Treatment with lysophosphatidic acid improves glomerulonephritis through the suppression of macrophage activation in a murine model of systemic lupus erythematosus.

OBJECTIVES: Several therapeutic agents have been developed and used for the clinical treatment of systemic lupus erythematosus (SLE). In cases where SLE is accompanied by severe organ failures, such as neuropsychiatric lupus erythematosus (NPSLE) and acute onset of lupus nephritis, the use of potent immunosuppressive drugs, such as cyclophosphamide, is necessary. However, potent immunosuppressive drugs are known to increase infection risks. Thus, the development of therapeutic agents with novel mechanisms is urgently required. Previously, we reported that treatment with lysophosphatidic acid (LPA) prevents depression-like behaviours by suppressing microglial activation in MRL/lpr mice. In this study, we examined whether the treatment with LPA improves glomerulonephritis by affecting systemic immunity in MRL/lpr mice. METHODS: Eighteen-week-old MRL/lpr mice were treated with a vehicle or LPA for 3 weeks. After treatment, the glomerular inflammation and damage parameters were compared between the 2 groups. Moreover, we examined the effects of LPA on immune cells by flow cytometry using isolated splenocytes. RESULTS: LPA treatment in MRL/lpr mice significantly reduced the daily urinary albumin content and suppressed the CD68-positive cells and Periodic acid-Schiff (PAS)-positive areas in the glomeruli. The treatment also suppressed plasma anti-dsDNA antibodies and inflammatory cytokines in MRL/lpr mice. Although LPA did not significantly affect the total number of splenocytes, the treatment significantly reduced CD11b+Ly6G-Ly6C- cells (mature macrophages), as well as CD11b+Ly6G-Ly6C-CD68+ cells (activated mature macrophages). CONCLUSIONS: These results suggest that LPA may improve glomerulonephritis by suppressing macrophage activation in MRL/lpr mice.

Systematic review and meta-analysis for the 2024 update of the Japan College of Rheumatology clinical practice guidelines for the management of rheumatoid arthritis.

OBJECTIVES: To update evidence on the efficacy and safety of disease-modifying antirheumatic drugs (DMARDs) and provide information to the taskforce for the 2024 update of the Japan College of Rheumatology (JCR) clinical practice guidelines (CPG) for the management of rheumatoid arthritis (RA). METHODS: We searched various databases for randomised controlled trials on RA published until June 2022, with no language restriction. For each of the 15 clinical questions, 2 independent reviewers screened the articles, evaluated the core outcomes, and performed meta-analyses. RESULTS: Subcutaneous injection of methotrexate (MTX) showed similar efficacy to oral MTX in MTX-naïve RA patients. Ozoralizumab combined with MTX improved drug efficacy compared to the placebo in RA patients with inadequate response (IR) to csDMARD. Rituximab with and without concomitant csDMARDs showed similar efficacy to other bDMARDs in bDMARD-IR RA patients. Combined Janus kinase inhibitors and MTX achieved similar clinical responses and equal safety during a 4-year period compared to tumour necrosis factor inhibitors in MTX-IR RA patients. Biosimilars showed efficacy equivalent to that of the original bDMARDs in csDMARD-IR and bDMARD-IR RA patients. CONCLUSION: This systematic review provides latest evidence for the 2024 update of the JCR CPG for RA management.

Treatment with lysophosphatidic acid prevents microglial activation and depression-like behaviours in a murine model of neuropsychiatric systemic lupus erythematosus.

Neuropsychiatric systemic lupus erythematosus (NPSLE) is an incurable disease characterised by neuropsychiatric symptoms, particularly depression. Novel therapeutic options for NPSLE are urgently needed. Several previous reports have suggested that both microglial activation and impaired neurogenesis may be involved in the progression of depression. In contrast, the administration of lysophosphatidic acid (LPA) ameliorates depression and anxiety. Therefore, in the present study, we determined whether treatment with LPA affects microglial activation, impaired neurogenesis, and abnormal behaviour in MRL/lpr mice. In both tail suspension test and forced swim test, the MRL/lpr mice exhibited a significant increase in total immobility time compared with MRL/+ mice. Treatment with LPA significantly suppressed the prolonged immobility time in MRL/lpr mice. In contrast, pretreatment with ki16425 (a specific antagonist of LPA receptor 1 and 3) significantly reversed the effects of LPA. Furthermore, MRL/lpr mice exhibited impairments in spatial working memory and visual cognitive memory, which were suppressed by LPA treatment. The expression levels of TMEM119, CD68, GFAP, and caspase-3 in the hippocampus and prefrontal cortex of MRL/lpr mice were significantly higher than those in MRL/+ mice. Treatment with LPA inhibited these increases in MRL/lpr mice. Pretreatment with ki16425 reversed LPA-mediated inhibition of microglial activation. The quantity of sodium fluorescein that leaked into the brain tissues in MRL/lpr mice were significantly higher than that in MRL/+ mice. Treatment with LPA tended to decrease the sodium fluorescein leakage. These findings suggest that treatment with LPA may regulate microglial activation, which is important in the pathogenesis of NPSLE, as well as blood-brain-barrier weakening and abnormal behaviour.

Intensity Interference in a Coherent Spin-Polarized Electron Beam.

We investigate the intensity interference between pairs of electrons using a spin-polarized electron beam having a high polarization and a narrow energy width. We observe spin-dependent antibunching on the basis of coincident counts of electron pairs performed with a spin-polarized transmission electron microscope, which could control the spin-polarization without any changes in the electron optics. The experimental results show that the time correlation was only affected by the spin polarization, demonstrating that the antibunching is associated with fermionic statistics. The coherent spin-polarized electron beam facilitates the extraction of intrinsic quantum interference.

A preliminary therapeutic study of the effects of molecular hydrogen on intestinal dysbiosis and small intestinal injury in high-fat diet-loaded senescence-accelerated mice.

OBJECTIVES: Aging and excessive fat intake may additively induce dysbiosis of the gut microbiota and intestinal inflammatory damage. Here, we analyzed microbiota dysbiosis and intestinal injury in high-fat diet-loaded senescence-accelerated mice (SAMP8). Additionally, we examined whether treatment with molecular hydrogen could improve the intestinal environment. METHODS: SAMP8 and SAMR1 (control) mice were first fed a normal diet (ND) or high-fat diet (HFD) for 10 wk (n = 10 each group). Subsequently, HFD was supplemented with a placebo jelly or hydrogen-rich jelly (HRJ) for 4 wk. After treatment, isolated small intestinal tissues were used for hematoxylin and eosin staining, immunofluorescence staining, and thiobarbituric acid reactive substances (TBARS) assay. Furthermore, we analyzed alterations in the microbiota composition in cecal feces using 16S rRNA gene analysis for microbiota profiling. Statistical analyses were performed using unpaired Student's t tests or one-way analysis of variance and Tukey's post hoc test for multiple comparisons. RESULT: HFD feeding reduced the expression of caudal-related homeobox transcription factor 2 (CDX2) and 5-bromo-2'-deoxyuridine (BrdU) and enhanced malondialdehyde (MDA) levels in the small intestine of SAMP8. HRJ treatment improved the reduction in CDX2 and BrdU and enhanced MDA levels. We performed a sequence analysis of the gut microbiota at the genus level and identified 283 different bacterial genera from the 30 samples analyzed in the study. Among them, Parvibacter positively correlated with both HFD intake and aging, whereas 10 bacteria, including Anaerofustis, Anaerosporobacter, Butyricicoccus, and Ruminococcus were negatively correlated with both HFD and aging. HRJ treatment increased Lactinobactor and decreased Akkermansia, Gracilibacter, and Marvinbryantia abundance. CONCLUSION: Our findings suggest that treatment with molecular hydrogen may affect microbiota profiling and suppress intestinal injury in HFD-loaded SAMP8.

Two-carba cyclic phosphatidic acid treatment promotes phenotypic switch from M1 to M2 microglia and prevents behavioral abnormalities in a mouse model of neuropsychiatric systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with the production of double-stranded DNA (dsDNA) antibodies and other antibodies that predominantly affects women with a wide range of lesions. Although neuropsychiatric lupus erythematosus (NPSLE), characterized by neuropsychiatric symptoms related to cerebrovascular diseases or depression, ranks high in severity, no specific treatment has been defined. Two-carba cyclic phosphatidic acid (2ccPA), a derivative of cyclic phosphatidic acid, was isolated from the true slime mold Physarum polycephalum in 1992. 2ccPA treatment suppresses neuroinflammation and promotes tissue repair in mouse multiple sclerosis and traumatic brain injury models. In this study, we performed behavioral tests on MRL/lpr mice as an NPSLE model. MRL/lpr mice showed increased depression-like behaviors compared with control mice, which were significantly suppressed by 2ccPA treatment. The expression of CD68, an M1 phenotypic marker of microglia, was significantly elevated in the prefrontal cortex and hippocampus of MRL/lpr mice, which was significantly suppressed by 2ccPA treatment. In contrast, the expression of Arginase1, an M2 phenotypic marker of microglia, was significantly increased by 2ccPA treatment. Compared to control mice, MRL/lpr mice showed higher plasma levels of anti-dsDNA antibodies, which are mainly involved in SLE pathogenesis. 2ccPA treatment decreased these levels in the MRL/lpr mice. These results suggest that 2ccPA treatment suppresses behavioral abnormalities by promoting a microglial phenotypic switch from M1 to M2 in MRL/lpr mice.

Effects of oxidized low-density lipoprotein on differentiation of mouse neural progenitor cells into neural cells.

In Alzheimer's disease (AD), a decline in function of neural progenitor cells (NPCs) results in a reduced capacity for neural regeneration. It has been shown that plasma oxidized low-density lipoprotein (ox-LDL) levels are positively correlated with severity in patients with AD. However, the direct effects of ox-LDL on NPCs are unknown. Thus, we examined the effects of ox-LDL on the proliferation and differentiation of mouse NPCs into neural cells. Mouse induced pluripotent stem (iPS) cell-derived embryoid bodies were stimulated with Noggin and SB431542 for 4 days. Mouse NPCs were then collected using anti-polysialic acid-neural cell adhesion molecule antibodies in a magnetic separator. The proliferation of mouse NPCs was examined using the MTT assay. The differentiation of mouse NPCs into neural cells was examined by the expression of NeuN (a neuronal-specific nuclear protein) using immunofluorescence staining and Western blot analysis. Treatment with ox-LDL did not affect the proliferation of mouse NPCs. While treatment with all-trans retinoic acid (ATRA), epidermal growth factor (EGF), and basic fibroblast growth factor (FGF) significantly induced NeuN expression in the differentiated NPCs (P < 0.01), the addition of ox-LDL significantly inhibited the NeuN expression (P < 0.05). Pretreatment with SC-79 (an Akt activator) significantly reversed the inhibitory effect of ox-LDL on NeuN expression (P < 0.05). Treatment with ox-LDL significantly inhibited Akt phosphorylation (P < 0.05) and CREB phosphorylation induced by ATRA, EGF, and basic FGF (P < 0.05). The present study indicates that treatment with ox-LDL inhibits the differentiation of mouse NPCs into neural cells by inhibiting Akt and CREB activation.