SS-31 does not prevent or reduce muscle atrophy 7 days after a 65 kdyne contusion spinal cord injury in young male mice.

Graham ZA, DeBerry JJ, Cardozo CP, Bamman MM

Physiological reports1 May 2022Cited by 10 (Europe PMC)

PMID35611788PMCIDPMC9131615DOI10.14814/phy2.15266PepBankPUB-35611788

Summary

Spinal cord injury (SCI) leads to major reductions in function, independent living, and quality of life. Disuse and paralysis from SCI leads to rapid muscle atrophy, with chronic muscle loss likely playing a role in the development of the secondary metabolic disorders often seen in those with SCI. Muscle disuse is associated with mitochondrial dysfunction. Previous evidence has suggested targeting the mitochondria with the tetrapeptide SS-31 is beneficial for muscle health in preclinical models that lead to mitochondrial dysfunction, such as cast immobilization or burn injury. We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31. Hindlimb muscle mass and muscle bundle respiration were measured at 7 days post-SCI and molecular targets were investigated using immunoblotting, RT-qPCR, and metabolomics. SS-31 did not preserve body mass or hindlimb muscle mass 7 days post-SCI. SS-31 had no effect on soleus or plantaris muscle bundle respiration. SCI was associated with elevated levels of protein carbonylation, led to reduced protein expression of activated DRP1 and reductions in markers of mitochondrial fusion. SS-31 administration did result in reduced total DRP1 expression, as well as greater expression of inhibited DRP1. Gene expression of proinflammatory cytokines and their receptors were largely stable across groups, although SS-31 treatment led to greater mRNA expression of IL1B, TNF, and TNFRSF12A. In summation, SS-31 was not an efficacious treatment acutely after a moderate thoracic contusion SCI in young male mice.

CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study7

7 results from studies that gave the peptide. No result from this study comes from people.

01AnimalAnimal study (in vivo)Mechanism
In young male mice with thoracic contusion SCI, gene expression of other proinflammatory cytokines and their receptors was largely stable across groups.
In plain wordsIn mice with spinal cord injury, most inflammation-related gene activity in muscle was similar across groups, SS‑31 treatment included.
Peptide
Elamipretide (SS-31)
Outcome
No significant changeOther proinflammatory cytokine and receptor gene expression
Study
mousen = 26
thoracic contusion spinal cord injury
Comparator
Sham and untreated SCI groups
Outcome group
Inflammation markers · Immune and inflammation
Studied dose
5.0 mg/kg dailyAs given in this study (mouse).
Source sentences
Summary
Gene expression of proinflammatory cytokines and their receptors were largely stable across groups
1 context sentence(design, population, supporting numbers)
Summary · context
We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31.
Show in the study text Report a problemFND-3561178807
02AnimalAnimal study (in vivo)Efficacy outcome
In young male mice with thoracic contusion SCI, SS‑31 did not preserve body mass.
In plain wordsIn mice with spinal cord injury, SS‑31 did not prevent loss of body mass.
Peptide
Elamipretide (SS-31)
Outcome
No significant changeBody mass at 7 days post-SCI
Study
mousen = 18
thoracic contusion spinal cord injury
Comparator
Untreated SCI
Outcome group
Body weight · Metabolic and weight
Studied dose
5.0 mg/kg dailyAs given in this study (mouse).
Source sentences
Summary
SS-31 did not preserve body mass or hindlimb muscle mass 7 days post-SCI.
1 context sentence(design, population, supporting numbers)
Summary · context
We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31.
Show in the study text Report a problemFND-3561178801
03AnimalAnimal study (in vivo)Efficacy outcome
In young male mice with thoracic contusion SCI, SS‑31 did not preserve hindlimb muscle mass.
In plain wordsIn mice with spinal cord injury, SS‑31 did not prevent loss of hindlimb muscle.
Peptide
Elamipretide (SS-31)
Outcome
No significant changeHindlimb muscle mass at 7 days post-SCI
Study
mousen = 18
thoracic contusion spinal cord injury
Comparator
Untreated SCI
Outcome group
Muscle injury and repair · Musculoskeletal
Studied dose
5.0 mg/kg dailyAs given in this study (mouse).
Source sentences
Summary
SS-31 did not preserve body mass or hindlimb muscle mass 7 days post-SCI
1 context sentence(design, population, supporting numbers)
Summary · context
We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31.
Show in the study text Report a problemFND-3561178802
04AnimalAnimal study (in vivo)Efficacy outcome
In young male mice with thoracic contusion SCI, SS‑31 had no effect on soleus or plantaris muscle bundle respiration.
In plain wordsIn mice with spinal cord injury, SS‑31 did not change muscle respiration.
Peptide
Elamipretide (SS-31)
Outcome
No significant changeSoleus and plantaris muscle bundle respiration
Study
mousen = 18
thoracic contusion spinal cord injury
Comparator
Untreated SCI
Outcome group
Mitochondrial function · Musculoskeletal
Studied dose
5.0 mg/kg dailyAs given in this study (mouse).
Source sentences
Summary
SS-31 had no effect on soleus or plantaris muscle bundle respiration.
1 context sentence(design, population, supporting numbers)
Summary · context
We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31.
Show in the study text Report a problemFND-3561178803
05AnimalAnimal study (in vivo)Mechanism
In young male mice with thoracic contusion SCI, SS‑31 reduced total DRP1 expression in muscle.
In plain wordsIn mice with spinal cord injury, SS‑31 lowered the level of a mitochondrial protein, DRP1, in muscle.
Peptide
Elamipretide (SS-31)
Outcome
DecreaseTotal DRP1 expression
Study
mousen = 18
thoracic contusion spinal cord injury
Comparator
Untreated SCI
Outcome group
Mitochondrial function · Musculoskeletal
Studied dose
5.0 mg/kg dailyAs given in this study (mouse).
Source sentences
Summary
SS-31 administration did result in reduced total DRP1 expression, as well as greater expression of inhibited DRP1.
1 context sentence(design, population, supporting numbers)
Summary · context
We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31.
Show in the study text Report a problemFND-3561178804
06AnimalAnimal study (in vivo)Mechanism
In young male mice with thoracic contusion SCI, SS‑31 increased expression of inhibited DRP1 in muscle.
In plain wordsIn mice with spinal cord injury, SS‑31 raised the level of the inhibited form of the protein DRP1 in muscle.
Peptide
Elamipretide (SS-31)
Outcome
IncreaseInhibited DRP1 expression
Study
mousen = 18
thoracic contusion spinal cord injury
Comparator
Untreated SCI
Outcome group
Mitochondrial function · Musculoskeletal
Studied dose
5.0 mg/kg dailyAs given in this study (mouse).
Source sentences
Summary
as well as greater expression of inhibited DRP1.
1 context sentence(design, population, supporting numbers)
Summary · context
We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31.
Show in the study text Report a problemFND-3561178805
07AnimalAnimal study (in vivo)Mechanism
In young male mice with thoracic contusion SCI, SS‑31 treatment led to greater mRNA expression of IL1B, TNF and TNFRSF12A in muscle.
In plain wordsIn mice with spinal cord injury, SS‑31 raised muscle gene activity for three inflammation-related genes.
Peptide
Elamipretide (SS-31)
Outcome
IncreasemRNA expression of IL1B, TNF and TNFRSF12A
Study
mousen = 18
thoracic contusion spinal cord injury
Comparator
Untreated SCI
Outcome group
Inflammation markers · Immune and inflammation
Studied dose
5.0 mg/kg dailyAs given in this study (mouse).
Source sentences
Summary
SS-31 treatment led to greater mRNA expression of IL1B, TNF, and TNFRSF12A.
1 context sentence(design, population, supporting numbers)
Summary · context
We gave young male mice a sham (n = 8) or 65 kdyne thoracic contusion SCI with (n = 9) or without (n = 9) daily administration of 5.0 mg/kg SS-31.
Show in the study text Report a problemFND-3561178806

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
10 Oct 2026, 08:19 UTC
Study results updated
Version 1
9 Oct 2026, 02:47 UTC
First added · source update from Europe PMC

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