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Alopecia areata (AA) is an autoimmune inflammatory disease characterized by non‐scarring hair loss due to an immune response that targets hair follicles. The current treatment approach for AA involves the use of immunosuppressants and immunomodulators to reduce cytokine levels around affected hair follicles. Sodium‐glucose cotransporter 2 (SGLT2) inhibitors have emerged as potential anti‐inflammatory agents with diverse beneficial effects in various medical conditions. This study investigates the role of beta‐hydroxybutyrate (BHB), a ketone body produced during SGLT2 inhibition, in the pathogenesis of AA. Serum BHB levels were found to be significantly elevated in patients with AA compared with healthy controls, with higher levels correlating with severity of hair loss. BHB treatment increased inflammatory cytokine production in outer root sheath (ORS) cells, mimicking the inflammatory conditions seen in AA. The results suggest that elevated BHB levels may exacerbate the inflammatory immune response in AA patients and may be associated with chronic hair loss and resistance to treatment. Serum BHB levels may serve as a potential marker of poor prognosis in patients with severe AA. Further research is needed to elucidate the precise role of BHB in the pathogenesis of AA and its implications for disease management. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic inflammatory skin disease characterized by epidermal hyperproliferation, aberrant differentiation of keratinocytes, and dysregulated immune responses. WW domain-containing oxidoreductase (WWOX) is a non-classical tumor suppressor gene that regulates multiple cellular processes, including proliferation, apoptosis, and migration. This study aimed to explore the possible role of WWOX in the pathogenesis of psoriasis. Immunohistochemical analysis showed that the expression of WWOX was increased in epidermal keratinocytes of both human psoriatic lesions and imiquimod-induced mice psoriatic model. Immortalized human epidermal keratinocytes were transduced with a recombinant adenovirus expressing microRNA specific for WWOX to downregulate its expression. Inflammatory responses were detected using Western blotting, real-time quantitative reverse transcription polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay. In human epidermal keratinocytes, WWOX knockdown reduced nuclear factor-kappa B signaling and levels of proinflammatory cytokines induced by polyinosinic: polycytidylic acid [(poly(I:C)] in vitro. Furthermore, calcium chelator and protein kinase C (PKC) inhibitors significantly reduced poly(I:C)-induced inflammatory reactions. WWOX plays a role in the inflammatory reaction of epidermal keratinocytes by regulating calcium and PKC signaling. Targeting WWOX could be a novel therapeutic approach for psoriasis in the future. [ABSTRACT FROM AUTHOR]

Alopecia areata (AA) is a T‐cell‐mediated autoimmune disease that causes chronic, relapsing hair loss; however, its precise pathogenesis remains to be elucidated. Recent studies have provided compelling evidence of crosstalk between inflammasomes and mitophagy—a process that contributes to the removal of damaged mitochondria. Our previous studies showed that the NLR family pyrin domain containing 3 (NLRP3) inflammasome is important for eliciting and progressing inflammation in AA. In this study, we detected mitochondrial DNA damage in AA‐affected scalp tissues and IFNγ and poly(I:C) treated outer root sheath (ORS) cells. In addition, IFNγ and poly(I:C) treatment increased mitochondrial reactive oxygen species (ROS) levels in ORS cells. Moreover, we showed that mitophagy induction alleviates IFNγ and poly(I:C)‐induced NLRP3 inflammasome activation in ORS cells. Lastly, PTEN‐induced kinase 1 (PINK1) knockdown increased NLRP3 inflammasome activation, indicating that PINK1‐mediated mitophagy plays a critical role in NLRP3 inflammasome activation in ORS cells. This study supports previous studies showing that oxidative stress disrupts immune privilege status and promotes autoimmunity in AA. The results emphasize the significance of crosstalk between mitophagy and inflammasomes in the pathogenesis of AA. Finally, mitophagy factors regulating mitochondrial dysfunction and inhibiting inflammasome activation could be novel therapeutic targets for AA. [ABSTRACT FROM AUTHOR]

Background: Dermal fibroblasts play a pivotal role in hair follicle regeneration during wound repair. Recently, dermal fibroblast‐conditioned medium (DFCM), which contains multi‐peptide factors (MPFs), has been used to promote wound repair. Aim: This study aimed to investigate the stimulatory effects of MPF‐containing DFCM on hair growth. Methods: MPF‐containing DFCM was prepared using human neonatal dermal fibroblasts. Outer root sheath (ORS) and dermal papilla (DP) cells were cultured in MPF‐containing DFCM. We examined the expression and secretion of growth factors and cytokines using quantitative polymerase chain reaction and a growth factor array. In addition, the effect of MPFs on β‐catenin activity was determined using the TOPflash assay. All experiments were repeated at least three times with separate batches of cells. Results: MPF‐containing DFCM increased keratinocyte growth factor (KGF), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) mRNA expression in ORS cells and KGF and VEGF mRNA expression in DP cells. When ORS cells were treated with MPF‐containing DFCM, the secretion of several growth factors, including EGF, VEGF, insulin‐like growth factor‐binding protein (IGFBP)‐4, IGFBP‐6, and fibroblast growth factor‐7, was increased in the cell‐cultured medium compared with that in control. Additionally, MPF‐containing DFCM increased the transcriptional activation of β‐catenin in DP cells. Conclusions: These results suggest that MPF‐containing DFCM might stimulate hair growth by inducing growth factors in ORS and DP cells and regulating β‐catenin in DP cells. [ABSTRACT FROM AUTHOR]

Keywords: acne; IGF-1; lipogenesis; sebocytes; YAP EN acne IGF-1 lipogenesis sebocytes YAP 996 998 3 07/14/23 20230701 NES 230701 Acne is a chronic inflammatory disorder of the pilosebaceous unit. From these results, we determined that IGF-1 increased YAP activity in sebocytes and YAP inhibition attenuated IGF-1-induced lipid production by preventing IGFR-mTOR signalling pathway. To investigate the mechanism of YAP inhibition on IGF-1-induced lipogenesis, we evaluated the protein expression of important transcription factors related to lipid production. [Extracted from the article]

Background: Dunnione has anti-inflammatory properties arising from its ability to alter the ratio of NAD+/NADH through NAD(P)H quinone oxidoreductase 1 (NQO1) enzymatic action, followed by subsequent inhibition of NF-κB and inflammatory cytokines. Psoriasis is a chronic, inflammatory skin disorder in which the IL-23/Th17 axis plays an important role in inflammation. However, it is unclear whether modulation of NAD+ levels affects psoriasis, such as skin inflammation. Therefore, in this study, we investigated the effect of NAD+/NADH ratio modulation on imiquimod (IMQ)-induced, psoriasis-like skin inflammation in mice. Methods: Psoriasis-like skin inflammation was generated by daily topical application of IMQ cream. The severity of dermatitis was assessed using the Psoriasis Area Severity Index (PASI) and histochemistry. Expression of inflammatory cytokines was detected by enzyme-linked immunosorbent assay and quantitative PCR. Acetylation of NF-κB p65 and STAT3 was determined by Western blotting. Results: Dunnione improved IMQ-induced epidermal hyperplasia and inflammation, consistent with decreased levels of inflammatory cytokines (IL-17, IL-22, and IL-23) in skin lesions. Moreover, we found that an increase in the NAD+/NADH ratio by dunnione restored SIRT1 activity, thereby reduced imiquimod-induced STAT3 acetylation, which modulates the expression of psoriasis-promoting inflammatory cytokines, such as IL-17, IL-22, and IL-23. Conclusion: Pharmacological modulation of cellular NAD+ levels could be a promising therapeutic approach for psoriasis-like skin disease. [ABSTRACT FROM AUTHOR]

We conducted large‐scale screening test on drugs that were already approved for other diseases to find pigmentation‐modulating agents. Among drugs with potential for pigmentation control, we selected sorafenib and further investigated the effect on pigmentation using HM3KO melanoma cells. As a result of treating melanoma cells with sorafenib, pigmentation was promoted in terms of melanin content and tyrosinase activity. Sorafenib increased mRNA and protein levels of pigmentation‐related genes such as MITF, tyrosinase and TRP1. To uncover the action mechanism, we investigated the effect of sorafenib on the intracellular signalling pathways. Sorafenib reduced phosphorylation of AKT and ERK, suggesting that sorafenib induces pigmentation through inhibition of the AKT and ERK pathways. In addition, sorafenib significantly increased the level of active β‐catenin, together with activation of β‐catenin signalling. Mechanistic study revealed that sorafenib decreased phosphorylation of serine 9 (S9) of GSK3β, while it increased phosphorylation of tyrosine 216 (Y216) of GSK3β. These results suggest that sorafenib activates the β‐catenin signalling through the regulation of GSK3β phosphorylation, thereby affecting the pigmentation process. [ABSTRACT FROM AUTHOR]