Skip to main content
PepStack

Pregnenolone

Neurosteroids
Δ5-PregnenoloneMother hormone

Overview

Pregnenolone is an endogenous steroid hormone synthesized primarily in the adrenal glands, liver, and gonads. It belongs to the chemical class of neurosteroids and serves as a precursor to various other steroid hormones, including progesterone, glucocorticoids, mineralocorticoids, androgens, and estrogens. Often referred to as the 'mother hormone,' pregnenolone plays a crucial role in the biosynthesis of these hormones. Researchers have been investigating its potential roles in various physiological processes and its implications in health and disease. Pregnenolone is primarily studied for its involvement in neuroprotection, cognitive enhancement, and mood regulation. It has been observed to influence memory and learning, and there is ongoing research into its potential therapeutic roles in neurodegenerative diseases such as Alzheimer's disease. Additionally, pregnenolone's role in stress response and its potential anxiolytic effects are areas of active investigation. The mechanism of action of pregnenolone involves its conversion into other steroid hormones, which then exert effects through their respective receptors. Pregnenolone itself is believed to modulate the activity of neurotransmitter receptors, including NMDA and GABA receptors, influencing neuronal excitability and synaptic plasticity. Its actions on these receptors contribute to its neurosteroid classification and its potential effects on the central nervous system. Pharmacokinetically, pregnenolone has a circulating half-life of approximately 20 to 30 minutes. It undergoes extensive first-pass metabolism, which limits its oral bioavailability. The compound is metabolized primarily in the liver, and its metabolites are excreted via the kidneys. Researchers have observed that pregnenolone's pharmacokinetics can vary based on the route of administration. Clinically, pregnenolone is not widely used as a therapeutic agent, and its regulatory status varies by country. It is not approved by the FDA for any specific medical indication, and its use is primarily limited to research settings. Pregnenolone is available as a dietary supplement in some regions, but its efficacy and safety for various health conditions remain under investigation.

Mechanism of Action

Pregnenolone acts on neurotransmitter receptors such as NMDA and GABA receptors, modulating neuronal excitability and synaptic plasticity. This modulation can influence cognitive functions and mood regulation, contributing to its classification as a neurosteroid.

Molecular Data

FormulaC21H32O2
Molecular Weight316.5 g/mol
CAS Number145-13-1
PubChem CID8955

Half-Life & Pharmacokinetics

EndogenousCirculating half-life ~20 to 30 minutes
OralPoor bioavailability due to first-pass metabolism

Pregnenolone's pharmacokinetics can vary significantly based on the route of administration, with oral bioavailability being notably low.

Storage

Temperature

Store at room temperature (15-30°C)

Light

Protect from light

Form

Stable in solid form for extended periods

Notes

Avoid exposure to moisture and extreme temperatures.

Solubility

Pregnenolone is poorly soluble in water but soluble in ethanol and other organic solvents.

Legal Status

🇩🇪DE

Data limited

🇺🇸US

Pregnenolone is not FDA-approved for any specific medical use and is available as a dietary supplement.

🇦🇺AU

Data limited

🇬🇧UK

Data limited

Legal status information is provided for general reference only and may not reflect the most current regulatory changes. Always verify with official government sources before making any decisions.

6 Research Publications

Pregnenolone promotes immune evasion through blocking endogenous retrovirus expression.

Animal

Cell metabolism · 2026

Researchers found that pregnenolone, a steroid hormone, can promote tumor growth and reduce the effectiveness of immunotherapy in mice. They observed that high levels of pregnenolone were linked to mating issues in mother mice, and blocking its effects led to reduced tumor growth and improved treatment outcomes. This study suggests that targeting pregnenolone could be a new approach in cancer therapy.

  • Pregnenolone promotes tumor progression and reduces immunotherapy sensitivity.
  • Elevated pregnenolone levels were found in mother mice with mating deficiencies.
  • Blocking pregnenolone improved tumor growth outcomes and enhanced immunotherapy effectiveness.
PubMed

Hypothalamic pregnenolone mediates recognition memory in the context of metabolic disorders.

Human

Cell metabolism · 2022

Researchers found that a brain chemical called pregnenolone, produced in the hypothalamus, plays a crucial role in memory, particularly in people with obesity and type 2 diabetes. They observed that changes in pregnenolone levels affected memory function, suggesting a link between metabolism and cognitive health.

  • Pregnenolone production in the hypothalamus is linked to recognition memory.
  • Impaired memory was observed in mice on a high-fat diet due to reduced pregnenolone.
  • The study highlights the importance of specific brain neurons in both metabolism and cognition.
PubMed

Forgetting in obesity: The pregnenolone link.

Human

Cell metabolism · 2022

Researchers found that people with obesity may experience cognitive problems due to lower levels of a brain chemical called pregnenolone. This study, which included both animal models and human patients, suggests that issues in the hypothalamus could contribute to memory and thinking difficulties in those with obesity.

  • Impaired production of pregnenolone is linked to cognitive dysfunction in obesity.
  • The study involved both rodent models and human patients.
  • The hypothalamus plays a key role in this cognitive impairment.
PubMed

Stress and drug abuse-related disorders: The promising therapeutic value of neurosteroids focus on pregnenolone-progesterone-allopregnanolone pathway.

Review

Frontiers in neuroendocrinology · 2019

Researchers observed that neurosteroids like pregnenolone and allopregnanolone may play a significant role in stress-related and drug use disorders. They found changes in the levels of these neurosteroids in both animal models and patients with conditions such as depression and anxiety, suggesting their potential as biomarkers for treatment. Ongoing clinical trials are exploring synthetic versions of these neurosteroids for therapeutic use.

  • Pregnenolone and allopregnanolone levels change in stress and drug use scenarios.
  • These neurosteroids may serve as biomarkers for psychiatric disorders.
  • Clinical trials are investigating synthetic analogs for therapeutic applications.
PubMed

Nongenomic actions of neurosteroid pregnenolone and its metabolites.

Review

Steroids · 2016

Researchers observed that neurosteroids like pregnenolone and its derivatives can enhance brain function by improving learning and memory, relieving depression, and promoting neuron survival. These effects occur through interactions with specific proteins in the brain, suggesting that these compounds may be valuable in treating neurological disorders.

  • Pregnenolone and its metabolites enhance learning and memory.
  • They help relieve symptoms of depression.
  • These neurosteroids promote neuron survival and activity.
PubMed

Endocrine effects of masturbation in men.

Human

The Journal of endocrinology · 1976

Researchers observed that levels of certain hormones, including pregnenolone and dehydroepiandrosterone (DHA), significantly increased in young men after masturbation. In contrast, hormone levels remained unchanged in a control group that anticipated masturbation but did not engage in it. The study highlights the importance of collecting blood samples before semen analysis for accurate hormone measurement.

  • Hormone levels increased significantly after masturbation.
  • No changes in hormone levels were found in the control group.
  • Blood samples should be taken before semen collection for accurate results.
PubMed

Track your hormone research in PepStack

Log cycles, set reminders and visualize serum levels.

This page is for informational and research purposes only. All information is based on published scientific literature. Nothing on this page constitutes medical advice or replaces consultation with a qualified healthcare professional.