IL-36γ promotes psoriasis-like features in keratinocytes in an imiquimod-induced murine model of psoriasis

IntroductionPsoriasis is a recurrent, chronic inflammatory skin disease with complex pathogenesis. The disease imposes a heavy burden on patients. Interleukin (IL)-36γ belongs to the IL-36 family and is predominantly expressed by epithelial cells. IL-36γ is upregulated in psoriasis lesions. However, the effects of IL-36γ in keratinocytes remain unclear.Material and methodsEighteen IL-36γ-deficient mice were divided into three groups: the vaseline group, the imiquimod (IMQ) group, and the IMQ/IL-36γ group. Vaseline or IMQ was administered for 6 consecutive days. The severity of psoriasis-like lesions was evaluated using a modified Psoriasis Area and Severity Index (PASI) scoring system. Production of cytokines and expression of differentiation markers were assessed by immunohistochemistry.ResultsIMQ-induced psoriasis lesions were significantly more severe in IMQ/IL-36γ-treated mice compared with vaseline-treated and IMQ-treated mice, as shown by an exacerbated inflammatory phenotype, increased numbers of blood vessels, increased infiltration of cells, and increased epidermal thickness. Expression of loricrin and keratin 5 in skin lesions was decreased following treatment with IL-36γ. Levels of IL-17A, interferon-γ, β-catenin and Dickkopf-related protein 1 were elevated in keratinocytes within psoriatic lesions following IL-36γ stimulation.ConclusionsTogether, these data showed that IL-36γ contribute to abnormal keratinocytes proliferation and keratinocyte-related proinflammatory cytokines, and suggest that IL-36γ may play an important role in the pathogenesis of psoriasis.

Effect of Pentoxifylline on Diabetic Neuropathic Pain in Rats

Background and Aim Diabetic neuropathy (DN) is the most common diabetic complication, which has a lifetime prevalence of about 50%. About 20 to 30% of patients with DN suffer from neuropathic pain. This study was designed to investigate the role of early and late treatment of pentoxifylline (PTX) in management of diabetic neuropathic pain (DNP). Method Diabetic rats were administered PTX (50 and 200 mg/kg/day, in drinking water) either one week after STZ injection and for 7 weeks or 6 weeks after STZ injection and for 2 weeks. Mechanical allodynia were assessed weekly, Iba-1 and GFAP immunorectivity, spinal NFκB & spinal sciatic TNF-α were estimated at the end of the study. Epidermal thickness of the food pad and Na+/K+-ATPase activity in sciatic nerve were measured as an outcome measure for predegenerative markers of DN. Results The results of the present study suggest that activated microglia and not astrocytes are involved in the development of experimental diabetic neuropathy. PTX inhibit neuroimmune activation of microglia, reduce the levels of proinflammatory cytokines and improve epidermal thickness of the food pad and Na+/K+-ATPase activity in sciatic nerve. Only PTX 200 mg/kg/day when administered early and late treatment in diabetic rats produced antiallodynic effect. Conclusion PTX is a fundamental drug whose antiallodynic effect depends on the pathogenetic mechanisms and has the ability to halt or inhibit the progression of the disease. The earlier the use of PTX in the developmental phase of mechanical hyperalgesia the more the antiallodynic effect of the drug.

A Histological study on the effect of Platelet Rich Plasma on Hair Growth in Male Albino Rat Model of Androgenic Alopecia

Background Androgenetic alopecia (AGA) is the commonest cause of hair loss in men with limited treatment options. Platelet-rich plasma (PRP) is defined as an autologous concentration of plasma with a greater count of platelets than that of whole blood. Its action depends on the released growth factors from platelets. It has been investigated and used in numerous fields of medicine. Recently, PRP has received growing attention as a potential therapeutic tool for hair loss. Aim of the work This study aimed at evaluating the efficacy of PRP therapy on experimentally induced AGA in male albino rats. Materials and Methods Eighteen rats were divided into 3 groups - Group I (the control group), Group II (testosterone group): rats were injected 0.1 ml testosterone daily in the shaved area of the dorsum , Group III (PRP group): rats were injected 0.1 ml of testosterone daily+ 0.1 ml of PRP every 3 days in the shaved area of their dorsum. After 21 days from the start of the experiment, skin samples were collected from the site of injection and prepared for histological examination by hematoxylin and eosin stain and immunohistochemical examination by anti Ki 67. Morphometrical and statistical analysis were performed. Results Testosterone group when compared to the control group showed a significant decrease in the mean epidermal thickness, decreased mean number of anagen hair follicles, increase in the mean number of telogen hair follicles and decreased anagen/telogen ratio, all were statistically significant (P < 0.05). PRP group showed significant increase in the mean number of anagen hair follicles (p < 0.05), and a decrease in the mean number of telogen hair follicles (p < 0.05). This resulted in an increase in anagen/telogen ratio. There was also a significant increase in the mean epidermal thickness in the PRP group as compared to the other groups (p < 0.05). Immunohistochemical examination of anti Ki 67 stained sections showed significant decrease of the mean number of Ki 67 positive basal epidermal cells (P < 0.05) in the testosterone group compared to control group, and an increase in the mean number of Ki 67 positive basal epidermal cells in the PRP group (p < 0.05) as compared to the control group and the testosterone group. Conclusion Our data suggest that PRP injections may have a positive therapeutic effect on experimentally induced androgenic alopecia in adult male albino rats.

Mesenchymal stromal cells therapy alone does not lead to the complete restoration of the skin parameters in diabetic foot patients within a 3-year follow-up period

Introduction: Mesenchymal stromal cells (MSCs) administration is an effective option for the treatment of diabetic foot ulcers (DFUs). However, to date, studies assessing long-term outcomes and evaluating skin parameters after cell-based therapy are lacking. We presented the clinical outcomes of 3 patients, treated for DFUs with the bone marrow MSCs 3 years earlier. Methods: Ultrasound examination was used to compare collagen density and epidermal thickness in areas of healed ulcers in comparison with non-affected skin used as a control. Ultrasound and dermatoscopy were used to exclude neoplasm formation, to assess scar contracture and wound recurrence. Results: In all patients, no ulcer recurrence was detected, which was lower than the expected 60% rate of re-ulceration in diabetic patients in a 3-year period (OD [odds ratio] = 0.095, P = 0.12). No neoplasm formation, no contracture of hypertrophic scar, and adjacent tissue were registered. Collagen ultrasound density was decreased by 57% (P = 0.053) and epidermal thickness was increased by 72% (P = 0.01) in the area of healed ulcers in all patients. Conclusion: MSCs therapy alone did not result in the complete restoration of the skin parameters within a 3-year period. MSCs may represent important adjuvant to the therapy, however, other novel approaches are required to achieve better results.

Developmental genetics of color pattern establishment in cats

Intricate color patterns are a defining aspect of morphological diversity in the Felidae. We applied morphological and single-cell gene expression analysis to fetal skin of domestic cats to identify when, where, and how, during fetal development, felid color patterns are established. Early in development, we identify stripe-like alterations in epidermal thickness preceded by a gene expression pre-pattern. The secreted Wnt inhibitor encoded by Dickkopf 4 plays a central role in this process, and is mutated in cats with the Ticked pattern type. Our results bring molecular understanding to how the leopard got its spots, suggest that similar mechanisms underlie periodic color pattern and periodic hair follicle spacing, and identify targets for diverse pattern variation in other mammals.

Treatment of atopic dermatitis using non-thermal atmospheric plasma in an animal model

Cold atmospheric plasma (CAP) has been incorporated into various fields, including promotion of cutaneous wound healing. Atopic dermatitis (AD) is a chronic cutaneous condition characterized by inflammation-induced skin wounds and impaired skin barrier function. To investigate whether CAP may improve AD using an animal model. Dermatophagoides farinae extracts (DFE)-induced murine models of AD were used in this study. The plasma-treated group received a total of 6 CAP treatments during 2 weeks, while the control group did not receive any treatment. Differences in dermatitis severity, transepidermal water loss (TEWL), serum level of immunoglobulin (Ig) E and epidermal thickness were evaluated in both groups. The dermatitis severity was significantly improved by CAP treatment. TEWL was lower in the plasma-treated group compared with the non-treated control group. Serum Ig E dropped significantly after treatment with CAP. Difference in epidermal thickness of the ear skin was not significant between the plasma-treated and non-treated groups. Localized treatment of AD with CAP decreases dermatitis severity, TEWL, and serum Ig E level. These results show CAP’s potentials as a novel therapeutic modality for AD.

L-Theanine Alleviates IMQ-Induced Psoriasis Like Skin Inflammation by Downregulating the Production of IL-23 and Chemokines

Psoriasis, the most common skin inflammatory disease, is characterized by massive keratinocyte proliferation and immune cell infiltration into epidermis. L-Theanine (L-THE), a nonproteinogenic amino acid derived from green tea (Camellia sinensis), has been proved to possess the properties of anti-inflammatory, antidepressants and neuroprotective. However, whether L-THE has a therapeutic effect on psoriasis is still unknown. In this study, we found that the epidermal thickness and inflammatory response were significantly reduced in Imiquimod (IMQ)-induced psoriasis mice by applying with L-THE on mice skin. The expression of proliferation and inflammation associated genes such as keratin 17, IL-23 and CXCL1-3 was also downregulated by L-THE. Furthermore, L-THE inhibited the production of IL-23 in dendritic cells (DCs) after IMQ treatment, and decreased the levels of chemokines in keratinocytes treated with IL-17A by downregulating the expression of IL-17RA. RNA-seq and KEGG analysis revealed that L-THE significantly regulated the expression of IL-17A and NF-κB signaling pathway-associated genes. Metabolomics analysis displayed that L-THE promoted propanoate metabolism which has been reported to inhibit the activity of TH17 cells. Therefore, our results demonstrated that L-THE significantly decreases the levels of IL-23 and chemokines, and attenuates IMQ-induced psoriasis like skin inflammation by inhibiting the activation of NF‐κB and IL-17A signaling pathways, and promoting the propanoate metabolism. Our findings suggest that topical applied L-THE can be used as a topical drug candidate for the treatment of psoriasis or as an adjuvant treatment of ustekinumab or secukinumab to prevent the relapse of psoriasis.

Adipose mesenchymal stem cells combined with platelet-rich plasma accelerate diabetic wound healing by modulating the Notch pathway

Background Diabetic foot ulceration is a serious chronic complication of diabetes mellitus characterized by high disability, mortality, and morbidity. Platelet-rich plasma (PRP) has been widely used for diabetic wound healing due to its high content of growth factors. However, its application is limited due to the rapid degradation of growth factors. The present study aimed to evaluate the efficacy of combined adipose-derived mesenchymal stem cells (ADSCs) and PRP therapy in promoting diabetic wound healing in relation to the Notch signaling pathway. Methods Albino rats were allocated into 6 groups [control (unwounded), sham (wounded but non-diabetic), diabetic, PRP-treated, ADSC-treated, and PRP+ADSCs-treated groups]. The effect of individual and combined therapy was evaluated by assessing wound closure rate, epidermal thickness, dermal collagen, and angiogenesis. Moreover, gene and protein expression of key elements of the Notch signaling pathway (Notch1, Delta-like canonical Notch ligand 4 (DLL4), Hairy Enhancer of Split-1 (Hes1), Hey1, Jagged-1), gene expression of angiogenic marker (vascular endothelial growth factor and stromal cell-derived factor 1) and epidermal stem cells (EPSCs) related gene (ß1 Integrin) were assessed. Results Our data showed better wound healing of PRP+ADSCs compared to their individual use after 7 and 14 days as the combined therapy caused reepithelialization and granulation tissue formation with a marked increase in area percentage of collagen, epidermal thickness, and angiogenesis. Moreover, Notch signaling was significantly downregulated, and EPSC proliferation and recruitment were enhanced compared to other treated groups and diabetic groups. Conclusions These data demonstrated that PRP and ADSCs combined therapy significantly accelerated healing of diabetic wounds induced experimentally in rats via modulating the Notch pathway, promoting angiogenesis and EPSC proliferation.