Protease-activated receptor 2 induces ROS-mediated inflammation through Akt-mediated NF-κB and FoxO6 modulation during skin photoaging

Diosmetin attenuates the ubiquitination of epidermal hypoxia-inducible factor 1 alpha by diminishing the formation of RhoBTB3/PHD2 complex in ultraviolet radiation-induced sunburn in mice

BACKGROUND

The accumulation of excessive reactive oxygen species (ROS) in keratinocytes is a pivotal mechanism underlying ultraviolet radiation (UVR)-induced skin damage and carcinogenesis. Disruption of redox homeostasis exacerbates ROS levels and instigates inflammation. Hypoxia-inducible factor 1 alpha (HIF-1α), essential for maintaining redox balance, is expressed in keratinocytes and plays a protective role in preserving the skin barrier. Stabilization of HIF-1α presents a potential therapeutic approach for UVR-induced sunburn. Our observations indicate that diosmetin inhibits the hydroxylation and ubiquitination of HIF-1α in UVR-induced sunburn. However, the precise mechanisms remain unclear.

PURPOSE

This study aims to elucidate the role and underlying mechanisms of diosmetin in the context of UVR-induced skin sunburn.

METHODS

In vivo UVR-induced sunburn mice models and in vitro UVR-exposed HaCaT cell models were established. We employed histopathological grade, oxidative stress assessment, ROS production measurement, and immunofluorescence staining of inflammatory markers to evaluate the activity of diosmetin. Additionally, RNA sequencing assay and co-immunoprecipitation assays were conducted to elucidate the underlying mechanisms. To verify the role of Rho Binding BTB Protein 3 (RhoBTB3), we performed intradermal injection rAAV-RhoBTB3-GFP to overexpress of RhoBTB3in mice.

RESULTS

Diosmetin effectively inhibits the hydroxylation and ubiquitination of HIF-1α, resulting in significant antioxidative and anti-inflammatory effects in UVR-induced sunburn. RNA sequencing analysis and co-immunoprecipitation experiments demonstrated that diosmetin reduces the formation of the RhoBTB3/PHD2 complex, thereby modulating the ubiquitination of HIF-1α and mitigating oxidative stress. Immunohistochemical analysis conducted on the wild-type and RhoBTB3-overexpressing mice revealed an enrichment of RhoBTB3, Prolyl Hydroxylase Domain protein 2 (PHD2), and HIF-1α in the epidermis. Notably, diosmetin stabilizes the HIF-1α protein and reduces oxidative stress by limiting the formation of the RhoBTB3/PHD2 complex in the epidermis of mice.

CONCLUSIONS

Our study suggests that diosmetin acts as a regulator of the RhoBTB3/PHD2/HIF-1α axis to alleviate oxidative stress in sunburn, providing novel insights into potential treatments and mechanisms for sunburn.

Light-Controlled Small Extracellular Vesicle-Based Spherical Nucleic Acid Nanomotor for Enhanced Transdermal Delivery against Skin Aging

Small extracellular vesicles (sEV) derived from mesenchymal stem cells hold promise for anti-skin aging, yet their clinical application is hindered by poor transdermal permeability. Herein, we report an innovative light-controlled sEV-based spherical nucleic acid nanomotor (NM-ESNA). This nanosystem was composed of an sEV core and an MMP1-targeting siRNA shell, forming a 3D penetrative nanostructure. In addition, asymmetrically modified light-responsive gas-generating molecules were integrated into the nanomotor, enabling efficient dermal delivery. The light-controlled and enhanced transdermal delivery guaranteed synergistic anti-skin aging therapy through sEV-mediated paracrine effects and gene therapy targeting MMP1 in the dermis. On the basis of this deep transdermal delivery technology and the synergistic therapy strategy, NM-ESNA demonstrated outstanding anti-skin aging effects in a mouse model. This biocompatible nanosystem (NM-ESNA) enabled light-controlled and deep transdermal delivery, establishing a therapeutic platform with significant potential for sEV-based noninvasive anti-skin aging therapy.

Evaluation of skin cancer prevention properties of probiotics

Bacteria play a crucial role in human health and disease pathogenesis. In recent years, the therapeutic potential of probiotics has gained increasing attention, with studies suggesting their application in treating various diseases, including cancer. We evaluated clinical data supporting the use of oral and topical probiotics for skin malignancies by conducting a literature search in PubMed and Google Scholar. Although limited, clinical trials investigating probiotics in cancer prevention and treatment have shown promising results, particularly in controlling tumor progression and enhancing therapeutic outcomes. Emerging research suggests that probiotics may contribute to skin cancer prevention by modulating the gut and skin microbiomes, enhancing immune responses, exerting antioxidant and anti-inflammatory effects, and inducing apoptosis. Given their antiproliferative and pro-apoptotic effects on carcinoma cells, probiotic-based therapies may serve as potential cancer-preventive agents and adjunctive treatments during conventional therapies. Key findings from our review highlight the ability of probiotics to influence cancer progression through immune regulation, apoptosis induction, and modulation of inflammatory pathways. However, further well-designed clinical trials are needed to validate these findings and establish probiotics as a viable therapeutic approach in oncology.

Therapeutic Potential of Chick Early Amniotic Fluid in Mitigating Ionizing-Radiation-Induced Damage

Background: Clinical data indicate that at least half of patients with malignancies receive radiotherapy. While radiotherapy effectively kills tumor cells, it is also associated with significant ionizing radiation (IR) damage. Moreover, the increasing emissions of nuclear pollutants raise concerns about the potential exposure of more individuals to the risks associated with IR. The Chinese term for amniotic fluid (AF) is rooted in the Yin-Yang theory of traditional Chinese medicine, where it symbolizes the inception of human life. Chick early AF (ceAF), a natural product, has shown promise in the field of regenerative medicine. There have been no studies investigating the potential efficacy of ceAF in the treatment of IR-induced damage. This study aims to assess the therapeutic potential of ceAF in alleviating IR-induced damage and elucidate its potential molecular mechanism. Methods: In vivo experiments were conducted on 8-week-old male C57BL/6J mice to investigate the effects of ceAF in a radiation injury model induced by whole-body irradiation with X-rays (6 Gy) for 5 min. The ceAF was extracted from chicken embryos aged 7-9 days. Results: We found that the supplementation of ceAF reduces mortality induced by IR, improves exercise capacity in IR mice, and reverses IR-induced skin damage. IR leads to varying degrees of volume atrophy and weight loss in the major internal organs of mice. However, ceAF intervention effectively mitigates IR-induced organ damage, with a notable impact on the spleen. The supplementation of ceAF enhances spleen hematopoietic and immune functions by reducing oxidative stress, alleviating inflammatory responses, and preventing splenic DNA damage from IR exposure, ultimately leading to an overall improvement in health. Conclusions: ceAF effectively alleviates body damage induced by IR, and our findings provide new perspectives and therapeutic strategies for mitigating IR-induced damage.

The landscape of N 6-methyladenosine RNA methylation in skin diseases

Skin diseases encompass a diverse range of conditions with significant psychological and physiological impacts. N6-methyladenosine (m6A) RNA methylation is a key epitranscriptomic modification that regulates gene expression by influencing RNA stability, splicing, translation, export and degradation. Recent studies have highlighted the crucial role of m6A modification in the pathogenesis and progression of various skin diseases. m6A modification affects critical biologic processes of the skin, such as inflammation, immune response and cellular ageing. This review systematically explores the landscape of m6A modification in nontumour skin diseases, elucidating its regulatory roles and therapeutic implications, including wound healing, scar and keloid, skin ageing, psoriasis, systemic lupus erythematosus, acne vulgaris, rosacea, chronic actinic dermatitis and scleroderma. The intricate mechanisms of m6A modification can lead to the development of novel diagnostic biomarkers and therapeutic strategies, ultimately improving patient outcomes.

Anti-inflammatory and barrier repair mechanisms of active components in Daemonorops draco Bl. for UVB-induced skin damage

Daemonorops draco Bl. extract and its active ingredients can remove blood stasis and promote muscle and wound healing and are widely used in skin health and other fields. Modern pharmacological studies have demonstrated that this extract exerts excellent anti-inflammatory effects beneficial for skin barrier repair. However, the mechanism of action and monomeric components of D. draco remain unclear. Seven active monomers (XJ-1 ~ XJ-7) were extracted and purified from D. draco. The successful construction of the HaCaT inflammation model was achieved through the detection of IL-1β and TNF-α expressions in UVB-irradiated HaCaT cells. Based on this cellular model, (2 S)-5-methoxy-6-methylflavan-7-ol (XJ-2) was determined to be the best-screened monomer. The effects of XJ-2 on the production of reactive oxygen species (ROS) and Ca2+ in HaCaT cells were investigated using fluorescent probes and flow cytometry, respectively. The impact of XJ-2 on the expression of crucial proteins within the NF-κB pathway was examined via immunofluorescence and western blotting. The expression levels of downstream inflammatory factors, namely IL-1β and TNF-α, were detected through PCR. The effects of XJ-2 on the expression of skin barrier-related factors filaggrin (FLG), aquaporin 3 (AQP-3), and claudin1 (CLDN1) were investigated using PCR, immunofluorescence, and western blotting. Based on these findings, we comprehensively examined the mechanisms underlying the anti-inflammatory and barrier repair effects of XJ-2. XJ-2 primarily protected the internal structure and function of the cells by inhibiting the mass production of ROS and Ca2+ inflow. XJ-2 exerts anti-inflammatory effects by regulating the key proteins of the NF-κB/IKKα pathway and reducing the expression of inflammatory factors. XJ-2 repairs skin barrier damage by regulating multiple factors. Compound XJ-2 from D. draco exerts excellent anti-inflammatory and barrier repair effects, possesses great potential for the treatment of skin diseases, and can be used as a dermatological drug to repair skin barrier damage.

Dexmedetomidine Reduces Chronic Stress-Related Thrombosis in a Mouse FeCl3 Model

Chronic psychological stress (CPS) is a significant risk factor for thrombotic cardio-cerebrovascular diseases (TCVDs). Clinical data suggest that the α2-adrenergic receptor (AdR-α2) agonist dexmedetomidine (Dex) can influence coagulation in stress-exposed intensive care unit patients. Given the important role of protease-activated receptor-2 (PAR-2) in vascular pathobiology, we aimed to investigate the potential effects of Dex on stress-related thrombus formation, focusing on the PAR-2 signaling pathway. Eight-week-old male mice underwent non-stress and immobilization stress with Dex treatment for 2 weeks and were then subjected to carotid artery thrombosis induction using ferric chloride (FeCl3). On Day 14 post-stress, the mice exhibited increased thrombus weight and length, along with harmful alterations in the plasma levels of von Willebrand factor and metalloproteinase with thrombospondin Type 13 motifs. Additionally, arterial protein and/or mRNA levels of PAR-2, p-Akt, Bcl-2, cleaved caspase-3, cytochrome c, gp91phox, TNF-α, MCP-1, ICAM-1, VCAM-1, and TLR-4 were altered, accompanied by arterial endothelial loss. Dex treatment reversed these changes. Conversely, AdR-α2 blockage with yohimbine diminished the benefits of Dex. In vitro, Dex reduced stress serum-induced reactive oxygen species production and endothelial apoptosis, along with beneficial alterations in PAR-2, Bcl-2, and cytochrome c protein levels. Yohimbine diminished these effects. Thus, α2-adrenergic receptor activation appeared to mitigate stress-related thrombus formation in mice undergoing FeCl3-induced surgery, possibly by negatively regulating PAR-2 signaling. These findings suggest a potential therapeutic strategy for CPS-related thrombotic events in patients with TCVDs.

Development and Validation of Ultrasound Hemodynamic-based Prediction Models for Acute Kidney Injury After Renal Transplantation

RATIONALE AND OBJECTIVES

Acute kidney injury (AKI) post-renal transplantation often has a poor prognosis. This study aimed to identify patients with elevated risks of AKI after kidney transplantation.

MATERIALS AND METHODS

A retrospective analysis was conducted on 422 patients who underwent kidney transplants from January 2020 to April 2023. Participants from 2020 to 2022 were randomized to training group (n=261) and validation group 1 (n=113), and those in 2023, as validation group 2 (n=48). Risk factors were determined by employing logistic regression analysis alongside the least absolute shrinkage and selection operator, making use of ultrasound hemodynamic, clinical, and laboratory information. Models for prediction were developed using logistic regression analysis and six machine-learning techniques. The evaluation of the logistic regression model encompassed its discrimination, calibration, and applicability in clinical settings, and a nomogram was created to illustrate the model. SHapley Additive exPlanations were used to explain and visualize the best of the six machine learning models.

RESULTS

The least absolute shrinkage and selection operator combined with logistic regression identified and incorporated five risk factors into the predictive model. The logistic regression model (AUC=0.927 in the validation set 1; AUC=0.968 in the validation set 2) and the random forest model (AUC=0.946 in the validation set 1;AUC=0.996 in the validation set 2) showed good performance post-validation, with no significant difference in their predictive accuracy.

CONCLUSION

These findings can assist clinicians in the early identification of patients at high risk for AKI, allowing for timely interventions and potentially enhancing the prognosis following kidney transplantation.

Dysregulation of autophagy during photoaging reduce oxidative stress and inflammatory damage caused by UV

Photoaging, the premature aging of skin due to chronic ultraviolet (UV) exposure, is a growing concern in dermatology and cosmetic science. While UV radiation is known to induce DNA damage, oxidative stress, and inflammation in skin cells, recent research unveils a promising countermeasure: autophagy. This review explores the intricate relationship between autophagy and photoaging, highlighting how this cellular recycling process can mitigate UV-induced damage. We begin by examining the differential impacts of UVA and UVB radiation on skin cells and the role of oxidative stress in accelerating photoaging. Next, we delve into the molecular mechanisms of autophagy, including its various forms and regulatory pathways. Central to this review is the discussion of autophagy's protective functions, such as the clearance of damaged organelles and proteins, and its role in maintaining genomic integrity. Furthermore, we address the current challenges in harnessing autophagy for therapeutic purposes, including the need for selective autophagy inducers and a deeper understanding of its context-dependent effects. By synthesizing recent advancements and proposing future research directions, this review underscores the potential of autophagy modulation as a novel strategy to prevent and treat photoaging. This comprehensive analysis aims to inspire further investigation into autophagy-based interventions, offering new hope for preserving skin health in the face of environmental stressors.

Alhagi camelorum seed polysaccharide alleviates methylglyoxal-induced skin damage via antioxidant and anti-inflammatory actions

Alhagi camelorum (AC) is an herbal medicine known for its anti-inflammatory and antioxidant properties. However, the mechanism by which AC affects skin aging remains unclear. In this study, a polysaccharide with antioxidant activity was extracted from AC seeds (ACSP). The structure of ACSP was characterized by molecular weight determination, Fourier transform infrared spectroscopy, monosaccharide composition analysis, scanning electron microscopy, and physicochemical analysis. The molecular weight of ACSP was 736,831 Da. ACSP, devoid of a triple-helical conformation, comprised mannose, rhamnose, galacturonic acid, glucose, galactose, and arabinose at a molar ratio of 39.65:0.85:0.59:11.57:40.25:6.60. The anti-skin-aging activity and potential mechanisms of action of ACSP were investigated in vitro. We observed that ACSP delayed the onset of senescence, promoted cell migration, decreased the expression of DNA damage markers and the production of reactive oxygen species, and increased the mitochondrial membrane potential in damaged cells. ACSP also significantly reduced the expression of the inflammatory mediators interleukin (IL)-6, IL-1β, and tumor necrosis factor-α in HaCaT cells. In addition, ACSP attenuated the expression of proteins within the IL-17 signaling pathway and suppressed the phosphorylation of JAK2/STAT3/NF-κB proteins, thereby exerting a senescence-delaying effect on MGO-induced HaCaT cells. In conclusion, we elucidated the potential of ACSP in delaying skin aging and offer a novel plant-derived adjuvant to delay aging.

FOXO6: A unique transcription factor in disease regulation and therapeutic potential

FOXO6, a unique member of the Forkhead box O (FOXO) transcription factor family, has emerged as a pivotal regulator in various physiological and pathological processes, including apoptosis, oxidative stress, autophagy, cell cycle control, and inflammation. Unlike other FOXO proteins, FOXO6 exhibits distinct regulatory mechanisms, particularly its inability to undergo classical nucleocytoplasmic shuttling. These unique properties suggest that FOXO6 may function through alternative pathways, positioning it as a novel research target. This review provides the first comprehensive review of FOXO6's biological functions and its roles in the progression of multiple diseases, such as cancer, metabolic disorders, neurodegenerative conditions, and cardiovascular dysfunction. We highlight FOXO6's interaction with critical signaling pathways, including PI3K/Akt, PPARγ, and TXNIP, and discuss its contributions to tumor progression, glucose and lipid metabolism, oxidative stress, and neuronal degeneration. Moreover, FOXO6's potential as a therapeutic target is explored, with particular emphasis on its ability to modulate drug resistance and its implications for disease treatment. Despite its promising therapeutic potential, the development of FOXO6-targeted therapies remains challenging due to overlapping functions within the FOXO family and the context-dependent nature of FOXO6's regulatory roles. This review underscores the need for further experimental and clinical studies to elucidate the molecular mechanisms underlying FOXO6's functions and to validate its application in disease prevention and treatment. By systematically analyzing current research, this review aims to provide a foundational reference for future studies on FOXO6, paving the way for novel therapeutic strategies targeting this unique transcription factor.

Galvanic Cell Bipolar Microneedle Patches for Reversing Photoaging Wrinkles

Excessive exposure to ultraviolet (UV) radiation is a major factor in the development of skin photoaging wrinkles. While current treatments can slow the progression of photoaging, it is very difficult to achieve complete reversal. This study introduces galvanic cell microneedle (GCMN) patches with magnesium-containing bipolar electrodes. These patches operate through a galvanic cell mechanism, generating microcurrents and releasing hydrogen gas and magnesium ions via a redox reaction. The combination of hydrogen's antioxidant and anti-inflammatory properties, microcurrent-induced stimulation of cell migration, and magnesium's promotion of angiogenesis and macrophage M2 anti-inflammatory polarization synergistically works to reverse photoaging wrinkles and rejuvenate the skin. Furthermore, this work examines how GCMNs may influence the transforming growth factor-β/Smad (TGF-β/Smad) pathway. This approach shows promise for advancing research and development in the field of medical cosmetology.

Innovative Plant Exosome Delivery System for Enhancing Antiaging Potency on Skin

Plant exosomes, small vesicles released by plant cells that contain various bioactive molecules, have garnered great attention for their potential applications in medicine, yet their delivery applications for skincare remain underexploited. Resveratrol (RES), renowned for its remarkable antiaging properties, faces challenges in transdermal absorption due to the stratum corneum barrier, hindering its efficacy. To address this, we developed a delivery system incorporating RES-loaded plant (Leontopodium alpinum) exosome (LEOEXO@RES). Evaluation through both in vitro and in vivo experiments demonstrated LEOEXO@RES's enhanced delivery of bioactive compounds and multifaceted skincare impact. Specifically, this approach not only promoted environmentally responsible waste reuse but also achieved harmonious synergy between LEOEXO carriers and RES, enhancing their overall efficacy. The LEOEXO@RES effectively ameliorated inflammation levels and inhibited cellular senescence, highlighting its promising potential in antiaging skincare applications.

Redox regulation: mechanisms, biology and therapeutic targets in diseases

Redox signaling acts as a critical mediator in the dynamic interactions between organisms and their external environment, profoundly influencing both the onset and progression of various diseases. Under physiological conditions, oxidative free radicals generated by the mitochondrial oxidative respiratory chain, endoplasmic reticulum, and NADPH oxidases can be effectively neutralized by NRF2-mediated antioxidant responses. These responses elevate the synthesis of superoxide dismutase (SOD), catalase, as well as key molecules like nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione (GSH), thereby maintaining cellular redox homeostasis. Disruption of this finely tuned equilibrium is closely linked to the pathogenesis of a wide range of diseases. Recent advances have broadened our understanding of the molecular mechanisms underpinning this dysregulation, highlighting the pivotal roles of genomic instability, epigenetic modifications, protein degradation, and metabolic reprogramming. These findings provide a foundation for exploring redox regulation as a mechanistic basis for improving therapeutic strategies. While antioxidant-based therapies have shown early promise in conditions where oxidative stress plays a primary pathological role, their efficacy in diseases characterized by complex, multifactorial etiologies remains controversial. A deeper, context-specific understanding of redox signaling, particularly the roles of redox-sensitive proteins, is critical for designing targeted therapies aimed at re-establishing redox balance. Emerging small molecule inhibitors that target specific cysteine residues in redox-sensitive proteins have demonstrated promising preclinical outcomes, setting the stage for forthcoming clinical trials. In this review, we summarize our current understanding of the intricate relationship between oxidative stress and disease pathogenesis and also discuss how these insights can be leveraged to optimize therapeutic strategies in clinical practice.

A Triple-Precursor Blend as a Topical Solution to Protect the Skin Against Environmental Damage

The epidermis acts as the body's primary defense, relying on components like lipids, HA and GSH for skin barrier function, hydration and resistance to oxidative stress. However, limitations in the topical application of these biomolecules call for novel approaches. This study investigates the efficacy of Pro-GHL, a blend of free fatty acids, acetylglucosamine and GSH amino acid precursors (GAPs), designed to replenish skin lipids, HA and GSH through de novo biosynthesis. Using primary human keratinocytes, Pro-GHL demonstrated superior antioxidant and anti-inflammatory capacities compared to each individual component under the challenge of UVB or blue light. In 3D skin equivalent models (EpiKutis®), Pro-GHL enhanced skin barrier function. In addition, Pro-GHL prevented the development of pigmentation in pigmented 3D skin equivalent models (MelaKutis®) subjected to UVB irradiation or Benzo[a]pyrene exposure. Together, these results highlight Pro-GHL's potential as a novel, effective and comprehensive skincare approach to fortify the skin's defense system from within and prevent the accumulation of tissue damage in response to extrinsic stressors.

TIMP3 deficiency accelerates UVB-induced HaCaT cell senescence by regulating ferroptosis

Prolonged exposure to ultraviolet B (UVB) light leads to the accumulation of reactive oxygen species (ROS), a key contributor to skin aging. Previous studies have demonstrated that UVB exposure results in a deficiency in the expression of TIMP3 in keratinocytes. The objective of this study was to investigate the specific role of TIMP3 in keratinocytes. UVB-treated HaCaT cells were utilized to establish a cellular photoaging model. We found that UVB significantly increased levels of ROS, promoted senescence and ferroptosis, and inhibited the expression of TIMP3 in HaCaT. This inhibition was notably alleviated by Fer-1, a ferroptosis inhibitor. In addition, the knockdown of TIMP3 in HaCaT enhanced senescence by inducing the ferroptosis. Mechanistically, UVB exposure also led to a decrease in the expression of KLF4, a transcription factor that regulated TIMP3 expression. Futhermore, UVB-induced reduced expression of KLF4 and TIMP3 in vivo. Our results suggest that deletion of the KLF4/TIMP3 axis promotes HaCaT cell senescence by facilitating the progression of ferroptosis. TIMP3 may serve as an effective therapeutic target for preventing skin photoaging.

Astragalin relieves inflammatory pain and negative mood in CFA mice by down-regulating mGluR5 signaling pathway

As a flavonoid compound, astragalin (AST) is found in a variety of medicinal plants. In clinical studies, AST has anti-inflammatory and analgesia effects on rheumatoid arthritis, bronchopneumonia diseases and so on, but its specific role and mechanism is still not clear. This study aimed to investigate the effect and molecular mechanism of AST on inflammatory pain and pain-related emotions in complete Freund's adjuvant (CFA) mice. In this study, we observed that AST significantly alleviated CFA-induced inflammatory pain and associated emotional disturbances in mice. The mechanism may be related to down-regulating mGluR5-mediated PKCλ-ERK1/2-FOXO6 signaling pathway in CFA mice. Treatment with the mGluR5-specific inhibitor MTEP resulted in the downregulation of proteins associated with the PKCλ-ERK1/2-FOXO6 pathway, similar to the effects observed with AST administration. These results suggested that AST might play a crucial role in the management of inflammatory pain and related emotions, shedding light on its underlying mechanism for treating such conditions.

Ultraviolet Light Causes Skin Cell Senescence: From Mechanism to Prevention Principle

The skin is an effective protective barrier that significantly protects the body from damage caused by external environmental factors. Furthermore, skin condition significantly affects external beauty. In today's era, which is of material and spiritual prosperity, there is growing attention on skincare and wellness. Ultraviolet radiation is one of the most common external factors that lead to conditions like sunburn, skin cancer, and skin aging. In this review, several mechanisms of UV-induced skin cell senescence are discussed, including DNA damage, oxidative stress, inflammatory response, and mitochondrial dysfunction, which have their own characteristics and mutual effects. As an illustration, mitochondrial dysfunction triggers electron evasion and the generation of more reactive oxygen species, leading to oxidative stress and the activation of the NLRP3 inflammasome, which in turn causes mitochondrial DNA (mt DNA) damage. Based on the current mechanism, suitable prevention and treatment strategies are proposed from sunscreen, dietary, and experimental medications respectively, aimed at slowing down skin cell aging and providing protection from ultraviolet radiation. The effects of ultraviolet rays on skin is summarized, offering insights and directions for future studies on mechanism of skin cell senescence, with an anticipation of discovering more effective prevention and cure methods.

A bioadhesive antioxidase-overexpressed probiotic prevents radiation enteritis by scavenging the excess reactive oxygen species

The scavenging of the excess reactive oxygen species (ROS) induced by radiation is fundamental for radiation protection. However, directly applying antioxidants results in low bioavailability and side effects. Superoxide dismutase (SOD) and catalase (CAT) have high ROS clearance efficiency, whereas their application is limited by the enzyme inactivation, making it difficult to exhibit significant therapeutic effects. Here, we engineered a probiotic Escherichia coli Nissle 1917 (EcN), i.e., AAEcN, serving as a SOD/CAT vehicle to scavenge ROS for the prevention and treatment of radiation enteritis (RE). The overexpressed Drsod and katE in AAEcN showed 5-fold ROS elimination efficiency compared to the wild EcN. Furthermore, the intestinal retention time of engineered EcN was prolonged through trefoil factor 3 gene (TFF3) modification of curli fibers on the bacterial surface, which contributed to the persistence of antioxidant enzyme activity. We found that AAEcN rapidly eliminated the intracellular ROS induced by radiation. Only a single oral dosing of AAEcN was satisfied to alleviate the radiation damage to the small intestine, colon, and spleen. Moreover, the homeostasis of pro-/anti-inflammatory cytokines was realized. The proliferation of the intestinal stem cells and spleen hematopoietic stem cells was enhanced, while the apoptosis of mucosal cells was inhibited. Our findings suggest valuable insights into the ROS scavenging way in RE, and establish an empirical basis for developing probiotics as an antioxidant enzyme vehicle for the bacteriotherapy of RE.

Atractylodin mitigates UVB radiation-induced oxidative stress and photoaging responses by enhancing NrF2 signaling in human epidermal keratinocytes

This study explores the protective role of Atractylodin (ATN) on ultraviolet-B (UVB) radiation-exposed oxidative damage and photoaging responses in human epidermal keratinocytes (HaCaT). In vitro, experiments involved subjecting HaCaT cells to UVB radiation (50 mJ/cm2) for a 24 h incubation period, leading to cell death, increased reactive oxygen species (ROS), and DNA damaged lesion (8-Oxo Gunosine). ATN treatment effectively mitigated cell toxicity, ROS generation, and 8-Oxo Gunosine in UVB-exposed HaCaT cells. Furthermore, ATN demonstrated its ability to counteract UVB radiation-exposed oxidative stress by inhibiting the activation of phosphorylated-extracellular signal-regulated kinase-1 (Erk-1), phosphorylated-c-Jun N-terminal kinase (p-Jnk), and phosphorylated p38 Mitogen-Activated Protein Kinase (p-p38) in HaCaT cells. Nuclear factor erythroid 2-related factor 2 (NrF2), recognized for its antioxidant properties, emerged as a key player in protecting against oxidative damage. ATN was observed to inhibit the depletion of NrF2 expression, thereby preventing the depletion of superoxide dismutase (SOD), and glutathione (GSH) in UVB-exposed HaCaT cells. Additionally, ATN inhibited activator protein-1 (AP-1) and matrix metalloproteinases such as MMP-1 and MMP-9 in UVB-exposed HaCaT cells. In conclusion, our findings highlight that ATN effectively prevents UVB-exposed skin oxidative damage and photoaging by modulating NrF2 expression.

Transduction of jellyfish superoxide dismutase mediated by TAT peptide ameliorates H2O2-induced oxidative stress in HaCaT cells

Superoxide dismutase (SOD) plays important roles in the balance of oxidation and antioxidation in body mostly by scavenging superoxide anion free radicals (O2.-). Previously, we reported a novel Cu/Zn SOD from jellyfish Cyanea capillata, named CcSOD1, which exhibited excellent SOD activity and high stability. TAT peptide is a common type of cell penetrating peptides (CPPs) that efficiently deliver extracellular biomacromolecules into cytoplasm. In this study, we constructed a recombinant expression vector that combined the coding sequences of TAT peptide and CcSOD1, and then obtained sufficient and high-purity TAT-CcSOD1 fusion protein. Compared with some reported SODs/CPP-SODs, TAT-CcSOD1 possessed stronger tolerance to heat and acid-base environment. TAT-CcSOD1 efficiently penetrated cell membrane and significantly enhanced the O2.- scavenging ability in cells, and attenuated H2O2-induced cytotoxicity and NO generation in HaCaT cells. This study serves as a critical step forward for the application of TAT-CcSOD1 as a potential protective/therapeutic agent against oxidative stress-related conditions in the future.

Peucedanum praeruptorum Dunn leaf aqueous extract protects against alcoholic gastric injury by inhibiting inflammation and oxidative stress in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Peucedanum praeruptorum Dunn (PPD) was used to treat gastrointestinal disease in China before the Tang Dynasty, and it was considered a "Top-grade" herb in Shennong Bencaojing, known for its ability to relieve the stomach Qi and indigestion.

AIM OF THE STUDY

Alcohol consumption can induce severe gastric mucosal injury that lacks effective and safe interventions. We aimed to investigate the gastroprotective effects of Peucedanum praeruptorum Dunn leaf (PPL) after bolting in alcohol-induced gastric damage in mice.

MATERIALS AND METHODS

Mice were orally administered PPL aqueous extract at doses of 2.5, 5, and 10 g/kg for 5 consecutive days prior to the induction of gastric damage model with ethanol. Gastric tissue was stained by hematoxylin and eosin (H&E), and the levels of pro-inflammatory cytokines and oxidative stress indicators were determined using ELISA and RT-qPCR. RNA-seq was used to detect differentially expressed genes (DEGs) in the gastric tissue, while Western blotting was employed to measure the expressions of IL-17, TNF-a, and AKT pathways.

RESULTS

Treatment with PPL alleviated alcohol-induced gastric damage in mice, whereas dried root (PPD) and stem (PPS) of Peucedanum praeruptorum Dunn had no gastroprotective function. The content of peucedanocoumarin I was higher in the dried PPL compared to PPD and PPS, with an increase in peucedanocoumarin I content in PPL after boiling. Additionally, PPL administration (5, 10 g/kg) decreased pro-inflammatory factors, such as interleukin-6 (IL-6), IL-8, IL-4, IL-1β, IL-18, and tumor necrosis factor (TNF-a) in alcohol-induced gastric injury mice (p < 0.05), and improved oxidative stress markers, including superoxide dismutase enzymes (SOD), catalase (CAT), and malondialdehyde (MDA) (p < 0.05). RNA-seq data revealed that PPL treatment inhibited alcohol-induced inflammation-related signals, including IL-17 and TNF pathways, and restored alcohol-inhibited gastric digestive and metabolic functions, such as xenobiotics metabolism of cytochrome P450, and protein digestion and absorption pathways. Notably, treatment with PPL downregulated the expressions of IL-17 A, TNF-a, monocyte chemoattractant protein-1 (MCP-1), and AKT-phosphorylation induced by ethanol exposure (p < 0.05). Thus, the aqueous extract of PPL provided protection against alcohol-induced gastric injury by mitigating inflammation and oxidative stress in mice, suggesting a potential novel therapeutic approach for alcohol-induced gastric damage.

Based on network pharmacology, molecular docking and experimental verification to reveal the mechanism of Andrographis paniculata against solar dermatitis

BACKGROUND

Solar dermatitis (SD) is an acute, damaging inflammation of the skin caused by UV exposure, especially UVB. Therefore, the discovery of novel anti-SD therapeutic agents is crucial. Andrographis paniculata (AP) is a medicinal plant with a wide range of pharmacological effects. Increased evidence shows that AP has potential therapeutic effects on SD. However, the therapeutic mechanisms of AP against SD have not yet been completely elucidated, which is an unexplored field.

PURPOSE

This study employed network pharmacology, molecular docking and experimental verification to ascertain the active constituents, possible targets, and biological pathways associated with AP in the treatment of SD.

METHODS

AP-related active ingredients and their potential targets were screened from TCMSP and Swiss Target Prediction database, respectively. Potential therapeutic targets of SD were collected using the GeneCards, DrugBank and OMIM databases. Then, we established protein-protein interaction (PPI), compound-target-disease (D-C-T-D) through Cytoscape to identify the major components, core targets of AP against SD. Next, the GO and KEGG pathway was identified by the David database of AP in the treatment of SD. Molecular docking techniques were used to estimate the binding force between the components and the hub genes. In this paper, we used UVB-irradiated HaCaT keratinocytes as an in vitro model and established the dorsal skin of UVB-irradiated ICR mice as an in vivo model to explore the mechanism for further verification.

RESULTS

There were 24 active components and 63 related target genes in AP against SD. PPI analysis showed that AKT-1, TNF-α, IL6, MMP9, EGFR, and PTGS2 shared the highest centrality among all target genes. KEGG pathway analysis revealed that the PI3K-Akt signaling pathway may be central in the anti-SD system. The molecular docking results showed that the main active components of AP have strong binding affinity with hub genes. In vitro results showed that WG had a protective effect on UVB-intervened HaCat cells. Western blot analysis showed that WG intervention achieved anti-inflammation by reducing the phosphorylated expression of AKT, PI3K proteins in the PI3K-AKT signaling pathway and downregulating the expression of TNF-α, IL-6, EGFR. Furthermore, Histological analysis confirmed that administration of WG to ICR mice significantly ameliorated UVB-induced skin roughness, epidermal thickening, disturbed collagen fiber alignment and wrinkles. Meanwhile, immunohistochemistry showed that administration of WG to ICR mice significantly reduced UVB-induced expression of MMP9, MPO, F4/80 in the skin. These results provide new insights into the contribution of WG to the development of clinical treatment modalities for UVB-induced SD.

CONCLUSION

The crucial element in the fight against SD is WG, with the primary route being PI3K/Akt. The main components and hub genes had robust binding abilities. In vitro and vivo experiments showed that WG could inhibit the expression level of the hub genes by inhibiting the PI3K/Akt pathway. In summary, the information presented in this study indicates that WG might be utilised as a treatment for UVB-induced SD.

miR-3606-3p alleviates skin fibrosis by integratively suppressing the integrin/FAK, p-AKT/p-ERK, and TGF-β signaling cascades

INTRODUCTION

Fibroblast abnormalities are crucial causes of skin fibrosis, including systemic sclerosis (SSc) and keloids. However, their mechanisms, including underlying microRNA regulatory mechanisms, remain elusive.

OBJECTIVES

This study aimed to evaluate the roles, mechanisms, and therapeutic potential of miR-3606-3p in regulating multiple fibroblast abnormalities.

METHODS

The miR-3606-3p levels were evaluated in skin tissues and primary fibroblasts. RNA-seq and luciferase assays were employed to identify miR-3606-3p targets. Collagen contraction, western blotting, in vivo imaging, and real-time cellular analysis were used to assess fibroblast abnormalities. The therapeutic potential of miR-3606-3p was evaluated in mice.

RESULTS

MiR-3606-3p decreased in skin tissues (SSc: Fold Change (FC) =  - 2.95, P = 0.0101; keloid: FC =  - 3.42, P < 0.0001) and primary fibroblasts (SSc: FC =  - 12.74, P = 0.0278; keloid: FC =  - 2.08, P = 0.0021) from skin fibrosis patients, and negatively correlated with disease severity. Mechanistically, miR-3606-3p targeted the 3'-untranslated regions (3'-UTRs) of Integrin αV (ITGAV), GRB2-associated binding protein 1 (GAB1), and transforming growth factor beta receptor 2 (TGFBR2), all of these three targets increased in skin fibrosis. Simultaneously, miR-3606-3p inhibited fibroblast's fibrogenesis, migration, inflammation, and proliferation by inhibiting ITGAV/integrin/FAK, GAB1/p-AKT/p-ERK, and TGFBR2/p-SMAD2/3 signaling. ITGAV-mediated integrin/FAK signaling unidirectionally activated the p-AKT/p-ERK and p-SMAD2/3 pathways. Knockdown of GAB1 and TGFRB2 reduced ITGAV-induced p-AKT/p-ERK and p-SMAD2/3 activities. MiR-3606-3p, si-ITGAV, si-GAB1, and si-TGFBR2 exhibited significant inhibition of fibrogenesis and migration. Inflammation was primarily inhibited by si-ITGAV and si-GAB1, while proliferation was primarily inhibited by si-TGFBR2. Moreover, miR-3606-3p significantly attenuates skin fibrosis in keloid-bearing mice.

CONCLUSIONS

MiR-3606-3p is downregulated in skin fibrosis. Moreover, it negatively correlates with disease severity. Functionally, miR-3606-3p inhibits fibrogenesis, migration, inflammation, and proliferation of fibroblasts. Mechanistically, miR-3606-3p inhibits ITGAV, GAB1, and TGFBR2 by targeting their 3'-UTRs. ITGAV-, GAB1-, and TGFBR2-activated integrin/AKT/ERK/SMAD2/3 signaling induced fibroblast abnormalities. In vivo, miR-3606-3p inhibits skin fibrosis in mice. Therefore, the multi-targeting, multi-phenotypic regulatory properties of miR-3606-3p suggest its potential utility in clinical treatment.

RNAs m6A modification facilitates UVB-induced photoaging

RNA N6-methylation (m6A) modification is common in eukaryotic mRNA and has been linked to various physiological disorders, including UVB-induced photoaging. To identify biological differences among photoaging. Three pairs of normal and photoaged skin tissues were collected for m6A RNA sequencing assay. Transcriptome profiles showed differential m6A methylation modifications in 1365 mRNAs in photoaging skin tissues. Pathway analysis revealed the involvement of cellular stress response and regulation of cell cycle G2/M phase transition in m6A-mRNAs. Further experiments validated the differential expression of m6A methyltransferases (METTL3 and METTL14) and hypermethylation modification in mRNAs (CENPE, PPM1B and TPM1). In vitro studies demonstrated that increased METTL3 and METTL14 levels promoted m6A methylation of CENPE, PPM1B and TPM1 in UVB-induced photoaging cells, and further experiments on mice showed that downregulation of METTL3 and METTL14 reduced m6A modifications in CENPE, PPM1B and TPM1, leading to the delayed appearance of photoaging phenotypes, suggesting that these genes could serve as potential therapeutic targets for treating photoaging. Our study characterized key transcriptome changes in photoaging and identified the role of METTL3 and METTL14 in mediating m6A modification, resulting in the upregulation of CENPE, PPM1B and TPM1 expression, which may be crucial in UVB-induced photoaging.

Exploring mechanisms of skin aging: insights for clinical treatment

The skin is the largest organ in the human body and is made up of various cells and structures. Over time, the skin will age, which is not only influenced by internal factors, but also by external environmental factors, especially ultraviolet radiation. Aging causes immune system weakening in the elderly, which makes them more susceptible to dermatosis, such as type 2 inflammatory mediated pruritus. The immune response in this condition is marked by senescent cells consistently releasing low amounts of pro-inflammatory cytokines through a senescence-associated secretory phenotype (SASP). This continuous inflammation may accelerate immune system aging and establish a connection between immune aging and type 2 inflammatory skin diseases. In addition, two chronic pigmentation disorders, vitiligo and chloasma, are also associated with skin aging. Aged cells escape the immune system and accumulate in tissues, forming a microenvironment that promotes cancer. At the same time, "photoaging" caused by excessive exposure to ultraviolet radiation is also an important cause of skin cancer. This manuscript describes the possible links between skin aging and type 2 inflammation, chronic pigmentation disorders, and skin cancer and suggests some treatment options.

Succinylated Type I Collagen Regulates Ferroptosis to Attenuate Skin Photoaging

During the process of photoaging in the skin, Succinylated type I collagen has a significant effect on reversing the damage caused by UVB radiation, with the regulation of cellular ferroptosis being one of its important pathophysiological mechanisms. Specifically, Succinylated type I collagen reduces the expression of key cell cycle regulators P16, P21, and P53, as well as the ferroptosis-related factor Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4), induced by UVB radiation in cells and tissues. Meanwhile, it increases the expression of key factors Glutathione Peroxidase 4 (GPX4) and Solute Carrier Family 7 Member 11 (SLC7A11), which inhibit ferroptosis. Additionally, our study also reveals the impact of Succinylated type I collagen on the levels of malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS) in cells and tissues, directly affecting the cells' ability to cope with oxidative stress. This further suggests that Succinylated type I collagen may improve skin photoaging through various pathways, including regulating ferroptosis, antioxidation, promoting collagen synthesis, protecting the skin barrier, reducing pigmentation, and inhibiting inflammatory responses, contributing to maintaining healthy and youthful skin.

Bifidobacterium lactis-Derived Vesicles Attenuate Hippocampal Neuroinflammation by Targeting IL-33 to Regulate FoxO6/P53 Signaling

BACKGROUND

Hippocampal Neuroinflammation (HNF) is a critical driver of cognitive impairment. The lipopolysaccharide (LPS) accumulate amyloid beta (Aβ) and lead to HNF. The Bifidobacterium lactis (BL) 99 have anti-inflammatory ability. However, whether BL99-derived microbiota-derived vesicles (MV) could alleviate LPS-induced HNF remains unclear.

METHODS

To investigate, we used ultrafiltration with ultracentrifuge to extract BL99-derived-MV (BL99-MV). We used hippocampal neuronal HT22 cells (HT22) to establish the LPS-induced HNF model, and explored whether BL99-MV alleviate LPS-induced HNF.

RESULTS

The confocal microscopy showed that BL99-MV were taken up by HT22 and reduced the oxidative stress (ROS) level. The PCR showed that BL99-MV up-regulate IL-10 level, and down-regulate TNF-α, IL-1β, and IL-6. Transcriptomic analysis revealed 4127 differentially expressed genes, with 2549 genes upregulated and 1578 genes downregulated in the BL99-MV group compared to the LPS group. Compared to the LPS group, BL99-MV decreased FoxO6, IL-33, P53, and NFκB expression, but increased FoxO1 and Bcl2 expression. The WB showed that BL99-MV modulated NFκB, FoxO6, P53, Caspase9, and Caspase3 protein expression by reducing IL-33 expression in HT22. The findings demonstrated IL-33 as a regulator for FoxO6/P53 signaling.

CONCLUSIONS

Here, we hypothesized that BL99-MV alleviated LPS-induced HNF to promote HT22 survival and synaptic development by regulating FoxO6/P53 signaling by targeting IL-33.

Functional hyaluronic acid microneedles for skin photoaging based on collagen induction and oxidative stress regulation strategies

Photoaging holds remarkable importance for skin health and senescence. Ultraviolet (UV) irradiation results in the disruption of the extracellular matrix (ECM) microenvironment, the degradation of collagen, and the generation of oxidative stress. Traditional hyaluronic acid (HA) exhibits a diminished capacity to stimulate collagen regeneration, and hampered by its poor permeability as a macromolecule, ultimately resulting in constrained therapeutic outcomes for the treatment of photoaging. In this study, HA/PX was prepared by functional modification of HA with sulfonate-rich or phosphatidylcholine-rich polymers, which could complement the loss of ECM and ameliorate the senescence of human fibroblasts (HDFs) and hairless mouse models subjected to UVB-induced photoaging. The results indicate that HA/PX exhibits superior abilities in delaying cellular aging, promoting collagen regeneration, and resisting reactive oxygen species (ROS) compared to HA. Furthermore, HA/PX shows good biocompatibility both in vivo and in vitro, without causing allergic reactions or other adverse effects. We also demonstrated that the transdermal delivery of HA/PX via microneedle arrays (MNs) can significantly mitigate wrinkles and skin damage in photoaged nude mice, and achieve the treatment of skin photoaging by enhancing epidermal thickness, promoting collagen deposition, and reducing oxidative stress. Therefore, our research offers a novel possibility for future anti-aging therapeutic strategies.

Update on protease-activated receptor 2 in inflammatory and autoimmune dermatological diseases

Protease-activated receptor 2 (PAR2) is a cell-surface receptor expressed in various cell types, including keratinocytes, neurons, immune and inflammatory cells. Activation of PAR2, whether via its canonical or biased pathways, triggers a series of signaling cascades that mediate numerous functions. This review aims to highlight the emerging roles and interactions of PAR2 in different skin cells. It specifically summarizes the latest insights into the roles of PAR2 in skin conditions such as atopic dermatitis (AD), psoriasis, vitiligo and melasma. It also considers these roles from the perspective of the cutaneous microenvironment in relation to other inflammatory and autoimmune dermatological disorders. Additionally, the review explores PAR2's involvement in associated comorbidities from both cutaneous and extracutaneous diseases. Therefore, PAR2 may serve as a key target for interactions among various cells within the local skin environment.

Protease-Activated Receptor 2 in inflammatory skin disease: current evidence and future perspectives

Protease-activated receptor-2 (PAR2) is a class-A G protein-coupled receptor (GPCR) activated by serine proteases and is expressed by multiple tissues, including the skin. PAR2 is involved in the skin inflammatory response, promoting Th2 inflammation, delaying skin barrier repair, and affecting the differentiation of keratinocytes. It also participates in the transmission of itch and pain sensations in the skin. Increasing evidence indicates that PAR2 plays an important role in the pathogenesis of inflammatory skin diseases such as acne vulgaris, rosacea, psoriasis, and atopic dermatitis. Additional focus will be placed on potential targeted therapies based on PAR2. The Goal of this review is to outline the emerging effects of PAR2 activation in inflammatory skin disease and highlight the promise of PAR2 modulators.

L-asparaginase induces IP3R-mediated ER Ca2+ release by targeting µ-OR1 and PAR2 and kills acute lymphoblastic leukemia cells

L-asparaginase is a standard therapeutic option for acute lymphoblastic leukemia (aLL), a hematologic cancer that claims the most lives of pediatric cancer patients. Previously, we demonstrated that L-asparaginase kills aLL cells via a lethal rise in [Ca2+]i due to IP3R-mediated ER Ca2+ release followed by calpain-1-Bid-caspase-3/12 activation (Blood, 133, 2222-2232). However, upstream targets of L-asparaginase that trigger IP3R-mediated ER Ca2+ release remain elusive. Here, we show that L-asparaginase targets µ-OR1 and PAR2 and induces IP3R-mediated ER Ca2+ release in aLL cells. In doing so, µ-OR1 plays a major role while PAR2 plays a minor role. Utilizing PAR2- and µ-OR1-knockdown cells, we demonstrate that L-asparaginase stimulation of µ-OR1 and PAR2 relays its signal via Gαi and Gαq, respectively. In PAR2-knockdown cells, stimulation of adenylate cyclase with forskolin or treatment with 8-CPT-cAMP reduces L-asparaginase-induced µ-OR1-mediated ER Ca2+ release, suggesting that activation of µ-OR1 negatively regulates AC and cAMP. In addition, the PKA inhibitor 14-22 amide (myr) alone evokes ER Ca2+ release, and subsequent L-asparaginase treatment does not induce further ER Ca2+ release, indicating the involvement of PKA inhibition in L-asparaginase-induced µ-OR1-mediated ER Ca2+ release, which can bypass the L-asparaginase-µ-OR1-AC-cAMP loop. This coincides with (a) the decreases in PKA-dependent inhibitory PLCβ3 Ser1105 phosphorylation, which prompts PLCβ3 activation and ER Ca2+ release, and (b) BAD Ser118 phosphorylation, which leads to caspase activation and apoptosis. Thus, our findings offer new insights into the Ca2+-mediated mechanisms behind L-asparaginase-induced aLL cell apoptosis and suggest that PKA may be targeted for therapeutic intervention for aLL.

Synergistic delivery of hADSC-Exos and antioxidants has inhibitory effects on UVB-induced skin photoaging

Ultraviolet B (UVB) light exposure accelerates skin photoaging. Human adipose-derived stem cell exosomes (hADSC-Exos) and some antioxidants may have anti-photoaging effects. However, it is unknown whether the combination of hADSC-Exos and antioxidants plays a synergistic role in anti-photoaging. In cellular and 3D skin models, we showed that vitamin E (VE) and hADSC-Exos were optimal anti-photoaging combinations. In vivo, VE and hADSC-Exos increased skin tightening and elasticity in UVB-induced photoaging mice Combined treatment with VE and hADSC-Exos inhibited SIRT1/NF-κB pathway. These findings contribute to the understanding of hADSC-Exos in conjunction with other antioxidants, thereby providing valuable insights for the future pharmaceutical and cosmetic industries.

Salvianolic acid B protects against UVB-induced skin aging via activation of NRF2

BACKGROUND

Prolonged exposure to sun radiation may result in harmful skin photoaging. Therefore, discovering novel anti-photoaging treatment modalities is critical. An active component isolated from Salvia miltiorrhiza (SM), Salvianolic acid B (Sal-B), is a robust antioxidant and anti-inflammatory agent. This investigation aimed to discover the therapeutic impact and pathways of salvianolic acid B for UVB-induced skin photoaging, an area that remains unexplored.

METHODS

We conducted in vitro experiments on human dermal fibroblasts (HDFs) exposed to UVB radiation, assessing cellular senescence, superoxide dismutase (SOD) activity, cell viability, proliferation, migration, levels of reactive oxygen species (ROS), and mitochondrial health. The potential mechanism of Sal-B was analyzed using RNA sequencing, with further validation through Western blotting, PCR, and nuclear factor erythroid 2-related factor 2 (NRF2) silencing methods. In vivo, a model of skin photoaging induced by UVB in nude mice was employed. The collagen fiber levels were assessed utilizing hematoxylin and eosin (H&E), Masson, and Sirus red staining. Additionally, NRF2 and related gene and protein expression levels were identified utilizing PCR and Western blotting.

RESULTS

Sal-B was found to significantly counteract photoaging in UVB-exposed skin fibroblasts, reducing aging-related decline in fibroblast proliferation and an increase in apoptosis. It was observed that Sal-B aids in protecting mitochondria from excessive ROS production by promoting NRF2 nuclear translocation. NRF2 knockdown experiments established its necessity for Sal-B's anti-photoaging effects. The in vivo studies also verified Sal-B's anti-photoaging efficacy, surpassing that of tretinoin (Retino-A). These outcomes offer novel insights into the contribution of Sal-B in developing clinical treatment modalities for UVB-induced photodamage in skin fibroblasts.

CONCLUSION

In this investigation, we identified the Sal-B protective impact on the senescence of dermal fibroblasts and skin photoaging induced by radiation of UVB. The outcomes suggest Sal-B as a potential modulator of the NRF2 signaling pathway.

SerpinB3: A Multifaceted Player in Health and Disease-Review and Future Perspectives

SerpinB3, a member of the serine-protease inhibitor family, has emerged as a crucial player in various physiological and pathological processes. Initially identified as an oncogenic factor in squamous cell carcinomas, SerpinB3's intricate involvement extends from fibrosis progression and cancer to cell protection in acute oxidative stress conditions. This review explores the multifaceted roles of SerpinB3, focusing on its implications in fibrosis, metabolic syndrome, carcinogenesis and immune system impairment. Furthermore, its involvement in tissue protection from oxidative stress and wound healing underscores its potential as diagnostic and therapeutic tool. Recent studies have described the therapeutic potential of targeting SerpinB3 through its upstream regulators, offering novel strategies for cancer treatment development. Overall, this review underscores the importance of further research to fully elucidate the mechanisms of action of SerpinB3 and to exploit its therapeutic potential across various medical conditions.

Adverse outcome pathway-based approach to reveal the mechanisms of skin sensitization and long-term aging effects of chlorothalonil

Chlorothalonil (CHT) is a widely used antifungal agent and is reported to be a sensitizer that can cause allergic contact dermatitis (ACD). ACD initiation is associated with various innate immune cell contributions and is usually accompanied by persistent inflammation, which is a potential contributing factor to skin damage. However, detailed information on the mechanisms by which CHT induces skin sensitization and damage is still insufficient. This study focused on investigating the possible sensitization process and mechanism of CHT and the adverse effects of repeated CHT exposure. CHT activates dendritic cells and promotes the proliferation of lymph cells in the skin sensitization phase, causing severe inflammation. Keratinocytes activate the NLRP3 inflammasome pathway to cause inflammation during CHT treatment, and macrophages also secrete inflammatory cytokines. In addition, CHT-induced inflammation triggered skin wrinkles, decreased epidermal thickness and decreased collagen. Cell experiments also showed that repeated exposure to CHT led to cell proliferation inhibition and senescence, and CHT-induced autophagy dysfunction was not only the reason for inflammation but also for senescence. This study defined the possible process through which CHT is involved in the skin sensitization phase and elucidated the mechanism of CHT-induced inflammation in innate immune responses. We also determined that repeated CHT exposure caused persistent inflammation, ultimately leading to skin aging.

Rubus urticifolius Compounds with Antioxidant Activity, and Inhibition Potential against Tyrosinase, Melanin, Hyaluronidase, Elastase, and Collagenase

In our study, using chromatographic techniques, we isolated three bioactive compounds, which were structurally elucidated as (E)-2-(3-(3,4-dimethoxyphenyl)acrylamido)-N-methylbenzamide (1), 4-Hydroxyquinoline-2-carboxylic acid (2), and (E)-2-Cyano-3-(4-hydroxyphenyl)acrylic acid (3), using spectroscopic methods. The anti-melanogenic, anti-inflammatory, antioxidant, and anti-aging properties were evaluated in vitro by measuring the activity of pharmacological targets including tyrosinase, melanin, NF-κB, hyaluronidase, elastase, collagenase, and Nrf2. Our results show that compound 1 is the most active with IC50 values of 14.19 μM (tyrosinase inhibition), 22.24 μM (melanin inhibition), 9.82-12.72 μM (NF-κB inhibition), 79.71 μM (hyaluronidase inhibition), 80.13 μM (elastase inhibition), 76.59 μM (collagenase inhibition), and 116-385 nM (Nrf2 activation) in the THP-1, HEK001, WS1, and HMCB cells. These findings underscore the promising profiles of the aqueous extract of R. urticifolius at safe cytotoxic concentrations. Additionally, we report, for the first time, the isolation and characterisation of these nitrogenous compounds in the R. urticifolius species. Finally, compound 1, isolated from R. urticifolius, is a promising candidate for the development of more effective and safer compounds for diseases related to skin pigmentation, protection against inflammation, and oxidative stress.

UV radiation-induced peptides in frog skin confer protection against cutaneous photodamage through suppressing MAPK signaling

Overexposure to ultraviolet light (UV) has become a major dermatological problem since the intensity of ultraviolet radiation is increasing. As an adaption to outside environments, amphibians gained an excellent peptide-based defense system in their naked skin from secular evolution. Here, we first determined the adaptation and resistance of the dark-spotted frogs (Pelophylax nigromaculatus) to constant ultraviolet B (UVB) exposure. Subsequently, peptidomics of frog skin identified a series of novel peptides in response to UVB. These UV-induced frog skin peptides (UIFSPs) conferred significant protection against UVB-induced death and senescence in skin cells. Moreover, the protective effects of UIFSPs were boosted by coupling with the transcription trans-activating (TAT) protein transduction domain. In vivo, TAT-conjugated UIFSPs mitigated skin photodamage and accelerated wound healing. Transcriptomic profiling revealed that multiple pathways were modulated by TAT-conjugated UIFSPs, including small GTPase/Ras signaling and MAPK signaling. Importantly, pharmacological activation of MAPK kinases counteracted UIFSP-induced decrease in cell death after UVB exposure. Taken together, our findings provide evidence for the potential preventive and therapeutic significance of UIFSPs in UV-induced skin damage by antagonizing MAPK signaling pathways. In addition, these results suggest a practicable alternative in which potential therapeutic agents can be mined from organisms with a fascinating ability to adapt.

Impaired Mitochondrial Energy Metabolism Regulated by p70S6K: A Putative Pathological Feature in Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disease. Mitochondrial energy metabolism and p70 ribosomal protein S6 kinase (p70S6K) play significant roles in AD pathology. However, the potential relationship between them is unclear. In this study, bioinformatics methods were initially applied to analyze the transcriptomic data in the CA1 and the primary visual cortex of patients with AD and Aβ42-treated SH-SY5Y cells. By applying secreted Aβ42 and p70S6K gene silencing in cells, we explored disorders in mitochondrial function and the regulatory roles of p70S6K by flow cytometry, laser scanning confocal microscopy, high-performance liquid chromatography, Western blotting, and quantitative reverse transcription PCR. The study reveals that impaired mitochondrial energy metabolism is a potential pathological feature of AD and that p70S6K gene silencing reversed most of the changes induced by Aβ42, such as the activities of the electron transport chain complexes I and III, as well as ATP synthase, ATP production, generation of reactive oxygen species, mitochondrial membrane potential, and phosphorylation of AMPK, PINK1, and Parkin, all of which are required for mitochondria to function properly in the cell.

Olea europaea leaf exosome-like nanovesicles encapsulated in a hyaluronic acid / tannic acid hydrogel dressing with dual "defense-repair" effects for treating skin photoaging

Photoaging, primarily caused by ultraviolet (UV) light, is the major factor in extrinsic skin aging. Existing anti-photoaging strategies mainly focus on early sun protection or repairing damaged skin, lacking a comprehensive treatment strategy. Therefore, this study developed a dressing that actively shields against UV radiation and repairs photoaged skin, offering double protection. This study utilized exosome-like nanovesicles derived from Olea europaea leaves (OLELNVs), enhancing them into a potent core biomaterial with high-dose effects and skin-friendly, non-cytotoxic inhibition of cell aging. These nanovesicles were incorporated into a cross-linked hyaluronic acid (HA) and tannic acid (TA) hydrogel with strong UV-absorbing properties, creating the OLELNVs@HA/TA hydrogel system. In vitro and in vivo experiments demonstrated that OLELNVs@HA/TA hydrogel can effectively reduce UV-induced skin damage and promote skin repair and regeneration. Additionally, RNA-seq and clustering analysis of miR168a-5p predicted targets revealed significant down-regulation of the NF-κB signaling pathway, mediating inflammatory aging responses. Overall, the OLELNVs@HA/TA hydrogel represents a novel dual-strategy approach for clinical application in combating photoaging.

Macrophage migration inhibitory factor mediates skin aging via CD74: Insights from single-cell and bulk RNA sequencing data

Cell-cell communication is crucial for regulating signaling and cellular function. However, the precise cellular and molecular changes remain poorly understood in skin aging. Based on single-cell and bulk RNA data, we explored the role of cell-cell ligand-receptor interaction in skin aging. We found that the macrophage migration inhibitory factor (MIF)/CD74 ligand-receptor complex was significantly upregulatedin aged skin, showing the predominant paracrine effect of keratinocytes on fibroblasts. Enrichment analysis and in vitro experiment revealed a close association of the activation of the MIF/CD74 with inflammatory pathways and immune response. Mechanistically, MIF/CD74 could significantly inhibit PPARγ protein, which thus significantly increased the degree of fibroblast senescence, and significantly up-regulated the expression of senescence-associated secretory phenotype (SASP) factors and FOS gene. Therefore, our study reveals that MIF/CD74 inhibits the activation of the PPAR signaling pathway, subsequently inducing the production of SASP factors and the upregulation of FOS expression, ultimately accelerating fibroblast senescence.

Par2-mediated responses in inflammation and regeneration: choosing between repair and damage

The protease activated receptor 2 (Par2) plays a pivotal role in various damage models, influencing injury, proliferation, inflammation, and regeneration. Despite extensive studies, its binary roles- EITHER aggravating injury or promoting recovery-make a conclusive translational decision on its modulation strategy elusive. Analyzing two liver regeneration models, autoimmune hepatitis and direct hepatic damage, we discovered Par2's outcome depends on the injury's nature. In immune-mediated injury, Par2 exacerbates damage, while in direct tissue injury, it promotes regeneration. Subsequently, we evaluated the clinical significance of this finding by investigating Par2's expression in the context of autoimmune diabetes. We found that the absence of Par2 in all lymphocytes provided full protection against the autoimmune destruction of insulin-producing β-cells in mice, whereas the introduction of a β-cell-specific Par2 null mutation accelerated the onset of autoimmune diabetes. This pattern led us to hypothesize whether these observations are universal. A comprehensive review of recent Par2 publications across tissues and systems confirms the claim drafted above: Par2's initial activation in the immune system aggravates inflammation, hindering recovery, whereas its primary activation in the damaged tissue fosters regeneration. As a membrane-anchored receptor, Par2 emerges as an attractive drug target. Our findings highlight a crucial translational modulation strategy in regenerative medicine based on injury type.

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.

Role of umbilical cord mesenchymal stromal cells in skin rejuvenation

Aging is the main cause of many degenerative diseases. The skin is the largest and the most intuitive organ that reflects the aging of the body. Under the interaction of endogenous and exogenous factors, there are cumulative changes in the structure, function, and appearance of the skin, which are characterized by decreased synthesis of collagen and elastin, increased wrinkles, relaxation, pigmentation, and other aging characteristics. skin aging is inevitable, but it can be delayed. The successful isolation of mesenchymal stromal cells (MSC) in 1991 has greatly promoted the progress of cell therapy in human diseases. The International Society for Cellular Therapy (ISCT) points out that the MSC is a kind of pluripotent progenitor cells that have self-renewal ability (limited) in vitro and the potential for mesenchymal cell differentiation. This review mainly introduces the role of perinatal umbilical cord-derived MSC(UC-MSC) in the field of skin rejuvenation. An in-depth and systematic understanding of the mechanism of UC-MSCs against skin aging is of great significance for the early realization of the clinical transformation of UC-MSCs. This paper summarized the characteristics of skin aging and summarized the mechanism of UC-MSCs in skin rejuvenation reported in recent years. In order to provide a reference for further research of UC-MSCs to delay skin aging.

METTL14 affects UVB-induced human dermal fibroblasts photoaging via miR-100-3p biogenesis in an m6A-dependent manner

Exposure to ultraviolet radiation can lead to skin photoaging, which increases the risk of skin tumors. This study aims to investigate how microRNA m6A modification contributes to skin photoaging. This study found that skin fibroblasts exposed to a single UVB dose of 30 mJ/cm2 exhibited characteristics of photoaging. The m6A level of total RNA decreased in photoaged cells with a down-regulated level of METTL14, and overexpression of METTL14 displayed a photoprotective function. Moreover, miR-100-3p was a downstream target of METTL14. And METTL14 could affect pri-miR-100 processing to mature miR-100-3p in an m6A-dependent manner via DGCR8. Furthermore, miR-100-3p targeted at 3' end untranslated region of ERRFI1 mRNA with an inhibitory effect on translation. Additionally, photoprotective effects of overexpression of METTL14 were reversed by miR-100-3p inhibitor or overexpression of ERRFI1. In UVB-induced photoaging of human skin fibroblasts, METTL14-dependent m6A can regulate miR-100-3p maturation via DGCR8 and affect skin fibroblasts photoaging through miR-100-3p/ERRFI1 axis.

Ferulic acid in synergy with retinol alleviates oxidative injury of HaCaT cells during UVB-induced photoaging

Application of retinol (Vitamin A, VA) in skincare is limited for instability, poor water solubility, and skin intolerance that combats skin aging. We employed computer-aided virtual screening and cell experiments with transcriptomics, thereby unveiling the comprehensive gene expression and regulation pathway of photoaging HaCaT cell treated with ferulic acid (FA) in synergizing with VA. Through network pharmacology analysis, the combined use of VA and FA exhibited highly correlated cross-targets with skin aging acting on EGFR, PTPN1, ESR2, GSK3B, BACE1, PYGL, PTGS2 and APP. The indicators of oxidative stress, such as SOD, GSH, MDA, CAT and ROS in HaCaT cells after co-administration, were significantly improved from those in photoaging group (p<0.0001). 155 differential expressed genes (DEGs) were specific between groups, while reducing the expression of PTGS2 was identified as an important regulatory factor in photoaging HaCaT cells by VA and FA. Those DEGs of co-administration group focused on oxidative-reduction enzyme activity, skin growth, keratinization, and steroid biosynthesis. Apparently, the co-administration of VA and FA effectively mitigated the process of UVB-induced photoaging by reducing oxidative stress injury, inflammation responses, and regulating cell growth. This synergistic approach significantly slowed down the photoaging progression and improved the applied performance of VA in HaCaT cells.

Preventive and Therapeutic Benefits of Natural Ingredients in Photo-Induced Epidermal Dysfunction

BACKGROUND

The skin, particularly the epidermis, is subjected to various external stresses, including ultraviolet (UV) irradiation. UV irradiation, mainly UVB at wavelength of 280-315 nm, can alter several epidermal functions, including cutaneous inflammation, epidermal hyperproliferation, DNA damage, disruption of epidermal permeability barrier and reduction in stratum corneum hydration levels. Because of the negative impacts of UVB irradiation on epidermal functions, great efforts have been made to develop regimens for the protection of alterations in epidermal function induced by UV irradiation.

SUMMARY

While sunscreen can provide physical barrier to UV light, some natural ingredients can also effectively protect the skin from UVB irradiation-induced damages. Studies have demonstrated that either topical or oral administrations of some natural ingredients attenuate UVB irradiation-induced alterations in the epidermal function. The underlying mechanisms by which natural ingredients improve epidermal functions are attributable to antioxidation, stimulation of keratinocyte differentiation, increases in the content of epidermal natural moisturizers and inhibition of inflammation.

KEY MESSAGE

Some natural ingredients exhibit protective and therapeutical benefits in photo-induced epidermal dysfunctions via divergent mechanisms.

Comprehensive transcriptional analysis of early dorsal skin development in pigs

Porcine skin is similar to human skin in physiology, anatomy and histology and is often used as a model animal for human skin research. There are few studies on the transcriptome aspects of pig skin during the embryonic period. In this study, RNA sequencing was performed on the dorsal skin of Chenghua sows at embryonic day 56 (E56), embryonic day 76 (E76), embryonic day 105 (E105), and 3 days after birth (D3) to explore RNA changes in pig dorsal skin at four ages. A number of skin-related differential genes were identified by intercomparison between RNAs at four time points, and KEGG functional analysis showed that these differential genes were mainly enriched in metabolic and developmental, immune, and disease pathways, and the pathways enriched in GO analysis were highly overlapping. Collagen is an important part of the skin, with type I collagen making up the largest portion. In this study, collagen type I alpha 1 (COL1A1) and collagen type I alpha 2 (COL1A2) were significantly upregulated at four time points. In addition, lncRNA-miRNA-mRNA and miRNA-circRNA coexpression networks were constructed. The data obtained may help to explain age-related changes in transcriptional patterns during skin development and provide further references for understanding human skin development at the molecular level.

The roles of gut microbiome and metabolites associated with skin photoaging in mice by intestinal flora sequencing and metabolomics

Photoaging of skin, a chronic disease, can produce the appearance changes and cancer lesions of skin. Therefore, it is of great significance to investigate the mechanisms and explore effective methods to treat the disorder. Gut microbiota and intestinal metabolisms have critical roles in a variety of diseases. However, their roles on photoaging of skin were not well tested. In the present work, the results showed that compared with control group, the levels of MDA, SOD and CAT associated with oxidative stress, the levels of COL I, CER, and HA associated with skin function, and the mRNA levels of IL-1β, IL-6, TNF-α associated with inflammation after long-term exposure to ultraviolet radiation in mice were significantly changed. Skin pathological tissue was also seriously damaged. The protein levels of AQP3 and FLG were significantly decreased. Ultraviolet exposure also promoted skin photoaging by activating TNFR1/TRAF2-mediated MAPK pathway, in which the protein levels of P38/P-P38, c-FOS/P-c-FOS, MMP1, TNFR1 and TRAF2 were significantly increased in model mice compared with control group. In fecal microbiota transplantation (FMT) experiment, we found that the intestinal microbiome of control mice alleviated skin photoaging via adjusting the protein levels of P38/P-P38, c-FOS/P-c-FOS, MMP1, TNFR1 and TRAF2. 16S rRNA sequencing found that 1639 intestinal bacteria were found, in which 15 bacteria including norank_f_Ruminococcaceae, Lachnospirac -eae_NK4A136_group, Lachnoclostridium, etc., were significantly different at the genus level. Untargeted GC-TOF/MS and UHPLC-MS/MS metabolomics showed 72 and 188 metabolites including taurine, ornithine, L-arginine, L-histidine, sucrose with significant differences compared with control group. Then, amino acid targeting assay showed 10 amino acids including L-ornithine, L-arginine and L-citrulline with higher levels in control group compared with model group. In addition, we also found that the variation of Lachnoclostridium abundance may regulate L-arginine metabolism to affect skin photoaging. Some intestinal bacteria and metabolites including amino acids may be closely related to skin photoaging, which should provide new methods to treat skin photoaging in the future.

The proteolytic activity in inflammatory bowel disease: insight from gut microbiota

Inflammatory bowel disease (IBD) is a chronic, recurrent inflammatory disease caused by the destruction of the intestinal mucosal epithelium that affects a growing number of people worldwide. Although the etiology of IBD is complex and still elucidated, the role of dysbiosis and dysregulated proteolysis is well recognized. Various studies observed altered composition and diversity of gut microbiota, as well as increased proteolytic activity (PA) in serum, plasma, colonic mucosa, and fecal supernatant of IBD compared to healthy individuals. The imbalance of intestinal microecology and intestinal protein hydrolysis were gradually considered to be closely related to IBD. Notably, the pivotal role of intestinal microbiota in maintaining proteolytic balance received increasing attention. In summary, we have speculated a mesmerizing story, regarding the hidden role of PA and microbiota-derived PA hidden in IBD. Most importantly, we provided the diagnosis and therapeutic targets for IBD as well as the formulation of new treatment strategies for other digestive diseases and protease-related diseases.