Glossary of Terms

AMP-activated protein kinase, an enzyme that plays a key role in cellular energy homeostasis. Often called the "metabolic master switch," it's activated during low energy states and is a target for longevity interventions like metformin and exercise.

The body's cellular "cleanup" process where cells break down and recycle damaged components. Enhanced by fasting, exercise, and certain compounds like rapamycin. Considered a key mechanism in healthy aging.

The proportion of a substance that enters circulation when introduced into the body and is able to have an active effect. Higher bioavailability means more of the compound reaches its target.

Body Protection Compound-157, a synthetic peptide derived from a protein found in gastric juice. Studied for potential tissue healing and gut repair properties, primarily in animal research.

Custom-made medications prepared by specialized pharmacies to meet specific patient needs. Often used for peptides and hormone therapies. Quality and regulation vary significantly between compounding pharmacies.

A molecule that activates two different receptors simultaneously. Tirzepatide is a dual GLP-1/GIP agonist, which may explain its enhanced weight loss effects compared to single-agonist medications.

The study of changes in gene expression that don't involve alterations to the DNA sequence. Epigenetic "clocks" measure biological age by looking at DNA methylation patterns.

Glycyl-L-histidyl-L-lysine copper, a naturally occurring copper peptide found in human plasma. Used topically for skin anti-aging and wound healing, with some research on systemic effects.

An incretin hormone that stimulates insulin release and plays a role in fat metabolism. Tirzepatide activates both GLP-1 and GIP receptors, potentially enhancing metabolic effects.

An incretin hormone that regulates blood sugar, slows gastric emptying, and reduces appetite. GLP-1 receptor agonists like semaglutide and tirzepatide are used for weight loss and diabetes management.

The time it takes for the concentration of a substance in the body to reduce by half. Semaglutide's long half-life (~7 days) allows for once-weekly dosing.

The period of life spent in good health, free from chronic disease and disability. Distinguished from lifespan (total years lived), healthspan focuses on quality rather than quantity of years.

A biological phenomenon where low doses of a stressor produce beneficial adaptive responses. Examples include exercise, cold exposure, and fasting, mild stresses that trigger protective mechanisms.

Hormones released by the gut after eating that stimulate insulin secretion and regulate blood sugar. GLP-1 and GIP are the two main incretins targeted by weight loss medications.

Chronic, low-grade inflammation associated with aging. This persistent inflammatory state contributes to many age-related diseases and is a key target for longevity interventions.

Freeze-dried. Many peptides are sold in lyophilized (powder) form for stability and require reconstitution with bacteriostatic water before use.

A first-line diabetes medication that works by reducing glucose production in the liver and improving insulin sensitivity. Being studied for potential anti-aging effects in the TAME (Targeting Aging with Metformin) trial.

Mechanistic target of rapamycin, a protein complex that regulates cell growth, proliferation, and survival. Inhibiting mTOR (with rapamycin) extends lifespan in multiple species and enhances autophagy.

A coenzyme found in all living cells that's essential for energy metabolism and cellular repair. NAD+ levels decline with age, leading to interest in precursors like NMN and NR.

A precursor to NAD+ that the body converts into the active coenzyme. Supplementation aims to boost NAD+ levels, though human evidence is still limited.

Another NAD+ precursor, similar to NMN. Available as a supplement (Tru Niagen, Elysium Basis). Has more human safety data than NMN but similar uncertainty about efficacy.

Using an FDA-approved medication for a purpose other than its official indication. Legal and common in medicine, doctors can prescribe metformin "off-label" for longevity even though it's approved for diabetes.

A short chain of amino acids (typically 2-50). Peptides are smaller than proteins and can have various biological functions. Many are used in research and some (like semaglutide) are FDA-approved medications.

An mTOR inhibitor originally used as an immunosuppressant. Shows the most consistent lifespan extension in animal studies of any compound tested. Being explored in humans at low, intermittent doses for potential anti-aging effects.

The process of adding liquid (typically bacteriostatic water) to a lyophilized (freeze-dried) peptide to prepare it for injection. Proper reconstitution and storage are critical for peptide stability and safety.

A GLP-1 receptor agonist sold as Ozempic (for diabetes) and Wegovy (for weight loss). The first highly effective pharmaceutical weight loss treatment, with average 15% body weight reduction in clinical trials.

Aged, dysfunctional cells that stop dividing but don't die. They accumulate with age and secrete inflammatory factors that damage surrounding tissue. Senolytics are compounds designed to selectively eliminate them.

Compounds that selectively kill senescent cells. The most studied combination is dasatinib + quercetin (D+Q). Human trials are ongoing but evidence is preliminary.

An injection into the fatty tissue just below the skin (not into muscle or vein). Most peptides and GLP-1 medications are administered this way, typically in the abdomen, thigh, or upper arm.

Thymosin Beta-4, a naturally occurring peptide involved in tissue repair. Used primarily for injury recovery and healing, though most evidence comes from animal studies.

A dual GLP-1/GIP receptor agonist sold as Mounjaro (for diabetes) and Zepbound (for weight loss). Shows even greater weight loss than semaglutide in trials, averaging 20%+ body weight reduction.

Gradually increasing medication dosage over time to minimize side effects and allow the body to adjust. GLP-1 medications like semaglutide require careful titration over several months.

Medical treatment to restore testosterone levels in men with clinically low testosterone. Can be administered via injections, gels, patches, or pellets.