NRF2, a crucial modulator of skin cells protection against vitiligo, psoriasis, and cancer

Pharmacological mechanisms of puerarin in the treatment of Parkinson's disease: An overview

Puerarin, a monomer of traditional Chinese medicine, is a key component of Pueraria radix. Both clinical and experimental researches demonstrated that puerarin has therapeutic effects on Parkinson's disease (PD). Puerarin's pharmacological mechanisms include: 1) Anti-apoptosis. Puerarin inhibits cell apoptosis through the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (Akt) and c-Jun N-terminal kinase (JNK) signaling pathways. Puerarin also exerts a hormone-like effect against cell apoptosis; 2) Anti-oxidative stress injury. Puerarin inhibits the Nrf2 nuclear exclusion through the GSK-3β/Fyn pathway to promote the Nrf2 accumulation in the nucleus, and then promotes the antioxidant synthesis through the Nrf2/ARE signaling pathway to protect against oxidative stress; 3) Neuroprotective effects by intervening in the ubiquitin-proteasome system (UPS) and autophagy-lysosomal pathway (ALP). Puerarin significantly enhances the activity of chaperone-mediated autophagy (CMA), which downregulates the expression of α-synuclein, reduces its accumulation, and thus improves the function of damaged neurons. Additionally, puerarin increases proteasome activity and decreases ubiquitin-binding proteins, thereby preventing toxic accumulation of intracellular proteins; 4) Alleviating inflammatory response. Puerarin inhibits the conversion of microglia to the M1 phenotype while inducing the transition of microglia to the M2 phenotype. Furthermore, puerarin promotes the secretion of anti-inflammatory factor and inhibits the expression of pro-inflammatory factors; 5) Increasing the levels of dopamine and its metabolites. Puerarin could increase the levels of dopamine, homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) in the striatum; 6) Promoting neurotrophic factor expression and neuronal repair. Puerarin increases the expression of glial cell-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), thereby exerting a neuroprotective effect. Moreover, the regulation of the gut microbiota by puerarin may be a potential mechanism for the treatment of PD. The current review discusses the molecular mechanisms of puerarin, which may provide insight into the active components of traditional Chinese medicine in the treatment of PD.

Exploration of the mechanism of Qinglongyi-Buguzhi drug pair in treating vitiligo based on network pharmacology, molecular docking and experimental verification

ETHNOPHARMACOLOGICAL RELEVANCE

The Qinglongyi-Buguzhi herbal pair (QB) is one of commonly used herbal combinations for treating vitiligo in traditional Chinese medicine, consisting of the exocarp of the immature fruit of Juglans regia L. or Juglans mandshurica Maxim., and dried, mature fruit of Psoralea corylifolia L. However, the active components and potential mechanisms of QB in the treatment of vitiligo are still unclear.

AIM OF THE STUDY

The purpose of this study is to clarify the effects and mechanisms of QB on vitiligo treatment through integration of network pharmacology and empirical examinations.

MATERIALS AND METHODS

The active components and targets of QB as well as the targets linked to vitiligo were obtained from network databases. Visualization networks were constructed with Cytoscape 3.9.1. GO and KEGG enrichment analysis were conducted to investigate the possible mechanism. Molecular docking was employed to evaluate the binding affinities between the primary active ingredients of QB and essential targets of the PI3K/Akt/Nrf2 pathway. In vivo and in vitro experiments were carried out to confirm the results of network pharmacology.

RESULTS

We evaluated 44 active compounds and 602 genes from QB, and 107 of these genes linked to vitiligo. GO analysis suggested QB might lessen vitiligo by regulating oxidative stress. KEGG pathway analysis indicated the PI3K/Akt pathway may be crucial for treating vitiligo. Molecular docking results demonstrated the key active ingredients of QB had good binding activity with the major targets in the PI3K/Akt/Nrf2 pathway. In vivo, QB significantly ameliorated vitiligo model mouse's skin pathologies by reducing ROS, elevating CAT and SOD levels. Western blot showed that QB increased the phosphorylation of PI3K and Akt and the expressions of Nrf2 and HO-1 in the skin. In vitro, QB reversed H2O2-induced oxidative injury of melanocytes, enhanced cell survival rate, reduced ROS level, upregulated SOD and CAT activities, and raised the content of melanin. Moreover, QB upregulated the expression levels of Akt, Nrf2, HO-1 mRNA, Akt phosphorylation, HO-1, and nuclear Nrf2 proteins, and also encouraged the nuclear translocation of Nrf2. However, LY294002 treatment significantly reversed the regulatory effect of QB on oxidative damage of melanocytes.

CONCLUSIONS

This study revealed that the therapeutic effect of QB on vitiligo was achieved through multiple components, targets and pathways. Experimental investigation demonstrated that QB could improve vitiligo via reducing oxidative stress, which was probably accomplished by activating the PI3K/Akt/Nrf2 signaling pathway.

Alenizi F, Varzeghani AN, Asghari P, Darwesh A, Malik MH, Lee SW. A model for skin cancer using combination of ensemble learning and deep learning

Skin cancer has a significant impact on the lives of many individuals annually and is recognized as the most prevalent type of cancer. In the United States, an estimated annual incidence of approximately 3.5 million people receiving a diagnosis of skin cancer underscores its widespread prevalence. Furthermore, the prognosis for individuals afflicted with advancing stages of skin cancer experiences a substantial decline in survival rates. This paper is dedicated to aiding healthcare experts in distinguishing between benign and malignant skin cancer cases by employing a range of machine learning and deep learning techniques and different feature extractors and feature selectors to enhance the evaluation metrics. In this paper, different transfer learning models are employed as feature extractors, and to enhance the evaluation metrics, a feature selection layer is designed, which includes diverse techniques such as Univariate, Mutual Information, ANOVA, PCA, XGB, Lasso, Random Forest, and Variance. Among transfer models, DenseNet-201 was selected as the primary feature extractor to identify features from data. Subsequently, the Lasso method was applied for feature selection, utilizing diverse machine learning approaches such as MLP, XGB, RF, and NB. To optimize accuracy and precision, ensemble methods were employed to identify and enhance the best-performing models. The study provides accuracy and sensitivity rates of 87.72% and 92.15%, respectively.

Ex Vivo Analysis of Cell Differentiation, Oxidative Stress, Inflammation, and DNA Damage on Cutaneous Field Cancerization

Cutaneous field cancerization (CFC) refers to a skin region containing mutated cells' clones, predominantly arising from chronic exposure to ultraviolet radiation (UVR), which exhibits an elevated risk of developing precancerous and neoplastic lesions. Despite extensive research, many molecular aspects of CFC still need to be better understood. In this study, we conducted ex vivo assessment of cell differentiation, oxidative stress, inflammation, and DNA damage in CFC samples. We collected perilesional skin from 41 patients with skin cancer and non-photoexposed skin from 25 healthy control individuals. These biopsies were either paraffin-embedded for indirect immunofluorescence and immunohistochemistry stain or processed for proteins and mRNA extraction from the epidermidis. Our findings indicate a downregulation of p53 expression and an upregulation of Ki67 and p16 in CFC tissues. Additionally, there were alterations in keratinocyte differentiation markers, disrupted cell differentiation, increased expression of iNOS and proinflammatory cytokines IL-6 and IL-8, along with evidence of oxidative DNA damage. Collectively, our results suggest that despite its outwardly normal appearance, CFC tissue shows early signs of DNA damage, an active inflammatory state, oxidative stress, abnormal cell proliferation and differentiation.

Sulforaphane alleviates psoriasis by enhancing antioxidant defense through KEAP1-NRF2 Pathway activation and attenuating inflammatory signaling

Psoriasis is a chronic inflammatory skin disease that affects millions of people worldwide. Sulforaphane (SFN) has been shown to have anti-inflammatory and antioxidant properties. In this study, we investigated the effects of SFN on a mouse model of psoriasis induced by imiquimod (IMQ) and its underlying molecular mechanism. Mice treated with SFN showed significant improvement in psoriatic symptoms, including reduced erythema, scales, and cutaneous thickness. Histopathological analysis and immunohistochemical staining revealed decreased expression of K16, K17, and Ki67 in SFN-treated mice, indicating reduced abnormal differentiation of keratinocytes and cutaneous inflammation. SFN treatment also reduced the activation of STAT3 and NF-κB pathways and downregulated pro-inflammatory cytokines IL-1β, IL-6, and CCL2. In vitro experiments using HaCaT cells demonstrated that SFN inhibited IL-22 and TNF-α-induced activation of inflammatory pathways and keratinocyte proliferation. Network pharmacology analysis suggested that the KEAP1-NRF2 pathway might be involved in the protective effects of SFN on psoriasis. We observed reduced NRF2 expression in human psoriatic lesions, and subsequent experiments showed that SFN activated KEAP1-NRF2 pathway in vivo and in vitro. Importantly, NRF2-deficient mice exhibited aggravated psoriasis-like symptoms and reduced response to SFN treatment. Our findings indicate that SFN ameliorates psoriasis symptoms and inflammation through the KEAP1-NRF2 pathway, suggesting a potential therapeutic role for SFN in the treatment of psoriasis.

In vitro and in vivo evaluation of alginate hydrogel-based wound dressing loaded with green chemistry cerium oxide nanoparticles

Interactive wound dressings have displayed promising outcomes in enhancing the wound healing process. This study focuses on creating a nanocomposite wound dressing with interactive and bioactive properties, showcasing potent antioxidant effects. To achieve this, we developed cerium oxide nanoparticles utilizing curcumin as both the reducing and capping agent. Characterization techniques such as SEM, EDX, DLS, Zetasizer, FTIR, and XRD were utilized to analyze the cerium oxide nanoparticles synthesized through a green approach. The image analysis on the obtained TEM images showed that the curcumin-assisted biosynthesized CeO2NPs have a size of 18.8 ± 4.1 nm. The peaks located at 28.1, 32.7, 47.1, 56.0, 58.7, 69.0, and 76.4 correspond to (111), (200), (220), (311), (222), (400), and (331) crystallographic planes. We applied the Debye-Scherrer equation and observed that the approximate crystallite size of the biosynthesized NPs is around 8.2 nm based on the most intensive broad Bragg peak at 28.1°. The cerium oxide nanoparticles synthesized were integrated into an alginate hydrogel matrix, and the microstructure, porosity, and swelling behavior of the resulting wound dressing were assessed. The characterization analyses provided insights into the physical and chemical properties of the green-synthesized cerium oxide nanoparticles and the alginate hydrogel-based wound dressing. In vitro studies demonstrated that the wound dressing based on alginate hydrogel exhibited favorable antioxidant properties and displayed hemocompatibility and biocompatibility. Animal studies conducted on a rat full-thickness skin wound model showed that the alginate hydrogel-based wound dressing effectively accelerated the wound healing process. Overall, these findings suggest that the alginate hydrogel-based wound dressing holds promise as a highly effective material for wound healing applications.

Specific Activation of CB2R Ameliorates Psoriasis-Like Skin Lesions by Inhibiting Inflammation and Oxidative Stress

Psoriasis is a chronic inflammatory skin disease. Inflammation and oxidative stress play crucial roles in the pathogenesis of psoriasis. Cannabinoid receptor type 2 (CB2R) is an attractive target for treating various inflammatory disorders. However, the precise role and mechanism of CB2R activation in psoriasis remain to be further elucidated. In this study, imiquimod (IMQ)-induced experimental psoriasis mice and tumor necrosis factor-α (TNF-α)-activated keratinocytes (HaCaT) were used to examine the effect of CB2R activation on psoriasis-like lesions and the mechanism in vivo and in vitro. Our results demonstrated that activation of CB2R by the specific agonist GW842166X (GW) significantly ameliorated IMQ-induced psoriasiform skin lesions in mice by reducing epidermal thickness and decreasing plaque thickness. On the one hand, GW alleviated inflammation by decreasing inflammatory cytokines and abating inflammatory cell infiltration. On the other hand, this treatment reduced the level of iNOS and downregulated the expression of CB2R in psoriatic skin tissue. Further studies suggested that the Kelch-like ECH-associated protein 1/nuclear factor erythroid-2-related factor (Keap1/Nrf2) signaling pathway might be involved. Our findings reveal that selective activation of CB2R may serve as a new strategy for the treatment of psoriasis.

Alopecia Areata: A Review of the Role of Oxidative Stress, Possible Biomarkers, and Potential Novel Therapeutic Approaches

Alopecia areata (AA) is a dermatological condition characterized by non-scarring hair loss. Exact etiopathogenesis of AA is still unknown although it is known that several factors contribute to the collapse of the hair-follicle (HF)-immune-privileged (IP) site. Oxidative stress (OS) plays an important role in skin diseases. The aim of this review was to clarify the role of OS in AA pathogenesis and diagnosis, and to discuss potential treatment options. Oxidative-stress markers are altered in serum and skin samples of patients with AA, confirming a general pro-oxidative status in patients with AA. OS induces MHC class I chain-related A (MICA) expression in HF keratinocytes that activates the receptor NKG2D, expressed in NK cells and CD8+ T cytotoxic cells leading to destabilization of the HF immune-privileged site through the production of IFN-γ that stimulates JAK1 and JAK2 pathways. OS also activates the KEAP1-NRF2 pathway, an antioxidant system that contributes to skin homeostasis. In addition, a decrease of ATG5 and LC3B in the hair matrix and an increase in p62 levels indicates a reduction of intrafollicular autophagy during the evolution of AA. Potential biomarkers of OS in AA could be: malondialdehyde (MDA), advanced glycation end-products (AGEs), and ischemic-modified albumin (IMA). JAK inhibitors are the new frontier in treatment of AA and the use of nutraceuticals that modulate the OS balance, in combination with standard treatments, represent promising therapeutic tools.

Oxidative Stress and Phototherapy in Atopic Dermatitis: Mechanisms, Role, and Future Perspectives

Atopic dermatitis is a chronic inflammatory skin disease in which the overproduction of reactive oxygen species plays a pivotal role in the pathogenesis and persistence of inflammatory lesions. Phototherapy represents one of the most used therapeutic options, with benefits in the clinical picture. Studies have demonstrated the immunomodulatory effect of phototherapy and its role in reducing molecule hallmarks of oxidative stress. In this review, we report the data present in literature dealing with the main signaling molecular pathways involved in oxidative stress after phototherapy to target atopic dermatitis-affected cells. Since oxidative stress plays a pivotal role in the pathogenesis of atopic dermatitis and its flare-up, new research lines could be opened to study new drugs that act on this mechanism, perhaps in concert with phototherapy.