Reactive oxygen species: The Yin and Yang in (auto-)immunity

USP18 induction regulates immunometabolism to attenuate M1 signal-polarized macrophages and enhance IL-4-polarized macrophages in systemic lupus erythematosus

Effective treatment of systemic lupus erythematosus (SLE) remains an unmet need. Different subsets of macrophages play differential roles in SLE and the modulation of macrophage polarization away from M1 status is beneficial for SLE therapeutics. Given the pathogenic roles of type I interferons (IFN-I) in SLE, this study investigated the effects and mechanisms of a mitochondria localization molecule ubiquitin specific peptidase 18 (USP18) preserving anti-IFN effects and isopeptidase activity on macrophage polarization. After observing USP18 induction in monocytes from SLE patients, we studied mouse bone marrow-derived macrophages and showed that USP18 deficiency increased M1signal (LPS + IFN-γ treatment)-induced macrophage polarization, and the effects involved the induction of glycolysis and mitochondrial respiration and the expression of several glycolysis-associated enzymes and molecules, such as hypoxia-inducible factor-1α. Moreover, the effects on mitochondrial activities, such as mitochondrial DNA release and mitochondrial reactive oxygen species production were observed. In contrast, the overexpression of USP18 inhibited M1signal-mediated and enhanced interleukin-4 (IL-4)-mediated polarization of macrophages and the related cellular events. Moreover, the levels of USP18 mRNA expression showed tendency of correlation with the expression of metabolic enzymes in monocytes from patients with SLE. We thus concluded that by preserving anti-IFN effect and downregulating M1 signaling, promoting USP18 activity may serve as a useful approach for SLE therapeutics.

The 330 risk loci known for systemic lupus erythematosus (SLE): a review

An in-depth literature review of up to 2023 reveals 330 risk loci found by genetic association at p ≤ 5 × 10-8, with systemic lupus erythematosus (SLE) in at least one study of 160 pertinent publications. There are 225 loci found in East Asian (EAS), 106 in European (EU), 11 in African-American (AA), 18 Mixed American (MA), and 1 in Egyptian ancestries. Unexpectedly, most of these associations are found to date at p ≤ 5 × 10-8 in a single ancestry. However, the EAS and EU share 40 risk loci that are independently established. The great majority of the identified loci [250 (75.8%) of 330] do not contain a variant that changes an amino acid sequence. Meanwhile, most overlap with known regulatory elements in the genome [266 (80.6%) of 330], suggesting a major role for gene regulation in the genetic mechanisms of SLE. To evaluate the pathways altered by SLE-associated variants, we generated gene sets potentially regulated by SLE loci that consist of the nearest genes, published attributions, and genes predicted by computational tools. The most useful insights, at present, suggest that SLE genetic mechanisms involve (1) the regulation of both adaptive and innate immune responses including immune cell activation and differentiation; (2) the regulation of production and response to cytokines, including type I interferon; (3) apoptosis; (4) the sensing and removal of immune complexes and apoptotic particles; and (5) immune response to infections, including Epstein-Barr Virus, and symbiont microorganisms. These mechanisms affected by SLE genes involve multiple cell types, including B cells/plasma cells, T cells, dendritic cells, monocytes/macrophages, natural killer cells, neutrophils, and endothelial cells. The genetics of SLE from GWAS data reveal an incredibly complex profusion of interrelated molecular processes and interacting cells participating in SLE pathogenesis, mostly unified in the molecular regulation of inflammatory responses. These genetic associations in lupus and affected molecular pathways not only give us an understanding of the disease pathogenesis but may also help in drug discoveries for SLE treatment.

Selective Organ-Targeting Hafnium Oxide Nanoparticles with Multienzyme-Mimetic Activities Attenuate Radiation-Induced Tissue Damage

Radioprotective agents hold clinical promises to counteract off-target adverse effects of radiation and benefit radiotherapeutic outcomes, yet the inability to control drug transport in human organs poses a leading limitation. Based upon a validated rank-based multigene signature model, radiosensitivity indices are evaluated of diverse normal organs as a genomic predictor of radiation susceptibility. Selective ORgan-Targeting (SORT) hafnium oxide nanoparticles (HfO2 NPs) are rationally designed via modulated synthesis by α-lactalbumin, homing to top vulnerable organs. HfO2 NPs like Hensify are commonly radioenhancers, but SORT HfO2 NPs exhibit surprising radioprotective effects dictated by unfolded ligands and Hf(0)/Hf(IV) redox couples. Still, the X-ray attenuation patterns allow radiological confirmation in target organs by dual-beam spectral computed tomography. SORT HfO2 NPs present potent antioxidant activities, catalytically scavenge reactive oxygen species, and mimic multienzyme catalytic activities. Consequently, SORT NPs rescue radiation-induced DNA damage in mouse and rabbit models and provide survival benefits upon lethal exposures. In addition to inhibiting radiation-induced mitochondrial apoptosis, SORT NPs impede DNA damage and inflammation by attenuating activated FoxO, Hippo, TNF, and MAPK interactive cascades. A universal methodology is proposed to reverse radioenhancers into radioprotectors. SORT radioprotective agents with image guidance are envisioned as compelling in personalized shielding from radiation deposition.

Ferroptosis: a new target for hepatic ischemia-reperfusion injury?

Ischemia-reperfusion injury (IRI) can seriously affect graft survival and prognosis and is an unavoidable event during liver transplantation. Ferroptosis is a novel iron-dependent form of cell death characterized by iron accumulation and overwhelming lipid peroxidation; it differs morphologically, genetically, and biochemically from other well-known cell death types (autophagy, necrosis, and apoptosis). Accumulating evidence has shown that ferroptosis is involved in the pathogenesis of hepatic IRI, and targeting ferroptosis may be a promising therapeutic approach. Here, we review the pathways and phenomena involved in ferroptosis, explore the associations and implications of ferroptosis and hepatic IRI, and discuss possible strategies for modulating ferroptosis to alleviate the hepatic IRI.

Benign prostatic hyperplasia - A novel autoimmune disease with a potential therapy consequence?

Benign prostatic hyperplasia (BPH) is considered as an age-related disease of men with an unknown etiopathophysiology. Chronic inflammation has been proposed as one of the major pathophysiological mechanisms. There is growing evidence for the involvement of autoimmune responses in an inflammatory setting in the prostate. Patients with autoimmune diseases show a significantly elevated prevalence of BPH. Conventional therapy options for BPH are limited, rendering surgery the ultimate alternative. However, immunosuppression via tumor necrosis factor alpha blocker appears to reduce symptoms in patients with BPH and concurrent autoimmune disease due to the reduction of epithelial hyperplasia and macrophage-induced inflammation. New diagnostic options using HEp-2 cells with overexpression of LEDGF/p75 or mitochondrial DNA as autoimmune targets could be used to identify BPH patients with autoimmune responses. Given the presumed involvement of autoimmune responses in BPH and the efficacy of immunosuppression in reducing BPH symptoms, BPH or subvariants of BPH may be candidates for a new autoimmune disease in males.

Cardiovascular Risk in Patients With Glomerular Disease: A Narrative Review of the Epidemiology, Mechanisms, Management, and Patient Priorities

Purpose of review

Cardiovascular (CV) disease is a major cause of morbidity and mortality for patients with glomerular disease. Despite the fact that mechanisms underpinning CV disease risk in this population are likely distinct from other forms of kidney disease, treatment and preventive strategies tend to be extrapolated from studies of patients with undifferentiated chronic kidney disease (CKD). There is an unmet need to delineate the pathophysiology of CV disease in patients with glomerular disease, establish unique risk factors, and identify novel therapeutic targets for disease prevention. The aims of this narrative review are to summarize the existing knowledge regarding the epidemiology, molecular mechanisms, and management of CV disease in patients with common glomerular disease, highlight the patient perspective, and propose specific areas for future study.

Sources of information

The literature for this narrative review was accessed using common research search engines, including PubMed, PubMed Central, Medline, and Google Scholar. Information for the patient perspective section was collected through iterative discussions with a patient partner.

Methods

We reviewed the epidemiology, molecular mechanisms of disease, management approaches, and the patient perspective in relation to CV disease in patients with glomerulopathies. Throughout, we have highlighted the current knowledge and have discussed future research approaches, both clinical and translational, while integrating the patient perspective.

Key findings

Patients with glomerular disease have significant CV disease risk driven by multifactorial, molecular mechanisms originating from their glomerular disease but complicated by existing comorbidities, kidney disease, and medication side effects. The current approach to risk stratification and treatment relies heavily on existing data from CKD patients, but this may not always be appropriate given the unique pathophysiology and mechanisms associated with CV disease risk in patients with glomerular disease. We highlight the need for ongoing glomerular disease-focused studies aimed to better delineate CV disease risk, while integrating the patient perspective.

Limitations

This is a narrative review and does not represent a comprehensive and systematic review of the literature.

Biomarkers of Oxidative Stress in Systemic Lupus Erythematosus Patients with Active Nephritis

Oxidative stress plays an important role in systemic lupus erythematosus (SLE) and especially in lupus nephritis (LN). The aim of this study was to compare redox-related biomarkers between patients with active LN, quiescent SLE (Q-SLE) and healthy controls (HC) and to explore their association with clinical characteristics such as disease activity in patients. We investigated levels of plasma free thiols (R-SH, sulfhydryl groups), levels of soluble receptor for advanced glycation end products (sRAGE) and levels of malondialdehyde (MDA) in SLE patients with active LN (n = 23), patients with quiescent SLE (n = 47) and HC (n = 23). Data of LN patients who previously participated in Dutch lupus nephritis studies and longitudinal samples up to 36 months were analyzed. Thiol levels were lower in active LN at baseline and Q-SLE patients compared to HC. In generalized estimating equation (GEE) modelling, free thiol levels were negatively correlated with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) over time (p < 0.001). sRAGE and MDA were positively correlated with the SLEDAI over time (p = 0.035 and p = 0.016, respectively). These results indicate that oxidative stress levels in LN patients are increased compared to HC and associated with SLE disease activity. Therefore, interventional therapy to restore redox homeostasis may be useful as an adjunctive therapy in the treatment of oxidative damage in SLE.

Measurement of superoxide dismutase: clinical usefulness for patients with anti-neutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

To investigate the clinical usefulness of serum superoxide dismutase (SOD) measurement in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

In this single-center retrospective study, demographic data, serum SOD levels, erythrocyte sedimentation rate (ESR), C reactive protein (CRP), the Birmingham Vasculitis Activity Score (BVAS), ANCA, organ involvement, and outcomes were analyzed for 152 AAV patients hospitalized in the Second Affiliated Hospital of Chongqing Medical University. Meanwhile, the serum SOD levels of 150 healthy people were collected as the control group.

RESULTS

Compared to the healthy control group, serum SOD levels of the AAV group were significantly lower (P < 0.001). SOD levels of AAV patients were negatively correlated to ESR, CRP, and BVAS (ESR rho = - 0.367, P < 0.001; CRP rho = - 0.590, P < 0.001; BVAS rho = - 0.488, P < 0.001). SOD levels for the MPO-ANCA group were significantly lower than the PR3-ANCA group (P = 0.045). SOD levels for the pulmonary involvement group and the renal involvement group were significantly lower than those for the non-pulmonary involvement group and the non-renal involvement group (P = 0.006; P < 0.001, respectively). SOD levels in the death group were significantly lower than the survival group (P = 0.001).

CONCLUSIONS

In AAV patients, low SOD levels might indicate disease associated oxidative stress. SOD levels in AAV patients were decreased with inflammation, suggesting that SOD levels could potentially be a surrogate marker for disease activity. SOD levels in AAV patients were closely related to ANCA serology, pulmonary involvement, and renal involvement, with low SOD levels an important indicator of a poor prognosis for AAV patients.

Converting commonly-used paper into nano-engineered fluorescent biomass-based platform for rapid ClO- quantitative detection in living cells and water sources

Hypochlorous acid (HClO) and derivative ionic form (ClO^-) are significant components of reactive oxygen species, and thus various diseases are correlatively related to the concentration of ClO^-. Recently, paper-based indicators have been confirmed to be efficient strategy for sensing hazardous and noxious substances. However, most of these materials can only achieve qualitative detection of the substrates. Herein, an extremely simple manufacturing strategy was proposed to convert commonly-used paper into nano-engineered fluorescent biomass-based platform (CMJL-FP) integrated with on-demand self-assembled colorimetric and ratiometric fluorescence sensor (CMJL) for rapid ClO^- quantitative detection in organisms or water sources using smartphones. The CMJL exhibited a highly selective and sensitive ratiometric response to ClO^- at a low detection limit (LOD = 92.6 nM). The associating interactions between the fluorescence nano-particles and micro-nano fibers of CMJL-FP ensure good-stability during ClO^- detection. It has been experimentally demonstrated that CMJL-FP allows one to realize the rapid quantitative detection of ClO^- ions in living cells and large-scale water sources by using color recognition software as part of a simple smartphone. Therefore, integrating the proposed fluorescent paper with smartphones provides an effective, sustainable, cheap and conceptual strategy for quantitative detection of hazardous and noxious substances in organisms and environments.

Functional Genome Analysis for Immune Cells Provides Clues for Stratification of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is caused by a combination of genetic and environmental factors. Recently, analysis of a functional genome database of genetic polymorphisms and transcriptomic data from various immune cell subsets revealed the importance of the oxidative phosphorylation (OXPHOS) pathway in the pathogenesis of SLE. In particular, activation of the OXPHOS pathway is persistent in inactive SLE, and this activation is associated with organ damage. The finding that hydroxychloroquine (HCQ), which improves the prognosis of SLE, targets toll-like receptor (TLR) signaling upstream of OXPHOS suggests the clinical importance of this pathway. IRF5 and SLC15A4, which are regulated by polymorphisms associated with SLE susceptibility, are functionally associated with OXPHOS as well as blood interferon activity and metabolome. Future analyses of OXPHOS-associated disease-susceptibility polymorphisms, gene expression, and protein function may be useful for risk stratification of SLE.

Polysaccharides as antioxidants and prooxidants in managing the double-edged sword of reactive oxygen species

Polysaccharides, a class of naturally occurring carbohydrates, were widely presented in animals, plants, and microorganisms. Recently, health benefits of polysaccharides have attracted much attention due to their unique characteristics in reactive oxygen species (ROS) management. ROS, by-products of aerobic metabolism linked to food consumption, exhibited a dual role in protecting cells and fostering pathogenesis collectively termed double-edged sword. Some interesting studies reported that polysaccharides could behave as prooxidants under certain conditions, besides antioxidant capacities. Potentiation of the bright side of ROS could contribute to the host defense that was vitally important for the polysaccharides acting as biological response modifiers. Correspondingly, disease prevention of polysaccharides linked to the management of ROS production was systematically described and discussed in this review. Furthermore, major challenges and future prospects were presented, aiming to provide new insight into applying polysaccharides as functional food ingredients and medicine.

BDE-47 Induces Immunotoxicity in RAW264.7 Macrophages through the Reactive Oxygen Species-Mediated Mitochondrial Apoptotic Pathway

Polybrominated diphenyl ethers (PBDEs) are classic and emerging pollutants that are potentially harmful to the human immune system. Research on their immunotoxicity and mechanisms suggests that they play an important role in the resulting pernicious effects of PBDEs. 2,2',4,4'-Tetrabrominated biphenyl ether (BDE-47) is the most biotoxic PBDE congener, and, in this study, we evaluated its toxicity toward RAW264.7 cells of mouse macrophages. The results show that exposure to BDE-47 led to a significant decrease in cell viability and a prominent increase in apoptosis. A decrease in mitochondrial membrane potential (MMP) and an increase in cytochrome C release and caspase cascade activation thus demonstrate that cell apoptosis induced by BDE-47 occurs via the mitochondrial pathway. In addition, BDE-47 inhibits phagocytosis in RAW264.7 cells, changes the related immune factor index, and causes immune function damage. Furthermore, we discovered a significant increase in the level of cellular reactive oxygen species (ROS), and the regulation of genes linked to oxidative stress was also demonstrated using transcriptome sequencing. The degree of apoptosis and immune function impairment caused by BDE-47 could be reversed after treatment with the antioxidant NAC and, conversely, exacerbated by treatment with the ROS-inducer BSO. These findings indicate that oxidative damage caused by BDE-47 is a critical event that leads to mitochondrial apoptosis in RAW264.7 macrophages, ultimately resulting in the suppression of immune function.

Deregulated DNA damage response network in Behcet's disease

Behcet's disease (BD) is a chronic, relapsing systemic vasculitis of unknown etiology. Since the DNA repair enzyme NEIL1 has been identified as one of the two genetic risk factors for BD by whole exome study, we examined the potential involvement of the DNA damage response (DDR) network in BD. Peripheral blood mononuclear cells from 26 patients and 26 age-/sex-matched healthy controls were studied. Endogenous DNA damage levels were increased in active BD patients compared to controls or patients in remission. In parallel, BD patients had defective nucleotide excision repair capacity. RNA-sequencing revealed reduced expression of NEIL1 that negatively correlated with DNA damage accumulation. On the other hand, expression of genes involved in senescence and senescence-associated secretory phenotype positively correlated with individual endogenous DNA damage levels. We conclude that deregulated DDR contributes to the proinflammatory environment in BD.

Phosphofructokinase P fine-tunes T regulatory cell metabolism, function, and stability in systemic autoimmunity

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by defective regulatory T (Treg) cells. Here, we demonstrate that a T cell-specific deletion of calcium/calmodulin-dependent protein kinase 4 (CaMK4) improves disease in B6.lpr lupus-prone mice and expands Treg cells. Mechanistically, CaMK4 phosphorylates the glycolysis rate-limiting enzyme 6-phosphofructokinase, platelet type (PFKP) and promotes aerobic glycolysis, while its end product fructose-1,6-biphosphate suppresses oxidative metabolism. In Treg cells, a CRISPR-Cas9-enabled Pfkp deletion recapitulated the metabolism of Camk4-/- Treg cells and improved their function and stability in vitro and in vivo. In SLE CD4+ T cells, PFKP enzymatic activity correlated with SLE disease activity and pharmacologic inhibition of CaMK4-normalized PFKP activity, leading to enhanced Treg cell function. In conclusion, we provide molecular insights in the defective metabolism and function of Treg cells in SLE and identify PFKP as a target to fine-tune Treg cell metabolism and thereby restore their function.

Colorimetric/SERS dual-channel nanoprobe for reactive oxygen species monitoring in elucidating the mechanism of chemotherapeutic drugs action on cancer cells

Reactive oxygen species (ROS) are involved in drug-induced cytotoxicity by regulating cell signaling, inducing oxidative stress, and damaging the DNA and proteins. Examining ROS production in cells under the stimulation of chemotherapeutic drugs is of great importance for understanding the ROS roles and identifying the mechanism of drug-induced cytotoxicity. Here, a silver/gold (Ag/Au) nanoshell-based colorimetric and surface-enhanced Raman spectroscopy (SERS) dual-response nanoprobe was proposed for ROS sensing on the basis of Ag etching. In this study, as a kind of ROS, hydrogen peroxide (H₂O₂) was detected by the prepared nanoprobe. The linear ranges of 0.5-100 μM with a limit of detection (LOD) of 0.343 μM for the colorimetric determination and 1-50 μM with LOD of 0.294 μM for SERS determination were achieved. The detection of cellular ROS concentration after stimulation by cisplatin, paclitaxel, doxorubicin, and 5-fluorouracil was validated by the nanoprobe. The nanoprobe could also be used to detect the signal pathway of ROS production by cisplatin stimulation. This study provided a simple and novel dual-response nanoplatform for detecting and monitoring ROS in cells, which holds great potential for elucidating the mechanism of occurrence and treatment of ROS-involved diseases.

Meta-Analysis and Systematic Review of the Association between a Hypoactive NCF1 Variant and Various Autoimmune Diseases

Genetic association studies have discovered the GTF2I-NCF1 intergenic region as a strong susceptibility locus for multiple autoimmune disorders, with the missense mutation NCF1 rs201802880 as the causal polymorphism. In this work, we aimed to perform a comprehensive meta-analysis of the association of the GTF2I-NCF1 locus with various autoimmune diseases and to provide a systemic review on potential mechanisms underlying the effect of the causal NCF1 risk variants. The frequencies of the two most extensively investigated polymorphisms within the locus, GTF2I rs117026326 and NCF1 rs201802880, vary remarkably across the world, with the highest frequencies in East Asian populations. Meta-analysis showed that the GTF2I-NCF1 locus is significantly associated with primary Sjögren's syndrome, systemic lupus erythematosus, systemic sclerosis, and neuromyelitis optica spectrum disorder. The causal NCF1 rs201802880 polymorphism leads to an amino acid substitution of p.Arg90His in the p47phox subunit of the phagocyte NADPH oxidase. The autoimmune disease risk His90 variant results in a reduced ROS production in phagocytes. Clinical and experimental evidence shows that the hypoactive His90 variant might contribute to the development of autoimmune disorders via multiple mechanisms, including impairing the clearance of apoptotic cells, regulating the mitochondria ROS-associated formation of neutrophil extracellular traps, promoting the activation and differentiation of autoreactive T cells, and enhancing type I IFN responses. In conclusion, the identification of the association of NCF1 with autoimmune disorders demonstrates that ROS is an essential regulator of immune tolerance and autoimmunity mediated disease manifestations.

Conscription of Immune Cells by Light-Activatable Silencing NK-Derived Exosome (LASNEO) for Synergetic Tumor Eradication

Exosomes derived from natural killer (NK) cells (NEO) constitute promising antineoplastic nano-biologics because of their versatile functions in immune regulation. However, a significant augment of their immunomodulatory capability is an essential need to achieve clinically meaningful treatment outcomes. Light-activatable silencing NK-derived exosomes (LASNEO) are orchestrated by engineering the NEO with hydrophilic small interfering RNA (siRNA) and hydrophobic photosensitizer Ce6. Profiling of genes involved in apoptosis pathway with Western blot and RNA-seq in cells receiving NEO treatment reveals that NEO elicits effective NK cell-like cytotoxicity toward tumor cells. Meanwhile, reactive oxygen species (ROS) generation upon laser irradiation not only triggers substantial photodynamic therapy effect but also boosts M1 tumor-associated macrophages polarization and DC maturation in the tumor microenvironment (TME). In addition, ROS also accelerates the cellular entry and endosomal escape of siRNA in TME. Finally, siRNAs targeting PLK1 or PD-L1 induce robust gene silencing in cancer cells, and downregulation of PD-L1 restores the immunological surveillance of T cells in TME. Therefore, the proposed LASNEO exhibit excellent antitumor effects by conscripting multiple types of immune cells. Considering that its manufacture is quite simple and controllable, LASNEO show compelling potential for clinical translational application.

Registered human trials addressing environmental and occupational toxicant exposures: Scoping review of immunological markers and protective strategies

Exposure to pollution is a worldwide societal challenge participating in the etiology and progression of different diseases. However, the scarce information hinders our understanding of the actual level of human exposure and its specific effects. Inadequate and excessive immune responses underlie diverse chronic diseases. Yet, it is unclear which and how toxicant exposures affect the immune system functions. There is a multiplicity of immunological outcomes and biomarkers being studied in human trials related to exposure to different toxicants but still without clear evidence of their value as biomarkers of exposure or effect. The main aim of this study was to collect scientific evidence and identify relevant immunological biomarkers used at the clinical level for toxicant exposures. We used the platform clinical trials.gov as a database tool. First, we performed a search combining research items related to toxicants and immunological parameters. The resulting117 clinical trials were examined for immune-related outcomes and specific biomarkers evaluated in subjects exposed to occupational and environmental toxicants. After categorization, relevant immunological outcomes and biomarkers were identified related to systemic and airway inflammation, modulation of immune cells, allergy and autoimmunity. In general, the immune markers related to inflammation are more frequently investigated for exposure to pollutants, namely IL-6, C-reactive protein (CRP) and nitric oxide (NO). Nevertheless, the data also indicated that prospective biomarkers of effect are gaining ground and a guiding representation of the established and novel biomarkers is suggested for upcoming trials. Finally, potential protective strategies to mitigate the adverse effects of specific toxicants are underlined for future studies.

The role of B cell metabolism in autoimmune diseases

B cells are major players in immune responses being the source of protective antibodies and antigen presenting cells. When self-tolerance fails, auto reactive B cells produce autoantibodies and pro-inflammatory cytokines leading to the development of autoimmune diseases. Many recent studies have assessed importance of metabolic pathways in B cells, demonstrating their role in controlling autoimmunity and maintaining immune homeostasis. Alterations in B cell functions in autoimmune diseases are closely associated with abnormal metabolic shifts, allowing auto reactive B cells to escape tolerogenic checkpoints. Understanding the metabolic changes in B cells, opens up new possibilities for targeting metabolic pathways and manipulating metabolic avenues as a therapeutic strategy for the treatment of autoimmune diseases.

Biocompatibility and Antioxidant Capabilities of Carbon Dots Obtained from Tomato (Solanum lycopersicum)

Since their discovery in 2004, carbon dots have attracted strong interest in the scientific community due to their characteristic properties, particularly their luminescence and their ease of synthesis and derivatization. Carbon dots can be obtained from different carbon sources, including natural products, resulting in a so-called ’green synthesis’. In this work, we obtain carbon dots from tomato juice in order to obtain nanoparticles with the antioxidant capabilities of the natural antioxidants present in that fruit. The obtained material is characterized regarding nanoparticle size distribution, morphology, surface functional groups and optic properties. Antioxidant properties are also evaluated through the DPPH method and their cytotoxicity is checked against human dermal fibroblast and A549 cell-lines. The results indicate that carbon dots obtained from tomato have a higher antioxidant power than other already-published antioxidant carbon dots. The bandgap of the synthesized materials was also estimated and coherent with the literature values. Moreover, carbon dots obtained from tomato juice are barely toxic for healthy cells up to 72 h, while they induce a certain cytotoxicity in A549 lung carcinoma cells.

Shortage of aspartate in mitochondria fuels arthritis

In patients with rheumatoid arthritis, a short supply of aspartate in the mitochondria can force the endoplasmic reticulum of T cells to generate transmembrane TNF, which in turn contributes to synovial inflammation.