Advanced glycation end products (AGEs) are generated by nonenzymatic modifications of macromolecules (proteins, lipids, and nucleic acids) by saccharides (glucose, fructose, and pentose) via Maillard ...reaction. The formed AGE molecules can be catabolized and cleared by glyoxalase I and II in renal proximal tubular cells. AGE-related diseases include physiological aging, neurodegenerative/neuroinflammatory diseases, diabetes mellitus (DM) and its complications, autoimmune/rheumatic inflammatory diseases, bone-degenerative diseases, and chronic renal diseases. AGEs, by binding to receptors for AGE (RAGEs), alter innate and adaptive immune responses to induce inflammation and immunosuppression via the generation of proinflammatory cytokines, reactive oxygen species (ROS), and reactive nitrogen intermediates (RNI). These pathological molecules cause vascular endothelial/smooth muscular/connective tissue-cell and renal mesangial/endothelial/podocytic-cell damage in AGE-related diseases. In the present review, we first focus on the cellular and molecular bases of AGE-RAGE axis signaling pathways in AGE-related diseases. Then, we discuss in detail the modes of action of newly discovered novel biomolecules and phytochemical compounds, such as Maillard reaction and AGE-RAGE signaling inhibitors. These molecules are expected to become the new therapeutic strategies for patients with AGE-related diseases in addition to the traditional hypoglycemic and anti-hypertensive agents. We particularly emphasize the importance of "metabolic memory", the "French paradox", and the pharmacokinetics and therapeutic dosing of the effective natural compounds associated with pharmacogenetics in the treatment of AGE-related diseases. Lastly, we propose prospective investigations for solving the enigmas in AGE-mediated pathological effects.
Gout is an inflammatory disease manifested by the deposition of monosodium urate (MSU) crystals in joints, cartilage, synovial bursa, tendons or soft tissues. Gout is not a new disease, which was ...first documented nearly 5,000 years ago. The prevalence of gout has increased globally in recent years, imposing great disease burden worldwide. Moreover, gout or hyperuricemia is clearly associated with a variety of comorbidities, including cardiovascular diseases, chronic kidney disease, urolithiasis, metabolic syndrome, diabetes mellitus, thyroid dysfunction, and psoriasis. To prevent acute arthritis attacks and complications, earlier use of pharmacotherapeutic treatment should be considered, and patients with hyperuricemia and previous episodes of acute gouty arthritis should receive long‐term urate‐lowering treatment. Urate‐lowering drugs should be used during the inter‐critical and chronic stages to prevent recurrent gout attacks, which may elicit gradual resolution of tophi. The goal of urate‐lowering therapy should aim to maintain serum uric acid (sUA) level <6.0 mg/dL. For patients with tophi, the initial goal can be set at lowering sUA to <5.0 mg/dL to promote tophi dissolution. The goal of this consensus paper was to improve gout and hyperuricemia management at a more comprehensive level. The content of this consensus paper was developed based on local epidemiology and current clinical practice, as well as consensuses from two multidisciplinary meetings and recommendations from Taiwan Guideline for the Management of Gout and Hyperuricemia.
Lupus nephritis (LN) is one of the most severe complications in patients with systemic lupus erythematosus (SLE). Traditionally, LN is regarded as an immune complex (IC) deposition disease led by ...dsDNA-anti-dsDNA-complement interactions in the subendothelial and/or subepithelial basement membrane of glomeruli to cause inflammation. The activated complements in the IC act as chemoattractants to chemically attract both innate and adaptive immune cells to the kidney tissues, causing inflammatory reactions. However, recent investigations have unveiled that not only the infiltrating immune-related cells, but resident kidney cells, including glomerular mesangial cells, podocytes, macrophage-like cells, tubular epithelial cells and endothelial cells, may also actively participate in the inflammatory and immunological reactions in the kidney. Furthermore, the adaptive immune cells that are infiltrated are genetically restricted to autoimmune predilection. The autoantibodies commonly found in SLE, including anti-dsDNA, are cross-reacting with not only a broad spectrum of chromatin substances, but also extracellular matrix components, including α-actinin, annexin II, laminin, collagen III and IV, and heparan sulfate proteoglycan. Besides, the glycosylation on the Fab portion of IgG anti-dsDNA antibodies can also affect the pathogenic properties of the autoantibodies in that α-2,6-sialylation alleviates, whereas fucosylation aggravates their nephritogenic activity. Some of the coexisting autoantibodies, including anti-cardiolipin, anti-C1q, anti-ribosomal P autoantibodies, may also enhance the pathogenic role of anti-dsDNA antibodies. In clinical practice, the identification of useful biomarkers for diagnosing, monitoring, and following up on LN is quite important for its treatments. The development of a more specific therapeutic strategy to target the pathogenic factors of LN is also critical. We will discuss these issues in detail in the present article.
To investigate the clinical outcomes and risk factors associated with progressive fibrosing interstitial lung disease (PF-ILD) in patients with primary Sjögren's syndrome-associated interstitial lung ...disease (pSjS-ILD).
During 2015-2021, pSjS patients with ILD were retrospectively identified. Patients were grouped into non-PF-ILD and PF-ILD. Demographics, laboratory data, pulmonary function tests (PFTs), images, survival outcomes were compared between groups.
153 patients with SjS-ILD were reviewed, of whom 68 having primary SjS-ILD (pSjS-ILD) were classified into non-PF-ILD (n = 34) and PF-ILD groups (n = 34). PF-ILD group had persistently lower albumin levels and a smaller decline in immunoglobulin G (IgG) levels at the 3rd month of follow-up. The multivariate logistic regression analysis revealed that persistently low albumin levels were associated with PF-ILD. At the 12th month, the PF-ILD group experienced a smaller increase in FVC and a greater decline in the diffusion capacity of carbon monoxide (DLCO) than at baseline. The 3-year overall survival rate was 91.2%, and PF-ILD group had significantly poorer 3-year overall survival rate than non-PF-ILD group (82.4% vs. 100%, p = 0.011). Poor survival was also observed among female patients with PF-ILD.
Among patients with pSjS-ILD, the PF-ILD group had poorer 3-year survival outcomes. Persistent lower albumin level might be the risk factor of PF-ILD. Early lung function tests could be helpful for the early detection of PF-ILD.
Sensory neuropathy is a prominent component of diabetic neuropathy. It is not entirely clear how diabetes influences skin innervation, and whether these changes are correlated with clinical signs and ...laboratory findings. To investigate these issues, we performed skin biopsies on the distal leg of 38 consecutive type 2 diabetic patients with sensory symptoms in lower limbs (25 males and 13 females, aged 56.2 ± 9.4 years) and analysed the correlations of intraepidermal nerve fibre (IENF) densities in skin with glycaemic status (duration of diabetes, HbA1C, and fasting and post‐prandial glucose levels), and functional parameters of small fibres (warm and cold thresholds) and large fibres (vibratory threshold and parameters of nerve conduction studies). Clinically, 23 patients (60.5%) had signs of small‐fibre impairment, and 19 patients (50.0%) had signs of large‐fibre impairment. IENF densities were much lower in diabetic patients than in age‐ and gender‐matched controls (1.794 ± 2.120 versus 9.359 ± 3.466 fibres/mm, P < 0.0001), and 81.6% (31/38) of diabetic patients had reduced IENF densities. IENF densities were negatively associated with the duration of diabetes (standardized coefficient: –0.422, P = 0.015) by analysis with a multivariate linear regression model. Abnormal results of functional examinations were present in 81.6% (warm threshold), 57.9% (cold threshold), 63.2% (vibratory threshold) and 49% (amplitude of sural sensory action potential) of diabetic patients. Among the three sensory thresholds, the warm threshold temperature had the highest correlation with IENF densities (standardized coefficient: –0.773, P < 0.0001). On nerve conduction studies in lower‐limb nerves, there were abnormal responses in 54.1% of sural nerves, and 50.0% of peroneal nerves. Of neurophysiological parameters, the amplitude of the sural sensory action potential had the highest correlation with IENF density (standardized coefficient: 0.739, P < 0.0001). On clinical examination, 15 patients showed no sign of small‐fibre impairment, but seven of these patients had reduced IENF densities. In conclusion, small‐fibre sensory neuropathy presenting with reduced IENF densities and correlated elevation of warm thresholds is a major manifestation of type 2 diabetes. In addition, the extent of skin denervation increases with diabetic duration.
Neutrophil extracellular traps (NETs) play a role in innate pathogen defense and also trigger B‐cell response by providing antigens. NETs have been linked to vaccine‐induced thrombotic ...thrombocytopenia. We postulated a potential link between NET biomarkers, NET‐promoting autoantibodies, and adverse events (AEs) after COVID‐19 vaccine boosters. Healthy donors (HDs) who received ChAdOx1‐S (A), mRNA‐1273 (M), or recombinant protein (MVC–COV1901) vaccines at the National Taiwan University Hospital between 2021 and 2022 were recruited. We measured serial NET‐associated biomarkers, citrullinated‐histone3 (citH3), and myeloperoxidase (MPO)‐DNA. Serum citH3 and MPO‐DNA were significantly or numerically higher in HDs who reported AEs (n = 100, booster Day 0/Day 30, p = 0.01/p = 0.03 and p = 0.30/p = 0.35, respectively). We also observed a positive correlation between rash occurrence in online diaries and elevated citH3. A linear mixed model also revealed significantly higher citH3 levels in mRNA‐1273/ChAdOx1‐S recipients than MVC‐COV1901 recipients. Significant positive correlations were observed between the ratios of anti‐heparin platelet factor 4 and citH3 levels on Booster Day 0 and naïve and between the ratios of anti‐NET IgM and citH3 on Booster Day 30/Day 0 in the AA‐M and MM‐M group, respectively. The increased levels of citH3/MPO‐DNA accompanied by NET‐promoting autoantibodies suggest a potential connection between mRNA‐1273/ChAdOx1‐S vaccines and cardiovascular complications. These findings provide insights for risk assessments of future vaccines.
Systemic lupus erythematosus (SLE) is an archetype of systemic autoimmune disease, characterized by the presence of diverse autoantibodies and chronic inflammation. There are multiple factors ...involved in lupus pathogenesis, including genetic/epigenetic predisposition, sexual hormone imbalance, environmental stimulants, mental/psychological stresses, and undefined events. Recently, many authors noted that "inflammaging", consisting of immunosenescence and inflammation, is a common feature in aging people and patients with SLE. It is conceivable that chronic oxidative stresses originating from mitochondrial dysfunction, defective bioenergetics, abnormal immunometabolism, and premature telomere erosion may accelerate immune cell senescence in patients with SLE. The mitochondrial dysfunctions in SLE have been extensively investigated in recent years. The molecular basis of normoglycemic metabolic syndrome has been found to be relevant to the production of advanced glycosylated and nitrosative end products. Besides, immunosenescence, autoimmunity, endothelial cell damage, and decreased tissue regeneration could be the results of premature telomere erosion in patients with SLE. Herein, the molecular and cellular bases of inflammaging and cardiovascular complications in SLE patients will be extensively reviewed from the aspects of mitochondrial dysfunctions, abnormal bioenergetics/immunometabolism, and telomere/telomerase disequilibrium.
Polymorphonuclear neutrophils (PMNs) are traditionally regarded as professional phagocytic and acute inflammatory cells that engulf the microbial pathogens. However, accumulating data have suggested ...that PMNs are multi-potential cells exhibiting many important biological functions in addition to phagocytosis. These newly found novel activities of PMN include production of different kinds of cytokines/chemokines/growth factors, release of neutrophil extracellular traps (NET)/ectosomes/exosomes and trogocytosis (membrane exchange) with neighboring cells for modulating innate, and adaptive immune responses. Besides, PMNs exhibit potential heterogeneity and plasticity in involving antibody-dependent cellular cytotoxicity (ADCC), cancer immunity, autoimmunity, inflammatory rheumatic diseases, and cardiovascular diseases. Interestingly, PMNs may also play a role in ameliorating inflammatory reaction and wound healing by a subset of PMN myeloid-derived suppressor cells (PMN-MDSC). Furthermore, PMNs can interact with other non-immune cells including platelets, epithelial and endothelial cells to link hemostasis, mucosal inflammation, and atherogenesis. The release of low-density granulocytes (LDG) from bone marrow initiates systemic autoimmune reaction in systemic lupus erythematosus (SLE). In clinical application, identification of certain PMN phenotypes may become prognostic factors for severe traumatic patients. In the present review, we will discuss these newly discovered biological and pathobiological functions of the PMNs.
Rituximab is known to be associated with high hepatitis B virus (HBV) reactivation rate in patients with resolved HBV infection and hematologic malignancy. However, data regarding HBV reactivation ...(HBVr) in rheumatic patients receiving rituximab is limited. To assess the HBVr rate in hepatitis B surface antigen (HBsAg)-negative patients receiving rituximab for autoimmune diseases in a large real-world cohort.
From March 2006 to December 2019, 900 patients with negative HBsAg receiving at least one cycle of rituximab for autoimmune diseases in a tertiary medical center in Taiwan were retrospectively reviewed. Clinical outcome and factors associated with HBVr were analyzed.
After a median follow-up period of 3.3 years, 21 patients developed HBVr, among whom 17 patients were positive for hepatitis B core antibody (anti-HBc) and four were negative. Thirteen patients had clinical hepatitis flare, while eight patients had HBsAg seroreversion without hepatitis. Old age, anti-HBc positivity, undetectable serum hepatitis B surface antibody level at rituximab initiation and a higher average rituximab dose were associated with a higher HBVr rate. There was no significant difference in the HBVr risk between rheumatoid arthritis and other autoimmune diseases. Among anti-HBc-negative patients, subjects without HBV vaccination at birth had an increased risk of HBVr (4/368, 1.1%) compared with those who received vaccination (0/126, 0%).
In HBV endemic areas where occult HBV is prevalent, anti-HBc-negative patients, may still be at risk for HBVr after rituximab exposure. HBVr may still be considered in HBsAg-negative patients developing abnormal liver function after rituximab exposure, even in patients with negative anti-HBc.