Acidic biofilm microenvironment-responsive ROS generation via a protein nanoassembly with hypoxia-relieving and GSH-depleting capabilities for efficient elimination of biofilm bacteria.

Reactive oxygen species (ROS) are widely considered to the effective therapeutics for fighting bacterial infections especially those associated with biofilm. However, biofilm microenvironments including hypoxia, limited H2O2, and high glutathione (GSH) level seriously limit the therapeutic efficacy of ROS-based strategies. Herein, we have developed an acidic biofilm microenvironment-responsive antibacterial nanoplatform consisting of copper-dopped bovine serum albumin (CBSA) loaded with copper peroxide (CuO2) synthesized in situ and indocyanine green (ICG). The three-in-one nanotherapeutics (CuO2/ICG@CBSA) are capable of releasing Cu2+ and H2O2 in a slightly acidic environment, where Cu2+ catalyzes the conversion of H2O2 into hydroxyl radical (•OH) and consumes the highly expressed GSH to disrupt the redox homeostasis. With the assistance of an 808 nm laser, the loaded ICG not only triggers the production of singlet oxygen (1O2) by a photodynamic process, but also provides photonic hyperpyrexia that further promotes the Fenton-like reaction for enhancing •OH production and induces thermal decomposition of CuO2 for the O2-self-supplying 1O2 generation. The CuO2/ICG@CBSA with laser irradiation demonstrates photothermal-augmented multi-mode synergistic bactericidal effect and is capable of inhibiting biofilm formation and eradicating the biofilm bacteria. Further in vivo experiments suggest that the CuO2/ICG@CBSA can effectively eliminate wound infections and accelerate wound healing. The proposed three-in-one nanotherapeutics with O2/H2O2-self-supplied ROS generating capability show great potential in treating biofilm-associated bacterial infections. STATEMENT OF SIGNIFICANCE: Here, we have developed an acidic biofilm microenvironment-responsive nanoplatform consisting of copper-dopped bovine serum albumin (CBSA) loaded with copper peroxide (CuO2) synthesized in situ and indocyanine green (ICG). The nanotherapeutics (CuO2/ICG@CBSA) are capable of releasing Cu2+ and H2O2 in an acidic environment, where Cu2+ catalyzes the conversion of H2O2 into •OH and consumes the overexpressed GSH to improve oxidative stress. With the aid of an 808 nm laser, ICG provides photonic hyperpyrexia for enhancing •OH production, and triggers O2-self-supplying 1O2 generation. CuO2/ICG@CBSA with laser irradiation displays photothermal-augmented multi-mode antibacterial and antibiofilm effect. Further in vivo experiments prove that CuO2/ICG@CBSA effectively eliminates wound infection and promotes wound healing. The proposed three-in-one nanotherapeutics show great potential in treating biofilm-associated bacterial infections.

The structure and function of multifunctional protein ErbB3 binding protein 1 (Ebp1) and its role in diseases.

ErbB3-binding protein 1(Ebp1) has two isoforms, p42 Ebp1 and p48 Ebp1, both of which can regulate cell growth and differentiation. But these isoforms often have opposite effects, including contradictory roles in regulation of cell growth in different tissues and cells. P48 Ebp1 belongs to the full-length sequence, while conformational changes in the crystal structure of p42 Ebp1 reveals a lack of an α helix at the amino terminus. Due to the differences in the structures of these two isoforms, they have different binding partners and protein modifications. Ebp1 can function as both an oncogene and a tumor suppressor factor. However, the underlying mechanisms by which these two isoforms exert opposite functions are still not fully understood. In this review, we summarize the genes and the structures of protein of these two isoforms, protein modifications, binding partners and the association of different isoforms with diseases.

Association between systemic immune-inflammation index and psoriasis: a population-based study.

Background: The systemic immune-inflammation index (SII),as measured by lymphocyte, neutrophil and platelet counts in peripheral blood, is regarded as a favorable indicator of both inflammatory state and immune response. Psoriasis is an immune-mediated disease notable for its chronic inflammation of the entire system. Our research sought to explore the latent link between psoriasis and SII. Methods: We performed a cross-sectional investigation utilizing data extracted from the National Health and Nutrition Examination Survey (NHANES, 2009-2014). Employing multivariate linear regression models and subgroup analysis, we sought to uncover the association between SII and psoriasis. Results: This study enrolled a total of 17,913 participants as part of its research cohort. Our multivariate linear regression analysis revealed a notable and positive correlation between SII and psoriasis [1.013 (1.000, 1.026)]. As SII tertiles increased, the risk of psoriasis demonstrated an upward trend. The significant dependence on this positive association were maintained in women, BMI(≥ 30 kg/m2),non-stroke and non-cancer subjects in subgroup analysis and interaction tests. Furthermore, we identified a significant association between SII and psoriasis, characterized by two consecutive inverted U-shaped patterns. Notably, the analysis revealed the most prominent inflection point at a specific value of 797.067. Conclusions: The results indicate a significant correlation between elevated SII levels and the presence of psoriasis. However, to corroborate and strengthen these results, additional large-scale prospective studies are required.

GSH-depleting and H2O2-self-supplying hybrid nanozymes for intensive catalytic antibacterial therapy by photothermal-augmented co-catalysis.

Nanozyme-based chemodynamic therapy (CDT) has shown tremendous potential in the treatment of bacterial infections. However, the CDT antibacterial efficacy is severely limited by the catalytic activity of nanozymes or the infection microenvironments such as insufficient hydrogen peroxide (H2O2) and overexpressed glutathione (GSH). Herein, a versatile hybrid nanozyme (MoS2/CuO2) is rationally constructed by simply decorating ultrasmall CuO2 nanodots onto lamellar MoS2 platelets of hydrangea-like MoS2 nanocarrier via a covalent Cu-S bond. The MoS2/CuO2 nanozyme exhibits the peroxidase-mimic activity for catalytically converting H2O2 produced by acid-triggered decomposition of the decorated CuO2 into hydroxyl radical (•OH). Meanwhile, the MoS2/CuO2 can consume GSH overexpressed in the infection sites via redox reaction mediated by polyvalent transition metal ions (Cu2+ and Mo6+) for enhanced CDT. More importantly, MoS2 support can promote the conversion of Cu2+ to Cu+ by a co-catalytic reaction based on the Mo4+/Mo6+ redox couples, and provide photonic hyperthermia (PTT) to augment the peroxidase-mimic activity. The developed MoS2/CuO2 nanozymes possesses a desirable catalytic property, as well as a remarkably improved antibacterial efficiency both in vitro and in vivo. Taken together, this study proposes a synergetic multiple enhancement strategy to successfully construct the versatile hybrid nanozymes for intensive in vivo PTT/CDT dual-mode anti-infective therapy. STATEMENT OF SIGNIFICANCE: Chemodynamic therapy (CDT) has shown great potentialities in the treatment of bacterial infections, while its therapeutic efficiency is severely limited by the infection microenvironments such as insufficient hydrogen peroxide (H2O2) and overexpressed glutathione (GSH). Here, we rationally construct a hybrid nanozyme (MoS2/CuO2) with peroxidase-like activity that can enhance CDT by regulating local microenvironments, that is, simultaneously self-supplying H2O2 and consuming GSH. Importantly, MoS2 support can promote the conversion of Cu2+ to Cu+ by the Mo4+/Mo6+ redox couples, and provide photonic hyperthermia (PTT) to augment the peroxidase-mimic activity. The developed MoS2/CuO2 shows desirable PTT/CDT dual-mode antibacterial efficacy both in vitro and in vivo. This study proposes a versatile hybrid nanozyme with multiple enhancement effects for intensive in vivo anti-infective therapy.

A biofilm microenvironment-responsive one-for-all bactericidal nanoplatform for photothermal-augmented multimodal synergistic therapy of pathogenic bacterial biofilm infection.

Multimodal synergistic bactericidal agents display great potential for fighting biofilm infections. However, the rational design of biofilm microenvironment (BME)-activatable therapeutic agents with excellent specificities, effective eradications and minimal side effects remains a great challenge. Herein, we show a BME-responsive one-for-all bactericidal nanoplatform consisting of Fe3+-doped polydopamine (Fe/PDA)-capped ZnO nanoparticles with a successive assembly of methylene blue (MB) and poly(ethylene glycol) (PEG). In an acidic BME (pH 5.5), the constructed nanoagent (ZnPMp) can realize the co-delivery of dual metal ions (Zn2+ and Fe3+) and MB, and the latter shows an activated photodynamic antibacterial activity when irradiated with 635 nm laser. Zn2+ produced from acid-sensitive dissolution of ZnO is an effective chemical antibacterial agent. Additionally, the released Fe3+ is reduced to Fe2+ by glutathione (GSH) overexpressed in the BME to generate Fe2+/Fe3+ redox couples, which exhibit Fenton catalytic activity to convert endogenous H2O2 to hydroxyl radicals (˙OH) for chemodynamic sterilization and GSH depletion ability to improve ˙OH-induced oxidative damage. Interestingly, the hyperthermia caused by the Fe/PDA layer assisted with 808 nm laser can damage directly bacterial cells, accelerate the release of Zn2+, Fe3+and MB, and promote the catalytic activity of Fe2+/Fe3+ redox couples for photothermal-augmented multimodal antibiofilm therapy. With the help of dual lasers, ZnPMp displays the broad-spectrum antibacterial effect, inhibits effectively the formation of biofilms, and more importantly eliminates bacteria deep in mature biofilms. In addition, ZnPMp can be used to treat biofilm-related infections in vivo with excellent therapeutic performance and minimal toxicity. Overall, the developed ZnPMp may serve as a potential nano-antibacterial agent for intensive anti-infective therapy.

Rapid In Situ Deposition of Iron-Chelated Polydopamine Coating on the Polyacrylamide Hydrogel Dressings for Combined Photothermal and Chemodynamic Therapy of Skin Wound Infection.

Pathogenic bacterial infections of skin wounds have caused a significant threat to clinical treatment and human life safety. Here, we develop a bactericidal hydrogel dressing consisting of a polyacrylamide (PAM) hydrogel framework with in situ surface-deposition of iron-dopped polydopamine (FePDA). The prepared hydrogel dressing (FePDA-PAM) has a compact surface, good tensile strength, and excellent elastic recovery ability. The introduction of Fe3+ ions improve the photothermal therapy (PTT) efficiency of the PDA and endow the hydrogel dressing with chemodynamic therapy (CDT) properties. In vitro experiments show that the antibacterial effect of FePDA-PAM hydrogel on Staphylococcus aureus reach nearly 100% under the combined action of H2O2 and 808 nm near-infrared (NIR) laser, indicating an excellent combined antibacterial property of PTT and CDT. Furthermore, the FePDA-PAM + H2O2 + NIR treatment group in the in vivo antibacterial experiments displays lowest relative wound area and optimal wound healing within 5 days of treatment, thereby indicating the intensive skin wound disinfection. To summarize, the FePDA-PAM hydrogel has simple preparation and good biosafety. It may serve as a potential wound dressing for the combined PTT/CDT dual-mode antibacterial therapy.

Normal mesenchymal stem cells can improve the abnormal function of T cells in psoriasis via upregulating transforming growth factor-ß receptor.

Psoriasis, a chronic inflammatory skin disease, is a refractory disorder. Previous studies have shown that the imbalance of the T-helper (Th)17/regulatory T cells (Treg) results in the immune imbalance of T cells in psoriatic patients, and that mesenchymal stem cells display an immunosuppressive role by promoting the differentiation of T cells into Treg, leading to a reduction in the proportion of Th17/Treg. Utility of mesenchymal stem cells is becoming a new approach for the treatment of immune disorders. Following co-culture of dermal mesenchymal stromal cells (DMSC) and CD3+ T cells with or without transforming growth factor (TGF)-ß receptor inhibitor, the biological function and relative signal pathway of CD3+ T cells were assessed by flow cytometry, transwell, real-time polymerase chain reaction and western blotting, respectively. Normal DMSC were more potent than psoriatic DMSC in inhibition of CD3+ T-cell proliferation, and stimulation of CD3+ T-cell apoptosis than psoriasis DMSC. Moreover, normal DMSC decreased the ratio of Th17/Treg, while enhancing the immunosuppressive effect of Tregs on effector T cells. However, TGF-ß receptor (TGF-ßR) inhibitor attenuated the effect of normal DMSC on CD3+ T cells and Th17/Treg ratio. Additionally, the normal DMSC were more potent than the psoriatic DMSC in increasing TGF-ß receptors and activation of TGF-ß/SMAD pathway in psoriatic CD3+ T cells. In conclusion, normal DMSC can partially improve the biological function and immunosuppressive ability of psoriatic CD3+ T cells, possibly via upregulating the TGF-ß receptors.

MiR-155 inhibits TP53INP1 expression leading to enhanced glycolysis of psoriatic mesenchymal stem cells.

BACKGROUND: Psoriasis is a systemic disease with multiple associated comorbidities, including metabolic syndrome. Studies suggest that chronic inflammation is a central link between psoriasis and metabolic abnormalities. MiR-155 is a well-known microRNA that plays an important regulatory role in inflammation. Studies from our group and others have demonstrated an upregulation of miR-155 in psoriasis. OBJECTIVES: Here, we investigated whether miR-155 regulates glycolysis of psoriasis and the underlying mechanisms. METHODS: Human dermal-derived mesenchymal stem cells (MSC) were treated with miR-155 mimic or inhibitor, followed by assessments of cells proliferation, metabolism and inflammatory response. Target gene prediction and GO/Pathway analysis were used to screen the putative targets involved in the pathways of metabolism, and verified by dual-luciferase reporter assay. To determine whether TP53INP1/p53 signaling pathway is involved in miR-155-mediated regulation of glycolysis, changes in glycolysis were assessed in psoriatic MSC (PM) with either overexpression or knockdown of TP53INP1, or activation/inhibition of p53 signaling pathway. RESULTS: Our results showed that miR-155 promoted proliferation, migration, inflammatory response and metabolite levels of MSC, while inhibiting apoptosis. In comparison to the MSC from normal subjects, the glycolysis levels were increased in PM. GO and KEGG analyses indicated that TP53INP1 was miR-155 target gene with negative regulation of cellular metabolic process. Moreover, miR-155 promoted glycolysis of PM by negative regulation of TP53INP1/p53 signaling pathway. CONCLUSIONS: MiR-155 could promote glycolysis via targeting of TP53INP1 in PM. These findings suggest a pathogenic role of miR-155 in metabolic abnormalities in psoriasis.

Dermal Mesenchymal Stem Cells from Psoriatic Lesions Stimulate HaCaT Cell Proliferation, Differentiation, and Migration via Activating the PI3K/AKT Signaling Pathway.

BACKGROUND: Psoriasis is a chronic inflammatory skin disease characterized by excessive proliferation and abnormal differentiation of keratinocytes. Dermal mesenchymal stem cells (DMSCs) are not only involved in the regeneration of skin tissue, but also can regulate skin microenvironment by secreting cytokines. However, whether and how psoriatic DMSCs regulate proliferation and differentiation of keratinocytes remains unknown. OBJECTIVE: To study the effects of psoriatic DMSCs on the proliferation, differentiation, and migration of keratinocytes and the underlying mechanisms. METHODS: Following co-cultures of HaCaT cells with either psoriatic DMSCs (p-DMSCs) or DMSCs from normal volunteers (n-DMSCs), HaCaT cell proliferation was assessed using CCK-8 and EDU incorporation assay, while scratch assay and transwell assay were used to assess cell migration. qRT-PCR was used to determine expression levels of mRNA for cell proliferation (Ki-67) and differentiation (keratin 5, involucrin, and filaggrin). Western blot was used to measure expression levels of proteins associated with keratinocyte proliferation and differentiation in cultured HaCaT cells treated with or without PI3K inhibitor. ELISA assay was used to measure expression profile of stem cell factor (SCF), epidermal growth factor (EGF), and interleukin-11 (IL-11) within the co-culture supernatants. RESULTS: The results showed that p-DMSCs displayed a higher potency than n-DMSCs in stimulating proliferation, differentiation, and migration of HaCaT cells. Expression levels of PI3K and AKT proteins were markedly increased in HaCaT cells co-cultured with DMSCs versus HaCaT cell culture alone. Moreover, inhibition of the PI3K/AKT signaling pathway reversed the effect of p-DMSCs on proliferation, differentiation, and migration of HaCaT cells. Compared with n-DMSCs, the p-DMSCs showed increased secretion of IL-11, EGF, and SCF. CONCLUSION: p-DMSCs stimulate HaCaT cell proliferation, differentiation and migration via activating the PI3K/AKT signaling pathway, providing a new insight into the pathogenesis of psoriasis.

Effect of Hypothermia on Serum Myelin Basic Protein and Tumor Necrosis Factor-α in Neonatal Hypoxic-Ischemic Encephalopathy.

OBJECTIVE: Multiple randomized controlled trials have shown that hypothermia is a safe and effective treatment for neonatal moderate or severe hypoxic-ischemic encephalopathy (HIE). The neuroprotective mechanisms of hypothermia need further study. The aim of this study was to investigate the effect of hypothermia on the serum levels of myelin basic protein (MBP) and tumor necrosis factor-α (TNF-α) as well as neurodevelopmental outcomes in neonatal HIE. STUDY DESIGN: Eighty-five neonates with moderate-to-severe HIE were divided into a hypothermia group (n = 49) and a control group (n = 36). Serum levels of MBP and TNF-α within 6 hours after birth and after 3 days of treatment were determined by enzyme-linked immunosorbent assay, and neurodevelopmental outcome at the age of 12 to 15 months was assessed by using the Gesell development scale. RESULTS: After 3 days of treatment, serum levels of MBP and TNF-α in the control group were not significantly different from levels before treatment (p > 0.05), and serum levels of MBP and TNF-α in the hypothermia group were significantly lower than levels before treatment (p < 0.05). Serum levels of MBP and TNF-α were significantly negatively correlated with developmental quotient (DQ; r = - 0.7945, p = 0.0000; r = - 0.7035, p = 0.0000, respectively). Serum levels of MBP and TNF-α in neurodevelopmentally impaired infants were significantly higher than those in infants with suspected neurodevelopmental impairment and those in neurodevelopmentally normal infants (both p < 0.01). The rate of reduction of neurodevelopmental impairment was higher among infants in the hypothermia group than among those in the control group (χ2 = 16.3900, p < 0.05). CONCLUSION: Hypothermia can reduce serum levels of MBP and TNF-α in neonates with HIE. Inhibiting the release of TNF-α may be one of the mechanisms by which hypothermia protects the myelin sheath. KEY POINTS: · Hypothermia can reduce serum levels of MBP and TNF-α in neonatal HIE.. · Hypothermia improves neurodevelopmental outcomes and reduces the rate of neurodevelopmental impairment.. · Hypothermia is a feasible and effective treatment for neonates with moderate or severe HIE..

Role of psoriatic keratinocytes in the metabolic reprogramming of dermal mesenchymal stem cells.

BACKGROUND: Psoriasis is an immune-mediated inflammatory skin disease, featured by epidermal hyperproliferation. Psoriasis exhibits metabolic abnormalities, which can further aggravate the condition of psoriasis. The present study aimed to investigate the role of psoriatic keratinocytes (KCs) in the metabolic reprogramming of dermal mesenchymal stem cells (DMSCs). METHODS: Dermal mesenchymal stem cells were cocultured with primary KCs either from psoriatic lesions or from normal subjects using Transwell plate. Glycolysis and mitochondrial metabolism of DMSCs were detected by Seahorse Metabolic Analyzer. Expression levels of proteins were analyzed by Western blotting. DMSCs proliferation was assessed using 5-ethynyl-2'-deoxyuridine assay and Cell Counting Kit-8. RESULTS: In comparison with normal KCs, coculture of psoriatic KCs with DMSCs dramatically increased glycolytic and mitochondrial metabolism, and expression levels of stem cell factor, epidermal growth factor, glucose transporter 1, and c-Myc. Moreover, psoriatic KCs were more potent than normal KCs in the stimulation of DMSC proliferation. CONCLUSIONS: In conclusion, psoriatic KCs display a higher potency in metabolic reprogramming and stimulation of DMSC proliferation, possibly contributing to the pathogenesis of psoriasis. However, whether the intervention of metabolic reprogramming of DMSCs can alleviate psoriasis remains to be determined.

Immunomodulatory effect of psoriasis-derived dermal mesenchymal stem cells on TH1/TH17 cells.

T cell-mediated inflammation plays an important role in the development of psoriasis. Mesenchymal stem cells (MSCs) are a population of multipotent cells that regulate the T cell-mediated immune response. To investigate the effects of psoriatic dermal mesenchymal stem cells (p-DMSCs) on proliferation, apoptosis and differentiation of T cells. p-DMSCs and normal DMSCs (n-DMSCs) were isolated from psoriatic skin and normal healthy controls, respectively, and co-cultured with activated T cells isolated from healthy volunteers using a Transwell system. Proliferation and apoptosis of T cells were assessed by cell count and flow cytometry, respectively. Expression levels of transcription factors associated with subtypes of T cells and cytokines were measured by qRT-PCR and western blot. Both p-DMSCs and n-DMSCs inhibited T cell proliferation and cytokine production. Similarly, the presence of p-DMSCs and n-DMSCs decreased the expression levels of both T-bet and ROR-γt in T cells. However, n-DMSCs exhibited a stronger inhibitory effect than p-DMSCs on T cell proliferation, cytokine production, and T-bet and ROR-γt expression. These results suggest that the effect of p-DMSCs on T cell function could contribute, at least in part, to the pathogenesis of psoriasis.

The effects of human dermal-derived mesenchymal stem cells on the keratinocyte proliferation and apoptosis in psoriasis.

Psoriasis is a common chronic inflammatory skin disease, characterized by epidermal hyperproliferation. Mesenchymal stem cells (MSCs) regulate inflammation and vascular proliferation in the psoriasis lesions. Whether dermal-derived mesenchymal stem cells (DMSCs), the main MSCs in the dermis, regulate keratinocyte proliferation and apoptosis remains unknown. In the present study, we assessed the proliferation and apoptosis of keratinocytes cocultured with DMSCs isolated from either normal or psoriatic involved skin. Cell growth and apoptotic rates were determined using Cell Count Kit-8 and annexin V-FITC staining, respectively. In addition, EDU kit was also used to measure the rate of keratinocyte proliferation. Our results showed that psoriatic DMSCs (pDMSCs) were more potent than normal DMSCs (nDMSCs) in stimulating keratinocyte proliferation. In contrast, the apoptotic rate and expression levels of caspase-3 protein were lower in pDMSC-treated than nDMSC-treated keratinocytes (p < 0.001). Moreover, significantly higher contents of IL-6, IL-8, TNF-α and IFN-γ were found in the culture medium of pDMSCs than in that of nDMSCs. In conclusion, pDMSCs were more potent than nDMSCs in stimulation of keratinocyte proliferation and secretion of proinflammatory cytokines, but weaker in promoting apoptosis.

Agromyces laixinhei sp. nov. isolated from bat feces in China.

Three rod-shaped, Gram-stain-positive, and catalase-positive, phenotypically closely related isolates (HY052T, HY050, and HY045) were obtained from fecal samples collected from bats in Guangxi province and Chongqing city of China. Circular, smooth, light-yellow colonies appeared on brain heart infusion plate after 24-48 h incubation at 28°C. The optimal pH for growth was between 6.0 and 7.5. Based on 16S rRNA, the three isolates were phylogenetically related to Agromyces terreus DS-10T, Agromyces aureus AR33T, Agromyces salentinus 20-5T, Agromyces allii UMS-62T, Agromyces lapidis CD55T, and Agromyces italicus CD1T. Moreover, based on 296 core genes, the phylogenomic tree indicated that the three isolates clustered together, closest to Agromyces cerinus VKM Ac-1340T and Agromyces fucosus VKM Ac-1345T but separated distantly from other Agromyces species. The average nucleotide identity values between strain HY052T and other Agromyces species ranged from 79.3% to 87.9%, lower than the 95-96% threshold. Furthermore, the genome of strain HY052T contains a circular chromosome of 3,437,203 bp with G + C content of 69.0 mol%. Main fatty acids were anteiso-C15:0 and anteiso-C17:0. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, and unidentified glycolipids. Rhamnose, ribose, and glucose were the primary cell wall sugars. The major peptidoglycan amino acids included alanine, glutamic acid, glycine, and 2,4-diaminobutyric acid. An additional remarkable difference from other Agromyces species is that MK-12 was the sole menaquinone in strain HY052T. Based on results from the polyphasic characterizations performed in this study, our isolates are proposed to be members of a novel species in genus Agromyces, named Agromyces laixinhei. The type strain is HY052T (= CGMCC 1.17175T = JCM 33695T).

Psoriatic mesenchymal stem cells stimulate the angiogenesis of human umbilical vein endothelial cells in vitro.

OBJECTIVE: To investigate the regulation of psoriatic dermal mesenchymal stem cells (p-DMSCs) in the expression of vascular growth factor (VEGF), and migration and angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro. METHODS: A co-culture model of HUVECs and dermal mesenchymal stem cells (DMSCs)was used in this study. After 7-day co-culture, changes in expression levels of VEGF mRNA and protein in HUVECs were assessed using RT-PCR and Western Blotting, respectively. Migration and tubular formation of HUVECs were also assessed following co-culture of DMSCs and HUVECs. RESULTS: In comparison to either HUVECs alone or co-culture of n-DMSCs and HUVECs, co-culture of HUVECs and p-DMSCs significantly increased expression levels of both VEGF mRNA (p < 0.01 vs. HUVECs alone) and protein in HUVECs (p < 0.001 vs. both HUVECs alone and HUVECs co-cultured with n-DMSCs). Moreover, p-DMSCs stimulated HUVEC migration and vascular formation (p < 0.05 vs. both HUVECs alone and co-culture of n-DMSCs and HUVECs). CONCLUSION: Psoriatic DMSCs can upregulate VEGF expression, and stimulate migration and angiogenesis of HUVECs, suggesting a pathogenic role of p-DMSCs in psoriasis.

MicroRNA-31 Overexpression may Aggravate the Formation of Psoriasis-like Lesions by STAT3/p53 Pathway.

Background: Psoriasis is a chronic inflammatory skin disease with an unknown pathogenesis. Recently, miR-31 have been shown to play an important role in psoriasis. Moreover, STAT3/p53 pathway has been used in tumor studies, but rarely in psoriasis studies. Aims: The present study aimed to investigate the role of STAT3/p53 pathway in psoriasis-like lesions in a mouse model of miR-31 overexpression. Methods: All mice (n = 44) were divided into four groups: normal mice treated with Vaseline® (NV; n = 10), normal mice treated with imiquimod (NI; n = 12), miR-31-overexpressing mice treated with Vaseline® (MV; n = 10), and miR-31-overexpressing mice treated with imiquimod (MI; n = 12). Then, we assayed the expression of STAT3 and p53. Results: Our results showed that at the protein level (P < 0.01) and gene level (4.45 times), the expression of STAT3 in the MV group was higher than that in the NV group, and at the protein level (P < 0.01) and gene level (11.43 times), the expression of STAT3 in the MI group was higher than that in the NI group. At the protein level, the expression of p53 in MV group was higher than that in the NV group (P < 0.05), and the expression of p53 in MI group was higher than that in the NI group (P < 0.01). Conclusions: Our findings indicate that overexpression of miR-31 causes upregulation of STAT3, which further brings about upregulation of p53, and eventually leads to serious psoriasis skin lesion.

The regulation of dermal mesenchymal stem cells on keratinocytes apoptosis.

Dermal mesenchymal stem cells (DMSCs) are progenitor cells with the capacity of self-renewal, multilineage differentiation, and immunomodulation, which were reported to induce the proliferation of keratinocytes, however the regulation on keratinocytes apoptosis was unknown. In this study, we isolated DMSCs from normal skin and co-cultured with keratinocytes, and then detected apoptosis of keratinocytes by flow cytometry and expression of apoptosis associated proteins by western blot. The mRNA expression profile of normal DMSCs was investigated by RNA sequencing. The results of our study presented that the DMSCs promoted HaCaT cells apoptosis both in early apoptotic state (13.8 vs. 2.9, p < 0.05) and late apoptotic state (4.2 vs. 0.7, p < 0.05). The expression of apoptosis associated proteins caspase-3 (3.51 vs. 1.99, p < 0.05) and lymphoid enhancer-binding factor 1 (3.10 vs. 0.83, p < 0.05) were upregulated. However, the cell cycle protein cyclin E1 was similar (9.38 vs. 9.05, p > 0.05). Moreover, 33 genes with the function of induced cell apoptosis were highly expressed in DMSCs, including insulin-like growth factor-binding protein 4 (2828.13), IGFBP7 (1805.69), cathepsin D (1694.34), cathepsin B (CTSB, 1641.40) and dickkopf WNT signaling pathway inhibitor 1 (DKK1, 384.79). This study suggested DMSCs induce the apoptosis of keratinocytes through non-G1/S phase blockade via highly expression of apoptosis inducer.

Dermal mesenchymal stem cells promoted adhesion and migration of endothelial cells by integrin in psoriasis.

The unusual dilatation of dermal capillaries and angiogenesis played important roles in psoriasis. Some genes and proteins of dermal mesenchymal stem cells (DMSCs) from psoriasis are abnormal and related to the function of endothelial cells (ECs). The present study was aimed to evaluate whether psoriatic DMSCs could affect adhesion and migration of ECs through neovascularization-related integrins in psoriasis. Human DMSCs, collected from psoriasis lesions and healthy skin, respectively, were cocultured with human umbilical vein endothelial cells (HUVECs). The expression levels of three integrins, that is, αvß3, αvß5, and α5ß1 in HUVECs were tested by quantitative real-time polymerase chain reaction and Western blot analysis. The adhesion and migration of HUVECs were detected by adhesion assay and migration assay. The results showed that in psoriasis group, the expression of αVß3 and α5ß1 of HUVECs markedly increased 2.50- and 3.71-fold in messenger RNA levels, and significantly increased 1.63- and 1.92-fold in protein levels, comparing to healthy control group (all p < .05). But ß5 was not significantly different between the two groups (p > .05). In addition, compared with control, psoriatic DMSCs promoted HUVECs adhesion by 1.62-fold and migration by 2.91-fold (all p < .05). In conclusion, psoriatic DMSCs impact HUVECs adhesion and migration by upregulating the expression of integrins αVß3 and α5ß1.

Psoriasis-associated angiogenesis is mediated by EDIL3.

The dermal mesenchymal stem cells (DMSCs) from psoriasis display higher expression level of epidermal growth factor-like repeats and discoidin I-like domains 3 (EDIL3), while EDIL3 can bind integrins, including αvß3 and αvß5, to regulate angiogenesis. To assess the role of EDIL3 derived from DMSCs of psoriasis (P-DMSCs) in angiogenesis, in vitro, EDIL3 of DMSCs from psoriasis was silenced by interfering EDIL3. Then the efficacy of silencing EDIL3 was tested by fluorescent flag, qRT-PCR and western blotting. And, in vitro, the relationship of EDIL3 in DMSCs with the angiogenesis of HUVECs were investigated through co-culture system. In vivo, EDIL3 recombinant protein was injected into IMQ cream-induced psoriasis-like skin lesions of mouse and EDIL3-associated tube formation were determined using Image J software. Our results showed the capacity of the adhesion, migration and tube formation of HUVECs in all psoriatic DMSCs groups were significantly higher compared with the control and si-EDIL3 groups (all P<0.05) in vitro. Moreover, under stimulated by EDIL3 recombinant protein, EDIL3-associated tube formation was dramatically elevated in vivo (P<0.01). In this study, EDIL3 could promote the adhesion, migration and tube formation of ECs and participant in the angiogenesis pathogenesis of psoriasis through affecting biological function on ECs both in vitro and in vivo. The results suggest a potential role of the critical pro-angiogenic factor EDIL3 in psoriasis therapy.

Nocardioides dongxiaopingii sp. nov., isolated from leaves of Lamiophlomis rotata on the Qinghai-Tibet Plateau.

Two novel Gram-stain-positive, irregular rod-shaped actinomycetes, S-1144T and 4053, were isolated from leaves of Lamiophlomis rotata on the Qinghai-Tibet Plateau, PR China. Cells were aerobic, catalase-positive and oxidase-negative. Colonies on Reasoner's 2A agar were light yellow, circular, shiny, smooth and convex after 2 days of incubation. The isolates grew optimally at 25 °C, pH 7.5 and with 0 % (w/v) NaCl. The results of polyphasic analyses indicated that strain S-1144T belonged to the genus Nocardioides and its close phylogenetic neighbours (16S rRNA gene sequence similarity) were Nocardioides litoris DSM 103718T (98.4 %), Nocardioides rubriscoriae DSM 23986T (98.2%) and Nocardioides plantarum DSM 11054T (97.8 %). The genome of strain S-1144T showed less than 70 % digital DNA-DNA hybridization and < 95-96 % average nucleotide identity values to the above reference strains. The DNA G+C content of strain S-1144T was 73.5 mol%. MK-8(H4) was the predominant respiratory quinone (96.0 %) and llLL-2,6-diaminopimelic acid was the diagnostic diamino acid in the cell-wall peptidoglycan. The polar lipid profile of strain S-1144T consisted of diphosphatidylglycerol, phosphatidylglycerol, three unidentified phospholipids, one unidentified glycolipid and one unidentified lipid. The major cellular fatty acids were iso-C16 : 0, C17 : 1 ω8c, C17 : 0 and C18 : 1 ω9c. On the basis of obtained data, strain S-1144T represented a novel species of the genus Nocardioides, for which the name Nocardioides dongxiaopingii sp. nov. is proposed. The type strain is S-1144T (=CGMCC 4.7568T=JCM 33469T).