Prostaglandin D2 For Hair Growth | Study Results

In this article you’ll learn everything you need to know about the molecule named Prostaglandin D2 and how it relates to hair loss.

Read the entire article because at the end I’ll show you some practical ways to use this information to help regrow your own hair successfully.

A Malicious Molecule

Prostaglandin D2, otherwise known as PGD2, is an eicosanoid responsible for many ill effects on the body.

Synthesized in peripheral tissues as well as the central nervous system, PGD2 is proven to:

PGD2 can cause severe or even deadly reactions for a small percentage of our population; however, if you are a man, the bullet point that made your heart rate pick up the most was probably the last one.

As you are probably well aware, male pattern baldness affects approximately seventy percent of the male Caucasian population before they hit the age of seventy.

The loss of hair leads men to feel less confident about themselves and their bodies. To make matters worse, there are only a few medically approved treatments for the condition, and even those courses of action can be downright dangerous or unhelpful.

Thankfully, a recent scientific breakthrough was published concerning the effects of Prostaglandin D2 on hair follicles. This means that a more reliable cure for slowed hair growth could soon be on the way.

Of Mice and Men: Dermatological Studies Correlating AGA and PGD2

Prostaglandin D2 Inhibits Hair Growth in Mice with Human Hair Follicles

4 graphs showing the effect of prostaglandin d2 on mice

A 2012 study conducted primarily by Dr. Garza of Johns Hopkins University and Dr. Cotsarelis of the University of Pennsylvania revealed that the presence of PGD2 is indicative of androgenic alopecia (AGA), the scientific term for male pattern baldness.

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The correlation was first hinted at when scientists found that, just before a laboratory mouse naturally went through its period of hair regression, a rise in the levels of PGD2 occurred.

From this finding, Dr. Garza and Dr. Cotsarelis hypothesized that large quantities of PGD2 in the skin inhibited hair growth, likely through the Gpr44 receptor.

To test this hypothesis, laboratory mice were implanted with human hair follicles. Then, Prostaglandin D2 was applied topically to some of the mice while other mice had a control vehicle-treatment applied.

This led to the mice treated with PGD2 having less luscious and long hair than their control peers, as you can see in the charts to the right.

Levels of Prostaglandin D2 Synthase are Much Higher in Men with AGA

Prostagladin D2 levels in bald versus fully haired men

In the same scientific article, Dr. Garza and Dr. Cotsarelis mention another segment of this groundbreaking scientific inquiry in which a large, unbiased screening was conducted with the scalps of men with either hair or AGA related baldness.

In this genetic analysis, the scalps with male pattern baldness had levels of the molecule responsible for synthesizing PGD2 three times higher than those not suffering from androgenic alopecia.

These initial results were checked using mRNA, proteins, and mass spectrometry.

The graphic to the left illustrates the extent to which PGD2 is present in bald scalps as compared to haired scalps. 

PGD2 and Its Gpr44 Receptor Keep Mice from Regenerating Hair Follicles after a Wound

Regenerated hair follicles after wound

In a related study, Dr. Garza teamed up with another group of Johns Hopkins scientists to determine if Prostaglandin D2 had any effect on the regrowth of wounded follicles, particularly through the receptor Gpr44.

They first used mass spectrometry to measure the amount of prostaglandins in full-thickness wounds inflicted on the lab mice.

Then, they analyzed the prostaglandins present in the wound at regular intervals to determine the stages of the healing process at which each variety of prostaglandin was most prevalent.

Their results showed that PGE2 and PGF2a were predominant during the beginning of the wound healing process, when the bulk of the repair work was being done.

During later stages of the wound healing, PGD2 levels increased.

A secondary part of the experiment inflicted wounds on 3 species of lab mice and monitored the prostaglandin levels throughout the healing process.

When the wound fully closed, the scientists examined the scars on the mice and recorded the number of regrown hair follicles on each one.

The scientists found that the mice species with the most PGD2 present in the closed wound also had the lowest average number of regenerated hair follicles. Mice with higher levels of PGE2 and PGF2a had higher levels of follicle regeneration.

After that, a direct correlation between PGD2, Gpr44, and hair follicle regeneration was sought. First, the scientists topically applied PGD2 to the healing wounds of some Wild Type mice while treating others with a control vehicle. In the top chart of the graphic to the right, the results are obvious.

The mice treated whose wounds were treated with PGD2 has significantly fewer regenerated follicles than the control mice.

Still, the scientists desired more conclusive results pertaining to the inhibitive qualities PGD2 presents for hair follicle regeneration.

Thus, they obtained knockout mice, which were genetically modified to be missing either Ptgdr or Gpr44, the two receptors that mediate PGD2 activity.

The knockout (KO) mice were joined by mice heterozygous for the Gpr44 receptor as well as some C57Bl/6J control mice. Each variety was wounded and allowed to heal.

It turns out, as observed in the middle chart, the Ptgdr KO mice had about as many regenerated follicles as the control, but the Gpr44 KO mice had many more regenerated follicles than the control. This shows that the presence of Gpr44 inhibits follicle regeneration.

From Androgens to Androgenic Alopecia

Through large quantities of research such as the studies mentioned above, Dr. Garza and his team support the claim that Prostaglandin D2 is a major contributor to androgenic alopecia.

This leaves the question of how, exactly, PGD2 contributes to the decrease in hair growth attributed to male pattern baldness. There is an informative illustration provided to the right for you to follow along as I explain.

Hair growth mechanism

It all starts with androgens, hormones that develop and regulate the male reproductive system. These androgens, such as testosterone, fuel the production of lipocalin-type prostaglandin D synthase (L-PGDS) since PGD2 is vital in preparing male reproductive systems.

Though these hormones, particularly testosterone, are vital in shaping mere boys into vigorous men, they are also proven to cause AGA over the long term in men who are genetically predisposed to the condition.

Since women only produce about one twelfth of the androgen men create, this explains why women don’t ordinarily go bald while their husbands do.

PGD2 is created through a long and complicated process known as the arachidonic acid cascade, which is shown in the oval diagram within the illustration above.

Once a stimulus activates a cell’s phospholipid membrane, phospholipase releases arachidonic acid from the membrane.

The arachidonic acid is metabolized by the COX enzyme to become PGH2. Prostaglandin H2 is a sort of origin prostaglandin, as its molecular structure can be modified through various synthase reactions to become a prostaglandin such as PGE2, PGF2a, or PGD2.

If circumstances are right, the arachidonic acid cascade can create a high level of PGD2 while lowering the amount of PGE2 in the region. As you know from earlier, Prostaglandin D2 inevitably results in the slowing of hair growth.

However, it might come as a surprise that other forms of Prostaglandin such as PGE2 and PGF2a are actually linked to an increase in hair growth speed.

There is a sort of “Yin-Yang” balance when it comes to Prostaglandin: some forms are good for you, others not so much. Both PGE2 and PGD2 are located within compartments in the hair follicle, so they have direct impact on the development of the hair.

Female scalps seem to contain hair follicles that produce more prostaglandin than men, especially the good PGES and PGFS. This could be another reason why a majority of women don’t experience massive hair loss as they age.

The rise in PGD2 levels leads to the activation of Gpr44 protein, also known as the prostaglandin D2 receptor. Gpr44 has been shown to statistically be nominally significant in association to AGA.

When this protein is activated, it spurs the activation of effector proteins that in turn shrink hair follicles and create a physiological response: the slowing of hair growth.

How to Stop Prostaglandin D2 Before it Stops Your Hair

Pathways to a Cure

Hair growth phase is important to understand the reasons behind hair lossScientifically, a cure could in fact be very close. Since Prostaglandin D2 is a known cause of slowed hair growth, dermatologists are looking into ways to limit the production of this dangerous eicosanoid.

This could involve impeding a step in this prostaglandin’s pathway such as inhibiting the capability of Prostaglandin D Synthase to produce PGD2.

Another solution would be hindering the ability of PGD2 to attach to Gpr44 or CRTH2 receptors, therefore increasing the anagen, or growth, phase of hair.

Since Prostaglandin D2 plays such a large role in allergic reactions, inflammation, and asthma, many companies are doing research into halting its effects. Some of these drugs have made it quite a ways in the research pipeline, according to an interview with Dr. Garza.

Though these drugs would most likely take the form of tablets, they could easily be modified into topical applications, according to Dr. Cotsarelis.

Drugs containing a diverse range of CRTH2 antagonists and Gpr44 antagonists are going through clinical trials and some are already on the market. These PGD2 inhibitors include:

Sadly, if you are already completely bald, this cure will most likely come too late. According to Dr. Tobin, a professor at the University of Bradford in England, “It would be too much to turn the clock back and reverse very extensive hair loss.”

Dr. Cosarelis is more optimistic, saying that more research is needed to fully determine whether the effects of Prostoglandin D2 can be reversed.

Either way, I have gathered some information on topically applied therapies that can slow down further loss of hair until new PGD2 inhibiting drugs enter the dermatological market. The best part is that you can make them yourself at home for little to no cost.

Home Remedies for Slowing the Progress of Male Pattern Baldness

According to Dr. Ray Sahelian, aspirin and ibuprofen are mild prostaglandin inhibitors, as evidenced by their anti-inflammatory power. However, since prolonged use of this medication can have serious consequences, it is not recommended that you take large doses for an extended amount of time.

If you a persistent, another possible cure involves Quercetin, a natural inhibitor of PGD2. Since taking Quercetin tablets orally isn’t the most logical solution to curing a scalp disorder, a DIY topical application has been designed.

It is recommended to dissolve one tablet in one third cup filtered water, then add one third cup oil such as jojoba so that the concoction will be able to penetrate your scalp’s tough outer layer.

After that, add Lecithin or an alternate emulsifier and slowly mix everything. Once the mixture is homogenous, apply it thoroughly to your scalp and let it soak for at least half an hour.

Keep in mind that hair grows extremely slowly; it could take up to half a year to start seeing results.

A much simpler solution is to massage olive oil into your scalp for a few minutes at least once a day. My grandmother tried this approach after having brain surgery.

She kept with it and now her hair is fuller than it was before the operation. You could substitute olive oil for any number of things:

The largest requirement for all of these home remedies is, of course, consistency.


There is strong evidence that Prostaglandin D2 is at least partially responsible for male pattern baldness.

Now that you know how and why PGD2 effects your scalp, you will be better prepared to assess the breakthrough baldness treatments that are constantly emerging and determine which are most likely to yield positive results.

2 thoughts on “Prostaglandin D2 For Hair Growth | Study Results”

  1. I new that I may partially bald from a early age, I was always thing in the middle. At front my hair still grows a little but in the middle not as much or more smooth than the front.


    reynaldo serrant

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