Side-by-side · Research reference

GLP-1 (7-37)vsIGF-DES

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

AHuman-MechanisticHUMAN-REVIEWED16/43 cited

BAnimal-StrongHUMAN-REVIEWED8/60 cited

GLP-1 (7-37)

Incretin Hormone · Native Peptide

~2 minHalf-lifeAlavi 2021 Ding 2017

3297.7 DaMolecular weightAlavi 2021

1922Discovery year

Research use only · IV/SC in experimental settings

IGF-DES

IGF-1 Analogue · Truncated N-Terminal

~10×Potency vs IGF-1

ReducedIGFBP binding

ResearchStatus

Injection (local or systemic) · Research protocols onlyBredehöft 2008

01Mechanism of Action

Parameter

GLP-1 (7-37)

IGF-DES

Primary target

GLP-1 receptor (class B GPCR)Koole 2015

IGF-1 receptor (IGF1R)Shields 2007

Pathway

GLP-1R activation → cAMP production → PKA signaling → insulin secretion (pancreatic β-cells)Lu 2025 Koole 2015

IGF1R activation → PI3K/Akt & MAPK signaling → protein synthesis, proliferation

Downstream effect

Glucose-dependent insulin release, glucagon suppression, delayed gastric emptying, reduced food intakeLu 2025 Ding 2017

Enhanced muscle protein synthesis, myoblast differentiation, reduced apoptosis, cell proliferation

Feedback intact?

Yes — physiological secretion and degradation preserved

Unknown — no human endocrine feedback data

Origin

Endogenous peptide cleaved from proglucagon in intestinal L cells; secreted postprandially

Synthetic truncation of native IGF-1 — removal of N-terminal Gly-Pro-Glu tripeptideBredehöft 2008

Antibody development

—

02Dosage Protocols

Parameter

GLP-1 (7-37)

IGF-DES

Clinical use

None — native GLP-1 not used therapeutically

Engineered analogues (semaglutide, liraglutide) used clinically.Friedman 2024

—

Research dosing

Variable — 0.1–10 nmol/kg in animal models

Used as reference standard for analogue comparison.

—

Half-life

~2 minutes (plasma)Alavi 2021 Ding 2017

Requires continuous infusion for sustained effect.

Shorter than IGF-1 due to reduced IGFBP binding

Rapid tissue uptake, limited systemic circulation.

Modified analogues

t½ extended to 13 h (liraglutide), 165 h (semaglutide)

Via DPP-4 resistance + fatty acid acylation.

—

Research dose range

—

10–100 ng/mL (in vitro); μg doses (animal models)

Highly context-dependent; no standardized human protocol.

Route

—

Subcutaneous or intramuscular (local injection favored)

Local delivery maximizes tissue-specific uptake.

Frequency

—

Variable — daily to multiple times daily in research

Evidence basis

—

Animal models + in vitro only

Human data

—

None — no clinical trials

03Metabolic / Fat Loss Evidence

Parameter

GLP-1 (7-37)

IGF-DES

Mechanism

GLP-1R activation in hypothalamic satiety centers (arcuate nucleus) reduces food intakeLu 2025

Effect demonstrated with long-acting analogues (liraglutide).Lu 2025

—

Native GLP-1 efficacy

Minimal — rapid degradation prevents sustained appetite suppression

—

Gastric emptying

Delayed in animal models, contributing to satiety

—

Body weight impact

Not observed with native GLP-1 — requires analogue formulations

—

Primary mechanism

—

Indirect via muscle hypertrophy → metabolic rate elevation

Direct lipolysis

—

Minimal evidence — IGF-1 axis primarily anabolic, not lipolytic

Prostate model

—

Inhibited BPH cell proliferation when combined with vitamin D3 analogueCrescioli 2002

Context-specific anti-proliferative effect, not fat loss.

04Side Effects & Safety

Parameter

GLP-1 (7-37)

IGF-DES

Native GLP-1

Well-tolerated in research settings; no prolonged exposure data

—

Hypoglycemia risk

Low — insulin secretion is glucose-dependent

Theoretical — IGF-1 axis enhances glucose uptake

Analogue side effects

Nausea, vomiting, diarrhea (GLP-1R agonists)

Not applicable to native GLP-1 due to non-therapeutic use.

—

GLP-1 resistance

High glucose-induced PKCβ overexpression may reduce GLP-1 responsiveness in endothelial cellsPujadas 2016

—

Mitogenic risk

—

Chronic IGF-1 receptor activation may promote cell proliferation, potential tumor growthCrescioli 2002

Injection site reaction

—

Expected — erythema, irritation, local swelling

Edema / Fluid retention

—

Possible via sodium retention (IGF-1 axis effect)

Human safety data

—

Absent — no human trials, all effects theoretical or extrapolated

Unknown long-term effects

—

No chronic dosing studies in humans; endocrine, metabolic consequences unknown

Absolute Contraindications

GLP-1 (7-37)

—

IGF-DES

·Active malignancy or history of cancer (mitogenic risk)
·Pregnancy / lactation (no safety data)
·Hypoglycemia disorders

Relative Contraindications

GLP-1 (7-37)

—

IGF-DES

·Diabetes mellitus (unpredictable glucose effects)
·Renal or hepatic impairment (clearance unknown)
·Edema-prone conditions (heart failure, nephrotic syndrome)

05Administration Protocol

Parameter

GLP-1 (7-37)

IGF-DES

1. Research use only

Native GLP-1(7-37) is not formulated for therapeutic use. Administered IV or SC in experimental protocols to study GLP-1R pharmacology and as reference standard for analogue development.

Des(1-3)IGF-1 has no approved human protocol. All administration details are derived from animal or in vitro research and should not be construed as medical guidance.

2. Storage

Lyophilised peptide stored at -20°C or below. Reconstituted solutions should be prepared fresh and used immediately due to rapid degradation.

Sterile water or bacteriostatic water per research protocol. Gently swirl; do not shake. Store reconstituted peptide at 2–8 °C.

3. Clinical alternatives

For therapeutic GLP-1R activation, use FDA-approved long-acting analogues: semaglutide (once weekly), liraglutide (once daily), dulaglutide (once weekly), or exenatide (twice daily or once weekly).

Subcutaneous (abdomen, thigh) or intramuscular (deltoid, vastus lateralis). Local injection to target tissue (e.g., muscle group) may enhance regional uptake.

4. Timing

—

Frequency and timing vary by research design. Post-exercise or fasted state may theoretically enhance muscle uptake.

5. Needle gauge

—

27–31G insulin syringe for subcutaneous; 25–27G for intramuscular.

6. Monitoring

—

Glucose monitoring essential (hypoglycemia risk). No established IGF-1 or safety labs for human use.

06Stack Synergy

GLP-1 (7-37)

— no documented stacks

IGF-DES

+ BPC-157

Moderate

View BPC-157 →

Des(1-3)IGF-1 promotes myoblast differentiation and protein synthesis, while BPC-157 enhances tissue repair, angiogenesis, and collagen synthesis. Both act on distinct pathways (IGF1R vs gastric pentadecapeptide mechanisms) to support muscle recovery and connective tissue integrity. Synergy is mechanistic but lacks direct co-administration studies.

Des(1-3)IGF-1: Research dose post-workout (local IM)
BPC-157: 250–500 mcg SQ, daily or twice daily
Frequency: Daily or per research protocol
Primary benefit: Accelerated muscle repair, enhanced hypertrophy, connective tissue support

+ TB-500

Moderate

View TB-500 →

TB-500 (Thymosin Beta-4 fragment) promotes cell migration, angiogenesis, and wound healing via actin regulation. Des(1-3)IGF-1 drives protein synthesis and myoblast proliferation. Combined, these peptides may synergistically enhance muscle recovery, repair, and hypertrophy through complementary anabolic and regenerative pathways. No direct human co-administration data.

Des(1-3)IGF-1: Research dose post-workout (local IM)
TB-500: 2–5 mg SQ, 2× weekly
Frequency: Per research cycle
Primary benefit: Muscle hypertrophy, injury recovery, vascular support