In vitro approaches to antioxidant screening for the development of a sunscreen formulation

Abstract The incorporation of antioxidants into sunscreens may provide additional skin photoprotection against the harmful photobiological effects of ultraviolet radiation. The present study evaluated the applicability of a screening approach to the assessment of the antioxidant and photoprotective properties of vitamin C, vitamin E, and coenzyme Q10 and then determined the performance of the most effective antioxidant in a sunscreen formulation. Antioxidant activity was assessed by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2`-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, and oxygen radical absorbance capacity (ORAC) assay, and the photoprotective potential was investigated by the yeast photoprotection assay. The antioxidant with the best effect was incorporated into sunscreen formulations which were evaluated for 120 days regarding their in vitro photoprotective parameters. Vitamin C showed high antioxidant capacity as well as a photoprotective potential against simulated solar irradiation applied for times longer than 1 h. Although the Sun Protection Factor, UVA/UVB ratio and critical wavelength did not differed significantly (p<0.05) between the formulation blank and the formulations containing 0.5% or 1% vitamin C, formulations with vitamin C kept their photostability for 6 months. Consequently, the proposed screening approach seems to be promising for the development of an antisolar photostable formulation containing vitamin C as an antioxidant.

Heteroisotherapics effect on the treatment against smoking: a cognitive-behavioral approach

The most common way of consuming nicotine is in tobacco cigarettes. Nicotine causes intense addiction. The National Cancer Institute coordinates and executes the Tobacco Control Program in Brazil, through actions that encourage the adoption of healthier lifestyles. In this context, homeopathy has used Heteroisotherapic medicines formulated according to the homeopathic pharmaceutical technology with scientific evidence of efficacy in the detoxification of substances and metals, and in the desensitization of foods or medicines. Aims Promote the importance of the cognitive-behavioral approach in combination with the homeopathic treatment against smoking. Methodology In the initial phase of the randomized double-blind clinical study (CEP / HUCFF / UFRJ 65622916.2.0000.5257), the effectiveness of the 6CH heteroisotherapeutic drug was assessed. Volunteers were recruited andin-person welcoming meetings, using the cognitive-behavioral approach, were carried out to inform them about the risks of smoking and the benefits of quitting. In addition, they were supported and guided during the smoking cessation process so that they could deal with the withdrawal syndrome, the psychological dependence and the constraints associated with smoking. Results and discussion84 participants were selected according to the inclusion criteria, and divided by randomization into two groups:the Test Group (heteroisotherapeutic medication) and the Control Group (homeopathic medication Nux vomica6CH).Both groups will be followed for 12 months. The combination of the following approaches has led to a significant increase in the cessation rate: I.Prepare the smoker for solving his own issues; II. Stimulate skills to resist temptations to smoke; III. Prepare to prevent relapse; IV. Prepare to deal with stress. Studies show that, regardless the duration of these approaches, there is an increase in the abstinence rate. Moreover, the longer the total approach time (frequency multiplied by the time spent on each contact), the higher the abstinence rate. On the other hand, from a total approach time of 90 minutes on, there is no further increase in the abstinence rate. ConclusionThe partial results obtained so far demonstrate that the cognitive-behavioral approach played a decisive role in the groups performance, favoring the treatment adherence as well as the group cohesion around the Project's objective, contributing to the effectiveness of the medicine, a decreased anxiety, improved sleep, cessation or decrease in the number of cigarettes smoked per day and the abstinence rate.

Evaluation of the genotoxic and mutagenic potentials of phytotherapic and homeopathic solutions of Euphorbia tirucalli Lineu (Aveloz) / Evaluation of the genotoxic and mutagenic potentials of phytotherapic and homeopathic solutions of Euphorbia tirucalli Lineu (Aveloz)

Introduction: Euphorbia tirucalli Lineu, commonly known as Aveloz, is a very common plant found in tropical regions [1]. The ingestion or contact with its latex causes symptoms such as vomiting and diarrhea, pallor, skin irritation, hepatotoxicity as well as carcinogenesis [2]. Moreover, the Aveloz latex is also responsible for a few important activities against some infectious and neoplastic diseases. Aveloz latex phytochemical composition may vary according to seasonal aspects and geographic location [3], and it is used either orally or topically in traditional medicine. Popularly known as an antitumoral agent (breast, prostate, lung, kidney), it is used not only in Brazil, but in several other countries. According to the literature, the latex could have a dual behaviour, activating or inhibiting tumoral events [3-6]. However, there are few reports discussing these mechanisms. Besides, the mutagenic and genotoxic potentials of phytochemical and homeopathic Aveloz have not yet been described. Several experimental methods have been used to evaluate the mutagenic and genotoxic effects, such as Inductest, the Ames test and the chromotest. Objective: This study aims to evaluate the genotoxic and mutagenic potentials of Aveloz latex and Aveloz phytotherapic and homeopathic solutions. Methodology: In this study, Aveloz 5 and 30cH are prepared according to Brazilian Homeopathic Pharmacopoeia [7], from Aveloz latex collected in the Center for Natural Products Research (NPPN) at the Universidade Federal do Rio de Janeiro [8]. The Aveloz phytochemical solution was prepared following the doses used in folk medicine: 2 drops diluted in 250ml of water and 2 drops diluted in 25 ml of water. All test solutions were submitted to the following methodologies: (a) Inductest: assesses the ability of physical or chemical agents to promote lysogenic induction as a response to DNA damage in lysogenic bacteria; (b) The Ames test: uses indicator strains of Salmonella typhimurium, which are sensitive to substances that can induce different types of mutation; (c) Chromotest: evaluates the genotoxicity of chemicals through the induction of the bacterial SOS system. Results: In the Inductest there was no decrease in bacterial survival fraction and no increase in lysogenic cycle. As measured by The Ames test and the chromotest no mutagenic or genotoxic potentials were detected. Discussion: The homeopathic and the phytochemical Aveloz solutions were unable to produce lysogenic induction or mutagenesis in bacterial cells and they were also unable to produce genotoxic effects, as measured by chromotest. Conclusion: Our results showed that no mutagenic or genotoxic damages were induced by all Aveloz preparations studied, thus we are led to believe that patients using Aveloz as a complementary therapy present no side effects in relation to mutagenesis and genotoxicity.