NAD+ vs Thymalin

NAD+ is a coenzyme central to cellular energy metabolism, serving as an electron carrier in glycolysis, the citric acid cycle, and oxidative phosphorylation. It is also a required substrate for sirtuins (SIRT1–7) and PARP enzymes, which regulate DNA repair, gene expression, and mitochondrial biogenesis. NAD+ levels decline measurably with age; IV or subcutaneous delivery aims to restore intracellular pools more directly than oral precursors such as NMN or NR.

NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every cell, central to energy production, DNA repair, and sirtuin activation. While not a peptide in the traditional sense, it is widely administered by functional medicine and longevity providers via intravenous infusion or subcutaneous injection. Research interest centres on its role in mitochondrial health, cellular resilience, and neurological function as NAD+ levels decline with age. NAD+ IV therapy: intravenous NAD+ infusion is the administration route that has attracted the most clinical interest, particularly in longevity and functional medicine contexts. IV NAD+ therapy delivers the compound directly into the bloodstream, bypassing digestive absorption — a route considered relevant given that oral NAD+ precursors (NMN, NR) have variable bioavailability. NAD+ IV therapy cost typically ranges from $200–$1,000 per session depending on the clinic, infusion volume, and geographic market; treatment frequency in clinical settings commonly ranges from weekly to monthly maintenance infusions following an initial loading protocol. NAD+ IV therapy clinics operate across major US markets including Houston, Los Angeles, New York, and Las Vegas. For those researching where to find NAD+ IV therapy providers, PeptideBase maintains a directory of verified clinics and telehealth platforms offering NAD+ protocols.

Thymic peptide bioregulator; restores thymic function and T-cell production; modulates cytokine balance; shown to extend lifespan in animal models

Thymalin is a polypeptide preparation and Khavinson-class bioregulator derived from thymic tissue, proposed to restore age-related immune dysfunction associated with thymic involution by supplying thymic hormonal signals that support T-lymphocyte differentiation, immune homeostasis, and immunological reserve in elderly subjects. As a thymic bioregulator, thymalin is proposed to modulate gene expression in aging lymphoid cells through peptide-chromatin interactions and to support thymopoiesis and T-cell maturation in subjects whose endogenous thymic output has declined with age-associated involution. Published observational research from the Khavinson laboratory documented that long-term supplementation with thymalin and related thymic and pineal peptides was associated with significantly reduced all-cause mortality in elderly cohorts over extended follow-up, and earlier work reported geroprotective effects of thymalin and epithalamin in Russian geriatric research populations. Thymalin is not FDA-approved; it is available as a clinical preparation in Russia, where it has regulatory approval for immune support in elderly patients, and its evidence base derives from Russian-origin observational and preclinical studies with limited independent replication by international standards. Thymalin benefits investigated in preclinical and clinical research include immune system restoration in aged subjects, improved T-lymphocyte counts and function, modulation of cytokine balance toward anti-inflammatory profiles, and partial reversal of age-associated thymic involution. Long-term studies in aged animal models have documented lifespan extension with thymalin administration, and observational research in elderly human cohorts using thymic peptide preparations has associated treatment with reduced all-cause mortality over multiyear follow-up periods — findings published in Russian medical literature. As a thymic bioregulator, thymalin is proposed to work by restoring the hormonal output of the aging thymus rather than by immunosuppression or direct cytokine administration, distinguishing it from synthetic immunomodulatory drugs. Research interest also includes thymalin for age-related infections susceptibility, autoimmune regulation, and overall immune resilience as part of longevity-focused bioregulator protocols.