SS-31

What Is SS-31 / Elamipretide?

Elamipretide (SS-31) is a synthetic, mitochondrial-targeted tetrapeptide. It consists of four amino acids and can easily reach the inner mitochondrial membrane. SS-31 binds to cardiolipin, a key phospholipid that maintains mitochondrial structure and function. This interaction stabilizes the membrane, reduces reactive oxygen species (ROS), and protects mitochondria, enhancing cellular energy production. In cell and preclinical research, SS-31 is used to investigate mitochondrial dysfunction, activate protective cellular responses, and study oxidative stress pathways. Its small size and positive charge make it an effective tool for studying mitochondrial stability under stress.

Molecular Structure and Composition

SS-31 (Elamipretide) is a synthetic tetrapeptide composed of D-arginine, 2,6-dimethyltyrosine (Dmt), lysine, and phenylalanine, with an amidated C-terminus. Its sequence is D-Arg-Dmt-Lys-Phe-NH2. The incorporation of a D-amino acid and methylated tyrosine increases resistance to enzymatic degradation and enhances mitochondrial uptake in laboratory studies. Molecular formula: C32H49N9O5 Molecular weight: 639.8 Da Its small size and positive charge allow efficient accumulation in the inner mitochondrial membrane, making SS-31 an excellent research tool for studying mitochondrial structure and function.

Mechanism of Action

SS-31 rapidly enters cells and accumulates in the inner mitochondrial membrane due to its small size and positive charge. It binds to cardiolipin, a phospholipid that stabilizes mitochondrial cristae and supports the electron transport chain. This binding enhances electron flow, reduces ROS generation, and increases ATP production. In laboratory models, these effects protect mitochondria from oxidative damage, maintain energy production, and help cells endure stress. SS-31 is used to study mitochondrial stability, energy metabolism, and cellular responses to oxidative stress.

Research Applications

SS-31 is employed to study mitochondrial defense, cellular responses to oxidative stress, and energy metabolism. It helps researchers monitor mitochondrial activity and assess cellular health in experimental models.

Mitochondrial Function Studies

In cell-based models, SS-31 is used to measure mitochondrial structure and function, including ATP production, electron transport, and cristae stability. These studies reveal the effects of targeted peptides on mitochondrial energy in normal and stressed conditions.

Oxidative Stress and Antioxidant Research

SS-31 helps investigate cellular defense mechanisms and oxidative damage. Experiments demonstrate reduced ROS, diminished lipid peroxidation, and preservation of antioxidant systems, clarifying mitochondrial protective mechanisms.

Cardioprotective and Neuroprotective Models

SS-31 is used in heart and brain cell models to assess protection against injury. Experiments induce ischemia or toxin exposure, then measure mitochondrial membrane stability, reduced cell death, and tissue recovery.

Preclinical Research Applications

In animal studies, SS-31 is applied to examine mitochondrial restoration following stress or organ dysfunction. Research focuses on tissue protection, inhibition of inflammatory signaling, and maintenance of functional integrity under controlled preclinical conditions.

Product Form and Specification

SS-31 (Elamipretide) is supplied as a white lyophilized powder in sterile glass vials. Each vial contains 5 mg of peptide with ≥98% purity. The formulation does not contain fillers, stabilizers, or preservatives unless otherwise specified, and is designed to provide consistent results in laboratory and preclinical research.

Intended Research Use

SS-31 is for laboratory and scientific research only. It is used in vitro (cell culture) and approved preclinical animal studies. Researchers utilize it to investigate mitochondrial protection, oxidative stress adaptation, energy production pathways, and cellular homeostasis. All research involving animals or humans must comply with institutional, ethical, and regulatory guidelines.

Storage and Handling

Store lyophilized powder at -20°C in a light- and moisture-free environment for long-term stability. Minimize air exposure. Reconstitute with sterile water, saline, or bacteriostatic water as needed, and handle gently. Reconstituted solutions can be stored at 2–8°C short-term (typically 14–30 days). For longer storage, aliquot and freeze at ≤-20°C, avoiding repeated freeze-thaw cycles. Always practice aseptic technique: wear gloves, work in a clean environment, and use sterile instruments to prevent contamination.

Regulatory and Safety Disclaimer

SS-31 / Elamipretide is intended solely for laboratory and scientific research. It has not been approved by the FDA or any other regulatory authority for human or animal use. Its safety, efficacy, or suitability is not guaranteed outside research settings. Researchers must follow institutional safety protocols, ethical standards, and applicable legislation. Always consult material safety data sheets, use appropriate protective clothing, and dispose of waste properly. The supplier is not responsible for misuse or improper handling.

References

• Mitchell, W. H., et al. (2020). The mitochondria‑targeted peptide SS‑31 binds lipid bilayers and modulates surface electrostatics as a key component of its mechanism of action. Bioenergetics & Membrane Biophysics.
• Szeto, H. H. (2019). Elamipretide (SS‑31) improves mitochondrial dysfunction, synaptic and memory impairment induced by lipopolysaccharide in mice. Journal of Neuroinflammation, 16, 230.
• Elamipretide (SS31) (2021). The effects of a mitochondrial‑targeted peptide (elamipretide/SS31) on BAX recruitment and activation during apoptosis. BMC Research Notes, 14, 198.
• Martinez, M. A., et al. (2023). The mitochondria‑targeted peptide elamipretide (SS‑31) improves mitochondrial ADP sensitivity and bioenergetic profiles in aging muscle models. Journal of Gerontology & Mitochondrial Research.