Apelin-13 — Plexus Peptide Reference

Complete Research Guide

Open each section for the available evidence. Gaps are stated rather than inferred.

Overview

Apelin-13 is listed as cardiometabolic / exerkine (apj receptor agonist).

•Cardiovascular function research
•Muscle aging (sarcopenia) research
•Insulin sensitivity and glucose uptake research
•Fluid balance (vasopressin counter-regulation)
•Blood-vessel growth and maturation
•Mitochondrial biogenesis in muscle
•Kidney protection research

Regulatory status: Not FDA-approved for any use. Investigational research compound; sold as a research chemical. Not listed by name on the WADA prohibited list, but may fall under its general non-approved substances clause..

Structure & Properties

Compound: Apelin-13; also known as Apelin 13, [Pyr1]-Apelin-13, Pyr-apelin-13, APJ agonist peptide, APLNR ligand.

Pharmacologic class: Cardiometabolic / Exerkine (APJ receptor agonist).

Known delivery routes: IV Infusion (clinical research only), Subcutaneous (unstudied).

Sequence, molecular weight, salt form, and excipient details are formulation-specific and are not listed unless verified by a manufacturer or laboratory COA.

How It Works

A 13-amino-acid fragment of the endogenous hormone apelin and the dominant form in human plasma (as the pyroglutamate form, [Pyr1]-apelin-13). It activates the APJ receptor (APLNR), a G-protein-coupled receptor in heart, blood vessels, muscle, fat and kidney. Effects include nitric-oxide–dependent vasodilation, increased heart contractility without raising heart rate, AMPK activation that boosts glucose uptake and mitochondrial biogenesis in muscle, and suppression of vasopressin release. It is cleared within minutes in blood, largely by ACE2 and neprilysin.

•Increased cardiac output and lower vascular resistance in short human infusion studies
•Improves glucose uptake and insulin sensitivity in animal models
•Reversed age-related muscle loss and improved muscle function in aged mice
•Supports mitochondrial biogenesis in skeletal muscle (animal data)
•Counteracts vasopressin, promoting water excretion (animal data)
•Protective effects in animal models of kidney and heart injury

Human Research

Evidence grade: Clinical RCT (Limited)

Clinical RCT (Limited). Small human mechanistic studies (healthy volunteers and chronic heart failure patients) show short-term vasodilation and increased cardiac output. Extensive animal data in heart failure, insulin resistance, sarcopenia, kidney injury and angiogenesis. No long-term human safety or efficacy trials; longer-acting APJ agonists are in early drug development..

Laboratory Research

Small human mechanistic studies (healthy volunteers and chronic heart failure patients) show short-term vasodilation and increased cardiac output. Extensive animal data in heart failure, insulin resistance, sarcopenia, kidney injury and angiogenesis. No long-term human safety or efficacy trials; longer-acting APJ agonists are in early drug development.

Preclinical findings describe biological plausibility, not proven benefit in people. Animal and laboratory doses do not translate directly to human use.

Processing & Interactions

Timing and exposure

No established schedule. Human studies gave short supervised IV infusions only; the native peptide is cleared within minutes.

Potential interactions and combinations to avoid

•Blood-pressure–lowering drugs or nitrates — additive hypotension
•Active or suspected cancer — pro-angiogenic signaling
•ACE2-modulating or neprilysin-inhibiting drugs (e.g., sacubitril) — may alter apelin breakdown

Absorption, half-life, metabolism, and clearance can vary by formulation and route. Use prescribing information when an approved product exists.

Safety & Precautions

Known or reported risks

•Drop in blood pressure and reflex symptoms (flushing, light-headedness)
•Pro-angiogenic activity — promotes tumor blood-vessel growth in animal studies
•Extremely short half-life makes research-market injection effects unpredictable
•No long-term human safety data
•Research-chemical supply — purity, sterility and identity unverified

Contraindications

•Active cancer or history of cancer (pro-angiogenic signaling)
•Low blood pressure or use of blood-pressure–lowering medications
•Pregnancy or breastfeeding
•Proliferative diabetic retinopathy or other abnormal blood-vessel growth disorders
•Under 18 years of age
•Bleeding disorders or anticoagulant therapy without physician guidance (injection-site haematoma)
•Active skin infection, cellulitis, or lipohypertrophy at intended injection sites
•Inability to maintain sterile technique or safe sharps disposal
•Not FDA-approved for human therapeutic use — no verified purity, sterility, or potency standards
•Immunocompromised or transplant patients (unverified sterility and immunogenicity risk)
•Concurrent participation in drug-tested sport (WADA prohibited or non-cleared substance)
•Known hypersensitivity or prior reaction to this compound or any excipient/diluent
•Pregnancy, attempting conception, or breastfeeding unless prescribed and monitored by a physician
•Children and adolescents with open growth plates (unless under specialist endocrine care)
•Active or recently treated malignancy without oncology clearance
•Use without a confirmed diagnosis, baseline labs, and licensed clinical supervision

Unknown long-term toxicity should be assumed where controlled human data are limited. Seek urgent care for a severe or unexpected reaction.

Administration & Studied Formulations

Reference range: No established human dose. Human studies used brief intravenous or intra-arterial infusions only (e.g., 30–300 nmol/min for minutes); research-market subcutaneous dosing is unstudied.

Frequency: Not established — native peptide half-life is under ~5 minutes

Cycling: No evidence-based cycle exists. Human data are limited to single-session infusions lasting minutes to hours; any repeated use is outside studied conditions.

IV Infusion

Clinical research only — short supervised infusions with blood-pressure monitoring.

IV or intra-arterial infusion in a research setting. Clinician-only. No validated self-administration route or dose.

Subcutaneous research-market use has no human pharmacokinetic data; the native peptide is cleared within minutes.

Dosing information is educational context, not a personal recommendation. Approved products must follow their label and prescriber instructions.

Applications & Related Therapies

Potentially complementary measures

•Regular aerobic and resistance exercise — naturally raises circulating apelin
•Clinician-guided cardiometabolic care

Clinical use should account for diagnosis, approved alternatives, nutrition, activity, sleep, rehabilitation, current medicines, and appropriate monitoring.

Investigational only. Evidence is mainly mechanistic human infusion studies plus animal research; no human dosing protocol exists.

Cases, Considerations & Ethics

Decision framework: establish the clinical goal, confirm evidence quality and legal status, screen contraindications and interactions, compare approved alternatives, define monitoring and stopping criteria, and use shared decision-making with a licensed clinician.

Case evidence: individual reports cannot establish safety or effectiveness and should not outweigh controlled trials.

Ethics: informed consent should distinguish established care from experimental use, disclose uncertainty and cost, avoid overstated claims, and never substitute research products for medically necessary care.

What is Apelin-13?

In plain words

Apelin-13 is a short piece of a hormone the body naturally makes. It sends signals that can widen blood vessels, strengthen heart contractions and help muscles take in sugar, but the body breaks it down within minutes. Researchers study it for heart and blood-vessel function, age-related muscle loss and blood sugar control. Human trial evidence is limited, it can lower blood pressure, and there are no long-term human safety data.

Technical definition

Apelin-13 is a 13-amino-acid peptide fragment of the endogenous hormone apelin; its pyroglutamate form, [Pyr1]-apelin-13, is the dominant form in human plasma. It activates APJ (APLNR), a G-protein-coupled receptor in cardiovascular, muscle, fat and kidney tissues, promoting nitric-oxide–dependent vasodilation, increased cardiac contractility without increased heart rate, AMPK-mediated muscle glucose uptake and mitochondrial biogenesis, and suppression of vasopressin release; it is cleared within minutes, largely by ACE2 and neprilysin. It is an investigational research compound, not FDA-approved for any use; although not named on the WADA prohibited list, it may fall under the general non-approved substances clause.

Function

Primary

Cardiovascular function research · Muscle aging (sarcopenia) research · Insulin sensitivity and glucose uptake research

Secondary

Fluid balance (vasopressin counter-regulation) · Blood-vessel growth and maturation · Mitochondrial biogenesis in muscle · Kidney protection research

Mechanism

A 13-amino-acid fragment of the endogenous hormone apelin and the dominant form in human plasma (as the pyroglutamate form, [Pyr1]-apelin-13). It activates the APJ receptor (APLNR), a G-protein-coupled receptor in heart, blood vessels, muscle, fat and kidney. Effects include nitric-oxide–dependent vasodilation, increased heart contractility without raising heart rate, AMPK activation that boosts glucose uptake and mitochondrial biogenesis in muscle, and suppression of vasopressin release. It is cleared within minutes in blood, largely by ACE2 and neprilysin.

Evidence

Clinical RCT (Limited)

Research

Small human mechanistic studies (healthy volunteers and chronic heart failure patients) show short-term vasodilation and increased cardiac output. Extensive animal data in heart failure, insulin resistance, sarcopenia, kidney injury and angiogenesis. No long-term human safety or efficacy trials; longer-acting APJ agonists are in early drug development.

Dosing

Range

No established human dose. Human studies used brief intravenous or intra-arterial infusions only (e.g., 30–300 nmol/min for minutes); research-market subcutaneous dosing is unstudied.

Frequency

Not established — native peptide half-life is under ~5 minutes

Route

IV Infusion (clinical research only) · Subcutaneous (unstudied)

Recommended Time of Day

Not established — human studies used brief supervised infusions; no time-of-day data.

See “Timing & Interactions” below for full fasted/fed circumstances, what to avoid combining, and what pairs well.

Administration & Technique

IV Infusion

Clinical research only — short supervised infusions with blood-pressure monitoring.

DeviceIV or intra-arterial infusion in a research setting.

TechniqueClinician-only. No validated self-administration route or dose.

Subcutaneous research-market use has no human pharmacokinetic data; the native peptide is cleared within minutes.

Injection & Application Sites

Front

Back

IV Infusion

IV — clinician only — Antecubital vein or central line. Not for home administration.

Diagram is a general illustration, not a medical instruction. Rotate sites every injection, keep 1 in (2.5 cm) between recent sites, and avoid scars, moles, bruises and the navel area.

Cycling

No evidence-based cycle exists. Human data are limited to single-session infusions lasting minutes to hours; any repeated use is outside studied conditions.

Timing & Interactions

When to take

No established schedule. Human studies gave short supervised IV infusions only; the native peptide is cleared within minutes.

Do not combine with

·Blood-pressure–lowering drugs or nitrates — additive hypotension
·Active or suspected cancer — pro-angiogenic signaling
·ACE2-modulating or neprilysin-inhibiting drugs (e.g., sacubitril) — may alter apelin breakdown

Complements

·Regular aerobic and resistance exercise — naturally raises circulating apelin
·Clinician-guided cardiometabolic care

Notes

Investigational only. Evidence is mainly mechanistic human infusion studies plus animal research; no human dosing protocol exists.

Storage & Reconstitution

Powder (Pre-Reconstitution)

Lyophilized: freeze at –20°C, protected from light and moisture.

After Reconstitution

Refrigerate 2–8°C and use promptly; apelin peptides degrade quickly in solution.

Notes

Unmodified Apelin-13 is less stable than the pyroglutamate form ([Pyr1]-apelin-13).

Full BAC water & reconstitution guide →How to read a COA →

Reconstitution Calculator

Peptide in vial (mg)

BAC water added (mL)

Desired dose (mcg)

Concentration

2.50 mg/mL

Volume per dose

0.100 mL

Insulin syringe

10.0 units (U-100)

1 mL = 100 units on a standard U-100 insulin syringe. Draw to the nearest 0.5 unit and confirm dosing with a clinician before injection.

Your Notes

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Benefits

·Increased cardiac output and lower vascular resistance in short human infusion studies
·Improves glucose uptake and insulin sensitivity in animal models
·Reversed age-related muscle loss and improved muscle function in aged mice
·Supports mitochondrial biogenesis in skeletal muscle (animal data)
·Counteracts vasopressin, promoting water excretion (animal data)
·Protective effects in animal models of kidney and heart injury

Risks

·Drop in blood pressure and reflex symptoms (flushing, light-headedness)
·Pro-angiogenic activity — promotes tumor blood-vessel growth in animal studies
·Extremely short half-life makes research-market injection effects unpredictable
·No long-term human safety data
·Research-chemical supply — purity, sterility and identity unverified

Contraindications

·Active cancer or history of cancer (pro-angiogenic signaling)
·Low blood pressure or use of blood-pressure–lowering medications
·Pregnancy or breastfeeding
·Proliferative diabetic retinopathy or other abnormal blood-vessel growth disorders
·Under 18 years of age
·Bleeding disorders or anticoagulant therapy without physician guidance (injection-site haematoma)
·Active skin infection, cellulitis, or lipohypertrophy at intended injection sites
·Inability to maintain sterile technique or safe sharps disposal
·Not FDA-approved for human therapeutic use — no verified purity, sterility, or potency standards
·Immunocompromised or transplant patients (unverified sterility and immunogenicity risk)
·Concurrent participation in drug-tested sport (WADA prohibited or non-cleared substance)
·Known hypersensitivity or prior reaction to this compound or any excipient/diluent
·Pregnancy, attempting conception, or breastfeeding unless prescribed and monitored by a physician
·Children and adolescents with open growth plates (unless under specialist endocrine care)
·Active or recently treated malignancy without oncology clearance
·Use without a confirmed diagnosis, baseline labs, and licensed clinical supervision

Regulatory

Not FDA-approved for any use. Investigational research compound; sold as a research chemical. Not listed by name on the WADA prohibited list, but may fall under its general non-approved substances clause.

Veterinary Use (Pets)

No established veterinary protocol for Apelin-13. Consult a licensed veterinarian before considering off-label use in any species.

Full veterinary reference →

Functional Groups

Longevity Mitochondrial Bodybuilding & Performance Recovery

Cited Works

Tap any study to open the published work.