Primary Irritation Research Articles

Safety assessment of female sexual hygiene product containing cannabidiol in new zealand white rabbit and clinical trial

Cannabis is an herb known for its significant pharmacological effects. This study evaluated the safety of a female sexual hygiene product containing cannabidiol on the skin of experimental animals and humans. Irritation symptoms were tested using three female New Zealand white rabbits. In human trials, irritation and sensitivity symptoms were assessed in 30 healthy female volunteers. The results from the animal study indicated that body weight and clinical symptoms remained normal, with only slight irritation noted in the primary irritation index of the skin (PII = 0.6). In human trials, transepidermal water loss was observed during the induction phase but decreased over time. No abnormalities were found during the induction phase; however, irritation occurred during the challenge phase, which resolved after 8 h. It was concluded that the rinse-off product caused slight irritation when applied for more than 4 h in animals and 24 h in humans, which differs from its intended use of immediate rinse-off, where no irritation was observed.

Revisions to Limits for Toluene in Spacecraft Air.

INTRODUCTION: The original Spacecraft Maximal Allowable Concentrations (SMACs) for toluene (set for 1 h, 24 h, 7 d, 30 d, and 180 d) were first established by NASA in 1996 based on a human study in which no irritation or neurotoxicity was reported following 6-h exposure to 40 ppm toluene vapors. While the toluene SMACs were updated in 2008 to account for auditory, visual, and hormonal effects (for 7 d, 30 d, and 180 d) and to include a long-term SMAC (1000 d) in anticipation of longer spaceflight exploration missions, the short-term SMAC limits (1 h and 24 h) remained unchanged. Acute toluene exposure is reported to result in ocular and nasal irritation, although it is not a primary irritant, as well as central nervous system effects including headaches and dizziness. Long-term exposure to toluene can elicit hepatotoxicity, nephrotoxicity, neurotoxicity, and endocrine toxicity.RESULTS AND DISCUSSION: Since publication of the original and revised toluene SMACs, the National Academy of Sciences developed interim Acute Exposure Guideline Limits reviewed by the National Research Council Committee. Based on these data, we have increased the limits for toluene in crewed spacecraft to 40 ppm for 1 h, 24 h, 7 d, and 30 d. SMACs for durations of 180 and 1000 d will remain unchanged.changed.Tapia CM, Langford SD, Ryder VE. Revisions to limits for toluene in spacecraft air. Aerosp Med Hum Perform. 2024; 95(7):399-402.

Microbial Consortium of Jeju Traditional Fermented Foods and Their Cosmetic Ingredient Potential

In this study, we analyzed the microbial community of traditional fermented foods of Jeju Island to identify the distribution of useful microorganisms and confirm their anti-inflammatory and anti-melanogenic effects to determine their potential use as cosmetic ingredients. Firstly, we examined the microbial communities of Omphalius rusticus Jeotgal (OR), Spratelloides gracilis Jeotgal (SG), Chromis notata Jeotgal (CN), Turbo cornutus Jeotgal (TC), Trichiurus lepturus intestine Jeotgal (TL), Branchiostegus japonicus Sweet Rice Punch (BJ), Salted Anchovy Sauce (SA), Jeju Soy Sauce (JSS), and Jeju Soybean Paste (JSP). We found that Latilactobacillus sakei (87.2%), Tetragenococcus halophilus (37.7%), T. halophilus (96.8%), Bacillus subtilis (23.4%), T. halophilus (71.3%), L. sakei (53.7%), Lentibacillus sp. (42.9%), Enterococcus durans (14.6%), and E. durans (32.8%) were the dominant species. Secondly, to study the nine Jeju fermented foods’ anti-inflammatory and anti-melanogenic effects, we employed RAW 264.7 and B16F10 cells, classic cell models for inflammation and melanogenesis studies. Ethyl acetate extracts of the nine Jeju fermented foods all inhibited nitric oxide (NO) and melanin production in a concentration-dependent manner. Thirdly, to test the applicability of the nine Jeju fermented foods to human skin, we used the MTT assay to assess their cytotoxic effects on human keratinocytes (HaCaT cells). Finally, the topical applicability of the nine Jeju fermented foods was tested through primary skin irritation, and it was found that they did not cause any adverse effects. Therefore, extracts from the nine Jeju fermented foods have potential applications as ingredients in anti-inflammatory and anti-melanogenic products and can be used in the cosmetic industry.

ASSESSMENT OF DERMAL IRRITATION OF LAO NHA QUE COCONUT OIL IN EXPERIMENTAL ANIMALS

Lao Nha Que virgin coconut oil (LNQ VCO) is a natural product inteneded to treat some skin diseases such as burns, atopic dermatitis, and xerosis.... To provide information on its local irritation, this study was carried out to evaluate the dermal irritation of LNQ VCO. 0.5 ml of VCO was applied on the skin in one side of the spine while 0.5 ml of distilled water was applied on the other side. After 4-hour exposure period, the residual LNQ VCO was removed and the skin reactions for erythema and oedema was described and scored at 1 hour, 24 hours, 48 hours and 72 hours after removing the patches. The results showed that the erythema appeard on the LNQ VCO-applied skin in two out of three rabbits and recovered up to 72h. The primary irritation index was calculated to catogorize the skin irritation of LNQ VCO. The primary irritation index of LNQ VCO was 0.78. Thus, LNQ VCO might cause slight irritation on the rabbit’s skin.

The whitening efficacy of a compound formula examined using an ultraviolet-induced skin melanization model.

In Eastern culture, a fair complexion is the standard of beauty, leading to appearance-related distress among women with darker skin or facial pigmentation. Women seek whitening cosmetics to enhance their skin tone or correct their pigmentation, but their safety and effectiveness are paramount factors to consider. In this study, we evaluated the safety and whitening effects of a compound formula denoted as TEST comprising astaxanthin, nicotinamide, arbutin, and tranexamic acid. Primary skin irritation and skin-whitening efficacy were examined. Three qualified melanization areas were treated with TEST, 7% ascorbic acid, or a blank. Skin color, the individual type angle (ITA°), and the melanin index (MI) were compared among treatment areas. TEST did not induce a skin response and exhibited a significantly higher ITA° than the blank, while no significant difference was observed with that of 7% ascorbic acid. Furthermore, the MI of TEST was significantly reduced posttreatment. TEST could be integrated into spot-fading and skin-whitening cosmeceuticals or functional cosmetics.

A Dermatological Safety Test of a Face Serum Formulation Derived from Honey and Propolis of Stingless Bee from East Kalimantan

Skincare, which is a type of cosmetics, is an essential component in the process of maintaining and caring for the skin. It is known that the skin quickly absorbs the tiny molecular structure of serum. Stingless bees, widespread in East Kalimantan and Indonesia, benefit the skin's health by producing honey and propolis. This research aims to demonstrate that a face serum derived from honey and propolis of stingless bees from East Kalimantan is safe for use on the skin using dermatological standards. Here we will see whether there are allergic reactions and irritation from using facial serum. Using the Repeated Open Application Test (ROPT) technique, 20 volunteers were subjected to applying a face serum containing honey and stingless bee propolis. The serum was given to the upper arm twice daily for seven days. As part of the test, allergic reactions were evaluated using the system developed by the International Contact Dermatitis Research Group (ICDRG), and irritating reactions were evaluated using the Primary Irritation Index (PII). The results showed that on the first day, four of the volunteers reported moderate irritation reactions. Consequently, they scored 0.7, indicating they suffered minor irritation. On the other hand, the reactions of the remaining 16 volunteers were typical. Twenty participants had normal skin from the second treatment until the seventh day. The overall findings show that the facial serum based on honey and kelulut propolis from stingless bees from East Kalimantan showed a mild irritation reaction at the beginning of use and was safe to use in subsequent uses.

Stability and Safety Analysis of Statin-Loaded Nano-films for the Treatment of Diabetic Wound

Diabetes mellitus (DM) is a metabolic disease that delays the regular stages of the wound's healing process due to delayed inflammatory stages. Due to foot pressure points, chronic foot wounds are ultimately considered the primary cause of lower leg amputation. Diabetic patients have vascular dysfunction and neuropathy, leading to inadequate oxygen supply to the wound area. Statins have a crucial role in the regulation of angiogenesis that could increase vascular endothelial growth factor (VEGF) synthesis. By offering a localized treatment approach while minimizing systemic side effects associated with oral medication, this study aimed to develop statin-loaded nanofilms to determine their stability and safety among healthy individuals as a potential procedure for diabetic wound healing. Simvastatin (SIM) loaded nanofilms formulations (F1-F10) were prepared using the solvent casting method. The formulation was optimized based on tests such as physical appearance, tensile strength, microscopic photographs, morphology, and drug content uniformity. ICH guidelines were followed to determine various parameters (physical appearances, tensile strength, microscopic photographs, morphology, and drug content uniformity) for six-month stability study at three different storage conditions. Safety analysis of the nanofilms was performed on healthy human skin using the Draize skin irritation test. Results showed F7 formulation was considered an optimized formulation as well as stable through the storage period at 4 ± 2°C, 25 ± 2°C, and 40 ± 2 °C. Furthermore, Primary Irritation Index results (PII was 0 showed no irritation in case and control groups) indicate its safety and biocompatibility to skin. Thus, the optimized statin-loaded nanofilm is stable, safe, and non-toxic, which may be used as a potential diabetic wound healing agent.

Formulation Development and Characterization of Acitretin Proniosomal gel: In-vivo Exploration against Imiquimod-induced Psoriasis in Experimental Animals

he main purpose of this study was to prepare and evaluate acitretin proniosomal gel (APG) and find out if the antipsoriatic formulation could prevent Imiquimod (IMQ) induced psoriasis in experimental animals. APG was developed and by coacervation phase separation method. Cholesterol and soya lecithin was used as membrane modifiers and tween 80 and span 60 as non-ionic surfactants. Characterization of the prepared proniosomal gel revealed that the optimized batch APG3 presented excellent formulation characteristics like the viscosity of 9710 ± 1.24 cps, rate of spontaneity as 13 ± 0.86, %entrapment efficiency of 94.91 ± 0.51, average hydrodynamic diameter of niosomes as 345.7 nm, polydispersibility index as 0.159 and ZP of -2.3 mV. In-vivo animal study of the optimized batch APG3 was performed along with biochemical estimations of oxidative parameters as glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase; also, TNF-α, IL-6 were estimated using ELISA sandwiched. Histopathological estimation along with psoriasis area severity index (PASI) scores in the IMQ-induced psoriatic model presented a significant fall in the scoring after treatment with APG3 compared with a psoriatic group. Primary dermal irritation scoring was also evaluated on Sprague Dawley rats. The results presented a considerable decline in skin irritation score compared with a psoriatic group. Also, the levels of GSH, SOD and catalase were increased in APG3 treated group as compared with a psoriatic group. While MDA level is decreased after topical treatment with APG3 compared with a psoriatic group. In conclusion, the optimized APG3 showed promising pharmacological effects in the treatment of psoriasis.

Design and Characterization of Calcipotriol Proniosomal Gel: In-vivo Exploration against Imiquimod-induced Psoriasis in Experimental Animals

The present work focuses on the preparation and evaluation of calcipotriol proniosomal gel (CPG) and find out if the antipsoriatic formulation could prevent imiquimod (IMQ) induced psoriasis in experimental animals. CPG was designed and developed by the coacervation phase separation method. Cholesterol and soya lecithin was used as membrane modifiers and tween 80 and span 60 as non-ionic surfactants. The developed proniosomal gels were characterized which revealed that the optimized batch CPG3 presented excellent formulation characteristics like viscosity of 9690 ± 1.43 cps, rate of spontaneity as 14 ± 1.37, %entrapment efficiency of 82.71 ± 0.48, the average hydrodynamic diameter of niosomes as 739.1 nm, polydispersibility index as 0.360 and ZP of -2.8 mV. In-vivo animal study of the optimized batch CPG3 was performed along with biochemical estimations of oxidative parameters such as glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase; also, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) were estimated using enzyme-linked immunoassay (ELISA) sandwiched. Histopathological estimation along with psoriasis area severity index (PASI) scores in the IMQ-induced psoriatic model revealed a significant decline in the scoring after treatment with CPG3 compared with a psoriatic group. Primary dermal irritation scoring was also evaluated on Sprague Dawley rats. The results revealed a considerable decrease in skin irritation score compared with a psoriatic group. Also, the levels of GSH, SOD and catalase were raised in CPG3 treated group as compared with a psoriatic group. While MDA level was declined after topical treatment with CPG3 compared with a psoriatic group. In conclusion, the optimized CPG3 showed promising pharmacological effects in the treatment of psoriasis

Formulation and Evaluation of Butenafine Hydrochloride-Incorporated Solid Lipid Nanoparticles as Novel Excipients for the Treatment of Superficial Fungal Infections.

The objective of the present study was to develop natural excipient-based solid lipid nanoparticles (SLN) of butenafine hydrochloride (BUTE) using a modified solvent emulsification technique and to evaluate the competence of aloe vera nanolipidgel in enhancing the penetration of BUTE. BUTE-SLNs were prepared using a 23 factorial design to correlate the effect of formulation components on the BUTE-SLN. Particle size, polydispersity index (PDI), zeta potential, entrapment performance, and drug loading were assessed in the formed SLNs. The fabricated BUTE-SLN was evaluated for transmission electron microscopy, fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction study studies and revealed the encapsulation of BUTE in lipid in the amorphous state. BUTE-SLN-based aloe vera gel was formulated and evaluated compared with the marketed product with respect to primary skin irritation, hydration, skin permeation, and antifungal activity. The BUTE-SLN aloe vera gel, optimized for its formulation, features excellent slip properties and controlled drug release. DSC and XRD studies confirm its amorphous nature with effective drug entrapment. The gel provides enhanced skin deposition, improved antifungal activity, and reduced irritation. This makes it a cost-effective and innovative alternative to traditional dosage forms. BUTE-SLN promisingly showed no irritation, higher hydrating potential, slow and sustained release, and enhanced antifungal activity. With an aim to target deeper skin strata, minimize the side effects of drugs and symptomatic impact of fungal infection, and shorten the duration of therapy, BUTE-SLN was successfully prepared. The mean particle size and PDI were 261.25 ± 2.38 nm and 0.268 ± 0.01, respectively. BUTE-SLN gel offers improved topical delivery of BUTE with significantly higher compatibility and antifungal activity than the marketed formulation.

THE EFFECT OF VARIATION CONCENTRATION OF TETRAHYDROHEXAGAMAVUNON-5 (THHGV-5) IN EMULGEL PREPARATION ON ACUTE DERMAL IRRITATION EFFECT AND SUN PROTECTING FACTOR (SPF) VALUE

Objective: A tropical nation experiences intense daytime solar radiation. The likelihood that this condition will result in skin conditions like skin cancer may increase. The skin can be protected as one strategy for coping with this poor potency. Applying various cosmetic products to the skin can provide protection. Due to the antioxidant activity of certain components, various active ingredient types are used in the formulation of those products. A chemical that was created from the structure of curcumin is one of the examples. This substance is referred to as a curcumin analog. THHGV-5 is an analog of curcumin that has strong antioxidant properties. The purpose of this investigation is to ascertain how different Tetrahydropentagamavunon-5 (THHGV-5) concentrations affect the emulgel's sun-protecting factor (SPF) value and irritancy effect. Methods: The three different concentrations of THHGV-5 emulgel are 1.50%, 1.75%, and 2.00%. Then, tests are conducted on the physical qualities (organoleptic, pH, adhesion, dispersiility, and viscosity). The UV spectrophotometric method was used to determine the SPF value of THHGV-5 emulgel in vitro. Regression analysis was used to examine the SPF values from measurements. The acute dermal irritation method was used to measure the Primary Irritation Index (PII) in real-time. The Indonesian Food and Drug Administration's In vivo Non-Clinical Toxicity Test Guidelines are followed by this procedure. PII results were analyzed with Kruskal-Wallis statistical analysis with a 95% confidence level. Results: SPF and PII values will rise as a result of increasing the THHGV-5 content in the formulae. The concentration of THHGV-5 (1.50%, 1.75%, and 2.00%) causes the increase of the SPF values of the formulas (5.76±1.10, 13.03±1.39, and 15.77±0.22) by moderate, maximum, and ultra protection. PII values obtained are significantly different, with a significance level of ≤ 0.05. Conclusion: According to the study's findings, emulgel formulas with higher THHGV-5 concentrations would have higher SPF values and irritant effects. Since a tropical country's SPF recommendation is 15, THHGV-5 with a 2.00% concentration will be able to provide enough protection. However, a study of three different THHGV-5 concentrations (1.50%, 1,75%, and 2.00%) revealed that none of the formulae were skin-safe since they can irritate the skin.

Moxifloxacin loaded microspheres-composed gel for controlled release and enhanced penetration in ocular tissues: In vitro, ex vivo and in vivo proof of concept

Microspheres-enriched ocular gels are proposed in this work for the loading of a model quinolone antibiotic of broad-spectrum - moxifloxacin hydrochloride (MXF) - as an approach to achieve a controlled release profile and enhance drug's bioavailability in ocular milieu. MXF is a synthetic fluoroquinolone antibacterial agent used for treatment of ocular diseases caused by strains of aerobic gram positive and gram-negative bacteria, besides others. MXF-loaded Eudragit RS microspheres were prepared by emulsion solvent evaporation method, as previously described by us. Optimized microspheres were characterized and then formulated in an ocular gel. Hydrophilic polymeric base HPMC K100 was used as gelling agent. Ocular gel enriched with microspheres was evaluated for its physicochemical parameters, in vitro drug release, ex vivo corneal and scleral permeation and bioadhesion, in vivo primary eye irritation and in vivo efficacy study. The developed MXF microspheres dispersed in an ocular gel showed an in vitro drug release over a period 12 h, improved corneal and scleral penetration and increased therapeutic efficacy with a reduced administration frequency which may contribute to increase patient's compliance to ocular treatment.

Optimisation of seed oil and powder of Momordica charantia in the formulation of body scrub cream

Background: Momordica charantia seed oil and powder are potential ingredients for a body scrub. The seeds contain fatty acids to moisturise the skin, and the mineral content to remove dead skin cells and nourish the skin. Objective: To determine the optimal efficiency of Momordica charantia seed oil and powder on body scrub cream produce. Methods: The body scrub used W/O (water-in-Oil) cream base. Simplex Lattice Design was used to determine five formulas. The irritation test with the Draize Skin Test method was carried out on rats (n = three, in each formula), and the Primary Dermal Irritation Index (PDII) was calculated. Informed consent from the female participants has been obtained for the hedonic test. Results: The body scrub cream produced appropriate organoleptic, was not irritating, and was stable after centrifugation and cycling test. The optimum formula contained five grams of oil and one gram of powder with a pH of 5.21; viscosity of 205.33 dPa.s; spreading of 6.12cm; adhesion time of 19.86 seconds; rate of washing of 20.60 seconds; a colour value of 4.04; scent value of 2.90; and texture value of 2.98. Conclusion: The optimised body scrub cream yielded a good formula which can be developed as a body scrub preparation.

Safety evaluation and effects of cascara pulp Gayo Arabica coffee cream as anti-photoaging in animal model.

Prolonged sunlight and ultraviolet (UV) exposure causes premature skin aging called photoaging and coffee-derived topical antioxidants may help to reduce this process. Since a significant amount of antioxidant-rich cascara pulp are wasted in coffee processing, this study aimed to evaluate the safety of cascara extract cream of Gayo Arabica coffee pulp (CECGACP) as anti-photoaging in male Wistar rats (Rattus norvegicus) by assessing the skin primary irritation index (PII), skin macroscopic changes and the level of tumor necrosis factor-alpha (TNF-α). Twenty-five rats were randomly divided into five different groups: negative control (base cream only), positive control containing L-ascorbic acid 3%, and three treatment groups treated with cream containing 5%, 7.5% and 10% of CECGACP. The CECGACP was extracted, formulated into cream as a topical treatment and applied on the backs of the rats two times a day, once before the UV exposure and four hours after the exposure. After four weeks, the skins were macroscopically examined, and the TNF-α levels were measured. The PII was assessed after applying the cream 24 hours before UX exposure. Our data suggested that CECGACP was considered safe because there were no erythema and edema formation on the skin of the rats with PII score of 0 (classified as no irritation or negligible). After UV exposure, all rats had visible wrinkles and erythema on the skin in particular in the first week. After administration of CECGACP, both wrinkles and erythema were decreased. The levels of TNF-α varied from 0.15±0.02 ng/mL in the negative control and CECGACP 7.5% rat groups to 0.19±0.03 in the positive control group; however, there was no significant difference among all the groups. Our study suggests that CECGACP is safe to use in Wistar rats and able to reduce the erythema and edema due to UV exposure. However, the application of CECGACP does not provide a significant reduction of TNF-α levels.

Optimization of 3,4-Dimethoxychalcone and Rutin Containing Gel with Simplex Lattice Design and In Vitro-In Vivo Test as a Sunscreen

3,4-Dimethoxychalcone and rutin, a flavonoid that contains chromophore groups, can absorb UV light and thus can be developed as a sunscreen. The objective of this study was to determine the optimum formula of 3,4-dimethoxychalcone and rutin containing gel, evaluate its physical stability, and activity of 3,4-dimethoxychalcone and rutin gel as a sunscreen through in vitro and in vivo tests. HPMC, CMC-Na, and methylcellulose were formulated into a gel base to obtain good adhesion and a clear appearance gel. Simplex Lattice Design (SLD) with Design Expert software version 10 was utilized to determine the optimum gel formulation. UVA-PF protection, photostability with transpore method, and acute dermal irritation test were performed to evaluate sunscreen activity of 3,4-dimethoxychalcone and rutin gel. The data were analyzed using SPSS version 25. The results showed that the optimum formula for 3,4-dimethoxychalcone-rutin gel consisted of 1.5% HPMC, 1.8% CMC-Na and 0.6% methylcellulose, which showed a pH of 6.96, viscosity of 89.10 dpa.s, and spreadability of 16.30 cm2. The pH, viscosity, and spreadability of base and 3,4-dimethoxychalcone- rutin gel was stable for 4 weeks of storage. The UVA-PF value is 6.48 which according to the FDA is included in the category of a two star (**) sunscreen label. The sunscreen did not exhibit a shift in wavelength after 6 hours of irradiation. Based on the primary irritation test, 3,4-dimethoxychalcone- rutin sunscreen produced zero (0) erythema and edema index. Thus, it did not cause irritation to the skin of experimental animals. Therefore, the gel containing 3,4-dimethoxychalcone and rutin had potential as a sunscreen product based on in vitro-in vivo tests and was safe on animal skin.

The Use of an Ambroxol Solution to Assess Acute Dermal Irritation on Rabbit Skin

Ambroxol can overcome infections due to the presence of biofilms in the body by interfering with the formation of sticky biofilms and reducing biofilm production, so it has the potential to be used in topical preparations for the treatment of infections. This study aimed to measure the irritating effect on the skin of rabbits resulting from the ambroxol solution to assess the safety of the ambroxol solution. The methods refers to BPOM 2020, namely by dabbing 0.5 ml of ambroxol solution on the back skin of rabbits, then covering it with gauze and non-irritant plasters, after 4 hours of cleaning of residues is then observed at 1 , 24, 48 and 72 hours to see whether or not there was an effect of erythema and edema arising from the influence of the experiment, and at the end of the investigation, a histopathological test was carried out. The results of the research are Macroscopically the ambroxol solution did not show any erythema and edema, so the primary irritation index score was obtained for all test solutions with a score of 0. In contrast, in the microscopic irritation test, the score for erythema was 4 and for edema was 3. . From this research, it can be concluded that the ambroxol solution non-irritating to the skin.
 
 KEYWORDS: Biofilm, ambroxol solutions, acute irritation test.
 

Activity and Safety of Cinchonine Nanostructured Lipid Carriers as a Hair Growth Stimulant in Mice Model of Androgenetic Alopecia

Androgenetic alopecia (AA) is a hair growth disorder characterized by hair loss and miniaturization of the size of follicles and dermal papillae. Cinchonine is a quinoline alkaloid that can increase VEGF production and potential as a hair growth stimulant. This study aimed to determine the morphology, penetration (in vitro), as well as safety and activity of cinchonine nanostructured lipid carriers (CN-NLC) serum as a hair growth stimulant. Preparation of CN-NLC serum using a combination of micro-emulsification and ultra-sonification methods, characterization of CN-NLC serum included morphology and closed hair follicle diffusion methods. Dermal and eye irritation test using New Zealand rabbit strain with primary irritation index parameters. Hair growth stimulant activity test using Swiss Webster mice strain, induced with the hormone testosterone. Observations were performed at 7, 14, and 21 days with hair length and histology parameters. CN-NLC serum morphology is a spherical shape with size ±500 nm, diffusion of serum CN-NLC (open hair follicles) of 23.92±0.84%; (close hair follicles) of 11.37±2.29%; and CN solution of 6.00±0.72%. CN-NLC serum are non-irritant with a primary irritation index of 0.0. Activity tests showed hair length on days 7; 14 and 21 were increased by 20.24-23.74%; 33.47-36.43%, and 39.30-39.97% (P≤0.05). Histological data showed an increase in the number and size of both dermal papillae and hair follicles compared to the control group. CN-NLC serum can improve the penetration of CN into hair follicles. CN-NLC serum is safe and effective as a hair growth stimulant in the treatment of AA.

The Effects of 2'-Hydroxy-3,6'-Dimethoxychalcone on Melanogenesis and Inflammation.

In this study, we demonstrated that 2'-hydroxy-3,6'-dimethoxychalcone (3,6'-DMC) alleviated α-MSH-induced melanogenesis and lipopolysaccharides (LPS)-induced inflammation in mouse B16F10 and RAW 264.7 cells. In vitro analysis results showed that the melanin content and intracellular tyrosinase activity were significantly decreased by 3,6'-DMC, without cytotoxicity, via decreases in tyrosinase and the tyrosinase-related protein 1 (TRP-1) and TRP-2 melanogenic proteins, as well as the downregulation of microphthalmia-associated transcription factor (MITF) expression through the upregulation of the phosphorylation of extracellular-signal-regulated kinase (ERK), phosphoinositide 3-kinase (PI3K)/Akt, and glycogen synthase kinase-3β (GSK-3β)/catenin, and downregulation of the phosphorylation of p38, c-Jun N-terminal kinase (JNK), and protein kinase A (PKA). Furthermore, we investigated the effect of 3,6'-DMC on macrophage RAW264.7 cells with LPS stimulation. 3,6'-DMC significantly inhibited LPS-stimulated nitric oxide production. 3,6'-DMC also suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 on the protein level. In addition, 3,6'-DMC decreased the production of the tumor necrosis factor-α and interleukin-6. Successively, our mechanistic studies revealed that 3,6'-DMC also suppressed the LPS-induced phosphorylation of the inhibitor of IκBα, p38MAPK, ERK, and JNK. The Western blot assay results showed that 3,6'-DMC suppresses LPS-induced p65 translocation from cytosol to the nucleus. Finally, the topical applicability of 3,6'-DMC was tested through primary skin irritation, and it was found that 3,6'-DMC, at 5 and 10 μM concentrations, did not cause any adverse effects. Therefore, 3,6'-DMC may provide a potential candidate for preventing and treating melanogenic and inflammatory skin diseases.

Syringetin Promotes Melanogenesis in B16F10 Cells.

Syringetin, an active compound present in red grapes, jambolan fruits, Lysimachia congestiflora, and Vaccinium ashei, is a dimethyl myricetin derivative which contains free hydroxyl groups at the C-2' and C-4' positions in ring B. Recent studies have revealed that syringetin possesses multiple pharmacological properties, such as antitumor, hepatoprotective, antidiabetic, antioxidative, and cytoprotective activities. To date, there has been no attempt to test the action of syringetin on melanogenesis. In addition, the molecular mechanism for the melanogenic effects of syringetin remains largely unknown. In this study, we investigated the effect of syringetin on melanogenesis in a murine melanoma cell line from a C57BL/6J mouse, B16F10. Our results showed that syringetin markedly stimulated melanin production and tyrosinase activity in a concentration-dependent manner in B16F10 cells. We also found that syringetin increased MITF, tyrosinase, TRP-1, and TRP-2 protein expression. Moreover, syringetin inhibited ERK and PI3K/Akt phosphorylation by stimulating p38, JNK, PKA phosphorylation levels, subsequently stimulating MITF and TRP upregulation, resulting in the activation of melanin synthesis. Furthermore, we observed that syringetin activated phosphorylation of GSK3β and β-catenin and reduced the protein level of β-catenin, suggesting that syringetin stimulates melanogenesis through the GSK3β/β-catenin signal pathway. Finally, a primary skin irritation test was conducted on the upper backs of 31 healthy volunteers to determine the irritation or sensitization potential of syringetin for topical application. The results of the test indicated that syringetin did not cause any adverse effects on the skin. Taken together, our findings indicated that syringetin may be an effective pigmentation stimulator for use in cosmetics and in the medical treatment of hypopigmentation disorders.

6-Methylcoumarin Promotes Melanogenesis through the PKA/CREB, MAPK, AKT/PI3K, and GSK3β/β-Catenin Signaling Pathways.

We investigated the effects of four coumarin derivatives, namely, 6-methylcoumarin, 7-methylcoumarin, 4-hydroxy-6-methylcoumarin, and 4-hydroxy-7-methylcoumarin, which have similar structures on melanogenesis in a murine melanoma cell line from a C57BL/6J mouse called B16F10. Our results showed that only 6-methylcoumarin significantly increased the melanin synthesis in a concentration-dependent manner. In addition, the tyrosinase, TRP-1, TRP-2, and MITF protein levels were found to significantly increase in response to 6-methylcoumarin in a concentration-dependent manner. To elucidate the molecular mechanism whereby 6-methylcoumarin-induced melanogenesis influences the melanogenesis-related protein expression and melanogenesis-regulating protein activation, we further assessed the B16F10 cells. The inhibition of the ERK, Akt, and CREB phosphorylation, and conversely, the increased p38, JNK, and PKA phosphorylation activated the melanin synthesis via MITF upregulation, which ultimately led to increased melanin synthesis. Accordingly, 6-methylcoumarin increased the p38, JNK, and PKA phosphorylation in the B16F10 cells, whereas it decreased the phosphorylated ERK, Akt, and CREB expressions. In addition, the 6-methylcoumarin activated GSK3β and β-catenin phosphorylation and reduced the β-catenin protein level. These results suggest that 6-methylcoumarin stimulates melanogenesis through the GSK3β/β-catenin signal pathway, thereby affecting the pigmentation process. Finally, we tested the safety of 6-methylcoumarin for topical applications using a primary human skin irritation test on the normal skin of 31 healthy volunteers. We found that 6-methylcoumarin did not cause any adverse effects at concentrations of 125 and 250 μM. Our findings indicate that 6-methylcoumarin may be an effective pigmentation stimulator for use in cosmetics and the medical treatment of photoprotection and hypopigmentation disorders.