Patients with psoriasis have often reported that glycerine, common in many skin lotions, is effective at combatting their psoriasis and there is now objective evidence to support their reports.
Researchers found that whether applied topically or ingested in drinking water, glycerine, or glycerol, helps calm the classic scaly, red, raised and itchy patches in their psoriasis model, Dr. Wendy Bollag, cell physiologist and skin researcher at the Medical College of Georgia and Charlie Norwood VA Medical Center and her colleagues report in the International Journal of Molecular Sciences.
The studies also provide more evidence of the different ways glycerine enables the healthy maturation of skin cells through four stages that result in a smooth, protective skin layer. Psoriasis is an immune-mediated problem that typically surfaces in young adults in which skin cells instead multiply rapidly, piling up into inflamed patches.
“We have experimental data now to show what these patients with psoriasis are reporting,” said Dr Bollag, who nearly 20 years ago first reported that glycerine, a natural alcohol and water attractor known to help the skin look better, also safely helped it function better by helping skin cells mature properly.
Dr Bollag’s early report led to many anecdotal reports from individuals and their reports ultimately led to the newly published study.
Topically, glycerine is known to have a soothing, emollient effect. But once glycerine enters skin cells through the aquaporin 3 channel, the enzyme phospholipase-D-2 converts it to the lipid phosphatidylglycerol. Phosphatidylglycerol ultimately regulates the function of keratinocytes and suppresses inflammation in the skin. Dr Bollag and team previously reported that topical application of phosphatidylglycerol reduced inflammation and raised skin patches in a mouse model of psoriasis.
For this study, they focused on its glycerin precursor, which was either applied topically or fed to mice with induced psoriasis. Either way, glycerine helped reduce development of the characteristic skin lesions, showing that glycerin works in more than one way to improve the skin condition.
Glycerine worked as an emollient even in mice lacking phospholipase-D-2. It also seems to block hydrogen peroxide in the aquaporin 3 channel. At low levels, hydrogen peroxide is a cell signaling molecule, but at high levels results in destructive oxidative stress, possibly leading to psoriasis.
Topical glycerine 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 from hydrogen peroxide.
“Glycerol is basically outcompeting the hydrogen peroxide in getting in there and preventing it from being able to enter and increase oxidative stress,” Dr Bollag said. Glycerine could also help by maintaining the skin’s water permeability barrier.
On the other hand, when glycerin was ingested by the mice missing the phospholipase- D-2, it simply did not work, Dr Bollag said, which confirmed their earlier findings that internally anyway, glycerine pairs with the enzyme to produce the signal essential to skin cell maturation.
Some of their other most recent work is detailing more about how phosphatidylglycerol decreases inflammation.
Dr Bollag would like next steps to also include clinical trials with dermatologists and patients and is working to find a formulation scientist who can make what she thinks will be the optimal combination: glycerin and phosphatidylglycerol in the same topical cream.
The addition of phosphatidylglyerol itself, rather than just the glycerine that makes it, is essentially a backup since there is some evidence that in psoriasis the essential conversion of glycerin to phosphatidylglycerol is not optimal. Dr Bollag’s lab and others have shown reduced levels of aquaporin 3 in psoriasis, which likely means less phosphatidylgycerol, so making more glycerine available could somewhat help raise the availability of this key lipid.
She suspects that this sort of two-punch combination, could help keep early signs of psoriasis at bay and, with more advanced disease, use existing psoriasis treatments to get the skin condition under control then start applying glycerin to help keep it that way.
While its exact cause is unclear, psoriasis is an immune-mediated condition and patients have higher levels of inflammation, as well as too many skin cells being produced then maturing abnormally. The heightened inflammation also puts them at increased risk for problems like heart disease.
Biologics used to treat psoriasis work different ways to stem this overactive immune response but in addition to their high cost, can put the patient at risk for problems like serious infections and cancer. The only side effect she has seen in about 20 years of working with glycerine and the clinical and cosmetic use already out there, is sticky-feeling skin.
Source: MedicalXpress
