UVB Rays Research Articles

Preparation of eco-friendly multifunctional lyocell fabric with flame retardant, antibacterial and UV resistant using glucose-derived NP compounds.

A biomass-based finishing agent (ArCP) rich in nitrogen and phosphorus was synthesized from glucose, arginine and phosphorous acid, which was then used for lyocell fabrics to prepare flame retardant, antibacterial and UV resistant properties lyocell fabrics (ArCP-lyocell). The elemental composition, surface morphology, combustion performance, antibacterial and UV resistant properties for the lyocell fabrics before and after modification were investigated. ArCP-lyocell fabrics showed excellent self-extinguishing properties with a limiting oxygen index (LOI) of 35.1% and maintained an LOI of 30.7% even after 30 laundering cycles (LCs). Antibacterial experiments confirmed the antibacterial effect of ArCP-lyocell against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with 99.9% and 92.8% inhibition rates, respectively. In addition, the modified fabrics exhibited excellent UV resistant properties with a UV production factor (UPF) of up to 184.54, and lower transmittance both UVA and UVB rays under 2%. This study provides a simple and efficient approach for developing eco-friendly multifunctional textiles.

Exploring the Role of Artificial Light and Tanning for Skin Cancer

Skin cancer is a complex health condition with a high mortality rate all over the world. The present review article examines the relationship between artificial light exposure, tanning practices, and skin cancer. Artificial light exposure and tanning practices have been linked to various health concerns, particularly skin cancer. Artificial light sources that initiate and progress skin cancers are blue light, laptops, smartphones, and personal computers, leading to significant impacts on the human body. Artificial light exposure and tanning practices have been linked to various health concerns, particularly skin cancer. Both artificial light sources, such as tanning beds) and natural sunlight emit UVA and UVB rays, which can damage DNA in skin cells, leading to mutations that can develop into skin cancer. Tanning beds, in particular, pose a significant risk due to their high levels of UVA radiation. In addition, skin cancer was induced only in the mice exposed to blue light. Long-term blue light irradiation also increased the migration of neutrophils and macrophages involved in carcinogenesis in the skin. The review article also summarized the mechanisms of action of these factors in the progression and development of skin cancer as well.

Exploring the Role of Artificial Light and Tanning for Skin Cancer

Skin cancer is a complex health condition with a high mortality rate all over the world. The present review article examines the relationship between artificial light exposure, tanning practices, and skin cancer. Artificial light exposure and tanning practices have been linked to various health concerns, particularly skin cancer. Artificial light sources that initiate and progress skin cancers are blue light, laptops, smartphones, and personal computers, leading to significant impacts on the human body. Artificial light exposure and tanning practices have been linked to various health concerns, particularly skin cancer. Both artificial light sources, such as tanning beds) and natural sunlight emit UVA and UVB rays, which can damage DNA in skin cells, leading to mutations that can develop into skin cancer. Tanning beds, in particular, pose a significant risk due to their high levels of UVA radiation. In addition, skin cancer was induced only in the mice exposed to blue light. Long-term blue light irradiation also increased the migration of neutrophils and macrophages involved in carcinogenesis in the skin. The review article also summarized the mechanisms of action of these factors in the progression and development of skin cancer as well.

CORRELATION OF SUN PROTECTION FACTOR OF SUNSCREEN WITH ABSORBANCE AND TRANSMITTANCE IN THE ULTRAVIOLET RANGE OF RADIATION

Introduction: Ultraviolet solar radiation (UV) is harmful to people both because of sunburn and because of much more serious health problems, among which skin cancer is one of the most serious consequences of exposure to UVA and UVB radiation. Sunscreens protect the skin from harmful solar radiation,by absorbing or blocking UV radiation. The aim of the paper is to determine the correlation between the sun protection factor (SPF) and the absorbance of UV radiation of a domestic brand of sunscreen, and to compare the effectiveness of the domestic brand of sunscreen with other commercially available brands. Method: The UV-Vis spectrophotometric method was used to determine the correlation of the sun protection factor (SPF) with the absorbance and transmittance of UVA and UVB radiation. Results: The results showed a very good correlation and linear dependence of SPF with absorbance in the UVA (R2= 0.993) and in the UVB area (R2= 0.998).A statistically significant difference (P < 0.0001) was observed in the absorbance of UVA and UVB radiation of different brands of sun protection creams with the same protection factor. Conclusion: This study shows a direct correlation between SPF sunscreen and absorbance, which assesses the effectiveness of sunscreens in blocking UVA and UVB radiation. However, it is important to point out that all the researched creams, although they block different amounts of UV radiation, all absorb both UVA and UVB rays. Keywords: Ultraviolet radiation, sun protection factor, absorbance, transmittance

Sunscreen Effect of Andaliman Methanol Extract Nano Gel on The Amount of Melanin in Wistar Rats Exposed to UV-B Light

Excessive exposure to UV-B rays can increase melanin production, potentially causing skin damage, making it necessary to prevent this through the use of natural-based sunscreens, such as nano gel from methanol extract of andaliman, to protect the skin from the harmful effects of UV-B radiation. This study aims to evaluate the sunscreen effect of andaliman methanol extract nanogel on the amount of melanin in Wistar rats exposed to UV-B light. The method used was a laboratory experimental study with a randomized posttest only with a control group design using mice as the research subjects. The results of the study showed that the SPF values of andaliman extract at concentrations of 2%, 3.5%, and 5% were 2.11, 2.49, and 2.45, respectively, which are considered low for sunscreen protection standards. Additionally, the amount of melanin obtained from each treatment group was also categorized as small, indicating that the andaliman extract in nano gel form did not significantly reduce melanin production in Wistar rats exposed to UV-B rays. In conclusion, there is no sunscreen effect of andaliman methanol extract nanogel on the amount of melanin in Wistar rats exposed to UV-B light. This could be due to factors such as the low SPF value, the lack of stability of the active ingredients in the nano gel, or the need for an increased dosage. The implications of these findings suggest the need for further research to optimize the formulation or explore other more effective ingredients in preventing melanin production caused by UV-B exposure.

Engineered environment-friendly multifunctional food packaging with superior nonleachability, polymer miscibility and antimicrobial activity

This study was conducted primarily to develop an environment-friendly food packaging boasting several advantages, including good water vapor barrier, UV resistance, antimicrobial activity, non-leachability, and polymer miscibility. Initially, the starch-based antimicrobial agent (OCSI) was synthesized through a simple esterification reaction between oxidized corn starch (OCS) and indoleacetic acid (IAA). Subsequently, OCSI was further blended separately with environmentally-friendly materials (PVA, PBAT, PCL), and a series of environment-friendly packaging films were successfully prepared. The resulting films exhibited desirable thermal stability and 100 % barrier against both UV-A and UV-B rays. Moreover, the films presented effective barriers against water vapor, antioxidant, and antimicrobial activity against E. coli and S. aureus. Meanwhile, the films could significantly inhibit the deterioration of fresh fruits and prolong shelf life, considerably expanding their utilization in safe packaging. The environment-friendly packaging not only realized the sustainable utilization of green polymers, but also offered novel insights into the exploration of sustainable packaging.

The Potential of Natural Compounds in UV Protection Products.

Overexposure to ultraviolet radiation mainly leads to skin disorders (erythema, burns, immunosuppression), skin aging, and skin cancer as the most serious side effect. It has been widely accepted that using sunscreen products is an important way to protect against the harmful effects of UV rays. Although commercial sunscreens have constantly changed and improved over time, there are emerging concerns about the safety of conventional, organic, UV filters due to adverse effects on humans (such as photoallergic dermatitis, contact sensitivity, endocrine-disrupting effects, etc.) as well as accumulation in the environment and aquatic organisms. This is why natural compounds are increasingly being investigated and used in cosmetic and pharmaceutical sunscreens. Some of these compounds are widely available, non-toxic, safer for use, and have considerable UV protective properties and less side effects. Plant-based compounds such as flavonoids can absorb UVA and UVB rays and possess antioxidant, anticarcinogenic, and anti-inflammatory effects that contribute to photoprotection. Apart from flavonoids, other natural products such as certain vegetable oils, carotenoids, stilbenes, and ferulic acid also have UV-absorbing properties. Some vitamins might also be beneficial for skin protection due to their antioxidant activity. Therefore, the aim of this research was to gain insight into the potential of natural compounds to replace or reduce the amount of conventional UV filters, based on recent research.

Effects of benzophenone-3 on the liver and thyroid of adult zebrafish

Benzophenone-3 (BP-3), commonly known as oxybenzone, is an organic compound that acts as a sunscreen, protecting the skin from UVA and UVB rays. Thus, the objective of this study was to investigate the effects of BP-3 on the liver and thyroid using morphological and biochemical approaches. Adult male zebrafish were randomly assigned to three groups, each with three repetitions (n = 10 per group) water control, solvent control (0.01% ethanol), and 1 μg/L of BP-3, using a static exposure system for 96 h. After the experiment, histopathological analyses of the liver and thyroid were performed, along with histochemical analyses (glycogen) and biochemical evaluations of the antioxidant enzymes superoxide dismutase (SOD) and Catalase (CAT). Exposure to BP-3 resulted in significant histopathological changes in the liver of Danio rerio, increasing the frequency of circulatory disturbances, progressive changes, inflammatory responses, and regressive changes. On the other hand, the thyroid gland did not show any morphological changes during exposure to BP-3, maintaining its typical structure with follicles. There was a significant increase in SOD activity, while CAT showed no changes after 96 h of exposure. The results obtained demonstrate that exposure to BP-3 causes significant morphophysiological changes in the liver of D. rerio, highlighting not only the negative impacts on the health of these organisms but also the ecotoxicological potential of the substance and its consequences for aquatic biota in contaminated environments.

Carboxymethyl chitosan oligosaccharide enzymatic hydroxylates with reactive oxygen species scavenging and anti-inflammatory activity for topical treatment of skin photodamage

Skin photodamage caused by ultraviolet (UV) radiation is a major public health concern. UVB rays penetrate the epidermis, inducing oxidative stress and compromising essential cellular components. The demand for natural ingredients with properties such as moisturization, anti-inflammatory effects, antioxidant protection, and compatibility is increasing to combat the impact of photodamage on the skin. Herein, the carboxymethyl chitosan oligosaccharide (CM-COS) enzymatic hydroxylates were used on the topical application of skin photodamage for the first time. CM-COS, the degradation product of carboxymethyl chitosan, has high water solubility and multiple biological activities. Results showed that CM-COS promoted human epidermal cell (HaCaT) migration without causing cytotoxicity. In photodamaged HaCaT cells, CM-COS maintained cell viability and cytoskeletal integrity while inhibiting reactive oxygen species accumulation, apoptosis, and cell cycle arrest. CM-COS regulates gene expression related to cell cycle, oxidative stress, and inflammation in UVB-radiated HaCaT based on transcriptomic and qPCR data. In UVB-exposed mice, topical treatment of CM-COS significantly alleviated redness and scab formation and increased the moisture content of photodamaged skin. Histological analyses revealed reduced epidermal thickness and increased collagen I and collagen III deposition in photodamaged skin following CM-COS treatment. Additionally, gene expression related to the cell cycle, extracellular matrix, and inflammation were significantly activated by CM-COS based on transcriptomic and qPCR data. CM-COS modulated the levels of collagen and inflammation-related proteins. Collectively, the data confirm the therapeutic effect of CM-COS against skin photodamage and highlight the potential of natural marine oligosaccharides for treating skin diseases such as aging, wounds, and burns.

New Formulations of Acyclothymidine Dinucleosides Reduce Damaging Effects of Ultraviolet Radiation in an Ex Vivo Skin Model.

The greatest risk factor for skin cancer is exposure to ultraviolet (UV) rays of the sun. Among the three types of solar radiation (UVA, UVB, UVC), UVB rays are most commonly associated with skin cancer. UVB exposure promotes the formation of cyclobutane pyrimidine dimers (CPDs) in the DNA of cells in the epidermal skin layers, which can lead to mutations as DNA repair machinery attempts to repair the damage. These mutations can lead directly to skin carcinogenesis. Previous studies in animal and in human ex vivo skin models have shown that topical application of acyclothymidine dinucleosides protects DNA from UV-induced damage by preventing the formation of CPDs and helps initiate repair through the activation of DNA repair enzymes. Here we review the biological evidence leading to the development and formulation of ProteXidineTM (Topix Pharmaceuticals, Inc., Amityville, NY), as a UV protective agent for topical human application. We also provide clinical data pertaining to four ProteXidineTM formulations (test materials 1-4) tested for their abilities to reduce CPDs in an ex vivo human skin tissue model. J Drugs Dermatol. 2024;23(11):953-956. doi:10.36849/JDD.8420.

UV-B light (radiation) affects the metabolism of pigments and fatty acids in green algae Edaphochlorella mirabilis and Klebsormidium flaccidum in vitro

Algae offer a rich source of bioactive compounds suitable for food products and bioenergy. Environmental challenges such as nutrient scarcity, extreme pH and temperature, high light intensity, and UV radiation usually trigger algae to produce excess of lipids, antioxidants, and other bioprotective molecules as part of their adaptations for survival. Algal cultivation provides proteins, lipids, carbohydrates, vitamins, antioxidants, and trace elements. This study focused on understanding how UV-B irradiance, as an abiotic stressor, can influence the growth and metabolite production of two green algal species, Edaphochlorella mirabilis (Chlorophyta) and Klebsormidium flaccidum (Charophyta). Using a temporary immersion system bioreactor for in-vitro algal growth, the results showed no significant difference in biomass for both algal species after the exposure to UV-B rays. However, the assessment of malondialdehyde levels revealed a significantly higher tendency towards lipid peroxidation in treated E. mirabilis (+ 90 %) compared to control. Conversely, K. flaccidum did not display significant differences, thereby highlighting a more advanced adaptive capacity against UV-B radiation. Overall, both algal species treated with UV-B showed increased pigment accumulation. K. flaccidum exhibited an average pigment increase of over 53 %, while E. mirabilis showed a lower increase, over 30 % on average. The notable rise in antioxidant compounds (lutein, β-carotene, and chlorophyll a) in UV-B exposed K. flaccidum samples also suggested a more suitable adaptive strategy to mitigate oxidative stress in Charophyta. In K. flaccidum, the increase in polyunsaturated fatty acids can be associated with increased production of antioxidant compounds. Conversely, E. mirabilis appeared to protect itself by decreasing polyunsaturated fatty acids in favor of saturated ones. In both algal species, the increase in secondary metabolites under UV stress highlighted potential as a novel food source for human consumption, deserving further investigation.

Exploring Preventive Measures and Disease Dynamics of Hereditary Polymorphic Light Eruption in American Indian Children

Hereditary polymorphic light eruption (HPLE) is a condition related to polymorphic light eruption (PLE). Unlike PLE, HPLE is unique to American Indian populations demonstrating autosomal dominant inheritance pattern with incomplete penetrance. Affected individuals possess hypersensitivity to long UV radiation, which heightens the risk for skin damage. Onset is typically childhood and disease severity results in complications including psychosocial trauma, streptococcal pyoderma, and glomerulonephritis. HPLE can be difficult to diagnose due to its overlapping qualities with other conditions, underscoring the importance of accurate diagnosis and management. Preventive measures play critical roles in mitigating disease occurrence and complications. Literature analysis of five articles using PubMed and Google was conducted to understand HPLE among the Native American community, particularly children. Search terms included hereditary polymorphic light eruption, Native Americans, American Indians, polymorphic light eruption, actinic prurigo, UV toxicity, and photosensitivity. Literature delineated the disease process of HPLE and preventive measures. Studies revealed a higher incidence among children/adolescents who presented with rashes within two hours of sun exposure. Rash severity increased as seasons progressed to summertime. It is imperative that affected individuals utilize broad spectrum coverage sunscreen, covering UVA and UVB rays. Other measures proven to be effective include protective clothing, limiting time outdoors during peak sun hours, and using specially formulated lip balm. HPLE creates a unique challenge among American Indian populations necessitating increased awareness and educational strategies to minimize and avoid complications. Providing education on prevention and actively implementing measures can help decrease the complications of HPLE and increase quality of life.

Multi-Omics Analysis Reveals the Molecular Mechanisms of the Glycolysis and TCA Cycle Pathways in Rhododendron chrysanthum Pall. under UV-B Stress

UV-B radiation is becoming a bigger threat to plants as a result of the ozone layer’s depletion. As an alpine plant, Rhododendron chrysanthum Pall. (R. chrysanthum) may grow regularly under UV-B radiation throughout its lengthy acclimatization period, although the mechanism of acclimatization is still poorly understood. The current investigation uncovered a number of adaptation strategies that R. chrysanthum has developed in reaction to UV-B rays. UV-B radiation impeded photosynthesis and damaged the photosystem, according to OJIP testing. Through transcriptomics and proteomics analyses, this study found that the differential proteins and differential genes of R. chrysanthum were significantly enriched in glycolysis and tricarboxylic acid (TCA) cycle pathways after UV-B treatment. The metabolomics results showed that a total of eight differential metabolites were detected in the glycolytic and TCA cycle pathways, and the changes in the expression of these metabolites reflected the final outcome of gene regulation in the glycolytic and TCA cycle pathways. The combined experimental results demonstrated that R. chrysanthum’s photosynthetic system was impacted by UV-B stress and, concurrently, the plant activated an adaptation mechanism in response to the stress. To maintain its energy supply for growth, R. chrysanthum adapts to UV-B stress by adjusting the expression of the relevant proteins, genes, and metabolites in the glycolytic and TCA cycling pathways. This study provides a new perspective for understanding the changes in the carbon metabolism of R. chrysanthum under UV-B stress and its mechanisms for UV-B resistance, and provides an important theoretical basis for the study of enhancing plant resistance to stress.

1,3-Naphthoxazine derivatives: Synthesis, in silico pharmacokinetic studies, antioxidant and photoprotective properties

Investigation into the interactions between photoprotective agents and skin can offer a precise understanding of their biological behaviors in vitro and in vivo, providing crucial insights for generating new substances. For this purpose, we designed and synthesized a series of naphthoxazine derivatives and examined their photoprotective properties. 1,3-naphthoxazine derivatives were synthesized through the multi-component reaction of 2-naphthol, arylamines and aromatic aldehydes in the presence of copper(II) trifluoromethanesulfonate (Cu(OTf)2) and (±)-Camphor-10-sulfonic acid ((±)-CSA) catalyst system under sonication. The potential of these synthesized 1,3-naphthoxazine derivatives as antioxidants and viable organic structural-based sunscreen ingredients has been investigated. Sun protection factor (SPF) assay results showed that especially compounds 4i, 4c, 4k, 4d, 4r, and 4h had remarkably high activity (23.65, 23.57, 23.04, 21.94, 20.80, and 20.26, respectively at 900 µg/mL concentration). Additionally, antioxidant activity of the synthesized compounds was evaluated and compounds 4h, 4e, 4b, and 4j exhibited the highest activities in DPPH scavenging activity assay (86.46 %, 82.83 %, 80.78 %, and 80.65 % respectively at 400 µg/mL concentration). The synthesized compounds exhibit promising characteristics for effective UV radiation absorption, suggesting their suitability for inclusion in sunscreen formulations. Cytotoxic activity of compound 4k against normal human fibroblast cell line (MRC-5) was determined by CVDK-8 method. The results revealed that the compound provided remarkable viability (87.55 %) of MRC-5 cells at concentration of 100 µM. The study explores their efficacy in providing broad-spectrum protection against UVA and UVB rays, degradation and photostability, ADMET profile, and other pharmacokinetic properties.

KGF-2 ameliorates UVB-triggered skin photodamage in mice by attenuating DNA damage and inflammatory response and mitochondrial dysfunction.

Long-term exposure to UVB induces DNA damage, inflammatory response, mitochondrial dysfunction, and apoptosis in skin cells, thus causing skin photodamage. Research has demonstrated the noteworthy antioxidant, anti-inflammatory, DNA repair, and mitochondrial protective properties of keratinocyte growth factor-2 (KGF-2). To examine the impact of KGF-2 on UVB-triggered skin photodamage in mice, hair-removed mice were initially exposed under UVB radiation and subsequently treated with KGF-2 hydrogel and repeated for 6 days. On day 7, the assessment of histopathological alterations, inflammation, DNA damage, mitochondrial function, and apoptosis in mouse skin was assessed. It was found that KGF-2 could effectively relieve cutaneous photodamage symptoms and inhibit epidermal proliferation in mice. Meanwhile, KGF-2 was found to significantly reduce DNA damage, attenuate the inflammatory response, and inhibit the mitochondria-mediated intrinsic apoptotic pathway in the UVB-exposed mouse skin photodamage model. To summarize, our results indicated that KGF-2 reduces the severity of mouse skin photodamage caused by UVB rays by attenuating DNA damage and the inflammatory response, besides inhibiting the mitochondria-mediated intrinsic apoptosis pathway.

Overview of proficiency testing results for the invivo determination of sun protection factor.

A sunscreen product is allowed to be marketed if a protection is provided against ultraviolets (UV) including UVA rays and UVB rays expressed by the sun protection factor (SPF). UVB is radiation that is in the region of the ultraviolet spectrum which extends from about 290 to 320 nm in wavelength and that is primarily responsible for sunburn, ageing of the skin, and the development of skin cancer. Thus, since April 2009, the Bureau Interprofessionnel d'Etudes Analytiques (BIPEA) set up a proficiency testing scheme (PTS) for the determination of SPF invivo of sunscreen products according to ISO 24444 standard [Cosmetics - Sun protection test methods - in vivo determination of the sun protection factor (SPF)] to evaluate the analytical performances of laboratories on these analyses. This PTS gathers twenty-six laboratories around the world with one trial a year. For each test, the statistical treatment of the data is performed according to ISO 13528 standard [Statistical methods for use in proficiency testing by interlaboratory comparison]. The assigned and tolerance values are calculated from the participants' data and the performances of the laboratories are evaluated individually and collectively according to ISO 17043 standard [Conformity assessment - General requirements for proficiency testing]. This paper presents the design of the PT program, its development, and an attentive analysis of laboratories results, which highlight the global performances obtained by laboratories on this type of analysis. The evaluation of the results shows, in fact, a relatively constant dispersion of data since the implementation of the PT program (variability between 10% and 50%).

Formulation and SPF Value Evaluation of Sunscreen Spray Gel Containing Lime Peel Extract (Citrus aurantifolia)

Background: High exposure to sunlight has adverse effects on the skin. Lime peel contains more than 60% flavonoids, presenting the potential to function as a sunscreen due to the presence of conjugated aromatic benzene groups, capable of absorbing UV-A or UV-B rays from the sun. To prevent skin damage, lime peel extract is formulated into a spray gel, as it has the ability to dry rapidly, enhancing overall comfort for consumers during application. Objective: To determine the influence of variation concentration of lime peel extract in the sunscreen spray gel on its physical properties and in vitro SPF value. Methods: Lime peel crude extract was obtained using 70% ethanol and formulated into a sunscreen spray gel at concentrations of 5%, 10%, and 15%. The spray gel formulation was evaluated for its physical quality and SPF value. Results: The variation in extract concentration has a statistically significant effect on the physical properties of the preparation and SPF values (P<0.05). The physical stability conditions in each formula (F1, F2, and F3) meet the requirements of the spray gel preparation in terms of pH, viscosity, spreading test, drying time test, and adhesion test. The spray gel preparations F1 (5%), F2 (10%), F3 (15%) each have SPF values of 20, 25, and 35 respectively. Conclusion: The spray gel formulations in F1 (5%), F2 (10%), and F3 (15%) are physically stable and have moderate to high SPF values, with F3 (15%) having the highest SPF value of 35.

Effect of Petai Bark Extract Gel on Tyrosinase and TRP1 Gene Expression (In Vivo Experimental Study on Hyperpigmented Wistar Mice Exposed to UVB Model)

UVB irradiation can induce the formation of Reactive Oxygen Species (ROS) which causes activation of melanin synthesis through activation of tyrosinase and tyrosinase related protein-1 (TRP1). Secondary metabolites contained in petai peel extract are known to play a role in inhibiting ROS production due to exposure to UVB rays. This study aims to determine the effect of administering petai peel extract gel on the expression of the tyrosinase and TRp1 genes in mouse skin tissue exposed to UVB. The research design was posttest only control group with a completely randomized design method. The samples studied were 24 mice exposed to UVB light with a wavelength of 302 nm and an energy of 390mJ/cm2/day 3 times a week for 2 weeks. This research was carried out in four groups, namely the healthy group (K1), the negative control group (K2), treatment 1 (K3) with 10% petai peel extract gel and treatment 2 (K4) with 20% petai peel extract gel. Tyrosinase and TRP1 gene expression was analyzed using qRT-PCR. qRT-PCR analysis showed that there was a significant decrease in tyrosinase and TRP1 gene expression between groups K3 (tyrosinase 3,19±2,12 and TRP1 4,96±3,42) and K4 (tyrosinase 0,65±0,44 and TRP1 2,22±1,18) compared to group K2 (tyrosinase 17,92±3,77 and TRP1 35,91±4,52). Administration of petai peel extract gel can reduce the expression of tyrosinase and TRP1 genes in hyperpigmentation mice exposed to UVB light.

Sunlight exposure on human health and vitality

This paper studies the influence of sunlight on various aspects of human life, primarily on the skin. It destroys its components, such as collagen and melanin, and leads to various diseases, including skin cancer. It analyses the peculiarities of the sun's effect on the human body, its performance and the consequences of constant or one-time exposure. The work details the risks of sunlight exposure, including an increased risk of skin cancer, pigment spots, blisters, premature ageing, chronic inflammation, burns, as well as the exposure of high temperatures on humans, causing heat stroke and dehydration. It also characterizes two types of UV rays that can penetrate the skin – UVA and UVB rays – and emphasizes the danger of tanning, which is the protective reaction of our skin, and the consequences of which are various negative effects on the skin. The main part of the paper makes clear recommendations on how to prevent sun rays on the skin to ensure safe human activity. In conclusion, the important role of sunlight for our planet and the harm to human health, which can be prevented by observing the rules under

Retinoids—A unique ingredient for skin rejuvenation employing novel drug delivery systems

Millions of people around the world fall within the age group of 35 and above; having fluctuating lifestyles, increased exposure to blue light, and a faster-depleting ozone layer that enhances entry of UVA and UVB rays in the skin which tends to age faster leading into collagen degradation that results in fine lines and decreased cell senescence. The goal of skin rejuvenation is to have healthy skin. Cosmeceuticals incorporating retinoids have been increasingly used over the past few years to promote collagen synthesis and rejuvenate the skin. Photo-induced and chronological aging processes are decelerated with retinoid application that endorses skin elasticity by free radical neutralization, new cell growth, and blood vessel promotion within the skin to help fight pigmentation and reduce fine lines. Retinoids are commercially available as creams and serums for topical application. Nanotechnology is used in the development of retinoids to counteract adverse reactions like skin irritation and purging to improve its stability, efficacy, and acceptability. Emerging studies on retinoids include formulating them within liposomes, solid lipid nanoparticles, nano-emulgels, and hydrogels. This review details understanding the aging process, the mechanism of action of retinoids to counterfeit aging, and the potential use of nanotechnological delivery in cosmeceuticals.