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GDF-8 (Myostatin Inhibitor)

Growth Factors & Muscle Building

GDF-8, also known as Myostatin, is a negative regulator of muscle growth. Inhibiting GDF-8 through peptide analogs or propeptides has shown promise in increasing muscle mass and preventing muscle wasting in conditions like muscular dystrophy and cachexia. Though animal studies are promising, translation to human therapies has been limited by safety and delivery challenges.

Reconstitute
2 mL BAC + 2mg vial
10 mcg/unit
Daily Range
50–200 mcg Subcutaneous (SQ)
1-2x weekly
Standard Dose
100 mcg
Cycle
4–8 weeks
then reassess
GDF-8MyostatinMyostatin inhibitormuscle growthmuscle wasting

Dosing & Reconstitution Guide

In animal studies, anti-myostatin antibodies and peptides are dosed variably depending on compound structure and delivery method. These findings do not apply to human use without further clinical validation.

Standard / Gradual Approach

2mg Vialstandard
PhaseDoseVolume
Weeks 1–250 mcg SQ 1x/week5 units (0.05 mL)
Weeks 3–6100 mcg SQ 1–2x/week10 units (0.10 mL)
Weeks 7–12200 mcg SQ 2x/week20 units (0.20 mL)

Protocol Summary

Subcutaneous (SQ): 1-2x weekly · Dose range 50200 mcg with gradual titration
Cycle Length: 4–8 weeks typical; reassess before extending

Frequency & Cycling

SubQ Injection

Administer 1–2x weekly for up to 12 weeks. Cycle off for 4–8 weeks to evaluate physiological response and minimize hormonal desensitization.

🧪 Quick Start

Vial Size
2 mg
BAC Water
2 mL
Concentration
1000 mcg/unit

Potential Benefits & Use Cases

Myostatin inhibitors are investigational compounds not approved for human use. The content on this page is intended for educational and research purposes only.
Increased muscle mass observed in myostatin knockout mice
Research shows enhanced recovery and hypertrophy in animal models
Investigated for muscle-wasting conditions in early-stage trials
Explored for its role in strength and lean body mass modulation
Clinical data Strong preclinical Limited data

Mechanism of Action

Inhibits GDF-8 (myostatin) signaling pathway
Blocks negative regulation of muscle growth
Prevents activation of Smad2/3 signaling involved in muscle catabolism

Lifestyle & Optimization

timing

Consistent dosing schedule aligned with training.

diet

Protein intake of 1.6–2.2 g/kg/day. Creatine supplementation may complement effects.

exercise

Progressive overload resistance training for maximum muscle growth stimulus.

sleep

Adequate sleep and recovery between training sessions.

Side Effects & Safety

Common Side Effects

Injection site irritation or discomfort

Contraindications & Warnings

Possible systemic endocrine effects including suppression of reproductive hormones

Long-Term Safety Data

Unknown long-term effects on myostatin-regulated homeostasis and cardiac muscle

🧮 Dose Calculator

Concentration
10.0
mcg/unit
Draw Volume
50
units (0.500 mL)
For a 500 mcg dose, draw 50 units on a U-100 insulin syringe
🧬

Bioavailability & Absorption

SubQ Injection
High when administered via SubQ injection; most studies use this route for targeted muscle growth
Oral Administration
Not bioavailable orally due to proteolytic degradation
Half-Life
Exact duration unknown; varies by formulation
Degradation
Metabolized by proteolytic enzymes and tissue peptidases
Tissue Specificity
Predominantly acts on skeletal muscle satellite cells
⚗️

Peptide Details

Molecular Weight
25000
Formula
C101H170N48O31S8
Sequence
Human GDF-8 (Myostatin) Propeptide
⚖️

Legal Status & Regulatory

RegionStatus
FDANot Approved
EUNot Approved
AustraliaNot Approved
CanadaNot Approved

Storage Instructions

Lyophilized (Powder)
Store at -20°C for long-term. Stable at 2–8°C for up to 6 months.
Reconstituted (Mixed)
Refrigerate at 2–8°C. Use within 2–3 weeks. Avoid freeze-thaw.