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Microalgae are photosynthetic organisms known for producing valuable metabolites under different conditions such as extreme temperatures, high salinity, osmotic pressure, and ultraviolet radiation. In recent years, these metabolites have become a trend due to their versatility in applications such as pharmaceuticals, cosmetics, and others. They have even been proposed as an alternative source of bioactive metabolites to avoid the harmful effects on the environment produced by active compounds such as oxybenzone in commercials sunscreens. One of the most studied applications is the use of microalgae for skin care and topical use as cosmeceuticals. With the increasing demand for more environmentally friendly products in cosmetics, microalgae have been further explored in relation to this application. It has been shown that some microalgae are resistant to UV rays due to certain compounds such as mycosporine-like amino acids, sporopollenin, scytonemin, and others. These compounds have different mechanisms of action to mitigate UV damage induced. Still, they all have been proven to confer UV tolerance to microalgae with an absorbance spectrum like the one in conventional sunscreens. This review focuses on the use of these microalgae compounds obtained by UV stimulation and takes advantage of their natural UV-resistant characteristics to potentially apply them as an alternative for UV protection products.

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Mycosporines and mycosporine-like amino acids are ultra-violet-absorbing compounds produced by several organisms such as lichens, fungi, algae and cyanobacteria, especially upon exposure to solar ultraviolet radiation. These compounds have photoprotective and antioxidant functions. Mycosporine-like amino acids have been used as a natural bioactive ingredient in cosmetic products. Several reviews have already been developed on these photoprotective compounds, but they focus on specific features. Herein, an extremely complete database on mycosporines and mycosporine-like amino acids, covering the whole class of these natural sunscreen compounds known to date, is presented. Currently, this database has 74 compounds and provides information about the chemistry, absorption maxima, protonated mass, fragments and molecular structure of these UV-absorbing compounds as well as their presence in organisms. This platform completes the previous reviews and is available online for free and in the public domain. This database is a useful tool for natural product data mining, dereplication studies, research working in the field of UV-absorbing compounds mycosporines and being integrated in mass spectrometry library software.

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Ultraviolet radiation (UVR) has detrimental effects on human health. It induces oxidative stress, deregulates signaling mechanisms, and produces DNA mutations, factors that ultimately can lead to the development of skin cancer. Therefore, reducing exposure to UVR is of major importance. Among available measures to diminish exposure is the use of sunscreens. However, recent studies indicate that several of the currently used filters have adverse effects on marine ecosystems and human health. This situation leads to the search for new photoprotective compounds that, apart from offering protection, are environmentally friendly. The answer may lie in the same marine ecosystems since molecules such as mycosporine-like amino acids (MAAs) and scytonemin can serve as the defense system of some marine organisms against UVR. This review will discuss the harmful effects of UVR and the mechanisms that microalgae have developed to cope with it. Then it will focus on the biological distribution, characteristics, extraction, and purification methods of MAAs and scytonemin molecules to finally assess its potential as new filters for sunscreen formulation.

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Since the beginning of life on Earth, cyanobacteria have been exposed to natural ultraviolet-A radiation (UV-A, 315-400 nm) and ultraviolet-B radiation (UV-B, 280-315 nm), affecting their cells' biomolecules. These photoautotrophic organisms have needed to evolve to survive and thus, have developed different mechanisms against ultraviolet radiation. These mechanisms include UVR avoidance, DNA repair, and cell protection by producing photoprotective compounds like Scytonemin, carotenoids, and Mycosporine-like amino acids (MAAs). Lyngbya marine species are commercially important due to their secondary metabolites that show a range of biological activities including antibacterial, insecticidal, anticancer, antifungal, and enzyme inhibitor. The main topic in this review covers the Lyngbya sp., a cyanobacteria genus that presents photoprotection provided by the UV-absorbing/screening compounds such as MAAs and Scytonemin. These compounds have considerable potentialities to be used in the cosmeceutical, pharmaceutical, biotechnological and biomedical sectors and other related manufacturing industries with an additional value of environment friendly in nature. Scytonemin has UV protectant, anti-inflammatory, anti-proliferative, and antioxidant activity. MAAs act as sunscreens, provide additional protection as antioxidants, can be used as UV protectors, activators of cell proliferation, skin-care products, and even as photo-stabilizing additives in paints, plastics, and varnishes. The five MAAs identified so far in Lyngbya sp. are Asterina-330, M-312, Palythine, Porphyra-334, and Shinorine are capable of dissipating absorbed radiation as harmless heat without producing reactive oxygen species.

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Mycosporine-like amino acids (MAA) are ultraviolet screen substances synthesized by marine algae. The physiological function of these substances is related to cellular protection against UV radiation and as a protective mechanism against oxidative stress. These substances can be found mainly in the ocean, among red seaweeds. Its concentration in organisms has been related to ultraviolet radiation and availability of inorganic nitrogen in the environment. We start our study of MAA content in different species to understand if environmental conditions influence the concentration of MAAs in red seaweeds. The Brazilian coast presents abiotic factors that interact to create different physical-chemical features in the environment. We collected 441 samples from 39 species of red seaweed easily found in the intertidal zone, in low tide, during the summer of 2015. The sampling encompassed a latitudinal gradient (3° S to 28°5' S) at 23 points along the coast. We quantified and identified the content of MAAs in species through the method of high performance liquid chromatography. We detected for the first time the occurrence of MAAs in certain species of red algae that have not been reported to contain MAAs before. We confirmed that some environmental factors influenced the content of MAAs. Enhanced MAA contents, for example, were found in environments with a basic pH, a high ultraviolet index, and high concentrations of phosphate and nitrate. Salinity, dissolved oxygen and variations of sea surface temperature also influenced, in a secondary way, MAA content in algae in their natural environments.

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Mindfulness is a skill that allows the practitioner to expand an existing space between stimulus and response, so he/she may make more conscious choices which in turn prevents the perpetuation of dysfunctional patterns of behaviors, contributing to the improvement of his/her well-being. The goal of this study was to evaluate the psychometric properties of the Brazilian version of the Mindful Attention Awareness Scale (MAAS) in a sample with 395 participants divided into smokers, people from the general population, college students and meditators. They answered the MAAS and the Psychological Well-Being Scale (PWBS). An exploratory factor analysis was conducted to test the factor structure of the MAAS. Internal consistency, test-retest reliability and split half were respectively assessed with Cronbach's α and correlation coefficients. Construct validity was examined by correlating the MAAS with psychological well-being. Criterion validity was assessed by comparing the meditators' scores on the MAAS with the scores of other participants. After the exploratory factor analysis, the Brazilian MAAS remained a unidimensional scale. Reliability [α = .83; split half = .67 and test-retest = .80 (p < .001)] and validity measures were adequate, except the criterion validity which was not confirmed in the mentioned sample.

Mindfulness é uma habilidade que permite ao praticante a ampliação de um espaço existente entre um estímulo e a resposta, podendo o mesmo fazer escolhas mais conscientes e impedindo a perpetuação de padrões de comportamentos disfuncionais, contribuindo para a melhora de seu bem estar. Este estudo objetivou avaliar as propriedades psicométricas da versão brasileira da Mindful Attention Awareness Scale (MAAS). Participaram deste estudo 395 pessoas, divididos entre fumantes, comunidade geral, universitários e meditadores. Foi realizada análise fatorial exploratória para testar a estrutura fatorial da MAAS. A consistência interna foi testada através do alfa de Cronbach, além do teste-reteste e do método das metades, avaliados através de correlação. A validade de construto foi avaliada através da correlação entre a Escala de Bem Estar Subjetivo (EBES) e a MAAS. A validade de critério foi avaliada através da comparação dos escores dos meditadores e dos demais participantes na MAAS. Após a análise fatorial exploratória, a MAAS manteve-se uma escala unidimensional. As medidas de confiabilidade [α = 0,83; split half = 0,67 e teste reteste = 0,80 (p < 0,001)] e validade foram satisfatórias, exceto a validade de critério, não confirmada nesta amostra.

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Mindfulness is a skill that allows the practitioner to expand an existing space between stimulus and response, so he/she may make more conscious choices which in turn prevents the perpetuation of dysfunctional patterns of behaviors, contributing to the improvement of his/her well-being. The goal of this study was to evaluate the psychometric properties of the Brazilian version of the Mindful Attention Awareness Scale (MAAS) in a sample with 395 participants divided into smokers, people from the general population, college students and meditators. They answered the MAAS and the Psychological Well-Being Scale (PWBS). An exploratory factor analysis was conducted to test the factor structure of the MAAS. Internal consistency, test-retest reliability and split half were respectively assessed with Cronbach's α and correlation coefficients. Construct validity was examined by correlating the MAAS with psychological well-being. Criterion validity was assessed by comparing the meditators' scores on the MAAS with the scores of other participants. After the exploratory factor analysis, the Brazilian MAAS remained a unidimensional scale. Reliability [α = .83; split half = .67 and test-retest = .80 (p < .001)] and validity measures were adequate, except the criterion validity which was not confirmed in the mentioned sample.(AU)

Mindfulness é uma habilidade que permite ao praticante a ampliação de um espaço existente entre um estímulo e a resposta, podendo o mesmo fazer escolhas mais conscientes e impedindo a perpetuação de padrões de comportamentos disfuncionais, contribuindo para a melhora de seu bem estar. Este estudo objetivou avaliar as propriedades psicométricas da versão brasileira da Mindful Attention Awareness Scale (MAAS). Participaram deste estudo 395 pessoas, divididos entre fumantes, comunidade geral, universitários e meditadores. Foi realizada análise fatorial exploratória para testar a estrutura fatorial da MAAS. A consistência interna foi testada através do alfa de Cronbach, além do teste-reteste e do método das metades, avaliados através de correlação. A validade de construto foi avaliada através da correlação entre a Escala de Bem Estar Subjetivo (EBES) e a MAAS. A validade de critério foi avaliada através da comparação dos escores dos meditadores e dos demais participantes na MAAS. Após a análise fatorial exploratória, a MAAS manteve-se uma escala unidimensional. As medidas de confiabilidade [α = 0,83; split half = 0,67 e teste reteste = 0,80 (p < 0,001)] e validade foram satisfatórias, exceto a validade de critério, não confirmada nesta amostra.(AU)

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This study presents a translation of the Mindful Attention Awareness Scale (MAAS) into Mexican Spanish, and examines its psychometric properties as well as its relationship with socio-demographic variables. The MAAS measures the frequency with which people experience mindful states. A sample of N = 622 healthy adult Mexicans completed the MAAS. A smaller sub-sample (n=195) completed the Five-Facet Mindfulness Questionnaire (FFMQ), a well-known mindfulness measure, to obtain concurrent validity. Exploratory factor analysis (EFA) revealed a one-factor solution, and reliability coefficients were adequate. Confirmatory factor analysis (CFA) showed adequate goodness of fit indexes. Moreover, relationships between Mexican Spanish MAAS scores and socio-demographic variables were also explored, and differences between-groups were found in mean scores both in alcohol consumers and religious practitioners. No other significant differences between groups were found. Results suggest that the Mexican version of the MAAS is a reliable and valid instrument to use with a healthy adult Mexican sample.

Este estudio presenta una traducción de la Mindful Attention Awareness Scale (Escala de Atención Plena) al español mexicano y examina sus propiedades psicométricas, así como su relación con variables sociodemográficas. La Escala de Atención Plena mide la frecuencia con la que las personas experimentan estados de atención plena. Una muestra de N=622 adultos mexicanos sanos completaron la Escala de Atención Plena. Una submuestra más pequeña (n=195) completó el Cuestionario de Cinco Facetas de la Atención Plena, el cual es una escala bien conocida de atención plena, para obtener validez concurrente. El análisis factorial exploratorio reveló una solución unifactorial y los coeficientes de confiabilidad fueron adecuados. El análisis factorial confirmatorio mostró índices adecuados de bondad de ajuste. Además, también se exploraron las relaciones entre la versión Mexicana del MAAS y variables sociodemográficas, encontrándose diferencias entre grupos tanto en consumidores de alcohol como en practicantes de religión. No se encontraron otras diferencias significativas entre grupos. Los resultados sugieren que la versión mexicana de la MAAS es un instrumento confiable y válido para utilizarse con población mexicana adulta y sana.

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Autologous dendritic cells (DCs) loaded with tumor-associated antigens (TAAs) are a promising immunological tool for cancer therapy. These stimulate the antitumor response and immunological memory generation. Nevertheless, many patients remain refractory to DC approaches. Antigen (Ag) delivery to DCs is relevant to vaccine success, and antigen peptides, tumor-associated proteins, tumor cells, autologous tumor lysates, and tumor-derived mRNA have been tested as Ag sources. Recently, DCs loaded with allogeneic tumor cell lysates were used to induce a potent immunological response. This strategy provides a reproducible pool of almost all potential Ags suitable for patient use, independent of MHC haplotypes or autologous tumor tissue availability. However, optimizing autologous tumor cell lysate preparation is crucial to enhancing efficacy. This review considers the role of cancer cell-derived lysates as a relevant source of antigens and as an activating factor for ex vivo therapeutic DCs capable of responding to neoplastic cells. These promising therapies are associated with the prolonged survival of advanced cancer patients.

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Qualitative and quantitative studies of mycosporine-like amino acids (MAAs) in three species of the genus Gracilaria Greville (G. birdiae, G. domingensis and G. tenuistipitata) were performed. A simple and efficient extraction procedure based on ethanol was described. HPLC, UV and mass spectrometry experiments revealed different profiles between extracts obtained from one species cultivated in the laboratory (G. tenuistipitata) and two species collected in their natural environment (G. birdiae and G. domingensis). The levels detected in the latter two species were approximately 150 times higher than in the species cultivated in vitro. This study revealed that G. birdiae and G. domingensis present a potential source for economical exploration of MAAs.

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Coral reefs are impacted by a range of environmental variables that affect their growth and survival, the main factors being the high irradiance and temperature fluctuations. Specimens of Pocillopora capitata Verrill 1864 were exposed to photosynthetically active radiation (PAR) and ultraviolet radiation (UVR) for 32h under laboratory conditions. We examined lipid peroxidation (MDA), antioxidant enzyme activities (SOD, CAT, GPx and GST), chlorophyll a (Chl a), carotenoid pigments (CPs), mycosporine-like amino acids (MAAs), and expulsion of zooxanthellae. Our results revealed that corals exposed to UVR had relatively low levels of carotenoids and antioxidant enzyme activities compared to those exposed to PAR, as well as lower CPs/Chl a ratios. Although MAAs and CPs are rapidly produced as non-enzymatic antioxidants in response to UVR in corals, these were not sufficient, even in the dark phase of the experiment, to mitigate the damage caused by formation of reactive oxygen species (ROS), which caused breakdown of the symbiotic relationship between the zooxanthellae and the host animal to an extent 33 times greater than in the PAR treatment. In this study, it could be possible to distinguish that, parallel to the short-term adjustments, such as the amount of pigment in the algae or the sensitivity of the photosynthetic response reported in other species of coral, P. capitata exhibits at the enzymatic level a series of responses oriented to resist the effects derived from the propagation of ROS and, thus, to adapt to and maintain its reproductive capacity in shallow oceanic environments that commonly exhibit high UVR levels. Nevertheless, as a result of the inappropriate location of the artificial intercommunication structure of the Juluapan Lagoon with respect to the arrecifal area of study and therefore of the tides influence, other variables, such as the changes in short-term in turbidity, sediment inputs, nutrients, temperature and osmolarity, can act in combination and cause irreversible damage. The implementation of a management plan for the coralline reefs of the Mexican Pacific coast is required. Rev. Biol. Trop. 58 (1): 103-118. Epub 2010 March 01.

Los arrecifes de coral se ven afectados por una serie de variables ambientales que afectan su crecimiento y supervivencia, siendo los principales factores la alta irradiación y las fluctuaciones de temperatura. Los especímenes de Pocillopora capitata Verrill 1864 fueron expuestos a radiación activa fotosintéticamente (PAR) y radiación ultravioleta (RUV) por 32h en condiciones de laboratorio. Nosotros determinamos las concentraciones de peroxidación lipídica (MDA), actividades de enzimas antioxidantes (SOD, CAT, GPx y GST), clorofila a (Chl a), pigmentos carotenoides (CPS), aminoácidos tipo micosporina (MAAS), y la expulsión de las zooxantelas. Nuestros resultados muestran que los corales expuestos a los rayos UV presentaban niveles relativamente bajos de carotenoides y actividad de las enzimas antioxidantes en comparación con los expuestos al PAR, así como tasas de CPs/Chl a bajas. Aunque MAAs y CPs se producen rápidamente como antioxidantes no enzimáticos en respuesta a la radiación ultravioleta en los corales, éstos no fueron suficientes, incluso en la fase oscura del experimento, para mitigar los daños causados por la formación de especies reactivas de oxígeno (ROS), lo que provocó una ruptura en la relación simbiótica entre las zooxantelas y el coral con una relación 33 veces mayor que en el tratamiento de PAR. A nivel enzimático, P capitata presentó una serie de ajustes orientados a resistir los efectos derivados de la propagación de ROS y con ello favorecer su adaptación y capacidad reproductiva en ambientes oceánicos caracterizados por altos niveles de UVR.

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