Follistatin (FLGR242)

Follistatin, often referenced in research contexts as FLGR242 (a specific recombinant variant like Follistatin-344 or a pegylated/AA form), is a naturally occurring glycoprotein that acts as a potent myostatin inhibitor. Myostatin is a protein that limits muscle growth, so follistatin promotes hypertrophy (muscle growth) by binding and neutralizing it. It’s popular in bodybuilding and anti-aging research for its potential to enhance lean mass, strength, and recovery. The “10mg” refers to a common lyophilized vial size for reconstitution.

Key Properties & Mechanism

• Molecular Target: Inhibits myostatin (GDF-8) and other TGF-β family members (e.g., activin), unlocking satellite cell proliferation and muscle fiber hyperplasia.
• Half-Life: Native form ~2-4 hours; pegylated/FLGR242 variants extend to 24-48+ hours for less frequent dosing.
• Purity/Origin: Typically produced via E. coli or yeast (FLGR242 is often a 315-amino-acid construct with high bioactivity >95%).

Evidence:

• Studies (e.g., PNAS 2007, Lee et al.): Follistatin (FLGR242) (10mg) overexpression in mice increased muscle mass by 2-3x without steroids.
• Human trials limited (phase I/II for neuromuscular diseases like Becker MD), but rodent/primate data shows 20-50% lean mass gains in 4-12 weeks (JCI 2010).
• Anecdotal: Bodybuilders report 5-15lbs lean gains/cycle, synergizes with SARMs/IGF-1.

Reconstitution & Dosing Protocol (Research Use)

Supplies Needed:

Reconstitution (10mg vial):

1. Add 2mL BAC → 5mg/mL (500mcg per 0.1mL).
2. Gently swirl (no shake) until clear.
3. Store refrigerated (stable 4°C for 30 days; freeze aliquots -20°C for 6+ months).

Standard Research Dosing (not medical advice; experimental):

• Injection: SubQ preferred (less pain); rotate sites.
• Stacking: Pairs with GHRP-6, CJC-1295, or MK-677 for GH synergy (myostatin + IGF axis).
• On-Cycle Support: Monitor liver/kidney (ALT/AST via bloodwork); hydrate heavily.

Sides & Risk Mitigation

No estrogenic/androgenic activity; suppresses natural myostatin long-term (up to 6 months post-cycle).

Sourcing & Legality

• Research-Only: Not FDA-approved for human use ( Schedule? No, peptide gray area). Buy from Sino Research Peptide Manufacturer
  (e.g., 99%+ HPLC/MS verified).
• Cost: $150-300/10mg vial.
• Storage: Lyophilized RT stable; reconstituted fridge.

Pro Tip: Run bloods pre/post (myostatin levels via ELISA if available; expect 50-80% drop). For max effect, combine with resistance training + 1.5g protein/lb BW.

If this is for a specific protocol or stack, drop details for optimization. Research responsibly! 🧪💪