Glycerin is Safe, Effective in Psoriasis Model

Psoriasis patients have reported that glycerin, an inexpensive, harmless, and slightly sweet liquid at the top of the ingredient list of many skin lotions, is effective in fighting their psoriasis, and scientists now have objective evidence to prove it. support their reports.

They found that, whether applied topically or ingested in drinking water, glycerin or glycerol, helps calm the scaly, red, raised, and itchy patches in their model of psoriasis, Dr Wendy Bollag, cellular physiologist and skin researcher at the Medical College of Georgia. and Charlie Norwood VA Medical Center and colleagues report in the International Journal of Molecular Sciences.

Studies also provide more evidence of the different ways that glycerin enables healthy maturation of skin cells through four stages that result in a smooth, protective skin layer. Psoriasis is an immune-mediated problem that typically appears in young adults in which skin cells multiply rapidly, building up into inflamed plaques.

“We now have experimental data to show what these psoriasis patients are reporting,” says Bollag, who nearly 20 years ago first reported in The Journal of Investigative Dermatology that glycerin, a natural alcohol and water attractor known to improve the appearance of the skin, has also helped it function better and safely by helping skin cells to mature properly.

Bollag’s first report led to many anecdotal reports from individuals and their reports ultimately led to the new published study.

Topically, glycerin is known to have a soothing and emollient effect. But another key part of its magic, which Dr. Bollag helped delineate, is its conversion to lipid, or fat, phosphatidylglycerol, which ultimately regulates the function of keratinocytes, our main type of skin cell, and suppresses inflammation. skin.

Glycerin enters the skin through pathways like aquaporin-3, a channel expressed in skin cells, and scientists at MCG have shown that once inside, Aquaporin 3 carries glycerin into the skin. phospholipase-D-2, an enzyme that converts fat in the outer cell membrane. into cellular signals, ultimately converting glycerin to phosphatidylglycerol.

In 2018, Bollag and his team reported that topical application of phosphatidylglycerol reduced inflammation and characteristic raised skin plaques in a mouse model of psoriasis. This time, they decided to examine the impact of its widely available precursor, glycerin.

For the new studies, they used imiquimod, which is known to produce psoriasis-like plaques on humans, using it for problems such as genital warts and certain skin cancers, to produce an animal model. . The mice either drank the natural sweet alcohol or the scientists applied it topically. Either way, glycerin helped reduce the development of characteristic skin lesions, scientists report, a finding that helps point out that glycerin works in several ways to improve skin condition.

Externally, glycerin showed its action as an emollient because even in mice lacking phospholipase-D-2, it was beneficial. Additionally, it appears to compete topically with hydrogen peroxide for space inside the aquaporin 3 channel. Hydrogen peroxide is commonly known as a mild antiseptic, but we also produce it and at low levels, it is a cell signaling molecule. But at high levels, hydrogen peroxide produces destructive oxidative stress, which can actually cause psoriasis.

Scientists found that topical glycerin reduced the levels of hydrogen peroxide entering skin cells. When they added glycerin and hydrogen peroxide at the same time directly to skin cells, they found that glycerin protected against the oxidative stress of hydrogen peroxide.

“Glycerol essentially outshines hydrogen peroxide by getting into it and preventing it from entering and increasing oxidative stress,” Bollag said. Oil and water don’t mix, so another way that glycerin can be helpful is by supporting the skin’s major role as a barrier to water permeability so that, in the extreme, when we are sitting in a tub, the bath water does not pass through our skin so we explode like a balloon, she says.

On the other hand, when glycerin was ingested by mice lacking in phospholipase-D-2, which converts fats or lipids in a cell’s membrane into signals, it just didn’t work. says Bollag, who confirmed their earlier findings that internally anyway, glycerin combines with the enzyme to produce the signal essential for skin cell maturation.

Some of their other more recent work goes into great detail about how phosphatidylglycerol decreases inflammation.

Bollag would like the next steps to include clinical trials with dermatologists and patients as well, and work to find a formulation researcher who can do what she thinks is the optimal combination: glycerin and phosphatidylglycerol in the same topical cream. .

The addition of phosphatidylglycerol itself, rather than just the glycerin that makes it, is essentially a safeguard because there is some evidence that in psoriasis, the essential conversion of glycerin to phosphatidylglycerol is not optimal. Bollag’s lab and others have shown reduced levels of Aquaporin 3 in psoriasis, which likely means less phosphatidylglycerol.

Going quickly to clinical trials should be relatively easy because, as with glycerin, there is already experience with the use of phosphatidylglycerol in humans. For example, it’s a component of some high-end cosmetics, Bollag says.

She suspects that this type of two-shot combination might help ward off the early signs of psoriasis and, with more advanced disease, use existing psoriasis treatments to control skin condition, then start applying glycerin. to help keep it that way.

Bollag and his colleagues reported in 2018 in the Journal of Investigative Dermatology that in a mouse model of psoriasis, phosphtidylglycerol reduced the inflammation and raised skin lesions characteristic of psoriasis.

Although its exact cause is unclear, psoriasis is an immune-mediated disease and patients experience higher levels of inflammation, as well as too many skin cells produced and then maturing abnormally. The increased inflammation also puts them at increased risk for problems such as heart disease.

Biologics used to treat psoriasis work in different ways to stem this overactive immune response, but in addition to their high cost, they can expose the patient to problems such as serious infections and cancer. The only side effect she has seen in about 20 years of working with glycerin and the clinical and cosmetic use already available is that it can leave the skin feeling slightly sticky.

Our bodies can make glycerol from the carbohydrates, proteins and fats that we eat or already have in our body.