A 16-amino-acid peptide your own mitochondria make. In mouse studies it reverses age-related insulin resistance, protects against diet-induced obesity, and acts as an "exercise mimetic" — old mice given MOTS-c doubled their treadmill capacity. Not FDA-approved · added to the WADA Prohibited List in 2024. The first human therapeutic RCTs are still pending; an FDA compounding-bulks review is scheduled for July 2026.
16-AA mitochondrial-derived peptide (MDP) encoded by the MT-RNR1 (12S rRNA) gene. Activates AMPK via folate-cycle inhibition (AICAR accumulation), binds and activates casein kinase 2 (CK2), and translocates to the nucleus in metabolic stress to co-regulate ~250 NRF2/ARE-responsive genes. In HFD-fed mice, 0.5 mg/kg IP daily produced HOMA-IR −52%, fasting glucose −38%, visceral fat −27% (Lee 2015). Reynolds 2021 (Nat Commun): doubled exercise capacity in aged mice; +34% plasma rise during cycling in humans at 70% VO2max. No published human therapeutic RCT exists.
16-AA peptide MRWQEMGYIFYPRKLR (MW 2,173 Da) translated from an open reading frame within the mitochondrial 12S rRNA gene (mtDNA position 1343–1393). Mechanistically distinct from cytosolic AMPK activators: inhibits AICARFT/IMPCHase in the de novo folate cycle, allowing AICAR (an endogenous AMPK activator) to accumulate. Direct molecular target in skeletal muscle is the regulatory β-subunit of CK2; the K14Q variant (m.1382A>C polymorphism) binds CK2 ~16× more weakly and fails to stimulate glucose uptake. Translocates to the nucleus under metabolic stress (AMP/ATP ↑) where it co-regulates NRF2/ARE genes — a "retrograde" mitochondrial → nuclear signal. CAS 1627580-64-6.
The most-cited numbers across the preclinical literature and the small human pharmacology dataset — the metrics that define why MOTS-c is being investigated as a longevity, metabolic, and exercise-mimetic peptide despite the absence of approved indications.
MOTS-c is made inside your mitochondria — the energy organelles in every cell. It acts like a chemical signal from those mitochondria to the rest of the cell that says "we're stressed; act like you're exercising." It activates the same master energy sensor (AMPK) that exercise and metformin activate, plus a backup nuclear switch (NRF2) that turns on antioxidant defenses.
MOTS-c works through three mechanistically linked axes. First — it inhibits the AICAR-formyltransferase step of the folate cycle, allowing AICAR to accumulate and activate AMPK. Second — it binds the regulatory β-subunit of casein kinase 2 (CK2) in skeletal muscle, driving GLUT4 translocation and glucose uptake even without insulin. Third — under metabolic stress (elevated AMP/ATP), it translocates from cytoplasm to nucleus where it co-regulates ~250 NRF2/ARE-responsive genes. The net effect: improved glucose disposal, increased fatty-acid oxidation, induction of antioxidant defense, and a phenotype that strongly resembles aerobic exercise.
MOTS-c functions as a "retrograde" signal from mitochondrion to nucleus — a paradigm shift in mitochondrial biology where the organelle directly programs nuclear gene expression. The peptide is translated using the mitochondrial genetic code (UGA = Trp, not stop), confirmed by mass spectrometry of mitochondrial extracts. Translation occurs in mitochondrial ribosomes but accumulates cytoplasmically; nuclear translocation requires importin-α/β. The naturally occurring K14Q polymorphism (m.1382A>C, ~6% prevalence in East Asian populations) reduces CK2 binding ~16-fold and abolishes the muscle glucose-uptake response — providing the strongest causal evidence that CK2 is the operative target in skeletal muscle. Beyond glucose handling, mechanistic work has demonstrated effects on osteoclast differentiation, satellite-cell function, hippocampal LTP, and adipocyte browning.
MOTS-c is most often administered as a daily subcutaneous injection in cycled blocks (8–16 weeks on / 4–8 weeks off). No human therapeutic RCT has established a definitive regimen — every protocol below is a translation from preclinical work, the Reynolds 2021 human pharmacology study, or practice-pattern data from physician-supervised clinics. None is FDA-approved prescribing information.
Unlike an albumin-bound incretin engineered for once-weekly steady state, native MOTS-c has a short plasma residence and no validated human PK model. Every cadence on this page is therefore built around a signal-pulse logic — frequent small subcutaneous doses against a fast clearance — rather than a steady-state titration to a measured trough. The closest human reference is the engineered analog CB-4211, dosed 25 mg SC once daily for 28 days in Phase 1b; its half-life was extended over native MOTS-c but not publicly disclosed. Treat every PK value below as Grade D/P unless flagged otherwise.
| Parameter | Value | Note · grade |
|---|---|---|
| Route (primary) | Subcutaneous | Only route used in CB-4211 human Phase 1; standard in clinic. IP/IV are animal-study routes only. C |
| Half-life (t½, plasma SC) | ~30–60 min | Extrapolated from peptide-class data; no validated native-MOTS-c human PK study. D |
| Bioavailability (SC) | ~40–80% (class est.) | Not formally established for native MOTS-c; peptide-class range. D |
| Bioavailability (oral) | Very low | MDPs are proteolytically degraded; oral delivery is not viable. P |
| Cmax / Tmax (SC) | Not established | No published human PK data for the native peptide. D |
| Distribution | Skeletal muscle > liver, adipose, brain, plasma | Muscle is the primary target organ; nuclear translocation under metabolic stress. C |
| Clearance route | Presumed proteolytic / renal | Not formally characterized. D |
| Endogenous dynamics | ↑~11.9× muscle, ↑~1.6× plasma with exercise; ↓ with age | The exercise-mimetic rationale; circulating levels fall across the lifespan. C |
| Steady state | Not applicable (pulse model) | Short t½ means no meaningful accumulation; the working hypothesis is tonic receptor engagement, not a trough. D |
Architecture note: because no human PK model exists, the engine flags every native-MOTS-c PK field with validated_human_pk = false. The CB-4211 analog is the only human-anchored row in this class and is stored separately so its values are never silently inherited by the native peptide.
2 mg/day SC × 2 weeks. The lowest dose at which detectable plasma elevations have been documented in non-clinical pharmacokinetic work; chosen to verify tolerability before escalation.2 weeks if tolerated. Slower than performance / metabolic protocols because the longevity rationale favors a low-stress, sustained AMPK signal over peak effect.2 → 3 → 5 mg/day SC. 5 mg/day is the most-used practice-pattern maintenance dose for non-athletic adults. Most users stop escalation at 3–5 mg; few reach 10 mg without a specific performance or metabolic indication.3 mg/day or 5 mg/day. The lower end pairs reasonably with metformin or with a calorie-restriction regimen.8–12 weeks on · 4–8 weeks off. Cycling is preserved from the preclinical literature (Reynolds 2021 used 3×/wk intermittent dosing for maximal benefit) and is mechanistically rational — AMPK pathways exhibit tachyphylaxis with continuous activation.5 mg/day SC × 1 week. Higher starting dose than the longevity protocol because the target is acute metabolic effect on a baseline-impaired phenotype. Patients on insulin or sulfonylureas: start at 2 mg/day and reduce hypoglycemia-prone medications by 20% at initiation.1–2 weeks guided by fasting glucose, fingerstick or CGM trend, and symptoms.5 → 7.5 → 10 mg/day. 10 mg/day is the upper end of practice-pattern dosing for metabolic indications; some clinics use up to 15 mg/day in refractory severe insulin resistance but data are sparse.10 mg/day for full metabolic effect; 7.5 mg/day as a step-down maintenance once HOMA-IR has normalized.12–16 weeks on + 4-week taper to 5 mg/day + 4-week washout. Then reassess metabolic markers; resume cycle if benefit was clear and washout did not produce immediate regression.5 mg/day SC, 30–60 min pre-workout on training days; 5 mg morning on rest days.5 → 7.5 → 10 mg/day. Some protocols use a 5-day-on / 2-day-off pattern within a week to preserve AMPK responsiveness.10 mg/day pre-workout on training days; held at 5 mg/day on rest days, or paused entirely on a 2-day weekend.8 weeks on / 4–6 weeks off. Aligned with a typical hypertrophy or fat-loss training block. Reynolds 2021 intermittent-dosing benefit is preserved by within-week and across-cycle pulses.3 mg/day SC × 2 weeks. Conservative start in older or frail patients to detect any unanticipated tolerability issues at low total exposure.2 weeks. Slower escalation than performance protocols; aligned with the geriatric "start low, go slow" principle.3 → 5 mg/day. Most sarcopenia protocols do not escalate past 5 mg/day; the muscle preservation effect in animal models was observed at modest equivalent human doses, and higher doses do not appear to yield proportional additional muscle effect in preclinical work.5 mg/day as a 12-week block. The muscle-preservation effect in Zhu 2022 (sarcopenia model) developed over 8–12 weeks in aged mice and required concurrent muscle loading for full expression.5 mg/day SC × 4 weeks. The SC route is the most-characterized; CNS penetration is modest but appears sufficient at this dose range based on rodent PK / brain-tissue work.10 mg/day intranasal, divided into 5 mg per nostril, formulated with HP-β-cyclodextrin (1–2% w/v) as a permeation enhancer. IN route bypasses systemic dilution and may achieve higher CSF / olfactory bulb concentrations.5 → 10 mg/day. IN: 10 → 20 mg/day.12 weeks continuous followed by 4-week washout and reassessment. NRF2 / antioxidant effects are slow-to-develop and benefit from sustained signaling — distinct from the metabolic protocols where intermittent dosing is preferred.25 mg/day SC for 28 days in the Phase 1b NAFLD/obese cohort. This is ~2.5–5× the per-day exposure of the native-peptide metabolic protocol on this page — reflecting the analog's different potency/stability profile, not a native-MOTS-c target.Every protocol on this page resolves to one of four practice-pattern dose bands. Native MOTS-c is dosed in milligrams per day (SC, cycled), not by body weight — per-kg figures are shown only for cross-compound comparison. All native-peptide bands carry Grade C/D; the High band is the CB-4211 analog human dose and is not a native-peptide target. There is no approved label, so no band is Grade A/B for the native molecule.
| Band | Daily dose (SC) | ≈ µg/kg/day (70 kg) | Primary basis | Grade |
|---|---|---|---|---|
| Tonic / low | 1–3 mg/day | ~14–43 | Longevity & sarcopenia start; recapitulates a low-stress, sustained AMPK signal. Conservative tolerability anchor. | C |
| Standard | 5 mg/day | ~71 | Most-used practice-pattern maintenance for non-athletic adults; longevity / recomp workhorse. | C |
| Metabolic high | 7.5–10 mg/day | ~107–143 | Insulin-resistance / T2DM target for full metabolic effect; requires glucose monitoring on combination therapy. | C |
| Analog reference | 25 mg/day (CB-4211) | ~357 | CB-4211 Phase 1b human dose — engineered analog, undisclosed PK. Not a native-peptide target; shown as the class ceiling only. | B (analog) |
Some metabolic clinics report up to 15 mg/day in refractory severe insulin resistance; data are sparse and this exceeds the standard practice ceiling (Grade D). Doses are most often given once daily; some protocols pulse 5-days-on / 2-off within a week to preserve AMPK responsiveness.
| Body weight | 3 mg/day | 5 mg/day | 10 mg/day |
|---|---|---|---|
| 55 kg (121 lb) | 54.5 µg/kg | 90.9 µg/kg | 181.8 µg/kg |
| 65 kg (143 lb) | 46.2 µg/kg | 76.9 µg/kg | 153.8 µg/kg |
| 75 kg (165 lb) | 40.0 µg/kg | 66.7 µg/kg | 133.3 µg/kg |
| 85 kg (187 lb) | 35.3 µg/kg | 58.8 µg/kg | 117.6 µg/kg |
| 95 kg (209 lb) | 31.6 µg/kg | 52.6 µg/kg | 105.3 µg/kg |
| 105 kg (231 lb) | 28.6 µg/kg | 47.6 µg/kg | 95.2 µg/kg |
Practice-pattern dosing is not weight-titrated — these per-kg values exist only to compare MOTS-c against weight-dosed compounds elsewhere on the Atlas. Animal studies used 0.5–15 mg/kg IP (mouse); allometric scaling of a 5 mg/kg mouse dose gives ~0.41 mg/kg human-equivalent (≈29 mg for a 70 kg adult) — translational context only, never a dose recommendation. No formal renal/hepatic dose adjustment exists; impaired clearance argues for the low band.
These are practice-pattern rules (Grade C/D), not label-validated like an approved drug — but they are the explicit decision nodes the engine evaluates at each visit. Escalation is gated on time-at-dose and tolerability; hard stops reflect the absolute contraindications in §05. The dominant real-world limit is injection-site reaction, not systemic toxicity.
| Decision node | Rule | Rationale | Grade |
|---|---|---|---|
| Escalate | After 1–2 weeks at current dose AND tolerating well → step up one band toward target (e.g. +2–2.5 mg/day). | Short t½ means tolerability is readable within days; slower steps used for longevity/geriatric blocks. | C |
| Hold | Fasting glucose <70 mg/dL (3.9 mmol/L), or any new symptom at an escalation step → hold current dose, reassess. | AMPK activation can potentiate hypoglycemia, chiefly with insulin/secretagogues. | C |
| Hold (combination) | On insulin/sulfonylurea → reduce the hypoglycemia-prone agent 20–30% at MOTS-c initiation; monitor by CGM/fingerstick during titration. | Additive GLUT4/AMPK glucose-lowering raises hypoglycemia risk on combination. | C |
| De-escalate | Injection-site nodules >2 cm, painful, or persistent → drop one band, rotate sites more frequently. | Injection-site reaction is the dominant tolerability limit (CB-4211 Phase 1 signal). | C |
| Escalate / extend | HbA1c falls >0.5% in 4 weeks without lifestyle change → maintain or extend cycle; clear responder. | Dose-responsive metabolic improvement; reward the responding phenotype. | D |
| Discontinue (non-response) | No change in fasting glucose/HbA1c after 8 weeks at standard dose → escalate once to high band, else stop. | Non-responder (consider K14Q variant in East-Asian-ancestry non-responders). | D |
| Hard stop | New cardiac arrhythmia/palpitations, or fever >38.5 °C within 24 h of injection → stop, evaluate (infection vs reaction). | Community AE reports of tachycardia/fever; rule out injection-site infection. | D |
| Hard stop (absolute) | Active malignancy requiring treatment, or pregnancy confirmed → discontinue; do not initiate. | Theoretical oncologic AMPK exploitation; no pregnancy safety data — both are NCT07505745 exclusions. | D |
Special populations: favor the tonic/low band with slower (2-week) steps in adults >70 years. CKD (eGFR <60) or hepatic impairment (ALT/AST >2.5× ULN) → low band and closer clearance monitoring. Competitive athletes subject to WADA testing are excluded entirely regardless of titration.
Critical architecture distinction: unlike an approved drug, every biomarker below is flagged validated_for_motsc = false as a surrogate efficacy endpoint in humans — the human intervention trial (Matsuda Index, NCT07505745) is still recruiting. These markers are monitored for safety and plausible response tracking, not because any is a proven MOTS-c efficacy surrogate. The one partial exception is the liver-enzyme signal seen with the CB-4211 analog.
| Biomarker | Frequency | Threshold / action | Validated? |
|---|---|---|---|
| Fasting glucose (metabolic) | Baseline; q4 wk; ad hoc if symptomatic | <70 mg/dL → HOLD; watch on insulin/secretagogue | Not validated |
| HOMA-IR / fasting insulin | Baseline; Week 8 | Meaningful effect expected mainly if baseline HOMA-IR >3.0 | Not validated |
| HbA1c | Baseline; q4 wk (if >6.0% baseline) | >0.5% rise → reassess; >0.5% fall → responder | Not validated |
| OGTT Matsuda Index | Baseline; Week 12 | Primary efficacy endpoint of NCT07505745 — data pending ~2027 | Not validated (pending) |
| ALT / AST (hepatic) | Baseline; q4 wk | >2.5× ULN → HOLD; CB-4211 showed ALT −25% / AST −17% | Partial (analog only) |
| Lipid panel (TG/HDL/LDL) | Baseline; Week 8 | Expect modest ↓TG via AMPK/ACC; no fixed threshold | Not validated |
| eGFR / creatinine (renal) | Baseline; q4–8 wk | eGFR <60 → low band / hold | Not validated |
| Injection-site exam | Every visit | Nodule >2 cm / warm / tender → HOLD, culture | Tolerability marker |
| Resting HR / ECG | Baseline; if palpitations reported | Resting HR >100 bpm → HOLD | Not validated |
| Anti-drug antibodies | Optional baseline; Week 16 | Positive ADA + lost efficacy → STOP | Not validated (pending) |
| Serum MOTS-c | Optional baseline | Endogenous level falls with age; not an intervention-response marker | Not validated |
Architecture note: store each biomarker with a source_endpoint tag and a validated_for_motsc boolean — which is false for every native-peptide row here. This is the inverse of an approved-drug page (e.g. tirzepatide, where most markers are trial-validated) and is the single clearest structural signal that MOTS-c remains a speculative-layer molecule.
For reference only. Not medical dosing advice. Verify peptide purity, sterility, and storage. Only use product from a licensed source for any injection protocol.
MOTS-c is investigational and not approved — no formal combination clinical-trial data exist. The pairings below reflect mechanistic complementarity from the preclinical literature, observed practice patterns in physician-supervised longevity / metabolic clinics, and reasonable extrapolations from the AMPK / CK2 / NRF2 mechanism. None are FDA-validated combinations. Combination use of investigational compounds requires physician oversight.
| Component | Role | Evidence |
|---|---|---|
| MOTS-c | AICAR / AMPK · CK2 · NRF2 | Preclinical (B/C) |
| Metformin | AMP/ATP-mediated AMPK | 1L T2DM (A) |
| RT + protein | Lean mass anabolism | Evidence-based (A) |
| Component | Target | Status |
|---|---|---|
| MOTS-c | Biogenesis · CK2 | Investigational |
| SS-31 | Cardiolipin · OXPHOS | Phase 3 (B) |
| NR / NMN | NAD+ · sirtuin | Supplement (C/D) |
| Urolithin A | Mitophagy · PINK1 | FDA GRAS (C) |
| Component | Mechanism | Evidence |
|---|---|---|
| MOTS-c | AICAR / AMPK · muscle glucose | Preclinical (B/C) |
| Tirzepatide | GIP/GLP-1 · weight + glucose | FDA (A) |
| Berberine | AMPK · gut microbiome | Supplement (C) |
| Inositol | IP3 / Akt | Supplement (B) |
| Intervention | When |
|---|---|
| MOTS-c 5–10 mg | Pre-workout |
| BPC-157 250 μg | Daily, post-workout |
| Creatine 3–5 g | Daily |
| Beta-alanine 4–6 g | Daily, divided |
| Scenario | Action | Monitor |
|---|---|---|
| Insulin patient | Reduce 20–30%, titrate by CGM | Daily fingerstick × 4 wk |
| SU on board | Reduce or discontinue | Weekly fasting glucose |
| Active cancer | Consult oncology before initiating | Tumor markers + imaging |
| Agent | Mechanism | Approved Use | Dosing | Human Evidence | Status |
|---|---|---|---|---|---|
| MOTS-c | AICAR↑ via AICARFT inhibition · CK2-β binding · NRF2 co-regulation | None (investigational) | Daily SC · 2–10 mg | Preclinical strong; human PK only | Investigational · WADA S4 (D/C) |
| Metformin | Complex I inhibition → AMP/ATP↑ → AMPK | T2DM 1st line · PCOS · off-label longevity | 500–2000 mg PO daily | Decades of RCT data | FDA-approved (A) |
| AICAR (acadesine) | Direct AMP-mimetic at AMPK γ-subunit | None (research tool; old phase 2 cardiac) | IV infusion (research) | Phase 2 cardiac; discontinued | Research tool (C) |
| Berberine | AMPK activation (mechanism debated; mitochondrial / microbiome) | Supplement | 500 mg PO TID | Meta-analyses for glucose, lipids | Supplement (C) |
| SS-31 (Elamipretide) | Cardiolipin stabilization · OXPHOS efficiency | None (Barth syndrome phase 3) | Daily SC | Phase 3 (Barth) | Investigational (B) |
| NR / NMN | NAD+ precursor · sirtuin co-substrate | Supplement | 250–1000 mg PO daily | Phase 2 metabolic / aging | Supplement (C/D) |
| A-769662 / PF-06409577 | Direct allosteric AMPK activator (ADaM site) | None (research) | Research compound | Preclinical only | Research tool (D) |
| MOTS-c K14Q variant carrier | m.1382A>C polymorphism · reduced CK2 binding | Endogenous | — | n=12,068 Japanese (pro-diabetogenic) | Natural variant (C) |
MOTS-c's clinical safety profile is preliminary — no human therapeutic RCT has been published. The signals below are aggregated from preclinical work, the Reynolds 2021 human pharmacology study, practice-pattern observation in physician-supervised clinics, and mechanistic considerations (AMPK, CK2, NRF2 effects in pregnancy / malignancy / specific populations). Most reported adverse effects are mild and transient; the major safety unknowns are long-term oncology, pregnancy, and dependence-on-context CK2 modulation in non-muscle tissues.
| Condition / factor | Risk level | Applies to | Rationale |
|---|---|---|---|
| Active malignancy | Avoid | All | AMPK activation has context-dependent oncologic effects. No human safety data. Oncologist consultation required before any use. |
| Pregnancy | Avoid | All | AMPK and mTORC1 modulation has theoretical fetal-growth implications. No human pregnancy data. Discontinue ≥2 cycles before planned conception. |
| Lactation | Avoid | All | Excretion into breast milk and infant safety unstudied. Avoid until lactation complete. |
| Pediatric (< 18 years) | Avoid | All | Not studied. AMPK activation during growth has theoretical concerns regarding linear growth and pubertal trajectory. |
| Competitive athlete · WADA-tested | Avoid | All | WADA Prohibited List S4 since 1 Jan 2024 · prohibited at all times in- and out-of-competition. Anti-doping violation independent of medical intent. |
| Type 1 diabetes | Caution | All | Not studied. AMPK activation may modify insulin requirements; CGM monitoring essential. Hypoglycemia risk if insulin not adjusted. |
| Severe insulin resistance on multi-agent therapy | Monitor | T2DM | Dose-reduce hypoglycemia-prone agents (insulin, SU) by 20–30% at MOTS-c initiation. CGM-guided titration recommended. |
| K14Q variant carrier | Monitor | All | Reduced CK2 binding; blunted muscle glucose-uptake response. Likely diminished metabolic / performance effect. Not a safety risk; an efficacy consideration. |
| Severe hepatic impairment (Child-Pugh C) | Caution | All | AMPK activation modulates hepatic substrate handling. No data in advanced cirrhosis. Specialist consultation advised. |
| Severe renal impairment (eGFR < 30) | Caution | All | Limited PK data; partly renal clearance in animal models. Consider dose reduction; monitor renal function. |
| Active autoimmune disease (acute flare) | Caution | All | NRF2 / antioxidant axis modulation has theoretically variable effects on autoimmune inflammation. Specialist input advised. |
| Severe psychiatric instability | Monitor | All | No specific MOTS-c psychiatric signal, but rapid metabolic shifts can transiently affect mood. Continue mental-health support during initiation. |
| Allergy to peptide product / preservatives | Avoid | All | Hypersensitivity to BAC (benzyl alcohol) or to peptide content is a contraindication. Switch to preservative-free reconstitution if needed. |
| Compounded product from unverified source | Avoid | All | Until 503A status is resolved (July 2026), MOTS-c is not eligible for routine 503A compounding. Source must be verified for purity, sterility, identity. |
| Major surgery within 2 weeks | Caution | All | AMPK activation modulates wound-healing metabolism. Insufficient data to determine direction of effect; reasonable to pause during peri-operative period. |
Fasting glucose, fasting insulin (HOMA-IR), HbA1c, lipid panel, CMP (LFTs, renal), TSH, vitamin D. Vital signs (HR, BP). Pregnancy test if reproductive potential. Body composition (DEXA or BIA) optional. CK if planning resistance training. Consider K14Q variant testing in non-responders of East Asian ancestry.
At each escalation step (for protocols with stepwise titration): symptom review (injection-site reactions, GI tolerability, fatigue, headache), fasting glucose if T2DM. Decision: escalate, hold, or step back.
Repeat fasting glucose, fasting insulin, HOMA-IR. HbA1c if metabolic protocol. Symptom diary review. Adherence and cycle-pattern review. Weight, body composition if available. Consider HRV, VO2max if endurance-focused.
Full repeat panel: fasting metabolic markers, lipid, CMP. Assess durability of effect post-washout. Decision: resume cycle, modify dose, or discontinue. For sarcopenia protocols, repeat grip strength / gait speed / SARC-F.
Full metabolic panel. Body composition (DEXA if available). Bone density if >50 years old and on prolonged cycled protocol. Reassess indication and continued benefit. Document any new diagnosis (malignancy, autoimmune, pregnancy planning) that would change risk/benefit.
New malignancy diagnosis, planned pregnancy, severe injection-site reaction, persistent fatigue or new neuro symptoms, unexplained LFT elevation >3× ULN, new diagnosis of severe psychiatric instability, or transition to a setting where WADA testing applies (for athletes).
The MOTS-c literature is dominated by mechanistic preclinical work and a small body of human pharmacology. Below are the studies that define what is known — and what remains the missing translational link. No human therapeutic randomized controlled trial of MOTS-c has been published as of May 2026.
Mass-spectrometric identification of a 16-AA peptide encoded within the mitochondrial 12S rRNA gene. 0.5 mg/kg/day IP × 4 wk in HFD-fed C57BL/6 mice: HOMA-IR −52%, fasting glucose −38%, visceral fat −27%, no change in food intake. Identified folate-cycle / AMPK as the operative mechanism. The discovery paper.
ChIP-seq + RNA-seq in HEK293 and mouse tissue established that MOTS-c translocates from cytoplasm to nucleus under metabolic stress. Co-occupies promoters of ~250 NRF2/ARE-responsive genes; the first MDP shown to act as a transcriptional co-regulator. Redefined MDP biology as a retrograde mitochondrial → nuclear signal.
In 23.5-mo C57BL/6 mice, MOTS-c 5 mg/kg IP 3×/wk × 8 wk doubled treadmill time-to-exhaustion vs vehicle. In healthy young human volunteers, plasma MOTS-c rose +34% during 70% VO2max cycling and remained elevated 4 hours post-exercise. Established MOTS-c as both an exercise-responsive endogenous peptide and a candidate exercise mimetic.
Identified casein kinase 2 regulatory β-subunit (CK2β) as the direct binding partner in skeletal muscle. Wild-type MOTS-c binds CK2β by ITC with low μM affinity; the naturally occurring K14Q variant binds ~16× more weakly and fails to stimulate CK2 activity or GLUT4 translocation in C2C12 myotubes. Provides target-engagement evidence for the muscle glucose-uptake phenotype.
Genotyping in 12,068 Japanese adults established the m.1382A>C polymorphism (encoding K14Q) as associated with a pro-diabetogenic phenotype. Carrier frequency ~6% in East Asian populations. Originally proposed as longevity-protective in a smaller centenarian cohort, but expanded population analysis (n=736 supplementary sample) did not support that association.
In ovariectomized C57BL/6 mice, MOTS-c 5 mg/kg IP 3×/wk × 8 wk rescued cortical and trabecular bone loss: trabecular BV/TV +31% vs OVX-vehicle. Mechanism: TGF-β / Smad-driven RUNX2 nuclear translocation in osteoblasts. First demonstration of MOTS-c's anabolic role in skeletal tissue.
In aged-mouse models of sarcopenia, MOTS-c preserved cross-sectional area and grip strength via attenuation of myofiber autophagy. Effect required concurrent muscle loading paradigm for full expression. Mechanistically links MOTS-c to age-related muscle dysfunction.
Quantification of MOTS-c protein content in human skeletal-muscle biopsies across age groups. MOTS-c content decreases significantly with age in human muscle; the decline is partly reversible with endurance training. Provides the human biological rationale for MOTS-c supplementation in age-related metabolic and mobility decline.
WADA added MOTS-c to the Prohibited List under section S4.5 "Activators of the AMP-activated protein kinase (AMPK)" effective 1 January 2024; retained in the 2025 and 2026 lists. Prohibited at all times in- and out-of-competition for athletes subject to WADA-Code-signatory testing. The first regulatory recognition of MOTS-c as a metabolic-modulating agent.
FDA PCAC meeting scheduled 23–24 July 2026 to review MOTS-c, BPC-157, KPV, and TB-500 for inclusion on the 503A Bulks List. Favorable recommendation would permit 503A pharmacy compounding by state-licensed pharmacies; unfavorable recommendation would push the molecule further into FDA enforcement risk. The most important near-term inflection point for clinical availability of MOTS-c in the US.
Multiple preclinical reports describe MOTS-c neuroprotection in hippocampal LTP, oxidative-stress paradigms, and ischemia-reperfusion injury. Mechanism is consistent with NRF2-driven antioxidant defense and AMPK-mediated autophagy regulation. No human cognitive RCT has been published; the neuro protocol on this page is investigational.
As of May 2026, no published phase 2 or phase 3 randomized controlled trial of MOTS-c for any therapeutic indication exists. Several investigator-initiated trials have been registered on ClinicalTrials.gov but have not reported results. The translational gap between strong preclinical mechanism and validated clinical efficacy is the central unresolved question for MOTS-c. The FDA 503A review in July 2026 and any pivotal trial that follows will define clinical positioning.
The MOTS-c field is at an inflection. Eleven years after the Lee 2015 discovery paper, the molecule sits at the intersection of strong preclinical evidence and absent definitive human trial data. The July 2026 FDA PCAC review will determine whether MOTS-c becomes 503A-eligible and accessible through state-licensed pharmacies in the US — or whether further development requires sponsor-led IND filings. Any positive recommendation likely accelerates clinical research; any negative recommendation extends the off-label / research-only period. The K14Q variant population-genetics work has provided the strongest causal evidence to date that the CK2 mechanism operates in humans.
Every section of this page rewrites itself for consumer, clinician, or researcher via the depth selector at the top. Below, the same summary is held at all three layers at once — the clearest way to see how the framing shifts with the reader.
MOTS-c is a tiny protein your own mitochondria make that acts like an exercise signal — it tells your cells to burn sugar and fat more efficiently and to resist some effects of aging. In mouse studies it reverses age-related insulin resistance and lets old mice run far longer on a treadmill, which is why it's being studied for prediabetes, obesity, and metabolic aging. It is not FDA-approved for any use, it's banned for competitive athletes, and the first real human efficacy trial is still running — so today it remains experimental, and anyone using it does so without proven human benefit or long-term safety data.
MOTS-c is a 16-amino-acid mitochondrial-derived peptide encoded by the MT-RNR1 (12S rRNA) gene, acting as a mitokine that activates AMPK via folate-cycle inhibition (AICAR accumulation) and direct CK2 engagement, with stress-dependent nuclear translocation onto NRF2/ARE gene programs. It promotes insulin-independent GLUT4 translocation and suppresses myostatin; circulating levels fall with age and correlate inversely with insulin resistance, BMI, and HbA1c in human cohorts. Practice-pattern dosing is 1–10 mg/day SC in cycled blocks; the only human dosing reference is the engineered analog CB-4211 (25 mg/day SC × 28 d, Phase 1, NCT03998514). The first powered native-peptide efficacy RCT (Matsuda Index, NCT07505745) is recruiting. Prohibited by WADA (S4.4.1, all times); removed from FDA 503A Category 2 in April 2026 with a PCAC review set for July 2026 — neither equals approval.
MOTS-c (MRWQEMGYIFYPRKLR; MW ≈ 2,174 Da; CAS 1627580-64-6; PubChem CID 146675088) is a sORF-encoded microprotein translated from the mitochondrial 12S rRNA locus (mtDNA ~1343–1393). Its primary metabolic mechanism is inhibition of the AICAR-formyltransferase step of the de novo folate/one-carbon cycle, allowing endogenous AICAR to accumulate and allosterically activate AMPK (α1/α2 via γ-subunit CBS domains). In skeletal muscle it binds the regulatory β-subunit of casein kinase 2 (CK2β) to drive GLUT4 translocation independent of insulin; the naturally occurring K14Q variant (m.1382A>C) binds CK2 ~16× more weakly and blunts glucose uptake. Under elevated AMP/ATP it translocates to the nucleus, co-regulating ~250 NRF2/ARE-responsive antioxidant and mitochondrial-biogenesis genes (PGC-1α, OPA1/MFN2 mitofusion). The CK2–PTEN–AKT–FOXO1 axis mediates myostatin suppression; in T cells it attenuates TCR/mTORC1 signaling and expands Tregs. Half-life is short (~30–60 min plasma SC) with no validated human PK model — the basis for the pulse-dosing architecture on this page. Phase 2a efficacy data (NCT07505745) remain pending through ~2027.