Mucuna pruriens, a Possible Treatment for Depressive Disorders

The scientific paper Mucuna pruriens, a Possible Treatment for Depressive Disorders by Mata-Bermudez et al. explores the therapeutic potential of Mucuna pruriens—a legume rich in L-Dopa and other active compounds—as a natural alternative for treating depression. Given the limitations of conventional antidepressants, including side effects and lack of efficacy for many patients, the authors compiled preclinical evidence from various animal studies to examine how this plant may influence mood-regulating systems. The review highlights Mucuna pruriens’ ability to modulate key neurotransmitters like dopamine, serotonin, and norepinephrine, as well as its antioxidant, anti-inflammatory, and cortisol-lowering effects. The paper calls for further clinical research to evaluate its safety and effectiveness in human patients suffering from depressive disorders.

Depression is one of the most common mental health problems in the world. It can make people feel very sad, hopeless, tired, and uninterested in things they used to enjoy. The World Health Organization (WHO) says that depression affects around 280 million people globally, and it became even more common after the COVID-19 pandemic. The study notes that the pandemic “led to a 27.6% increase in global cases due to social isolation, reduced mobility, and heightened stress.” These changes especially affected women and young people.

While many people use antidepressants to feel better, not everyone benefits from them. Some people experience side effects like nausea, weight gain, or insomnia. Others find the medications too expensive or not effective enough. The study says, “around 20% of patients with depression do not respond to these treatments.” Because of these problems, many researchers and patients are interested in safer, more natural treatments.

One plant that scientists are now exploring is Mucuna pruriens, also called the velvet bean. It’s a climbing plant found in places like India and Africa and has been used in traditional medicine for hundreds of years. The plant contains several powerful natural chemicals, including L-Dopa, which is known to help with brain function. L-Dopa is also the main ingredient in some drugs for Parkinson’s disease.

This scientific paper reviews many studies that show how Mucuna pruriens might help treat depression. The plant seems to work by improving the balance of essential brain chemicals, reducing stress, and calming inflammation—all of which play prominent roles in depression.

The authors of this study didn’t do one experiment but instead looked at many other studies already done on Mucuna pruriens. Most of these involved animals, like rats and mice. Scientists used these animals to test signs of depression and see how the plant affected them. They used tools like:

• Forced Swim Test (FST): This test looks at how long an animal keeps trying to swim before giving up. Giving up early may show signs of hopelessness.
• Tail Suspension Test (TST): In this test, mice are suspended by their tails, and researchers observe how much they struggle. Less movement may suggest depression-like behavior.
• Sucrose Preference Test: Animals are given sweetened water. If they don’t show interest in it, that can be a sign of anhedonia, which means not enjoying things.

The researchers also looked at how the plant changes levels of brain chemicals like dopamine, serotonin, and norepinephrine. They examined its effects on cortisol (a stress hormone), inflammation, oxidative stress, and nitric oxide. The study also included some small human trials—mostly in people with Parkinson’s disease or infertility—to see how safe and helpful the plant is.

One of the biggest reasons Mucuna pruriens may help with depression is because it changes levels of important chemicals in the brain.

Dopamine (DA) is one of the main ones. It helps control mood, motivation, and pleasure. Mucuna pruriens has high levels of L-Dopa, which the body turns into dopamine. In one experiment with mice, scientists gave them 100–200 mg/kg of Mucuna pruriens for 7 days. This “significantly reduced the immobility time in the forced swim test and the tail suspension test.” That means the mice kept trying to move and didn’t give up as quickly—just like how antidepressants help people stay motivated.

Another study used haloperidol, a drug that blocks dopamine. When researchers gave haloperidol to mice after Mucuna pruriens, the antidepressant effects went away. This shows dopamine is vital for how the plant works. The paper says, “This action was inhibited by administering haloperidol… indicating dopamine’s role.”

Serotonin (5-HT) is also crucial for mood and sleep. When scientists gave mice Mucuna pruriens for 7 to 14 days, the animals acted less depressed. But when the scientists blocked serotonin with a drug called p-CPA, the plant stopped working. This means serotonin also plays a big part in how Mucuna pruriens helps. The study adds, “This effect was reversed by p-chlorophenylalanine… suggesting that the antidepressant action… is regulated by interaction with the serotonergic system.”

Norepinephrine (NE) helps with alertness and energy. When this chemical is low, people may feel tired or unmotivated. Mucuna pruriens has been shown to increase NE in both animal studies and human studies with infertile patients. One part of the study says, “It could increase noradrenaline concentrations in a rat model of Parkinson’s disease.”

Together, these brain chemicals play significant roles in depression, and Mucuna pruriens helps boost all three.

Stress is one of the biggest causes of depression. The hormone cortisol helps the body handle stress, but it can hurt the brain when it stays too high. In people with depression, cortisol is often out of balance. The study explains, “Almost 80% of patients diagnosed with major depressive disorder have impaired cortisol secretion.”

In animal studies, Mucuna pruriens helped bring cortisol levels back to normal. One study gave the plant to rats for 20 days and saw a “reduction in corticosterone concentrations.” In human studies, infertile men who took Mucuna pruriens also had lower cortisol levels.

The plant also helps reduce inflammation in the brain. Inflammation is when the body makes too many chemicals that can damage cells. These chemicals include IL-6, TNF-α, and IL-1β. In tests with brain cells, Mucuna pruriens lowered the levels of these harmful markers. One experiment found it “decreased release of inflammatory mediators such as IL-1β, IL-6, and TNF-α.” This is important because inflammation is now seen as a big cause of depression.

Oxidative stress happens when harmful molecules called free radicals build up in the body. They can damage cells, especially in the brain. This is also linked to depression. People with depression often have lower levels of antioxidant enzymes like SOD and CAT.

Mucuna pruriens has strong antioxidant power. It contains compounds like gallic acid, genistein, and flavonoids that help fight free radicals. In different animal models—like diabetes, brain injury, and Parkinson’s—Mucuna pruriens increased antioxidant activity and decreased damage. One study found it “increased the activity of antioxidant enzymes (SOD and CAT) in rats with liver damage.”

This shows the plant doesn’t just help the brain—it protects it too.

Nitric oxide (NO) is a gas that helps cells communicate, but too much of it can harm the brain and cause depression. Some studies show that people with depression have higher NO levels.

In the research, Mucuna pruriens lowered NO production in animals and lab-grown cells. It reduced the expression of iNOS, an enzyme that makes nitric oxide. The study says, “Extracts of Mucuna pruriens significantly inhibited NO production in BV2 microglial cells stimulated with lipopolysaccharide (LPS).”

Lower NO means less brain inflammation and better mood support.

This study shows that Mucuna pruriens may be a safe, affordable way to support mental health. It helps by balancing brain chemicals like dopamine, serotonin, and norepinephrine. It also lowers stress hormones like cortisol, fights inflammation, and protects brain cells from damage caused by oxidative stress and nitric oxide.

Some human studies have shown that plants help people with Parkinson’s disease and male infertility. These studies didn’t report major side effects. That gives hope that it could also be safe for people with depression.

The authors explain, "Mucuna pruriens represents a safe and affordable therapy." Still, they warn that more studies in humans are needed. The current research is intense in animals but limited in people. The study recommends "increasing the number and sample sizes of clinical studies… especially in treating depression."

The science behind Mucuna pruriens is exciting. This plant works in many ways that matter for mental health. It boosts feel-good brain chemicals, reduces stress hormones, lowers inflammation, and fights off damage to brain cells.

If future human studies confirm these effects, Mucuna pruriens could become a potent natural treatment for depression. It may offer hope to people who don’t get relief from regular antidepressants or want a more natural path to healing.

For now, the evidence suggests that Mucuna pruriens is not just a plant—it’s a potential game-changer in how we treat depression.