RESUMO
OBJECTIVE: The harmful effects induced by ultraviolet exposition and the significant increment in skin cancer diagnosis confirm the necessity to develop effective and safe sunscreens. Limited efficacy and cutaneous adverse reactions of traditional formulations drove the incorporation of natural extracts into multifunctional sunscreens. Vaccinium myrtillus L. extract (VME), that contains anthocyanins and flavonoids, is a potential candidate for such systems. METHODS: Considering that, we performed in vitro and in vivo tests to evaluate the sun protection factor (SPF), photostability, and safety of sunscreen samples containing VME. RESULTS: As main results, the SPF was reduced in both in vitro and in vivo evaluation in the presence of VME; nonetheless, the samples were photostable and safe. CONCLUSION: Further investigation is required to better understand the unexpected effects of VME over photoprotection, decreasing the SPF value. As a conclusion, even with interesting findings, we highlight the importance of case-by-case investigations to develop multifunctional bioactive sunscreens.
Assuntos
Protetores Solares , Vaccinium myrtillus , Humanos , Protetores Solares/efeitos adversos , Antocianinas/efeitos adversos , Raios Ultravioleta/efeitos adversos , Pele , Extratos Vegetais/efeitos adversosRESUMO
The solar radiation range has harmful and beneficial effects. Sunscreens, which selectively block specific spectral regions, may potentially interfere with skin homeostasis. For instance, the ultraviolet (UV) B waveband produces erythema and DNA damage; simultaneously, it induces pre-vitamin D3 synthesis. UVA1 and visible light can both induce pigmentation in skin phototypes IV-VI, and act in synergy to induce erythema and persistent pigment darkening. In contrast, UVA may contribute to blood pressure control and cardioprotection by inducing release of nitric oxide from intracutaneous photolabile nitric oxide derivatives. Finally, infrared A radiation alters the collagen equilibrium of the dermal extracellular matrix but is involved in the regulation of body temperature and in nitric oxide release, with a potential beneficial impact on blood pressure regulation. Ideally, photoprotection should thus be performed with a neutral density filter, mitigating all radiation ranges homogeneously, to maintain solar spectrum homeostasis. Natural compounds such as mycosporine-like amino acids are promising natural UV radiation-filtering compounds for an improved homeostasis with our environment. Lastly, we should not forget individual characteristics and behavior, as homeostasis differs according to individual phototypes and skin exposure behaviors.
Assuntos
Homeostase/efeitos dos fármacos , Pigmentação da Pele/efeitos dos fármacos , Pele/metabolismo , Protetores Solares/administração & dosagem , Administração Cutânea , Variação Biológica da População , Homeostase/efeitos da radiação , Humanos , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Pigmentação da Pele/efeitos da radiação , Luz Solar/efeitos adversos , Protetores Solares/efeitos adversos , Raios Ultravioleta/efeitos adversos , Vitamina D/biossínteseRESUMO
BACKGROUND: Photoallergic contact dermatitis (PACD) to oxybenzone was reported for the first time in 1980. Oxybenzone is the most common photoallergen in the United States and Canada and the fourth most common .in Europe. There are no studies or data on the prevalence of oxybenzone PACD in Argentina. OBJECTIVE: To determine the proportion of photosensitive patients with PACD to oxybenzone. METHODS: We conducted a descriptive cross-sectional study of 35 patients with photosensitivity reactions confirmed by photopatch testing at the Research Center of Hospital Público San Martín in La Plata, Argentina, in 2015 and 2016. RESULTS: PACD was identified in 6 patients (17.14%). Five of these (14.28%) had at least one positive reaction to oxybenzone in the photopatch test; 4 had a reaction at irradiated sites only (5 J/cm2 UVA) and one had a reaction at both irradiated and nonirradiated sites. CONCLUSIONS: PACD to sunscreens containing oxybenzone is common and is probably underdiagnosed due to a lack of confirmation by photopatch tests or other diagnostic tools. Sensitization rates vary according to region and are influenced by sunscreen ingredients and variations in the use of sunscreen products, cosmetics, and topical drugs.
Assuntos
Benzofenonas/efeitos adversos , Dermatite Fotoalérgica/epidemiologia , Dermatite Fotoalérgica/etiologia , Protetores Solares/efeitos adversos , Adulto , Idoso , Argentina/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
The use of sunscreen is a key component of public health campaigns for skin cancer prevention, but epidemiological studies have raised doubts on its effectiveness in the general population. This systematic review and meta-analysis aimed to assess the association between risk of skin cancer and sunscreen use. We searched PubMed, BIREME and Google Scholar from inception to May 17, 2017, to identify observational studies and controlled trials. We used a random-effects model for conventional and cumulative meta-analyses. We included 29 studies (25 case-control, two cohort, one cross-sectional, and one controlled trial) involving 313,717 participants (10,670 cases). The overall meta-analysis did not show a significant association between skin cancer and sunscreen use (odds ratio (OR) = 1.08; 95% CI: 0.91-1.28, I2 = 89.4%). Neither melanoma (25 studies; 9,813 cases) nor non-melanoma skin cancer (five studies; 857 cases) were associated with sunscreen use, with a pooled OR (95% CI) of 1.10 (0.92-1.33) and 0.99 (0.62-1.57), respectively. The cumulative evidence before the 1980s showed a relatively strong positive association between melanoma and sunscreen use (cumulative OR: 2.35; 95% CI: 1.66-3.33). The strength of the association between risk of skin cancer and sunscreen use has constantly decreased since the early 1980s, and the association was no longer statistically significant from the early 1990s. While the current evidence suggests no increased risk of skin cancer related to sunscreen use, this systematic review does not confirm the expected protective benefits of sunscreen against skin cancer in the general population.
Assuntos
Melanoma/epidemiologia , Neoplasias Cutâneas/epidemiologia , Protetores Solares/administração & dosagem , Adulto , Criança , Estudos Transversais , Geografia Médica , Humanos , Melanoma/etiologia , Estudos Observacionais como Assunto , Razão de Chances , Neoplasias Cutâneas/etiologia , Protetores Solares/efeitos adversosRESUMO
The goal of this research was to identify major compounds of the aerial parts of M. parvifolia (Benth.) Parra-Os., that could enhance its possible application as additive in dermocosmetic products, as well as evaluate the antioxidant properties. The extracts agreed with the broad-spectrum UVB/UVA absorption detected and could act as broad-spectrum sunscreens, covering the UVA and UVB range. Methanolic extracts showed an important antiradical capacity (0.46 and 0.47 g/µmol DPPH), TPC (37.58 and 51.41mg GAE/g DS) and TAC (1.12 and 3.31 mg C3GE/g DS) in fruits and leaves, respectively. M. parvifolia could be considered as a prospective source of natural UV-radiation absorbers with antioxidant capacity. Although the results have clearly demonstrated the potential photoprotection capacity, more studies are needed to enhance its application as an additive in pharmaceutical and medicinal formulations.
Assuntos
Raios Ultravioleta/efeitos adversos , Extratos Vegetais , Myricaceae/classificação , Absorção , Protetores Solares/efeitos adversos , Técnicas In Vitro/instrumentação , Componentes Aéreos da Planta , Aditivos em Cosméticos , AntioxidantesAssuntos
Alérgenos/análise , Cosméticos/análise , Fármacos Dermatológicos/análise , Brasil , Cosmecêuticos/efeitos adversos , Cosmecêuticos/análise , Cosmecêuticos/química , Cosméticos/efeitos adversos , Cosméticos/química , Dermatite Alérgica de Contato/etiologia , Fármacos Dermatológicos/efeitos adversos , Fármacos Dermatológicos/química , Humanos , Sabões/efeitos adversos , Sabões/análise , Sabões/química , Protetores Solares/efeitos adversos , Protetores Solares/análise , Protetores Solares/químicaRESUMO
Si bien los niveles bajos de vitamina D se han asociado con varios resultados de interés en salud, aún resulta motivo de controversia qué significa un nivel bajo, cual es la utilidad de su suplementación y cuales son sus potenciales efectos adversos. En ese contexto, se realizó en el Servicio de Medicina Familiar y Comunitaria del Hospital Italiano un taller de discusión denominado "Actividad ECCO" (Evidencia Científica en la Clínica Cotidiana) en la que fueron presentados los resulta-dos de estudios identificados que hubieran comparado el uso de vitamina D (con o sin suplementación de calcio) ver-sus placebo, con el objetivo de discutir cuál es la evidencia actual para el rastreo de deficiencia de vitamina D y para, eventualmente, recomendar o no su suplementación. Este artículo resume la evidencia identificada y las conclusiones consensuadas en dicha actividad. (AU)
Although low levels of vitamin D have been associated with several health outcomes, it is controversial what a low level means, the usefulness of its supplementation and its potential adverse effects. In this context, a workshop called "ECCO Activity" (Scientific Evidence in the Daily Clinic) was held in the Family and Community Medicine Division of Hospital Italiano de Buenos Aires, where the results of identified studies that compared the use of vitamin D (with or without calcium supplementation) versus placebo, with the aim of discussing what is the current evidence for screening of vitamin D deficiency and to, eventually, recommend or not its supplementation. This article summarizes the identified evidence and the agreed conclusions in that activity. (AU)
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Deficiência de Vitaminas/diagnóstico , Vitamina D/efeitos adversos , Osteoporose/tratamento farmacológico , Insuficiência Pancreática Exócrina/complicações , Fenobarbital/efeitos adversos , Fenitoína/efeitos adversos , Protetores Solares/efeitos adversos , Vitamina D/administração & dosagem , Vitamina D/sangue , Vitamina D/uso terapêutico , Acidentes por Quedas/prevenção & controle , Acidentes por Quedas/estatística & dados numéricos , Biomarcadores , Derivação Gástrica/efeitos adversos , Doenças Inflamatórias Intestinais/complicações , Doença Celíaca/complicações , Cálcio/administração & dosagem , Cálcio/uso terapêutico , Risco , Corticosteroides/efeitos adversos , Síndrome do Intestino Irritável/complicações , Antirretrovirais/efeitos adversos , Insuficiência Hepática/complicações , Insuficiência Renal Crônica/complicaçõesRESUMO
BACKGROUND: 'Keratinocyte cancer' is now the preferred term for the most commonly identified skin cancers basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), which were previously commonly categorised as non-melanoma skin cancers (NMSC). Keratinocyte cancer (KC) represents about 95% of malignant skin tumours. Lifestyle changes have led to increased exposure to the sun, which has, in turn, led to a significant increase of new cases of KC, with a worldwide annual incidence of between 3% and 8%. The successful use of preventive measures could mean a significant reduction in the resources used by health systems, compared with the high cost of the treatment of these conditions. At present, there is no information about the quality of the evidence for the use of these sun protection strategies with an assessment of their benefits and risks. OBJECTIVES: To assess the effects of sun protection strategies (i.e. sunscreen and barrier methods) for preventing keratinocyte cancer (that is, basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC) of the skin) in the general population. SEARCH METHODS: We searched the following databases up to May 2016: the Cochrane Skin Group Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trial registries and the bibliographies of included studies for further references to relevant trials. SELECTION CRITERIA: We included randomised controlled clinical trials (RCTs) of preventive strategies for keratinocyte cancer, such as physical barriers and sunscreens, in the general population (children and adults), which may provide information about benefits and adverse events related to the use of solar protection measures. We did not include trials focused on educational strategies to prevent KC or preventive strategies in high-risk groups. Our prespecified primary outcomes were BCC or cSCC confirmed clinically or by histopathology at any follow-up and adverse events. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies for eligibility using Early Review Organizing Software (EROS). Similarly, two review authors independently used predesigned data collection forms to extract information from the original study reports about the participants, methods of randomisation, blinding, comparisons of interest, number of participants originally randomised by arm, follow-up losses, and outcomes, and they assessed the risk of bias. We resolved any disagreement by consulting a third author and contacted trial investigators of identified trials to obtain additional information. We used standard methodological procedures expected by Cochrane. MAIN RESULTS: We included one RCT (factorial design) that randomised 1621 participants.This study compared the daily application of sunscreen compared with discretionary use of sunscreen, with or without beta-carotene administration, in the general population. The study was undertaken in Australia; 55.2% of participants had fair skin, and they were monitored for 4.5 years for new cases of BCC or cSCC assessed by histopathology. We found this study to be at low risk of bias for domains such as allocation, blinding, and incomplete outcome data. However, we found multiple unclear risks related to other biases, including an unclear assessment of possible interactions between the effects of the different interventions evaluated (that is, sunscreen and beta-carotene). We found no difference in terms of the number of participants developing BCC (n = 1621; risk ratio (RR) 1.03, 95% confidence interval (CI) 0.74 to 1.43) or cSCC (n = 1621; RR 0.88, 95% CI 0.50 to 1.54) when comparing daily application of sunscreen with discretionary use, even when analyses were restricted to groups without beta-carotene supplementation. This evidence was of low quality, which means that there is some certainty that future studies may alter our confidence in this evidence.We reported adverse events in a narrative way and included skin irritation or contact allergy.We identified no studies that evaluated other sun protection measures, such as the use of sun-protective clothing, sunglasses, or hats, or seeking the shade when outdoors. AUTHORS' CONCLUSIONS: In this review, we assessed the effect of solar protection in preventing the occurrence of new cases of keratinocyte cancer. We only found one study that was suitable for inclusion. This was a study of sunscreens, so we were unable to assess any other forms of sun protection. The study addressed our prespecified primary outcomes, but not most of our secondary outcomes. We were unable to demonstrate from the available evidence whether sunscreen was effective for the prevention of basal cell carcinoma (BCC) or cutaneous squamous cell carcinoma (cSCC).Our certainty in the evidence was low because there was a lack of histopathological confirmation of BCC or cSCC in a significant percentage of cases. Amongst other sources of bias, it was not clear whether the study authors had assessed any interaction effects between the sunscreen and beta-carotene interventions. We think that further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Assuntos
Carcinoma Basocelular/prevenção & controle , Carcinoma de Células Escamosas/prevenção & controle , Neoplasias Induzidas por Radiação/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Luz Solar/efeitos adversos , Protetores Solares/administração & dosagem , Adulto , Austrália , Criança , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Protetores Solares/efeitos adversos , Raios Ultravioleta/efeitos adversos , Vitaminas/administração & dosagem , Vitaminas/efeitos adversos , beta Caroteno/administração & dosagem , beta Caroteno/efeitos adversosRESUMO
Currently most of sunscreens provide effective protection in the full UV range but lack VIS protection. The addition of effective antioxidants to sunscreens might afford suitable UV-VIS protection. Apigenin (API), chrysin (CRI) and beta-carotene (BTC) have shown potential for UV-VIS protection. This paper reports a photosafety and efficacy screening of such antioxidants through evaluation of the photostability, photoreactivity and phototoxicity as well as UVA/UVB ratio and critical wavelength. The assessment of the photostability, photoreactivity and phototoxicity of API, CRI and BTC, isolated and combined (CMB) was performed by HPLC, ROS assay and 3T3 NRU phototoxicity test, respectively. The phototoxicity test was also performed for CMB plus bemotrizinol (BMZ). The in vitro evaluation of the UVA protection was assessed by the determination of the UVA/UVB ratio and the critical wavelength. The antioxidants API, CRI, BTC and CMB were stable under UVA/VIS and VIS light. However weak photoreactivity after UVA/VIS irradiation was observed for API, CRI and CMB in the ROS assay. In the 3T3 NRU phototoxicity test, phototoxic potential was observed for CRI, BTC, CMB and CMB+BMZ after UVA/VIS exposure, and for BTC and CMB after VIS exposure. BMZ reduced the phototoxic potential of CMB in the VIS range. In the in vitro evaluation of UVA protection API, CRI, BTC, CMB and CMB+BMZ presented ultra UVA protection (UVA/UVB ratio>0.9) and exhibited critical wavelength close to or above 370nm. In conclusion, the use of API, CRI, BTC and their CMB aiming skin photoprotection could be considered safer in the VIS range. Furthermore, API presented the best performance in the photosafety screening among the studied antioxidants, since it was photostable and non-phototoxic in UVA/VIS and photostable, non-photoreactive and non-phototoxic in VIS range.