Polyphenols from Mediterranean Plants: Biological Activities for Skin Photoprotection in Atopic Dermatitis, Psoriasis, and Chronic Urticaria

The gut-skin axis: a bi-directional, microbiota-driven relationship with therapeutic potential

This review explores the emerging term "gut-skin axis" (GSA), describing the bidirectional signaling that occurs between the skin and the gastrointestinal tract under both homeostatic and disease conditions. Central to GSA communication are the gut and skin microbiota, the microbial communities that colonize these barrier surfaces. By influencing diverse host pathways, including innate immune, vitamin D receptor, and Aryl hydrocarbon receptor signaling, a balanced microbiota contributes to both tissue homeostasis and host defense. In contrast, microbiota imbalance, or dysbiosis at one site, can lead to local barrier dysfunction, resulting in the activation of signaling pathways that can disrupt tissue homeostasis at the other site, potentially leading to inflammatory skin conditions such as atopic dermatitis and psoriasis, or gut diseases like Inflammatory Bowel Disease. To date, most research on the GSA has examined the impact of the gut microbiota and diet on skin health, but recent studies show that exposing the skin to ultraviolet B-light can beneficially modulate both the gut microbiome and intestinal health. Thus, despite the traditional focus of clinicians and researchers on these organ systems as distinct, the GSA offers new opportunities to better understand the pathogenesis of cutaneous and gastrointestinal diseases and promote health at both sites.

Diospyros lotus leaf extract and its main component, myricitrin, inhibit both histamine‑dependent and histamine‑independent itching

Pruritus is a distressing symptom associated with various dermatological, systemic and neurological conditions, markedly impairing quality of life. Pruritus arises through histamine-dependent and histamine-independent pathways, involving mediators such as histamine, gastrin-releasing peptide (GRP), interleukin-31 (IL-31) and STAT3 signaling. The present study aimed to investigate the antipruritic effects of Diospyros lotus leaf extract (DLE) and its major constituent, myricitrin (MC), on ICR mice using compound 48/80 (histamine-dependent) and chloroquine (histamine-independent) itch models. Serum levels of histamine and IL-31 were measured by ELISA, and mast cell infiltration was assessed via toluidine blue staining. Furthermore, the expression and activation of GRP receptor (GRPR), IL-31RA and STAT3 in the spinal cord were analyzed using western blotting and immunofluorescence staining. Notably, DLE and MC significantly reduced scratching behavior, serum histamine levels and mast cell infiltration in both models. Immunofluorescence staining and western blot analysis revealed that DLE and MC downregulated GRPR, IL-31 receptor A and phosphorylated STAT3 expression in the spinal cord, indicating modulation of central itch signaling. Additionally, DLE and MC suppressed IL-31 levels in serum and skin tissues. These findings indicated that DLE and MC may alleviate pruritus through multiple mechanisms, including mast cell stabilization, histamine reduction and modulation of central itch pathways. The broad-spectrum antipruritic activity of DLE and MC highlights their potential as natural therapeutic agents for diverse pruritic conditions, offering a safer alternative to synthetic antipruritic drugs. Further research is warranted to validate these findings in clinical settings and to elucidate the molecular mechanisms underlying their efficacy.

The Western Diet and Atopic Dermatitis: The Potential Role of Nutrients, Contaminants, and Additives in Dysbiosis and Epithelial Barrier Dysfunction

Atopic dermatitis (AD) is a chronic inflammatory skin disorder influenced by both genetic and environmental factors, collectively termed the exposome. Among these determinants, diet emerges as a pivotal component, with diverse nutrients, contaminants, and additives shaping immune responses, microbiota composition, and systemic inflammatory status. This literature review aimed to elucidate the interplay between dietary factors and skin dysbiosis in AD, providing insights into how these interactions may impact disease susceptibility and progression. A comprehensive search of PubMed and Scopus was conducted using relevant keywords and medical subject headings (MeSH). Studies published in English within the past 25 years were included, encompassing in vitro, in vivo, and ex vivo research, as well as reviews. Priority was given to frequently cited articles, reflecting significant contributions to current understanding. Findings suggest that dietary habits influence AD by modulating both gut and skin microbiota, immune pathways, and inflammatory processes. These insights underscore the importance of considering diet within a broader exposome framework, paving the way for targeted interventions to improve AD management. Further research is needed to clarify the mechanisms and optimize nutritional strategies, potentially informing preventive and therapeutic approaches for AD.

Polyphenol autoxidation and prooxidative activity induce protein oxidation and protein-polyphenol adduct formation in model systems

Polyphenols are well-known for their antioxidant properties, but their prooxidative activity remain less understood. This study quantitatively examined the formation of hydrogen peroxide (H2O2) during the autooxidation of nine different polyphenols in model systems, investigating how it impacts protein oxidation and protein-polyphenol covalent adduct formation. Polyphenols (4 mM) generated H2O2 in the range of 0.2-242 μM, depending on type of polyphenol, incubation time, temperature, and pH, but no clear relationship between polyphenol structure and H2O2 production was observed. The presence of free amino acids and proteins (bovine serum albumin and β-lactoglobulin) inhibited H2O2 formation, with Cys completely scavenging H2O2. Met was highly susceptible to oxidation with a 25-75% loss, forming methionine sulfoxide through a two-electron oxidation pathway. Trp and Tyr were oxidized to produce dioxindolyl-ʟ-alanine, kynurenine, 3,4-dihydroxyphenylalanine, N'-formylkynurenine, and 5-hydroxytryptophan in the nmol/mol-mmol/mol amino acid range. Furthermore, autoxidation of polyphenols resulted in >177 distinct amino acid/protein-polyphenol adducts as identified using LC-Orbitrap-MS/MS analysis.

The Interactive Effects of Fruit Intake Frequency and Serum miR-484 Levels as Biomarkers for Incident Type 2 Diabetes in a Prospective Cohort of the Spanish Adult Population: The Di@bet.es Study

Background/Objectives: Although evidence suggests that miR-484 and several fruit components are involved in glucose metabolism and insulin resistance metabolic pathways, the relationship between serum miR-484 levels and fruit consumption in relation to the risk of Type 2 diabetes (T2DM) remains elusive. The aim of this study was to evaluate the possible association between serum miR-484 levels and fruit intake frequency with the risk of T2DM in the Spanish adult population. Methods: 2234 subjects from the Di@bet.es cohort study without T2DM at baseline were studied. Socio-demographic, anthropometric and clinical data were recorded, as well as responses to a questionnaire on habits, including frequency of fruit consumption (daily vs. occasional). T2DM was diagnosed at baseline and after 7.5 years of follow-up. Baseline serum miR-484 levels were measured using real-time qPCR and categorized based on the 25th percentile. Association analyses were performed using logistic regression models adjusted for potential confounders. Interaction effects were evaluated on the multiplicative and additive scales. Results: There was no association between miR-484 levels and fruit intake frequency. Categorized miR-484 levels and fruit consumption were inversely and independently associated with the likelihood of incident T2DM. Analysis of the interaction effect suggests the presence of both positive multiplicative and additive interactions between miR-484 categories and fruit consumption frequency. Conclusions: Our study demonstrates a protective effect of daily fruit intake and high miR-484 levels regarding the risk of T2DM and supports the nutritional recommendations advocating daily fruit consumption. This study also suggests that the combined effect of low miR-484 levels and occasional fruit intake may increase the risk of T2DM beyond their independent effects.

Detection of polyphenols in carob pods (Ceratonia siliqua) from Southern Italy by a LC-HRMS method

The presence of polyphenols was examined in carob pods (Ceratonia siliqua) from Southern Italy 90 days after harvest by the validation of a reliable LC-HRMS method. A greater abundance of Apigenin (51490.22 ± 34399.16 μg/Kg) and Myricetin (24897.92 ± 108332.05 μg/Kg) compared to previous research works conducted in Mediterranean countries. Significant differences in the polyphenol content between sampling areas (p < 0.05) were observed, particularly differences in hesperidin and myricetin. These differences confirmed the role of geochemical and climatic conditions in the variation of polyphenol content. This study is a first regarding the phenolic content of carob pods from Southern Italy, confirming the presence of these substances even long after harvest and that carob pods are valuable sources of phenolic substances that may be useful in the prevention of diseases related to oxidative stress.

Unraveling diabetes complexity through natural products, miRNAs modulation, and future paradigms in precision medicine and global health

BACKGROUND AND AIMS

The challenge posed by diabetes necessitates a paradigm shift from conventional diagnostic approaches focusing on glucose and lipid levels to the transformative realm of precision medicine. This approach, leveraging advancements in genomics and proteomics, acknowledges the individualistic genetic variations, dietary preferences, and environmental exposures in diabetes management. The study comprehensively analyzes the evolving diabetes landscape, emphasizing the pivotal role of genomics, proteomics, microRNAs (miRNAs), metabolomics, and bioinformatics.

RESULTS

Precision medicine revolutionizes diabetes research and treatment by diverging from traditional diagnostic methods, recognizing the heterogeneous nature of the condition. MiRNAs, crucial post-transcriptional gene regulators, emerge as promising therapeutic targets, influencing key facets such as insulin signaling and glucose homeostasis. Metabolomics, an integral component of omics sciences, contributes significantly to diabetes research, elucidating metabolic disruptions, and offering potential biomarkers for early diagnosis and personalized therapies. Bioinformatics unveils dynamic connections between natural substances, miRNAs, and cellular pathways, aiding in the exploration of the intricate molecular terrain in diabetes. The study underscores the imperative for experimental validation in natural product-based diabetes therapy, emphasizing the need for in vitro and in vivo studies leading to clinical trials for assessing effectiveness, safety, and tolerability in real-world applications. Global cooperation and ethical considerations play a pivotal role in addressing diabetes challenges worldwide, necessitating a multifaceted approach that integrates traditional knowledge, cultural competence, and environmental awareness.

CONCLUSIONS

The key components of diabetes treatment, including precision medicine, metabolomics, bioinformatics, and experimental validation, converge in future strategies, embodying a holistic paradigm for diabetes care anchored in cutting-edge research and global healthcare accessibility.

Plant Phenolics in the Prevention and Therapy of Acne: A Comprehensive Review

Plants are a rich source of secondary metabolites, among which phenolics are the most abundant. To date, over 8000 various polyphenolic compounds have been identified in plant species, among which phenolic acids, flavonoids, coumarins, stilbenes and lignans are the most important ones. Acne is one of the most commonly treated dermatological diseases, among which acne vulgaris and rosacea are the most frequently diagnosed. In the scientific literature, there is a lack of a detailed scientific presentation and discussion on the importance of plant phenolics in the treatment of the most common specific skin diseases, e.g., acne. Therefore, the aim of this review is to gather, present and discuss the current state of knowledge on the activity of various plant phenolics towards the prevention and treatment of acne, including in vitro, in vivo and human studies. It was revealed that because of their significant antibacterial, anti-inflammatory and antioxidant activities, phenolic compounds may be used in the treatment of various types of acne, individually as well as in combination with commonly used drugs like clindamycin and benzoyl peroxide. Among the various phenolics that have been tested, EGCG, quercetin and nobiletin seem to be the most promising ones; however, more studies, especially clinical trials, are needed to fully evaluate their efficacy in treating acne.

Bioactivity screening and molecular identification of Anchusa milleri L. sunflower crud extract for antioxidant, antiviral, antimicrobial, and anticancer properties

The current study evaluates hot water A. milleri sunflower extracts at 40 °C temperature (AMSE40) for their antibacterial, anti-biofilm, antiviral and anticancer activities. AMSE40 exhibited excellent antioxidant activity with an IC50 of 1.17 mg/mL (ascorbic acid) and was found to be rich in phytochemical compounds such as alkaloids, flavonoids, phenolics, saponins, and tannins, with concentrations of 1.23%, 351.60 mg/g, 152.50 mg/g, 0.98%, and 146.35 mg/g, respectively. AMSE40 showed strong antibacterial and anti-biofilm activity against four multidrug-resistant isolates, comprising E. faecalis, S. aureus, P. aeruginosa, and K. pneumonia with minimum bactericidal concentrations (25 mg/mL) and minimum inhibitory concentrations (12.5 mg/mL) for all isolates. The AMSE40 (62.5 µg/mL) showed antiviral efficacy against CoxB4 (9.1%) and HSV-1 (34.4%). Additionally, AMSE40 induced DNA fragmentation in liver cell lines, indicating cell death. The cytotoxic concentration of AMSE40 had a mild impact on Vero (283.2 µg) and HepG2 cells (76.4 µg). A. milleri has the potential to serve as a natural and eco-friendly source for innovative pharmaceutical and medical applications.

Nutraceutical and Medicinal Importance of Marine Molluscs

Marine molluscs are of enormous scientific interest due to their astonishing diversity in terms of their size, shape, habitat, behaviour, and ecological roles. The phylum Mollusca is the second most common animal phylum, with 100,000 to 200,000 species, and marine molluscs are among the most notable class of marine organisms. This work aimed to show the importance of marine molluscs as a potential source of nutraceuticals as well as natural medicinal drugs. In this review, the main classes of marine molluscs, their chemical ecology, and the different techniques used for the extraction of bioactive compounds have been presented. We pointed out their nutraceutical importance such as their proteins, peptides, polysaccharides, lipids, polyphenolic compounds pigments, marine enzymes, minerals, and vitamins. Their pharmacological activities include antimicrobial, anticancer, antioxidant, anti-inflammatory, and analgesic activities. Moreover, certain molluscs like abalones and mussels contain unique compounds with potential medicinal applications, ranging from wound healing to anti-cancer effects. Understanding the nutritional and therapeutic value of marine molluscs highlights their significance in both pharmaceutical and dietary realms, paving the way for further research and utilization in human health.

Molecular docking, MMGBSA, and ADMET studies of phytoconstituents of Ocimum gratissimum on multiple breast cancer targets

O. gratissimum is one of the most common medicinal plants in every community in Nigeria. This plant has been presumed to be useful in the management of diseases including breast cancer, which is one the commonest cancers affecting women globally. Hence, this study aimed to computationally investigate the phytochemicals present in O. gratissimum by elucidate their binding dynamics against five selected molecular targets of breast cancer and predict their pharmacokinetics properties. Molecular docking, MMGBSA calculation and ADMET prediction were used. The results showed that isovitexin has the highest binding affinity of -9.11 kcal/mol and -9.80 kcal/mol for Human Epidermal Growth Factor Receptor 2 (HER2) and Epidermal Growth Factor Receptor (EGFR) respectively. Rosmarinic acid has the highest binding affinity of -12.15 kcal/mol for Phosphatidylinositol 3-kinase (PI3K), Nepetoidin A has the highest binding affinity of -9.14 kcal/mol for oestrogen receptor (ER), and Vitexin has the highest binding affinity of -12.90 kcal/mol for Progesterone receptor (PR). MMGBSA provided total binding energy that confirmed the stability of the complexes under physiological conditions. The ADMET profiles showed that O. gratissimum top phytochemicals identified would be safe for oral administration with no hepatoxicity. Overall, this study identified isovitexin, vitexin, rosmarinic acid, nepetoidin A and luteolin among others, as compounds that exhibit strong anti-cancer properties against breast cancer cells.

Nutritional and Physiological Properties of Thymbra spicata: In Vitro Study Using Fecal Fermentation and Intestinal Integrity Models

(Poly)phenolic-rich Mediterranean plants such as Thymbra spicata have been associated with several health-promoting effects. The nutritional value, as well as physiological interaction of T. spicata with the gastrointestinal tract, has not been investigated before. The nutritional composition of T. spicata leaves was here characterized by standard analytical methods. T. spicata leaves were subjected to ethanolic extraction, simulated gastrointestinal digestion, and anaerobic microbial gut fermentation. Phenols/flavonoid contents and radical scavenging activity were assessed by colorimetric methods. The volatile organic compounds (VOCs) were detected by gas chromatography coupled with mass spectrometry. The effect on intestinal integrity was evaluated using a Caco-2 monolayers mounted in a Ussing chamber. T. spicata contains a high amount of fiber (12.3%) and unsaturated fatty acids (76% of total fat). A positive change in VOCs including short-chain fatty acids was observed without significant change in viable microbe. T. spicata and carvacrol (main phenolic compound) enhanced ionic currents in a concentration-dependent manner without compromising the Caco-2 monolayer's integrity. These effects were partially lost upon simulated digestion and completely abolished after colonic fermentation in line with polyphenols and carvacrol content. Conclusion: T. spicata represents a promising nutrient for the modulation of gut microbiota and the gut barrier. Further studies must better define its mechanisms of action.

The Promising Role of Polyphenols in Skin Disorders

The biochemical characteristics of polyphenols contribute to their numerous advantageous impacts on human health. The existing research suggests that plant phenolics, whether consumed orally or applied directly to the skin, can be beneficial in alleviating symptoms and avoiding the development of many skin disorders. Phenolic compounds, which are both harmless and naturally present, exhibit significant potential in terms of counteracting the effects of skin damage, aging, diseases, wounds, and burns. Moreover, polyphenols play a preventive role and possess the ability to delay the progression of several skin disorders, ranging from small and discomforting to severe and potentially life-threatening ones. This article provides a concise overview of recent research on the potential therapeutic application of polyphenols for skin conditions. It specifically highlights studies that have investigated clinical trials and the use of polyphenol-based nanoformulations for the treatment of different skin ailments.

Anti-Inflammatory Effect of Fermented Cabbage Extract Containing Nitric Oxide Metabolites with Silica

The aim of this study was to evaluate the anti-inflammatory effect of fermented cabbage extract (FC) containing nitric oxide metabolites with silica (FCS) on 1-fluoro-2,4-dinitrofluorobenzene (DNFB)-induced atopic dermatitis (AD) in BALB/c mice. Atopic dermatitis-like allergic contact dermatitis was induced by DNFB challenge in the ear after DNFB sensitization on the dorsal skin of mice. FCS alleviated the severity of atopic dermatitis-like skin lesions. In addition, epidermis thickness of the ear and penetration of inflammatory cells in atopic dermatitis-like skin lesions were decreased after topical application of FCS. The serum levels of TNF-α and IL-4 were measured in atopic dermatitis mice using ELISA kits, which were observed to be significantly decreased after topical application of FCS. This study demonstrates that the FCS can be used as a potential therapeutic for the treatment and prevention of AD.

The Influence of Phytoconstituents for the Management of Antipsoriatic Activity in Various Animal Models

It is possible for psoriasis to manifest at any point in a person's life, regardless of their age, gender, or geographic location. It is a chronic immune-linked inflammatory skin illness that affects individuals of various racial and ethnic origins. It is recognized to be a longlasting condition. Because of the significant contribution that natural products have made, there has been a significant advancement in the treatment of skin illnesses such as psoriasis. The biggest number of phytochemicals derived from a wide range of plants and herbs are now being used in a variety of applications throughout the whole world. Additionally, a number of phytochemicals, including aloe-emodin, psoralen, curcumin, and others, have been effectively extracted in pure or clear form, and they have shown a great deal of efficacy in the treatment of psoriasis illness. There is evidence that few herbal remedies are effective, and the occurrence of these phytochemicals provides more proof. When synthetic medications are used for chronic therapy, they may cause a variety of adverse consequences; hence, the exploration of natural pharmaceuticals can give a successful natural treatment with a minimal amount of adverse effects. Within the scope of this concise review, a number of plant sources that possess anti-psoriatic activity are investigated, and the antipsoriatic effects of these plant sources are shown on a number of animal models using particular pathways.

Dietary Bioactive Compounds: Implications for Oxidative Stress and Inflammation

Nowadays, it has been amply demonstrated how an appropriate diet and lifestyle are essential for preserving wellbeing and preventing illnesses [...].