AICAR
A non-peptide AMPK-activating nucleotide analog studied as an "exercise mimetic" for endurance, fat oxidation, and metabolic regulation.
AICAR (acadesine) is a cell-permeable nucleoside analog and prodrug that is phosphorylated intracellularly to ZMP, a molecule that mimics AMP and directly activates AMP-activated protein kinase (AMPK) — the cell's central energy sensor. Activating AMPK increases fatty acid oxidation, glucose uptake, and mitochondrial biogenesis, partially phenocopying the effects of aerobic exercise and caloric restriction. Despite being grouped with peptides in research catalogs, AICAR is not a peptide; its performance-related reputation derives almost entirely from a landmark 2008 rodent study, with human data limited to specific indications such as type 2 diabetes and cardiac surgery.
Class
Non-peptide nucleoside/nucleotide analog (AMPK activator)
Routes
Subcutaneous, Intravenous
Category
Weight Loss & Metabolic
Researched benefits
What it's studied for
Endurance / exercise mimicry
In a landmark 2008 mouse study, AICAR administration increased running endurance by roughly 44% without physical training and shifted muscle toward more oxidative fiber types. This exercise-mimetic effect has not been replicated or evaluated in any human study.
Fat oxidation
AMPK activation by AICAR stimulates fatty acid oxidation and, in a human trial in type 2 diabetics, intravenous AICAR inhibited whole-body lipolysis and lowered circulating free fatty acids — evidence the pathway is pharmacologically active in humans.
Glucose regulation
AMPK activation upregulates GLUT4 expression and glucose uptake and suppresses hepatic gluconeogenesis; intravenous AICAR reduced hepatic glucose output in patients with type 2 diabetes.
Mitochondrial biogenesis
AICAR increases mitochondrial biogenesis via the AMPK–PGC-1alpha axis, a mechanism repeatedly demonstrated in rodent and cell-culture models.
Cellular stress protection (preclinical)
In cell models, AICAR has reduced endoplasmic reticulum stress and modulated autophagy through AMPK, effects explored in contexts ranging from retinal cells to endothelial and lamellar tissue.
Mechanism
How it works
AICAR is a cell-permeable nucleoside analog that, once inside the cell, is phosphorylated to its monophosphate form ZMP (AICA ribotide). ZMP structurally mimics AMP, the molecule that accumulates when cellular energy runs low, and directly activates AMP-activated protein kinase (AMPK) — the master energy-sensing kinase — even when actual energy charge is normal.
Once AMPK is switched on, the cell behaves as if it needs to generate energy: fatty acid oxidation increases, GLUT4-mediated glucose uptake rises, mitochondrial biogenesis is stimulated through the PGC-1alpha program, autophagy is promoted, and energy-consuming processes such as hepatic gluconeogenesis are suppressed. Because these are the same adaptations driven by sustained aerobic exercise and caloric restriction, AICAR is described as an "exercise mimetic."
This pharmacology has been validated in humans only in narrow contexts: intravenous AICAR in type 2 diabetic patients reduced hepatic glucose output and inhibited lipolysis via AMPK, and acadesine has been trialed as a cardioprotective agent in cardiac surgery. The dramatic endurance and fiber-type effects seen in mice have not been reproduced or studied in humans, so the metabolic effects observed in patients should not be extrapolated to athletic or performance use.
Evidence
Research & clinical studies (8)
Intravenous AICAR administration reduces hepatic glucose output and inhibits whole body lipolysis in type 2 diabetic patients
In a crossover trial (n=10 male type 2 diabetics), intravenous AICAR activated AMPK, reduced hepatic glucose output, and decreased circulating free fatty acids, confirming in vivo AMPK activation as a metabolic mechanism in humans.
PMID 18709353Targeting AMPK Networks for Male Reproductive Health: Mechanisms and Emerging Therapies
AMPK links metabolic health to male reproductive processes, and pharmacological AMPK agents including AICAR show promise for improving reproductive outcomes in metabolic dysfunction.
PMID 42121908Pharmacological inhibition of TRPM4 channel stabilizes atherosclerotic plaque via inhibiting AMPK-Beclin1-mediated autophagy
AICAR, acting as an AMPK agonist, reversed the protective effect of TRPM4 inhibition against excessive autophagy and apoptosis in oxLDL-exposed endothelial cells.
PMID 42203062Berberine Regulates Hepatic Fatty Acid Metabolism via AMPK/SIRT1/PGC-1α Pathway
Activation of the AMPK/SIRT1/PGC-1α axis reduced hepatic lipid accumulation, supporting the pathway's relevance to fatty liver disease with type 2 diabetes.
PMID 42126802Thapsigargin-induced autophagic flux impairment and inflammation are potentiated by CLN3 deficiency and alleviated by AICAR in human ARPE-19 cells
AICAR alleviated autophagic-flux impairment and inflammation in human retinal pigment epithelial cells, including under CLN3 deficiency.
PMID 42308764The AMPK-PGC-1α-SIRT3 axis mediates mitochondrial metabolic dysfunction and neuronal senescence induced by Al(mal)3 exposure in HT22 hippocampal neuronal cells
The AMPK–PGC-1α–SIRT3 axis mediates mitochondrial dysfunction and neuronal senescence, implicating AMPK signaling in neuronal metabolic stress.
PMID 42263892Protective effects of adiponectin receptor agonists against equine lamellar endoplasmic reticulum stress
Adiponectin receptor agonists including AICAR reduced endoplasmic reticulum stress and inflammatory markers in equine lamellar cells, suggesting a protective mechanism relevant to laminitis.
PMID 42161434MiR-27b-3p suppresses proliferation and testosterone synthesis in goat Leydig cells by activating the AMPK pathway through PPARG targeting
miR-27b-3p suppresses Leydig-cell proliferation and testosterone synthesis by targeting PPARG and modulating AMPK signaling.
PMID 42134159Safety
Side effects & considerations
Commonly reported effects
Contraindications & cautions
- Use by competitive athletes (WADA-prohibited, detectable in testing)
- Any use outside a controlled research setting given the absence of human performance/safety data
In limited human clinical trials of acadesine for cardiac surgery, side effects have generally been mild — typically transient hypotension and hyperuricemia — and preclinical rodent studies have not surfaced significant toxicity at researched doses. Long-term safety in humans for exercise-mimetic dosing is unknown, and the WADA prohibition reflects performance-enhancement concerns rather than an identified safety problem.
FAQ
AICAR — common questions
Is AICAR a peptide?
No. AICAR is a nucleotide analog — specifically an analog of adenosine monophosphate — not a peptide. It is grouped with peptides in research-chemical catalogs because of an overlapping buyer audience and shared metabolic-research interest.
How does AICAR work?
It is converted inside cells to ZMP, which mimics AMP and directly activates AMPK, the central energy-sensing kinase. AMPK activation increases fatty acid oxidation, glucose uptake, and mitochondrial biogenesis, partially reproducing the cellular response to exercise.
Does AICAR actually improve endurance in humans?
Human evidence for endurance improvement is essentially absent. The famous "endurance mimetic" finding comes from a 2008 mouse study (Narkar et al., Cell), where mice ran ~44% longer without training. This has not been clinically established in humans.
Will AICAR show up on a drug test?
Yes. AICAR is on the WADA Prohibited List (Section S4.5 — Metabolic Modulators), and modern testing methods detect AICAR and its metabolites. Competitive athletes testing positive face sanctions.
Is AICAR legal to purchase?
In most jurisdictions AICAR is legal to buy as a research chemical for laboratory use, and possession by non-athletes for research is generally legal. It is, however, prohibited by WADA for competitive sport.
What has AICAR been studied for in humans?
Human work is narrow and indication-specific: intravenous AICAR in type 2 diabetes (reducing hepatic glucose output and lipolysis) and acadesine as a cardioprotective agent in cardiac surgery. No Phase 3 trials exist for exercise capacity, weight loss, or general metabolic use.
Is there a recommended dose?
No validated human dose exists for performance or weight-loss use. AICAR is not approved for human consumption, and reputable references decline to recommend a dose, emphasizing consultation with a licensed physician.
