HGH Fragment 176-191
AOD variant
Synthetic fragment of human growth hormone (amino acids 176–191). Not FDA-approved; investigational.
Endogenous mitochondrial-derived peptide. Not FDA-approved; evidence is largely preclinical.
MOTS-c (mitochondrial open reading frame of the twelve S rRNA type-c) is a 16-amino-acid peptide encoded within the mitochondrial DNA — specifically within the 12S ribosomal RNA gene. It is one of the family of “mitochondrial-derived peptides” (MDPs) discovered over the past decade.
MOTS-c was first characterized in 2015 by Pinchas Cohen’s laboratory at USC. The discovery added to a growing recognition that mitochondria produce signaling peptides. Other mitochondrial-derived peptides include humanin and the SHLP family of peptides.
MOTS-c is not FDA-approved for any use in the United States. Human research is limited and at an early stage.
Proposed mechanisms come from laboratory and animal research:
MOTS-c research is mostly preclinical:
Metabolic findings in animals: in rodent studies, MOTS-c was associated with changes in insulin sensitivity and glucose tolerance.
Aging models: in aged mice, MOTS-c administration was associated with changes in metabolic measures.
Diabetic models: reductions in fasting glucose were reported in diabetic animal models.
Mitochondrial dysfunction: protective effects were reported in some animal and cell models of mitochondrial stress.
Human research: small early-phase studies of MOTS-c or related analogs have been published; benefit in people has not been established.
Well-controlled human trials establishing the effectiveness and safety of MOTS-c are lacking.
Human safety has not been established in well-controlled trials, and long-term effects are unknown. Products sold outside regulated channels (for example, as “research peptides”) may vary in purity, dose, and sterility.
Caution areas:
MOTS-c has not accumulated a meaningful clinical evidence base. Long-term safety and any effects in people with multi-year exposure are not characterized. How MOTS-c compares with established metabolic therapies has not been studied. Whether MOTS-c has any effect in healthy adults or in people with metabolic disease, beyond what exercise, diet, and sleep provide, is an open question.
AOD variant
Synthetic fragment of human growth hormone (amino acids 176–191). Not FDA-approved; investigational.
Growth hormone fragment 177–191
Synthetic fragment of human growth hormone (amino acids 177–191). Not FDA-approved; investigational.