Arbutin is a compound of hydroquinone and D-glucose, and it has been over 30 years since there have been serious studies on the skin lightening action of this substance. In the meantime, there have been debates and validation studies about the mechanism of action of this substance as well as its skin lightening efficacy and safety. Several analogs or derivatives of arbutin have been developed and studied for their melanin synthesis inhibitory action. Formulations have been developed to improve the stability, transdermal delivery, and release of arbutin, and device usage to promote skin absorption has been developed. Substances that inhibit melanin synthesis synergistically with arbutin have been explored. The skin lightening efficacy of arbutin alone or in combination with other active ingredients has been clinically evaluated. Combined therapy with arbutin and laser could give enhanced depigmenting efficacy. The use of arbutin causes dermatitis rarely, and caution is recommended for the use of arbutin-containing products, especially from the viewpoint that hydroquinone may be generated during product use. Studies on the antioxidant properties of arbutin are emerging, and these antioxidant properties are proposed to contribute to the skin depigmenting action of arbutin. It is hoped that this review will help to understand the pros and cons of arbutin as a cosmetic ingredient, and will lead to future research directions for developing advanced skin lightening and protecting cosmetic products.

https://www.mdpi.com/2076-3921/10/7/1129/pdf

Arbutin as a Skin Depigmenting Agent with Antimelanogenic and Antioxidant Properties.

Vitamin B3 (nicotinic acid, niacin) deficiency causes the systemic disease pellagra, which leads to dermatitis, diarrhea, dementia, and possibly death depending on its severity and duration. Vitamin B3 is used in the synthesis of the NAD+ family of coenzymes, contributing to cellular energy metabolism and defense systems. Although nicotinamide (niacinamide) is primarily used as a nutritional supplement for vitamin B3, its pharmaceutical and cosmeceutical uses have been extensively explored. In this review, we discuss the biological activities and cosmeceutical properties of nicotinamide in consideration of its metabolic pathways. Supplementation of nicotinamide restores cellular NAD+ pool and mitochondrial energetics, attenuates oxidative stress and inflammatory response, enhances extracellular matrix and skin barrier, and inhibits the pigmentation process in the skin. Topical treatment of nicotinamide, alone or in combination with other active ingredients, reduces the progression of skin aging and hyperpigmentation in clinical trials. Topically applied nicotinamide is well tolerated by the skin. Currently, there is no convincing evidence that nicotinamide has specific molecular targets for controlling skin aging and pigmentation. This substance is presumed to contribute to maintaining skin homeostasis by regulating the redox status of cells along with various metabolites produced from it. Thus, it is suggested that nicotinamide will be useful as a cosmeceutical ingredient to attenuate skin aging and hyperpigmentation, especially in the elderly or patients with reduced NAD+ pool in the skin due to internal or external stressors.

Mechanistic Basis and Clinical Evidence for the Applications of Nicotinamide (Niacinamide) to Control Skin Aging and Pigmentation.

Herbal glycosides in healthcare

It is well-known that increased oxidative stress caused by ultraviolet B (UV-B) radiation induces melanogenesis and activates metalloproteinases (MMPs), which degrade collagen and elastin fibers, leading to decreased skin elasticity. Various antioxidant agents, such as vitamin C and niacinamide, have been evaluated for use as treatments for photoaging or skin pigmentation. In this study, we evaluated the ability of a topical liquid formula of polydeoxyribonucleotide (PDRN), vitamin C, and niacinamide (PVN) delivered via a microneedling therapy system (MTS) to attenuate photoaging and pigmentation by increasing nuclear factor erythroid 2-like 2 (NRF2)/heme oxygenase-1 (HO-1) and decreasing MMP expression in a UV-B-radiated animal model. The effects of the PVN were compared with those of individual PDRN and hydroquinone (HQ) compounds. The expression of NRF2/HO-1 significantly increased in response to HQ, PDRN, and PVN in UV-B-radiated animal skin. The activity of nicotinamide adenine dinucleotide phosphate hydrogen oxidase decreased in response to HQ, PDRN, and PVN, and the superoxide dismutase activity increased. The expression of tumor protein p53 and microphthalmia-associated transcription factor and tyrosinase activity decreased in response to HQ, PDRN, and PVN, and this decrease was accompanied by decreased melanin content in the skin. The expression of nuclear factor kappa-light-chain enhancer of activated B cells and MMP2/3/9 decreased in response to HQ, PDRN, and PVN in UV-B-radiated skin. However, the expression of collagen type I α1 chain and the amount of collagen fibers that were evaluated by Masson’s trichrome staining increased in response to HQ, PDRN, and PVN. The contents of elastin fibers, fibrillin 1/2 and fibulin 5 increased in response to HQ, PDRN, and PVN. In conclusion, PVN delivered via MTS led to decreased melanogenesis and destruction of collagen and elastin fibers by MMPs, and, thus, PVN decreased skin pigmentation and increased skin elasticity.

/pdf/a-mixture-of-topical-forms-of-polydeoxyribonucleotide-2gkzoej5.pdf

A Mixture of Topical Forms of Polydeoxyribonucleotide, Vitamin C, and Niacinamide Attenuated Skin Pigmentation and Increased Skin Elasticity by Modulating Nuclear Factor Erythroid 2-like 2

Melasma is a common disorder of hyperpigmentation that affects populations globally and can adversely affect quality of life. Topical therapies—including hydroquinone and nonhydroquinone‐containing formulations—play a central role in the management of melasma.

Melasma hyperpigmentation: An overview of current topical therapeutics

Hyperpigmentation is a common concern of patients in aesthetic practice. There are various treatment options, but topical depigmenting agents such as hydroquinone (HQ) are usually a first-line option. Given HQ's side effects and potential controversy over its long-term use from prior animal studies, there is a consumer demand for non-HQ topical formulations that provide similar efficacy, but with a reduced adverse reaction profile to HQ. There is increasing evidence to support the use of selective growth factors, tranexamic acid, niacinamide, arbutin, and Vitamin C in improving hyperpigmentation. This study sought to determine whether a non-HQ topical formulation, composed of the aforementioned ingredients, could provide similar or improved efficacy to topical HQ, but with a reduced adverse reaction profile. This single-center, prospective, randomized, controlled split face study investigated the safety and efficacy of a proprietary product SKNB19 compared with hydroquinone 4% (HQ4%) in treating hyperpigmentation. Eighteen adult subjects with facial pigmentation were randomly assigned to have one side of their face treated with SKNB19 twice a day (morning and night application) and the other treated with HQ4% applied nightly. Patients used a 5-point scale to self-assess their overall appearance, and a 4-point scale to assess redness, irritation, and tolerability to the skin-brightening creams. A Wilcoxon signed-rank test was used to test whether there was a statistical difference between the two treatments. Three-dimensional imaging was performed before treatment was administered and again 1 month following treatment initiation using a Canfield Vectra 3D imaging system. Five independent reviewers comprising two dermatologists, two facial plastic surgeons, and one oculoplastic surgeon graded and performed a qualitative comparative assessment of each side of the face using the before and after images. A Wilcoxon signed-rank test was used to test whether there was a statistical difference in overall appearance between SKNB19- and HQ4%-treated sides. SKNB19-treated hyperpigmentation had a statistically significant improvement in the overall appearance of hyperpigmentation and was shown to be 28.5% better than HQ4%-treated skin in the patient self-assessment and 27% better than HQ4%-treated skin in the independent reviewer assessment. On pair-wise comparison, the independent reviewer assessment also showed that 88.2% of the SKNB19-treated sides appeared equal or better than the HQ4%-treated sides. One patient dropped out of the study because of severe intolerance to HQ4%. No patients experienced intolerance to SKNB19, and all were able to continue its use without adverse effects. SKNB19-treated hyperpigmentation also had a statistically significant reduction in irritation when compared with HQ4%-treated hyperpigmentation. Patients reported a reduction in redness when using SKNB19 as opposed to HQ4%, but these figures did not reach statistical significance. This study supports that SKNB19, a recently developed non-HQ proprietary product, is safe and effective in improving hyperpigmentation. SKNB19 significantly improved the appearance of hyperpigmentation when compared with HQ4% in both patient self-assessment and independent reviewer assessment. SKNB19 exhibited a lower adverse reaction profile and was significantly better tolerated than HQ4%. SKNB19 should be considered as a safe and effective non-HQ alternative for the management of hyperpigmentation.

Evaluating the Safety and Efficacy of a Topical Formulation Containing Epidermal Growth Factor, Tranexamic Acid, Vitamin C, Arbutin, Niacinamide and Other Ingredients as Hydroquinone 4% Alternatives to Improve Hyperpigmentation: A Prospective, Randomized, Controlled Split Face Study

Nima L Shemirani

Papers

Evaluating the Safety and Efficacy of a Topical Formulation Containing Epidermal Growth Factor, Tranexamic Acid, Vitamin C, Arbutin, Niacinamide and Other Ingredients as Hydroquinone 4% Alternatives to Improve Hyperpigmentation: A Prospective, Randomized, Controlled Split Face Study