Dietary prenylated flavonoid xanthohumol alleviates oxidative damage and accelerates diabetic wound healing via Nrf2 activation.

Diabetic skin ulcer is one of the most common complications in patients suffering diabetes mellitus. Xanthohumol (XN), a hop-derived prenylated dietary flavonoid, has multiple health beneficial bioactivities. In the present study, we reported XN alleviates oxidative damage and accelerates diabetic wound healing via Nrf2 activation. In vitro, XN attenuated hydrogen peroxide (H2O2)-induced cytotoxicity, ROS production, cell apoptosis, as well as high glucose-induced cell damage. Mechanistic studies further demonstrated that XN could stabilize nuclear factor erythroid 2-related factor 2 (Nrf2) and promote its nuclear translocation, which was associated with AMPKα activation and covalent modification of Keap1 by XN. In vivo, XN increased Nrf2 expression and accelerated diabetic wound healing. Our study revealed a novel function of XN in diabetic wound healing as well as the underlying molecular mechanisms, suggesting XN is a promising lead compound and a potential food and/or drug candidate for the treatment of diabetic skin ulcers.

Loss of miR-1469 expression mediates melanoma cell migration and invasion.

Tumor ulceration is considered one of the most prognostically significant findings in primary cutaneous melanoma, associated with decreased disease-free and overall survival. However, the unique features associated with ulcerated melanoma that contribute to a poor prognosis in affected patients remain poorly defined. microRNAs are small, non-coding RNAs that function to inhibit expression of specific gene targets, therefore altering the functions of cells in which they are expressed. miR-1469 is a novel miR with significantly decreased expression in ulcerated melanoma tissue relative to non-ulcerated tumors. We hypothesized that loss of miR-1469 expression in melanoma contributes to altered tumor cell functions mediating disease progression. Transfection of a miR-1469 mimic resulted in a significant reduction in the migratory and invasive capacity of the CHL1 and MEL39 melanoma cell lines (>58.1% reduction, p < 0.0332), as well as the invasive capacity of the A375 melanoma cell line (>50% reduction, p < 0.0021). Expression of myeloid cell leukemia-1 (MCL1), a miR-1469 target gene, was reduced in the A375 and MEL39 cell lines by immunoblot. No significant differences in viability, resistance to apoptotic stimuli, or proliferation were observed following transfection. These findings together demonstrate how migration and invasion are specific functions through which miR-1469 expression in melanoma cells can contribute to the differences in disease progression associated with tumor ulceration.

NLRP3 protects mice from radiation-induced colon and skin damage via attenuating cGAS-STING signaling.

In the present study, the effects of NLRP3 on radiation-induced tissue damage, including colon and skin damage in mice, and the possible mechanisms were explored in vivo and in vitro. The mice were subjected to whole abdomen radiation by timed exposure to X-ray at a cumulative dose of 14 Gy. The survival rate showed that NLRP3 deficiency increased the mortality rate in mice. Furthermore, colon damage, evaluated by H&E staining and barrier function analysis, were significantly aggravated by NLRP3 deficiency. Enhanced phosphorylation of p-TBK1 and p-IRF3 in colonic tissue as well as elevated IFN-ß levels in the serum indicated hyperactivation of cGAS-STING signaling. Moreover, radiation-induced expression of p-TBK1, p-IRF3, and IFN-ß in BMDMs increased in vitro after NLRP3 knockout. Thus, our study outcomes suggest that NLRP3 may protect mice from radiation-induced tissue damage via attenuating cGAS-STING signaling.

BET bromodomain inhibitors regulate keratinocyte plasticity.

Although most acute skin wounds heal rapidly, non-healing skin ulcers represent an increasing and substantial unmet medical need that urgently requires effective therapeutics. Keratinocytes resurface wounds to re-establish the epidermal barrier by transitioning to an activated, migratory state, but this ability is lost in dysfunctional chronic wounds. Small-molecule regulators of keratinocyte plasticity with the potential to reverse keratinocyte malfunction in situ could offer a novel therapeutic approach in skin wound healing. Utilizing high-throughput phenotypic screening of primary keratinocytes, we identify such small molecules, including bromodomain and extra-terminal domain (BET) protein family inhibitors (BETi). BETi induce a sustained activated, migratory state in keratinocytes in vitro, increase activation markers in human epidermis ex vivo and enhance skin wound healing in vivo. Our findings suggest potential clinical utility of BETi in promoting keratinocyte re-epithelialization of skin wounds. Importantly, this novel property of BETi is exclusively observed after transient low-dose exposure, revealing new potential for this compound class.

A Novel RELA Truncating Mutation in a Familial Behçet's Disease-like Mucocutaneous Ulcerative Condition.

OBJECTIVE: Monogenic Behçet's disease (BD)-like conditions are increasingly recognized and to date have been found to predominantly involve loss-of-function variants in TNFAIP3. This study was undertaken to identify genetic and pathobiologic mechanisms associated with a BD-like mucocutaneous ulcerative syndrome and neuromyelitis optica (NMO) occurring in 3 generations of an Irish family (n = 5 cases and 5 familial controls). METHODS: Whole-exome sequencing was used to identify potential pathogenic variants in affected family members and determine segregation between affected and unaffected individuals. Relative v-rel reticuloendotheliosis viral oncogene homolog A (RELA) expression in peripheral blood mononuclear cells was compared by Western blotting. Human epithelial and RelA-/- mouse fibroblast experimental systems were used to determine the molecular impact of the RELA truncation in response to tumor necrosis factor (TNF). NF-κB signaling, transcriptional activation, apoptosis, and cytokine production were compared between wild-type and truncated RELA in experimental systems and patient samples. RESULTS: A heterozygous cytosine deletion at position c.1459 in RELA was detected in affected family members. This mutation resulted in a frameshift p.His487ThrfsTer7, producing a truncated protein disrupting 2 transactivation domains. The truncated RELA protein lacks a full transactivation domain. The RELA protein variants were expressed at equal levels in peripheral mononuclear cells. RelA-/- mouse embryonic fibroblasts (MEFs) expressing recombinant human RELAp.His487ThrfsTer7 were compared to those expressing wild-type RELA; however, there was no difference in RELA nuclear translocation. In RelA-/- MEFs, expression of RELAp.His487ThrfsTer7 resulted in a 1.98-fold higher ratio of cleaved caspase 3 to caspase 3 induced by TNF compared to wild-type RELA (P = 0.036). CONCLUSION: Our data indicate that RELA loss-of-function mutations cause BD-like autoinflammation and NMO via impaired NF-κB signaling and increased apoptosis.

Functional Analysis of Estrogen Receptor 1 in Diabetic Wound Healing: A Knockdown Cell-Based and Bioinformatic Study.

BACKGROUND Diabetic wound (DW) treatment is a serious challenge for clinicians, and the underlying mechanisms of DWs remain elusive. We sought to identify the critical genes in the development of DWs and provide potential targets for DW therapies. MATERIAL AND METHODS Datasets of GSE38396 from the Gene Expression Omnibus (GEO) database were reviewed. Pathway analysis was performed using the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology term analyses were carried out, and Cytoscape software (Cytoscape 3.7.2) was used to construct the protein interaction network. Serum samples from patients with diabetes and control participants were collected, and the expression of estrogen receptor 1 (ESR1) was measured by quantitative reverse-transcription polymerase chain reaction. In addition, the function of ESR1 in human skin fibroblasts was investigated in vitro. RESULTS Eight samples were analyzed using the Morpheus online tool, which identified 637 upregulated and 448 downregulated differentially expressed genes. The top 5 KEGG pathways of upregulated differentially expressed genes were associated with sphingolipid metabolism, estrogen signaling, ECM-receptor interaction, MAPK signaling, and PI3K-Akt signaling. The hub genes for DWs were JUN, ESR1, CD44, SMARCA4, MMP2, BMP4, GSK3B, WDR5, PTK2, and PTGS2. JUN, MMP2, and ESR1 were the upregulated hub genes, and ESR1 was found to be consistently enriched in DW patients. Inhibition of ESR1 had a stimulative role in human skin fibroblasts. CONCLUSIONS ESR1 was identified as a crucial gene in the development of DWs, which suggests potential therapeutic targets for DW healing.

Behçet disease (BD) and BD-like clinical phenotypes: NF-κB pathway in mucosal ulcerating diseases.

Behçet's disease (BD) is a heterogeneous multi-organ disorder in search of a unified pathophysiological theory and classification. The disease frequently has overlapping features resembling other disease clusters, such as vasculitides, spondyloarthritides and thrombophilias with similar genetic risk variants, namely HLA-B*51, ERAP1, IL-10, IL-23R. Many of the BD manifestations, such as unprovoked recurrent episodes of inflammation and increased expression of IL-1, IL-6 and TNFα, overlap with those of the hereditary monogenic autoinflammatory syndromes, positioning BD at the crossroads between autoimmune and autoinflammatory syndromes. BD-like disease associates with various inborn errors of immunity, including familial Mediterranean fever, conditions related to dysregulated NF-κB activation (eg TNFAIP3, NFKB1, OTULIN, RELA, IKBKG) and either constitutional trisomy 8 or acquired trisomy 8 in myelodysplastic syndromes. We review here the recent advances in the immunopathology of BD, BD-like diseases and the NF-κB pathway suggesting new elements in the elusive BD etiopathogenesis.

Staphylococcus aureus Fatty Acid Kinase FakA Modulates Pathogenesis during Skin Infection via Proteases.

Staphylococcus aureus fatty acid kinase FakA is necessary for the incorporation of exogenous fatty acids into the lipid membrane. We previously demonstrated that the inactivation of fakA leads to decreased α-hemolysin (Hla) production but increased expression of the proteases SspAB and aureolysin in vitro, and that the ΔfakA mutant causes larger lesions than the wild type (WT) during murine skin infection. As expected, necrosis is Hla dependent in the presence or absence of FakA, as both hla and hla ΔfakA mutants are unable to cause necrosis of the skin. At day 4 postinfection, while the ΔfakA mutant maintains larger and more necrotic abscesses, bacterial numbers are similar to those of the WT, indicating the enhanced tissue damage of mice infected with the ΔfakA mutant is not due to an increase in bacterial burden. At this early stage of infection, skin infected with the ΔfakA mutant has decreased levels of proinflammatory cytokines, such as interleukin-17A (IL-17A) and IL-1α, compared to those of WT-infected skin. At a later stage of infection (day 7), abscess resolution and bacterial clearance are hindered in ΔfakA mutant-infected mice. The paradoxical findings of decreased Hla in vitro but increased necrosis in vivo led us to investigate the role of the proteases regulated by FakA. Utilizing Δaur and ΔsspAB mutants in both the WT and fakA mutant backgrounds, we found that the absence of these proteases in a fakA mutant reduced dermonecrosis to levels similar to those of the WT strain. These studies suggest that the overproduction of proteases is one factor contributing to the enhanced pathogenesis of the ΔfakA mutant during skin infection.

Clinicopathological analysis of 34 Japanese patients with EBV-positive mucocutaneous ulcer.

Epstein-Barr virus (EBV)-positive mucocutaneous ulcer (EBVMCU) is a unifocal mucosal or cutaneous ulcer that is histologically characterized by proliferating EBV-positive atypical B cells. While EBVMCU demonstrates a histology similar to that of EBV-positive diffuse large B-cell lymphoma (DLBCL), their clinical behavior differs. Thus, characterizing distinguishing features of EBVMCU and EBV-positive DLBCL is critical. To identify unique characteristics between EBVMCU and lymphoma, we analyzed the clinicopathological and genetic features of 34 Japanese patients with EBVMCU and compared them to those of 24 EBV-positive DLBCL patients and 25 EBV-negative DLBCL patients. All patients with EBVMCU had localized ulcerative lesions, and 31 patients (91%) were using immunosuppressants, such as methotrexate (MTX) or hydroxycarbamide. All patients that were followed up with exhibited good prognosis following immunosuppressant reduction or chemotherapy. In addition, 17 EBV-positive DLBCL patients, and 15 EBV-negative DLBCL patients, received chemotherapy (P < 0.001, P < 0.001, respectively). Our data showed that EBVMCU did not increase indicators associated with lymphoma prognosis, such as soluble interleukin 2 receptor (sIL-2R) and lactate dehydrogenase (LDH) compared to those in the EBV-positive DLBCL or EBV-negative DLBCL groups (sIL-2R, P < 0.001, P = 0.025; LDH, P = 0.018, P = 0.038, respectively). However, histologically, EBVMCU exhibited EBV-positive, variable-sized, atypical B-cell proliferation. Thus, EBVMCU was histologically classified as: (1) polymorphous; (2) large cell-rich; (3) classic Hodgkin lymphoma-like; and (4) mucosa-associated lymphoid tissue lymphoma-like. Moreover, genetic analysis showed that immunoglobin heavy chain (IGH) gene rearrangement did not differ significantly between EBVMCU and EBV-positive DLBCL (44% vs. 32%; P = 0.377), or between EBVMCU and EBV-negative DLBCL (44% vs. 58%; P = 0.280). Therefore, it is difficult to distinguish EBVMCU from EBV-positive DLBCL using only pathological and genetic findings, suggesting that clinical information is important in accurately distinguishing between EBVMCU and EBV-positive DLBCL.

Is a de novo nonsense variant in the ASPDH gene the cause of ulcerative skin lesions in a Holstein calf?

BACKGROUND: Genetic skin diseases in cattle are rare. CLINICAL SUMMARY: A 7-week-old female Holstein calf was presented with epidermal lesions and alopecia in the caudal region of the ears and on the neck, as well as deep bilateral ulcerative lesions on the palmar aspect of the metacarpi and dorsal aspect of the right metacarpus. Clinical, pathological and histopathological examination of the calf was suggestive of a subepidermal vesicular dermatosis. Genetic analysis identified a de novo non-sense variant affecting the aspartate dehydrogenase domain containing (ASPDH) gene, which might be associated with the formation of subepidermal vesicles in this case. CONCLUSION AND CLINICAL IMPORTANCE: The observed phenotype in the calf may represent a novel form of a vesicular skin disorder. Haploinsufficiency of the ASPDH gene might be considered as a possible cause.

Transcriptomic Analysis of a Diabetic Skin-Humanized Mouse Model Dissects Molecular Pathways Underlying the Delayed Wound Healing Response.

Defective healing leading to cutaneous ulcer formation is one of the most feared complications of diabetes due to its consequences on patients' quality of life and on the healthcare system. A more in-depth analysis of the underlying molecular pathophysiology is required to develop effective healing-promoting therapies for those patients. Major architectural and functional differences with human epidermis limit extrapolation of results coming from rodents and other small mammal-healing models. Therefore, the search for reliable humanized models has become mandatory. Previously, we developed a diabetes-induced delayed humanized wound healing model that faithfully recapitulated the major histological features of such skin repair-deficient condition. Herein, we present the results of a transcriptomic and functional enrichment analysis followed by a mechanistic analysis performed in such humanized wound healing model. The deregulation of genes implicated in functions such as angiogenesis, apoptosis, and inflammatory signaling processes were evidenced, confirming published data in diabetic patients that in fact might also underlie some of the histological features previously reported in the delayed skin-humanized healing model. Altogether, these molecular findings support the utility of such preclinical model as a valuable tool to gain insight into the molecular basis of the delayed diabetic healing with potential impact in the translational medicine field.

Baricitinib experience on STING-associated vasculopathy with onset in infancy: A representative case from Turkey.

Stimulator of interferon genes associated vasculopathy with onset in infancy (SAVI), caused by heterozygote gain-of-function mutations in TMEM173, is characterized by fever attacks with ulcerating cutaneous manifestations on cold-sensitive areas and interstitial lung disease. A six-month-old boy was admitted to our hospital with fever, cough, and rash on the external surface of both upper and lower extremities. Respiratory symptoms consistent with ILD developed and skin lesions evolved to eschar formation particularly on acral regions. Ultimately, diagnosis of SAVI was confirmed at the age of 10 months due to the high level of interferon-score and a heterozygous N154S mutation in TMEM173. Since systemic corticosteroid and ruxolitinib were not effective, baricitinib was initiated at the age of 15 months, resulting in alleviation of fever attacks, cutaneous manifestations and respiratory symptoms within 2 months. In conclusion, we reported an infant diagnosed with SAVI at the age of 10 months and treated with baricitinib.

[Clinical research on the expression of three vascular regulatory factors in different morphological regions of Marjolin ulcer and their relationship with angiogenesis].

Objective: To investigate the expressions of vascular endothelial growth factor (VEGF), hypoxia inducible factor-1 alpha (HIF-1α), and epidermal growth factor receptor (EGFR) in different morphological regions of Marjolin ulcer and their clinical relationship with angiogenesis. Methods: From January 2012 to December 2017, the patients admitted to our hospital who met the inclusion criteria were selected, including 92 patients with Marjolin ulcer [56 males and 36 females, aged (55±15) years], 100 patients with chronic non-cancerous skin ulcer [59 males and 41 females, aged (51±16) years], and 100 patients performed with other skin-related surgery [58 males and 42 females, aged (52±15) years], and they were enrolled into Marjolin ulcer group (MU), chronic non-cancerous ulcer group (CNU), and other skin surgery group (OSS) respectively. The etiology, pathogenic site, ulcer diameter, and course of patients in group MU were retrospectively analyzed. Ulcer tissue specimens from patients of group MU and group CNU and specimens of normal skin tissue attached to the tissue resected during operation from patients of group OSS were collected. The expressions of VEGF, HIF-1α, EGFR, and CD34 in the above-mentioned tissue and the surrounding normal skin, ulcer, epitheliomatous hyperplasia, and canceration areas in Marjolin ulcer tissue were detected by immunohistochemical method, and the positive expression rate and protein expression level were calculated. Data were processed with Pearson chi-square test, Mann-Whitney U test, Bonferroni method, and Bonferroni correction, and Spearman correlation analysis was used to analyze the relationship among the total protein expression levels. Results: In group MU, burns accounted for 91.3% (84/92) of the causes of patients, 44.6% (41/92) of the patients had tumors in the lower extremities, 62.0% (57/92) of the patients had skin ulcer diameter of 2.1-5.0 cm, and 75.0% (69/92) of the patients had a course of disease of more than 20 years. The positive rates of VEGF, HIF-1α, and EGFR in ulcer tissue of patients in group CNU were 41.0% (41/100), 77.0% (77/100), and 83.0% (83/100), respectively, significantly higher than those of normal skin tissue of patients in group OSS [12.0% (12/100), 45.0% (45/100), and 67.0% (67/100), χ(2)=21.589, 21.522, 6.827, P<0.01]. The positive rates of VEGF, HIF-1α, and EGFR in ulcer tissue of patients in group MU were 91.3% (84/92), 100.0% (92/92), and 100.0% (92/92), respectively, which were significantly higher than those in corresponding tissue of patients in group CNU and group OSS (χ(2)=53.372, 24.772, 17.159; 120.543, 72.777, 36.661, P<0.01). In ulcer tissue of patients in group MU, the positive expression rates of VEGF in ulcer, epitheliomatous hyperplasia, and canceration areas were significantly higher than the rate in surrounding normal skin area (χ(2)=87.120, 42.368, 89.624, P<0.01); the positive expression rates of VEGF in canceration and ulcer areas were significantly higher than the rate in epitheliomatous hyperplasia area (χ(2)=22.586, 16.060, P<0.01). In ulcer tissue of patients in group MU, the positive expression rates of EGFR in ulcer, epitheliomatous hyperplasia, and canceration areas were significantly higher than the rate in surrounding normal skin area (χ(2)=21.679, 27.600, 27.600, P<0.01), but the positive expression rates of HIF-1α in four morphological areas were similar (χ(2)=3.008, P>0.05). In ulcer tissue of patients in group MU, the protein expression levels of VEGF and CD34 in ulcer, epitheliomatous hyperplasia, and canceration areas were significantly higher than those in surrounding normal skin area (Z=-6.765, -6.819; -6.765, -6.640; -6.765, -6.819, P<0.01), the protein expression levels of VEGF and CD34 in epitheliomatous hyperplasia area were significantly lower than those in ulcer area (Z=-4.484, -5.266, P<0.01), and the protein expression levels of VEGF and CD34 in canceration area were significantly higher than those in ulcer area (Z=-6.427, -6.723, P<0.01) and epitheliomatous hyperplasia area (Z=-6.427, -6.462, P<0.01). In ulcer tissue of patients in group MU, the protein expression levels of HIF-1α and EGFR in ulcer, epitheliomatous hyperplasia, and canceration areas were significantly higher than those in surrounding normal skin area (Z=-6.819, -6.393; -6.819, -6.393; -6.819, -6.393, P<0.01), the protein expression levels of HIF-1α and EGFR in ulcer area were significantly lower than those in epitheliomatous hyperplasia and canceration areas (Z=-6.118, -5.638; -6.640, -6.393, P<0.01), and the protein expression levels of HIF-1α and EGFR in canceration area were significantly higher than those in epitheliomatous hyperplasia area (Z=-6.558, -6.819, P<0.01). In ulcer tissue of patients in group MU, the total protein expression levels of VEGF, HIF-1α, and EGFR were significantly positively correlated with the total protein expression level of CD34 (r=0.772, 0.415, 0.502, P<0.01) respectively; the total protein expression level of EGFR was significantly positively correlated with that of HIF-1α (r=0.839, P<0.01), both of which were significantly positively correlated with the total protein expression level of VEGF (r=0.531, 0.440, P<0.01) respectively. Conclusions: The expressions of VEGF, HIF-1α, and EGFR are the highest in Marjolin ulcer canceration area, and EGFR may promote angiogenesis through HIF-1α or directly increasing the expression of VEGF.

Pyoderma gangrenosum-like lesion secondary to methylenetetrahydrofolate reductase mutation: an unusual presentation of a rare disease.

Pyoderma gangrenosum (PG)-like ulcerations are a rare clinical manifestation of methylenetetrahydrofolate reductase (MTHFR) mutation. We describe a patient considered to have PG who was treated with long-term high doses of systemic corticosteroids and multiple immunosuppressive agents for several years. In spite of this continuous aggressive therapy, the lesions did not improve but continued to get worse. She developed many significant and catastrophic side effects to them. When referred to our dermatology centre, on investigation, it was discovered that she has an MTHFR mutation. It seemed reasonable to presume that PG-like lesions were related to it. Treatment with a biologically active form of folate-[6S]-5-MTHF-with vitamins B6 and B12 was initiated. It was considered to be beneficial and capable of reducing hyperhomocysteinaemia and endothelial damage consequent from it. Since the institution of this treatment, the patient has begun to show very gradual but slow and incremental improvement.

Elevated Local Senescence in Diabetic Wound Healing Is Linked to Pathological Repair via CXCR2.

Cellular senescence can be broadly defined as a stable, but essentially irreversible, loss of proliferative capacity. Historically, senescence has been described as a negative outcome of advanced cellular age. It is now clear, however, that senescence represents a dynamic autonomous stress response, integral to long-term tumor suppression. Transient induction of a senescent phenotype has actually been suggested to promote regeneration in both liver and skin. Here, we explored the role of senescence in pathological aged and diabetic murine wound healing. Aged and diabetic wounds had greater numbers of senescent cells, and diabetic macrophages maintained altered retention of polarization and produced a CXCR2-enriched senescence-associated secretory phenotype (i.e., SASP). Of translational relevance, targeted expression of CXCR2 in primary human dermal fibroblasts led to paracrine induction of nuclear p21. Furthermore, a selective agonist to CXCR2 was able to reverse delayed healing in diabetic mice and accelerate ex vivo human skin wound healing. Collectively, these data suggest a hitherto unappreciated role for CXCR2 in mediating cellular senescence in pathological wound repair.

Cutaneous Lymphoproliferative Disorders: What's New in the Revised 4th Edition of the World Health Organization (WHO) Classification of Lymphoid Neoplasms.

Cutaneous lymphoproliferative disorders remain a challenging aspect of dermatopathology, in part due to the rarity of the entities and extreme variability in clinical outcomes. Although many of the entities remain unchanged, the approach to some of them has changed in the new 2016 classification scheme of the World Health Organization. Chief among these are Epstein-Barr virus-associated lymphoproliferative disorders such as Epstein-Barr virus-associated mucocutaneous ulcer and hydroa vacciniforme-like lymphoproliferative disorder, primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma, primary cutaneous acral CD8+ T-cell lymphoma, primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder, and breast implant-associated anaplastic large cell lymphoma. In addition, translocations and gene rearrangements such as those involving the 6p25.3 locus have started to inform diagnosis and classification of anaplastic large cell lymphoma and lymphomatoid papulosis. In this review, we will examine what is new in the diagnostic toolbox of cutaneous lymphoproliferative disorders.

Long noncoding RNA-antisense noncoding RNA in the INK4 locus accelerates wound healing in diabetes by promoting lymphangiogenesis via regulating miR-181a/Prox1 axis.

BACKGROUND: Slow lymphangiogenesis is one crucial reason for the impaired wound healing process in diabetes. Accumulative evidence showed that long noncoding RNA-antisense noncoding RNA in the INK4 locus (ANRIL) could influence lymphangiogenesis. Besides, miR-181a has been reported to regulate Prox1 that is essential for lymphangiogenesis. However, the relationship between ANRIL and miR-181a as well as the definitive function of ANRIL in lymphangiogenesis is not clear. METHODS: The diabetic mouse model was set up to assess the wound healing rate in vivo. Quantitative real-time polymerase chain reaction was performed to measure the expressions of ANRIL, miR-181a, and Prox1. Western blot analysis was used to assess the expressions of vascular endothelial growth factor receptor-3, lymphatic vessel hyaluronan receptor-1, Prox1, and epithelial-mesenchymal transition (EMT)-related proteins. Flow cytometry was used to assess the cell apoptosis. Wound healing assay was used to determine the effect of ANRIL on cell migration. Tube-formation assay and immunofluorescence staining were performed to determine tube-formation capacity of human dermal lymphatic endothelial cells (LECs). RESULTS: ANRIL and Prox1 were downregulated, whereas miR-181a was upregulated in the diabetic wound healing mouse model and high glucose (HG)-induced LECs. The wound healing rate and EMT were inhibited during the diabetic wound healing process. Dual-luciferase assay proved that miR-181a could bind Prox1 to repress its expression, whereas ANRIL could sponge miR-181a to recover Prox1 expression. Overexpression of ANRIL or inhibition of miR-181a rescued the impairments of survival, migration, EMT formation, and tube formation of LECs caused by HG. CONCLUSION: ANRIL could promote lymphangiogenesis during the diabetic wound healing process via sponging miR-181a to enhance Prox1 expression, which might help design new therapy to improve the wound healing efficacy for diabetes.

Ly6CHi Blood Monocyte/Macrophage Drive Chronic Inflammation and Impair Wound Healing in Diabetes Mellitus.

OBJECTIVE: Wound monocyte-derived macrophage plasticity controls the initiation and resolution of inflammation that is critical for proper healing, however, in diabetes mellitus, the resolution of inflammation fails to occur. In diabetic wounds, the kinetics of blood monocyte recruitment and the mechanisms that control in vivo monocyte/macrophage differentiation remain unknown. APPROACH AND RESULTS: Here, we characterized the kinetics and function of Ly6CHi [Lin- (CD3-CD19-NK1.1-Ter-119-) Ly6G-CD11b+] and Ly6CLo [Lin- (CD3-CD19-NK1.1-Ter-119-) Ly6G-CD11b+] monocyte/macrophage subsets in normal and diabetic wounds. Using flow-sorted tdTomato-labeled Ly6CHi monocyte/macrophages, we show Ly6CHi cells transition to a Ly6CLo phenotype in normal wounds, whereas in diabetic wounds, there is a late, second influx of Ly6CHi cells that fail transition to Ly6CLo. The second wave of Ly6CHi cells in diabetic wounds corresponded to a spike in MCP-1 (monocyte chemoattractant protein-1) and selective administration of anti-MCP-1 reversed the second Ly6CHi influx and improved wound healing. To examine the in vivo phenotype of wound monocyte/macrophages, RNA-seq-based transcriptome profiling was performed on flow-sorted Ly6CHi [Lin-Ly6G-CD11b+] and Ly6CLo [Lin-Ly6G-CD11b+] cells from normal and diabetic wounds. Gene transcriptome profiling of diabetic wound Ly6CHi cells demonstrated differences in proinflammatory and profibrotic genes compared with controls. CONCLUSIONS: Collectively, these data identify kinetic and functional differences in diabetic wound monocyte/macrophages and demonstrate that selective targeting of CD11b+Ly6CHi monocyte/macrophages is a viable therapeutic strategy for inflammation in diabetic wounds.

Proteomic analysis reveals the important roles of alpha-5-collagen and ATP5ß during skin ulceration syndrome progression of sea cucumber Apostichopus japonicus.

Apostichopus japonicus is one of the most important aquaculture species in China. Skin ulceration syndrome (SUS) of sea cucumber is a common and serious disease affected the development of A. japonicus culture industry. To better understand the response mechanisms of A. japonicus during SUS progression, the protein variations in the body wall of A. japonicus at different stages of SUS were investigated by a comparative proteomic approach based on isobaric tags for relative and absolute quantification. A total of 1449 proteins were identified from the samples at different SUS stages. Among these proteins, 145 proteins were differentially expressed in the SUS-related samples compared to those of healthy A. japonicus. These differentially expressed proteins involved a wide range of functions. Among these differentially expressed proteins, only two proteins, alpha-5-collagen and an unknown function protein, were differentially expressed during the whole progression of SUS compared with healthy A. japonicus. In addition, ATP synthase subunit beta (ATP5ß) interacted with a variety of proteins with different functions during the SUS progression. These results implied that alpha-5-collagen and ATP5ß could play important roles during the SUS progression of A. japonicus. Our study provided a new sight to understand the molecular responses of sea cucumber during the SUS progression and accumulated data for the prevention of SUS in sea cucumber aquaculture. BIOLOGICAL SIGNIFICANCE: The current study aimed to reveal how the body wall of Apostichopus japonicus response to skin ulceration syndrome (SUS). To the best of our knowledge, this is the first proteomic study analyzing the differences in protein profile of sea cucumber during the whole SUS progression. By analyzing the expression differences of the proteome via isobaric labeling-based quantitative proteomic, we identified some proteins which may play important roles during the SUS progression. According to the enrichment analyses of these proteins based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, a draft view of how the sea cucumber affected by SUS has been drawn. The common and unique differentially expressed proteins by Venn analysis showed that alpha-5-collagen was down-regulated at all stages of SUS, which had the potential as a target component for the host-directed SUS therapy. In addition, ATP5ß, a subunit of mitochondrial ATP synthase, interacting with a variety of proteins with different functions during the SUS progression. This result illustrated that energy production and metabolism could play an important role in the formation of skin ulceration and resistance to pathogens in sea cucumber. The results of this study will be helpful for researchers to gain insights into the complex molecular mechanism of SUS in sea cucumber.