Skin fibrosis is primarily characterized by excessive fibroblasts proliferation and aberrant extracellular matrix accumulation, leading to pathological conditions such as hypertrophic scars, keloids, and systemic sclerosis. This dynamic and complex process involves intricate interactions among various resident skin cells and inflammatory cells, ultimately resulting in extracellular matrix deposition and even invasive growth. The maintenance of cellular phenotypes and functions relies on dynamic metabolic responses, and cellular signal transduction is closely coupled with metabolic processes. Given that the coupling of cell metabolism and signaling in the skin fibrosis microenvironment plays a critical role in inflammatory responses and fibrotic activation, modulation of these metabolic pathways may offer novel therapeutic strategies for inhibiting or even reversing the progression of skin fibrosis. This review systematically summarizes the metabolic characteristics of various cell types involved in skin fibrosis, with a focus on core metabolic reprogramming mechanisms such as hyperactive glycolysis, dysregulated fatty acid metabolism, cellular metabolic dysfunction and dysregulated mTOR/AMPK signaling. Furthermore, potential intervention strategies targeting these metabolic pathways are explored, thereby providing new research perspectives for the treatment of skin fibrosis.
Humans ; Fibrosis/metabolism* ; Skin/metabolism* ; Signal Transduction ; Fibroblasts/pathology* ; TOR Serine-Threonine Kinases/metabolism* ; Skin Diseases/pathology* ; Cellular Reprogramming ; Metabolic Reprogramming

Currently, research on N⁶-methyladenine (m⁶A) is extensive in the field of oncology, while studies involving m⁶A and skin diseases remain relatively limited. Based on existing reports, we searched PubMed and Web of Science for literature related to m⁶A and dermatological conditions. Analysis of citation counts and journal impact factors revealed a significant upward trend in the volume of m⁶A-related research. Term frequency analysis of titles and abstracts indicated that studies mainly focus on skin tumors and inflammatory or immune-related skin diseases, particularly melanoma, psoriasis, and skin development. Transcriptomic data from the Gene Expression Omnibus (GEO) were analyzed, revealing differential expression of m⁶A-related genes in 4 types of skin tumors (including squamous cell carcinoma and basal cell carcinoma) as well as in inflammatory skin diseases such as psoriasis and atopic dermatitis, and potential mechanisms of action were also explored. Findings suggest that m⁶A modifications exhibit heterogeneity between neoplastic and non-neoplastic skin diseases. However, the regulatory mechanisms of m⁶A dynamic modifications on key genes involved in dermatological disorders remain unclear and warrant further investigation.
Humans ; Skin Neoplasms/metabolism* ; Skin Diseases/metabolism* ; Adenosine/genetics* ; Psoriasis/genetics* ; Carcinoma, Squamous Cell/genetics* ; Carcinoma, Basal Cell/genetics* ; Melanoma/genetics*

OBJECTIVE: To determine the role of Tripterygium wilfordii multiglycoside (TGW) in the treatment of psoriatic dermatitis from a cellular immunological perspective. METHODS: Mouse models of psoriatic dermatitis were established by imiquimod (IMQ). Twelve male BALB/c mice were assigned to IMQ or IMQ₊TGW groups according to a random number table. Histopathological changes in vivo were assessed by hematoxylin and eosin staining. Ratios of immune cells and cytokines in mice, as well as PAM212 cell proliferation in vitro were assessed by flow cytometry. Pro-inflammatory cytokine expression was determined using reverse transcription quantitative polymerase chain reaction. RESULTS: TGW significantly ameliorated the severity of IMQ-induced psoriasis-like mouse skin lesions and restrained the activation of CD45⁺ cells, neutrophils and T lymphocytes (all P<0.01). Moreover, TGW significantly attenuated keratinocytes (KCs) proliferation and downregulated the mRNA levels of inflammatory cytokines including interleukin (IL)-17A, IL-23, tumor necrosis factor α, and chemokine (C-X-C motif) ligand 1 (P<0.01 or P<0.05). Furthermore, it reduced the number of γ δ T17 cells in skin lesion of mice and draining lymph nodes (P<0.01). CONCLUSIONS TGW improved psoriasis-like inflammation by inhibiting KCs proliferation, as well as the associated immune cells and cytokine expression. It inhibited IL-17 secretion from γ δ T cells, which improved the immune-inflammatory microenvironment of psoriasis.
Male ; Animals ; Mice ; Tripterygium ; Psoriasis/drug therapy* ; Keratinocytes ; Skin Diseases/metabolism* ; Cytokines/metabolism* ; Imiquimod/metabolism* ; Dermatitis/pathology* ; Disease Models, Animal ; Mice, Inbred BALB C ; Skin/metabolism*

Objective: To explore the effect of deep dermal tissue dislocation injury on skin fibrosis in pig, in order to provide some theoretical basis for burn scar treatment. Methods: The experimental research method was applied. Six 2-month-old female Duroc pigs were taken. Fifteen operative areas on the right dorsum of pigs on which medium-thick skin grafts and deep dermal tissue slices were cut and re-implanted were included into dermal in situ reimplantation group, and fifteen operative areas on the left dorsum of pigs on which medium-thick skin grafts and deep dermal tissue slices were cut and the deep dermal tissue slice was placed under the fat layer were included into the dermal dislocation group. The hair growth in the operative areas on post-injury day (PID) 7, 14, and 21 and the cross-sectional structure on PID 14 were observed in the two groups. On PID 7, 14, and 21, the skin thickness (the distance from the epidermis to the upper edge of the fat), the dermal thickness (the distance from the lower edge of the epidermis to the upper edge of the fat, excluding the fibrotic tissue thickness between the dermis and the fat), and the fibrosis tissue thickness of the dermis-fat interface (from the lower edge of the deep dermis to the upper edge of the fat in dermal in situ reimplantation group and from the lower edge of the superficial dermis to the upper edge of the fat in dermal dislocation group) in the operative areas were measured and compared between the two groups; the fibrotic tissue thickness at the dermal cutting interface (from the lower edge of the superficial dermis to the upper edge of the deep dermis) in the operative areas in dermal in situ reimplantation group was measured and compared with the fibrotic tissue thickness at the dermal-fat interface. Sirius red staining was performed to observe and compare the type Ⅰ and Ⅲ collagen content in the dermal-fat interface in the operative areas between the 2 groups and between the dermal cutting interface and dermal-fat interface in the operative areas in dermal in situ reimplantation group. Immunohistochemical staining was performed to observe the positive expressions of proliferating cell nuclear antigen (PCNA), transforming growth factor β₁ (TGF-β₁), fibroblast growth factor 2 (FGF-2), and hepatocyte growth factor (HGF) in the operative areas in the two groups. The sample number was 6. Data were statistically analyzed with independent sample t test. Results: On PID 7, 14, and 21, the hairs in the operative areas in dermal in situ reimplantation group were denser than those in dermal dislocation group. On PID 14, the skin cross section in the operative areas in dermal dislocation group showed a "sandwich"-like structure, while the skin cross section in the operative areas in dermal in situ reimplantation group had normal structure. On PID 7, 14, and 21, the skin thickness in the operative areas in dermal dislocation group was (4 234±186), (4 688±360), and (4 548±360) μm, respectively, which was close to (4 425±156), (4 714±141), and (4 310±473) μm in dermal in situ reimplantation group (P>0.05); the dermal thickness in the operative areas in dermal dislocation group was significantly thinner than that in dermal in situ reimplantation group (with t values of -9.73, -15.85, and -15.41, respectively, P<0.01); the fibrotic tissue thickness at the dermal-fat interface in the operative areas in dermal dislocation group was significantly thicker than that in dermal in situ reimplantation group (with t values of 14.48, 20.58, and 15.67, respectively, P<0.01); there was no statistically significant difference between the fibrotic tissue thickness at the dermal-fat interface and the dermal cutting interface in the operative areas in dermal in situ reimplantation group (P>0.05). On PID 7, 14, 21, the type Ⅲ collagen content in the dermal-fat interface in the operative areas in dermal dislocation group was increased significantly compared with that in dermal in situ replantation group (with t values of 2.65, 0.61, and 7.39, respectively, P<0.05 or P<0.01), whereas there were no statistically significant differences in the type Ⅰ collagen content at the dermal-fat interface in the operative areas between the 2 groups (P>0.05) and the type Ⅰ and Ⅲ collagen content between the dermal-fat interface and the dermal cutting interface in the operative areas in dermal in situ reimplantation group (P>0.05). On PID 7, 14, and 21, PCNA, TGF-β₁, FGF-2, and HGF were positively expressed in the superficial dermis and adipose tissue in the operative areas in dermal dislocation group, while PCNA, TGF-β₁, FGF-2, and HGF were positively expressed in the superficial dermis, deep dermis, and adipose tissue in the operative areas in dermal in situ reimplantation group. Conclusions: Inadequate intrinsic thickness of dermal tissue is the key factor causing fibrosis, and the biological purpose of fibrosis is to "compensate" the intrinsic thickness of the skin. Besides, adipose tissue may also be an important component of fibrotic skin repair.
Swine ; Female ; Animals ; Dermis/pathology* ; Proliferating Cell Nuclear Antigen/metabolism* ; Fibroblast Growth Factor 2 ; Cross-Sectional Studies ; Fibrosis ; Skin Diseases/pathology* ; Collagen/metabolism*

BACKGROUND: Green tobacco sickness (GTS), an occupational disease in tobacco harvesters, is a form of acute nicotine intoxication by nicotine absorption through the skin from the wet green tobacco plant. We carried out a questionnaire survey and measured cotinine concentration, the metabolic product of nicotine, to determine the prevalence, incidence, and risk factors of GTS in Korean tobacco harvesters. METHODS: We measured cotinine concentrations, and administered a questionnaire survey to tobacco harvesters in Cheongsong-gun, Gyeongsangbuk-do, Korea. We repeatedly measured urine cotinine concentration five times with a questionnaire survey. RESULTS: Cotinine concentration at dawn was significantly higher than that at other times; it was significantly lower during the nonharvesting period than during the harvesting period. However, little change in cotinine concentration was detected in the daytime during the harvesting period. Study participants included 20 men and 20 women. The prevalence of GTS was 37.5% and was significantly higher in women than in men (55.0% vs. 20.0%, p < 0.01). GTS incidence according to number of workdays was 3.4 occurrences/100 person days. CONCLUSION: In this study, nicotine exposure and metabolism were experimentally determined from the time of cotinine exposure, and biological monitoring was performed in each season. In the future, this information may be valuable for medical decision-making in GTS prevention.
Absorption ; Clinical Decision-Making ; Cotinine ; Environmental Monitoring ; Farmers ; Female ; Gyeongsangbuk-do ; Humans ; Incidence ; Korea ; Male ; Metabolism ; Nicotine ; Occupational Diseases ; Plants ; Prevalence ; Risk Factors ; Seasons ; Skin ; Tobacco*

BACKGROUNDStevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening diseases with high mortality rates. This study was designed to analyze the pathogenic factors, clinical manifestations, complications, treatment, and prognosis of SJS/TEN and to explore the differences between surviving and deceased patients.

METHODSSJS/TEN patients admitted to Beijing Friendship Hospital from January 2006 to December 2015 were included in the study. Patients' data were retrospectively analyzed. Comparative studies were performed on the survival group and the deceased group, and Fisher's exact probability test was used for statistical analysis.

RESULTSAmong the 88 patients included, 40 (45.5%) were male with a mean age of 45 ± 18 years. Forty-eight (54.5%) had SJS, 34 (38.6%) had SJS/TEN, and 6 (6.8%) had TEN. Fifty-three (60.2%) cases were caused by medications, mainly antibiotics (n = 24) followed by traditional Chinese medicines (n = 7). Forty-two cases (47.7%) developed visceral damage. Eighty-two patients improved or recovered and were discharged from hospital, and six patients died. Comparative studies on the survival group and the deceased group showed that the presence of malignant tumor ( χ2 = 27.969,P < 0.001), connective tissue diseases ( χ2 = 9.187, P= 0.002), previous abnormal liver/kidney functions ( χ2 = 6.006, P= 0.014), heart rate >100 times/min ( χ2 = 6.347, P= 0.012), detached skin area >20% ( χ2 = 5.594, P= 0.018), concurrent mucosal involvement at the mouth, eyes, and external genitals ( χ2 = 4.945, P= 0.026), subsequent accompanying liver/kidney damage ( χ2 = 11.839, P= 0.001, and χ2 = 36.302,P < 0.001, respectively), and SCORTEN score >2 ( χ2 = 37.148,P < 0.001) increased the risk of death.

CONCLUSIONSSJS/TEN is mainly caused by medications, and nearly half of patients develop visceral damage. Multiple factors increase the mortality risk.

Adult ; Anti-Bacterial Agents ; therapeutic use ; Connective Tissue Diseases ; metabolism ; pathology ; Eye ; pathology ; Female ; Genitalia ; pathology ; Humans ; Kidney ; metabolism ; pathology ; Liver ; metabolism ; pathology ; Male ; Middle Aged ; Mouth ; pathology ; Retrospective Studies ; Skin ; metabolism ; pathology ; Stevens-Johnson Syndrome ; drug therapy ; metabolism ; pathology

Psoriasis is a common inflammatory skin disease with complex etiology and chronic progression. To provide novel insights into the regulatory molecular mechanisms of the disease, we performed RNA sequencing analysis of 14 pairs of skin samples collected from patients with psoriasis. Subsequent pathway analysis and extraction of the transcriptional regulators governing psoriasis-associated pathways was executed using a combination of the MetaCore Interactome enrichment tool and the cisExpress algorithm, followed by comparison to a set of previously described psoriasis response elements. A comparative approach allowed us to identify 42 core transcriptional regulators of the disease associated with inflammation (NFκB, IRF9, JUN, FOS, SRF), the activity of T cells in psoriatic lesions (STAT6, FOXP3, NFATC2, GATA3, TCF7, RUNX1), the hyperproliferation and migration of keratinocytes (JUN, FOS, NFIB, TFAP2A, TFAP2C) and lipid metabolism (TFAP2, RARA, VDR). In addition to the core regulators, we identified 38 transcription factors previously not associated with the disease that can clarify the pathogenesis of psoriasis. To illustrate these findings, we analyzed the regulatory role of one of the identified transcription factors (TFs), FOXA1. Using ChIP-seq and RNA-seq data, we concluded that the atypical expression of the FOXA1 TF is an important player in the disease as it inhibits the maturation of naive T cells into the (CD4+FOXA1+CD47+CD69+PD-L1(hi)FOXP3−) regulatory T cell subpopulation, therefore contributing to the development of psoriatic skin lesions.
Humans ; Inflammation ; Keratinocytes ; Lipid Metabolism ; Psoriasis* ; Response Elements ; Sequence Analysis, RNA ; Skin ; Skin Diseases ; T-Lymphocytes ; Transcription Factors

Stromal cells provide a crucial microenvironment for overlying epithelium. Here we investigated the expression and function of a stromal cell-specific protein, stromal cell-derived factor-1 (SDF-1), in normal human skin and in the tissues of diseased skin. Immunohistology and laser capture microdissection (LCM)-coupled quantitative real-time RT-PCR revealed that SDF-1 is constitutively and predominantly expressed in dermal stromal cells in normal human skin in vivo. To our surprise, an extremely high level of SDF-1 transcription was observed in the dermis of normal human skin in vivo, evidenced by much higher mRNA expression level than type I collagen, the most abundant and highly expressed protein in human skin. SDF-1 was also upregulated in the tissues of many human skin disorders including psoriasis, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Double immunostaining for SDF-1 and HSP47 (heat shock protein 47), a marker of fibroblasts, revealed that fibroblasts were the major source of stroma-cell-derived SDF-1 in both normal and diseased skin. Functionally, SDF-1 activates the ERK (extracellular-signal-regulated kinases) pathway and functions as a mitogen to stimulate epidermal keratinocyte proliferation. Both overexpression of SDF-1 in dermal fibroblasts and treatment with rhSDF-1 to the skin equivalent cultures significantly increased the number of keratinocyte layers and epidermal thickness. Conversely, the stimulative function of SDF-1 on keratinocyte proliferation was nearly completely eliminated by interfering with CXCR4, a specific receptor of SDF-1, or by knock-down of SDF-1 in fibroblasts. Our data reveal that extremely high levels of SDF-1 provide a crucial microenvironment for epidermal keratinocyte proliferation in both physiologic and pathologic skin conditions.
Adult ; Cell Proliferation ; Chemokine CXCL12 ; genetics ; Epidermal Cells ; Epidermis ; pathology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Fibroblasts ; metabolism ; Gene Expression Regulation ; Humans ; Keratinocytes ; cytology ; pathology ; Signal Transduction ; Skin Diseases ; genetics ; pathology

Chronic urticaria (CU) is a common allergic skin disease that requires long-term pharmacological treatment. Some patients with severe CU suffer a poor quality of life. Although the pathogenic mechanisms of CU are not clearly understood, several groups have suggested that genetic mechanisms are involved in various CU cohorts. To further understand the molecular genetic mechanisms of CU, we summarize recent genetic data in this review. Although a few HLA alleles were suggested to be candidate markers in different ethnic groups, further replication studies that apply the recent classification are needed. Genetic polymorphisms in histamine-related genes, including FcepsilonRI and HNMT, were suggested to be involved in mast cell activation and histamine metabolism. Several genetic polymorphisms of leukotriene-related genes, such as ALOX5, LTC4S, and the PGE2 receptor gene PTGER4, were suggested to be involved in leukotriene overproduction, a pathogenic mechanism. Further investigations using candidate gene approaches and genome-wide association studies (GWAS) will provide new insights into the molecular genetic mechanisms of CU, which will provide new marker genes for differentiation of CU phenotypes and identification of potential therapeutic targets.
Alleles ; Classification ; Cohort Studies ; Dinoprostone ; Ethnic Groups ; Genome-Wide Association Study ; Histamine ; Humans ; Leukotriene C4 ; Mast Cells ; Metabolism ; Molecular Biology* ; Phenotype ; Polymorphism, Genetic ; Quality of Life ; Skin Diseases ; Urticaria*

BACKGROUNDGlycoprotein non-metastatic melanoma protein B (GPNMB) plays an important role in the pathogenesis of inflammatory and malignant diseases. We investigated the expression of GPNMB in benign and malignant skin diseases.

METHODSTissue microarray was performed in the skin tissues of 102 cases including malignant melanoma (MM), squamous cell carcinoma (SCC), basal cell carcinoma (BCC), and benign dermatosis. The expression of GPNMB in the tissues was detected by immunohistochemistry. Twenty cases of normal skin and adjacent neoplastic normal skin tissues were selected as controls.

RESULTSGPNMB was positively stained in skin malignancies (38/50, 76%), which was significantly higher than that in the control and the benign skin tissues (P = 0.001 and < 0.001 respectively). GPNMB was positively stained in MM (13/15, 87%) and SCC (16/20, 80%) (P < 0.001). Significant higher expression of GPNMB was observed in patients aged ≥ 65 years than those less than 65 years (n = 11 and n = 9 respectively, P = 0.027). No significant difference of the expression rates was observed between normal control and BCC; however, stronger intensity was detected in the latter. Negative or weak expression was observed in the controls.

CONCLUSIONOver-expression of GPNMB correlated strongly and might play an important role in the pathogenesis of MM and SCC.

Adolescent ; Adult ; Aged ; Carcinoma, Basal Cell ; metabolism ; Carcinoma, Squamous Cell ; metabolism ; Female ; Humans ; Immunohistochemistry ; Male ; Melanoma ; metabolism ; Membrane Glycoproteins ; metabolism ; Middle Aged ; Skin ; metabolism ; pathology ; Skin Diseases ; metabolism ; Skin Neoplasms ; metabolism ; Tissue Array Analysis ; methods ; Young Adult