Possible role of ß-hydroxybutyrate in inducing inflammation in alopecia areata.

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.

Efficacy and safety of topical corticosteroid treatment under occlusion for severe alopecia areata in children: a single-centre retrospective analysis.

BACKGROUND: Alopecia areata (AA) has a poor clinical course in children. There are no reliable therapeutic options for children with severe AA, including alopecia totalis (AT) and alopecia universalis (AU). OBJECTIVES: We evaluated the efficacy and adverse effects of a potent topical corticosteroid (TCS) under occlusion in paediatric patients with severe AA. METHODS: We reviewed records of 23 patients under the age of 10 years with AT or AU treated with a potent TCS (0.05% clobetasol propionate or 0.3% diflucortolone valerate) for 8 h under occlusion with a plastic film. We used the Severity of Alopecia Tool (SALT) to measure clinical improvement. The primary endpoint was a SALT score of ≤ 20 at 6 months. We analysed the change in cortisol levels to identify the long-term safety of TCS therapy on the hypothalamus-pituitary-adrenal axis. RESULTS: Nineteen of the 23 patients (83%) reached SALT ≤ 20 at 6 months. Six patients relapsed over the 6-month follow-up period. Four patients were suspected of having adrenal insufficiency. However, the cortisol levels of the patients recovered to normal within 1 month of lowering the TCS potency or changing to nonsteroidal treatments. Limitations include the retrospective design and small sample size. CONCLUSIONS: This study shows that a potent TCS occlusion may be a safe treatment option in paediatric patients with severe AA. Further long-term studies are required to evaluate the safety and recurrence of TCS occlusion therapy for paediatric AA.

The crosstalk between PTEN-induced kinase 1-mediated mitophagy and the inflammasome in the pathogenesis of alopecia areata.

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.

Disease-microenvironment modulation by bare- or engineered-exosome for rheumatoid arthritis treatment.

BACKGROUND: Exosomes are extracellular vesicles secreted by eukaryotic cells and have been extensively studied for their surface markers and internal cargo with unique functions. A deeper understanding of exosomes has allowed their application in various research areas, particularly in diagnostics and therapy. MAIN BODY: Exosomes have great potential as biomarkers and delivery vehicles for encapsulating therapeutic cargo. However, the limitations of bare exosomes, such as rapid phagocytic clearance and non-specific biodistribution after injection, pose significant challenges to their application as drug delivery systems. This review focuses on exosome-based drug delivery for treating rheumatoid arthritis, emphasizing pre/post-engineering approaches to overcome these challenges. CONCLUSION: This review will serve as an essential resource for future studies to develop novel exosome-based therapeutic approaches for rheumatoid arthritis. Overall, the review highlights the potential of exosomes as a promising therapeutic approach for rheumatoid arthritis treatment.

A preliminary study about the potential risks of the UV-weathered microplastic: The proteome-level changes in the brain in response to polystyrene derived weathered microplastics.

The growing use of plastic materials has resulted in a constant increase in the risk associated with microplastics (MPs). Ultra-violet (UV) light and wind break down modify MPs in the environment into smaller particles known as weathered MPs (WMPs) and these processes increase the risk of MP toxicity. The neurotoxicity of weathered polystyrene-MPs remains unclear. Therefore, it is important to understand the risks posed by WMPs. We evaluated the chemical changes of WMPs generated under laboratory-synchronized environmentally mimetic conditions and compared them with virgin MPs (VMPs). We found that WMP had a rough surface, slight yellow color, reduced molecular weight, and structural alteration compared with those of VMP. Next, 2 µg of ∼100 µm in size of WMP and VMP were orally administered once a day for one week to C57BL/6 male mice. Proteomic analysis revealed that the WMP group had significantly increased activation of immune and neurodegeneration-related pathways compared with that of the VMP group. Consistently, in in vitro experiments, the human brain-derived microglial cell line (HMC-3) also exhibited a more severe inflammatory response to WMP than to VMP. These results show that WMP is a more profound inflammatory factor than VMP. In summary, our findings demonstrate the toxicity of WMPs and provide theoretical insights into their potential risks to biological systems and even humans in the ecosystem.

SIRT1 downregulation provokes immune-inflammatory responses in hair follicle outer root sheath cells and may contribute to development of alopecia areata.

BACKGROUND: Silent information regulator 1 (SIRT1), a type III histone deacetylase, is involved in various cutaneous and systemic autoimmune diseases including systemic lupus erythematosus, rheumatoid arthritis, and psoriasis. However, little is known about the role of SIRT1 in the development of alopecia areata (AA). OBJECTIVES: This study investigated whether SIRT1 regulates the hair follicle immune system and is involved in AA pathogenesis. METHODS: SIRT1 expression in human scalp tissue was analyzed using immunohistochemical staining, qPCR, and western blotting. The regulatory effect of SIRT1 was evaluated after stimulation with the double-stranded RNA mimic polyinosinic:polycytidylic acid (poly I:C) in hair follicle outer root sheath (ORS) cells and C3H/HeJ mice. RESULTS: SIRT1 expression was significantly reduced in the AA scalp compared to the normal scalp. SIRT1 inhibition upregulated MHC class I polypeptide-related sequence A and UL16 binding protein 3 in hair follicle ORS cells. SIRT1 inhibition also promoted the production of Th1 cytokines (IFN-γ and TNF-α), IFN-inducible chemokines (CXCL9 and CXCL10), and T cell migration in ORS cells. Conversely, SIRT1 activation suppressed the autoreactive inflammatory responses. The counteractive effect of the immune response by SIRT1 was mediated through the deacetylation of NF-κB and phosphorylation of STAT3. CONCLUSION: SIRT1 downregulation induces immune-inflammatory responses in hair follicle ORS cells and may contribute to AA development.

Higher Genetic Risk Loads Confer More Diverse Manifestations and Higher Risk of Lupus Nephritis in Systemic Lupus Erythematosus.

OBJECTIVE: Systemic lupus erythematosus (SLE) is a highly heritable complex disorder with heterogeneous clinical manifestations. In this study, we aimed to identify the genetic risk load using clinical and serological manifestations in SLE patients. METHODS: We genotyped a total of 1,655 Korean patients with SLE (n = 1,243 as a discovery set and n = 412 as a replication set) using a customized genome-wide single-nucleotide polymorphism (SNP) array, KoreanChip. A weighted genetic risk score (wGRS) for an individual was calculated from 112 well-validated non-HLA SNPs and HLA haplotypes of SLE-risk loci. We analyzed associations between individual wGRS and clinical SLE subphenotypes and autoantibodies using multivariable linear or logistic regression adjusted by onset age, sex, and disease duration. RESULTS: Childhood-onset SLE (<16 years) conferred the highest genetic risk compared with adult-onset (16-50 years) or late-onset (>50 years) SLE (P = 6.8 × 10-6 ). High wGRS significantly increased associations with SLE manifestations, regardless of onset age, sex, and disease duration. Individual wGRS significantly correlated positively with more clinical American College of Rheumatology criteria (ß = 0.143, P = 1.8 × 10-6 ). Subphenotype analysis revealed significant associations between the highest and lowest wGRS quartile with risk of renal disorder (hazard ratio [HR] 1.74, P = 2.2 × 10-8 ) and anti-Sm antibody production (HR 1.85, P = 2.8 × 10-5 ). Higher wGRS markedly modulated the pathogenesis of proliferative and membranous lupus nephritis class III or IV (HR 1.98, P = 1.6 × 10-5 ) and class V (HR 2.79, P = 1.0 × 10-3 ), but especially lupus nephritis class V in anti-Sm-positive SLE (area under the curve 0.68, P = 1.8 × 10-4 ). CONCLUSION: Patients with SLE and high wGRS tended to have earlier age of SLE onset, higher anti-Sm antibody positivity, and more diverse clinical phenotypes. Genetic profiling may predict high risk for lupus nephritis and a diverse clinical course in SLE patients.

Curvature-sensing peptide inhibits tumour-derived exosomes for enhanced cancer immunotherapy.

Tumour-derived exosomes (T-EXOs) impede immune checkpoint blockade therapies, motivating pharmacological efforts to inhibit them. Inspired by how antiviral curvature-sensing peptides disrupt membrane-enveloped virus particles in the exosome size range, we devised a broadly useful strategy that repurposes an engineered antiviral peptide to disrupt membrane-enveloped T-EXOs for synergistic cancer immunotherapy. The membrane-targeting peptide inhibits T-EXOs from various cancer types and exhibits pH-enhanced membrane disruption relevant to the tumour microenvironment. The combination of T-EXO-disrupting peptide and programmed cell death protein-1 antibody-based immune checkpoint blockade therapy improves treatment outcomes in tumour-bearing mice. Peptide-mediated disruption of T-EXOs not only reduces levels of circulating exosomal programmed death-ligand 1, but also restores CD8+ T cell effector function, prevents premetastatic niche formation and reshapes the tumour microenvironment in vivo. Our findings demonstrate that peptide-induced T-EXO depletion can enhance cancer immunotherapy and support the potential of peptide engineering for exosome-targeting applications.

Mechanistic Investigation of WWOX Function in NF-kB-Induced Skin Inflammation in Psoriasis.

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.

Health information use by patients with systemic lupus erythematosus (SLE) pre and during the COVID-19 pandemic.

OBJECTIVE: We conducted an international survey of patients with SLE to assess their access, preference and trust in various health information sources pre-COVID-19 and during the COVID-19 pandemic. METHODS: Patients with SLE were recruited from 18 observational cohorts, and patients self-reporting SLE were recruited through five advocacy organisations. Respondents completed an online survey from June 2020 to December 2021 regarding the sources of health information they accessed in the 12 months preceding (pre-11 March 2020) and during (post-11 March 2020) the pandemic. Multivariable logistic regressions assessed factors associated with accessing news and social media post-11 March 2020, and self-reporting negative impacts from health information accessed through these sources. RESULTS: Surveys were completed by 2111 respondents; 92.8% were female, 76.6% had postsecondary education, mean (SD) age was 48.8 (14.0) years. Lupus specialists and family physicians were the most preferred sources pre-11 March 2020 and post-11 March 2020, yet were accessed less frequently (specialists: 78.5% pre vs 70.2% post, difference -8.3%, 95% CI -10.2% to -6.5%; family physicians: 57.1% pre vs 50.0% post, difference -7.1%, 95% CI -9.2% to -5.0%), while news (53.2% pre vs 62.1% post, difference 8.9%, 95% CI 6.7% to 11.0%) and social media (38.2% pre vs 40.6% post, difference 2.4%, 95% CI 0.7% to 4.2%) were accessed more frequently post-11 March 2020 vs pre-11 March 2020. 17.2% of respondents reported negative impacts from information accessed through news/social media. Those outside Canada, older respondents or with postsecondary education were more likely to access news media. Those in Asia, Latin America or younger respondents were more likely to access social media. Those in Asia, older respondents, males or with postsecondary education in Canada, Asia or the USA were less likely to be negatively impacted. CONCLUSIONS: Physicians, the most preferred and trusted sources, were accessed less frequently, while news and social media, less trusted sources, were accessed more frequently post-11 March 2020 vs pre-11 March 2020. Increasing accessibility to physicians, in person and virtually, may help reduce the consequences of accessing misinformation/disinformation.

Natural-Product-Inspired Approaches for Cancer Diagnosis and Therapy.

In recent years, new methods of cancer diagnosis and therapy have emerged as promising options for fighting cancer [...].

Role of Substance P in Regulating Micro-Milieu of Inflammation in Alopecia Areata.

BACKGROUND: Alopecia areata (AA) is an autoimmune disease characterized by chronic inflammation, the pathogenesis of which is unknown. Stress is believed to play a role; however, evidence remains insufficient. A recent study showed that substance P (SP) damaged hair follicles by causing neurogenic inflammation, activating perifollicular mast cells, and inducing keratinocyte apoptosis. OBJECTIVE: We aimed at studying the role of SP in AA pathogenesis. We investigated the SP levels in the lesional scalp tissues and serum. We also studied the effect of SP on the inflammatory response and hair growth in the outer root sheath (ORS) cells. METHODS: We compared the serum levels of SP in 58 AA patients and 28 healthy subjects. Then, we checked the expression of SP and SP receptor, neurokinin-1 receptor (NK-1R) in the scalps of AA patients and healthy controls using immunohistochemical staining. Finally, we analyzed the mRNA expression of inflammatory cytokines and hair growth-related factors in ORS cells. RESULTS: SP and NK-1R expression were markedly higher in the hair follicles and interfollicular epidermis of the scalp lesions of AA patients. However, there was no statistically significant difference in serum SP levels between controls and patients, regardless of the type of alopecia. SP significantly increased the mRNA expression of inflammatory cytokines and decreased hair growth-related growth factors in ORS cells, but the results were not dramatic. CONCLUSION: SP triggered a localized micro-inflammation in lesional hair follicles, provoked an inflammatory response, and inhibited hair growth, thereby confirming the pathogenic role of SP in AA.

The potential role of fibroblast-derived multi-peptide factors in activation of growth factors and ß-Catenin in hair follicle cells.

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 ß-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 ß-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 ß-catenin in DP cells.

Biological insights into systemic lupus erythematosus through an immune cell-specific transcriptome-wide association study.

OBJECTIVE: Genome-wide association studies (GWAS) have identified >100 risk loci for systemic lupus erythematosus (SLE), but the disease genes at most loci remain unclear, hampering translation of these genetic discoveries. We aimed to prioritise genes underlying the 110 SLE loci that were identified in the latest East Asian GWAS meta-analysis. METHODS: We built gene expression predictive models in blood B cells, CD4+ and CD8+ T cells, monocytes, natural killer cells and peripheral blood cells of 105 Japanese individuals. We performed a transcriptome-wide association study (TWAS) using data from the latest genome-wide association meta-analysis of 208 370 East Asians and searched for candidate genes using TWAS and three data-driven computational approaches. RESULTS: TWAS identified 171 genes for SLE (p<1.0×10-5); 114 (66.7%) showed significance only in a single cell type; 127 (74.3%) were in SLE GWAS loci. TWAS identified a strong association between CD83 and SLE (p<7.7×10-8). Meta-analysis of genetic associations in the existing 208 370 East Asian and additional 1498 cases and 3330 controls found a novel single-variant association at rs72836542 (OR=1.11, p=4.5×10-9) around CD83. For the 110 SLE loci, we identified 276 gene candidates, including 104 genes at recently-identified SLE novel loci. We demonstrated in vitro that putative causal variant rs61759532 exhibited an allele-specific regulatory effect on ACAP1, and that presence of the SLE risk allele decreased ACAP1 expression. CONCLUSIONS: Cell-level TWAS in six types of immune cells complemented SLE gene discovery and guided the identification of novel genetic associations. The gene findings shed biological insights into SLE genetic associations.

PD-L1 siRNA-hyaluronic acid conjugate for dual-targeted cancer immunotherapy.

"Foreignization" of tumor cells via delivery of a non-self foreign antigen (Ag) into tumors is an appealing strategy to initiate anti-tumor immunity that can facilitate tumor rejection by pre-existing foreign-Ag-reactive T cells. However, the immune-suppressive factors in the tumor microenvironment (TME) limit the durable and potent immune response of these cells against tumor antigens, stressing the need for improved tumor-foreignization strategies. Here, we demonstrate that blockade of programmed cell death ligand 1 (PD-L1) on both tumor cells and dendritic cells (DCs) can markedly potentiate the induction of tumor-reactive T cells, thereby strengthening the anti-tumor immunity ignited by tumor-foreignization. Specifically, we developed a polymeric nanoconjugate (PEG-HA-OVA/PPLs), consisting of siPD-L1-based polyplexes, PEGylated hyaluronic acid as the CD44-targeting moiety, and ovalbumin (OVA) as a model foreign antigen. Notably, PEG-HA-OVA/PPLs were simultaneously delivered into CD44high tumor cells and CD44high DCs, leading to efficient cross-presentation of OVA and downregulation of PD-L1 in both cell types. Importantly, the nanoconjugate not only allowed OVA-specific T cells to vigorously reject the foreignized tumor cells but also reprogrammed the TME to elicit robust T-cell responses specific to the endogenous tumor Ags, eventually generating long-lasting protective immunity. Thus, our combination strategy represents an innovative approach for the induction of potent tumor immunity via a two-step consecutive immune boost against exogenous and endogenous tumor Ags.

Recruitment of dendritic cells using 'find-me' signaling microparticles for personalized cancer immunotherapy.

Therapeutic cancer vaccines have attracted attention because of their potential to prime cytotoxic T cells, which are highly antigen (Ag)-specific, allowing personalized cancer immunotherapy. However, because of their low immunogenicity, cancer vaccines have been used in only a few types of cancers in clinics, primarily because of the poor Ag presentation of dendritic cells (DCs). To address these limitations of cancer vaccines, we show that 'find-me' signaling polymeric microparticles (F-PMs) bearing tumor lysate as an Ag can efficiently recruit DCs and facilitate antigen presentation. When subcutaneously injected into tumor-bearing mice, F-PMs significantly increased mature DCs in tumor-draining lymph nodes by eliciting adenosine triphosphate (ATP)-induced chemotaxis, resulting in high antitumor efficacy. CD8+ cytotoxic T cells were remarkably enriched in the tumor microenvironment following co-administration of an immune checkpoint inhibitor with F-PMs. We demonstrated that F-PMs elicit a robust antitumor immune response, which may provide a promising therapeutic option for cancer treatment.

Sulfisoxazole Elicits Robust Antitumour Immune Response Along with Immune Checkpoint Therapy by Inhibiting Exosomal PD-L1.

Despite their potent antitumor activity, clinical application of immune checkpoint inhibitors has been significantly limited by their poor response rates (<30%) in cancer patients, primarily due to immunosuppressive tumor microenvironments. As a representative immune escape mechanism, cancer-derived exosomes have recently been demonstrated to exhaust CD8+ cytotoxic T cells. Here, it is reported that sulfisoxazole, a sulfonamide antibacterial, significantly decreases the exosomal PD-L1 level in blood when orally administered to the tumor-bearing mice. Consequently, sulfisoxazole effectively reinvigorates exhausted T cells, thereby eliciting robust antitumor effects in combination with anti-PD-1 antibody. Overall, sulfisoxazole regulates immunosuppression through the inhibition of exosomal PD-L1, implying its potential to improve the response rate of anti-PD-1 antibodies.