Aim, Materials and Methods – Anti Acne efficacy – PG6 ACTIVE AA-BET C®
It is an active of Socri – Greengredients® called PG6 ACTIVE AA-BET C® (POLYGLYCERYL-6, AZELAIC ACID, BETAINE) which has been added at 2% in an emulsion with the composition (INCI): Aqua, Paraffinum Liquidum, Glyceryl Stearate, Cetearyl Alcohol, Glycerin, Cetyl Alcohol, Polyglyceryl-6, Azelaic Acid, Betaine, Ceteareth-20, Phenoxyethanol, Dimethicone, Stearamidopropyl Dimethylamine, Citric Acid, Sodium Dehydroacetate, Benzoic Acid, Lecithin, Dehydroacetic Acid, Ethylhexylglycerin, Tocopherol, Ascorbyl Palmitate.
For this study, 20 volunteers were enrolled, of both sexes, aged between 18 and 45 who had mild to moderate facial acne caused by the presence of a maximum of 20 comedones and 50 papules and pustules and the absence of nodules or cysts (Cunliffe 2001). Patients with a history of using anti-acne medications in the month before the trial were rejected. During the test the volunteers did not use other products for the treatment of acne, to avoid a possible overlap of effects.
Effectiveness in improving acne was assessed instrumentally by measuring the amount of cutaneous sebum, pH, papular erythema through the sensors of a Multiprobe Adapter System MPA5 of Courage & Khazaka Electronic GmbH (Cologne, Germany) and the quantity of injury by performing digital photography with a Canon G12 camera. Moreover, a subjective clinical evaluation was carried out by the dermatologist, for the counting of lesions and safety parameters after application of the product and was carried out self-evaluation test on the pleasantness and effectiveness of the tested product.
SEBOMERIC INDEX EVALUATION
The sebometric index was evaluated using the sebumeter method that has been the most widely used method for more than 25 years to accurately and reproducibly determine the level of sebum in the skin surface as well as in the scalp. It directly measures the level of lipids present on the skin surface. The principle of the method used is photometric. A special opaque tape, in a particular cartridge applicator, rests on a delimited area of the skin surface, from which it absorbs the superficial sebum and becomes all the more transparent the more abundant the sebum is. The tape is then inserted into a photocell instrument: a light beam is passed through the tape, reflected on the mirror placed in the cartridge on the back of the tape and is picked up by the receiving probe. The intensity of the radius will be greater the more transparent the tape and therefore the amount of sebum absorbed. The data are displayed on the computer and are expressed in micrograms of sebum/cm2 and derive from a comparison between the initial transparency of the tape (measured before contact with the skin) and the values after application on the skin. For each measure a strip section of 64 mm2 is used. A trigger located on one side of the tape cassette allows access to a new measurement. The used ribbon is rewound in the cassette. The life of the cassette is around 450 measurements. For reasons of hygiene, when the tape is applied in its entirety, only the cassette is replaced.The values found can be very different depending on the area of the face, and in general they are higher in the so-called “T zone” that includes the front, nose and chin, richer in sebaceous glands. The lateral areas of the face (high and low cheekbones, cheek and external eye contour), less rich in sebaceous glands and less induced by hormonal stimuli secrete less sebum and have lower sebometric values.
SOOTHING ACTIVITY EVALUATION
The effect on the reduction of redness was evaluated using the Mexameter MX 18 probe (Courage + Khazaka Electronic GmbH). This probe has a hole of about 4 mm in diameter. Four measurements were taken, at the corners of an area bounded with tape, for each volunteer expressed in units of hemoglobin (parameter E) where the minimum value corresponds to 500.
The principle of measurement of skin reddening is based on a source of light, with three specific wavelengths, whose radiation is absorbed by the skin and diffusely reflected. A sensor analyzes the reflection diffused by the skin. If the skin is well vascularized, the hemoglobin value is also increased.
As a result, stimulation of microcirculation can be assessed before and after topical application with hemoglobin measurement. The same measurement probe is used in addition to quantify the reddening of the skin (erythema) also determine the degree of tanning of the skin (melanin).
The measurement of the pH level on the skin surface is an important parameter to assess the quality of the skin. hydrolipidic film and the changes it may undergo following application on the skin especially of soaps, detergents or cosmetic products.
All measurements were made with a PH 905 Skin-pH-Meter probe (Courage + Khazaka Electronic GmbH). This is an electrode-probe consisting of a glass rod containing all the sensor elements. The planar design of the probe head allows direct measurement on the skin. Measurement is initiated by pressing a button on the side of the probe handle and the result is immediately displayed up to two decimal places. The short measurement time prevents occlusive effects on the skin. The accuracy of the device can be easily controlled at any time through a calibration system.
Through the clinical examination and the use of macro photography, performed by the investigator dermatologist, acneic lesions on one side of the face were used as parameters: papules, pustules and comedones. These were counted and for each parameter, the totals of the scores for each considered lesion were calculated, in all study times. The total count of the lesions (TLC) was also used to determine the effectiveness of the treatment on the severity of the acne.
TLC was calculated as: TLC = papules + pustules + comedones.
The product has been used according to its usage characteristics: applying it twice a day by passing the appropriate tube applicator on previously washed acneic lesions. Its effectiveness was assessed with a 30-day Long Term Test. The area used for the test was one side of the face chosen randomly for each volunteer. Before the measurements all the subjects remained for 30 minutes in the clinic, to acclimatize the skin to the temperature and humidity of the air-conditioned room where the tests were carried out. Before the t0 (baseline value) each volunteer was asked not to cleanse the face, for at least 3 hours before the experiment. After this period, the baseline sebumometry was measured on healthy skin, pHmetria on healthy skin, colorimetry on 1 or more papules, a clinical visit with an account of acne lesions and macrophotography.
The experimenters performed the instrumental tests by working for each probe three measurements – in contiguous healthy areas or on different inflamed lesions – then calculating the mean. The analyzed areas were always the same, in different times, for each volunteer.
The same instrumental and clinical evaluations were carried out after 15 days (t15d) and 30 days (t30d) of continuous application of the product. After the baseline values were recorded for the volunteers, the product to be applied at home was delivered. At each study time a dermatological examination was performed to evaluate any side effects.
All results were compared, with baseline measurement at each time, using the Student’s t test for paired data or a non-parametric test (Wilcoxon signed rank test) when the difference in averages did not show the characters of normality verified using the Shapiro- Wilk test. The results were considered significant if p <0.05 (95% Confidence Level) and were calculated using a Microsoft® Excel spreadsheet. All data were presented as mean ± standard deviation and in addition to the measured value they were also reported as differences vs. baseline (difference and percentage value).