Supplement
Muira puama is an Amazonian shrub whose bark and roots yield extracts that appear to nudge brain chemistry, including acetylcholine breakdown and certain serotonin receptors. In studies of memory and thinking, the extract improved memory retrieval in young and aged mice, but the evidence is limited. No human cognitive trials exist, so it is unknown whether this carries over to people.
- Updated
- How we grade
- 9 studies cited
- Best evidence
- Grade C
- Conditions studied
- 4
- Outcomes
- 6
- Graded outcomes
- 0015
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Cognitive Function In rodent models, P. olacoides extract consistently improved memory retrieval in step-down avoidance and object recognition tasks in both young and aged mice across multiple studies. Effects are mediated through acetylcholinesterase inhibition (15-33% in hippocampus) and serotonin 5-HT2A receptor modulation. No human cognitive trials exist. | Improves (the measure goes up) | Moderate effect | 5 studies | |||
Studies that measured cognitive function
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| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Neuroprotection In preclinical models, P. olacoides extract protected rat hippocampal slices from oxygen-glucose deprivation, reduced brain lipid peroxidation and free radical production in aged mice, and prevented amyloid-beta(1-42)-induced cognitive impairment and amyloid deposits in a mouse Alzheimer's model. All studies from a single research group. | Improves (the measure goes up) | Moderate effect | 3 studies | |||
Antioxidant Status
- Brain Antioxidant Status: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Brain Antioxidant Status In aged mice, P. olacoides extract (100 mg/kg) reduced free radical production in hypothalamus, decreased lipid peroxidation across multiple brain regions, and increased catalase and glutathione peroxidase activity in hippocampus and cortex. | Improves (the measure goes up) | Moderate effect | 3 studies | |||
General
- Depressive Symptoms: improves
- Libido and Sexual Function: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Depressive Symptoms In a mouse forced swim test, P. olacoides extract (15-100 mg/kg i.p. and 300 mg/kg oral) produced dose-related anti-immobility effects mediated through beta-adrenergic and dopamine D1 receptor pathways. No human antidepressant trials have been conducted. | Improves (the measure goes down) | Small effect | 2 studies | |||
Studies that measured depressive symptoms | ||||||
| Libido and Sexual Function Three open-label, uncontrolled human studies reported improvements in self-reported libido and sexual function (62% of 262 men reported a 'dynamic effect'; 85% of 26 men reported improved libido). The largest study (202 women) used a combination product with Ginkgo biloba. All lacked placebo controls and blinding. | Improves (the measure goes up) | Small effect | 1 study | 490 people | ||
Studies that measured libido and sexual function | ||||||
Anxiety Disorders (Other)
- Stress Resilience: changes; see studies
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Stress Resilience In a mouse unpredictable chronic mild stress model, P. olacoides extract prevented stress-induced anxiety-like behavior and hyperglycemia, suggesting adaptogen-like properties. Notably, it did not produce direct anxiolytic effects in unstressed animals. | Changes; see studies | Small effect | 2 studies | |||
Studies that measured stress resilience | ||||||
Key findings
- Cognitive FunctionImproves (the measure goes up)
- NeuroprotectionImproves (the measure goes up)
- Brain Antioxidant StatusImproves (the measure goes up)
Studies cited
9 studies from PubMed
- Anti-stress effects of Ptychopetalum olacoides in models of stress
- Acetylcholinesterase inhibition in cognition-relevant brain areas of mice treated with Ptychopetalum olacoides
- Antidepressant-like profile of Ptychopetalum olacoides Bentham in mice
- Serotonin receptors contribute to the promnesic effects of P. olacoides (Marapuama).
- Promnesic effects of Ptychopetalum olacoides in aversive and non-aversive learning paradigms
- Antioxidant activities of Ptychopetalum olacoides in the aging mouse brain
- Effects of Ptychopetalum olacoides on memory retrieval in young and aging mice
- Neuroprotective effects of Ptychopetalum olacoides on oxygen-glucose deprivation in rat hippocampal slices
- Anxiogenic properties of Ptychopetalum olacoides Benth. (Marapuama)