Melanotan 2

Potential Benefits of Melanotan 2

• Treats erectile dysfunction [1-9]
• Helps lose weight [10-17]
• Prevents cancer [18-19]
• Prevents heart disease [20-22]
• Promotes healthy brain [23-28]
• Treats inflammatory disorders [29-30]
• Improves blood sugar levels and treats symptoms of diabetes [31-33]
• Treats alcohol abuse disorder [34-37]

What is Melanotan 2?

Melanotan 2 or MT-2 is a synthetic analog of the peptide hormone α-melanocyte-stimulating hormone. It is used to induce erections in men with erectile dysfunction and increase sexual arousal in women.

How Melanotan 2 Works?

Melanotan 2 is similar to the melanocyte-stimulating hormone, a substance found in your body that is responsible for the production of skin-darkening pigments called melanin. It works by binding with melanocortin receptors. Melanotan 2 binds to MC-1R to stimulate the darkening of the skin and hair. It also stimulates penile erection by binding to MC-4R.

Chemical Structure of Melanotan 2

Research on Melanotan 2

Treats Erectile Dysfunction

Evidence suggests that MT-2 has beneficial effects on sexual function:

1. In men with psychogenic erectile dysfunction, MT-2 treatment successfully resulted in penile erections. [1]
2. In men with erectile dysfunction (ED), MT-2 treatment led to increased sexual desire and penile erection even without any sexual stimulation. [2-3]
3. In rats, MT-2 induced erections sufficient for sexual intercourse. [4]
4. In rabbits, intravenous injection of MT-2 resulted in increased pressure within the erectile tissue. [5]
5. In normal male volunteers, administration of MT-2 produced spontaneous, penile erections after 1-5 hours. [6]
6. A rat study showed that MT-2 was effective for skin tanning and could be used to prevent sunlight-induced skin cancers. [7]
7. In men with psychogenic erectile dysfunction, MT-2 was effective in inducing an erection. [8]
8. In male rats, MT-2 injection successfully induced penile erection. [9]

Helps Lose Weight

Studies also found that MT-2 has fat-burning effects that can be beneficial in overweight and obese individuals:

1. In obese rats, MT-2 treatment resulted in increased fat breakdown. [10]
2. In rats, peripheral MT-2 treatment led to weight loss. [11]
3. A study showed that MT-2 could safely reduce fat mass without inducing apoptosis (programmed cell death) in rats. [12]
4. A study showed that continued MT-2 application consistently induced weight and fat loss in rat subjects. [13]
5. In rats, MT-2 treatment effectively reduced body mass without long-term food restrictions. [14]
6. A rat study also found that MT-2 treatment decreased food intake and increased energy expenditure. [15]
7. A study suggested that MT-2 treatment could be effective in treating obesity by stimulating leptin and melanocortin pathways in the brain.[16-17]

Prevents Cancer

Studies show that MT-2 also exerts anti-cancer properties that can help protect against skin cancer:

1. A study suggested that MT-2 application could prevent sunlight-induced skin cancer. [18]
2. In healthy volunteers, it was found that MT-1 was safe and effective for skin tanning when combined with solar UV light, and has protective effects against sunlight-induced skin cancer. [19]

Prevents Heart Disease

MT-2 has also been shown to exert cardioprotective properties:

1. In mice, MT-2 treatment had therapeutic benefits in pre-established atherosclerosis (plaque formation within the heart arteries) by limiting inflammation and promoting vascular endothelial function. [20]
2. In patients with coronary heart disease, it was found that they have altered levels of MT-2 in the heart. [21]
3. In an animal model of myocardial ischemia (inadequate blood flow to the heart), MT-2 treatment improved heart function by reducing oxidative stress and programmed cell death. [22]

Promotes Healthy Brain

Evidence suggests that MT-2 is essential for optimal brain function:

1. In rats, it was shown that treatment with melanocortin receptor agonists like melanotan 2 could regulate the activity of central dopamine neurons in the brain. [23]
2. In a mouse model of stroke, MT-2 treatment improved working memory. [24]
3. In rats, it was found that MT-2 levels were impaired in the group with cognitive dysfunction. [25]
4. A study reported that MT-2 may potentially treat mental disorders such as depression and anxiety. [26]
5. In rats, MT-2 promoted nerve regeneration in the brain and protected against injury. [27]
6. In a maternal immune activation (MIA) mouse model of autism, MT-2 administration reversed the negative behaviors associated with autism spectrum disorder (ASD). [28]

Treats Inflammatory Disorders

A good deal of evidence supports the anti-inflammatory properties of MT-2:

1. In a mouse model of stroke, MT-2 treatment inhibited brain inflammation. [29]
2. In mice with plaque build-up within the heart, MT-2 inhibited plaque inflammation and promoted vascular endothelial function. [30]

Improves Blood Sugar Levels and Treats Symptoms of Diabetes

Studies suggest that MT-2 can help stabilize blood sugar levels and treat diabetic symptoms:

1. In rats, injection of MT-2 reduced food intake and body weight and improved insulin sensitivity. [31]
2. In rats fed with a high-fat diet, MT-2 reversed diabetes by suppressing the hypothalamic-pituitary-adrenal axis. [32]
3. In mice, MT-2 and leptin administration induced increased glucose uptake in skeletal muscles. [33]

Treats Alcohol Abuse Disorder

MT-2 has also been found to significantly reduce alcohol intake which makes it beneficial for those with alcohol abuse disorder:

1. In male rats who were subjected to long-term voluntary alcohol consumption, MT-2 reduced alcohol intake. [34]
2. In mice, MT-2 administration reduced binge-like ethanol drinking. [35]
3. In a mouse model of alcohol abuse disorder, low-dose MT-2 reduced binge-ethanol drinking. [36]
4. In rats, MT-2 administration through injections at the border of the central amygdala nucleus and the basolateral amygdala resulted in reduced alcohol intake while increasing their water intake. [37]

Associated Side Effects of Melanotan 2

Melanotan 2 side effects are very uncommon. There have been some side effects associated with the use of this drug wherein the patient had one of the issues listed below at some point while being on melanotan 2. However, these side effects weren’t confirmed to be associated with the treatment and could have been a coincidence and not related to the use of melanotan 2. Despite this, it was listed as a side effect associated with melanotan 2 even though these associated side effects are very uncommon.

Side effects associated with melanotan 2 may include the following:

• Agitation
• Darkening of the skin
• Facial flushing
• Fatigue
• Increased blood pressure
• Increased heart rate
• Increased moles and freckles
• Increased sweating
• Loss of appetite
• Nausea
• Spontaneous erections
• Vomiting

References

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2. Wessells H, Levine N, Hadley ME, Dorr R, Hruby V. Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II. Int J Impot Res. 2000 Oct;12 Suppl 4:S74-9. doi: 10.1038/sj.ijir.3900582. PMID: 11035391.
3. Wessells H, Gralnek D, Dorr R, Hruby VJ, Hadley ME, Levine N. Effect of an alpha-melanocyte stimulating hormone analog on penile erection and sexual desire in men with organic erectile dysfunction. Urology. 2000 Oct 1;56(4):641-6. doi: 10.1016/s0090-4295(00)00680-4. PMID: 11018622.
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