MOTS-c is a 16-amino-acid peptide whose sequence is encoded in the mitochondrial genome, unlike other peptides which are encoded by the nuclear genome. Under normal conditions, MOTS-c is produced inside mitochondria and is released into the cytoplasm. Under metabolic stresses such as caloric restriction, exercise, and hypoxia, MOTS-c translocates into the nucleus to control nuclear gene expression. This process is unprecedented as it is a method of communication from mitochondria to the nucleus that allows genes in cells to be regulated.
The main pathway of activation is AMPK activation. The action of MOTS-c leads to the inhibition of the folate-methionine cycle and the buildup of AICAR (an endogenous activator of AMPK) which changes a cell's metabolism from relying on glucose to relying on fat. The process was confirmed in the experiments with mouse models where mice exhibited reduced fat mass and improved insulin and exercise performance. The level of MOTS-c decreases as a person gets older while its level in blood and muscles increases after exercise. This results in the perception of MOTS-c as an exercise mimetic by scientists. MOTS-c is not a hormone but a signal released by the body in reaction to physical activity.
A variant (m.1382A>C) of the MOTS-c coding region has been linked with extreme longevity of Japanese populations and adds a human genetics dimension to an otherwise purely rodent story. Although this association does not imply causality, it is the sort of signal that keeps clinical interest alive despite the fact that years have passed since the CohBar program ended.
For a full mechanistic profile, the MOTS-c compound page in the Get US Peptides peptide library covers the folate-cycle pathway in detail.
Findings obtained from mouse studies have been replicated across various independent research teams. The administration of MOTS-c subcutaneously in a mouse model of obesity yielded reductions in fat mass, enhanced glucose tolerance and increased fat oxidation in the muscle. In old mouse, the treatment restored the capacity for exercise to the level comparable to that seen in younger mice. In experiments with bone studies, MOTS-c resulted in decreased activity of osteoclasts, and in a model of muscle wasting it exerted anti-catabolic properties during inflammatory challenges. These results are from animal experiments; their significance for humans is unknown.
Patient data came from a single clinical trial focused on CohBar’s CB4211, a drug based on MOTS-c, a peptide engineered to add greater stability. The initial phase of the trial (1a) included only healthy participants, while the second phase (1b) involved patients with NASH and obesity. The initial results published in 2021 indicated that CB4211 was well-tolerated and caused no serious side-effects in the participants. The trial also showed some changes in fasting blood glucose and body weight. CohBar described the results as being encouraging before the company merged and abandoned the project. The results underlying phase 1b have not yet been published in a peer-reviewed journal and, therefore, have certain limitations, according to the researchers.
I do mention it every time researchers inquire about the "before-and-after" results of MOTS-c: the studies on mice were carried out on continuous or almost everyday doses of high-weight-adjusted doses, while for the phase one study an analogue, not the native MOTS-c was used. It is therefore impossible to extrapolate results from either mice or the clinical trial to a particular human outcome.
CB4211 was administered subcutaneously. Phase 1a dose-escalation in healthy volunteers involved multiple ascending doses; CohBar's investor communications indicated that doses ranged from 0.5 mg/kg to 2 mg/kg, but the complete dose range table has never been published in a peer-reviewed journal. Phase 1b in NASH/obesity patients involved a fixed dose for 12 weeks. The primary outcomes were safety and tolerability, while secondary outcomes included body weight, liver fat using MRI-PDFF and fasting glucose. Body weight showed a decrease of approximately 2-3% in the treated group over 12 weeks versus placebo and fasting glucose improved, but neither of these outcomes was statistically significant according to published press release information due to small sample size rather than clearly negative outcome.
The practical relevance of this research protocol indicates that the phase 1 results confirm the safety of subcutaneous administration within low dosing range, however, they have not identified any particular dose required for the endpoint. Research protocols mentioning a dose between 5-10 mg per injection with 2-3 injections weekly derive their information from preclinical studies and phase 1 general dosing range and do not quote a specific dose-response curve.
The dosing pattern for MOTS-c in established studies is focused on weekly totals rather than daily amounts due to the fact that it is usually injected 2 to 3 times per week. Below is the calculation for the 10 mg and 20 mg vials of MOTS-c using 2 mL as the reconstitution volume.
| Protocol Stage | Injection Dose | Frequency | Weekly Total | Volume / Injection (10 mg Vial, 2 mL Recon) | Volume / Injection (20 mg Vial, 2 mL Recon) |
|---|---|---|---|---|---|
| Loading (weeks 1-2) | 5 mg. | Daily (7x). | 35 mg. | 1.0 mL. | 0.50 mL. |
| Standard Maintenance | 5 mg. | 3x per week. | 15 mg. | 1.0 mL. | 0.50 mL. |
| Standard Maintenance | 10 mg. | 2x per week. | 20 mg. | 2.0 mL (full vial). | 1.0 mL. |
| Standard Maintenance | 10 mg. | 3x per week. | 30 mg. | 2.0 mL (full vial). | 1.0 mL. |
| Cycle Length | - | - | 4-8 weeks. | - | - |
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A few math pitfalls worth watching. A 10 mg vial reconstituted in 2 mL of bacteriostatic water gives <span style="color: #1a1a1a; font-weight: 600;">5 mg/mL</span>: a 5 mg dose is exactly 1.0 mL, and a 10 mg dose empties the vial in one shot. A 20 mg vial reconstituted in 2 mL gives <span style="color: #1a1a1a; font-weight: 600;">10 mg/mL</span>: 5 mg = 0.5 mL, 10 mg = 1.0 mL, which allows four 5 mg injections per vial. Published protocols time administration fasted, pre-exercise, into subcutaneous sites such as the abdomen or thigh.
Published protocols show no dose variation by gender. There are no studies to date indicating any gender needs an adjusted dose figure.
The <a href="https://uspeptidelabs.co/products/mots-c" style="color: #1a1a1a; font-weight: 500;">MOTS-c 20 mg vial at US Peptide Labs ($95.00)</a> is the more economical format for multi-week research cycles at 5 mg per injection.
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The most reported mistake that people make is the reconstitution error. The lyophilized powder is stable either refrigerated or frozen under light- and moisture-free conditions. On reconstitution, the vial should be kept in a fridge at a temperature between 2°C and 8°C and used within about a month. Freezing the reconstituted solution is not allowed.
Reconstitution steps for a 20 mg vial:
| Step | Action | Reason / Detail |
|---|---|---|
| 1. Bring to Room Temperature | Allow the vial to reach room temperature before opening. | Prevents condensation inside the stopper. |
| 2. Add Bacteriostatic Water | Slowly inject 2 mL of bacteriostatic water. | Direct it to the side of the vial, not onto the powder. |
| 3. Dissolve | Gently swirl the solution. | Do not shake or vortex. Dissolves in about 60 seconds at room temperature. |
| 4. Label the Vial | Mark the reconstitution date and concentration. | 2 mL into a 20 mg vial = 10 mg/mL. |
| 5. Store | Refrigerate immediately. | Discard after 4 weeks. |
To read the COA specific to the lot for every vial, COA reading guide at Get US Peptides shows the process of understanding the meaning of the test lines and identifying the necessary numbers.
Phase 1 CB4211 results showed no critical side effects. This is the most powerful safety statement available, but it applies to the analogue which was taken subcutaneously over a period of 12 weeks in a controlled clinical environment. This does not imply that MOTS-c cannot have side effects, but only shows that the tested dosage has not caused serious ones among those tested.
Side effects reported across research use and the phase 1 program:
Injection site - mild swelling, redness, temporary discomfort. Happens with every subcutaneous peptide injection.
Mild fatigue, particularly in the first week of a new cycle.
Feeling faint or having a sensation of low blood sugar upon injecting in a fasted condition. This agrees with the AMPK-mediated mechanism responsible for the decline in blood sugar and is something to watch out for in any experimental design using fasting while administering.
There are no human safety data that have been documented for periods longer than 12 weeks. Although that fact seems trivial, it is, instead, a significant gap in research. Any research design with a duration longer than eight weeks lacks any human safety data for that time period.
No, MOTS-c is not FDA-approved for any human or animal uses. The drug application was never submitted, and the CohBar/CB4211 effort was abandoned after the acquisition of the company prior to phase 2. The product is available only for research purposes in the U.S.
In infamous September of 2023, FDA classified MOTS-c in Category 2 of the list of bulk substances under the FDCA of 503A, which is applicable for medicines with serious safety issues. Subsequent regulatory updates removed MOTS-c to be in Category 2, which did not mean that it would be moved to the positive list of materials allowed for compounding. Thus, in 2026 , no 503A compounding pharmacy can legally compound MOTS-c for the sake of patients. It is not available for prescription purpose. Suppliers claiming to be chemical suppliers of research purpose materials are regulated in a different way than 503A/503B pharmacies.
The US Peptide Labs has clearly stated that it is not a compounding pharmacy but a chemical supplier. The MOTS-c offered at US Peptide Labs is intended solely for laboratory research purposes.
Acquisition of MOTS-c as a research chemical for laboratory purposes is permitted in the United States. Under the DEA scheduling system, MOTS-c is not subject to any regulations. The restriction applies only to compounding the drug for human use (503A).
For elite competitors, the situation is more clear-cut. WADA bans MOTS-c as part of S4.4 - metabolic enhancers, in particular, AMPK stimulants. AICAR is listed in this category, with MOTS-c using the AMPK method. The NCAA also adheres to the WADA banned substances list. Hence, every researcher who also happens to be an elite athlete must understand that any WADA prohibited substance will show on a drug test, while an ACK-AMPK positive test will carry the same consequences as any other S4 violation.
The metabolic peptides research guide at Get US Peptides covers the regulatory landscape for this compound class in more detail.
The reason these four compounds are seen together in research contexts is that all of them are involved in metabolism studies - fat burning, energy outputs, insulin response. However, they do not share the same mechanisms of action, which is an important consideration for research design.
| Compound | Type | Primary Mechanism | Route | Human Trial Data | WADA Status | Research Profile Link |
|---|---|---|---|---|---|---|
| MOTS-c | Mitochondrial peptide (16 AA). | AMPK activation via folate-methionine cycle; nuclear gene regulation. | Subcutaneous injection. | Phase 1 (CB4211 analog, 2021) - safe, preliminary metabolic signals. | Prohibited (S4.4). | MOTS-c library. |
| AOD-9604 | HGH fragment peptide. | Beta-3 adrenergic receptor; lipolysis stimulation; no IGF-1 axis. | Subcutaneous injection or intranasal. | Phase 2/3 trials for obesity (Metabolic Pharmaceuticals, 2000s) - failed primary endpoint. | Not listed (as of 2026). | - |
| SLU-PP-332 | Small molecule (non-peptide). | ERR alpha/gamma agonist; mimics exercise transcriptional program. | Oral (in mouse studies). | No human trials published. | Not listed (as of 2026). | - |
| AICAR | Nucleoside analog. | Direct AMPK activator (AMP mimetic). | Intravenous or subcutaneous injection. | Used in cardiac surgery protocols; metabolic research trials. | Prohibited (S4.4, named explicitly). | - |
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The main difference between MOTS-c and AICAR is that AICAR acts directly as an AMPK activator through the mimicking of AMP, thus activating AMPK. MOTS-c works through an indirect route to activate AMPK through some metabolites of the folate cycle, but the time of action may be different. MOTS-c and AICAR are prohibited substances as listed by WADA for that reason. SLU-PP-332 is a small molecule that can be taken orally in mice, while MOTS-c has no such property since it is degraded in the gastrointestinal tract. AOD-9604 works on a different receptor system and does not involve AMPK action; thus, equating it to MOTS-c for "body fat loss research" blends two unrelated biological pathways.
AOD-9604, SLU-PP-332 and AICAR are not available at US Peptide Laboratories. If you have a broader interest in metabolic peptides, please refer to the performance and vitality collection.
CJC-1295 / Ipamorelin, which is a GHRH analogue and ghrelin mimetic, has effects on growth hormone release from the pituitary, which in turn influences body composition through its effects on IGF-1. MOTS-c does not have an effect onGH/IGF-1 axis. CJC-1295/Ipamorelin is used by researchers who are conducting research on GH-induced anabolism, using the pulses of GH during sleep. MOTS-c is used for research on the effects of mitochondrial metabolic signaling and AMPK-induced fat oxidation. Stacking the two of them is not contraindicated according to animal studies.
Mitochondrial function investigations focus more and more on combination of compounds than on isolated compounds as mitochondrial well-being is dependent on numerous processes that occur in parallel. Three items from the catalog of the US Peptide Labs can be seen next to MOTS-c in the context of published studies on mitochondria:
NAD+ - the primary electron carrier involved in oxidative phosphorylation; levels decline as one ages; studies have placed it with different AMPK activators to have some synergy in terms of metabolic effects. The NAD+ library entry contains the data from interactions of sirtuins and PARP.
LINK_0 is a tetrapeptide that targets mitochondria, accumulating at the mitochondrial inner membrane while relieving oxidative stress, and has been experimentally examined on models of aging, cardiovascular insufficiency, and cachexia. The LINK_1 explains how the interaction with cardiolipin occurs.
The 5-Amino-1MQ is a tiny molecule inhibition NNMT that is being researched for the impact it has on both NAD+ availability and adipocyte metabolic process. The 5-Amino-1MQ entry discusses the pathway of NNMT-SAM.
These have not been proven combination practices through published human studies. They are mechanistically complementary research tools available collectively in the combination research protocols guide for researchers scheming multicompound mitochondrial researches. The peptides for energy research overview describes the context of each.
When it comes to acquiring MOTS-c for scientific purposes, there are three important aspects to take into account: checking whether it is pure according to a separate method, tracing back the lots, and synthesizing it in the USA so that shipping can be trusted. Here is what US Peptide Labs has to propose in this respect.
| Specification | US Peptide Labs MOTS-c 20 mg |
|---|---|
| Vial Size | 20 mg lyophilized powder, 10 mL vial. |
| Purity | 99.3% by HPLC. |
| Testing Lab | AxisPharm (independent); 5 lots on file. |
| Lot Traceability | Lot number stamped on vial base; lot-specific COA available. |
| Synthesis Origin | US laboratories. |
| Price (Single Unit) | $95.00. |
| Price (2+ Units) | $90.25 each. |
| Price (5+ Units) | $85.50 each. |
| Shipping | Free US shipping on orders from $70; ships from US facility with tracking. |
| Age Requirement | 21+. |
| Use Designation | Research use only; chemical supplier, not a pharmacy. |
The most important piece of data in the table would be the AxisPharm COA. AxisPharm is a third-party analytical laboratory and not an internal testing laboratory. The five lots on record mean that a 99.3% purity is achieved throughout production cycles instead of being one-time result. The COA documentation can be found at the quality and COA page while COA reading guide provides insight on interpreting HPLC purity, mass verification, and endotoxin results.
The COAs of MOTS-c from a number of suppliers have been looked into by me for a period of two years. Lack of lot traceability is found to be the most noticeable gap rather than the lack of purity. A COA lacking the lot number for the vial that is being handled is solely a marketing paperwork. Lot number printed on the base of the vial at US Peptide Labs serves to fill this gap.
Those doing comparative analysis can find members of this class, including Tirzepatide, among options in the field of metabolic research. The GLP-1 and weight management collection shows the mechanisms of various classes of compounds.
MOTS-c is a peptide consisting of 16 amino acids, and is coded by the organism’s mitochondrial DNA, having been discovered in 2015. It works by activating AMPK, that promoting fat burning and improving insulin sensitivity in various animal models due to the folate-methionine cycle. If a body is under metabolic stress circumstances, the corresponding peptide enters nucleus of the cell and starts regulating gene expression directly. Levels of MOTS-c in human blood decrease as the age goes, while with all kinds of physical activity, the levels of MOTS-c rise in blood, thus were given the name of ”exercise mimetic". No human treatment has been approved yet.
Most research protocols tend to utilize 5-10 mg per shot, with doses given 2-3 times a week via subcutaneous injection, which results in a weekly dose of 10-30 mg. Some protocols might start with a 5 mg daily loading dose initially for 1-2 weeks, followed by dosing 2-3 times per week. Complete vial calculations are available at the MOTS-c dosage guide and the dosage calculator. There is no gender-based difference in dosing in any of the research protocols.
CohBar's drug CB4211 (similar to MOTS-c) underwent phase one trial in healthy subjects and after that phase one trial in patients with NASH and obesity in 2021. There were no reports of serious complications. Some early signs were seen in glycemia and body weight in the patients with NASH and obesity after 12 weeks. The project had to be frozen due to the merger of CohBar with another company. There has been no publication of the phase one results as of mid-2026 either in any scientific journal or as any report.
No. MOTS-c is not approved by the FDA for any purpose. Furthermore, it is not included in 503A positive list of approved compounds, meaning compounding pharmacies are not permissible to dispense this medication to patients. Various suppliers sell it in the USA as a chemical meant only for research purposes and are governed by regulations outside the pharmacy domain.
Acquiring MOTS-c as a research chemical is completely legitimate in the United States. The substance is not classified by the DEA. However, for competitive sportsmen, MOTS-c is banned by WADA S4.4 (metabolic modulators, AMPK activators) just as NCAA abides by the list defined by WADA. Aspirants in sports who test positive for the substance will face the same penalties as all other S4 violators.
There have been no reports of any significant side effects from the phase 1 trial. The side effects reported during the study include redness and slight swelling at the injection site, mild fatigue at the start of the cycle, and feeling lightheaded or experiencing low blood sugar sensations during the injection. However, there is no long-term safety data regarding the drug.
AOD-9604 is a portion of human growth hormone which engages beta-3 adrenergic receptors for the purpose of promoting lipolysis. It does not have any mechanism involving AMPK activation and is not prohibited by WADA. AICAR is a direct AMPK activator (AMP mimetic) that directly affects AMPK and is explicitly identified under WADA S4.4. MOTS-c, on the other hand, activates AMPK indirectly through the accumulation of products of the folate cycle and is also prohibited by WADA. Therefore, these three substances study the processes of fat metabolism via three distinct pathways and cannot be considered as interchangeable research instruments.