REGULATORYRFK Jr.: 14 peptides returning to Category 1 — FDA advisory committee July 2026TRENDINGHexarelin: ↑↑ Surging ��� Trends score 100 as of May 2026UPDATESemaglutide and tirzepatide compounding ended — shortage resolved Feb/May 2025REGULATORYBPC-157, TB-500, thymosin alpha-1, CJC-1295, ipamorelin: expected Category 1 reclassification pendingEVENTpep-talk con ��� First US Peptide Convention · August 2026 · Anaheim CAFDAFDA advisory committee meetings scheduled: late July 2026REGULATORYRFK Jr.: 14 peptides returning to Category 1 — FDA advisory committee July 2026TRENDINGHexarelin: ↑↑ Surging ��� Trends score 100 as of May 2026UPDATESemaglutide and tirzepatide compounding ended — shortage resolved Feb/May 2025REGULATORYBPC-157, TB-500, thymosin alpha-1, CJC-1295, ipamorelin: expected Category 1 reclassification pendingEVENTpep-talk con ��� First US Peptide Convention · August 2026 · Anaheim CAFDAFDA advisory committee meetings scheduled: late July 2026

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Peptide Library

MGF

Mechano Growth Factor / IGF-1Ec

Growth Factors

Mechano Growth Factor (MGF) is a splice variant of the IGF-1 gene (specifically the IGF-1Ec isoform in humans) that is expressed locally in muscle tissue in response to mechanical stress such as resistance exercise or injury. Unlike systemic IGF-1, MGF acts in an autocrine/paracrine manner to activate muscle satellite cells and initiate local repair processes. It is a research peptide studied for its role in muscle regeneration, injury recovery, and exercise-induced adaptation.

Mechanism of Action

Splice variant of IGF-1 produced in response to mechanical loading (exercise). Activates satellite cells in muscle tissue, promoting myoblast proliferation and muscle repair. Acts locally at the site of muscle damage before being converted to systemic IGF-1.

Research Protocols

For research purposes only. Not medical advice.

Research protocols use 100-200mcg per injection, administered intramuscularly into the target muscle immediately post-workout. Very short half-life requires local administration. Cycles of 4-6 weeks.

Research Notes

Clinical Research Status

MGF remains a preclinical research compound with no formal clinical trials conducted in humans for any therapeutic indication. Academic research has focused on understanding its role in exercise-induced muscle repair and satellite cell activation using in vitro and animal models. The synthetic peptide form used in research represents the C-terminal 24-amino acid sequence unique to the MGF splice variant (the E-domain peptide).

Key Published Findings

Research demonstrates that MGF expression peaks 24-72 hours after muscle damage, preceding the systemic IGF-1Ea isoform expression that follows later in the repair process. In vitro studies show the MGF E-domain peptide activates quiescent satellite cells, promoting their proliferation without immediate differentiation, effectively expanding the myogenic progenitor pool. Animal studies indicate local MGF injection can enhance muscle regeneration after injury, with up to 25% greater muscle mass recovery compared to controls.

Safety Profile

No formal human safety data exists for synthetic MGF peptide administration. The short half-life (minutes when unmodified) limits both efficacy and potential for adverse effects from systemic exposure. Theoretical concerns include uncontrolled satellite cell proliferation and potential interference with normal muscle repair signaling cascades. The extremely rapid degradation of unPEGylated MGF in plasma raises questions about whether injected peptide reaches target tissues at meaningful concentrations.

Comparison to Related Compounds

Unlike IGF-1 LR3 which has potent systemic anabolic effects, MGF is designed for local autocrine/paracrine muscle repair signaling with minimal systemic activity. PEG-MGF extends the half-life through PEGylation, converting it from a locally-acting to a more systemically-active peptide. Compared to full-length IGF-1, MGF specifically targets satellite cell activation (proliferation phase) rather than the differentiation and hypertrophy phases driven by IGF-1Ea.

Community Observations

Researchers note that unmodified MGF's extremely short half-life of 5-7 minutes in plasma makes systemic injection largely impractical for achieving meaningful local muscle concentrations. Some protocols suggest intramuscular injection directly into target muscles immediately post-exercise to approximate the natural local expression pattern. The distinction between MGF's satellite cell activating role and IGF-1's downstream hypertrophy signaling represents an important conceptual framework for understanding muscle repair biology.

Half-Life

~5-7 minutes

Reconstitution

Bacteriostatic water (BAC)

Storage

Lyophilized

Refrigerate 2-8C up to 12 months.

Reconstituted

Refrigerate 2-8C. Use within 7 days.

US Legal Status

Research chemical (not FDA-approved)

Also Known As

Mechano Growth FactorIGF-1Ec

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