Monocyte Chemoattractant Protein-1 Protein Research Articles

Inhibitory Effects of Eicosapentaenoic Acid on Vascular Endothelial Growth Factor-Induced Monocyte Chemoattractant Protein-1, Interleukin-6, and Interleukin-8 in Human Vascular Endothelial Cells.

Vascular endothelial growth factor (VEGF) induces monocyte chemoattractant protein-1 (MCP-1) and plays an important role in vascular inflammation and atherosclerosis. We investigated the mechanisms of VEGF-induced MCP-1 expression and the effects of eicosapentaenoic acid (EPA) in human umbilical vein endothelial cells (HUVECs). Real-time reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) demonstrated that VEGF enhanced MCP-1 gene expression and protein secretion in HUVECs. Western immunoblot analysis revealed that VEGF induced the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and inhibitor of nuclear factor (NF)-κB (IκB). Treatment with pharmacological inhibitors of p38 MAPK (SB203580) or NF-κB (BAY11-7085) significantly suppressed VEGF-induced MCP-1 in HUVECs. EPA inhibited VEGF-induced MCP-1 mRNA, protein secretion, phosphorylation of p38 MAPK, and the translocation of phospho-p65 to the nucleus. Additionally, VEGF also stimulated gene expressions of interleukin (IL)-6 and IL-8, which were suppressed by SB203580, BAY11-7085, and EPA. The present study has demonstrated that VEGF-induced activation of MCP-1, IL-6, and IL-8 involves the p38 MAPK and NF-κB signaling pathways and that EPA inhibits VEGF-induced MCP-1, IL-6, and IL-8 via suppressing these signaling pathways. This study supports EPA as a beneficial anti-inflammatory and anti-atherogenic drug to reduce the VEGF-induced activation of proinflammatory cytokine and chemokines.

Circulating Monocyte Chemoattractant Protein-1 (MCP-1) in Patients with Primary Biliary Cholangitis.

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease that leads to the destruction of the intrahepatic bile ducts. While the inflammatory process can be mediated by monocyte chemotactic protein-1 (MCP-1), the importance of circulating MCP-1 as a biomarker is unclear. Our aim was to assess the diagnostic significance of the serum concentrations of MCP-1 in PBC patients. We compared circulating MCP-1 with biochemical, immunological and histological parameters. Serum samples were collected from 120 PBC patients, 60 pathologic controls and 30 healthy donors. MCP-1 levels were determined by using commercial enzyme-linked immunosorbent assay (ELISA). Elevated serum MCP-1 levels were detected in 66% of PBC patients with a specificity of 97%. Significantly higher levels of MCP-1 protein were found in the sera of patients with PBC than in the group of healthy individuals-410.2 pg/mL vs. 176.0 pg/mL, p < 0.01). Patients with higher concentrations of alkaline phosphatase also had higher levels of MCP-1 (r = 0.4, p < 0.01). In accordance with Ludwig's classification, a positive correlation of serum MCP-1 concentration with the degree of fibrosis was observed, OR = 6.1, p = 0.0003. We compared the MCP-1 with procollagen type III, hyaluronic acid (HA), FIB-4 index, APRI and collagen type IV when predicting the advance of liver fibrosis. Circulating MCP-1 is better correlated with liver fibrosis and is also associated with the occurrence of specific antimitochondrial autoantibodies and specific anti-nuclear autoantibodies-anti-gp210. MPC-1 can be considered to be a tool for diagnosing the degree of fibrosis in PBC, and combinations of MCP-1 and other specific biomarkers could support the diagnosis of PBC.

Effect of Flavonoids on MCP-1 Expression in Human Coronary Artery Endothelial Cells and Impact on MCP-1-Dependent Migration of Human Monocytes.

The monocyte chemoattractant protein-1 (MCP-1), also known as chemokine (CC motif) ligand 2 (CCL2), is involved in the formation, progression, and destabilization of atheromatous plaques. Flavonoids, found in fruits and vegetables, have been associated with various health-promoting properties, including antioxidant, anti-inflammatory, and cardioprotective effects. In the present study, the flavonoids quercetin, kaempferol, and luteolin, but not cannflavin A, were shown to substantially inhibit interleukin (IL)-1β-induced MCP-1 mRNA and protein expression in human coronary artery endothelial cells (HCAEC). At the functional level, conditioned medium (CM) from IL-1β-stimulated HCAEC caused an increase in the migration of THP-1 monocytes compared with CM from unstimulated HCAEC. However, this induction was suppressed when IL-1β-treated HCAEC were coincubated with quercetin, kaempferol, or luteolin. The functional importance of MCP-1 in IL-1β-induced monocyte migration was supported by experiments showing that neutralization of MCP-1 in the CM of IL-1β-treated HCAEC led to a significant inhibition of migration. In addition, a concentration-dependent induction of monocyte migration in the presence of recombinant MCP-1 was demonstrated. Collectively, the flavonoids quercetin, kaempferol, and luteolin were found to exert potential antiatherogenic effects in HCAEC, challenging further studies with these compounds.

The SMAC mimetic birinapant alleviates lipopolysaccharide-induced acute lung injury by inhibiting MAPK signaling

The second mitochondria-derived activator of caspases (SMAC) mimetic birinapant attenuated liver injury by inhibited the degradation of tumor necrosis factor receptor-associated factor 3 (TRAF3) and activation of mitogen-activated protein kinase (MAPK) signaling pathway in liver macrophage, but its role in LPS induced acute lung injury (ALI) is not understood. The present study was to investigate the effects of birinapant on ALI and its possible mechanism. A dose of birinapant (30 mg/kg) or a vehicle was administered intravenously 24 hours before LPS (100 μg) stimulation in mice. The levels of TNF-α, IL-6 and IL-1β in bronchoalveolar lavage fluid (BALF) were measured by ELISA. The infiltrated macrophages and expression of monocyte chemoattractant protein-1 (MCP-1) was determined by immunohistochemistry staining in the lung tissues. The JNK and p38 MAPK activation, protein expression and K48-linked polyubiquitination of TRAF3 were determined in alveolar macrophage cell line (MH-S cells) after 1μg/ml LPS stimulation. The results showed that the birinapant down-regulated the levels of TNF-α, IL-6 and IL-1β in the BALF. In addition, birinapant markedly inhibited macrophages infiltration and MCP-1 protein expression in lung tissues. At last, birinapant suppressed the MAPKsignaling pathway and K48-linked ubiquitinated degradation of TRAF3 in MH-S cells after LPS administration. In conclusion, the results proved that birinapant protected against LPS-induced ALI through inhibiting MAPK activation and K48-linked ubiquitination of TRAF3 in alveolar macrophages.

SAT381 Effect of Obesity on Androgen-induced Splenic Dysregulation in Polycystic Ovary Syndrome

Abstract Disclosure: S. Rezq: None. J. Basnet: None. A.M. Huffman: None. L.L. Yanes Cardozo: None. D.G. Romero: None. Background: Polycystic ovary syndrome (PCOS) is characterized by ovarian dysfunction and hyperandrogenism. Women with PCOS exhibit low-grade systemic inflammation, obesity, and immune dysregulation. The spleen plays an important role in immune function and physiological inflammation regulation. Androgens and obesity negatively impact splenic structure and function. However, the effect of androgens on spleen architecture and function and its modulation by obesogenic diet is unknown in PCOS. Using a well-established PCOS model of hyperandrogenemia we aim to test the hypothesis that androgens cause splenic dysregulations that are exacerbated by obesity. Methods: Three-week-old female mice were treated with the androgen dihydrotestosterone (DHT, 8 mg, s.c) or vehicle. Animals were fed a high-fat diet (HFD; 60% kcal fat) or a low-fat diet (LFD; 10% kcal fat) for 90 days (n=6-8/group). Body composition (EchoMRI) and spleen weight were assessed. Splenic mRNA or protein expression of multiple immune cells/regulatory markers such as chemokines ligands Cxcl12 and Lymphotoxin B (Ltb), and their corresponding receptors C-X-C chemokine receptor type 4 (CXCR4) and Ltb receptor (LTBR), as well as the chemokine monocyte chemoattractant protein-1 (MCP-1), proliferation markers Csf1, Csf2, and Csf3, the adhesion molecule Vcam1, and extracellular matrix (ECM) remodeling marker Coch were assessed by RT-qPCR or Western blot. Additionally, splenic androgen receptor (AR) protein expression was measured by Western blot, while the inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor (TNF-α) were detected by ELISA. Results: DHT significantly (p&amp;lt;0.05) increased fat mass (6.2 ± 0.5 vs. 3.4 ± 0.3 g) and spleen weight (11.9 ± 1.6 vs. 4.9 ± 0.22 g) in LFD-fed mice, which was exacerbated by HFD. DHT-mediated splenomegaly was associated with a significant (p&amp;lt;0.05) decrease in the expression of AR (90%), the chemokine Cxcl12 (70-80%), the proliferation markers Csf1 and Csf2 (65-66%), and the ECM marker Coch (70%) in mice that were fed on both diets. PCOS mice had significantly (p&amp;lt;0.05) higher CXCR4 (4.4-4.7-fold) and LTBR (5.7-7.6-fold) expression, independent of diet. Interestingly, only the HFD-fed PCOS mice had significantly (p&amp;lt;0.05) lower splenic Vcam1 (76%), IL-6 (25%), and TNF-α (4.6 ± 0.2 vs. 5.6 ± 0.2 pg/μg protein) levels, while they also had higher MCP-1 protein levels (2-fold, p&amp;lt;0.05). Conclusion and significance: Our data show that androgens cause splenic structural and molecular alterations that are modulated by obesity. These findings could explain PCOS-associated immune dysregulation that is more predominant in obese women with PCOS. The study highlights the spleen as a novel key target organ of androgen-mediated pathology in PCOS. Furthermore, our study suggests that weight loss could potentially attenuate androgen-associated splenic derangements in PCOS. Presentation Date: Saturday, June 17, 2023

Unravelling the Influence of Demographic and Lifestyle Factors on Monocyte Chemoattractant Protein-1 in Diabetic Retinopathy Patients

Objectives: To determine the association of Monocyte chemoattractant protein-1 (MCP-1) level with Age, blood glucose level, Exercise, Gender and Smoking in diabetic retinopathy patients. Study Design and settings: A case-control study was carried in the physiology department at the Jinnah Postgraduate Medical Centre in Karachi From April 2019 to October 2020. Methodology: One hundred people were divided into four groups which were; Group D (n=25) were healthy normal individuals; Group C (n=25) diabetic patient's with moderate retinopathy; Group B (n=25) diabetic patient's with mild retinopathy while Group A (n=25) diabetic patients with no retinopathy. Every participant was checked for blood sugar level, retinoscopy through slit lamp examination and serum MCP-1 level. The association was made between diabetic retinopathy, MCP-1 protein levels, age, gender, smoking and exercise. Results: MCP-1 levels are significantly greater in diabetic males with moderate retinopathy compared to diabetic females with moderate retinopathy (p-value 0.042). Similarly, smoking is associated with the elevation of MCP-1 levels in diabetic patients with moderate retinopathy (p-value 0.05). Exercise has no significant effect on MCP-1 levels in all groups. An increase in age, HbA1C, fasting and random blood glucose levels were significantly correlated with MCP-1 levels ( pvalue 0.000) Conclusion: It is concluded from the study that an advance in age and an increase in blood glucose level are associated with an increased level of MCP-1 protein. Moreover, Male gender and smoking are also associated with enhanced MCP- 1 levels in diabetic patients with moderate retinopathy.

Intrarenal renin–angiotensin system activation and macrophage infiltrations in pediatric chronic glomerulonephritis

BackgroundThe current study tested the hypothesis that urinary angiotensinogen (UAGT) and urinary monocyte chemoattractant protein-1 (UMCP-1) levels provide a specific index of intrarenal renin–angiotensin system (RAS) status and the degree of infiltration of macrophages associated with RAS blockade and immunosuppressant treatment in pediatric patients with chronic glomerulonephritis.MethodsWe measured baseline UAGT and UMCP-1 levels to examine the correlation between glomerular injury in 48 pediatric chronic glomerulonephritis patients before treatment. Furthermore, we performed immunohistochemical analysis of angiotensinogen (AGT) and CD68 in 27 pediatric chronic glomerulonephritis patients treated with RAS blockades and immunosuppressants for 2 years. Finally, we examined the effects of angiotensin II (Ang II) on monocyte chemoattractant protein-1 (MCP-1) expression in cultured human mesangial cells (MCs).ResultsBaseline UAGT and UMCP-1 levels positively correlated with urinary protein levels, scores for mesangial hypercellularity, rate of crescentic formation, and expression levels of AGT and CD68 in renal tissues (p < 0.05). UAGT and UMCP-1 levels were significantly decreased after RAS blockade and immunosuppressant treatment (p < 0.01), which was accompanied by AGT and CD68 (p < 0.01), as well as the magnitude of glomerular injury. Cultured human MCs showed increased MCP-1 messenger ribonucleic acid and protein levels after Ang II treatment (p < 0.01).ConclusionsThe data indicates that UAGT and UMCP-1 are useful biomarkers of the degree of glomerular injury during RAS blockade and immunosuppressant treatment in pediatric patients with chronic glomerulonephritis.

Transforming growth factor-β2 is associated with atherosclerotic plaque stability and lower risk for cardiovascular events.

Transforming growth factor-beta (TGF-β) exists in three isoforms TGF-β1, -β2 and -β3. TGF-β1 has been suggested to be important for maintaining plaque stability, yet the role of TGF-β2 and -β3 in atherosclerosis remains to be investigated. This study explores the association of these three isoforms of TGF-β with plaque stability in the human atherosclerotic disease. TGF-β1, -β2 and -β3 proteins were quantified in 223 human carotid plaques by immunoassays. Indications for the endarterectomy were: symptomatic carotid plaque with stenosis >70% or without symptoms and >80% stenosis. Plaque mRNA levels were assessed by RNA sequencing. Plaque components and extracellular matrix were measured histologically and biochemically. Matrix metalloproteinases were measured with ELISA. Monocyte chemoattractant protein-1 (MCP-1) was measured with immunoassays. The effect of TGF-β2 on inflammation and protease activity was investigated in vitro using THP-1 and RAW264.7 macrophages. Patients were followed longitudinally for cardiovascular events.TGF-β2 was the most abundant isoform and was increased at both protein and mRNA levels in asymptomatic plaques. TGF-β2 was the main determinant separating asymptomatic plaques in an Orthogonal Projections to Latent Structures Discriminant Analysis. TGF-β2 correlated positively to features of plaque stability and inversely to markers of plaque vulnerability. TGF-β2 was the only isoform inversely correlated to the matrix-degrading matrix metalloproteinase-9 and inflammation in the plaque tissue. In vitro, TGF-β2 pre-treatment reduced MCP-1 gene and protein levels as well as matrix metalloproteinase-9 gene levels and activity. Patients with plaques with high TGF-β2 levels had a lower risk to suffer from future cardiovascular events. TGF-β2 is the most abundant TGF-β isoform in human plaques and may maintain plaque stability by decreasing inflammation and matrix degradation.

Robust therapeutic effects on COVID-19 of novel small molecules: Alleviation of SARS-CoV-2 S protein induction of ACE2/TMPRSS2, NOX2/ROS, and MCP-1.

While new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) constantly emerge to prolong the pandemic of COVID-19, robust and safe therapeutics are in urgent need. During the previous and ongoing fight against the pandemic in China, Traditional Chinese Medicine (TCM) has proven to be markedly effective in treating COVID-19. Among active ingredients of TCM recipes, small molecules such as quercetin, glabridin, gallic acid, and chrysoeriol have been predicted to target viral receptor angiotensin-converting enzyme 2 (ACE2) via system pharmacology/molecular docking/visualization analyses. Of note, endothelial dysfunction induced by oxidative stress and inflammation represents a critical mediator of acute respiratory distress syndrome (ARDS) and multi-organ injuries in patients with COVID-19. Hence, in the present study, we examined whether quercetin, glabridin, gallic acide and chrysoeriol regulate viral receptors of ACE2 and transmembrane serine protease 2 (TMPRSS2), redox modulator NADPH oxidase isoform 2 (NOX2), and inflammatory protein of monocyte chemoattractant protein-1 (MCP-1) in endothelial cells to mediate therapeutic protection against COVID-19. Indeed, quercetin, glabridin, gallic acide and chrysoeriol completely attenuated SARS-CoV-2 spike protein (S protein)-induced upregulation in ACE2 protein expression in endothelial cells. In addition, these small molecules abolished S protein upregulation of cleaved/active form of TMPRSS2, while native TMPRSS2 was not significantly regulated. Moreover, these small molecules completely abrogated S protein-induced upregulation in NOX2 protein expression, which resulted in alleviated superoxide production, confirming their preventive efficacies against S protein-induced oxidative stress in endothelial cells. In addition, treatment with these small molecules abolished S protein induction of MCP-1 expression. Collectively, our findings for the first time demonstrate that these novel small molecules may be used as novel and robust therapeutic options for the treatment of patients with COVID-19, via effective attenuation of S protein induction of endothelial oxidative stress and inflammation.

1,25-dihydroxyvitamin D3 ameliorates high glucose-mediated proliferation, migration, and MCP-1 secretion of vascular smooth muscle cells by inhibiting MAPK phosphorylation

ObjectivesTo explore the impacts of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the proliferation, migration, and monocyte chemoattractant protein-1 (MCP-1) secretion of vascular smooth muscle cells (VSMCs) in a high glucose environment and its possible mechanism.MethodsWe extracted VSMCs from the thoracic aorta of a male Sprague–Dawley rats before culturing them in a 25-mM glucose-containing medium in the presence or absence of 1,25(OH)2D3 (10−9 –10−7 M). Cell proliferation was determined by bromodeoxyuridine incorporation assays. Subsequently, cell migratory capacity was examined by performing a transwell assay. An enzyme-linked immunosorbent assay was conducted to assess MCP-1 levels. Protein levels of matrix metalloproteinase-9 (MMP-9), mitogen-activated protein kinases (MAPKs), cyclin D1, and phosphorylated MAPKs were determined by immunoblotting.Results1,25(OH)2D3 significantly suppressed the proliferation, migration, and MCP-1 secretion of VSMCs mediated by high glucose in a dose-dependent manner, diminished the enhanced protein expression of MMP-9 and cyclin D1, and attenuated MAPK phosphorylation. The p38 inhibitor SB203580 and ERK1/2 inhibitor PD98059 suppressed high glucose-mediated upregulation of MMP-9 and cyclin D1 protein expression and MCP-1 secretion, respectively.Conclusions1,25(OH)2D3 ameliorates high glucose-mediated proliferation, migration, and MCP-1 secretion of VSMCs by inhibiting MAPK phosphorylation, implying a potential therapeutic approach using 1,25(OH)2D3 for diabetic macrovascular complications.

Dual Beneficial Effects of Methylnissolin-3-O-β-d-Glucopyranoside on Obesity-Induced Inflammatory Responses in Adipocyte-Macrophage Co-Culture.

Methylnissolin-3-O-β-d-glucopyranoside (MNG) is a pterocarpan analog, which protects EA.hy926 cells against oxidative damage through the Nrf2/HO-1 pathway. However, the effects of MNG on obesity-induced inflammatory responses in adipocyte-macrophage co-culture remain unclear. A differentiated murine preadipocyte cell line (3T3-L1) was co-cultured with a murine macrophage cell line (RAW264.7). Intracellular lipid accumulation was determined using Oil Red O staining. Western blotting was performed to investigate the expression of adipogenesis- and inflammation-associated proteins. Cell culture supernatants were assayed using ELISA kits to measure the levels of proinflammatory cytokines such as interleukin 6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1). MNG inhibited lipid accumulation and the production of IL-6 and MCP-1 in the 3T3-L1 and RAW264.7 cell co-culture. Moreover, MNG inhibited the protein expression of CCAAT/enhancer-binding protein alpha (C/EBPα), C/EBPβ, peroxisome proliferator-activated receptor γ (PPARγ), cyclooxygenase 2 (COX-2), and inducible nitric oxide synthase (iNOS) under the same co-culture conditions. MNG also inhibited IL-6 and MCP-1 production compared with the co-culture control. These findings demonstrate that MNG inhibited lipid accumulation and inflammatory response by downregulating IL-6 and MCP-1 production and protein expression of C/EBPβ, C/EBPα, PPARγ, COX-2, and iNOS in co-culture conditions with 3T3-L1 and RAW264.7 cells. These results suggest that MNG may be beneficial in preventing obesity-related inflammatory status.

MicroRNA-122-5p regulates coagulation and inflammation through MASP1 and HO-1 genes.

MiR-122-5p is a diagnostic and prognostic biomarker of sepsis and is correlated with coagulation abnormalities in sepsis. However, its functional aspects remain unknown. This study applied bioinformatics analysis to evaluate the coagulation-related target genes for miR-122-5p. THP-1, HUVEC, and LO-2 cell lines were used in this study. MiR-122-5p mimics were transfected into the three previously mentioned cell lines, which helped in detecting mRNA and protein levels by qRT-PCR and western blotting, respectively. Serum samples from 84 sepsis patients were collected to evaluate target gene code proteins. The protein and mRNA levels of Heme oxygenase1(HO-1), IL-1β, IL-6, monocyte chemoattractant protein 1(MCP-1), and TNF-α were also evaluated in three cell lines. Mannan binding lectin serine peptidase 1(MASP1) was a direct target gene of miR-122-5p, and levels of MASP1, C3, and C4 were all significantly lower in the sepsis with disseminated intravascular coagulopathy (DIC) group than in the sepsis without DIC group. MiR-122-5p mimics could down-regulate HO-1 in the three cell lines. HO-1, IL-1β, IL-6, MCP-1, and TNF-α gene and protein levels were decreased after miR-122-5p mimics were added. MiR-122-5p regulated coagulation and inflammation through MASP1 and HO-1, respectively.

Antiatherosclerotic effects of corilagin via suppression of the LOX-1/MyD88/NF-κB signaling pathway in vivo and in vitro.

Corilagin, a natural polyphenol compound isolated from Phyllanthus urinaria L., exerts various pharmacological effects, such as antihyperglycemic, antitumor, and antioxidative stress properties, but the mechanisms underlying the antiatherosclerotic effects of corilagin have not been entirely elucidated. In the present study, we investigated the antiatherosclerotic effects of corilagin using a high-fat diet (HFD)-induced atherosclerotic rabbit model and ox-LDL-induced vascular smooth muscle cells (VSMCs) and explored the underlying molecular mechanisms. The serum lipid levels were measured through an enzymatic colorimetric assay. A histological analysis of rabbit aortas was performed after hematoxylin-eosin and oil red O staining. The proliferation of ox-LDL-induced VSMCs was detected using MTT assays, and the migration of cells was determined by wound scratch assays. In addition, the mRNA and protein expression levels of lectin-like ox-LDL receptor-1 (LOX-1), myeloid differentiation factor 88 (MyD88), nuclear factor-kappa B (NF-κB), monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor α (TNF-α) were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting assays. Our results indicate that corilagin significantly reduced the serum levels of TC, TG and LDL-C, increased the HDL-C levels, decreased the intimal thickening in the thoracic aorta, and reduced the formation of foam cells in an HFD-induced rabbit atherosclerosis model. Moreover, corilagin suppressed the proliferation and migration of ox-LDL-induced VSMCs and reduced LOX-1, MyD88, NF-κB, MCP-1, and TNF-α mRNA and protein expression in vivo and in vitro. These data demonstrate that corilagin exerts antiatherosclerotic effects in vivo and in vitro and that the mechanisms may be closely associated with downregulation of the LOX-1/MyD88/NF-κB pathway.

18β-Glycyrrhetinic acid ameliorates endoplasmic reticulum stress-induced inflammation in pulmonary arterial hypertension through PERK/eIF2α/NF-κB signaling.

Endoplasmic reticulum stress (ERS)-induced inflammation participates in the occurrence of pulmonary arterial hypertension (PAH) by promoting pulmonary vascular remodeling, which involved in the activation of PERK/eIF2α/NF-κB signaling pathway. 18β-Glycyrrhetinic acid (18β-GA) has been found efficacious for attenuating PAH through its anti-remodeling effects in our previous research and it remains unclear whether 18β-GA has an effect on the remodeling caused by ERS-induced inflammation. In this study, we made observations in monocrotaline-induced PAH rats and found improvement of hemodynamic and histopathological parameters, decreases in the right ventricular hypertrophy index, and alleviation of pulmonary vascular remodeling after 18β-GA administration in vivo. Moreover, 18β-GA could significantly inhibit the proliferation and DNA synthesis of human pulmonary arterial smooth muscle cells (HPASMCs) induced by platelet-derived growth factor BB. At the cellular and molecular levels, we found that 18β-GA could significantly reduce the accumulation of misfolded protein in rat lung tissue, inhibit ERS activation, reduce the expression of GRP78, p-PERK, p-eIF2α, and p-NF-κB p65, and increase IκB protein expression. 18β-GA could inhibit the migration of NF-κB into the nucleus, reduce the contents of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and monocyte chemoattractant protein-1 (MCP-1) in the culture supernatant of HPASMCs, and reduce GRP78, p-PERK, p-eIF2α, p-NF-κB p65, TNF-α, IL-6, and MCP-1 protein expression, increase IκB protein expression in HPASMCs. According to what we observed, this study indicated that 18β-GA could treat PAH, which is related to the inhibition of PERK/eIF2α/NF-κB signaling pathway.

Pulmonary health effects of wintertime particulate matter from California and China following repeated exposure and cessation

Epidemiological studies show strong associations between fine particulate matter (PM2.5) air pollution and adverse pulmonary effects. In the present study, wintertime PM2.5 samples were collected from three geographically similar regions—Sacramento, California, USA; Jinan, Shandong, China; and Taiyuan, Shanxi, China—and extracted to form PMCA, PMSD, and PMSX, respectively, for comparison in a BALB/c mouse model. Each of four groups was oropharyngeally administered Milli-Q water vehicle control (50 μL) or one type of PM extract (20 μg/50 μL) five times over two weeks. Mice were necropsied on post-exposure days 1, 2, and 4 and examined using bronchoalveolar lavage (BAL), histopathology, and assessments of cytokine/chemokine mRNA and protein expression. Chemical analysis demonstrated all three extracts contained black carbon, but PMSX contained more sulfates and polycyclic aromatic hydrocarbons (PAHs) associated with significantly greater neutrophil numbers and greater alveolar/bronchiolar inflammation on post-exposure days 1 and 4. On day 4, PMSX-exposed mice also exhibited significant increases in interleukin-1 beta, tumor necrosis factor-alpha, and chemokine C-X-C motif ligands-3 and -5 mRNA, and monocyte chemoattractant protein-1 protein. These combined findings suggest greater sulfate and PAH content contributed to a more intense and progressive inflammatory response with repeated PMSX compared to PMCA or PMSD exposure.

Interleukin-6 via Toll-Like Receptor 3 Signaling Attenuates the Expression of Proinflammatory Chemokines in Human Podocytes

Background: Although toll-like receptor 3 (TLR3) signaling is involved in the development of certain chronic kidney diseases, the specific molecular mechanisms underlying inflammatory reactions via activation of TLR3 signaling in human podocytes remain unclear. Interleukin (IL)-6 is a pleiotropic cytokine associated with innate and adaptive immune responses; however, little is known about the implication of IL-6 via the activation of regional TLR3 signaling in the inflammatory reactions in human podocytes. Methods: We treated immortalized human podocytes with polyinosinic-polycytidylic acid (poly IC), an authentic viral double-stranded RNA, and assessed the expression of IL-6, monocyte chemoattractant protein-1 (MCP-1), and C-C motif chemokine ligand 5 (CCL5) using quantitative real-time reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. To further elucidate the poly IC-induced signaling pathway, we subjected the cells to RNA interference against IFN-β and IL-6. Results: We found that the activation of TLR3 induced expression of IL-6, MCP-1, CCL5, and IFN-β in human podocytes. RNA interference experiments revealed that IFN-β was involved in the poly IC-induced expression of IL-6, MCP-1, and CCL5. Interestingly, IL-6 knockdown markedly increased the poly IC-induced expression of MCP-1 and CCL5. Further, treatment of cells with IL-6 attenuated the expression of CCL5 and MCP-1 mRNA and proteins. Conclusion: IL-6 induced by TLR3 signaling negatively regulates the expression of representative TLR3 signaling-dependent proinflammatory chemokines in human podocytes.

Enhancement of Porphyromonas gingivalis-Lipopolysaccharide Induced MCP-1 Expression by High Glucose in Human Endothelial Cells

To investigate the synergistic effects of periodontal disease and diabetes mellitus on atherosclerosis, we evaluated the monocyte chemoattractant protein-1 (MCP-1) expression of endothelial cells induced by Porphyromonas gingivalis-lipopolysaccharide (LPS) and high glucose. We also tested whether antioxidants could inhibit the MCP-1 expression induced by the simultaneous stimulation of LPS and high glucose. Human umbilical vein endothelial cells (HUVECs) were stimulated with various concentrations of P. gingivalis-LPS (0.1, 1.0, and 10 µg/mL) in normal glucose (5.5 mM), with high glucose (10 mM and 20 mM), and with 0.1 µg/mL P. gingivalis-LPS in high glucose. MCP-1 expressions were measured by realtime RT-PCR and ELISA. Vitamin C (100 µM) and vitamin E (50 µM) were administered before simultaneous stimulation with 0.1 µg/mL P. gingivalis-LPS and 20 mM glucose. LPS ≥ 1.0 μg/mL increased the expression of MCP-1 mRNA and protein compared to unstimulated HUVECs. High glucose in the culture medium increased the MCP-1 mRNA expression slightly but significantly at 2 hr of incubation, but the MCP-1 protein level was not increased. Simultaneous stimulation with 0.1 μg/mL LPS and high glucose increased the expression of MCP-1 mRNA and protein compared to unstimulated HUVECs. By contrast, pre-incubation of vitamin C or E inhibited the increase of MCP-1 mRNA expression induced by 0.1 μg/mL LPS and 20 mM glucose. Our finding that high glucose enhanced the MCP-1 expression with even a low level of LPS suggests that caution is advisable regarding the atherogenicity of diabetic patients with periodontal disease.

Cerebrospinal fluid monocyte chemoattractant protein 1 correlates with progression of Parkinson\u2019s disease

Parkinson’s disease (PD) and multiple system atrophy (MSA) have overlapping symptoms, challenging a correct early diagnosis. Prognostic information is needed to predict disease progression and provide appropriate counseling. Neuroinflammation plays a role in the pathology of both disorders, as shown in genetic and postmortem tissue studies. Monocyte chemoattractant protein 1 (MCP-1) and neuroleukin (NLK) are two inflammatory proteins with potential to serve as biomarkers of the neuroinflammatory process. Here, we aimed to study the biomarker potential of both MCP-1 and NLK protein levels in cerebrospinal fluid (CSF) from a longitudinal cohort study (Radboudumc, Nijmegen, The Netherlands), consisting of PD patients (n = 46), MSA patients (n = 17) and control subjects (n = 52) using ELISA. We also correlated MCP-1 and NLK levels in CSF to several parameters of disease. We showed that MCP-1 levels in CSF positively correlate with PD progression (ρ = 0.363; p = 0.017) but could not differentiate between PD, MSA, and controls. NLK levels in CSF neither differentiated between PD, MSA, and controls, nor correlated with disease progression. Our results indicate that MCP-1 levels in CSF cannot distinguish between PD, MSA, and controls but correlate with disease progression in PD patients, suggesting that neuroinflammation is associated with clinical progression in PD. The correlation with disease progression was only moderate, so MCP-1 levels in CSF should be included in a larger battery of prognostic biomarkers that also tackle different pathophysiological processes.

Sirt1 suppresses MCP-1 production during the intervertebral disc degeneration by inactivating AP-1 subunits c-Fos/c-Jun.

The anti-inflammatory effect of Sirtuin 1 (Sirt1) during intervertebral disc degeneration (IDD) has been widely confirmed. Monocyte chemoattractant protein-1 (MCP-1) activation is the initiating inflammatory response associated with the IDD. However, whether Sirt1 suppresses MCP-1 in the intervertebral disc is unclear. The MCP-1 and Sirt1 protein expression in the degenerated and non-degenerated NP tissues were compared by immunohistochemistry (IHC). We induced nucleus pulposus (NP) cell degeneration by IL-1β and mediated cellular Sirt1 expression through the Sirt1 activator resveratrol (Res) or inhibitor Nicotinamide (Nico). In addition, the inhibitors of MCP-1 and Activator protein 1 (AP-1) were also used in cell culture. The function of NP cells was determined by the type II collagen and Cell Counting Kit-8 (CCK-8) assay. We assessed the Sirt1 and MCP-1 expression by the Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR). The AP-1 activity was valued by the phosphorylation of its components c-Fos, and c-Jun. Both in vivo and in vitro experimental results indicated that MCP-1 was upregulated in the degenerated condition, which was opposite to Sirt1 expression. Res suppressed AP-1, the phosphorylation of c-Fos/c-Jun, and the MCP-1 expression. On the contrary, Sirt1 downregulation by Nico aggravated the phosphorylation of c-Fos/c-Jun and MCP-1 expression. However, the MCP-1 suppression did not affect the Sirt1 and AP-1 levels. The destruction of AP-1 activation also inhibited MCP-1 expression but not Sirt1. The upregulation of Sirt1 and suppression of MCP-1 improved the type II collagen expression and cell viability, which was injured by IL-1β. Sirt1 suppresses the MCP-1 production in the degenerated NP cells by suppressing the phosphorylation of the AP-1 subunits c-Fos and c-Jun.

β-Aminoisobutyric Acid Suppresses Atherosclerosis in Apolipoprotein E-Knockout Mice

Endurance exercise training has been shown to induce peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) expression in skeletal muscle. We recently reported that skeletal muscle-specific PGC-1α overexpression suppressed atherosclerosis in apolipoprotein E-knockout (ApoE-/-) mice. β-Aminoisobutyric acid (BAIBA) is a PGC-1α-dependent myokine secreted from myocytes that affects multiple organs. We have also reported that BAIBA suppresses tumor necrosis factor-alpha-induced vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) gene expression in endothelial cells. In the present study, we hypothesized that BAIBA suppresses atherosclerosis progression, and tested that hypothesis with ApoE-/- mice. The mice were administered water containing BAIBA for 14 weeks, and were then sacrificed at 20 weeks of age. Atherosclerotic plaque area, plasma BAIBA concentration, and plasma lipoprotein profiles were assessed. Immunohistochemical analyses of the plaque were performed to assess VCAM-1 and MCP-1 protein expression levels and macrophage infiltration. The results showed that BAIBA administration decreased atherosclerosis plaque area by 30%, concomitant with the elevation of plasma BAIBA levels. On the other hand, plasma lipoprotein profiles were not changed by the administration. Immunohistochemical analyses indicated reductions in VCAM-1, MCP-1, and Mac-2 protein expression levels in the plaque. These results suggest that BAIBA administration suppresses atherosclerosis progression without changing plasma lipoprotein profiles. We propose that the mechanisms of this suppression are reductions in both VCAM-1 and MCP-1 expression as well as macrophage infiltration into the plaque.