Growth hormone secretagogue

MGF (mechano growth factor)

A muscle-derived IGF-1 variant sold for local repair; every claim rests on animal and cell work.

Anecdotal evidenceNot approvedAdd to compare

What it is

Mechano growth factor (MGF) is a short splice variant of IGF-1 that muscle produces after mechanical damage. A PEGylated version, PEG-MGF, is sold as a research peptide intended to last longer in the body. Neither is an approved medicine, human data are essentially absent, and it is prohibited in sport.

How it works

1
MGF is a splice variant of IGF-1 produced in muscle after mechanical damage.
2
In laboratory models it activates muscle stem cells and drives local repair.
3
The PEGylated form is designed to survive enzyme breakdown long enough to act.
4
Most effects described are local to the injected muscle, which is why users inject near the injury.
5
These mechanisms have not been demonstrated in controlled human studies.

What it's studied for

Muscle repair and hypertrophy in animal and cell models

Satellite cell activation research

Injury-recovery claims in sports settings

No human trials exist

Reported and studied effects

Local muscle growth in animal models
Increased protein synthesis in laboratory tissue
Reported faster injury recovery in user accounts
Hypoglycaemia risk, as with the IGF-1 family

Research protocol notes

Research context only

Research context only — no human protocol exists. Laboratory work used microgram doses in cell and animal models. Schedules of 200–400 micrograms injected into a specific muscle after training come entirely from community practice, and there is no published human safety or efficacy data.

These figures are described so you can understand what researchers did. They are not a dose, a schedule, or a suggestion — and they are not a substitute for a doctor.

Possible side effects and contraindications

Safety profile

Possible side effects

Injection-site pain and swelling
Hypoglycaemia
Joint and jaw pain, as with the IGF-1 class
Possible promotion of existing cancers
Long-term safety unknown

Contraindications and cautions

Any history of cancer
Pregnancy, breastfeeding and childhood
Retinopathy or diabetes
Prohibited in competitive sport

A side-effect list is never complete, and these are not the only situations that warrant caution. Anything unexpected, or anything you are unsure about, should be discussed with a doctor before use.

Evidence assessment

Anecdotal evidenceNo controlled human data

No controlled human data

There are no controlled human studies of MGF; all available data come from cell and animal experiments plus user reports.

References

References link to published literature, regulator pages or literature indexes. Where a link points to a search, it collects the peer-reviewed work on that molecule rather than a single study.

Compare MGF (mechano growth factor) with another peptide →

Related peptides

Other entries in Growth hormone secretagogue.

All Growth hormone secretagogue peptides →

Growth hormone secretagogue

CJC-1295

A modified growth-hormone-releasing hormone analogue whose albumin binding gives it an unusually long action. Studied in small human trials; not an approved medicine.

Limited evidenceNot approved

Growth hormone secretagogue

CJC-1295 (no DAC) + Ipamorelin blend

The classic growth-hormone stack in one vial: a GHRH fragment with a secretagogue, unapproved and prohibited in sport.

Anecdotal evidenceNot approved

Growth hormone secretagogue

CJC-1295 (no DAC) / mod GRF 1-29

The short-acting sister of CJC-1295: a GHRH fragment that produces brief growth-hormone pulses instead of sustained elevation.

Limited evidenceNot approved