to decreased insulin sensitivity in skeletal muscle and to progressive beta-cell dysfunction. Diabetes. 2009 Mar;58(3):543-9. doi: 10.2337/db08-0981. Epub 2008 Dec 10.

Study record dates

Study Major Dates

• Study Start (Actual): October 20, 2023
• Primary Completion (Estimated): December 1, 2025
• Study Completion (Estimated): December 1, 2025

Study Registration Dates

• First Submitted: September 29, 2023
• First Submitted That Met QC Criteria: October 6, 2023
• First Posted (Actual): October 12, 2023

Study Record Updates

• Last Update Posted (Actual): November 18, 2023
• Last Update Submitted That Met QC Criteria: November 17, 2023
• Last Verified: November 1, 2023

More Information

Terms related to this study

• Keywords: Insulin resistance; Mitochondrial disease; Muscle metabolism
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Nervous System Diseases; Musculoskeletal Diseases; Muscular Diseases; Neuromuscular Diseases; Hyperinsulinism; Mitochondrial Diseases; Insulin Resistance; Mitochondrial Myopathies
• Other Study ID Numbers: MITO-DYS-IR

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No