Covers compounds researched for their effects on insulin sensitivity, glycaemic control, mitochondrial metabolic function, and systemic metabolic health markers.
| Compound | Class | Primary Mechanism | Commonly Reported For | Link |
|---|---|---|---|---|
| Retatrutide | GLP-1/GIP/Glucagon triple agonist | Triple incretin receptor agonism; glucose-dependent insulin secretion; energy expenditure | Blood sugar regulation, metabolic improvement | View profile → |
| Tirzepatide | GLP-1/GIP dual agonist | Dual incretin agonism; superior insulin sensitisation vs GLP-1 alone | Type 2 diabetes research, insulin sensitivity | View profile → |
| Semaglutide | GLP-1 agonist | GLP-1 receptor agonism; slows gastric emptying; enhances glucose-dependent insulin release | Glycaemic control, cardiovascular metabolic risk | View profile → |
| MOTS-c | Mitochondria-derived peptide | AMPK activation; mimics exercise-induced metabolic adaptation; glucose uptake | Insulin resistance, metabolic aging | View profile → |
| NAD+ | Dinucleotide coenzyme | Sirtuin activation (SIRT1/SIRT3); mitochondrial bioenergetics; glucose metabolism | Metabolic decline, cellular energy, aging | View profile → |
The incretin system is the primary pharmacological target for the GLP-1 and dual/triple agonist compounds in this category. Incretins — principally GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide) — are gut-derived hormones released postprandially that amplify glucose-stimulated insulin secretion from pancreatic beta cells. Critically, this effect is glucose-dependent: incretin receptor agonists do not drive insulin release in the fasting state, which substantially reduces the risk of hypoglycaemia compared to insulin secretagogues that operate independently of glucose levels. Beyond insulin secretion, GLP-1 receptor agonism slows gastric emptying, reduces glucagon secretion from alpha cells, and acts centrally on hypothalamic satiety circuits. GIP co-agonism, as in tirzepatide, adds additional insulin sensitisation through adipose tissue pathways and may enhance energy expenditure independently of GLP-1 receptor action.
Comparative clinical data between tirzepatide and semaglutide has been generated through large randomised trials. The SURPASS programme established that tirzepatide produces greater HbA1c reductions and body weight loss at equivalent treatment durations compared to semaglutide, attributed to the additive or synergistic effect of GIP receptor co-agonism. Retatrutide — the triple agonist in this category — additionally targets the glucagon receptor, which increases energy expenditure and hepatic fat mobilisation beyond the incretin effect. Phase 2 data for retatrutide suggests metabolic outcomes exceeding those of dual agonists, though Phase 3 completion is required for full clinical characterisation. The progression from GLP-1 monotherapy to dual and triple agonism represents a systematic expansion of incretin-based metabolic targets.
Mitochondrial targets represent a mechanistically distinct approach to metabolic health. MOTS-c is a 16-amino acid peptide encoded within the mitochondrial 12S rRNA gene — an unusual genomic origin for a signalling peptide. Research has established that MOTS-c activates AMPK (AMP-activated protein kinase), a master energy sensor that responds to low ATP states by promoting glucose uptake, fatty acid oxidation, and mitochondrial biogenesis. This mechanism mimics aspects of exercise-induced metabolic adaptation, making MOTS-c a subject of interest in age-associated insulin resistance where mitochondrial function declines. NAD+ occupies a complementary position: as a cofactor for sirtuins (SIRT1, SIRT3) and PARP enzymes, it governs mitochondrial bioenergetics, DNA repair efficiency, and glucose-lipid metabolic flux. NAD+ levels decline with age, and research has investigated supplementation via precursors (NMN, NR) and direct IV administration for their potential role in reversing age-associated metabolic deterioration.
Retatrutide (LY3437943) is an investigational triple agonist developed by Eli Lilly, co-targeting GLP-1, GIP, and glucagon receptors in a single molecule. Phase 2 trial data published in 2023 demonstrated substantial body weight reductions and HbA1c improvements across doses, with metabolic outcomes exceeding published dual agonist benchmarks. The glucagon receptor component is theorised to drive increased energy expenditure and hepatic lipid mobilisation beyond incretin-only effects. Phase 3 trials are underway as of current literature. Reported side effects in research and anecdotal accounts include nausea, vomiting, and reduced appetite, consistent with GLP-1 class effects. It is not approved for any indication.
Tirzepatide is FDA-approved as Mounjaro for type 2 diabetes and as Zepbound for chronic weight management. It is a once-weekly subcutaneous injection combining GLP-1 and GIP receptor agonism in a single synthetic peptide. Clinical trials in the SURPASS programme demonstrated superior HbA1c reduction compared to semaglutide, insulin glargine, and dulaglutide. Its GIP component appears to enhance insulin sensitivity in adipose tissue and may reduce the gastrointestinal side effects associated with pure GLP-1 agonism. Commonly reported doses range from 2.5 mg to 15 mg once weekly, titrated over months. Its approved status provides a substantial safety and pharmacokinetic dataset for research reference.
Semaglutide is FDA-approved as Ozempic (diabetes) and Wegovy (weight management), with an oral formulation (Rybelsus) approved for type 2 diabetes. It is a GLP-1 receptor agonist with a fatty acid chain modification enabling once-weekly subcutaneous dosing through extended albumin binding. The SUSTAIN and SEMA programmes have generated robust cardiovascular outcome data: the SUSTAIN-6 trial demonstrated a significant reduction in major adverse cardiovascular events (MACE) in high-risk type 2 diabetes patients — positioning semaglutide as relevant to cardiovascular-metabolic risk research beyond glycaemic control alone. It remains the most extensively studied compound in this goal category with the largest published human dataset.
MOTS-c is a mitochondria-derived peptide encoded by the mitochondrial genome — a discovery that expanded understanding of mitochondrial signalling beyond energy production. Research has identified MOTS-c as an exercise-inducible peptide: plasma levels rise following physical activity, and its administration in rodent models mimics aspects of exercise-induced metabolic benefit including improved insulin sensitivity, increased glucose uptake, and resistance to diet-induced obesity. AMPK activation is the central mechanism, with downstream effects on GLUT4 translocation and fatty acid oxidation. Human research is at an early stage; the majority of published data comes from cell culture and rodent models. Commonly reported doses in research range from 5 mg to 10 mg subcutaneously.
NAD+ (nicotinamide adenine dinucleotide) is technically a dinucleotide coenzyme rather than a peptide, and its inclusion in this category reflects its central role in mitochondrial metabolic research. NAD+ serves as an electron carrier in oxidative phosphorylation and as a substrate for sirtuins (SIRT1, SIRT3) — NAD+-dependent deacetylases that regulate metabolic gene expression, mitochondrial biogenesis, and insulin signalling. Declining NAD+ with age is associated with impaired mitochondrial function, increased fat accumulation, and worsening insulin sensitivity in preclinical models. Research has investigated intravenous NAD+ infusion, oral NMN (nicotinamide mononucleotide), and NR (nicotinamide riboside) as strategies for restoring cellular NAD+ pools. Human trials are ongoing across several institutions.
No well-documented combination protocols have been identified for the metabolic health goal area. Incretin-class compounds (semaglutide, tirzepatide, retatrutide) are typically studied as monotherapies or against each other as comparators in clinical trials rather than in stacked configurations. MOTS-c and NAD+ operate via mitochondrial pathways distinct from incretin signalling, and combination data with GLP-1 class compounds has not been established in published research. Compounds in this category are generally investigated independently across their respective research programmes.
GLP-1 agonists stimulate insulin secretion in a glucose-dependent manner — meaning they amplify insulin release only when blood glucose is elevated. When glucose levels fall to the normal range or below, the incretin effect diminishes and insulin stimulation ceases. This contrasts with sulfonylureas and exogenous insulin, which can drive insulin secretion or action independently of glucose levels, creating genuine hypoglycaemia risk. Additionally, GLP-1 agonists suppress glucagon secretion from pancreatic alpha cells only in the presence of elevated glucose, preserving the counterregulatory glucagon response to actual hypoglycaemia. These glucose-gated mechanisms account for the favourable hypoglycaemia profile observed across GLP-1 class clinical trials.
Tirzepatide's dual GLP-1/GIP agonism already improves on GLP-1 monotherapy by adding GIP receptor-mediated insulin sensitisation and potentially reducing GI side effects through GIP's counterbalancing effect on GLP-1-induced nausea pathways. Retatrutide adds glucagon receptor agonism as a third axis. Glucagon receptor activation increases hepatic glucose output and energy expenditure — effects that seem counterintuitive in a diabetes context but are beneficial when balanced against incretin-driven insulin secretion. The net effect in Phase 2 trials was increased resting energy expenditure and greater fat mass loss, suggesting the glucagon component drives a thermogenic contribution that amplifies the incretin metabolic effect. The clinical significance relative to dual agonism in long-term outcomes awaits Phase 3 completion.
GLP-1 agonists act on gut-pancreatic-brain signalling circuits — they engage G-protein coupled receptors on pancreatic beta cells, hypothalamic neurons, and vagal afferents to modulate insulin secretion, satiety, and gastric motility. MOTS-c operates at the intracellular metabolic level via AMPK activation, an energy sensor that detects falling ATP-to-AMP ratios and responds by promoting substrate uptake and mitochondrial efficiency. MOTS-c's effect is not mediated through incretin signalling and does not directly modulate insulin secretion. Instead, it improves the peripheral response to insulin by increasing glucose uptake in skeletal muscle and improving mitochondrial function. The two mechanisms are therefore complementary in principle, addressing different nodes of the glucose-insulin system.
Head-to-head data has been generated through the SURPASS-SEMA trial and related analyses. Tirzepatide at its highest dose (15 mg weekly) produced greater mean HbA1c reductions than semaglutide 1 mg weekly — with approximately 2.0–2.3% HbA1c reductions for tirzepatide versus 1.5–1.9% for semaglutide in comparable populations. Body weight reductions also favoured tirzepatide. However, semaglutide has a more extensive published cardiovascular outcome dataset: the SUSTAIN-6 and SELECT trials demonstrated significant MACE reductions in high cardiovascular risk populations — data that does not yet exist for tirzepatide at equivalent follow-up durations. For pure glycaemic control, tirzepatide shows superior efficacy; for evidence of cardiovascular benefit, semaglutide currently has the stronger published record.