Decreased Macrophage Infiltration Research Articles

Inhibition of FoxO1 ameliorates hepatic steatosis and hepatitis in nonalcoholic steatohepatitis mice through regulation of gut microbiota.

We aimed to investigate the role of forkhead box O1 (FoxO1) inhibitor AS1842856 (AS) in nonalcoholic steatohepatitis (NASH) mice and the potential mechanisms. Mice were given methionine-choline-sufficient (MCS), or methionine- and choline-deficient (MCD) diet for 5 weeks, along with AS (60 mg/kg) or vehicle gavage treatment (0.2 mL/day). Body and liver weight, serum triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), alanine aminotransferase (ALT), aspartate aminotransferase (AST), fasting glucose and insulin levels were measured. Liver macrophage infiltration and ileal ZO-1 protein expression were also detected. Interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α, sterol regulatory element binding protein (SREBP)-1c, phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (G6Pase), α-smooth muscle actin (SMA), recombinant collagen type III α1 (Col3a1), and connective tissue growth factor (Ctgf) expressions were measured. Stool samples were collected for 16S rDNA sequencing. Compared to the MCD group, AS attenuated liver weight, reduced serum TG, ALT, and AST levels, increased HDL-C levels, mitigated hepatic steatosis, decreased macrophage infiltration, and augmented ileal ZO-1 proteins in NASH mice. It also reduced the levels of IL-6, IL-1β, and TNF-α, alongside with the Srebp-1c mRNA expression. However, no significant effects on Pepck, G6Pase, α-SMA, Col3a1, or Ctgf were observed. Furthermore, AS promoted diversity and altered gut microbiota composition in NASH mice, causing increased beneficial bacteria like Akkermansia muciniphila, Parabacteroides distasonis, and Prevotellamassilia, which were associated with metabolic functions. FoxO1 inhibitor AS ameliorated hepatic steatosis, inflammation, and intestinal dysbiosis in NASH mice, making it a potentially promising treatment for NASH.

The analgesic effects of Yu-Xue-Bi tablet (YXB) on mice with inflammatory pain by regulating LXA4-FPR2-TRPA1 pathway

BackgroundOxylipins including lipoxin A4 (LXA4) facilitate the resolution of inflammation and possess analgesic properties by inhibiting macrophage infiltration and transient receptor potential (TRP) protein expression. Yu-Xue-Bi Tablet (YXB) is a traditional Chinese patent medicine used to relieve inflammatory pain. Our previous research has shown that the analgesic effect of YXB is related to inhibiting peripheral inflammation and regulating macrophage infiltration, but the mechanism is not yet clear. The purpose of this study is to explore the mechanisms of YXB on mice models with Complete Freund’s Adjuvant (CFA)-induced inflammatory pain from the perspective at the resolution of inflammation.MethodsMechanical allodynia thresholds and heat hypersensitivity were measured using the Von Frey test and the hot plate test respectively. The open field test and the tail suspension test were employed to measure anxiety and depressive behaviors respectively. The expression of CD68+ and the proportion of F4/80+CD11b+ cells were measured by immunofluorescence staining and flow cytometry. The expression of transient receptor potential ankyrin 1(TRPA1) was measured by immunofluorescence staining and western blotting. Oxylipins omics analysis provided quantitative data on oxylipins in the paws, and enzyme linked immunosorbent assay (ELISA) was used to measure the levels of LXA4 there. Immunofluorescence staining was used to perform the expression of Leukotriene A4 hydroxylase (LTA4H) in the paws of mice. The impact of injecting the formyl peptide receptor 2(FPR2) antagonist WRW4 and the TRPA1 agonist AITC into the left paws was observed, focusing on the expression of mechanical allodynia thresholds, the expression of CD68+, TRPA1 in the paws, and Calcitonin gene-related peptide (CGRP) in the L5 spinal dorsal horn.ResultsYXB elevated mechanical allodynia thresholds, alleviated heat hypersensitivity and anxiety and depressive behaviors in CFA mice. It significantly reduced the number of CD68+ and proportion of F4/80+CD11b+ within the paws, thereby decreasing macrophage infiltration. Additionally, it diminished the expression of TRPA1 in the paws and TRPV1 in the DRG, leading to an inhibition of peripheral sensitization. Through quantitative analysis, it was found that YXB could modulate DHA-derived oxylipins and LXA4. ELISA results indicated that YXB elevated the levels of LXA4 and inhibited the expression of LAT4H in the paws. Furthermore, the pro-resolution and analgesic effects of YXB were hindered after administration of the FPR2 antagonist. Compared with the AITC group, YXB showed no significant improvement in anti-inflammatory and analgesic effects.ConclusionsYXB can regulate the oxylipins of paws in CFA mice to promote the resolution of inflammation. The LXA4-FPR2-TRPA1 pathway is a key mechanism for the resolution of inflammation and analgesic effects.

CD146-dependent macrophage infiltration promotes epidural fibrosis via the Erdr1/ERK/CCR2 pathway

Low back pain due to epidural fibrosis is a major complication after spine surgery. Macrophages infiltrate the wound area post laminectomy, but the role of macrophages in epidural fibrosis remains largely elusive. In a mouse model of laminectomy, macrophage depletion decreased epidural fibrosis. CD146, an adhesion molecule involved in cell migration, is expressed by macrophages. CD146-defective macrophages exhibited impaired migration, which was mediated by reduced expression of CCR2 and suppression of the MAPK/ERK signaling pathway. CD146-defective macrophages suppress the MAPK/ERK signaling pathway by increasing Erdr1. In vivo, CD146 deficiency decreased macrophage infiltration and reduced extracellular matrix deposition in wound tissues. Moreover, the anti-CD146 antibody AA98 suppressed macrophage infiltration and epidural fibrosis. Taken together, these findings demonstrated that CD146 deficiency alleviates epidural fibrosis by decreasing the migration of macrophages via the Erdr1/ERK/CCR2 pathway. Blocking CD146 and macrophage infiltration may help alleviate epidural fibrosis.

Efficacy of Trametinib in Alleviating Cisplatin-Induced Acute Kidney Injury: Inhibition of Inflammation, Oxidative Stress, and Tubular Cell Death in a Mouse Model.

Cisplatin, a platinum-based chemotherapeutic, is effective against various solid tumors, but its use is often limited by its nephrotoxic effects. This study evaluated the protective effects of trametinib, an FDA-approved selective inhibitor of mitogen-activated protein kinase kinase 1/2 (MEK1/2), against cisplatin-induced acute kidney injury (AKI) in mice. The experimental design included four groups, control, trametinib, cisplatin, and a combination of cisplatin and trametinib, each consisting of eight mice. Cisplatin was administered intraperitoneally at a dose of 20 mg/kg to induce kidney injury, while trametinib was administered via oral gavage at 3 mg/kg daily for three days. Assessments were conducted 72 h after cisplatin administration. Our results demonstrate that trametinib significantly reduces the phosphorylation of MEK1/2 and extracellular signal-regulated kinase 1/2 (ERK1/2), mitigated renal dysfunction, and ameliorated histopathological abnormalities. Additionally, trametinib significantly decreased macrophage infiltration and the expression of pro-inflammatory cytokines in the kidneys. It also lowered lipid peroxidation by-products, restored the reduced glutathione/oxidized glutathione ratio, and downregulated NADPH oxidase 4. Furthermore, trametinib significantly inhibited both apoptosis and necroptosis in the kidneys. In conclusion, our data underscore the potential of trametinib as a therapeutic agent for cisplatin-induced AKI, highlighting its role in reducing inflammation, oxidative stress, and tubular cell death.

Cassia alata's dual role in modulating MUC2 expression in Eimeria papillata-infected jejunum and assessing its anti-inflammatory effects.

Coccidiosis poses significant hazards to animals, particularly in terms of compromised health, reduced productivity, and economic losses in livestock farming. The conventional treatments for coccidiosis often involve synthetic drugs, contributing to concerns about drug resistance and environmental impact. The pressing need for eco-friendly alternatives is highlighted in this study, emphasizing the importance of exploring medicinal plants like Cassia alata leaf extracts (CAE) against Eimeria papillata-induced infection in mice. The CAE exhibited significant phenolic (2.17 ± 0.03 g/100 g) and flavonoid (0.14 ± 0.01 g/100 g) content and demonstrated notable antioxidant activity. In infected mice, the CAE treatment led to a substantial reduction in oocyst output (~6 fold), ameliorating necrotic enteritis and inflammatory changes in the jejunum. Additionally, CAE treatment increased goblet cell numbers (9.3 ± 0.1 / villus) and decreased macrophage infiltration in the intestinal villi. Molecular analyses revealed CAE's positive modulation of MUC2 gene and notably reduced the levels of pro-inflammatory cytokines (specifically IL-1β, IL-10, and IFN-γ) when contrasted with the infected cohort. Furthermore, CAE treatment significantly reduced nitric oxide levels (44.03 ± 2.4 μmol/mg), showcasing its anti-inflammatory properties. The findings of this study not only contribute to the understanding of CAE's therapeutic potential but also underscore the importance of seeking eco-friendly alternatives in the face of coccidiosis challenges, addressing both the well-being of animals and the sustainability of agricultural practices. RESEARCH HIGHLIGHTS: Cassia alata extract (CAE) exhibited significant phenolic and flavonoid content, displaying notable antioxidant activity. In infected mice, CAE treatment led to a substantial reduction in oocyst output, ameliorating necrotic enteritis and inflammatory changes in the jejunum. CAE treatment increased goblet cell numbers and decreased macrophage infiltration in the intestinal villi, while molecular analyses revealed its positive modulation of the MUC2 gene and notable reduction in pro-inflammatory cytokine levels. Additionally, CAE treatment significantly reduced nitric oxide levels, showcasing its anti-inflammatory properties.

Spinal cord stimulation attenuates paclitaxel-induced gait impairment and mechanical hypersensitivity via peripheral neuroprotective mechanisms in tumor-bearing rats

BackgroundTaxanes such as paclitaxel (PTX) induce dose-dependent chemotherapy-induced peripheral neuropathy (CIPN), which is associated with debilitating chronic pain and gait impairment. Increased macrophage-related proinflammatory activities have been reported to mediate...

Decreased atherosclerosis and abdominal aortic aneurysm in mice deficient in polymeric immunoglobulin receptor

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): La Caixa Banking Foundation and Comunidad de Madrid Background Polymeric immunoglobulin receptor (PIGR) is a transmembrane protein involved in the transcytosis of polymeric immunoglobulins that is widely expressed in mucosal epithelial cells. Recent data from our group described increased PIGR levels in plasma and tissue of atherosclerotic subjects. However, the role for PIGR in the mechanisms involved in vascular remodeling has not been addressed. Purpose To analyse the role for PIGR in experimental mouse models of atherosclerosis and abdominal aortic aneurysm (AAA). Methods We analyzed PIGR expression, secretion and distribution in early atherosclerotic plaques and AAA tissues compared to healthy aortic samples, as well as in macrophages derived from the human monocytic THP-1 cell line. Next, we studied the effect of global PIGR deficiency in experimental atherosclerosis (Ldlr-/- Pigr-/- mice fed with atherogenic diet for 10 weeks). In addition, the contribution of hematopoietic PIGR was assessed in both experimental atherosclerosis and AAA (Ldlr-/- mice fed with atherogenic diet and 1 µg/Kg/min angiotensin II infusion for 28 days) by bone marrow transplantation experiments. Finally, bone marrow-derived macrophages (BMDMs) from Pigr-/- and control mice were isolated to assess their inflammatory expression profile and modulation of polarization in response to oxidized LDL (ox-LDL), as well as their ability to promote foam cell formation. Results PIGR expression was increased in the intima of early human atherosclerotic lesions and showed colocalization with CD68+ expression. PIGR expression was also increased during the in vitro differentiation of THP-1 monocytes to macrophages with phorbol myristate acetate. Both global and hematopoietic-specific PIGR deficient mice displayed reduced plaque size in the aortic sinuses as well as a strong decrease in macrophage infiltration (CD68+ cells), while no changes in smooth muscle cells (α-SMA+ cells) and collagen content were observed. Regarding AAA, increased PIGR levels were found in human AAA tissues, associated with infiltrating CD68+ cells. PIGR deficiency in hematopoietic cells also showed significantly reduced AAA dilatation and reduced macrophage infiltration. In vitro experiments with BMDMs obtained from Pigr-/- mice and stimulated with ox-LDL showed reduced proinflammatory gene expression (TNF-a and IL-6) and M1 markers (iNOS and CD11c) as well as diminished foam cell formation. Conclusions PIGR deficiency in hematopoietic cells decreases atherosclerosis and AAA progression by modulating macrophage inflammatory responses, suggesting a novel proinflammatory role for PIGR in vascular pathologies. Future experiments will test the potential therapeutic effect of modulating PIGR to dampen the inflammatory profile in vascular diseases.Results in human and mouse studies

ITGAM: A Pivotal Regulator in Macrophage Dynamics and Cardiac Function During Sepsis-Induced Cardiomyopathy.

Sepsis-induced cardiomyopathy (SIC) is a critical complication arising from sepsis characterized by reversible myocardial dysfunction. Despite the increasing attention to SIC in research, the underlying molecular mechanisms remain poorly comprehended. In this study, we utilized bioinformatics to analyze RNA-sequencing (RNA-seq) and single-cell RNA-sequencing (scRNA-seq) data from the Gene Expression Omnibus (GEO) database to identify key immune cell populations and molecular markers associated with SIC. Our experimental approach combined in vitro and in vivo studies to investigate the roles of integrin alpha M(ITGAM) and intracellular adhesion molecule-1(ICAM-1) in macrophage recruitment and phenotypic polarization, as well as their impact on cardiac function during SIC. The bioinformatics analysis disclosed significant alterations in gene expression and immune cell composition within the cardiac tissue during SIC, where macrophages emerged as the predominant immune cell type. Notably, ITGAM was identified as a key regulatory molecule that modulates macrophage function, driving the pathogenesis of SIC through its influence on the recruitment and functional reprogramming of these cells. In vitro experiments revealed that lipopolysaccharide (LPS) stimulation triggered an upregulation of ITGAM in macrophages and ICAM-1 in endothelial cells, underscoring their critical roles in immune cell mobilization and intercellular communication. The strategic administration of ITGAM-neutralizing antibodies to SIC mice resulted in a marked decrease in macrophage infiltration within the cardiac tissue, which was initially associated with an improvement in cardiac function. However, this intervention paradoxically resulted in an increased mortality rate during the later phases of SIC, underscoring the complex and dualistic function of ITGAM. This study provides new insights into the complex dynamics of immune cells within the cardiac environment during SIC, with a particular emphasis on the modulatory role of ITGAM in shaping macrophage behavior. The findings shed light on the reversible nature of myocardial dysfunction in SIC and emphasize the importance of targeted therapeutic strategies for the effective management of SIC.

Disulfiram treatment suppresses antibody-producing reactions by inhibiting macrophage activation and B cell pyrimidine metabolism

Disulfiram treatment suppresses antibody-producing reactions by inhibiting macrophage activation and B cell pyrimidine metabolism

Faecalibacterium prausnitzii Supplementation Prevents Intestinal Barrier Injury and Gut Microflora Dysbiosis Induced by Sleep Deprivation.

Sleep deprivation (SD) leads to impaired intestinal barrier function and intestinal flora disorder, especially a reduction in the abundance of the next generation of probiotic Faecalibacterium prausnitzii (F. prausnitzii). However, it remains largely unclear whether F. prausnitzii can ameliorate SD-induced intestinal barrier damage. A 72 h SD mouse model was used in this research, with or without the addition of F. prausnitzii. The findings indicated that pre-colonization with F. prausnitzii could protect against tissue damage from SD, enhance goblet cell count and MUC2 levels in the colon, boost tight-junction protein expression, decrease macrophage infiltration, suppress pro-inflammatory cytokine expression, and reduce apoptosis. We found that the presence of F. prausnitzii helped to balance the gut microbiota in SD mice by reducing harmful bacteria like Klebsiella and Staphylococcus, while increasing beneficial bacteria such as Akkermansia. Ion chromatography analysis revealed that F. prausnitzii pretreatment increased the fecal butyrate level in SD mice. Overall, these results suggested that incorporating F. prausnitzii could help reduce gut damage caused by SD, potentially by enhancing the intestinal barrier and balancing gut microflora. This provides a foundation for utilizing probiotics to protect against intestinal illnesses.

The novel vaccines targeting interleukin-1 receptor type I

ObjectiveThere is mounting evidence indicating that atherosclerosis represents a persistent inflammatory process, characterized by the presence of inflammation at various stages of the disease. Interleukin-1 (IL-1) precisely triggers inflammatory signaling pathways by binding to interleukin-1 receptor type I (IL-1R1). Inhibition of this signaling pathway contributes to the prevention of atherosclerosis and myocardial infarction. The objective of this research is to develop therapeutic vaccines targeting IL-1R1 as a preventive measure against atherosclerosis and myocardial infarction. MethodsILRQβ-007 and ILRQβ-008 vaccines were screened, prepared and then used to immunize high-fat-diet fed ApoE-/- mice and C57BL/6J mice following myocardial infarction. Progression of atherosclerosis in ApoE-/- mice was assessed primarily by oil-red staining of the entire aorta and aortic root, as well as by detecting the extent of macrophage infiltration. The post-infarction cardiac function in C57BL/6J mice were evaluated using cardiac ultrasound and histological staining. ResultsILRQβ-007 and ILRQβ-008 vaccines stimulated animals to produce high titers of antibodies that effectively inhibited the binding of interleukin-1β and interleukin-1α to IL-1R1. Both vaccines effectively reduced atherosclerotic plaque area, promoted plaque stabilization, decreased macrophage infiltration in plaques and influenced macrophage polarization, as well as decreasing levels of inflammatory factors in the aorta, serum, and ependymal fat in ApoE-/- mice. Furthermore, these vaccines dramatically improved cardiac function and macrophage infiltration in C57BL/6J mice following myocardial infarction. Notably, no significant immune-mediated damage was observed in immunized animals. ConclusionThe vaccines targeting the IL-1R1 would be a novel and promising treatment for the atherosclerosis and myocardial infarction.

Abstract 5537: How aging promotes immune mediated reactivation from metastatic melanoma dormancy

Abstract Disseminated cancer cells that escape the primary tumor can seed distal tissues but may take several years to grow into clinically detectable metastases, a phenomenon termed tumor dormancy. Despite its importance in metastasis and residual disease, few studies have been able to successfully model melanoma dormancy. We have previously shown that while tumors grow more slowly in aged mouse skin, they form more lung metastases in aged mice compared to young mice. We queried whether the lung microenvironment undergoes age-related changes that establish a permissive niche for metastatic outgrowth. We identified that Wnt5A and AXL are not only required for efficient dissemination away from the primary tumor but also activate dormancy of melanoma cells within the lung. The young lung microenvironment maintains melanoma cells in a dormant state; however, age-associated reprograming of lung fibroblasts increases secretion of the soluble Wnt antagonist sFRP1, which inhibits both Wnt5A and AXL to enable reactivation from dormancy and the formation of larger metastatic colonies in the aged lung. We found that downregulation of AXL in melanoma cells leads to an increase in the related TAM family receptor MERTK, which promotes a proliferative melanoma phenotype and enables reactivation from dormancy. We have now found that both the aged-pre and post metastatic niche regulate immune cells in the lung to create a permissive niche for reactivation of metastatic melanoma. NK cells are significantly decreased in the healthy lungs of aged mice, are significantly less active, and have increased exhaustion markers. NK cell infiltration remains low in early and late-stage metastasis in aged mice. Depletion of NK cells in young mice is sufficient to induce reactivation from dormancy. Further, MERTK induced reactivation of melanoma cells results in paracrine secretion of its own ligand PROS1 to facilitate a growth permissive lung microenvironment. Melanoma-secreted PROS1 increases infiltration of PMN-MDSCs and decreases macrophage infiltration to maintain an immunosuppressive lung niche for efficient outgrowth. Selective inhibition of PMN-MDSCs using a TRIAL-R2 agonistic antibody significantly decreases metastatic outgrowth and promotes smaller, non-proliferative dormant colonies. Our findings indicate a significant role that aging plays in altering NK-cell infiltration and function to create a growth permissive pre-metastatic niche and how reactivation from dormancy can further contribute to create an immunosuppressive microenvironment for efficient outgrowth via PROS1 induced infiltration of PMN-MDSCs. Importantly, the clear differences found in our young and aged mouse modelling systems for outgrowth in metastatic tissues necessitates the need for age-appropriate pre-clinical modelling for better patient and disease representation. Citation Format: Pulkit Datt, Jhon Passamonte, Christopher Price, Daniel Zabransky, Yash Chhabra, Ashani Weeraratna, Mitchell E. Fane. How aging promotes immune mediated reactivation from metastatic melanoma dormancy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5537.

Decoding the regulatory role of ATP synthase inhibitory factor 1 (ATPIF1) in Wallerian degeneration and peripheral nerve regeneration

AbstractATP synthase inhibitory factor 1 (ATPIF1), a key modulator of ATP synthase complex activity, has been implicated in various physiological and pathological processes. While its role is established in conditions such as hypoxia, ischemia‐reperfusion injury, apoptosis, and cancer, its involvement remains elusive in peripheral nerve regeneration. Leveraging ATPIF1 knockout transgenic mice, this study reveals that the absence of ATPIF1 impedes neural structural reconstruction, leading to delayed sensory and functional recovery. RNA‐sequencing unveils a significant attenuation in immune responses following peripheral nerve injury, which attributes to the CCR2/CCL2 signaling axis and results in decreased macrophage infiltration and activation. Importantly, macrophages, not Schwann cells, are identified as key contributors to the delayed Wallerian degeneration in ATPIF1 knockout mice, and affect the overall outcome of peripheral nerve regeneration. These results shed light on the translational potential of ATPIF1 for improving peripheral nerve regeneration.

Egg white hydrolysate protects white adipose tissue against metabolic insult in deoxycorticosterone acetate-salt rats.

The purpose of this study was to investigate the effect of an egg white hydrolysate (EWH) to protect white adipose tissue damage from cardiometabolic changes induced by severe hypertension. Male Wistar rats were uninephrectomised and divided: SHAM (weekly subcutaneous vehicle (mineral oil + propylene glycol, 1:1)), SHAM + EWH (subcutaneous vehicle plus EWH via gavage, 1 g/kg per day), DOCA (deoxycorticosterone acetate diluted in vehicle subcutaneously weekly in subsequent doses of 20 mg/kg -1st week, 12 mg/kg - 2–3th week, and 6 mg/kg -4–8th week, respectively, plus 1 % NaCl and 0·2 % KCl in drinking water), and DOCA + EWH. Body weight gain, food and water intake, glucose and lipid metabolism were evaluated. Oxidative stress was assessed by biochemical assay and immunofluorescence for NOX-1, nuclear factor kappa B (NFκB), and caspase-3 in retroperitoneal white adipose tissue (rtWAT). Proinflammatory cytokines (IL-6 and 1β), CD163+ macrophage infiltration, and immunohistochemistry for TNFα and uncoupling protein-1 were evaluated, as well as histological analysis on rtWAT. Glutathione peroxidase and reductase were also determined in plasma. EWH showed hypocholesterolemic, antioxidant, anti-inflammatory, and anti-apoptotic properties in the arterial hypertension DOCA-salt model. The results demonstrated the presence of functional changes in adipose tissue function by a decrease in macrophage infiltration and in the fluorescence intensity of NFκB, NOX-1, and caspase-3. A reduction of proinflammatory cytokines and restoration of antioxidant enzymatic activity and mitochondrial oxidative damage by reducing uncoupling protein-1 fluorescence intensity were also observed. EWH could be used as a potential alternative therapeutic strategy in the treatment of cardiometabolic complications associated with malignant secondary arterial hypertension.

Antisense oligonucleotide targeting hepatic Serum Amyloid A limits the progression of angiotensin II-induced abdominal aortic aneurysm formation

Background and aimsObesity increases the risk for abdominal aortic aneurysms (AAA) in humans and enhances angiotensin II (AngII)-induced AAA formation in C57BL/6 mice. We reported that deficiency of Serum Amyloid A (SAA) significantly reduces AngII-induced inflammation and AAA in both hyperlipidemic apoE-deficient and obese C57BL/6 mice. The aim of this study is to investigate whether SAA plays a role in the progression of early AAA in obese C57BL/6 mice. MethodsMale C57BL/6J mice were fed a high-fat diet (60% kcal as fat) throughout the study. After 4 months of diet, the mice were infused with AngII until the end of the study. Mice with at least a 25% increase in the luminal diameter of the abdominal aorta after 4 weeks of AngII infusion were stratified into 2 groups. The first group received a control antisense oligonucleotide (Ctr ASO), and the second group received ASO that suppresses SAA (SAA-ASO) until the end of the study. ResultsPlasma SAA levels were significantly reduced by the SAA ASO treatment. While mice that received the control ASO had continued aortic dilation throughout the AngII infusion periods, the mice that received SAA-ASO had a significant reduction in the progression of aortic dilation, which was associated with significant reductions in matrix metalloprotease activities, decreased macrophage infiltration and decreased elastin breaks in the abdominal aortas. ConclusionsWe demonstrate for the first time that suppression of SAA protects obese C57BL/6 mice from the progression of AngII-induced AAA. Suppression of SAA may be a therapeutic approach to limit AAA progression.

Inflammation Is More Sensitive than Cell Proliferation in Response to Rapamycin Treatment in Polycystic Kidney Disease

Introduction: It has been reported that rapamycin inhibited inflammation in renal interstitial diseases. We therefore hypothesized that rapamycin could attenuate inflammation in polycystic kidney disease (PKD). Methods: Han:SPRD rats were treated with rapamycin by daily gavage from 4 weeks to 12 weeks of age at the dosage of 0.5 mg/kg/day (low dose) or 1 mg/kg/day (high dose). WT9-12 human PKD cells were treated with various concentrations of rapamycin. Results: Two-kidney/total body weight ratio and cystic index in Cy/+ kidneys were significantly reduced with the treatment of low-dose rapamycin and further reduced by the treatment with high-dose rapamycin. However, the renal function of Cy/+ rats was equally improved by the treatment with either low-dose or high-dose rapamycin. The renal cell proliferation was significantly decreased in Cy/+ kidneys with the treatment of low-dose rapamycin and was further decreased with the treatment of high-dose rapamycin as examined by Ki67 staining. The phosphorylation of S6K in cystic kidneys was decreased by low-dose rapamycin and further decreased by high-dose rapamycin. Both low-dose and high-dose rapamycin treatment decreased macrophage infiltration and the expression of complement factor B (CFB), monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor-alpha (TNF-α) to a similar level. The expression of CFB, MCP-1, and TNF-α and phosphorylation of S6K were inhibited in WT9-12 cells treated with 10 nm rapamycin at 24 h and 48 h, respectively. Moreover, the phosphorylation of Akt was not increased by 1 nm and 10 nm of rapamycin and enhanced by 1 μm rapamycin treatment. Interestingly, WT9-12 cell proliferation could be inhibited by 1 μm rapamycin. Conclusion: Low dose of rapamycin could inhibit inflammation and protect renal function in PKD. Inflammation is more sensitive than cell proliferation in response to rapamycin treatment in PKD.

Krameria lappacea root extract's anticoccidial properties and coordinated control of CD4 T cells for IL-10 production and antioxidant monitoring.

Recently, the use of botanicals as an alternative to coccidiostats has been an appealing approach for controlling coccidiosis. Therefore, this study was conducted to evaluate the potential role of aqueous methanolic extract (200 mg/kg) of Krameria lappacea (roots) (KLRE) against infection induced by Eimeria papillata. A total of 25 male C57BL/6 mice were divided into five groups (I, II, III, IV, and V). On 1st day of the experiment, all groups except groups I (control) and II (non-infected-treated group with KLRE), were inoculated orally with 103 sporulated E. papillata oocysts. On the day of infection, group IV was treated with KLRE. Group V served as an infected-treated group and was treated with amprolium (coccidiostat). Treatment with extract and coccidiostat was continued for five consecutive days. While not reaching the efficacy level of the reference drug (amprolium), KLRE exhibited notable anticoccidial activity as assessed by key criteria, including oocyst suppression rate, total parasitic stages, and maintenance of nutrient homeostasis. The presence of phenolic and flavonoid compounds in KLRE is thought to be responsible for its positive effects. The Eimeria infection increased the oxidative damage in the jejunum. KLRE treatment significantly increased the activity of catalase and superoxide dismutase. On the contrary, KLRE decreased the level of malondialdehyde and nitric oxide. Moreover, KLRE treatment decreased macrophage infiltration in the mice jejunal tissue, as well as the extent of CD4 T cells and NFkB. E. papillata caused a state of systemic inflammatory response as revealed by the upregulation of inducible nitric oxide synthase (iNOs)-mRNA. Upon treatment with KLRE, the activity of iNOs was reduced from 3.63 to 1.46 fold. Moreover, KLRE was able to downregulate the expression of pro-inflammatory cytokines interferon-γ, nuclear factor kappa B, and interleukin-10 -mRNA by 1.63, 1.64, and 1.38 fold, respectively. Moreover, KLRE showed a significant reduction in the expression of IL-10 protein level from 104.27 ± 8.41 pg/ml to 62.18 ± 3.63 pg/ml. Collectively, K. lappacea is a promising herbal medicine that could ameliorate the oxidative stress and inflammation of jejunum, induced by E. papillata infection in mice.

C-X-C domain ligand 14-mediated stromal cell–macrophage interaction as a therapeutic target for hand dermal fibrosis

Dupuytren’s contracture, a superficial dermal fibrosis, causes flexion contracture of the affected finger, impairing hand function. Specific single-nucleotide polymorphisms within genes in the Wnt signalling pathway are associated with the disease. However, the precise role of Wnt signalling dysregulation in the onset and progression of Dupuytren’s contracture remains unclear. Here, using a fibrosis mouse model and clinical samples of human Dupuytren’s contractures, we demonstrate that the activation of Wnt/β-catenin signalling in Tppp3-positive cells in the dermis of the paw is associated with the development of fibrosis. Fibrosis development and progression via Wnt/β-catenin signalling are closely related to stromal cell–macrophage interactions, and Wnt/β-catenin signalling activation in Tppp3-positive stromal cells causes M2 macrophage infiltration via chemokine Cxcl14, resulting in the formation of a TGF-β-expressing fibrotic niche. Inhibition of Cxcl14 mitigates fibrosis by decreasing macrophage infiltration. These findings suggest that Cxcl14-mediated stromal cell–macrophage interaction is a promising therapeutic target for Wnt/β-catenin-induced fibrosis.

Myeloid PFKFB3-mediated glycolysis promotes kidney fibrosis.

Excessive renal fibrosis is a common pathology in progressive chronic kidney diseases. Inflammatory injury and aberrant repair processes contribute to the development of kidney fibrosis. Myeloid cells, particularly monocytes/macrophages, play a crucial role in kidney fibrosis by releasing their proinflammatory cytokines and extracellular matrix components such as collagen and fibronectin into the microenvironment of the injured kidney. Numerous signaling pathways have been identified in relation to these activities. However, the involvement of metabolic pathways in myeloid cell functions during the development of renal fibrosis remains understudied. In our study, we initially reanalyzed single-cell RNA sequencing data of renal myeloid cells from Dr. Denby's group and observed an increased gene expression in glycolytic pathway in myeloid cells that are critical for renal inflammation and fibrosis. To investigate the role of myeloid glycolysis in renal fibrosis, we utilized a model of unilateral ureteral obstruction in mice deficient of Pfkfb3, an activator of glycolysis, in myeloid cells (Pfkfb3 ΔMϕ ) and their wild type littermates (Pfkfb3 WT). We observed a significant reduction in fibrosis in the obstructive kidneys of Pfkfb3 ΔMϕ mice compared to Pfkfb3 WT mice. This was accompanied by a substantial decrease in macrophage infiltration, as well as a decrease of M1 and M2 macrophages and a suppression of macrophage to obtain myofibroblast phenotype in the obstructive kidneys of Pfkfb3 ΔMϕ mice. Mechanistic studies indicate that glycolytic metabolites stabilize HIF1α, leading to alterations in macrophage phenotype that contribute to renal fibrosis. In conclusion, our study implicates that targeting myeloid glycolysis represents a novel approach to inhibit renal fibrosis.

Notch Signaling Regulates Immunosuppressive Tumor-Associated Macrophage Function in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDA) continues to have a dismal prognosis. The poor survival of patients with PDA has been attributed to a high rate of early metastasis and low efficacy of current therapies, which partly result from its complex immunosuppressive tumor microenvironment. Previous studies from our group and others have shown that tumor-associated macrophages (TAM) are instrumental in maintaining immunosuppression in PDA. Here, we explored the role of Notch signaling, a key regulator of immune response, within the PDA microenvironment. We identified Notch pathway components in multiple immune cell types within human and mouse pancreatic cancer. TAMs, the most abundant immune cell population in the tumor microenvironment, expressed high levels of Notch receptors, with cognate ligands such as JAG1 expressed on tumor epithelial cells, endothelial cells, and fibroblasts. TAMs with activated Notch signaling expressed higher levels of immunosuppressive mediators, suggesting that Notch signaling plays a role in macrophage polarization within the PDA microenvironment. Genetic inhibition of Notch in myeloid cells led to reduced tumor size and decreased macrophage infiltration in an orthotopic PDA model. Combination of pharmacologic Notch inhibition with PD-1 blockade resulted in increased cytotoxic T-cell infiltration, tumor cell apoptosis, and smaller tumor size. Our work implicates macrophage Notch signaling in the establishment of immunosuppression and indicates that targeting the Notch pathway may improve the efficacy of immune-based therapies in patients with PDA.