Validation of neuron-specific enolase in cardiac arrest patients with limited withdrawal of life-sustaining therapy.

Aim: We validated the prognostic performance of neuron-specific enolase (NSE) according to the recommended values in cardiac arrest (CA) survivors. Methods: We analyzed the data of adult CA survivors who underwent targeted temperature management between January 2014 and December 2020. We measured the NSE level 48 h and 72 h after CA. We performed receiver operating characteristics (ROC) and used the reference value (17 µg/L) and the guidelines-suggested value (60 µg/L) as thresholds. The primary outcome was 6-month neurological outcomes with Cerebral Performance Category (CPC), dichotomized into good (CPC 1 or 2) or poor (CPC 3-5). Results: Of the 513 included patients, 346 (67.4 %) patients had poor neurological outcomes. The area under ROC (AUC) of NSE at 48 h was 0.887 (95 % confidence intervals [CIs], 0.851-0.909) with the Youden index of 35.6 µg/L. A false positive rate (FPR) of <2 % was observed (54.1 µg/L). The thresholds values (17, 60) had a sensitivity of 86.1% and 56.7 % and a specificity of 66.7%and 98.8 %, respectively. The AUC of NSE at 72 h was 0.892 (95 % CIs, 0.849-0.920) with the Youden index of 30.4 µg/L. The threshold values (17, 60) had a sensitivity of 86.0%and 59.4 % with a specificity of 72.2%and 98.3 %, respectively. An FPR of <2 % was observed (53.6 µg/L). Among the 156 patients and 113 patients with NSE at 48 h and at 72 h ≤ 17 µg/L, respectively, 109 and 83 patients had good neurological outcomes. Conclusions: The cut-off value of NSE (60 µg/L) was acceptable to predict poor neurological outcomes with an FPR <2 % in cardiac arrest survivors, irrespective of at 48 or 72 h. NSE (17 µg/L) can function as mitigating factor to deter early WLST.

Acute kidney injury as a prognostic predictor of in-hospital mortality and neurological outcomes in patients after extracorporeal cardiopulmonary resuscitation.

INTRODUCTION: Extracorporeal cardiopulmonary resuscitation (ECPR) is increasingly being applied to patients with refractory cardiac arrest, but the survival rate to hospital discharge is only approximately 29%. Because ECPR requires intensive resources, it is important to predict outcomes. We therefore investigated the prognostic association between acute kidney injury (AKI) and ECPR to confirm the performance of AKI as a prognostic predictor of in-hospital mortality and neurological outcomes in ECPR. METHODS: We conducted a retrospective observational study on patients undergoing ECPR for cardiac etiology at Chonnam National University Hospital from 2015 to 2021. The group diagnosed with AKI in any KDIGO category within the first 48 h after ECPR was compared to that without AKI, and the primary outcome of the study was in-hospital mortality. RESULTS: Of 138 enrolled patients, 83 were studied. Hospital mortality occurred in 49 patients (59%), and 55 (66.3%) showed poor neurological outcomes. The AKI group displayed significantly elevated in-hospital mortality (77.8% vs 24.1%) and poor neurological outcomes (81.5% vs 37.9%) compared to the non-AKI group (p < 0.001). Regression analysis showed that AKI was associated with significantly higher rates of both in-hospital mortality (odds ratio (OR) range 10.75-12.88) and neurologic outcomes (OR range 5.9-6.22). CONCLUSIONS: There was a significant association of AKI with both in-hospital mortality and poor neurologic outcome in patients after ECPR, and AKI can be used as an early prognostic predictor in these patients.

Adiponectin prevents skin inflammation in rosacea by suppressing S6 phosphorylation in keratinocytes.

Numerous recent evidence highlights epidemiological connections between rosacea and metabolic disorders. However, the precise path through which metabolic factors impact rosacea risk is still unclear. Therefore, this study aims to investigate the role of adiponectin, a crucial adipokine that regulates metabolic homeostasis, in the pathogenesis of rosacea. We elucidated a detrimental feedback loop between rosacea-like skin inflammation and decreased levels of skin adiponectin. To elaborate, rosacea lesional skin exhibits diminished adiponectin expression compared to non-lesional areas in the same patients. Induction of rosacea-like inflammation reduced adiponectin levels in the skin by generating inflammatory cytokines that suppress adiponectin production from subcutaneous adipocytes. Conversely, complete depletion of adiponectin exacerbated rosacea-like features in the mouse model. Mechanistically, adiponectin deficiency led to heightened S6 phosphorylation, a marker of the mTORC1 signaling pathway, in the epidermis. Adiponectin significantly inhibited S6 phosphorylation in cultured keratinocytes. Notably, replenishing adiponectin whole protein or topically applying an agonist for adiponectin receptor 1 successfully improved rosacea-like features in mice. This study contributes to understanding the role of adiponectin in skin inflammation associated with rosacea pathophysiology, suggesting that restoring adiponectin function in the skin could be a potential therapeutic strategy.

Systemic Inflammatory Proteomic Biomarkers in Atopic Dermatitis: Exploring Potential Indicators for Disease Severity.

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory cutaneous disorder, that emerges from intricate interplays among genetic predisposition, immune dysregulation, environmental factors, and compromised skin barrier. Understanding the inflammatory pathway in AD is important due to its fundamental role in the pathogenesis of AD. This study aimed to explore the diverse spectrum of proteins linked to the inflammation of AD and the relationship between systemic biomarkers and clinical severity in AD. METHODS: We examined the blood samples from 48 patients with AD and 48 healthy controls (HCs) using the Proximity Extension Assay (Olink). Differentially expressed proteins (DEPs) were identified and Pearson correlation analysis was conducted to determine systemic proteomic biomarkers associated with severity of AD. RESULTS: A total of 29 DEPs were significantly up-regulated and 2 DEPs were significantly down-regulated in AD compared with the HC. The MCP-4, IL-18, MCP-3, TNFRSF9, and IL-17C were the top 5 highest DEPs associated with the severity of AD. CONCLUSION: Our study sheds light on the intricate network of inflammatory proteins in AD and their potential implications for disease severity. Our results indicate that these systemic inflammatory proteins could be valuable for assessing AD severity and enhancing our understanding of the disease's complexity and its potential management strategies.

Mortality in sea lions is associated with the introduction of the H5N1 clade 2.3.4.4b virus in Brazil October 2023: whole genome sequencing and phylogenetic analysis.

Clade 2.3.4.4b highly pathogenic avian influenza (HPAI) H5N1 virus was detected in the South American sea lions found dead in Santa Catarina, Brazil, in October 2023. Whole genome sequencing and comparative phylogenetic analysis were conducted to investigate the origin, genetic diversity, and zoonotic potentials of the H5N1 viruses. The H5N1 viruses belonged to the genotype B3.2 of clade 2.3.4.4b H5N1 virus, which was identified in North America and disseminated to South America. They have acquired new amino acid substitutions related to mammalian host affinity. Our study provides insights into the genetic landscape of HPAI H5N1 viruses in Brazil, highlighting the continuous evolutionary processes contributing to their possible adaptation to mammalian hosts.

The Relationship between the Ratio of Urine Osmolality to Serum Osmolality and Neurological Outcomes in Out-of-hospital Cardiac Arrest Patients.

Background: Progressive ischemic brain injury after cardiac arrest can cause damage to the hypothalamic-pituitary axis, particularly the pituitary gland. This may impact serum osmolality (SOsm) and urine osmolality (UOsm) in patients who have experienced out-of-hospital cardiac arrest (OHCA). We assumed that a low ratio of UOsm to SOsm (USR) is related to poor outcomes among OHCA patients. Therefore, the present study was designed to evaluate the association between the USR within 72 h after the restoration of spontaneous circulation (ROSC) and 6-month neurological outcomes in OHCA patients. Methods: This prospective, observational study included OHCA patients with targeted temperature management at Chonnam National University Hospital in Gwangju, Korea, between January 2016 and December 2022. We collected SOsm and UOsm data at admission (T0) and 24 (T1), 48 (T2), and 72 h (T3) after ROSC. The primary outcome was a poor neurological outcome at 6 months defined by cerebral performance categories 3, 4, or 5. Results: This study included 319 patients. The mean UOsm and USRs at T0, T1, T2, and T3 of patients with poor outcomes were lower than those of patients with good outcomes. Multivariable analysis indicated that the USRs at T1 (odds ratio [OR], 0.363; 95% confidence interval [CI], 0.221-0.594), T2 (OR, 0.451; 95% CI, 0.268-0.761), and T3 (OR, 0.559; 95% CI, 0.357-0.875) were associated with a poor outcome. The areas under the receiver operating characteristic curves of USRs at T0, T1, T2, and T3 for predicting poor outcomes were 0.615 (95% CI, 0.559-0.669), 0.711 (95% CI, 0.658-0.760), 0.724 (95% CI, 0.671-0.772), and 0.751 (95% CI, 0.699-0.797), respectively. Conclusions: The USRs within 72 h of ROSC were associated with poor neurological outcomes at 6 months in OHCA patients.

The Association between Troponin-I Clearance after the Return of Spontaneous Circulation and Outcomes in Out-of-Hospital Cardiac Arrest Patients.

Background: Elevated levels of troponin-I (TnI) are common in out-of-hospital cardiac arrest (OHCA) patients. However, studies evaluating the prognostic value of TnI clearance in OHCA patients are lacking. We aimed to examine how TnI clearance (TnI-C) differed according to the neurological outcome group and mortality group at 6 months. Methods: This retrospective observational study involved adults ( ≥ 18 years) who were treated for an OHCA between January 2019 and December 2022. The TnI-Cs were calculated for days 1 to 2 (TnI-C1st) and 2 to 3 (TnI-C2nd) after the return of spontaneous circulation (ROSC). The primary outcome was a poor neurological outcome at 6 months, defined by cerebral performance categories 3, 4, and 5. The secondary outcome was 6-month mortality. Results: A total of 227 patients were included. A poor neurological outcome and mortality at 6-months were reported in 150 (66.1%) and 118 (52.0%) patients, respectively. The TnI-C1st was significantly lower in patients with a poor outcome compared with good outcome patients (neurological outcome at 6 months, 54.4% vs. 42.3%; 6-month mortality, 52.1% vs. 42.7%, respectively). In the multivariable analyses, a TnI-C1st < 50% was associated with a poor neurological outcome (odds ratio [OR] 2.078, 95% confidence interval [CI] 1.080-3.995, p = 0.028) and mortality (OR 2.131, 95% CI 1.114-4.078, p = 0.022) at 6 months. Conclusions: After ROSC, TnI-C1st < 50% was associated with a poor neurological outcome and mortality at 6 months in OHCA patients.

Retraction Notice to: Decreased Lung Tumor Development in SwAPP Mice through the Downregulation of CHI3L1 and STAT 3 Activity via the Upregulation of miRNA342-3p.

[This retracts the article DOI: 10.1016/j.omtn.2019.02.007.].

Impact of fucosyltransferase 1-mediated epidermal blood group antigen H on anti-inflammatory response in atopic dermatitis.

The presence of the blood group H2 antigen on the membrane of red blood cells determines blood type O in individuals and this H2 antigen serves as a precursor to the A and B antigens expressed in blood types A and B, respectively. However, the specific involvement of ABH antigens in skin diseases is unknown. Therefore, we aim to investigate the expression of ABH antigens in skin tissue of patients with atopic dermatitis (AD) and MC903-induced AD-like mice. We demonstrated that the expression of ABH antigen is primarily located in the granular and horny layers of the skin in healthy control individuals. However, in patients with AD, the expression of the ABH antigen was absent or diminished in these layers, while the H2 antigen expression increased in the spinous layers of the affected skin lesions. Then, we investigated the biological function of blood group H antigen mediated by fucosyltransferase 1 (Fut1) in the skin, utilizing an AD mouse model induced by MC903 in wild-type (WT) and Fut1-knockout mice. After the application of MC903, Fut1-deficient mice, with no H2 antigen expression on their skin, exhibited more severe clinical signs, increased ear swelling, and elevated serum IgE levels compared with those of WT mice. Additionally, the MC903-induced thickening of both the epidermis and dermis was more pronounced in Fut1-deficient mice than that in WT mice. Furthermore, Fut1-deficient mice showed a significantly higher production of interleukin-4 (IL-4) and IL-6 in skin lesions compared with that of their WT counterparts. The expression of chemokines, particularly Ccl2 and Ccl8, was notably higher in Fut1-deficient mice compared with those of WT mice. The infiltration of CD4+ T cells, eosinophils, and mast cells into the lesional skin was significantly elevated in Fut1-deficient mice compared with that in WT mice. These findings demonstrate the protective role of H2 antigen expression against AD-like inflammation and highlight its potential therapeutic impact on AD through the regulation of blood group antigens.

Phase 1/2 trials of human bone marrow-derived clonal mesenchymal stem cells for treatment of adults with moderate to severe atopic dermatitis.

BACKGROUND: Mesenchymal stem cells (MSCs) play important roles in therapeutic applications by regulating immune responses. OBJECTIVE: We investigated the safety and efficacy of allogenic human bone marrow-derived clonal MSCs (hcMSCs) in subjects with moderate to severe atopic dermatitis (AD). METHODS: The study included a phase 1 open-label trial followed by a phase 2 randomized, double-blind, placebo-controlled trial that involved 72 subjects with moderate to severe AD. RESULTS: In phase 1, intravenous administration of hcMSCs at 2 doses (1 × 106 and 5 × 105 cells/kg) was safe and well tolerated in 20 subjects. Because there was no difference between the 2 dosage groups (P = .9), it was decided to administer low-dose hcMSCs only for phase 2. In phase 2, subjects receiving 3 weekly intravenous infusions of hcMSCs at 5 × 105 cells/kg showed a higher proportion of an Eczema Area and Severity Index (EASI)-50 response at week 12 compared to the placebo group (P = .038). The differences between groups in the Dermatology Life Quality Index and pruritus numeric rating scale scores were not statistically significant. Most adverse events were mild or moderate and resolved by the end of the study period. CONCLUSIONS: The hcMSC treatment resulted in a significantly higher rate of EASI-50 at 12 weeks compared to the control group in subjects with moderate to severe AD. The safety profile of hcMSC treatment was acceptable. Further larger-scale studies are necessary to confirm these preliminary findings.

Neuronal Cell Differentiation of iPSCs for the Clinical Treatment of Neurological Diseases.

Current chemical treatments for cerebrovascular disease and neurological disorders have limited efficacy in tissue repair and functional restoration. Induced pluripotent stem cells (iPSCs) present a promising avenue in regenerative medicine for addressing neurological conditions. iPSCs, which are capable of reprogramming adult cells to regain pluripotency, offer the potential for patient-specific, personalized therapies. The modulation of molecular mechanisms through specific growth factor inhibition and signaling pathways can direct iPSCs' differentiation into neural stem cells (NSCs). These include employing bone morphogenetic protein-4 (BMP-4), transforming growth factor-beta (TGFß), and Sma-and Mad-related protein (SMAD) signaling. iPSC-derived NSCs can subsequently differentiate into various neuron types, each performing distinct functions. Cell transplantation underscores the potential of iPSC-derived NSCs to treat neurodegenerative diseases such as Parkinson's disease and points to future research directions for optimizing differentiation protocols and enhancing clinical applications.

Virus-like particles expressing microneme-associated antigen of Plasmodium berghei confer better protection than those expressing apical membrane antigen 1.

Malaria is a global disease affecting a large portion of the world's population. Although vaccines have recently become available, their efficacies are suboptimal. We generated virus-like particles (VLPs) that expressed either apical membrane antigen 1 (AMA1) or microneme-associated antigen (MIC) of Plasmodium berghei and compared their efficacy in BALB/c mice. We found that immune sera acquired from AMA1 VLP- or MIC VLP-immunized mice specifically interacted with the antigen of choice and the whole P. berghei lysate antigen, indicating that the antibodies were highly parasite-specific. Both VLP vaccines significantly enhanced germinal center B cell frequencies in the inguinal lymph nodes of mice compared with the control, but only the mice that received MIC VLPs showed significantly enhanced CD4+ T cell responses in the blood following P. berghei challenge infection. AMA1 and MIC VLPs significantly suppressed TNF-α and interleukin-10 production but had a negligible effect on interferon-γ. Both VLPs prevented excessive parasitemia buildup in immunized mice, although parasite burden reduction induced by MIC VLPs was slightly more effective than that induced by AMA1. Both VLPs were equally effective at preventing body weight loss. Our findings demonstrated that the MIC VLP was an effective inducer of protection against murine experimental malaria and should be the focus of further development.

Whole genome sequencing of low pathogenicity avian influenza virus (H6N2) detected from a Brazilian teal (Amazonnetta brasiliensis) in Brazil, 2023.

The whole genome sequence of a low pathogenicity avian influenza virus (H6N2) was sequenced from a Brazilian teal (Amazonetta brasiliensis) in Brazil, 2023. Phylogenetic analysis of the whole genome revealed a distinct genome pertaining to South American LPAIV from 2014 to 2016, indicating extensive circulation among South American wild birds.

Chronic ultraviolet irradiation induces memory deficits via dysregulation of the dopamine pathway.

The effects of ultraviolet (UV) radiation on brain function have previously been investigated; however, the specific neurotransmitter-mediated mechanisms responsible for UV radiation-induced neurobehavioral changes remain elusive. In this study, we aimed to explore the mechanisms underlying UV radiation-induced neurobehavioral changes. In a mouse model, we observed that UV irradiation of the skin induces deficits in hippocampal memory, synaptic plasticity, and adult neurogenesis, as well as increased dopamine levels in the skin, adrenal glands, and brain. Chronic UV exposure altered the expression of genes involved in dopaminergic neuron differentiation. Furthermore, chronic peripheral dopamine treatments resulted in memory deficits. Systemic administration of a dopamine D1/D5 receptor antagonist reversed changes in memory, synaptic plasticity, adult neurogenesis, and gene expression in UV-irradiated mice. Our findings provide converging evidence that chronic UV exposure alters dopamine levels in the central nervous system and peripheral organs, including the skin, which may underlie the observed neurobehavioral shifts, such as hippocampal memory deficits and impaired neurogenesis. This study underscores the importance of protection from UV exposure and introduces the potential of pharmacological approaches targeting dopamine receptors to counteract the adverse neurological impacts of UV exposure.

Mapping the immune cell landscape of severe atopic dermatitis by single-cell RNA-seq.

BACKGROUND: Efforts to profile atopic dermatitis (AD) tissues have intensified, yet comprehensive analysis of systemic immune landscapes in severe AD remains crucial. METHODS: Employing single-cell RNA sequencing, we analyzed over 300,000 peripheral blood mononuclear cells from 12 severe AD patients (Eczema area and severity index (EASI) > 21) and six healthy controls. RESULTS: Results revealed significant immune cell shifts in AD patients, including increased Th2 cell abundance, reduced NK cell clusters with compromised cytotoxicity, and correlated Type 2 innate lymphoid cell proportions with disease severity. Moreover, unique monocyte clusters reflecting activated innate immunity emerged in very severe AD (EASI > 30). While overall dendritic cells (DCs) counts decreased, a distinct Th2-priming subset termed "Th2_DC" correlated strongly with disease severity, validated across skin tissue data, and flow cytometry with additional independent severe AD samples. Beyond the recognized role of Th2 adaptive immunity, our findings highlight significant innate immune cell alterations in severe AD, implicating their roles in disease pathogenesis and therapeutic potentials. CONCLUSION: Apart from the widely recognized role of Th2 adaptive immunity in AD pathogenesis, alterations in innate immune cells and impaired cytotoxic cells have also been observed in severe AD. The impact of these alterations on disease pathogenesis and the effectiveness of potential therapeutic targets requires further investigation.

Identifying competing endogenous RNA regulatory networks and hub genes in alcoholic liver disease for early diagnosis and potential therapeutic target insights.

Alcoholic liver disease (ALD) has a complex pathogenesis. Although early-stage ALD can be reversed by ceasing alcohol consumption, early symptoms are difficult to detect, and several factors contribute to making alcohol difficult to quit. Continued alcohol abuse worsens the condition, meaning it may gradually progress into alcoholic hepatitis and cirrhosis, ultimately, resulting in irreversible consequences. Therefore, effective treatments are urgently needed for early-stage ALD. Current research mainly focuses on preventing the progression of alcoholic fatty liver to alcoholic hepatitis and cirrhosis. However, challenges remain in identifying key therapeutic targets and understanding the molecular mechanisms that underlie the treatment of alcoholic hepatitis and cirrhosis, such as the limited discovery of effective therapeutic targets and treatments. Here, we downloaded ALD microarray data from Gene Expression Omnibus and used bioinformatics to compare and identify the hub genes involved in the progression of alcoholic fatty liver to alcoholic hepatitis and cirrhosis. We also predicted target miRNAs and long non-coding RNAs (lncRNAs) to elucidate the regulatory mechanisms (the mRNA-miRNA-lncRNA axis) underlying this progression, thereby building a competitive endogenous RNA (ceRNA) mechanism for lncRNA, miRNA, and mRNA. This study provides a theoretical basis for the early treatment of alcoholic hepatitis and cirrhosis and identifies potential therapeutic targets.

Hispidin Increases Cell Apoptosis and Ferroptosis in Prostate Cancer Cells Through Phosphatidylinositol-3-Kinase and Mitogen-activated Protein Kinase Signaling Pathway.

BACKGROUND/AIM: Chemotherapy is mainly used in the clinical treatment of prostate cancer. Different anticancer mechanisms can induce cell death in various cancers. Reactive oxygen species (ROS) play crucial roles in cell proliferation, differentiation, apoptosis, and signal transduction. It is widely accepted that ROS accumulation is closely related to chemical drug-induced cancer cell death. MATERIALS AND METHODS: We utilized the MTT assay to detect changes in cell proliferation. Additionally, colony formation and wound healing assay were conducted to investigate the effect of hispidin on cell colony formation and migration ability. Fluorescence microscopy was used to detect intracellular and mitochondrial ROS levels, while western blot was used for detection of cell apoptosis. RESULTS: Hispidin treatment significantly decreased viability of PC3 and DU145 cancer cells but exhibited no cytotoxicity in WPMY-1 cells. Furthermore, hispidin treatment inhibited cell migration and colony formation and triggered cellular and mitochondrial ROS accumulation, leading to mitochondrial dysfunction and mitochondrion-dependent apoptosis. Moreover, hispidin treatment induced ferroptosis in PC3 cells. Scavenging of ROS with N-acetyl cysteine significantly inhibited hispidin-induced apoptosis by altering the expression of apoptosis-related proteins, such as cleaved caspase-3, 9, Bax, and Bcl2. Furthermore, hispidin treatment dramatically up-regulated MAPK (involving p38, ERK, and JNK proteins) and NF-kB signaling pathways while down-regulating AKT phosphorylation. Hispidin treatment also inhibited ferroptosis signaling pathways (involving P53, Nrf-2, and HO-1 proteins) in PC3 cells. In addition, inhibiting these signaling pathways via treatment with specific inhibitors significantly reversed hispidin-induced apoptosis, cellular ROS levels, mitochondrial dysfunction, and ferroptosis. CONCLUSION: Hispidin may represent a potential candidate for treating prostate cancer.

The protective roles of integrin α4ß7 and Amphiregulin-expressing innate lymphoid cells in lupus nephritis.

Type 2 innate lymphoid cells (ILC2s) have emerged as key regulators of the immune response in renal inflammatory diseases such as lupus nephritis. However, the mechanisms underlying ILC2 adhesion and migration in the kidney remain poorly understood. Here, we revealed the critical role of integrin α4ß7 in mediating renal ILC2 adhesion and function. We found that integrin α4ß7 enables the retention of ILC2s in the kidney by binding to VCAM-1, E-cadherin, or fibronectin on structural cells. Moreover, integrin α4ß7 knockdown reduced the production of the reparative cytokine amphiregulin (Areg) by ILC2s. In lupus nephritis, TLR7/9 signaling within the kidney microenvironment downregulates integrin α4ß7 expression, leading to decreased Areg production and promoting the egress of ILC2s. Notably, IL-33 treatment upregulated integrin α4ß7 and Areg expression in ILC2s, thereby enhancing survival and reducing inflammation in lupus nephritis. Together, these findings highlight the potential of targeting ILC2 adhesion as a therapeutic strategy for autoimmune kidney diseases.

UV Irradiation Increases Appetite and Prevents Body Weight Gain through the Upregulation of Norepinephrine in Mice.

UV irradiation of the human skin downregulates lipid synthesis and adipokine production in subcutaneous fat. Recent evidence has suggested that UV exposure limits body weight gain in mouse models of obesity. However, the relationship between norepinephrine and UV irradiation has not been previously reported. Chronic UV exposure stimulated food intake but prevented body weight gain. Leptin, an appetite-suppressing hormone, was significantly reduced in the serum of the UV-irradiated mice. In contrast, UV irradiation induced browning of subcutaneous white adipose tissues without increasing physical activity. Notably, UV irradiation significantly increased norepinephrine levels, and the inhibition of norepinephrine production reversed the effects of chronic UV irradiation on food intake and body weight gain. In conclusion, chronic UV irradiation induces norepinephrine release, resulting in the stimulation of food intake due to the downregulation of leptin levels, but it prevents weight gain by inducing the browning process and elevating energy expenditure.