Higher Dietary Inflammatory Index and Increased Mortality Rate of Adults With Hyperuricemia: Findings From the National Health and Nutritional Examination Survey (2001-2018).

OBJECTIVE: This study aimed to assess the association between Dietary Inflammatory Index (DII) score and death among adults with hyperuricemia. METHODS: We collected data from the 2001 to 2018 cohorts of the National Health and Nutritional Examination Survey. Death information was obtained based on death certificate records from the National Death Index through December 31, 2019. The associations between DII score and all-cause, cardiovascular disease (CVD), and cancer death were investigated by using Cox proportional hazards regression models. RESULTS: We enrolled 7,786 participants with hyperuricemia in this study. The DII score ranged from -4.42 to 4.61. Higher DII score was significantly associated with higher levels of body mass index, glycohemoglobin, glucose, low-density lipoprotein-cholesterol, and C-reactive protein (all P < 0.05). During 67,851 person-years of follow-up, deaths of 1,456 participants were identified, including 532 CVD deaths and 246 cancer deaths. After adjusting for potential variables, significant higher risk of all-cause (hazard ratio [HR] 1.18, 95% confidence interval [95% CI] 1.03-1.36, P = 0.01) and CVD (HR 1.30, 95% CI 1.03-1.63, P = 0.02) death was observed for individuals with higher DII scores. Considering the DII score as a continuous variable, the risk of all-cause and CVD death increases 5% (HR 1.05, 95% CI 1.01-1.08) and 8% (HR 1.08, 95% CI 1.02-1.15) with each one-unit increment in DII score, respectively. Subgroup analysis indicated that the association between DII score and all-cause death among participants with hyperuricemia was more significant in males. CONCLUSION: DII score is found to be positively associated with all-cause and CVD death of adults with hyperuricemia. Controlling the intake of proinflammatory food might be a potential strategy to reduce the mortality rate.

Attenuation of fibroblast activation and fibrosis by adropin in systemic sclerosis.

Fibrotic diseases impose a major socioeconomic challenge on modern societies and have limited treatment options. Adropin, a peptide hormone encoded by the energy homeostasis-associated (ENHO) gene, is implicated in metabolism and vascular homeostasis, but its role in the pathogenesis of fibrosis remains enigmatic. Here, we used machine learning approaches in combination with functional in vitro and in vivo experiments to characterize adropin as a potential regulator involved in fibroblast activation and tissue fibrosis in systemic sclerosis (SSc). We demonstrated consistent down-regulation of adropin/ENHO in skin across multiple cohorts of patients with SSc. The prototypical profibrotic cytokine TGFß reduced adropin/ENHO expression in a JNK-dependent manner. Restoration of adropin signaling by therapeutic application of bioactive adropin34-76 peptides in turn inhibited TGFß-induced fibroblast activation and fibrotic tissue remodeling in primary human dermal fibroblasts, three-dimensional full-thickness skin equivalents, mouse models of bleomycin-induced pulmonary fibrosis and sclerodermatous chronic graft-versus-host-disease (sclGvHD), and precision-cut human skin slices. Knockdown of GPR19, an adropin receptor, abrogated the antifibrotic effects of adropin in fibroblasts. RNA-seq demonstrated that the antifibrotic effects of adropin34-76 were functionally linked to deactivation of GLI1-dependent profibrotic transcriptional networks, which was experimentally confirmed in vitro, in vivo, and ex vivo using cultured human dermal fibroblasts, a sclGvHD mouse model, and precision-cut human skin slices. ChIP-seq confirmed adropin34-76-induced changes in TGFß/GLI1 signaling. Our study characterizes the TGFß-induced down-regulation of adropin/ENHO expression as a potential pathomechanism of SSc as a prototypical systemic fibrotic disease that unleashes uncontrolled activation of profibrotic GLI1 signaling.

Ixekizumab for Active Radiographic Axial Spondyloarthritis in Chinese Patients: 16- and 52-Week Results from a Phase III, Randomized, Double-Blind, Placebo-Controlled Study.

INTRODUCTION: Ixekizumab, an interleukin-17A inhibitor, was efficacious and well tolerated for the treatment of active radiographic axial spondyloarthritis (r-axSpA) in international clinical studies. This phase III study aimed to determine the efficacy and safety of ixekizumab for treating Chinese patients with active r-axSpA. METHODS: Adults with active r-axSpA naïve to biologic disease-modifying antirheumatic drugs (bDMARDs), or with an inadequate response/intolerance to one tumor necrosis factor inhibitor, were randomized (1:1), double-blind, to receive ixekizumab 80 mg every 4 weeks (IXEQ4W; starting dose 160 mg), or placebo, for 16 weeks. Patients receiving placebo were then switched to IXEQ4W, and those receiving IXEQ4W continued, until week 52. The primary endpoint was the proportion of bDMARD-naïve patients achieving an Assessment of SpondyloArthritis International Society 40 (ASAS40) response at week 16. RESULTS: In total, 147 patients were randomized to receive placebo (n = 73) or IXEQ4W (n = 74). At week 16, more bDMARD-naive patients achieved ASAS40 in the IXEQ4W group (n = 66; 40.9%) than the placebo group (n = 64, 7.8%; p < 0.001). In the overall study population, ASAS40 was also achieved by more patients in the IXEQ4W group (37.8%) than the placebo group (8.2%; p < 0.001) at week 16, with a significant difference observed as early as week 1. There were significant improvements in all key secondary endpoints at week 16 with IXEQ4W versus placebo. Efficacy was sustained at week 52 in patients who continued IXEQ4W and there were also clinical improvements from weeks 16 to 52 in patients switched to IXEQ4W. The safety profile of ixekizumab was consistent with that described previously. Infections and injection-site reactions were the most frequently reported events of special interest. CONCLUSIONS: IXEQ4W was associated with rapid and significant improvements in the signs and symptoms of active r-axSpA in Chinese patients at week 16 that were sustained at week 52, with no new safety signals. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier: NCT04285229.

Progress in research on mesenchymal stem cells and their extracellular vesicles for treating fibrosis in systemic sclerosis.

Systemic sclerosis (SSc) refers to an autoimmune disease characterized by immune dysfunction, vascular endothelial damage, and multi-organ fibrosis. Thus far, this disease is incurable, and its high mortality rate is significantly correlated with fibrotic events. Fibrosis has been confirmed as a difficult clinical treatment area that should be urgently treated in clinical medicine. Mesenchymal stem cells (MSCs) exhibit immunomodulatory, pro-angiogenic, and anti-fibrotic functions. MSCs-derived extracellular vesicles (EVs) have aroused rising interest as a cellular component that retains the functions of MSCs while circumventing the possible adverse effects of MSCs. Moreover, EVs have great potential in treating SSc. In this study, the current research progress on MSCs and their EVs for treating fibrosis in SSc was reviewed, with an aim to provide some reference for future MSCs and their EVs in treating SSc.

B1-cell-produced anti-phosphatidylserine antibodies contribute to lupus nephritis development via TLR-mediated Syk activation.

Autoantibodies produced by B cells play a pivotal role in the pathogenesis of systemic lupus erythematosus (SLE). However, both the cellular source of antiphospholipid antibodies and their contributions to the development of lupus nephritis (LN) remain largely unclear. Here, we report a pathogenic role of anti-phosphatidylserine (PS) autoantibodies in the development of LN. Elevated serum PS-specific IgG levels were measured in model mice and SLE patients, especially in those with LN. PS-specific IgG accumulation was found in the kidney biopsies of LN patients. Both transfer of SLE PS-specific IgG and PS immunization triggered lupus-like glomerular immune complex deposition in recipient mice. ELISPOT analysis identified B1a cells as the main cell type that secretes PS-specific IgG in both lupus model mice and patients. Adoptive transfer of PS-specific B1a cells accelerated the PS-specific autoimmune response and renal damage in recipient lupus model mice, whereas depletion of B1a cells attenuated lupus progression. In culture, PS-specific B1a cells were significantly expanded upon treatment with chromatin components, while blockade of TLR signal cascades by DNase I digestion and inhibitory ODN 2088 or R406 treatment profoundly abrogated chromatin-induced PS-specific IgG secretion by lupus B1a cells. Thus, our study has demonstrated that the anti-PS autoantibodies produced by B1 cells contribute to lupus nephritis development. Our findings that blockade of the TLR/Syk signaling cascade inhibits PS-specific B1-cell expansion provide new insights into lupus pathogenesis and may facilitate the development of novel therapeutic targets for the treatment of LN in SLE.

Intestinal uric acid excretion contributes to serum uric acid decrease during acute gout attack.

OBJECTIVE: Spontaneous serum uric acid (SUA) decrease has been found in many patients during acute gout attacks, but its mechanism remains unclear. METHODS: The spontaneous regulation of SUA during a gout attack and its possible causes were evaluated in patients with gout. The mechanism of the spontaneous SUA decrease was further studied in Caco2 cells and a monosodium urate (MSU)-induced gout model of wild-type mice and ABCG2-/- mice. The urate transport function of intestinal epithelial cells was detected by transwell culture of Caco2 cells. Expression of ATP-binding cassette super-family G member 2 (ABCG2), IL-1ß and phosphoinositide 3-kinase (PI3K)/Akt was analysed using real-time PCR, western blotting, or immunofluorescence assays. RESULTS: SUA decreased during acute gout attacks in both the gout patients and MSU-induced gouty mice. Increased serum CRP and IL-1ß levels were correlated with the SUA decrease. Intestinal uric acid excretion and expression of ABCG2 were upregulated in the mice during acute gout attacks. In the ABCG2-/- mice, intestinal uric acid excretion significantly decreased during gout attacks. In an in vitro study of a transwell culture, ABCG2 and its upstream PI3K/Akt pathway were significantly upregulated in intestinal epithelial cells. However, ABCG2 expression and its associated intestinal uric acid transport were inhibited when PI3K/Akt was blocked by a PI3K inhibitor, LY294002. CONCLUSIONS: Increased intestinal urate excretion resulted in spontaneous SUA downregulation during acute gout attacks. Inflammation-induced PI3K/Akt activation and ABCG2 expression in epithelial cells might contribute to the upregulation of intestinal uric acid excretion.

L-shaped association between serum 25-hydroxyvitamin D and all-cause mortality of individuals with rheumatoid arthritis.

OBJECTIVE: We aimed to examine the relationship between serum 25-hydroxyvitamin D and all-cause, cause-specific mortality of patients with RA. METHODS: This cohort study included 1466 patients with RA from The National Health and Nutrition Examination Survey (NHANES) 2001-14. Mortality status was obtained according to death certificate records from the National Death Index. Cox proportional risk models were used to estimate hazard ratios (HR) and 95% CI for mortality. A generalized additive model, smooth curve fitting and 2-piecewise Cox proportional hazards models were established to address the nonlinearity between serum 25-hydroxyvitamin D and mortality. RESULTS: A total of 1466 patients [mean (s.d.) 59.89 (14.14) years old; 58.94% female] were enrolled. The weighted mean level of 25-hydroxyvitamin D was 59.26 (24.99) nmol/l and 38.95% were found with deficient (or severe deficient) vitamin D (<50.00 nmol/l). During 10453 person-years of follow-up, 268 patients were documented for all-cause death, including 52 cardiovascular disease （CVD）deaths and 48 cancer deaths. Compared with patients with serum 25-hydroxyvitamin D <25.00 nmol/l, patients with higher serum 25-hydroxyvitamin D were more likely to have lower rate of all-cause mortality. Nonlinear and L-shaped association between serum 25-hydroxyvitamin D and all-cause mortality was found, and decreased serum 25-hydroxyvitamin D was significantly associated with increased risk of all-cause mortality in patients with serum 25-hydroxyvitamin D <37.30 nmol/l [HR 0.95 (0.92, 0.98); P < 0.01]. CONCLUSION: An L-shaped association between serum 25-hydroxyvitamin D and all-cause mortality was found among patients with RA, indicating that serum 25-hydroxyvitamin D should be improved to a certain level for the prevention of premature death.

An ankylosing spondylitis risk variant alters osteoclast differentiation.

OBJECTIVE: To explore whether the variants in non MHC proteasome gene are associated with AS and explain the role of the variant in the disease. MATERIAL AND METHODS: Case-control analysis to identify AS predisposition genes; dual-luciferase reporter assay, immunoblot analysis and osteoclastogenesis assays to detect the function of the positive variant. Affected individuals were diagnosed according to the modified New York Criteria by at least two experienced rheumatologists, and rechecked by another rheumatologist. RESULTS: The study included 1037 AS patients and 1014 no rheumatic and arthritis disease controls. The main age of AS onset is between 16 and 35 years old. HLA-B27-positive subjects comprised 90.0% of patients. A nonsynonymous SNP rs12717 in proteasome gene PSMB1 significantly associated with AS. Individuals with CC genotype had a higher onset risk compared with those with GG/GC genotypes (OR = 1.89, P = 0.0047). We also discovered that PSMB1 regulates the receptor activator of nuclear factor-κB (RANK)/RANK ligand (RANKL) signalling pathway and the disease-associated variant PSMB1-Pro11 significantly inhibits RANKL-induced NF-κB pathway in osteoclast differentiation via the degradation of IKK-ß compared with PSMB1-Ala11. RANKL induced osteoclast differentiation was significantly lower in primary monocyte osteoclast precursor from individuals with genotype PSMB131C/31C compared with individuals with genotype PSMB131G/31G. CONCLUSIONS: These results reveal a novel understanding of the bone formation and reabsorbing imbalance in AS. The new bone formation phenotype can be attributed to the inhibition of osteoclast differentiation by a more functional PSMB1 gene.

Spontaneous tendon rupture in a patient with systemic sclerosis: a case report.

BACKGROUND: Systemic sclerosis (SSc) is an incurable autoimmune disease characterized by progressive skin fibrosis and organ failure. Tenosynovitis is a common musculoskeletal manifestation, but tendon rupture has seldom reported in SSc. CASE PRESENTATION: We present a rare case of a 49-year-old female with SSc who has suffered from bilateral tendon rupture of the fourth and fifth digits with positive antinuclear antibody (ANA) and anti-centromere B antibody, but negative rheumatoid factor in serum. In the extensor tendons of the patient's hands, inflammation, edema, hypertrophy and tendon interruption were detected with ultrasound and magnetic resonance imaging(MRI). Tendon transfer repair surgery was performed and 10 mg/week methotrexate was then used in this patient. Her hand function was improved well with methotrexate and rehabilitation treatment postoperatively. CONCLUSIONS: Early detection of tenosynovitis is necessary to prevent tendon rupture in SSc patients. Ultrasound and Magnetic Resonance Imaging appear to be useful examinations for evaluating tendon pathology for early detection.

Natural Adrenocorticotropic Hormone (ACTH) Relieves Acute Inflammation in Gout Patients by Changing the Function of Macrophages.

Gout is a common arthritis caused by deposition of monosodium urate crystals. Macrophage is crucial in the process of monosodium urate (MSU)-induced inflammation. Although it has been reported that adrenocorticotropic hormone (ACTH) in nature can be used to cure urarthritis, the mechanism concerning macrophage is still not clear. However, gout patients manifest other complications, such as hypertension, diabetes, chronic kidney disease, and hormone intolerance, which limit efficacy of some of these first-line drugs. Therefore, this study aims to explore how natural ACTH can alleviate urarthritis through functional changes in macrophage. We analyzed the variations in VAS pain scores of five patients, knowing the time of action and detecting the level of cortisol and ACTH in patients 24 hours after the application of ACTH. The effect of natural ACTH on joint inflammation and the level of cortisol in blood in the mouse model was evaluated by studies in vivo. In vitro studies, we evaluated the effect of natural ACTH on macrophages and revealed different functions of ACTH and dexamethasone on macrophages in the transcriptional level. In patients with acute gout, natural ACTH can quickly alleviate pain and does not affect the level of cortisol and ACTH. Natural ACTH is able to ease the swelling and inflammatory cell infiltration caused by arthritis, without changing the level of cortisol. Besides, natural ACTH in vitro can alleviate acute gouty inflammation by regulating phagocytosis and polarization of macrophage, which also exerts different effects on the transcription of some related genes. Natural ACTH is able to alleviate acute gouty inflammation by regulating macrophage, and this effect differs from that of dexamethasone at the transcriptional level.

Distinct macrophage polarization in acute and chronic gout.

Macrophage polarization mediates the development of inflammatory diseases. However, the polarization status at various stages of gout is not fully understood. Our study aimed to define the evolution of macrophage polarization in acute and chronic gout. Normal human synovium and synovium with tophi were collected for immunofluorescence (IF). Rat gouty joints were collected for joint thickness assessment and pathological evaluation. Tissue mRNA expression of inducible nitric oxide synthase (iNOS) and arginase-1 (Arg-1) were evaluated. Mouse peritoneal macrophages and THP-1 derived macrophages were stimulated by monosodium urate (MSU) crystals and were collected for detection of interleukin (IL) -1ß and IL-37 levels and iNOS/Arg-1 ratio. Arg-1 and IL-37 were highly expressed in normal synovium and synovium with tophi. In rat gouty joints, the inflammatory cell counts and ankle thickness began to increase at 2 h, peaked at 24 h, and was decreased spontaneously. An increase in macrophages preceded the neutrophils infiltration. Infiltration of M1 was positively related with the severity of arthritis. M2 appeared in an early stage (at 2 h) of inflammation. The number of M1 macrophages was comparable to that of M2 from 2 to 12 h and exceeded M2 number at 18 h and 24 h. The ratios of M2/M1 reversed at 48 h and remained reversed until 120 h. In mice gouty joints, iNOS/Arg-1 mRNA ratio was significantly higher than the that in control group at 8 h. The proportion of neutrophils and M1-macrophages reached peak at 4 h in mice model with peritoneal gout. Concentration of IL-1ß and ratio of iNOS/Arg-1 were increased at 6 h, peaked at 48 h, and were then decreased at 72 h in vitro, while the concentration of IL-37 peaked at 2 h and then decreased. In summary, altered macrophage polarization was observed in various stages of gouty inflammation. Macrophages in acute gout were polarized into M1 at early stage and into M2 at later stage while the macrophages in chronic gout mainly were only polarized towards M2. The number of M1 rose with the progression of inflammation. Early increase of M2 was observed, which might be generated directly from M0.

IL-37 blocks gouty inflammation by shaping macrophages into a non-inflammatory phagocytic phenotype.

OBJECTIVE: Interleukin (IL)-37 is a natural suppressor of inflammation. Macrophages play an important role in acute gout flare by dominating the inflammation and spontaneous relief. We have reported that IL-37 could limit runaway inflammation in gout. Here we focus on whether IL-37 inhibits gouty inflammation by altering macrophage functions, and how it does so. METHODS: Macrophage functions were evaluated in terms of phagocytosis, pyroptosis, polarization and metabolism. Phagocytosis and polarization of macrophages were detected by side scattering and double-labelling induced nitrogen monoxide synthase (iNOS)/arginase-1 (Arg-1) using flow cytometry, respectively. Transcription of pyroptosis-related molecules was detected by qPCR. Metabolomics was performed by liquid chromatograph mass spectrometer. Human IL-37 knock-in mice and a model with point mutation (S9A) at mouse Gsk3b locus were created by CRISPR/Cas-mediated genome engineering. MSU was injected into the paws and peritoneal cavity to model acute gout. Vernier calliper was used to measure the thickness of the paws. The mice paws and human synovium tissues or tophi were collected for pathological staining. Peritoneal fluid of mice was used to enrich macrophages to detect polarization. RESULTS: IL-37 promoted non-inflammatory phagocytic activity of macrophages by enhancing phagocytosis of MSU, reducing transcription of pyroptosis-related proteins and release of inflammatory cytokines, protecting mitochondrial function, and mediating metabolic reprogramming in MSU-treated THP-1 cells. These multifaceted roles of IL-37 were partly depended on the mediation of glycogen synthase kinase-3ß (GSK-3ß). CONCLUSIONS: Our study revealed that IL-37 could shape macrophages into a 'silent' non-inflammatory phagocytic fashion. IL-37 may become a potentially valuable treatment option for patients of chronic gout, especially for those with tophi.

B cell-activating factor and its targeted therapy in autoimmune diseases.

B cells play a pivotal role in the pathogenesis of autoimmune disease (AD) by the production of autoantibodies, secretion of cytokines and presentation of autoantigens. As a pro-survival factor mainly produced by myeloid cells, B cell-activating factor (BAFF) maintains B cell maturation and homeostasis at various B cell differentiation stages. Under autoimmune conditions, BAFF acts on autoreactive B cells that have escaped checkpoint apoptosis from negative selection. Numerous studies have shown increased levels of BAFF in patients with ADs and in mouse models with ADs wherein the production of autoantibodies is a prominent feature of immunopathology. Compelling evidence has indicated a key function of BAFF in driving autoreactive B cell response during autoimmune progression. Recent clinical studies have demonstrated BAFF as a therapeutic target in various ADs. Here, we review recent findings on BAFF expression and its effector mechanisms in autoimmune pathogenesis as well as newly developed therapeutic targeting of BAFF in the treatment of ADs.

The Multiple Roles of B Cells in the Pathogenesis of Sjögren's Syndrome.

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease characterized by lymphocytic infiltration and tissue destruction of exocrine glands such as salivary glands. Although the formation of ectopic lymphoid tissue in exocrine glands and overproduction of autoantibodies by autoreactive B cells highlight the critical involvement of B cells in disease development, the precise roles of various B cell subsets in pSS pathogenesis remain partially understood. Current studies have identified several novel B cell subsets with multiple functions in pSS, among which autoreactive age-associated B cells, and plasma cells with augmented autoantibody production contribute to the disease progression. In addition, tissue-resident Fc Receptor-Like 4 (FcRL4)+ B cell subset with enhanced pro-inflammatory cytokine production serves as a key driver in pSS patients with mucosa-associated lymphoid tissue (MALT)-lymphomas. Recently, regulatory B (Breg) cells with impaired immunosuppressive functions are found negatively correlated with T follicular helper (Tfh) cells in pSS patients. Further studies have revealed a pivotal role of Breg cells in constraining Tfh response in autoimmune pathogenesis. This review provides an overview of recent advances in the identification of pathogenic B cell subsets and Breg cells, as well as new development of B-cell targeted therapies in pSS patients.

IL-17 drives salivary gland dysfunction via inhibiting TRPC1-mediated calcium movement in Sjögren's syndrome.

OBJECTIVES: This study aims to determine a role of interleukin-17A (IL-17) in salivary gland (SG) dysfunction and therapeutic effects of targeting IL-17 in SG for treating autoimmune sialadenitis in primary Sjögren's syndrome (pSS). METHODS: Salivary IL-17 levels and IL-17-secreting cells in labial glands of pSS patients were examined. Kinetic changes of IL-17-producing cells in SG from mice with experimental Sjögren's syndrome (ESS) were analysed. To determine a role of IL-17 in salivary secretion, IL-17-deficient mice and constructed chimeric mice with IL-17 receptor C (IL-17RC) deficiency in non-hematopoietic and hematopoietic cells were examined for saliva flow rates during ESS development. Both human and murine primary SG epithelial cells were treated with IL-17 for measuring cholinergic activation-induced calcium movement. Moreover, SG functions were assessed in ESS mice with salivary retrograde cannulation of IL-17 neutralisation antibodies. RESULTS: Increased salivary IL-17 levels were negatively correlated with saliva flow rates in pSS patients. Both IL-17-deficient mice and chimeric mice with non-hematopoietic cell-restricted IL-17RC deficiency exhibited no obvious salivary reduction while chimeric mice with hematopoietic cell-restricted IL-17RC deficiency showed significantly decreased saliva secretion during ESS development. In SG epithelial cells, IL-17 inhibited acetylcholine-induced calcium movement and downregulated the expression of transient receptor potential canonical 1 via promoting Nfkbiz mRNA stabilisation. Moreover, local IL-17 neutralisation in SG markedly attenuated hyposalivation and ameliorated tissue inflammation in ESS mice. CONCLUSION: These findings identify a novel function of IL-17 in driving salivary dysfunction during pSS development and may provide a new therapeutic strategy for targeting SG dysfunction in pSS patients.

Melatonin Alleviates Acute Gouty Inflammation In Vivo and In Vitro.

The aim of this study was to identify the effects of melatonin on acute gouty inflammation and to investigate the underlying mechanisms. We found significantly lower serum melatonin levels in gout patients in the acute phase than in those in the remission phase or in normal individuals. The mRNA expression of melatonin receptor 2 (MT2) was also lower in gout patients than in normal individuals. To verify the in-vivo role of melatonin, a gouty arthritis model was established by intraarticular injection of monosodium urate (MSU, 1 mg) crystals into the paws of C57BL/6 mice. Joint inflammation in the mouse model was evaluated by measuring the thickness of the right paw/left paw, and the inflammation index was determined by examining infiltrating neutrophils with haematoxylin and eosin (H&E) staining. Melatonin was found to reduce both paw thickness and the inflammation index in the mouse model, and melatonin also reduced the mRNA levels of interleukin-1 beta (IL-1ß), IL-6 and NLR family pyrin domain containing 3 (NLRP3) inflammasome. To mimic gouty inflammation in vitro, mouse peritoneal macrophages were stimulated with lipopolysaccharides (LPS) plus MSU. Melatonin was revealed to reduce IL-1ß secretion by stimulated macrophages. The mRNA expression levels of IL-1ß and IL-6 were also inhibited by melatonin. Western blot analysis showed that the expression of NLRP3, caspase-1 and pro-IL-1ß was also inhibited by melatonin. In conclusion, our study demonstrated that melatonin alleviated gouty inflammation in vivo and in vitro, and the underlying mechanism may involve inhibiting the assembly of the NLRP3 inflammasome.

The Anti-Inflammatory and Uric Acid Lowering Effects of Si-Miao-San on Gout.

Background: Si-Miao-San (SMS) is a well-known traditional Chinese medicine. This study aims to evaluate the anti-inflammatory effects of SMS on gouty arthritis and its potential mechanism of action. Methods: The effects and mechanism of SMS were evaluated in monosodium urate (MSU)-treated mice or macrophages. The expression of cytokines and PI3K/Akt was analyzed using real-time PCR and Western blotting analyses. Macrophage polarization was assessed with immunofluorescence assays, real-time PCR, and Western blotting. Mass spectrometry was used to screen the active ingredients of SMS. Results: Pretreatment with SMS ameliorated MSU-induced acute gouty arthritis in mice with increased PI3K/Akt activation and M2 macrophage polarization in the joint tissues. In vitro, SMS treatment significantly inhibited MSU-triggered inflammatory response, increased p-Akt and Arg-1 expression in macrophages, and promoted M2 macrophage polarization. These effects of SMS were inhibited when PI3K/Akt activation was blocked by LY294002 in the macrophages. Moreover, SMS significantly reduced serum uric acid levels in the hyperuricemia mice. Using mass spectrometry, the plant hormones ecdysone and estrone were detected as the potentially effective ingredients of SMS. Conclusion: SMS ameliorated MSU-induced gouty arthritis and inhibited hyperuricemia. The anti-inflammatory mechanism of SMS may exert anti-inflammatory effects by promoting M2 polarization via PI3K/Akt signaling. Ecdysone and estrone might be the potentially effective ingredients of SMS. This research may provide evidence for the application of SMS in the treatment of gout.

Ultrasound assessment of skin thickness and stiffness: the correlation with histology and clinical score in systemic sclerosis.

BACKGROUND: Ultrasound is a useful tool to evaluate and quantify skin lesions. Few studies have assessed the criterion validity of skin ultrasound in systemic sclerosis (SSc). The aims of the study were to investigate skin thickness and stiffness using ultrasound and shear wave elastography (SWE) in SSc and to validate skin ultrasound measurements against histological skin thickness. METHODS: A total of 22 patients with diffuse cutaneous SSc (dcSSc), 22 with limited cutaneous SSc (lcSSc), and 22 age- and gender-matched healthy controls were enrolled. Skin thickness and stiffness were measured by B-mode ultrasound with SWE imaging on the bilateral fingers and hands. Additional ultrasound evaluation was carried out in 13 patients (9 dcSSc and 4 lcSSc) on their dorsal forearms, followed by skin biopsy conducted in the same skin areas. Correlations between ultrasound measurements and histological skin thickness and modified Rodnan skin score (mRSS) were investigated using Spearman's correlation. RESULTS: Compared with controls, ultrasound-measured skin thickness and skin stiffness were significantly higher in patients with SSc (p < 0.001) and even higher in those with dcSSc. No clear correlation could be established between ultrasound-determined skin thickness and stiffness at the same site. Ultrasound-measured skin thickness correlated well with histological skin thickness (r = 0.6926, p = 0.009). A weaker association was also observed between histological skin thickness and local mRSS (r = 0.5867, p = 0.050). CONCLUSIONS: Ultrasound is a reliable tool for quantifying skin involvement in SSc. Ultrasound-measured skin thickness showed good agreement with histological skin thickness.

The IgG galactosylation ratio is higher in spondyloarthritis patients and associated with the MRI score.

OBJECTIVES: MRI is an important tool for evaluating inflammation levels and assessing treatment response in patients with ankylosing spondylitis (AS). However, it is expensive and requires experienced physicians. The goal of this study was to identify a biomarker correlated with the MRI score. METHODS: A total of 558 spondyloarthritis (SpA) patients including 527 AS patients, 10 psoriasis (PsA) patients, and 21 non-radiographic SpA (nr-SpA) patients and 725 controls were enrolled for the studies. Plasma IgG galactosylation (IgG-Gal) level was measured by mass spectrometry. Clinical indexes such as Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and C-reactive protein (CRP) were measured in all AS patients. MRIs and X-rays were obtained from 65 AS patients who were followed up for 6 months. RESULTS: The IgG-Gal ratio was twice as high in the AS patients compared with the controls. It correlated with inflammation indices which is evaluated by MRI according to SPARCC. (Pearson coefficient/p value was 0.6/7E10-6). In addition, AS patients with a higher IgG-Gal ratio at baseline tended to show greater improvement in inflammation scores by MRI both in 3-month follow-up and 6-month follow-up. CONCLUSION: The IgG-Gal ratio was significantly increased in AS patients. In clinical care, it may be used as a potential biomarker for diagnosis in the future. Key Points • IgG galactosylation level was abnormal in SpA patients. • IgG galactosylation level was associated with MRI indices.

Cardiovascular events in hyperuricemia population and a cardiovascular benefit-risk assessment of urate-lowering therapies: a systematic review and meta-analysis.

BACKGROUND: Hyperuricemia and gout have become public health concerns; many important guidelines have recommended xanthine oxidase inhibitors (XOIs) as the first-line urate-lowering therapies (ULTs) to treat chronic gout with hyperuricemia. However, whether treating hyperuricemia and gout with ULTs modifies cardiovascular risks remains controversial. The aim of this study was to assess the incident risk of cardiovascular (CV) events (CVE) in hyperuricemia population, assess the cardiovascular benefit-risk of ULTs in hyperuricemia patients with or without gout in diverse cardiovascular risk sub-groups, and specify the safety of different ULTs. METHODS: We searched PubMed, Embase, the Cochrane Library, Wanfang, Chongqing VIP (CQVIP, en.cqvip.com), and China National Knowledge Infrastructure Database for prospective cohort studies and randomized controlled trials (RCTs) in English and Chinese. Potential medications included XOIs, and uricosurics. RCTs were divided into sub-groups analysis based on blinding status and patients' history of CV diseases. Risk ratios (RRs) were calculated and were reported with corresponding 95% confidence intervals (CIs) by fixed-effects or random-effects model. RESULTS: Seven prospective cohort studies and 17 RCT studies were included. The risks of both major adverse cardiovascular events (MACE) (RR = 1.72, 95% CI 1.28-2.33) and CVE (RR = 1.35, 95% CI 1.12-1.62) were higher in the hyperuricemia population than non-hyperuricemia one. In seven RCT studies where XOIs were compared with no-treatment or placebo, the results of five low CV risk studies showed that XOIs lowered the risks of both MACE (RR = 0.35, 95% CI 0.20-0.62) and CVE (RR = 0.61, 95% CI 0.44-0.85); whereas two high CV risk studies showed that XOIs lowered the risk of CVE (RR = 0.69, 95% CI 0.54-0.88) rather than MACE (RR = 0.62, 95% CI 0.29-1.35). In nine RCT studies where the cardiovascular safety between febuxostat and allopurinol were compared, no statistical difference was found in the risk of MACE or CVE. CONCLUSIONS: The hyperuricemia population does have a higher incidence of CVE, and the results suggested that XOIs might reduce the incidence of MACE and total CVE. In addition, from the perspective of cardiovascular safety, febuxostat equaled allopurinol in our meta-analysis.