ascorbic-acid and azelaic-acid

Examine clinical trials performed for depigmenting agents in order to determine the most effective and well-tolerated depigmenting agent.. We searched clinical trials, published and unpublished, performed for hydroquinone, ascorbic acid, azelaic acid, retinol and niacinamide in the period 2009 till present. Studies were examined based on participant information, design, duration, intervention, outcome measurements and statistical significance.. Sixty-one studies were examined, 40 published and 21 unpublished. Design, outcome measures and intervention showed sources of bias were not avoided. Only 30% of published trials were double-blind, 27% used a placebo and 80% used subjective measurements for their results. Unpublished trials follow similar outcomes, however, did not provide any significant results.. Based on these results, we are unable to recommend a safer, more effective depigmenting agent. Lack of thorough trials limits us from accepting depigmenting agent full evaluation. To accept a depigmenting agent, its duration must test for long-term safety, clinical trial must be double-blind and comparative, use participants of the correct skin type and measure outcomes objectively. In addition, lack of results for parallel unpublished studies leaves room for discussion. Efforts toward creating more effective formulations are welcomed.

Topics: Ascorbic Acid; Clinical Trials as Topic; Dicarboxylic Acids; Double-Blind Method; Humans; Hydroquinones; Niacinamide; Patient Safety; Research Design; Skin Lightening Preparations; Skin Pigmentation; Vitamin A

So-called darkened age spots encompass distinct pathological processes. The efficacy of topical depigmenting agents is difficult to objectivate.. To assess the hypopigmenting effect of three cosmetic formulations using objective biometrological methods.. 50 women of South-East Asian ancestry were enrolled in this pilot study. They had solar lentigines according to dermoscopic criteria. The lesions were treated by topical hypopigmenting formulations. Products were applied twice daily for 2 or 3 months. Assessments at 1-month intervals were made using narrow-band reflectance spectrophotometry, image analysis of video-recorded ultraviolet light reflection and photodensitometry- and image-analysis-assisted corneomelametry.. A 20% azelaic acid formulation and another one containing 5% ascorbyl glucosamine, 1% kojic acid and alpha-hydroxyacid esters appeared inefficacious on solar lentigines. A stabilized soy extract showed a better although modest lightening effect when assessed by corneomelametry. The subclinical or faint mottled skin revealed by ultraviolet light examination better responded (p < 0.05) to treatments.. Focal epidermal hyperpigmentation is better controlled by topical whitening agents when the increase in melanin content reflects a modest functional hyperactivity of melanocytes.

Topics: Administration, Topical; Adult; Ascorbic Acid; Densitometry; Dermatologic Agents; Dicarboxylic Acids; Double Bind Interaction; Drug Combinations; Female; Forearm; Glucosamine; Glycine max; Hand; Humans; Image Processing, Computer-Assisted; Lentigo; Melanins; Melanocytes; Middle Aged; Pilot Projects; Plant Extracts; Pyrones; Sunlight

Vitamins C, E, and A and substances of plant origin, including azelaic acid and phytic acid are frequently used in cosmetic preparations to counteract oxidative stress and negative effects of free radicals. The aim of the study was to evaluate a novel combined therapy consisting of azelaic acid, ascorbic acid, and phytic acid applied layer on layer.. Twenty study participants received a series of eight treatments performed every 7 days. Twenty percent azelaic acid and then 30% phytic acid were applied to the entire face, while 40% l-ascorbic acid only on the left side. The preparations were applied layer by layer. Skin parameters were measured before the series of treatments (T0), after the series of eight treatments (T1-8 weeks), and 1 month after the end of the treatment (T2-12 weeks).. The application of two and three active compounds resulted in a significant improvement in erythema and hyperpigmentation both on the forehead and the cheeks, however, more pronounced effects were observed when all the three active compounds were used. Both applied types of treatment considerably increased skin moisture. All the participants (100%) were satisfied with the effects of the treatment. A majority of them reported an improvement in skin hydration, firmness, and elasticity, more uniform skin tone and a reduction of skin redness and wrinkles.. Topical application of these active compounds resulted in improvement of skin elasticity and flexibility, reduction of wrinkles, hyperpigmentation, erythema, and telangiectasia as well as amelioration of skin tone.

Topics: Aging; Ascorbic Acid; Female; Humans; Hyperpigmentation; Phytic Acid; Skin Aging; Vitamins

Excess fat intake induces hyperinsulinaemia, increases nutrient uptake and lipid accumulation, amplifies ROS generation, establishes oxidative stress and morphological changes leading to tissue injury in the liver, kidney and heart of high-fat diet (HFD)-fed mice. The effect of azelaic acid (AzA), a C9 α,ω-dicarboxylic acid, against HFD-induced oxidative stress was investigated by assaying the activities and levels of antioxidants and oxidative stress markers in the liver, kidney and heart of C57BL/6J mice. Mice were segregated into two groups, one fed standard diet (NC) and the other fed high-fat diet (HFD) for 15 weeks. HFD-fed mice were subjected to intragastric administration of AzA (80 mg/kg BW)/RSG (10 mg/kg BW) during 11-15 weeks. Glucose, insulin, triglycerides, hepatic and nephritic markers were analysed in the plasma and the activity of enzymatic, non-enzymatic antioxidants and lipid peroxidation markers were examined in the plasma/erythrocytes, liver, kidney and heart of normal and experimental mice. We inferred significant decrease in enzymatic and non-enzymatic antioxidants along with significant increase in glucose, insulin, hepatic and nephritic markers, triglycerides and lipid peroxidation markers in HFD-fed mice. Administration of AzA could positively restore the levels of plasma glucose, insulin, triglycerides, hepatic and nephritic markers to near normal. AzA increased the levels of enzymatic and nonenzymatic antioxidants with significant reduction in the levels of lipid peroxidation markers. Histopathological examination of liver, kidney and heart substantiated these results. Hence, we put forward that AzA could counteract the potential injurious effects of HFD-induced oxidative stress in C57BL/6J mice.

Topics: Animals; Antioxidants; Ascorbic Acid; Biomarkers; Blood Glucose; Body Weight; Dicarboxylic Acids; Diet, High-Fat; Eating; Erythrocytes; Glutathione; Glutathione Peroxidase; Glutathione Transferase; Heart; Hypoglycemic Agents; Insulin; Kidney; Liver; Male; Metabolic Syndrome; Mice; Mice, Inbred C57BL; Myocardium; Oxidative Stress; Rosiglitazone; Thiazolidinediones; Thiobarbituric Acid Reactive Substances; Triglycerides; Vitamin E