Inhibitors of melanocyte function

1、Endothelin antagonist

It is extracted from Chamomile, a European herb, and can fight endothelin and inhibit melanocyte production. The uneven distribution of endothelin in skin is the main factor leading the formation of pigmentation. Endothelin antagonists can inhibit the activation of tyrosinase by endothelin and promote the differentiation of melanocytes, which has the effect of high efficiency and uniform distribution of melanin.

Researchers study found that the extract from aquatic organisms endothelin antagonist small toxicity, inhibits the differentiation of endothelin of melanocyte and the activity of tyrosinase, is considered by ultraviolet (UV) radiation or other causes of skin pigment due to increased endothelin - l increase sexual disease may have application prospect.

2.Resveratrol and derivatives

Resveratrol is mainly found in grape, polygonum cuspidatum, veratrol and other plants. It can inhibit melanocyte function and tyrosinase activity in a concentration-dependent manner, thereby reducing melanin synthesis. Researcher Jeong found that it was also related to tyrosinase-related proteins [tyrosinase-related protein (TPR) -1, TPR] and microophthalmic associated transcription factor (MITF) in melanogenesis. Moreover, mRNA and protein expression of transcription factors were inhibited in a concentration dependent manner.

Researcher Jia Lili showed that the topical use of resveratrol can effectively improve skin color, has whitening effect, and no adverse reactions, good safety. Resveratrol has the disadvantages of instability and poor bioavailability. It has been found that its derivatives (pentacyl ether derivatives and tetraester derivatives) have high bioavailability and can better inhibit the synthesis of melanin, which has a broad application prospect in skin whitening cosmetics.

3、Saururus chinensis extract

Saururus chinensis is a plant belonging to the family Trichoderma. Researcher Liu Xiaoxin found that the extract of Saururus chinensis can inhibit the proliferation and tyrosinase activity of B16 melanoma cells, and reduce the content of intracellular melanin. Studies have found that skin care cream containing Sanbai grass extract is less irritating and stable to human skin, and its whitening effect is better than that containing arbutin. As a new type of plant source whitening agent, the extract of Saururus chinensis will have broad development and application prospects in the field of cosmetics.

4、Camellia extract

Camellia is a plant of the Camellia family. Researcher Nakamura found that camellia buds extract could inhibit melanogenesis and promote fibroblast differentiation. According to the study of Huang Xiaofeng, the extract of leaves and branches of Yunan Camellia has better effects on cell proliferation and inhibition of tyrosinase activity than arbutin, and the safety is better than arbutin. It is a new skin whitening agent with broad application prospects.

Inhibitors of melanin synthase

1、Arbutin

It is an important tyrosinase inhibitor, which can inhibit THE activity OF TYrosinASE, block the synthesis of DOPA and dopA quinone, so as to inhibit the generation of melanin. It can also significantly reduce the pigmentation caused by ultraviolet light, but it has poor stability and certain photosensitivity.

It was found that arbutin at a concentration of 3% is safe, less cytotoxic, less irritating and less allergic, and the upper limit of its concentration could not exceed 7%. High concentration of arbutin would make normal skin decolorized. Glucopyranoside, the natural active ingredient of glucopyranoside, has a stronger inhibitory effect on human tyrosinase than arbutin, which is replaced by arbutin because it is more effective and stable.

2、Licorice extract

The main active ingredients are licorice, islicorice and licorice flavone. By dispersing the accumulated melanin, glycyrrhizin can make the skin melanin evenly distributed and achieve whitening effect. The main effect of glycyrrhiza flavone is to inhibit the activities of tyrosinase, DHICA oxidase and dopA tautomase.

The study found that the skin care products containing licorice extract and papain are helpful for treat melasma and post-inflammatory pigmentation, with less adverse reactions and certain efficacy and safety. The concentration of Licorice in whitening products is 10% ~ 40%, but the content of active components in licorice is not high, and purification is difficult and expensive.

3、Rhodiola extract

Salidroside and flavonoids are the main active components. Salidroside can reduce the damage of lipid and cell membrane caused by ultraviolet light. This extract can inhibit melanin synthesis and tyrosinase activity, and is an effective skin whitening agent. It was found that 1% and 5% rhodiola extracts did not cause adverse reactions in human body, and they were safe active ingredients in cosmetics, which had a broader prospect in cosmetics application.

4、Aloin

It is a low molecular weight plant glycoprotein extracted from aloe vera, which can reduce the skin darkening caused by ultraviolet(UV) rays, and has a good repair effect on the skin after sun exposure. Aloin is hydrophilic and has no cytotoxicity. The combination of aloin and arbutin can improve the whitening effect.

5、Plant polyphenols

It mainly exists in the skin, roots, leaves and fruits of plants, and its whitening effect is mainly related to its absorption of ultraviolet light, antioxidant elimination of free radicals, inhibition of tyrosinase and peroxidase activities. Ellagic acid is a kind of natural polyphenol, extracted from pomegranate peel, bark and various fruits and vegetables, it can inhibit the proliferation of melanocytes, inhibit the activity of melanocyte tyrosinase, reduce the synthesis of melanin, has a strong absorption of ultraviolet rays, by absorbing ultraviolet rays to prevent the sun or remove free radicals. Plant polyphenols are safe and effective ingredients, which have broad prospects for the development and utilization of cosmetics.

Melanin reducing and decolorizing agent and antioxidant

1、Tea leaf extract

Theaflavin and EGCG are whitening active ingredients extracted from tea leaves. Studies have found that theaflavin and EGCG can inhibit the transfer of melanin particles to keratinocytes, inhibit cell proliferation, inhibit tyrosinase activity, reduce the synthesis of melanin, so as to play a whitening effect.

In addition, still can prevent ultraviolet ray, oxygen free radical and other exogenous factors to accelerate the formation of melanin process and enhance whitening effect. The results showed that tea polyphenols had no harmful effect on chromosome and germ cells of animal cells. The results of 30days feeding test showed that tea polyphenols had no obvious toxic effect on animals.

2、Nicotinamide

It is the bioactive form of nicotinic acid (vitamin B3), which is widely exist in many root vegetables. Nicotinamide can inhibit the transfer of melanin particles to keratinocytes and reduce pigmentation. Researcher Patamu Mohemaiti found that nicotinamide was involved in the transport process of melanin and could accelerate the movement rate of melanosomes in melanocytes. The mechanism may be that nicotinamide affected the transport of substances in melanocytes by regulating the calcium pump, the expression of cytodynein and the movement of melanosomes. Topical nicotinamide can reduce collagen oxidation products and improve skin barrier function. Study also found that applying 5% nicotinamide to the skin product reduces facial stains in women, and adding 2% nicotinamide to sunscreen prevents tanning.

Skin exfoliant

1、AHA

AHA is a - hydroxy acid, mainly through penetration to the skin cutin layer, weakened promote bonding force between the aging cuticle cells, accelerate cells metabolism, promote cell death falls off, remove facial fine lines and fade out skin pigment, also can fight against free radicals, promote the formation of collagen, make skin white, smooth and elastic.

The mechanism of AHA make skin change is use concentration higher than 20% AHA to weaken the connection of keratinocytes, make keratinocytes containing melanin fall off, promote the proliferation of collagen fibers and mucins in the dermis, reduce skin aging, so as to achieve the effect of whitening and refreshing the skin.AHA can remove spots in the superficial epidermis, but has no effect on spots in the deeper epidermis or dermis. High concentration of fruit acid products can cause skin redness, sensitivity and ulceration. China stipulates that the content of A-hydroxy acid in cosmetics should not exceed 6% and the pH value should not lower than 3.5.

Disclaimer: This article is from "Journal of Clinical Dermatology". If copyright issues are involved in the works, please contact us to deal with them in time to avoid unnecessary economic losses to both parties.