Pregnenolone is a neurosteroid and steroid hormone precursor, synthesized from cholesterol. It’s the first step in the steroid hormone cascade.
🧠 Key Physiological Functions of Pregnenolone
1. Hormone Precursor
- Acts as a building block for:
- Progesterone
- Cortisol
- Aldosterone
- Testosterone
- Estrogens
- DHEA
- Essential for maintaining hormonal balance in the body.
2. Brain & Nervous System Effects
- Neurosteroid activity: Synthesized in the brain, it modulates:
- Synaptic transmission
- Neuroplasticity
- Myelination
- Influences mood, motivation, and cognitive function.
3. Memory & Cognitive Enhancement
- Animal and limited human studies suggest it may:
- Enhance memory formation
- Improve learning capacity
- Protect against neurodegeneration
- Protects brain cells from injury and oxidative stress.
- Thought to modulate NMDA and GABA-A receptors, affecting excitability and inhibition in the brain.
4. Anti-fatigue & Stress Modulation
- May help the body cope with stress by supporting adrenal hormone production (e.g., cortisol).
- Possibly improves energy levels and resilience under stress.
- May have anti-anxiety and antidepressant effects by modulating brain neurotransmitters.
5. Immune System Modulation
- Some evidence suggests pregnenolone may influence immune responses, although this is less understood.
🧬 Where Is It Made?
- Adrenal glands, gonads, brain, liver, and retina.
⚖️ Clinical Relevance
- Levels decline with age.
- Studied (but not definitively proven) for potential roles in:
- Alzheimer’s disease
- Depression
- Schizophrenia
- Fatigue syndromes
- Hormonal deficiencies
📉 Decline With Age
- Pregnenolone levels peak in early adulthood and decline significantly with age, potentially affecting hormone balance, memory, and energy.