Targeting deregulated oxidative stress in skin inflammatory diseases: An update on clinical importance

Circulating biomarkers of oxidative stress in people with acne vulgaris: a systematic review and meta-analysis

The relationship between acne vulgaris and oxidative stress biomarkers lacks a clear consensus. This study aimed to explore the potential correlation between acne vulgaris and circulating oxidative stress biomarkers (superoxide dismutase [SOD], malondialdehyde [MDA], and total antioxidant capacity [TAC]). We searched the PubMed, Embase, and Cochrane Library databases for articles published before June 26, 2023. The literature search combined free words and the medical subject headings terms related to acne vulgaris, SOD, MDA, and TAC. Data were analyzed using Stata 15 software. Additionally, we conducted a subgroup analysis stratified by the severity of acne vulgaris. A total of 14 trials involving 1191 participants were included. Overall results revealed that acne vulgaris was associated with MDA concentrations (SMD = 1.73; 95% CI 1.05, 2.4; P < 0.001). Subgroup analyses indicated that the severity of acne vulgaris was correlated with levels of circulating biomarkers of oxidative stress. TAC concentrations were significantly lower in patients with moderate acne vulgaris compared to controls (SMD =  - 1.37; 95% CI =  - 2.15, - 0.58, P = 0.001). SOD concentrations were significantly lower (SMD =  - 2.92; 95% CI =  - 5.39, - 0.46, P = 0.02) and MDA concentrations were significantly higher (SMD = 2.26; 95% CI = 0.95, 3.57, P = 0.001) in patients with severe acne vulgaris compared to controls. Our results implied that oxidative stress may exist in acne vulgaris. Furthermore, the severity of acne vulgaris was also correlated with oxidative stress.

Nanozyme-Engineered Hydrogels for Anti-Inflammation and Skin Regeneration

Inflammatory skin disorders can cause chronic scarring and functional impairments, posing a significant burden on patients and the healthcare system. Conventional therapies, such as corticosteroids and nonsteroidal anti-inflammatory drugs, are limited in efficacy and associated with adverse effects. Recently, nanozyme (NZ)-based hydrogels have shown great promise in addressing these challenges. NZ-based hydrogels possess unique therapeutic abilities by combining the therapeutic benefits of redox nanomaterials with enzymatic activity and the water-retaining capacity of hydrogels. The multifaceted therapeutic effects of these hydrogels include scavenging reactive oxygen species and other inflammatory mediators modulating immune responses toward a pro-regenerative environment and enhancing regenerative potential by triggering cell migration and differentiation. This review highlights the current state of the art in NZ-engineered hydrogels (NZ@hydrogels) for anti-inflammatory and skin regeneration applications. It also discusses the underlying chemo-mechano-biological mechanisms behind their effectiveness. Additionally, the challenges and future directions in this ground, particularly their clinical translation, are addressed. The insights provided in this review can aid in the design and engineering of novel NZ-based hydrogels, offering new possibilities for targeted and personalized skin-care therapies.

Psoriasis, bone and bowel: a comprehensive review and new insights

Psoriasis is a chronic immune-mediated disorder affecting about 2% of the population worldwide which is associated with significant morbidity. The disease usually presents as raised, well-demarcated erythematous plaques with adherent silvery scales. Psoriasis can appear at any age but it has two peaks occurring at 15–20 and 55–60 years of age. It affects males and females equally. Despite the multitude of investigations about psoriasis and even development of drugs with satisfactory results, its pathogenesis is not fully understood yet and its course is unpredictable. Various environmental triggers, e.g., obesity, stress and drugs may induce disease in genetically susceptible patients. Although psoriasis was considered primarily as a disease of the skin, more investigations have been revealed its systemic nature. Psoriatic arthritis (PsA) may complicate up to one-third of cases of psoriasis vulgaris (PV). Also, the association between psoriasis and a variety of other immune-mediated disorders such as inflammatory bowel disease (IBD) and celiac disease (CD) has been confirmed in various studies. Moreover, a growing body of evidences indicates that psoriasis shares some common histological and phenotypical properties with the spectrum of osteoimmunological diseases such as Paget’s disease of bone (PDB). Thus, exploring the common molecular and genetic mechanisms underlying psoriasis and related disorders is of paramount importance for better elucidating disease pathogenesis and designing more targeted treatments.

Evaluation of systemic oxidative stress in patients with melasma

BACKGROUND

The significance of oxidative stress has been assessed and proven in the etiopathogenesis of many cutaneous disorders, but there are few studies that evaluated the role of only some factors involved in oxidative stress in patients with melasma.

OBJECTIVE

This study aimed to examine the role of oxidative stress in melasma and assess the relationship between systemic oxidative stress and the severity and extension of this disease.

METHODS

In this study, the serum levels of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT), malondialdehyde (MDA), protein carbonyl (PC), selenium (Se), vitamin E (vit E), and vitamin C (vit C) of fifty patients with melasma were compared with those of fifty controls.

RESULTS

The serum level of MDA was significantly higher in the melasma group (3.08 vs. 2.35 U/mL; p < 0.05), and it was positively correlated with the severity (r = 0.4; p < 0.001) and extension (r = 0.3; p < 0.05) of the disease. Furthermore, the serum level of vit C was significantly lower in melasma patients (2.16 vs. 2.57 μg/mL; p < 0.001).

CONCLUSION

Systemic oxidative stress has a key role in the etiopathogenesis of melasma. Serum concentrations of MDA and vitamin C are indicators of this impairment.

Exploring the Phytochemical Composition and Biological Potential of Balkan Endemic Species Stachys scardica Griseb

Stachys scardica Griseb. is a Balkan endemic species listed in The Red Data Book of Bulgaria with the conservation status "endangered". Successful micropropagation was achieved on MS medium supplemented with 1.5 mg/L benzyladenine (BA), followed by a subsequent ex vitro adaptation in an experimental field resulting in 92% regenerated plants. Using nuclear magnetic resonance (NMR), phenylethanoid glycosides (verbascoside, leucosceptoside A), phenolic acids (chlorogenic acid), iridoids (allobetonicoside and 8-OAc-harpagide), and alkaloids (trigonelline) were identified, characteristic of plants belonging to the genus Stachys. High antioxidant and radical scavenging activities were observed in both in situ and ex vitro acclimated S. scardica plants, correlating with the reported high concentrations of total phenols and flavonoids in these variants. Ex vitro adapted plants also exhibited a well-defined anti-inflammatory potential, demonstrating high inhibitory activity against the complement system. Employing a disk diffusion method, a 100% inhibition effect was achieved compared to positive antibiotic controls against Staphylococcus epidermidis and Propionibacterium acnes, with moderate activity against Bacillus cereus. The induced in vitro and ex vitro model systems can enable the conservation of S. scardica in nature and offer future opportunities for the targeted biosynthesis of valuable secondary metabolites, with potential applications in the pharmaceutical and cosmetic industries.

Tart Cherry (Prunus cerasus L.) Pit Extracts Protect Human Skin Cells against Oxidative Stress: Unlocking Sustainable Uses for Food Industry Byproducts

Industrial processing of tart cherries (Prunus cerasus L.) produces bioproducts like cherry pits (CP), which contribute to adverse environmental effects. To identify sustainable strategies to minimize the environmental impact of cherry processing, we investigated their potential value as antioxidants for prospective utilization within cosmeceutical applications. Untargeted metabolomic analyses of water and water: ethanol CP extracts using an eco-friendly technique revealed significant enrichment in coumaroyl derivatives and flavonoids with congruent metabolite representation regardless of the extraction solvent. The antioxidant activity of tart CP extracts was evaluated on human skin cells exposed to H2O2 or LPS, modeling environmentally induced oxidants. Notably, both CP extracts provide antioxidant activity by reducing H2O2 or LPS-induced ROS in human skin keratinocytes without affecting cell viability. The CP extracts increased the expression of CAT and SOD1 genes encoding antioxidant regulatory enzymes while decreasing the expression of NOS2, a pro-oxidant regulator. These findings reveal the antioxidant properties of tart CP, offering new opportunities to produce natural-based skin care products and adding economic value while providing sustainable options to reduce the environmental impact of food byproducts.

Signaling mechanisms underlying lymphatic vessel dysfunction in skin aging and possible anti-aging strategies

Aging-related skin diseases are gradually increasing due to the imbalance of cutaneous homeostasis in the aging population. Skin aging-induced inflammation promotes systemic inflammation and may lead to whole-body aging. Lymphatic vessels play an important role in maintaining fluid and homeostasis balance. In intrinsically aged skin, the number of lymphatic vessels decrease and their functions decline, which is related to the reduced adhesion junctions between lymphatic endothelial cells, particularly VE-cadherin. VEGFC/VEGFR-3 signal pathway plays an important role in remodeling and expansion of lymphatic vessels; the downregulation of this pathway contributes to the dysfunction of lymphatic vessels. Meanwhile, we proposed some additional mechanisms. Decline of the pumping activity of lymphatic vessels might be related to age-related changes in extracellular matrix, ROS increase, and eNOS/iNOS disturbances. In extrinsically aged skin, the hyperpermeability of lymphatic vessels results from a decrease in endothelial-specific tight junction molecules, upregulation of VEGF-A, and downregulation of the VEGFC/VEGFR-3 signaling pathway. Furthermore, some of the Phyto therapeutics could attenuate skin aging by modulating the lymphatic vessels. This review summarized the lymphatic vessel dysfunction in skin aging and anti-aging strategies based on lymphatic vessel modulation.

Excessive Production of Hydrogen Peroxide in Mitochondria Contributes to Atopic Dermatitis

Atopic dermatitis (AD) is a complex disease characterized by chronic recurring eczema and pruritus. In addition, patients with AD display increased cutaneous and systemic levels of oxidative damage markers, whose source remains elusive. In this study, we investigated oxidative and mitochondrial stress in AD epidermis. The levels of superoxide dismutase 2 and hydrogen peroxide are augmented in the mitochondria of flaky tail (ft/ft) mouse keratinocytes, which is associated with the inhibition of the glutathione system and catalase. Furthermore, reduced levels of glutathione peroxidase 4 are associated with accumulation of malondialdehyde, 4-hydroxy-2-nonenal, and oxidized phosphatidylcholines in ft/ft epidermis. Cytochrome c is markedly increased in ft/ft epidermis, hence showing mitochondrial stress. Topical application of MitoQ, which is a mitochondrial-targeting antioxidant, to ft/ft mouse skin reduced damage to macromolecules and inflammation and restored epidermal homeostasis. Absence of alteration in the expression of superoxide dismutase 2, catalase, and glutathione peroxidase 4 and limited lipid peroxidation as well as oxidized phosphatidylcholines in the epidermis of Flg-/- mice suggest that FLG deficiency marginally contributes to oxidative stress in ft/ft epidermis. Increased superoxide dismutase 2, lipid peroxidation, and cytochrome c in the epidermis of patients with AD, associated with reduced antioxidant response in primary AD keratinocytes, corroborate mitochondrial dysfunction and lack of cellular adjustment to oxidative stress in AD epidermis.

More Than Pigments: The Potential of Astaxanthin and Bacterioruberin-Based Nanomedicines

Carotenoids are natural products regulated by the food sector, currently used as feed dyes and as antioxidants in dietary supplements and composing functional foods for human consumption. Of the nearly one thousand carotenoids described to date, only retinoids, derived from beta carotene, have the status of a drug and are regulated by the pharmaceutical sector. In this review, we address a novel field: the transformation of xanthophylls, particularly the highly marketed astaxanthin and the practically unknown bacterioruberin, in therapeutic agents by altering their pharmacokinetics, biodistribution, and pharmacodynamics through their formulation as nanomedicines. The antioxidant activity of xanthophylls is mediated by routes different from those of the classical oral anti-inflammatory drugs such as corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs): remarkably, xanthophylls lack therapeutic activity but also lack toxicity. Formulated as nanomedicines, xanthophylls gain therapeutic activity by mechanisms other than increased bioavailability. Loaded into ad hoc tailored nanoparticles to protect their structure throughout storage and during gastrointestinal transit or skin penetration, xanthophylls can be targeted and delivered to selected inflamed cell groups, achieving a massive intracellular concentration after endocytosis of small doses of formulation. Most first reports showing the activities of oral and topical anti-inflammatory xanthophyll-based nanomedicines against chronic diseases such as inflammatory bowel disease, psoriasis, atopic dermatitis, and dry eye disease emerged between 2020 and 2023. Here we discuss in detail their preclinical performance, mostly targeted vesicular and polymeric nanoparticles, on cellular models and in vivo. The results, although preliminary, are auspicious enough to speculate upon their potential use for oral or topical administration in the treatment of chronic inflammatory diseases.

Recent Advances in Stimuli-Responsive Hydrogel-Based Wound Dressing

Polymeric materials have found increasing use in biomedical applications in the last decades. Among them, hydrogels represent the chosen class of materials to use in this field, in particular as wound dressings. They are generally non-toxic, biocompatible, and biodegradable, and they can absorb large amounts of exudates. Moreover, hydrogels actively contribute to skin repair promoting fibroblast proliferation and keratinocyte migration, allowing oxygen to permeate, and protecting wounds from microbial invasion. As wound dressing, stimuli-responsive systems are particularly advantageous since they can be active only in response to specific environmental stimuli (such as pH, light, ROS concentration, temperature, and glucose level). In this review, we briefly resume the human skin's structure and functions, as well as the wound healing phases; then, we present recent advances in stimuli-responsive hydrogels-based wound dressings. Lastly, we provide a bibliometric analysis of knowledge produced in the field.

Design and Evaluation of Paeonol-Loaded Liposomes in Thermoreversible Gels for Atopic Dermatitis

Paeonol (PAE) is a hydrophobic drug. In this study, we encapsulated paeonol in a lipid bilayer of liposomes (PAE-L), which delayed drug release and increased drug solubility. When PAE-L was dispersed in gels (PAE-L-G) based on a poloxamer matrix material for local transdermal delivery, we observed amphiphilicity, reversible thermal responsiveness, and micellar self-assembly behavior. These gels can be used for atopic dermatitis (AD), an inflammatory skin disease, to change the surface temperature of the skin. In this study, we prepared PAE-L-G at an appropriate temperature for the treatment of AD. We then assessed the gel’s relevant physicochemical properties, in vitro cumulative drug release, and antioxidant properties. We found that PAE-loaded liposomes could be designed to increase the drug effect of thermoreversible gels. At 32 °C, PAE-L-G could change from solution state to gelatinous state at 31.70 ± 0.42 s, while the viscosity was 136.98 ± 0.78 MPa.S and the free radical scavenging rates on DPPH and H2O2 were 92.24 ± 5.57% and 92.12 ± 2.71%, respectively. Drug release across the extracorporeal dialysis membrane reached 41.76 ± 3.78%. In AD-like mice, PAE-L-G could also relieve skin damage by the 12th day. In summary, PAE-L-G could play an antioxidant role and relieve inflammation caused by oxidative stress in AD.

Phytocannabinoids in the Pharmacotherapy of Psoriasis

Phytocannabinoids are naturally occurring compounds, the main source of which is Cannabis sativa L. Through direct action or interaction with G protein-coupled receptors, they affect ROS and pro-inflammatory cytokines levels and modify the effectiveness of transcription factor responsible for the biosynthesis of antioxidants which lead to oxidative stress and its consequences. Due to the modification of the redox balance and inflammation, phytocannabinoids are used in the treatment of various diseases, including autoimmune dermatoses, such as atopic dermatitis and psoriasis. Psoriasis is one of the most common dermatoses, and one of unknown etiology. A disturbed redox balance with a shift towards the oxidation leads to oxidative stress, resulting in oxidative modifications, mainly of lipids and proteins, and prolonged activation of immune cells and increased generation of pro-inflammatory cytokines, resulting in chronic inflammation. Given the biological activity of phytocannabinoids, they have become the focus of research as components of pharmacotherapy for psoriasis. Beneficial effects were shown by various representatives of phytocannabinoids, but the effect of cannabidiol (CBD) on skin cells (in vitro and ex vivo) and on blood cells from patients with psoriasis vulgaris and psoriatic arthritis has been most often evaluated in recent years.

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.

Fermented Taiwanofungus camphoratus Extract Ameliorates Psoriasis-Associated Response in HaCaT Cells via Modulating NF-𝜅B and mTOR Pathways

Psoriasis is a chronic autoimmune disease, and until now, it remains an incurable disease. Therefore, the development of new drugs or agents that ameliorate the disease will have marketing potential. Taiwanofungus camphoratus (TC) is a specific fungus in Taiwan. It is demonstrated to have anticancer, anti-inflammation, and hepatoprotective effects. However, the effects of TC fermented extract on psoriasis are under investigation. In this research, we studied the ability of TC on antioxidative activity and the efficacy of TC on interleukin-17 (IL-17A)-induced intracellular oxidative stress, inflammation-relative, and proliferation-relative protein expression in human keratinocytes. The results of a DPPH radical scavenging assay, reducing power assay, and hydroxyl peroxide inhibition assay indicated that TC has a potent antioxidant ability. Furthermore, TC could reduce IL-17A-induced intracellular ROS generation and restore the NADPH level. In the investigation of pathogenesis, we discovered TC could regulate inflammatory and cell proliferation pathways via p-IKKα/p-p65 and p-mTOR/p-p70S6k signaling pathways in human keratinocytes. In conclusion, TC showed characteristics such as antioxidant, anti-inflammatory, and anti-psoriatic-associated responses. It is expected to be developed as a candidate for oxidative-stress-induced skin disorders or psoriasis treatment.

Allergic Inflammation: Effect of Propolis and Its Flavonoids

The incidence of allergic diseases and their complications are increasing worldwide. Today, people increasingly use natural products, which has been termed a "return to nature". Natural products with healing properties, especially those obtained from plants and bees, have been used in the prevention and treatment of numerous chronic diseases, including allergy and/or inflammation. Propolis is a multi-component resin rich in flavonoids, collected and transformed by honeybees from buds and plant wounds for the construction and adaptation of their nests. This article describes the current views regarding the possible mechanisms and multiple benefits of flavonoids in combating allergy and allergy-related complications. These benefits arise from flavonoid anti-allergic, anti-inflammatory, antioxidative, and wound healing activities and their effects on microbe-immune system interactions in developing host responses to different allergens. Finally, this article presents various aspects of allergy pathobiology and possible molecular approaches in their treatment. Possible mechanisms regarding the antiallergic action of propolis on the microbiota of the digestive and respiratory tracts and skin diseases as a method to selectively remove allergenic molecules by the process of bacterial biotransformation are also reported.