1,25-dihydroxyvitamin D3 ameliorates lupus nephritis through inhibiting the NF-κB and MAPK signalling pathways in MRL/lpr mice

Injectable hydrogel microsphere orchestrates immune regulation and bone regeneration via sustained release of calcitriol

Repairing bone defects in inflammatory conditions remains a significant clinical challenge. An ideal scaffold material for such situations should enable minimally invasive implantation and integrate capabilities for immunomodulation, anti-infection therapy, and enhanced bone regeneration. In this study, we developed injectable calcitriol@polydopamine@gelatin methacryloyl hydrogel microspheres (CAL@PDA@GMs) using microfluidic technology. This system facilitates the sustained release of calcitriol, which features excellent biocompatibility and biodegradability, promotes osteogenesis, scavenges excessive reactive oxygen species (ROS), and induces the polarization of macrophages from the M1 to M2 phenotype, thereby mitigating lipopolysaccharide (LPS)-induced inflammation. These mechanisms work synergistically to create an optimal immune microenvironment for bone regeneration in inflammatory conditions. RNA sequencing (RNA-Seq) analyses revealed that immunomodulation is achieved by regulating macrophage phenotypes, inhibiting the nuclear transcription factor-kappa B (NF-κB) and ROS signaling pathways, and reducing the secretion of pro-inflammatory cytokines. This study proposes a novel method to enhance tissue regeneration by remediating the damaged tissue microenvironment and presents a potential clinical therapeutic strategy for large-scale bone injuries.

Identification of serum exosomal miRNA biomarkers in patients with lupus nephritis

INTRODUCTION

Characterized by glomerulonephritis, lupus nephritis (LN) worsens the prognosis of patients with systemic lupus erythematosus (SLE) and contributes to its increased mortality rate. Here, we investigated whether serum exosomal microRNAs (miRNAs) are promising new biomarkers of LN.

METHODS

Serum exosomes were initially isolated using a reagent-based kit, and total RNA was extracted with the Trizol method. Small RNA sequencing was subsequently performed to identify differentially expressed exosomal miRNAs. Validation of these miRNAs was conducted via real-time quantitative polymerase chain reaction (RT-qPCR) on individual samples from both the training and validation cohorts, leading to the identification of candidate small RNAs specifically associated with LN. Receiver operating characteristic (ROC) curve analysis was employed to evaluate the diagnostic performance of the identified candidates. To further investigate the immune landscape, 12 types of cytokines were quantified using flow cytometry, and their correlations with the candidate miRNAs were analyzed via Spearman rank correlation. Additionally, the biological functions of these miRNAs were explored through enrichment analyses based on Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways.

RESULTS

The levels of hsa-miR-497-5p and hsa-miR-6515-5p were significantly higher in the LN group compared to the SLE without LN group, with a combined area under the ROC curve (AUC) of 0.798. Notably, these two miRNAs demonstrated exceptional discriminative performance in identifying LN patients with mild proteinuria, achieving an AUC of 0.844. Furthermore, flow cytometry analysis revealed markedly elevated serum levels of interferon (IFN)-γ, interleukin (IL)-8, and IL-17 in the LN group compared to healthy controls (HCs). Additionally, IL-6 and IL-17 levels were significantly higher in the LN group compared to the SLE without LN group. Hsa-miR-6515-5p exhibited a strong positive correlation with IL-8 and IFN-γ. Bioinformatic analyses indicated that these exosomal miRNAs may contribute to the progression of LN by regulating key signaling pathways, with the MAPK signaling pathway being prominently implicated.

CONCLUSIONS

Our study demonstrated that serum exosomal miRNAs, specifically hsa-miR-497-5p and hsa-miR-6515-5p, show significant potential as biomarkers for the early detection and prognosis of LN.

Identification of cellular senescence-related genes as biomarkers for lupus nephritis based on bioinformatics

Background

Lupus nephritis (LN) is one of the most common and severe complications of systemic lupus erythematosus with unclear pathogenesis. The most accurate diagnosis criterion of LN is still renal biopsy and nowadays treatment strategies of LN are far from satisfactory. Cellular senescence is defined as the permanent cell cycle arrest marked by senescence-associated secretory phenotype (SASP), which has been proved to accelerate the mobility and mortality of patients with LN. The study is aimed to identify cellular senescence-related genes for LN.

Methods

Genes related to cellular senescence and LN were obtained from the MSigDB genetic database and GEO database respectively. Through differential gene analysis, Weighted Gene Go-expression Network Analysis (WGCNA) and machine learning algorithms, hub cellular senescence-related differentially expressed genes (CS-DEGs) were identified. By external validation, hub CS-DEGs were further filtered and the remaining genes were identified as biomarkers. We explored their potential physiopathologic function through GSEA.

Results

We obtained 432 genes related to cellular senescence, 1,208 differentially expressed genes (DEGs) and 840 genes in the key gene module related to LN, which were intersected with each other for CS-DEGs. Subsequent Machine learning algorithms screened out six hub CS-DEGs and finally three hub CS-DEGs, ALOX5, PTGER2 and PRKCB passed through external validation, which were identified as biomarkers. The three biomarkers were enriched in "B Cell receptor signaling pathway" and "NF-kappa B signaling pathway" based on GESA results.

Conclusion

This study explored the potential relationship between cellular senescence and LN, and identified three biomarkers ALOX5, PTGER2, and PRKCB playing key roles in LN, which will provide new insights for the diagnosis and treatment of LN.

Lanatoside C Inhibits Proliferation and Induces Apoptosis in Human Prostate Cancer Cells Through the TNF/IL-17 Signaling Pathway

Prostate cancer remains a leading cause of cancer-related morbidity and mortality among men globally, with limited therapeutic options for advanced and metastatic disease. The therapeutic potential of natural compounds has attracted increasing attention in cancer treatment. Lanatoside C (Lan C), a cardiac glycoside derived from Digitalis lanata, has demonstrated promising anticancer activity across various cancer types. However, its role and mechanisms in prostate cancer remain underexplored. In this study, evidence shows that Lan C significantly inhibits the proliferation of prostate cancer cells, as demonstrated by reduced cell viability, suppressed colony formation, and G2/M cell cycle arrest. Additionally, Lan C promotes apoptosis and inhibits the migration and invasion of prostate cancer cells. Mechanistically, transcriptomic analysis identified differentially expressed genes, which were further validated at both the mRNA and protein levels. Our findings suggest that Lan C exerts its effects by modulating the TNF/IL-17 signaling pathway, influencing the tumor microenvironment and regulating key processes involved in tumor progression, immune response, and apoptosis.

The immunomodulatory potential of vitamin D on Th17 lymphocytes in systemic lupus erythematosus - a literature review

This review offers insight into the complex interplay between cytokines and vitamin D, with focus on its role in systemic lupus erythematosus (SLE) pathogenesis. It offers a helpful resource for researchers and clinicians seeking to better understand and treat SLE and related autoimmune conditions. The pathogenesis of SLE is complex and involves a wide range of cytokines, primarily of the Th2 type; these cytokines mediate hyperactivity in B lymphocytes and antibody production. Notably, vitamin D is found to suppress the activity of critical Th17-related cytokines like IL-23 and IL-6, which is pivotal for Th17 cell development and function. This ultimately leads to reduced IL-17 production, an increase in regulatory T lymphocytes, and subsequent secretion of IL-10. Supplementation with vitamin D is seen to have positive effects on SLE, leading to lower disease activity scores, decreased levels of autoantibodies, and a reduction of fatigue.

HDAC6 promotes inflammation in lupus nephritis mice by regulating transcription factors MAFF and KLF5 in renal fibrosis

AIM

This study explored the effect and mechanism of MAFF and HDAC6 on renal fibrosis and inflammation in lupus nephritis (LN).

METHODS

IL-33 treated renal epithelial cells and MRL/lpr mice were respectively used for in vitro and in vivo experiments. The expressions of HDAC6, MAFF, and KLF5 were measured in cells and renal tissues. Before and after cell transfection, the morphological changes in renal tissues were observed using Hematoxylin and eosin (H&E) and Masson staining. The proteinuria, serum creatinine (SCr), blood urea nitrogen (BUN), and double-stranded DNA (dsDNA) levels were detected by biochemical analysis. The expressions of fibrosis and inflammation related proteins (including α-SMA, Vimentin, IL-1β, IL-6, and TNF-α), p65, and iNOS were also detected. The relationship among MAFF, HDAC6, and KLF5 was determined by chromatin immunoprecipitation and dual luciferase reporter gene assay.

RESULTS

Renal tissues and cell models had elevated expressions of HDAC6 and KLF5, and decreased MAFF expression. HDAC6 suppression or MAFF overexpression led to suppression of proteinuria, SCr, BUN, and dsDNA levels, as well as attenuation of inflammatory infiltration and collagen deposition. HDAC6 can suppress MAFF expression via deacetylation to abolish its suppression of KLF5 expression, thus increasing KLF5 expression. In vivo and in vitro experiments showed the suppressive effect of HDAC6 suppression on renal fibrosis and inflammation can be abolished by KLF5 overexpression.

CONCLUSION

HDAC6 suppresses MAFF expression via deacetylation to elevate KLF5 expression, which consequently enhances fibrosis and inflammatory response in LN.

Putative mechanism of a multivitamin treatment against insulin resistance

Insulin resistance is caused by the abnormal secretion of proinflammatory cytokines in adipose tissue, which is induced by an increase in lipid accumulation in adipocytes, hepatocytes, and myocytes. The inflammatory pathway involves multiple targets such as nuclear factor kappa B, inhibitor of nuclear factor κ-B kinase, and mitogen-activated protein kinase. Vitamins are micronutrients with anti-inflammatory activities that have unclear mechanisms. The present study aimed to describe the putative mechanisms of vitamins involved in the inflammatory pathway of insulin resistance. The strategy to achieve this goal was to integrate data mining and analysis, target prediction, and molecular docking simulation calculations to support our hypotheses. Our results suggest that the multitarget activity of vitamins A, B1, B2, B3, B5, B6, B7, B12, C, D3, and E inhibits nuclear factor kappa B and mitogen-activated protein kinase, in addition to vitamins A and B12 against inhibitor of nuclear factor κ-B kinase. The findings of this study highlight the pharmacological potential of using an anti-inflammatory and multitarget treatment based on vitamins and open new perspectives to evaluate the inhibitory activity of vitamins against nuclear factor kappa B, mitogen-activated protein kinase, and inhibitor of nuclear factor κ-B kinase in an insulin-resistant context.

Prevalence and risk factors of osteoporosis in lupus nephritis patients in China: a cross-sectional study

BACKGROUND

Osteoporosis is a significant concern among individuals with lupus nephritis (LN), with reported prevalence rates exhibiting considerable variation. This study investigates the prevalence and identifies risk factors contributing to osteoporosis in premenopausal and postmenopausal LN patients, addressing the paucity of data specific to the Chinese population.

METHODS

This cross-sectional study enrolled patients with renal biopsy-proven LN, who underwent bone mineral density (BMD) measurements using dual X-ray absorptiometry at the lumbar spine, total hip, and femoral neck. The study was conducted at Tongji hospital from May 2011 to June 2018.

RESULTS

A total of 130 patients were evaluated, with a mean age of 46.2 ± 12.9 years, including 2 males and 128 females. A significant majority, 52.3% (n = 67) of the female patients, were identified as postmenopausal. BMD measurements revealed that 40.0% of patients had osteoporosis in at least one site. The spearman rank correlation of BMD with clinical characteristics indicated that age at menopause, weight, height, and body mass index were positively correlated with BMD, while age, age at diagnosis of LN, and menopause duration were negatively correlated with BMD in lumbar spine, total hip, and/or femoral neck. Multivariable linear regression analysis demonstrated that body mass index was positively associated with BMD, whereas disease duration and menopause duration were negatively associated with BMD in all and postmenopausal patients. Postmenopausal patients consistently had a higher prevalence of osteoporosis across all measured sites. Factors such as older age, lower weight, and the absence of bisphosphonates therapy were independently associated with an increased risk of osteoporosis in LN patients.

CONCLUSION

Our findings underscore a substantial prevalence of osteoporosis in LN patients, especially among postmenopausal individuals. The study identifies older age, lower weight, and absence of bisphosphonates treatment as risk factors for osteoporosis in this patient population.

Islet cell spheroids produced by a thermally sensitive scaffold: a new diabetes treatment

The primary issues in treating type 1 diabetes mellitus (T1DM) through the transplantation of healthy islets or islet β-cells are graft rejection and a lack of available donors. Currently, the majority of approaches use cell encapsulation technology and transplant replacement cells that can release insulin to address transplant rejection and donor shortages. However, existing encapsulation materials merely serve as carriers for islet cell growth. A new treatment approach for T1DM could be developed by creating a smart responsive material that encourages the formation of islet cell spheroids to replicate their 3D connections in vivo and controls the release of insulin aggregates. In this study, we used microfluidics to create thermally sensitive porous scaffolds made of poly(N-isopropyl acrylamide)/graphene oxide (PNIPAM/GO). The material was carefully shrunk under near-infrared light, enriched with mouse insulinoma pancreatic β cells (β-TC-6 cells), encapsulated, and cultivated to form 3D cell spheroids. The controlled contraction of the thermally responsive porous scaffold regulated insulin release from the spheroids, demonstrated using the glucose-stimulated insulin release assay (GSIS), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence assay. Eventually, implantation of the spheroids into C57BL/6 N diabetic mice enhanced the therapeutic effect, potentially offering a novel approach to the management of T1DM.

Vitamin D and systemic lupus erythematosus: Causality and association with disease activity and therapeutics

The major role of bioactive vitamin 1,25-dihydroxyvitamin D3 (1,25(OH)2D or calcitriol) is to maintain the levels of calcium and phosphorus to achieve bone and mineral homeostasis. Dietary intake and adequate natural light exposure are the main contributors to normal vitamin D status. In addition to regulating metabolism, vitamin D exerts various immunomodulatory effects that regulate innate and adaptive immunity through immune effector cells such as monocytes, macrophages, T and B lymphocytes, and natural killer cells and nonimmune cells that express vitamin D receptors. Systemic lupus erythematosus (SLE) is an autoimmune disease with an unknown etiology, and the association between vitamin D and SLE remains incompletely understood. Given that the current treatment for SLE relies heavily on corticosteroids and that SLE patients tend to have low vitamin D status, vitamin D supplementation may help to reduce the dosage of corticosteroids and/or attenuate disease severity. In this review, we address the associations between vitamin D and several clinical aspects of SLE. In addition, the underlying immunomodulatory mechanisms accounting for the potential vitamin D-mediated therapeutic effects are discussed. Finally, several confounding factors in data interpretation and the execution of clinical trials and perspectives targeting vitamin D supplementation in patients with SLE are also addressed.

Paricalcitol prevents MAPK pathway activation and inflammation in adriamycin-induced kidney injury in rats

BACKGROUND

Activation of the mitogen-activated protein kinase (MAPK) pathway induces uncontrolled cell proliferation in response to inflammatory stimuli. Adriamycin (ADR)-induced nephropathy (ADRN) in rats triggers MAPK activation and pro-inflammatory mechanisms by increasing cytokine secretion, similar to chronic kidney disease (CKD). Activation of the vitamin D receptor (VDR) plays a crucial role in suppressing the expression of inflammatory markers in the kidney and may contribute to reducing cellular proliferation. This study evaluated the effect of pre-treatment with paricalcitol on ADRN in renal inflammation mechanisms.

METHODS

Male Sprague-Dawley rats were implanted with an osmotic minipump containing activated vitamin D (paricalcitol, Zemplar, 6 ng/day) or vehicle (NaCl 0.9%). Two days after implantation, ADR (Fauldoxo, 3.5 mg/kg) or vehicle (NaCl 0.9%) was injected. The rats were divided into four experimental groups: control, n = 6; paricalcitol, n = 6; ADR, n = 7 and, ADR + paricalcitol, n = 7.

RESULTS

VDR activation was demonstrated by increased CYP24A1 in renal tissue. Paricalcitol prevented macrophage infiltration in the glomeruli, cortex, and outer medulla, prevented secretion of tumor necrosis factor-α, and interleukin-1β, increased arginase I and decreased arginase II tissue expressions, effects associated with attenuation of MAPK pathways, increased zonula occludens-1, and reduced cell proliferation associated with proliferating cell nuclear antigen expression. Paricalcitol treatment decreased the stromal cell-derived factor 1α/chemokine C-X-C receptor type 4/β-catenin pathway.

CONCLUSIONS

Paricalcitol plays a renoprotective role by modulating renal inflammation and cell proliferation. These results highlight potential targets for treating CKD.

Silencing HE4 alleviates the renal fibrosis in lupus nephritis mice by regulating the C3/MMPs/prss axis

To explore the regulatory effect of human epididymis protein 4 (HE4) on renal fibrosis in mice with lupus nephritis (LN) and the underlying mechanism. Ten-week old MRL/LPR mice were injected with HE4 shRNA adenovirus vector through the renal pelvis for 5 days. Renal tissues were extracted for HE and Masson staining to evaluate pathological changes and fibrosis in lupus nephritis mice. The level of urine protein was measured using a biochemical analyzer, while the expression level of HE4 and p-NF-κB p65 in renal tissues was visualized using an immunofluorescence assay. The level of β2-microglobulin (β2-MG), neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecule 1 (Kim-1) was determined by the immunohistochemical assay. Western blotting was used to determine the levels of C3, HE4, matrix metalloproteinase-2 (MMP2), MMP9, p-p65, prss23, and prss35 in renal tissues. Compared to wild-type C57BL/6 mice, MRL/LPR mice showed a marked increase in the number of glomeruli, hyperplasic basement membrane, severe infiltration of inflammatory cells in renal tubules and glomeruli, obvious necrosis in glomeruli, elevated fibrosis levels, and increased levels of urine protein, β2-MG, NGAL, Kim-1, C3, HE4, MMP2, MMP9, and p-p65; and decreased levels of prss23 and prss35 were observed in MRL/LPR mice. After the administration of the HE4 shRNA adenovirus vector, the repaired structure of renal tubules and glomeruli improved infiltration of inflammatory cells, reduced collagen fiber and urine protein, suppressed levels of C3, HE4, MMP2, MMP9, and p-P65, and facilitated the expression of prss23 and prss35 which were observed. Silencing HE4 improved renal fibrosis and inhibited inflammation in mice with lupus nephritis, which may play a role in inhibiting C3/MMPs and promoting prss-related protein expression.

Inflammasome Molecular Insights in Autoimmune Diseases

Autoimmune diseases (AIDs) emerge due to an irregular immune response towards self- and non-self-antigens. Inflammation commonly accompanies these conditions, with inflammatory factors and inflammasomes playing pivotal roles in their progression. Key concepts in molecular biology, inflammation, and molecular mimicry are crucial to understanding AID development. Exposure to foreign antigens can cause inflammation, potentially leading to AIDs through molecular mimicry triggered by cross-reactive epitopes. Molecular mimicry emerges as a key mechanism by which infectious or chemical agents trigger autoimmunity. In certain susceptible individuals, autoreactive T or B cells may be activated by a foreign antigen due to resemblances between foreign and self-peptides. Chronic inflammation, typically driven by abnormal immune responses, is strongly associated with AID pathogenesis. Inflammasomes, which are vital cytosolic multiprotein complexes assembled in response to infections and stress, are crucial to activating inflammatory processes in macrophages. Chronic inflammation, characterized by prolonged tissue injury and repair cycles, can significantly damage tissues, thereby increasing the risk of AIDs. Inhibiting inflammasomes, particularly in autoinflammatory disorders, has garnered significant interest, with pharmaceutical advancements targeting cytokines and inflammasomes showing promise in AID management.

MicroRNA miR-181d-5p regulates the MAPK signaling pathway by targeting mitogen-activated protein kinase 8 (MAPK8) to improve lupus nephritis

BACKGROUND

Lupus nephritis (LN) is a common immune disease. The microRNA (miR)-181d-5p is a potential target for treating kidney injury. However, the therapeutic role of miR-181d-5p in LN has not been investigated. This study aimed to investigate the role of miR-181d-5p in targeting mitogen-activated protein kinase 8 (MAPK8) and stimulating the MAPK signaling pathway in LN.

METHODS

RT-qPCR was performed to identify the variations in miR-181d-5p expression in peripheral blood mononuclear cells (PBMCs) obtained from 42 LN patients, 30 healthy individuals, 6 MRL/lpr mice and 6 C57BL/6 mice. Western blot was used to detect the effect of miR-181d-5p on the MAPK signaling pathway in THP-1 cells and MRL/lpr mice. Enzyme-linked immunosorbent assay (ELISA) was utilized to detect the effect of miR-181d-5p on antinuclear antibodies and inflammatory factors. A dual-luciferase reporter assay was used to verify whether miR-181d-5p directly targets MAPK8. Flow cytometry was performed to evaluate apoptosis rates in transfected THP-1 cells.

RESULTS

miR-181d-5p expression was downregulated in PBMCs of LN patients (P < 0.01) and MRL/lpr mice (P < 0.05). A dual luciferase reporter assay demonstrated that miR-181d-5p inhibits MAPK8 (P < 0.01). Overexpression of miR-181d-5p inhibited the phosphorylation of p38 (P < 0.001) and p44/42 (P < 0.01). Moreover, miR-181d-5p decreased the apoptosis rate of THP-1 cells (P < 0.001), and reduced the secretion of IL-6 (P < 0.01) and TNF-α (P < 0.01). Furthermore, overexpression of miR-181d-5p decreased anti-dsDNA antibody (P < 0.05), anti-Sm antibody (P < 0.01), and fibrosis levels in MRL/lpr mice.

CONCLUSION

Upregulation of miR-181d-5p showed anti-inflammatory and anti-apoptotic effects on THP-1 cells in vitro and kidney injury in vivo. These effects were achieved by miR-181d-5p targeting MAPK8 to inhibit phosphorylation of p38 and p44/42. These results may offer new insights for improving therapeutic strategies against lupus nephritis.

C/EBPβ isoform-specific regulation of podocyte pyroptosis in lupus nephritis-induced renal injury

As an essential factor in the prognosis of systemic lupus erythematosus (SLE), lupus nephritis (LN) can accelerate the rate at which patients with SLE can transition to chronic kidney disease or even end-stage renal disease. Podocytes now appear to be a possible direct target in LN in addition to being prone to collateral damage from glomerular capillary lesions induces by immune complexes and inflammatory processes. The NLRP3 inflammasome is regulated by CCAAT/enhancer-binding protein β (C/EBPβ), which is involved in the pathogenesis of SLE. However, the role and mechanism of C/EBPβ in LN remain unclear. In this investigation, glomerular podocytes treated with LN serum and MRL/lpr mice were employed as in vivo and in vitro models of LN, respectively. In vivo, the expression of C/EBPβ isoforms was detected in kidney specimens of humans and mice with LN. Then we assessed the effect of C/EBPβ inhibition on renal structure and function by injecting RNAi adeno-associated virus of C/EBPβ shRNA into MRL/lpr mice. In vitro, glomerular podocytes were treated with LN serum and C/EBPβ siRNA to explore the role of C/EBPβ in the activation of the AIM2 inflammasome and podocyte injury. C/EBPβ-LAP and C/EBPβ-LIP were significantly overexpressed in kidney tissue samples from LN patients and mice, and C/EBPβ inhibition significantly alleviated renal function damage and ameliorated renal structural deficiencies. Inflammatory pathways downstream from the AIM2 inflammasome could be suppressed by C/EBPβ knockdown. Furthermore, the upregulation of C/EBPβ-LAP could activate the AIM2 inflammasome and podocyte pyroptosis by binding to the promoters of AIM2 and CASPASE1 to enhance their expression, and the knockdown of AIM2 or (and) caspase-1 reversed the effects of C/EBPβ-LAP overexpression. Interestingly, C/EBPβ-LIP overexpression could transcriptionally inhibit IRAG and promote Ca2+ release-mediated activation of the AIM2 inflammasome. This finding suggests that C/EBPβ is not only involved in the regulation of the expression of key proteins of the AIM2 inflammasome but also affects the polymerization of key proteins of the AIM2 inflammasome through the regulation of Ca2+ release. In conclusion, this study provides a new idea for studying the regulatory mechanism of C/EBPβ and provides a theoretical basis for the early diagnosis and treatment of LN in the future. © 2023 The Pathological Society of Great Britain and Ireland.

New Potentiality of Bioactive Substances: Regulating the NLRP3 Inflammasome in Autoimmune Diseases

The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is an essential component of the human innate immune system, and is closely associated with adaptive immunity. In most cases, the activation of the NLRP3 inflammasome requires priming and activating, which are influenced by various ion flux signals and regulated by various enzymes. Aberrant functions of intracellular NLRP3 inflammasomes promote the occurrence and development of autoimmune diseases, with the majority of studies currently focused on rheumatoid arthritis, systemic lupus erythematosus and systemic sclerosis. In recent years, a number of bioactive substances have shown new potentiality for regulating the NLRP3 inflammasome in autoimmune diseases. This review provides a concise overview of the composition, functions, and regulation of the NLRP3 inflammasome. Additionally, we focus on the newly discovered bioactive substances for regulating the NLRP3 inflammasome in autoimmune diseases in the past three years.

Effects of Dietary Oleacein Treatment on Endothelial Dysfunction and Lupus Nephritis in Balb/C Pristane-Induced Mice

Systemic lupus erythematosus (SLE) is a chronic immune-inflammatory disease characterized by multiorgan affectation and lowered self-tolerance. Additionally, epigenetic changes have been described as playing a pivotal role in SLE. This work aims to assess the effects of oleacein (OLA), one of the main extra virgin olive oil secoiridoids, when used to supplement the diet of a murine pristane-induced SLE model. In the study, 12-week-old female BALB/c mice were injected with pristane and fed with an OLA-enriched diet (0.01 % (w/w)) for 24 weeks. The presence of immune complexes was evaluated by immunohistochemistry and immunofluorescence. Endothelial dysfunction was studied in thoracic aortas. Signaling pathways and oxidative-inflammatory-related mediators were evaluated by Western blotting. Moreover, we studied epigenetic changes such as DNA methyltransferase (DNMT-1) and micro(mi)RNAs expression in renal tissue. Nutritional treatment with OLA reduced the deposition of immune complexes, ameliorating kidney damage. These protective effects could be related to the modulation of mitogen-activated protein kinases, the Janus kinase/signal transducer and transcription activator of transcription, nuclear factor kappa, nuclear-factor-erythroid-2-related factor 2, inflammasome signaling pathways, and the regulation of miRNAs (miRNA-126, miRNA-146a, miRNA-24-3p, and miRNA-123) and DNMT-1 expression. Moreover, the OLA-enriched diet normalized endothelial nitric oxide synthase and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-1 overexpression. These preliminary results suggest that an OLA-supplemented diet could constitute a new alternative nutraceutical therapy in the management of SLE, supporting this compound as a novel epigenetic modulator of the immunoinflammatory response.