Melanin-Concentrating Hormone
Also known as: MCH, MCH-1, pro-MCH
Cyclic neuropeptide; hypothalamic orexigenic peptide
What it is
Researchers studying appetite regulation, obesity, and sleep are most interested in melanin-concentrating hormone (MCH). It is a brain neuropeptide produced in the hypothalamus that promotes eating and fat storage. Scientists are investigating whether blocking its receptor could offer a new way to treat obesity and related metabolic conditions.
The scientific side
melanin-concentrating hormone (MCH) is a 19-amino acid cyclic neuropeptide produced by neurons concentrated in the lateral hypothalamic area and zona incerta of the mammalian brain. It acts by binding to two class A G protein-coupled receptors: MCHR1, which couples predominantly to inhibitory Gi/o proteins, and MCHR2, which couples to Gq/11. Cryo-electron microscopy structures at 3.01 and 2.40 angstrom resolution reveal that MCH adopts a cysteine-mediated hairpin loop configuration when bound to both receptors, with a central arginine from the peptide's LGRVY core motif penetrating deeply into the transmembrane pocket to trigger receptor activation. MCHR1 activation in the nucleus accumbens shell reduces phosphorylation of GluR1 at serine 845 through Gi/o signaling, decreasing surface expression of AMPA receptors and suppressing medium spiny neuron firing, a mechanism that increases food intake by disinhibiting feeding circuits. MCH promotes feeding through the lateral septum as well: bilateral lateral septum infusion of MCH elicited a rapid and long-lasting increase in consumption of both standard chow and high-sugar diets in male and female mice, an effect blocked by co-administration of the MCHR1 antagonist TC-MCH 7c. Prostaglandin E2 (PGE2), a hypothalamic inflammatory mediator, can depolarize MCH neurons via EP2 receptor-mediated inhibition of the electrogenic Na+/K+-ATPase, linking chronic high-fat diet-driven hypothalamic inflammation to increased MCH neuron activity and subsequent diet-induced obesity; genetic deletion of EP2 receptors on MCH neurons was protective against obesity and liver steatosis. Beyond energy balance, MCH signaling influences non-REM sleep, anxiety-like behavior, locomotor activity, and reward processing. A meta-analysis of MCH-signaling-deficient mice confirmed that deletion of MCH or MCHR1 suppressed body weight, fat mass, and plasma leptin while increasing wakefulness and locomotor activity. Acute MCH administration increases food intake; chronic overexpression or intracerebroventricular infusion in rodents causes weight gain predominantly as increased fat mass. Conversely, mice lacking MCH, MCH-containing neurons, or MCHR1 are resistant to diet-induced obesity. MCH neurons also store and release the peptide via secretogranin-dependent granule mechanisms.
Class: Cyclic neuropeptide; hypothalamic orexigenic peptide
Administration & storage
- Administration
- Intracerebroventricular (ICV) infusion — rodent and ovine research models onlyBilateral intra-nucleus accumbens microinjection — rodent models onlyBilateral lateral septum infusion — rodent models onlyIntrathecal administration — referenced in one bariatric surgery study (PMID: 34155969)Intraperitoneal injection of MCH antagonist — used in mouse obesity models (PMID: 34155969)
- Storage
- No human-use storage data exist in the reviewed abstracts. Neuropeptides of this class are generally stored lyophilized at -20 degrees Celsius; however, this is not stated for MCH specifically in the reviewed abstracts.
Legal & regulatory status
No approved drug product containing MCH itself exists for human use. Several small-molecule MCHR1 antagonists (e.g., AZD1979) reached early clinical testing in obesity but none has received FDA approval; these compounds…
MCH is not listed on the current WADA Prohibited List. No prohibition is documented in the abstracts reviewed.
No approved therapeutic product containing MCH or an MCHR1 antagonist has been authorized in Canada. The evidence base is preclinical and early-phase clinical only.
What it's studied for
- Obesity and body weight regulation Preclinical (rodent and non-human primate); early clinical (Phase I/II, no approved agent)
- Hedonic and reward-driven feeding behavior Preclinical (rodent)
- Sleep and wakefulness modulation Preclinical (rodent); early observational (human biomarker study)
- Metabolic syndrome and insulin resistance Preclinical (rodent and canine)
- Anxiety and stress-related behavior Preclinical (rodent)
- Neuroendocrine appetite-circuit interactions (circadian, developmental, and inflammatory contexts) Preclinical (rodent and non-human primate)
- Bariatric surgery and weight-loss mechanism research Preclinical (mouse); translational
Safety signals
- Promotion of diet-induced obesity and hepatic steatosis via MCH neuron overactivation
- Increased anxiety-like behavior (anxiogenesis) with MCH signaling in novel environments
- Disrupted MCHR1 signaling in early-onset obesity — loss of responsiveness to endogenous MCH
- Increased plasma corticosterone and HPA axis activation in MCH-signaling-deficient states
- MCHR1 antagonists well-tolerated but without demonstrated long-term clinical efficacy
- Increased insulin resistance linked to MCHR1 activity
- Elevated cardiovascular parameters (heart rate, mean arterial pressure) with MCH signaling deficiency
All studies (8)
Frequently asked
Does MCH cause weight gain or weight loss?
MCH itself is an appetite-promoting peptide: it increases food intake and, when chronically elevated or overexpressed in animal models, causes weight gain primarily through increased fat mass. Drugs that block the MCH receptor (MCHR1 antagonists) have shown weight-loss effects in preclinical studies. Five MCHR1 antagonist compounds have been tested in early human trials; they were reported as well-tolerated but none has been approved or shown long-term efficacy in people.
Is MCH available as a supplement or injectable for weight loss?
No. MCH is not approved as a drug or available as a legal therapeutic product for weight management in any jurisdiction based on the published literature reviewed. All administration of MCH or its receptor antagonists has been conducted in controlled laboratory animal settings using central nervous system injection methods not applicable to human self-use.
How does MCH relate to sleep?
Preclinical research in rodents shows that MCH signaling promotes non-REM sleep. When MCH or its receptor is genetically deleted in mice, animals have enhanced wakefulness and reduced non-REM sleep. A clinical study (NCT07392840) is exploring whether MCH levels in cerebrospinal fluid and blood predict postoperative cognitive dysfunction in elderly patients with pre-existing sleep disorders, but results are not yet available.
What is MCHR1 and why are drug companies interested in blocking it?
MCHR1 is the primary receptor through which MCH increases appetite and promotes fat storage. In animal models, mice lacking MCHR1 are leaner and resistant to diet-induced obesity. Small-molecule antagonists that block MCHR1 consistently reduce food intake and body weight in rodents. This made MCHR1 an attractive drug target for obesity; however, the compounds tested in humans have not yet produced sufficient efficacy to reach approval.
Does MCH affect mood or anxiety?
Preclinical studies show that MCH neurons influence anxiety-related behaviors. Deletion of MCH signaling in mice produces a complex pattern — mildly reduced anxiety on some behavioral tests but increased anxiety on others. MCH infused into the lateral septum promoted feeding in familiar home environments but not in novel anxiogenic settings, suggesting the system interacts with emotional context. Human data on MCH and anxiety are not yet available in the published literature.