Monocyte Chemoattractant Protein-1 Expression Research Articles

Abstract TP375: Ischemic Insult Under Hyperhomocysteinemic Condition Triggers Early Onset Of Inflammatory Response Causing Exacerbation Of Brain Injury

Hyperhomocysteinemia, a metabolic disorder characterized by systemic elevation of amino acid homocysteine, is linked to deficiency in vitamins and enzymes involved in homocysteine metabolism. The incidence of hyperhomocysteinemia is high in the elderly population due to reduced micronutrient absorption and metabolism. Recent preclinical studies in animal models of stroke showed that predisposition to hyperhomocysteinemia exacerbates ischemic brain injury and worsens behavioral deficits, establishing hyperhomocysteinemia as a potential comorbidity for stroke. These studies further showed that hyperhomocysteinemia-induced stimulation of GluN2A subunit containing NMDA receptors (GluN2A-NMDARs) in conjunction with glutamate-induced stimulation of GluN2B subunit containing NMDARs (GluN2B-NMDARs) exacerbates stroke pathology. However, the precise intracellular mechanisms involved in such exacerbation of ischemic brain injury is not known. The current study sought to investigate whether under hyperhomocysteinemic condition GluN2A-NMDAR mediated early activation of the transcription factor Nuclear Factor-κB (NFκB) and subsequent expression of the pro-inflammatory chemokine Monocyte chemoattractant protein-1 (MCP-1) enhances post-ischemic inflammatory response and exacerbation of brain damage. Adult male Wistar rats were made hyperhomocysteinemic by implantation of Alzet osmotic pumps containing L-homocysteine. The animals were hyperhomocysteinemic within 3 days with a total plasma homocysteine level of ~24 μM. Acute ischemic stroke was induced by middle cerebral artery occlusion for 60 min followed by reperfusion (6h). Brain tissues were processed for MCP-1 ELISA and RT-PCR. A significant increase in MCP-1 mRNA and protein levels were observed in the ipsilateral cortex of hyperhomocysteinemic rats compared to control rats within 6h of reperfusion. An accelerated brain damage was also observed at this time in the hyperhomocysteinemic rats. Inhibition of GluN2A-NMDAR (NVP-AAM077, i.v.) and NFκB (BMS345541, IKK inhibitor; i.p) at the onset of ischemic insult attenuated increase in MCP-1 mRNA and protein levels, as well as exacerbation of brain injury under hyperhomocysteinemic condition. The study provides compelling evidence for a novel role of GluN2A-NMDAR in promoting neuro-inflammatory response that contributes to exacerbation of stroke pathology under hyperhomocysteinemic condition.

Pericytes mediate neuroinflammation via Fli-1 in endotoxemia and sepsis in mice

BackgroundSepsis-associated encephalopathy (SAE) often results from neuroinflammation. Recent studies have shown that brain platelet-derived growth factor receptor β (PDGFRβ) cells, including pericytes, may act as early sensors of infection by secreting monocyte chemoattractant protein-1 (MCP-1), which transmits inflammatory signals to the central nervous system. The erythroblast transformation-specific (ETS) transcription factor Friend leukemia virus integration 1 (Fli-1) plays a critical role in inflammation by regulating the expression of key cytokines, including MCP-1. However, the role of pericyte Fli-1 in neuroinflammation during sepsis remains largely unknown.MethodsWT and pericyte-specific Fli-1 knockout mice were subjected to endotoxemia through LPS injection or sepsis via cecal ligation and puncture (CLP). In vitro, Fli-1 was knocked down using small interfering RNA in cultured mouse brain pericytes, followed by LPS stimulation.ResultsElevated Fli-1 levels were observed in isolated brain pericytes 2 h after LPS administration, in brain tissues 4 h after CLP, and in cultured mouse brain pericytes 2 h after LPS stimulation in vitro. In endotoxemic mice, pericyte-specific Fli-1 knockout reduced expression of MCP-1 and IL-6 in brain tissue 2 h after LPS injection. At 24 h post-LPS administration, protein levels of MCP-1 and IL-6, and microglia activation were suppressed in pericyte-Fli-1 knockout mice. Additionally, Fli-1 deficiency in pericytes significantly reduced MCP-1 and IL-6 mRNA levels in the brain tissue 4 h after CLP. Moreover, in cultured brain pericytes, Fli-1 knockdown markedly decreased MCP-1 and IL-6 levels after LPS stimulation. Notably, LPS stimulation increased Fli-1 levels via TLR4-Myd88 signaling, which subsequently led to elevated production of MCP-1 in brain pericytes.ConclusionsFli-1 in pericytes may serve as a crucial mediator of neuroinflammation during sepsis by directly regulating pivotal cytokines such as MCP-1 and IL-6. Therefore, Fli-1 has the potential to serve as a therapeutic target in SAE and other neuroinflammatory disorders.

Association of The MCP-1 rs1024611 Polymorphism with Polycystic Ovary Syndrome in A Population of Indian Women: A Case-Control Study.

Polycystic ovary syndrome (PCOS) is one of the most prevalent endocrine conditions that significantly impact the life quality of reproductive-aged women. In the Indian population, its prevalence varies from 3.7 to 22.5% depending on ethnicity and diagnostic criteria. Chronic inflammation plays a pivotal role in PCOS pathogenesis. The monocyte chemoattractant protein-1 (MCP-1) is an important chemotactic factor for inflammatory response of monocytes. Genetic variations in the MCP-1) gene may modulate MCP-1 expression. Although the association of the MCP-1 promoter polymorphism (-2518A/G) was extensively studied in different inflammatory conditions, there is only one report in PCOS conditions. Since no study was reported from the Indian population, we aimed to explore the association of the MCP-1 -2518A/G polymorphism (rs1024611) with PCOS. In this case-control study, to analyse the distribution and association of rs1024611 with PCOS, polymerase chain reaction-fragment length polymorphism (PCR-RFLP) analysis was carried out in 202 patients who exhibited PCOS from menarche onwards or with higher severity of symptoms and 122 age-matched controls. In our study, no significant correlation was observed in rs1024611 polymorphism with PCOS patients in comparison with control. In addition to this, we found no significant difference in the genotype and allele frequencies between obese and non-obese PCOS patients. Our finding suggests that the MCP-1 -2518 A/G polymorphism has not been associated with PCOS predisposition.

Understanding the Relationship between MCP-1 SNP (rs1024611) and VEGF SNP (rs699947) with Aging and Lifestyle Habits via Computational Insights

Background: Aging is a complex biological process and is characterized by a gradual decline in physiological functions and increased vulnerability to various diseases. It is linked with the genes known as Monocyte Chemoattractant Protein-1 (MCP-1) and Vascular Endothelial Growth Factor (VEGF). MCP-1 is a key protein in generating immune response and VEGF is involved in angiogenesis. Objectives: This is a cross-sectional experimental study that aims to observe interplay between MCP-1 SNP (rs1024611) and VEGF SNP (rs699947) with aging and lifestyle habits. It delves into the biological pathways implicated in aging, as well as the impact of lifestyle elements such as dietary habits, tobacco use and physical activity on MCP-1 and VEGF expression levels. Method: The study involved the selection of 60 samples from elderly individuals and 60 samples from healthy individuals as control. The selection process was done by filling the proforma having questions related to the lifestyle habits and the use of medication since they can interfere with gene functioning. After that DNA extraction, and the identification of gene presence through PCR analysis. The assessment of PCR outcomes revealed a prevalence of the CC allele in both the experimental and control cohorts for both MCP-1 and VEGF, highlighting the critical role of these genes in the aging process. Furthermore, it posits that variations in the VEGF gene may hold significant sway over aging. Bioinformatics techniques were used to explore the relationship between MCP-1 and VEGF, employing Cytoscape STRING, KEGG pathway analysis and GO enrichment to analyze the interactions between these two genes. Results: It was observed that these genes are interconnected, functioning under the influence of the Tp65 transcriptional factor. The research findings also put forth the notion that dietary habits and physical exercise could potentially modulate the expression of these genes, thereby influencing the process of healthy aging. Those who adopted healthy lifestyle showed CC and TT genotypes for MCP-1 and VEGF respectively therefore, showing slow and healthy aging. Conclusions: The conclusion of this article suggests that the MCP-1 and VEGF genes play a crucial role in immune response, inflammation and aging. The study highlights the potential interaction between these genes in monocyte recruitment and angiogenesis.

Retinol-loaded deep eutectic solvent emulsion: Improved stability and therapeutic efficiency

Retinol is used to manage epidermal and keratin metabolism, promote collagen formation, erase wrinkles for firmer skin, and restore suppleness and smoothness. Retinol can be difficult to store and use owing to the potential for skin irritation, oxidation, and biological ineffectiveness. The linolenic acid and phosphatidylcholine deep eutectic solvent (DES) had a low melting point, high bioactivity, and integrated capsule technology for retinol encapsulation. Safety evaluation tests revealed that the formulated DES-retinol emulsion was less cytotoxic than free retinol, as well as less irritant toward chicken embryos, pig skin, and human patches. In a keratinocyte inflammatory factor inhibition assay, the DES-retinol emulsion reduced monocyte chemoattractant protein-1 expression, indicating the potential to reduce the inflammatory response of the skin to retinol-induced irritation. The DES-retinol emulsion exhibited pro-permeability, anti-wrinkle, firming, and antioxidant characteristics in cellular, skin, and clinical investigations. The DES-retinol emulsion promoted type I collagen production, suppressed matrix metalloproteinase-1 activity, and reduced the release of reactive oxygen species. Consequently, the quantity, size, and depth of wrinkles were substantially improved, along with an enhanced anti-aging effect, heightened skin hydration, increased collagen intensity and flexibility, and diminished retinol-induced irritation. In conclusion, the retinol-loaded linolenic acid and phosphatidylcholine DES emulsion exhibited improved stability, enhanced transdermal efficiency, and notable therapeutic effects.

Dynamic control of mTORC1 facilitates bone healing in mice

Bone healing requires well-orchestrated sequential actions of osteoblasts and osteoclasts. Previous studies have demonstrated that the mechanistic target of rapamycin complex 1 (mTORC1) plays a critical role in the metabolism of osteoblasts and osteoclasts. However, the role of mTORC1 in bone healing remains unclear. Here, we showed that a dynamic change in mTORC1 activity during the process was essential for proper healing and can be harnessed therapeutically for treatment of bone fractures. Low mTORC1 activity induced by osteoblastic Raptor knockout or rapamycin treatment promoted osteoblast-mediated osteogenesis, thus leading to better bone formation and shorter bone union time. Rapamycin treatment in vitro also revealed that low mTORC1 activity enhanced osteoblast differentiation and maturation. However, rapamycin treatment affected the recruitment of osteoclasts to new bone sites, thus resulting in delayed callus absorption in bone marrow cavity. Mechanistically, decreased mTORC1 activity inhibited the recruitment of osteoclast progenitor cells to healing sites through a decrease in osteoblastic expression of monocyte chemoattractant protein-1, thus inhibiting osteoclast-mediated remodeling. Therefore, normal mTORC1 activity was necessary for bone remodeling stage. Furthermore, through the use of sustained-release materials at the bone defect, we confirmed that localized application of rapamycin in early stages accelerated bone healing without affecting bone remodeling. Together, these findings revealed that the activity of mTORC1 continually changed during bone healing, and staged rapamycin treatment could be used to promote bone healing.

Dietary Protein in a Challenge Meal Does Not Alleviate Postprandial Impairments in Vascular Endothelial Function in Healthy Older Adults with Cardiometabolic Risk: A Randomized Crossover-Controlled Trial

BackgroundPostprandial vascular endothelial dysfunction is an early marker of atherosclerosis. Meal protein has been reported to reduce endothelial dysfunction in adults, and the effect could be mediated by the amino acid content. ObjectivesThis trial aims to assess the effect of a specifically designed plant-protein blend that contains high leucine, arginine, and cysteine on postprandial endothelial function in the elderly. MethodsIn a randomized, double-blind, 3-period crossover (2-wk washout), controlled trial, we compared the vascular effects of 3 high-saturated-fat high-sucrose (HFHS) meals containing either our specific plant-protein blend, or milk protein, or without added protein. The trial was conducted on 29 healthy adults aged >65 y presenting ≥2 cardiometabolic risk factors. Postprandial vascular function was evaluated at fasting, 3 h, and 5 h postprandially, using brachial flow-mediated dilation (FMD), hand microvascular reactivity (using Flowmetry Laser Doppler, FLD), and finger reactive hyperemia index (using Peripheral Arterial Tonometry, RHI). Immune cell count and gene expression in peripheral blood mononuclear cells (PBMCs) were also assessed postprandially. Data were analyzed using mixed linear models with repeated measurements on participants for meal composition and time of sampling. This trial was registered at clinicaltrials.gov as NCT04923555. ResultsFMD incremental AUC value decreased after meals (time effect P < 0.01), with no significant differences between meals. RHI also decreased with time (P < 0.01). PBMC count and monocyte chemoattractant protein-1 (MCP1), IL-1β, and IL-6 expression increased after meals showing postprandial endothelial activation (P < 0.05). Overall, meal composition had no effect on any of the postprandial changes (Ps>0.10). ConclusionsIn healthy adults aged >65 y presenting cardiometabolic risk, adding protein to an HFHS challenge meal does not mitigate postprandial impairments in vascular endothelial function and inflammatory activation. Further studies are needed to explore the potential differences with younger adults.

1α,25-Dihydroxyvitamin D Downregulates Adipocyte Impact on Breast Cancer Cell Migration and Adipokine Release.

Excess adiposity is associated with a higher risk of breast cancer metastasis and mortality. Evidence suggests that dietary vitamin D inhibits breast cancer metastasis. However, the mechanistic link between vitamin D's regulation of adipocyte metabolism and metastasis has not been previously investigated. Therefore, the purpose of these experiments was to examine the effect of the active form of vitamin D, 1α,25-dihydroxyvitamin D (1,25(OH)2D), on adipocyte release of bioactive compounds and whether the impact on adipocytes leads to inhibition of breast cancer cell migration, an important step of metastasis. Differentiated 3T3-L1 adipocytes were treated with 1,25(OH)2D for two days, followed by either harvesting the adipocytes or collecting adipocyte-conditioned media without 1,25(OH)2D. A transwell migration assay was conducted with vehicle- or 1,25(OH)2D-conditioned media. In order to explore the mechanism underlying effects on breast cancer metastatic capability, the mRNA expression of leptin, adiponectin, insulin-like growth factor (IGF-1), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) was measured in adipocytes following either vehicle or 1,25(OH)2D treatment. Conditioned media from 1,25(OH)2D-treated adipocytes inhibited the migration of metastatic MDA-MB-231 breast cancer cells compared to conditioned media from vehicle-treated adipocytes. Treatment of adipocytes with 1,25(OH)2D decreased mRNA expression of leptin, adiponectin, IGF-1, IL-6, and MCP-1. Consistent with mRNA expression, concentrations of leptin, adiponectin, IGF-1, and IL-6 in adipocyte-conditioned media were decreased with 1,25(OH)2D treatment, although MCP-1 remained unchanged. In summary, these results suggest that 1,25(OH)2D alters adipocyte secretions to prevent breast cancer metastasis.

The protective effects of apelin-13 in HIV-1 tat- induced macrophage infiltration and BBB impairment

ABSTRACT Impairment of the blood – brain barrier (BBB) and subsequent inflammatory responses contribute to the development of human immunodeficiency virus (HIV)-1-associated neurocognitive disorders (HAND). Apelin-13, the most abundant member of the apelin family, acts as the ligand of the angiotensin receptor-like 1 (APJ). However, its pharmacological function in HAND and its underlying mechanism are unknown. In the current study, we report that the presence of HIV-1 Tat reduced the levels of Apelin-13 and APJ in the cortex tissue of mice. Importantly, Apelin-13 preserved BBB integrity against HIV-1 Tat in mice by increasing the expression of the tight junction protein zonula occludens-1 (ZO-1) and occludin. Interestingly, increased macrophage infiltration, indicated by elevated CD68-positive staining was observed in the cortex after stimulation with HIV-1, which was mitigated by the administration of Apelin-13. Correspondingly, Apelin-13 reduced the expression of monocyte chemoattractant protein-1; (MCP-1). An in vitro two-chamber and two-cell trans-well assay demonstrated that HIV-1 Tat challenge significantly promoted macrophage migration, which was notably attenuated by the introduction of Apelin-13. Accordingly, treatment with Apelin-13 restored the HIV-1 Tat-induced reduction of occludin and ZO-1, while preventing the upregulation of MCP-1 in human brain microvascular endothelial cells (HBMVECs). Our results suggest that Apelin-13 may reduce macrophage infiltration into brain tissues and mitigate BBB dysfunction in patients with HAND.

Biophysically stressed vascular smooth muscle cells express MCP-1 via a PDGFR-β-HMGB1 signaling pathway.

Vascular smooth muscle cells (VSMCs) under biophysical stress play an active role in the progression of vascular inflammation, but the precise mechanisms are unclear. This study examined the cellular expression of monocyte chemoattractant protein 1 (MCP-1) and its related mechanisms using cultured rat aortic VSMCs stimulated with mechanical stretch (MS, equibiaxial cyclic stretch, 60 cycles/ min). When the cells were stimulated with 10% MS, MCP-1 expression was markedly increased compared to those in the cells stimulated with low MS intensity (3% or 5%). An enzyme-linked immunosorbent assay revealed an increase in HMGB1 released into culture media from the cells stimulated with 10% MS compared to those stimulated with 3% MS. A pretreatment with glycyrrhizin, a HMGB1 inhibitor, resulted in the marked attenuation of MCP-1 expression in the cells stimulated with 10% MS, suggesting a key role of HMGB1 on MCP-1 expression. Western blot analysis revealed higher PDGFR-α and PDGFR-β expression in the cells stimulated with 10% MS than 3% MS-stimulated cells. In the cells deficient of PDGFR-β using siRNA, but not PDGFR-α, HMGB1 released into culture media was significantly attenuated in the 10% MS-stimulated cells. Similarly, MCP-1 expression induced in 10% MS-stimulated cells was also attenuated in cells deficient of PDGFR-β. Overall, the PDGFR-β signaling plays a pivotal role in the increased expression of MCP-1 in VSMCs stressed with 10% MS. Therefore, targeting PDGFR-β signaling in VSMCs might be a promising therapeutic strategy for vascular complications in the vasculatures under excessive biophysical stress.

The Complement System Is Essential for Arteriogenesis by Enhancing Sterile Inflammation as a Relevant Step in Collateral Artery Growth.

Arteriogenesis is an inflammatory driven mechanism, describing the growth of a natural bypass from pre-existing collateral arteries to compensate for an occluded artery. The complement system component C3 is a potent natural inflammatory activator. Here, we investigated its impact on the process of collateral artery growth using C3-deficient (C3 -/-) and wildtype control mice in a murine hindlimb model of arteriogenesis. Induction of arteriogenesis by unilateral femoral artery ligation resulted in decreased perfusion recovery in C3 -/- mice on day 7 as shown by Laser Doppler imaging. Immunofluorescence staining revealed a reduced vascular cell proliferation in C3 -/- mice. Gene expression analysis displayed a significant reduction in monocyte chemoattractant protein-1 (MCP-1) expression in C3 -/- mice. Interestingly, 3 days after induction of arteriogenesis, the number of macrophages (CD68+) recruited to growing collaterals was not affected by C3 deficiency. However, a significant reduction in inflammatory M1-like polarized macrophages (CD68+/MRC1-) was noted. Forced mast cell activation by Compound 48/80 as well as exogenous MCP-1 application rescued the number of M1-like polarized macrophages along with perfusion recovery in C3 -/- mice. In summary, this study demonstrates that complement C3 influences arteriogenesis by mediating MCP-1 expression, which is essential for the induction and enhancement of sterile inflammation.

Inhibiting the JNK Signaling Pathway Attenuates Hypersensitivity and Anxiety-Like Behavior in a Rat Model of Non-specific Chronic Low Back Pain.

Low back pain (LBP) has become a leading cause of disability worldwide. Astrocyte activation in the spinal cord plays an important role in the maintenance of latent sensitization of dorsal horn neurons in LBP. However, the role of spinal c-Jun N-terminal kinase (JNK) in astrocytes in modulating pain behavior of LBP model rats and its neurobiological mechanism have not been elucidated. Here, we investigate the role of the JNK signaling pathway on hypersensitivity and anxiety-like behavior caused by repetitive nerve growth factor (NGF) injections in male non-specific LBP model rats. LBP was produced by two injections (day 0, day 5) of NGF into multifidus muscle of the low backs of rats. We observed prolonged mechanical and thermal hypersensitivity in the low backs or hindpaws. Persistent anxiety-like behavior was observed, together with astrocyte, p-JNK, and neuronal activation and upregulated expression of monocyte chemoattractant protein-1 (MCP-1), and chemokine (C-X-C motif) ligand 1 (CXCL1) proteins in the spinal L2 segment. Second, the JNK inhibitor SP600125 was intrathecally administrated in rats from day 10 to day 12. It attenuated mechanical and thermal hypersensitivity of the low back or hindpaws and anxiety-like behavior. Meanwhile, SP600125 decreased astrocyte and neuronal activation and the expression of MCP-1 and CXCL1 proteins. These results showed that hypersensitivity and anxiety-like behavior induced by NGF in LBP rats could be attenuated by the JNK inhibitor, together with downregulation of spinal astrocyte activation, neuron activation, and inflammatory cytokines. Our results indicate that intervening with the spinal JNK signaling pathway presents an effective therapeutic approach to alleviating LBP.

Atherogenic Effect of Homocysteine, a Biomarker of Inflammation and Its Treatment.

Hyperhomocysteinemia (HHcy) is an independent risk factor for atherosclerosis. Ischemic stroke and heart disease, coronary heart disease, and cardiovascular disease are events resulting from long-lasting and silent atherosclerosis. This paper deals with the synthesis of homocysteine (Hcy), causes of HHcy, mechanism of HHcy-induced atherosclerosis, and treatment of HHcy. Synthesis and metabolism of Hcy involves demethylation, transmethylation, and transsulfuration, and these processes require vitamin B 6 and vitamin B 12 folic acid (vitamin B 9 ). Causes of HHcy include deficiency of vitamins B 6 , B 9 , and B 12 , genetic defects, use of smokeless tobacco, cigarette smoking, alcohol consumption, diabetes, rheumatoid arthritis, low thyroid hormone, consumption of caffeine, folic acid antagonist, cholesterol-lowering drugs (niacin), folic acid antagonist (phenytoin), prolonged use of proton pump inhibitors, metformin, and hypertension. HHcy-induced atherosclerosis may be mediated through oxidative stress, decreased availability of nitric oxide (NO), increased expression of monocyte chemoattractant protein-1, smooth muscle cell proliferation, increased thrombogenicity, and induction of arterial connective tissue. HHcy increases the generation of atherogenic biomolecules such as nuclear factor-kappa B, proinflammatory cytokines (IL-1β, IL-6, and IL-8), cell adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selection), growth factors (IGF-1 and TGF-β), and monocyte colony-stimulating factor which lead to the development of atherosclerosis. NO which is protective against the development of atherosclerosis is reduced by HHcy. Therapy with folic acid, vitamin B 6 , and vitamin B 12 lowers the levels of Hcy, with folic acid being the most effective. Dietary sources of folic acid, vitamin B 6 , vitamin B 12 , omega-3 fatty acid, and green coffee extract reduce Hcy. Abstaining from drinking coffee and alcohol, and smoking also reduces blood levels of Hcy. In conclusion, HHcy induces atherosclerosis by generating atherogenic biomolecules, and treatment of atherosclerosis-induced diseases may be by reducing the levels of Hcy.

Macrophage IL-1β mediates atrial fibrillation risk in diabetic mice.

Diabetes mellitus (DM) is an independent risk factor for atrial fibrillation (AF). The mechanisms underlying DM-associated AF are unclear. AF and DM are both related to inflammation. We investigated whether DM-associated inflammation contributed to AF risk. Mice were fed with high-fat diet to induce type II DM and were subjected to IL-1β antibodies, macrophage depletion by clodronate liposomes, a mitochondrial antioxidant (mitoTEMPO), or a cardiac ryanodine receptor 2 (RyR2) stabilizer (S107). All tests were performed at 36-38 weeks of age. DM mice presented with increased AF inducibility, enhanced mitochondrial reactive oxygen species (mitoROS) generation, and activated innate immunity in the atria, as evidenced by enhanced monocyte chemoattractant protein-1 (MCP-1) expression, macrophage infiltration, and IL-1β levels. Signs of aberrant RyR2 Ca2+ leak were observed in the atria of DM mice. IL-1β neutralization, macrophage depletion, and exposure to mitoTEMPO and S107 significantly ameliorated the AF vulnerability in DM mice. Atrial overexpression of MCP-1 increased AF occurrence in normal mice through the same mechanistic signaling cascade as observed in DM mice. In conclusion, macrophage-mediated IL-1β contributed to DM-associated AF risk through mitoROS modulation of RyR2 Ca2+ leak.

TIMP-1 Promotes Expression of MCP-1 and Macrophage Migration by Inducing Fli-1 in Experimental Liver Fibrosis.

Tissue inhibitor of metalloproteinase-1 (TIMP-1) plays a role in the excessive generation of extracellular matrix in liver fibrosis. This study aimed to explore the pathways through which TIMP-1 controls monocyte chemoattractant protein-1 (MCP-1) expression and promotes hepatic macrophage recruitment. Liver fibrosis was triggered through carbon tetrachloride, and an adeno-associated virus containing small interfering RNA targeting TIMP-1 (siRNA-TIMP-1) was administered to both rats and mice. We assessed the extent of fibrosis and macrophage recruitment. The molecular mechanisms regulating macrophage recruitment by TIMP-1 were investigated through transwell migration assays, luciferase reporter assays, the use of pharmacological modulators, and an analysis of extracellular vesicles (EVs). siRNA-TIMP-1 alleviated carbon tetrachloride-induced liver fibrosis, reducing macrophage migration and MCP-1 expression. Co-culturing macrophages with hepatic stellate cells (HSCs) post-TIMP-1 downregulation inhibited macrophage migration. In siRNA-TIMP-1-treated HSCs, microRNA-145 (miRNA-145) expression increased, while the expression of Friend leukemia virus integration-1 (Fli-1) and MCP-1 was inhibited. Downregulation of Fli-1 led to decreased MCP-1 expression, whereas Fli-1 overexpression increased MCP-1 expression within HSCs. Transfection with miRNA-145 mimics reduced the expression of both Fli-1 and MCP-1, while miRNA-145 inhibitors elevated the expression of both Fli-1 and MCP-1 in HSCs. miRNA-145 bound directly to the 3'-UTR of Fli-1, and miRNA-145-enriched EVs secreted by HSCs after TIMP-1 downregulation influenced macrophage recruitment. TIMP-1 induces Fli-1 expression through miRNA-145, subsequently increasing MCP-1 expression and macrophage recruitment. MiRNA-145-enriched EVs from HSCs can transmit biological information and magnify the function of TIMP-1.

Effects of Yacon Leaf Extract on MCP-1 and IL-10 Expressions and Macrophage Phenotypes in CKD Mouse Model

Macrophages are essential in tissue homeostasis and immunity, but also contribute to disease development and progression. Chronic kidney disease (CKD) is characterized by interstitial infiltration of macrophages, the density of which correlates inversely with kidney survival. Studies have shown that yacon (Smallanthus sonchifolius) has beneficial effects on CKD. Therefore, this study aimed to investigate the effects of yacon leaf extract on mice with subtotal nephrectomy by evaluating the M1 and M2 macrophage counts and mRNA expressions of monocyte chemoattractant protein-1 (MCP-1 and IL-10. The mice were randomly divided into five groups: SO (negative control: underwent sham operation), SN (positive control: underwent subtotal nephrectomy), and yacon-treated groups: YK1, YK2, and YK3 (underwent subtotal nephrectomy, given peroral yacon leaf extract for 14 days with doses of 24,5 mg/kgBW/day, 49 mg/kgBW/day, and 98 mg/kgBW/day, respectively). The macrophage subtypes were assessed using immunohistochemistry anti-CD68 for M1 and anti-Arginase I for M2. MCP-1 and IL-10 mRNA expressions were analyzed using semi-quantitative PCR. Results showed that yacon leaf extract could significantly lower the M2 macrophage count (p&lt;0.001) and the mRNA expressions of MCP-1 and IL-10 in all yacon-treated groups when compared to the SN group. However, the M1 macrophage count was only lower in the YK2 group (p=0.009). In conclusion, the administration of yacon leaf extract could attenuate kidney injury by lowering the macrophage count and the expression of MCP-1 and IL-10.

#2349 Lysyl oxidase-like 2 inhibitor ameliorates tubulointerstitial fibrosis and albuminuria in cyclosporine induced nephropathy

Abstract Background and Aims Lysyl oxidase-like 2 (LOXL2), an amine oxidase, contributes to fibrotic scarring in the tissue by facilitating collagen cross-linking. Recent data demonstrated upregulation of lysyl oxidase and LOXL2 in the fibrotic kidneys after administration of cylosporine A (CsA). Thus, inhibition of LOXL2 may render therapeutic effects against CsA-induced nephropathy by ameliorating tubulointerstitial fibrosis. Method Low salt fed CD-1 mice were administered saline or CsA (15 mg/kg/day, intraperitoneally) for 8 weeks. At 4 weeks, CsA-treated animals were divided into 2 groups respectively and treated with: (1) vehicle, (2) LOXL2 inhibitor (10 mg/kg/day, gavage feeding) for another 4 weeks up to 8 weeks. We explored the reduction of tubulointerstitial fibrosis as well as albuminuria with administration of LOXL2 inhibitor in CsA nephropathy mouse model. Results CsA administration significantly increased the levels of serum creatinine (10.0 ± 1.2 vs. 28.4 ± 4.3, p = 0.02), tubular injury scores (0.1 ± 0.2 vs. 3.6 ± 1.3, p = 0.03), tubulointerstitial fibrosis (Sirius red positive area, 14 ± 6% vs. 204 ± 43%, p = 0.01), F4/80 positive inflammatory cell infiltration in mouse kidney (2 ± 1 vs. 21 ± 4, p = 0.001). These changes were associated with upregulated mRNA expression of LOXL2, TGF-β1, and monocyte chemoattractant protein-1 (MCP-1). Administration of LOXL2 inhibitor significantly suppressed the expression of alpha-SMA and collagen 1A, intrarenal F4/80 positive inflammatory cell infiltrations (21 ± 4 vs. 14 ± 2, p = 0.001) and improved tubular injury scores (3.6 ± 1.3 vs. 1.6 ± 1.1, p = 0.02). Moreover, LOXL2 inhibitor effectively reduced albuminuria excretion (46 ± 4 vs. 22 ± 6, p = 0.02). Conclusion Our results suggest that LOXL2 inhibitor treatment can attenuate CsA nephropathy progression and LOXL2 may be a potential therapeutic target in CsA nephropathy.

Dysregulation of lncRNA MALAT1 Contributes to Lung Cancer in African Americans by Modulating the Tumor Immune Microenvironment.

African American (AA) populations present with notably higher incidence and mortality rates from lung cancer in comparison to other racial groups. Here, we elucidated the contribution of long non-coding RNAs (lncRNAs) in the racial disparities and their potential clinical applications in both diagnosis and therapeutic strategies. AA patients had elevated plasma levels of MALAT1 and PVT1 compared with cancer-free smokers. Incorporating these lncRNAs as plasma biomarkers, along with smoking history, achieved 81% accuracy in diagnosis of lung cancer in AA patients. We observed a rise in MALAT1 expression, correlating with increased levels of monocyte chemoattractant protein-1 (MCP-1) and CD68, CD163, CD206, indicative of tumor-associated macrophages in lung tumors of AA patients. Forced MALAT1 expression led to enhanced growth and invasiveness of lung cancer cells, both in vitro and in vivo, accompanied by elevated levels of MCP-1, CD68, CD163, CD206, and KI67. Mechanistically, MALAT1 acted as a competing endogenous RNA to directly interact with miR-206, subsequently affecting MCP-1 expression and macrophage activity, and enhanced the tumorigenesis. Targeting MALAT1 significantly reduced tumor sizes in animal models. Therefore, dysregulated MALAT1 contributes to lung cancer disparities in AAs by modulating the tumor immune microenvironment through its interaction with miR-206, thereby presenting novel diagnostic and therapeutic targets.

Antiperiodontitis impact of extract from edible herb Aster glehni and its bioactive compound, 3,5-dicaffeolyquinic acid

Periodontitis is a chronic oral disease caused by periodontal pathogenic bacteria, such as Porphyromonas gingivalis. The lipopolysaccharide of P. gingivalis (PgLPS) is a crucial virulence factor that contributes to the pathogenesis of periodontitis. The present study investigated the anti-inflammatory effects of extract from Aster glehni (AGE), a region-specific edible herb in Korea, and its main bioactive compound, 3,5-dicaffeolyquinic acid (3,5-DCQA), on PgLPS-induced inflammatory responses and the associated intracellular mechanisms. AGE significantly suppressed the expression of interleukin (IL)-1β and IL-6, while moderately inhibiting monocyte chemoattractant protein-1 (MCP-1) expression at both mRNA and protein levels in RAW 264.7 cells stimulated by PgLPS. Furthermore, AGE effectively attenuated mitogen-activated protein kinase (MAPK) phosphorylation and nuclear factor-κB (NF-κB) activation induced by PgLPS. In contrast, 3,5-DCQA partially inhibited the expression of IL-1β, IL-6, and MCP-1 at both mRNA and protein levels. Additionally, 3,5-DCQA appeared to attenuate MAPK phosphorylation and NF-κB activation without exhibiting clear dose-dependency. Moreover, AGE dose-dependently attenuated TLR2 and TLR4 expression, while 3,5-DCQA decreased both TLR2 and TLR4 expression without clear dose-dependency. AGE demonstrated effective inhibition of PgLPS-induced inflammatory responses, with 3,5-DCQA playing a partial role in the inhibitory potential of AGE.

Novel Fermentates Can Enhance Key Immune Responses Associated with Viral Immunity.

Fermented foods have long been known to have immunomodulatory capabilities, and fermentates derived from the lactic acid bacteria of dairy products can modulate the immune system. We have used skimmed milk powder to generate novel fermentates using Lb. helveticus strains SC234 and SC232 and we demonstrate here that these fermentates can enhance key immune mechanisms that are critical to the immune response to viruses. We show that our novel fermentates, SC234 and SC232, can positively impact on cytokine and chemokine secretion, nitric oxide (NO) production, cell surface marker expression, and phagocytosis in macrophage models. We demonstrate that the fermentates SC234 and SC232 increase the secretion of cytokines IL-1β, IL-6, TNF-α, IL-27, and IL-10; promote an M1 pro-inflammatory phenotype for viral immunity via NO induction; decrease chemokine expression of Monocyte Chemoattractant Protein (MCP); increase cell surface marker expression; and enhance phagocytosis in comparison to their starting material. These data suggest that these novel fermentates have potential as novel functional food ingredients for the treatment, management, and control of viral infection.