AICAR (Acadesine)
5-Aminoimidazole-4-carboxamide Ribonucleotide · AMPK Activator
Overview
AICAR is a cell-permeable nucleoside analog that activates AMP-activated protein kinase (AMPK), a key regulator of cellular energy homeostasis. Originally studied for cardiac ischemia protection, it gained attention as an 'exercise mimetic' due to its metabolic effects.
Once inside cells, AICAR is phosphorylated to ZMP, which mimics AMP and activates AMPK. This triggers metabolic pathways typically activated during exercise: increased glucose uptake, fatty acid oxidation, and mitochondrial biogenesis.
Directly activates the master metabolic regulator through ZMP accumulation.
Increases fat burning through AMPK-mediated pathways.
Enhances glucose uptake independent of insulin in some tissues.
Animal studies showed increased running endurance; human data limited.
Mechanism
AICAR is a cell-permeable nucleoside analog that activates AMP-activated protein kinase (AMPK), a key regulator of cellular energy homeostasis. Originally studied for cardiac ischemia protection, it gained attention as an 'exercise mimetic' due to its metabolic effects.
Once inside cells, AICAR is phosphorylated to ZMP, which mimics AMP and activates AMPK. This triggers metabolic pathways typically activated during exercise: increased glucose uptake, fatty acid oxidation, and mitochondrial biogenesis.
Directly activates the master metabolic regulator through ZMP accumulation.
Research areas
- AICAR is a cell-permeable nucleoside analog that activates AMP-activated protein kinase (AMPK), a key regulator of cellular energy homeostasis. Originally studied for cardiac ischemia protection, it gained attention as an 'exercise mimetic' due to its metabolic effects.
- Once inside cells, AICAR is phosphorylated to ZMP, which mimics AMP and activates AMPK. This triggers metabolic pathways typically activated during exercise: increased glucose uptake, fatty acid oxidation, and mitochondrial biogenesis.
- Directly activates the master metabolic regulator through ZMP accumulation.
- Increases fat burning through AMPK-mediated pathways.
- Enhances glucose uptake independent of insulin in some tissues.
- Animal studies showed increased running endurance; human data limited.
- AMPK activation promotes new mitochondria formation over time.
- Original clinical interest; may protect heart tissue during reduced blood flow.
Research notes
- Injection site reactions
- Mild fatigue during adaptation
- Potential hypoglycemia
- Severe hypoglycemia symptoms
- Lactic acidosis symptoms (muscle pain, weakness, difficulty breathing)
- Unusual cardiac symptoms
- Severe fatigue or weakness
- Diabetes (risk of hypoglycemia)
- Cardiac conditions
- Pregnancy or breastfeeding
- Competitive athletes (WADA prohibited)
Reported effects in literature
- AICAR increases glucose uptake independent of insulin in some tissues, creating theoretical hypoglycemia risk especially in non-diabetics with normal insulin sensitivity. Diabetics face more serious risk, which is why AICAR is contraindicated in diabetes. Monitor blood glucose closely, particularly during initial doses.
FAQs
Does AICAR actually work as an 'exercise mimetic' in humans?
Animal studies show AICAR increased running endurance by 44% without training. However, this was mice, not humans. Humans have never been adequately tested for AICAR's endurance effects, so calling it an exercise mimetic is speculative. The compound does activate AMPK and increase fat oxidation, but real-world performance gains in people are unproven.
Is AICAR banned in sports and why?
Yes, AICAR is WADA prohibited. While it's not anabolic per se, it provides competitive advantage through enhanced metabolic efficiency and endurance. Athletes competing under WADA rules must avoid it entirely due to testing likelihood and strict liability regulations.
How does AICAR differ from GW501516 for metabolic enhancement?
AICAR activates AMPK, the master metabolic regulator, increasing fatty acid oxidation and glucose uptake. GW501516 is a PPARδ agonist with different downstream effects. They're often stacked because they target complementary pathways—AMPK plus PPARδ activation produces synergistic metabolic effects.