Effect of total flavonoids of Dracocephalum moldavica L. On neuroinflammation in Alzheimer's disease model amyloid-ß (Aß1-42)-peptide-induced astrocyte activation.

One of the main pathological features noted in Alzheimer's disease (AD) is the presence of plagues of aggregated ß-amyloid (Aß1-42)-peptides. Excess deposition of amyloid-ß oligomers (AßO) are known to promote neuroinflammation. Sequentially, following neuroinflammation astrocytes become activated with cellular characteristics to initiate activated astrocytes. The purpose of this study was to determine whether total flavonoids derived from Dracocephalum moldavica L. (TFDM) inhibited Aß1-42-induced damage attributed to activated C8-D1A astrocytes. Western blotting and ELISA were used to determine the expression of glial fibrillary acidic protein (GFAP), and complement C3 to establish the activation status of astrocytes following induction from exposure to Aß1-42. Data demonstrated that stimulation of C8-D1A astrocytes by treatment with 40 µM Aß1-42 for 24 hr produced significant elevation in protein expression and protein levels of acidic protein (GFAP) and complement C3 accompanied by increased expression and levels of inflammatory cytokines. Treatment with TFDM or the clinically employed drug donepezil in AD therapy reduced production of inflammatory cytokines, and toxicity initiated following activation of C8-D1A astrocytes following exposure to Aß1-42. Therefore, TFDM similar to donepezil inhibited inflammatory secretion in reactive astrocytes, suggesting that TFDM may be considered as a potential compound to be utilized in AD therapy.

Normobaric hyperoxia alleviates complement C3-mediated synaptic pruning and brain injury after intracerebral hemorrhage.

BACKGROUND: Intracerebral hemorrhage (ICH) is a common cerebrovascular disease, and the complement cascade exacerbates brain injury after ICH. As the most abundant component of the complement system, complement component 3 (C3) plays essential roles in all three complement pathways. However, the effects of C3 on neurological impairment and brain injury in ICH patients and the related mechanism have not been fully elucidated. Normobaric hyperoxia (NBO) is regarded as a treatment for ICH patients, and recent clinical studies also have confirmed the neuroprotective role of NBO against acute ICH-mediated brain damage, but the underlying mechanism still remains elusive. AIMS: In the present study, we investigated the effects of complement C3 on NBO-treated ICH patients and model mice, and the underlying mechanism of NBO therapy in ICH-mediated brain injury. RESULTS: Hemorrhagic injury resulted in the high plasma C3 levels in ICH patients, and the plasma C3 levels were closely related to hemorrhagic severity and clinical outcomes after ICH. BO treatment alleviated neurologic impairments and rescued the hemorrhagic-induced increase in plasma C3 levels in ICH patients and model mice. Moreover, the results indicated that NBO exerted its protective effects of on brain injury after ICH by downregulating the expression of C3 in microglia and alleviating microglia-mediated synaptic pruning. CONCLUSIONS: Our results revealed that NBO exerts its neuroprotective effects by reducing C3-mediated synaptic pruning, which suggested that NBO therapy could be used for the clinical treatment of ICH.

Inhibition of complement C3 prevents osteoarthritis progression in guinea pigs by blocking STAT1 activation.

Osteoarthritis (OA) is one of the leading causes of disability, affecting over 500 million adults worldwide. Previous studies have found that various inflammatory factors can contribute to the pathogenesis of OA, including complement factors in the synovial fluid of OA patients. However, the pathogenesis of this disease is still not known, and the only therapy of severe OA is total joint replacements. Total joint replacements are invasive, expensive, and affect quality of life. Here we show that when human articular chondrocytes are stimulated with pro-inflammatory mediator interleukin-1ß (IL-1ß) there is an increase in inflammatory factors including complement component 3 (C3). We also found the transcription factor, signal transducer and activator of transcription 1 (STAT1), is responsible for increased C3 expression after IL-1ß stimulation in human articular chondrocytes. A specific STAT1 inhibitor, fludarabine, attenuates the hyper-expression of C3 and delays/prevents spontaneous OA in Dunkin-Hartley guinea pigs. Since fludarabine is already clinically used for chemotherapy, this study has great translational potential as a unique disease-modifying osteoarthritis drug (DMOAD) in treating primary OA.

Effects of empagliflozin on collagen biomarkers in patients with heart failure: Findings from the EMPEROR trials.

AIMS: Extracellular matrix remodelling is one of the key pathways involved in heart failure (HF) progression. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) may have a role in attenuating myocardial fibrosis. The impact of SGLT2i on blood markers of collagen turnover in humans is not fully elucidated. This study aimed to investigate the effect of empagliflozin on serum markers of collagen turnover in patients enrolled in the EMPEROR-Preserved and EMPEROR-Reduced trials. METHODS AND RESULTS: Overall, 1084 patients (545 in empagliflozin and 539 in placebo) were included in the analysis. Procollagen type I carboxy-terminal propeptide (PICP), a fragment of N-terminal type III collagen (PRO-C3), procollagen type I amino-terminal peptide (PINP), a fragment of C-terminal type VIa3 collagen (PRO-C6), a fragment of type I collagen (C1M), and a fragment of type III collagen (C3M) were measured in serum at baseline, 12 and 52 weeks. A mixed model repeated measurements model was used to evaluate the effect of empagliflozin versus placebo on the analysed biomarkers. Higher baseline PICP, PRO-C6 and PINP levels were associated with older age, a more severe HF presentation, higher levels of natriuretic peptides and high-sensitivity troponin T, and the presence of comorbid conditions such as chronic kidney disease and atrial fibrillation. Higher PICP levels were associated with the occurrence of the study primary endpoint (a composite of HF hospitalization or cardiovascular death), and PRO-C6 and PINP were associated with the occurrence of sustained worsening of kidney function. On the other hand, PRO-C3, C1M, and C3M were not associated with worse HF severity or study outcomes. Compared to placebo, empagliflozin reduced PICP at week 12 by 5% and at week 52 by 8% (week 12: geometric mean ratio = 0.95, 95% confidence interval [CI] 0.91-0.99, p = 0.012; week 52: geometric mean ratio = 0.92, 95% CI 0.88-0.97, p = 0.003). Additionally, empagliflozin reduced PRO-C3 at week 52 by 7% (week 12: geometric mean ratio = 0.98, 95% CI 0.95-1.02, p = 0.42; week 52: geometric mean ratio = 0.93, 95% CI 0.89-0.98, p = 0.003), without impact on other collagen markers. CONCLUSION: Our observations are consistent with experimental observations that empagliflozin down-regulates profibrotic signalling. The importance of such an effect for the clinical benefits of SGLT2i in HF remains to be elucidated.

Metabolic syndrome in systemic lupus erythematosus patients under Mediterranean diet.

BACKGROUND AND AIMS: Metabolic syndrome (MetS) is a chronic proinflammatory and prothrombotic condition that exacerbates insulin resistance, oxidative damage, and cardiovascular risk, being more prevalent in patients with systemic lupus erythematosus (SLE), a chronic multisystemic autoimmune disorder. This study aim was to determine the prevalence of MetS and associations with SLE clinical characteristics, cardiovascular risk and dietary pattern in a population of Spanish SLE patients. DESIGN AND METHODS: Cross-sectional study of 293 patients was conducted (90.4% females; mean age 46.8 (12.94)). The diagnosis of MetS was established based on the criteria of the National Cholesterol Education Program Adult Treatment Panel III. SLE Disease Activity Index (SLEDAI-2K) and SDI Damage Index were used to assess disease activity and disease-related damage, respectively. Med Diet adherence was assessed through a 14 items questionnaire on food consumption frequency and habits. RESULTS: MetS was present in 15% SLE patients. Triglycerides, high-density lipoprotein cholesterol, systolic blood pressure and waist circumference were significantly increased (p<0.001) in the group of MetS patients. Patients with MetS showed significantly increased SDI damage index (1.70 (1.69) vs 0.88 (1.12), p<0.001) and complement C3 level (118.70 (32.67) vs 107.55 (26.82), p=0.011). No significant differences were observed according to Med Diet adherence level. CONCLUSION: We observed a lower prevalence of MetS in SLE than that reported in previous studies, which may be a result of the good level of adherence to the MedDiet in our study sample. Additionally, MetS was associated with higher SDI and complement C3 levels but no with medication use.

Complement Inhibition in Paroxysmal Nocturnal Hemoglobinuria (PNH): A Systematic Review and Expert Opinion from Central Europe on Special Patient Populations.

INTRODUCTION: Hemolysis in paroxysmal nocturnal hemoglobinuria (PNH) is complement-mediated due to the lack of complement inhibitors in the hemopoietic cell membranes, making complement inhibition the best approach to manage PNH. Three complement inhibitors are approved by the European Medicines Agency as targeted therapy for PNH: eculizumab and ravulizumab, two humanized monoclonal antibodies targeting the same complement 5 (C5) epitope, approved in 2007 and 2019, respectively, and the more recently approved cyclic peptide, the complement 3 (C3) inhibitor pegcetacoplan. Although national and international PNH treatment guidelines exist, they do not take into consideration the latest clinical trial evidence. Given the lack of evidence-based data for some clinical situations encountered in real life, we identified specific populations of patients who may benefit from switching to proximal C3 from terminal C5 inhibition. METHODS: The expert recommendations presented here were created using a Delphi-like process by a group of expert PNH specialists across Central Europe. Based on an initial advisory board meeting discussion, recommendations were prepared and reviewed as part of a Delphi survey to test agreement. RESULTS: Using a systematic approach, literature databases were searched for relevant studies, and 50 articles were reviewed by the experts and included as supporting evidence. CONCLUSION: Implementation of these recommendations uniformly across healthcare institutions will promote the best use of complement inhibition in managing PNH, and has the potential to positively impact patient outcomes in Central Europe and worldwide.

Levels of extracellular matrix metabolites are associated with changes in Ankylosing Spondylitis Disease Activity Score and MRI inflammation scores in patients with axial spondyloarthritis during TNF inhibitor therapy.

BACKGROUND/PURPOSE: In axial spondyloarthritis (axSpA) inflammation of the sacroiliac joints and spine is associated with local extracellular matrix (ECM) remodeling of affected tissues. We aimed to investigate the association of ECM metabolites with treatment response in axSpA patients treated with TNF-α inhibitory therapy for 46 weeks. METHODS: In a prospective clinical study of axSpA patients (n=55) initiating a TNF inhibitor (infliximab, etanercept, or adalimumab), serum concentrations of formation of type I (PRO-C1), type III (PRO-C3), and type VI (PRO-C6) collagen; turnover of type IV collagen (PRO-C4), and matrix-metalloproteinase (MMP)-degraded type III (C3M) collagen, MMP-degraded type IV (C4M), type VI (C6M), and type VII (C7M) collagen, and cathepsin-degraded type X collagen (C10C), MMP-mediated metabolite of C-reactive protein (CRPM), citrullinated vimentin (VICM), and neutrophil elastase-degraded elastin (EL-NE) were measured at baseline, week 2, week 22, and week 46. RESULTS: Patients were mostly males (82%), HLA-B27 positive (84%), with a median age of 40 years (IQR: 32-48), disease duration of 5.5 years (IQR: 2-10), and a baseline Ankylosing Spondylitis Disease Activity Score (ASDAS) of 3.9 (IQR: 3.0-4.5). Compared to baseline, PRO-C1 levels were significantly increased after two weeks of treatment, C6M levels were significantly decreased after two and 22 weeks (repeated measures ANOVA, p=0.0014 and p=0.0015, respectively), EL-NE levels were significantly decreased after 2 weeks (p=0.0008), VICM levels were significantly decreased after two and 22 weeks (p=0.0163 and p=0.0374, respectively), and CRP were significantly decreased after two and 22 weeks (both p=0.0001). Baseline levels of PRO-C1, PRO-C3, C6M, VICM, and CRP were all associated with ASDAS clinically important and major improvement after 22 weeks (ΔASDAS ≥1.1) (Mann-Whitney test, p=0.006, p=0.008, p<0.001, <0.001, <0.001, respectively), while C6M, VICM and CRP levels were associated with ASDAS clinically important and major improvement after 46 weeks (ΔASDAS ≥2.0) (p=0.002, p=0.044, and p<0.001, respectively). PRO-C1 and C6M levels were associated with a Bath AS Disease Activity Score (BASDAI) response to TNF-inhibitory therapy after 22 weeks (Mann-Whitney test, p=0.020 and p=0.049, respectively). Baseline levels of PRO-C4 and C6M were correlated with the total SPARCC MRI Spine and Sacroiliac Joint Inflammation score (Spearman's Rho ρ=0.279, p=0.043 and ρ=0.496, p=0.0002, respectively). CONCLUSIONS: Extracellular matrix metabolites were associated with ASDAS response, MRI inflammation, and clinical treatment response during TNF-inhibitory treatment in patients with axSpA.

Pegcetacoplan treatment for geographic atrophy due to age-related macular degeneration: a plain language summary of the FILLY study.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of a publication about the FILLY study, which was published in Ophthalmology in 2020. The FILLY study looked at an investigational medicine called pegcetacoplan as a possible treatment for geographic atrophy. Geographic atrophy, also known as GA, is the late stage of an eye disease called dry age-related macular degeneration, also known as dry AMD. In people with GA, lesions form on a part of the back of the eye called the retina. GA lesions are patches of thin retina. Growth of GA lesions ultimately causes blindness, which cannot be reversed. There is currently no approved treatment for GA. Pegcetacoplan, also called APL-2, could be a possible treatment for GA. Pegcetacoplan is an investigational medicine, which means it has not yet been approved. It is currently being studied in clinical studies to see how well it works. WHAT HAPPENED IN THE FILLY STUDY?: The FILLY study included participants with GA and tested how well pegcetacoplan worked compared to a sham injection (an injection that looks like the study treatment but does not have any medicine in it). The study also looked at how safe it was in adults with GA. WHAT WERE THE RESULTS?: The main questions the researchers wanted to answer were: Did pegcetacoplan slow the growth of the study participants' GA lesions? ○Yes. Overall, the researchers found that pegcetacoplan did slow the growth of the study participants' GA lesions. Did pegcetacoplan change the participants' vision? ○No. Overall, the researchers found that pegcetacoplan did not change the participants' vision. What medical problems happened after the participants received pegcetacoplan? ○The researchers kept track of any serious medical problems that happened during the study, also called serious adverse events. They also kept track of other medical problems that happened, or got worse, only at some point after the participants received the study treatment. These are called treatment emergent adverse events, also known as TEAEs. The serious adverse events and TEAEs that the participants had are described later in this summary. WHAT DO THE RESULTS OF THE STUDY MEAN?: Overall, results from this study showed that participants who received pegcetacoplan had slower growth of GA lesions than participants who received the sham injection. After the participants had stopped receiving pegcetacaoplan, the effect of the treatment seemed to be reduced. Pegcetacoplan did not change how well the participants could see during their vision tests in this trial. ClinicalTrials.gov NCT number: NCT02503332.

Compstatins: the dawn of clinical C3-targeted complement inhibition.

Despite the growing recognition of the complement system as a major contributor to a variety of clinical conditions, the therapeutic arsenal has remained scarce. The introduction of an anti-C5 antibody in 2007 raised confidence in complement-targeted therapy. However, it became apparent that inhibition of late-stage effector generation might not be sufficient in multifactorial complement disorders. Upstream intervention at the level of C3 activation has therefore been considered promising. The approval of pegcetacoplan, a C3 inhibitor of the compstatin family, in 2021 served as critical validation of C3-targeted treatment. This review delineates the evolution of the compstatin family from its academic origins to the clinic and highlights current and potential future applications of this promising drug class in complement diseases.

Absence of complement component 3 does not prevent classical pathway-mediated hemolysis.

Complement component 3 (C3) is emerging as a potential therapeutic target. We studied complement-mediated hemolysis using normal and C3-depleted human sera, wild-type (WT) and C3-deficient rat sera, and WT and C3 knockout rat models. In all of the in vitro and in vivo experiments, we found that the loss of C3 did not prevent classical pathway-mediated hemolysis, but it did almost abolish alternative pathway-mediated hemolysis. Experiments using preassembled classical pathway C3 convertases confirmed that C4b2a directly activated complement component 5 (C5), leading to membrane attack complex formation and hemolysis. Our results suggest that targeting C3 should effectively inhibit hemolysis and tissue damage mediated by the alternative pathway of complement activation, but this approach might have limited efficacy in treating classical pathway-mediated pathological conditions.