The zinc finger transcription factor, KLF2, protects against COVID-19 associated endothelial dysfunction

Coronavirus disease 2019 (COVID-19) is regarded as an endothelial disease (endothelialitis) with its patho-mechanism being incompletely understood. Emerging evidence has demonstrated that endothelial dysfunction precipitates COVID-19 and its accompanying multi-organ injuries. Thus, pharmacotherapies targeting endothelial dysfunction have potential to ameliorate COVID-19 and its cardiovascular complications. The objective of the present study is to evaluate whether kruppel-like factor 2 (KLF2), a master regulator of vascular homeostasis, represents a therapeutic target for COVID-19-induced endothelial dysfunction. Here, we demonstrate that the expression of KLF2 was reduced and monocyte adhesion was increased in endothelial cells treated with COVID-19 patient serum due to elevated levels of pro-adhesive molecules, ICAM1 and VCAM1. IL-1β and TNF-α, two cytokines elevated in cytokine release syndrome in COVID-19 patients, decreased KLF2 gene expression. Pharmacologic (atorvastatin and tannic acid) and genetic (adenoviral overexpression) approaches to augment KLF2 levels attenuated COVID-19-serum-induced increase in endothelial inflammation and monocyte adhesion. Next-generation RNA-sequencing data showed that atorvastatin treatment leads to a cardiovascular protective transcriptome associated with improved endothelial function (vasodilation, anti-inflammation, antioxidant status, anti-thrombosis/-coagulation, anti-fibrosis, and reduced angiogenesis). Finally, knockdown of KLF2 partially reversed the ameliorative effect of atorvastatin on COVID-19-serum-induced endothelial inflammation and monocyte adhesion. Collectively, the present study implicates loss of KLF2 as an important molecular event in the development of COVID-19-induced vascular disease and suggests that efforts to augment KLF2 levels may be therapeutically beneficial.

Peucedanum ostruthium Inhibits E-Selectin and VCAM-1 Expression in Endothelial Cells through Interference with NF-κB Signaling

Twenty natural remedies traditionally used against different inflammatory diseases were probed for their potential to suppress the expression of the inflammatory markers E-selectin and VCAM-1 in a model system of IL-1 stimulated human umbilical vein endothelial cells (HUVEC). One third of the tested extracts showed in vitro inhibitory effects comparable to the positive control oxozeaenol, an inhibitor of TAK1. Among them, the extract derived from the roots and rhizomes of Peucedanum ostruthium (i.e., Radix Imperatoriae), also known as masterwort, showed a pronounced and dose-dependent inhibitory effect. Reporter gene analysis demonstrated that inhibition takes place on the transcriptional level and involves the transcription factor NF-κB. A more detailed analysis revealed that the P. ostruthium extract (PO) affected the phosphorylation, degradation, and resynthesis of IκBα, the activation of IKKs, and the nuclear translocation of the NF-κB subunit RelA. Strikingly, early effects on this pathway were less affected as compared to later ones, suggesting that PO may act on mechanism(s) that are downstream of nuclear translocation. As the majority of cognate NF-κB inhibitors affect upstream events such as IKK2, these findings could indicate the existence of targetable signaling events at later stages of NF-κB activation.

Mitochondrial Fission Mediates Endothelial Inflammation

Endothelial inflammation and mitochondrial dysfunction have been implicated in cardiovascular diseases, yet, a unifying mechanism tying them together remains limited. Mitochondrial dysfunction is frequently associated with mitochondrial fission/fragmentation mediated by the GTPase Drp1 (dynamin-related protein 1). Nuclear factor (NF)-κB, a master regulator of inflammation, is implicated in endothelial dysfunction and resultant complications. Here, we explore a causal relationship between mitochondrial fission and NF-κB activation in endothelial inflammatory responses. In cultured endothelial cells, TNF-α (tumor necrosis factor-α) or lipopolysaccharide induces mitochondrial fragmentation. Inhibition of Drp1 activity or expression suppresses mitochondrial fission, NF-κB activation, vascular cell adhesion molecule-1 induction, and leukocyte adhesion induced by these proinflammatory factors. Moreover, attenuations of inflammatory leukocyte adhesion were observed in Drp1 heterodeficient mice as well as endothelial Drp1 silenced mice. Intriguingly, inhibition of the canonical NF-κB signaling suppresses endothelial mitochondrial fission. Mechanistically, NF-κB p65/RelA seems to mediate inflammatory mitochondrial fission in endothelial cells. In addition, the classical anti-inflammatory drug, salicylate, seems to maintain mitochondrial fission/fusion balance against TNF-α via inhibition of NF-κB. In conclusion, our results suggest a previously unknown mechanism whereby the canonical NF-κB cascade and a mitochondrial fission pathway interdependently regulate endothelial inflammation.

Mevastatin-Induced AP-1-Dependent HO-1 Expression Suppresses Vascular Cell Adhesion Molecule-1 Expression and Monocyte Adhesion on Human Pulmonary Alveolar Epithelial Cells Challenged with TNF-α

Mevastatin (MVS) has been previously shown to induce heme oxygenase (HO)-1 expression through Nox/ROS-dependent PDGFRα/PI3K/Akt/Nrf2/ARE axis in human pulmonary alveolar epithelial cells (HPAEpiCs). However, alternative signaling pathways might involve in MVS-induced HO-1 expression. We found that tumor necrosis factor α (TNFα) induced vascular cell adhesion protein 1 (VCAM-1) expression and NF-κB p65 phosphorylation which were attenuated by pretreatment with MVS via up-regulation of HO-1, determined by Western blot and real-time qPCR. TNFα-induced VCAM-1 expression was attenuated by an NF-κB inhibitor, Bay117082. The inhibitory effects of MVS were reversed by tin protoporphyrin (SnPP)IX (an inhibitor of HO-1 activity). In addition, pretreatment with the inhibitor of pan-Protein kinase C (PKC) (GF109203X), PKCα (Gö6983), Pyk2 (PF431396), p38α MAPK (SB202190), JNK1/2 (SP600125), or AP-1 (Tanshinone IIA), and transfection with their respective siRNAs abolished MVS-induced HO-1 expression in HPAEpiCs. c-Jun (one of AP-1 subunits) was activated by PKCα, Pyk2, p38α MAPK, and JNK1/2, which turned on the transcription of the homx1 gene. The interaction between c-Jun and HO-1 promoter was confirmed by a chromatin immunoprecipitation (ChIP) assay, which was attenuated by these pharmacological inhibitors. These results suggested that MVS induces AP-1/HO-1 expression via PKCα/Pyk2/p38α MAPK- or JNK1/2-dependent c-Jun activation, which further binds with AP-1-binding site on HO-1 promoter and suppresses the TNFα-mediated inflammatory responses in HPAEpiCs. Thus, upregulation of the AP-1/HO-1 system by MVS exerts a potentially therapeutic strategy to protect against pulmonary inflammation.

The Roles of Lipoprotein in Psoriasis

The association between psoriasis and cardiovascular disease risk has been supported by recent epidemiological data. Patients with psoriasis have an increased adjusted relative risk for myocardial infarction. As such, the cardiovascular risk conferred by severe psoriasis may be comparable to what is seen with other well-established risk factors, such as diabetes mellitus. Previous studies demonstrated that low-density lipoprotein (LDL) plays critical roles during atherogenesis. It may be caused by the accumulation of macrophages and lipoprotein in the vessel wall. Oxidized LDL (ox-LDL) stimulates the expression of adhesion molecules, such as ICAM-1 and VCAM-1, on endothelial cells and increases the attachment of mononuclear cells and the endothelium. Even though previous evidence demonstrated that psoriasis patients have tortuous and dilated blood vessels in the dermis, which results in the leakage of ox-LDL, the leaked ox-LDL may increase the expression of adhesion molecules and cytokines, and disturb the static balance of osmosis. Therefore, exploration of the relationship between hyperlipidemia and psoriasis may be another novel treatment option for psoriasis and may represent the most promising strategy.

Antiinflammatory activity of astragaloside IV is mediated by inhibition of NF-κB activation and adhesion molecule expression

The regulated expression of adhesion molecules on the surface of endothelial cells is a key process in the pathogenesis of inflammation. The saponin astragaloside IV (AS-IV), a 3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosylcycloastragenol purified from the Chinese medical herb Astragalus membranaceus(Fisch) Bge.has been shown to have anti-inflammatory effects in vivo.In this study we have investigated the effect of AS-IV on cytokine-and LPS-stimulated expression of adhesion molecules in and leukocyte adhesion to endothelial cells. We have demonstrated that AS-IV significantly reduced the adhesion promoting activity of LPS-stimulated HUVECs for polymorph-nuclear leukocytes (PMNs) and the monocytic cell line THP-1. Furthermore, by using specific cell ELISAs we could show that AS-IV decreased the LPS-induced expression of E-selectin and VCAM-1 on the surface of HUVECs in a dose and time dependent manner, whereas the expression of ICAM-1 was not affected by AS-IV. AS-IV also inhibits TNFβ-induced VCAM-1 expression. The saponin octyl-D-glucopyranoside had no effect on the LPS-induced expression of E-selectin and VCAM-1 excluding an unspecific detergent-like effect of AS-IV. Moreover, AS-IV significantly inhibited LPS- and TNFβ-induced specific mRNA levels for E-selectin and VCAM-1. Finally, we could show that AS-IV completely abolished LPS- and TNFα-induced nuclear translocation of NF-κB and NF-κB DNA binding activity in endothelial cells. We conclude that the ability of AS-IV to inhibit the NF-κB pathway might be one underlying mechanism contributing to its anti-inflammatory potential in vivo.

NFκB transcription factor (p65) immunohistochemistry in leprosy dermal microvasculature

Leprosy caused by Mycobacterium leprae is characterized by a spectrum of clinical manifestations that are determined by the predominant immunological profile of the host. The recruitment of leukocytes to the sites of injury can influence the development of these profiles. Cell adhesion molecules such as ICAM-1, VCAM-1 and CD62E participate in this process and their expression is regulated by transcriptions factors such as NFκB. To correlate the expression of cell adhesion molecules and NFκB (p65) in leprosy lesions, 30 skin biopsies of patients with leprosy [16 with the tuberculoid (TT) or borderline tuberculoid (BT) forms and 14 with the lepromatous (LL) or borderline lepromatous (BL) forms] were analyzed by immunohistochemistry. A larger mean number of cells expressing VCAM-1 (BT/TT: 18.28 ± 1.4; BL/LL: 10.67 ± 1.2; p = 0.0002), ICAM-1 (BT/TT: 9.92 ± 1.1; BL/LL: 5.87 ± 1.0; p = 0.0084) and CD62E (BT/TT: 13.0 ± 1.5; BL/LL: 2.58 ± 0.3; p = 0.0001) were observed in BT and TT lesions. The mean number of cells expressing NFκB was similar in the two clinical forms (BT/TT: 2.21 ± 2.7; BL/LL: 2.35 ± 3.1;p = 0.9285). No significant correlation was observed between expression of the transcription factor and adhesion molecules analyzed. The synthesis of ICAM-1, VCAM-1 and CD62E depends on the activation of NFκB, which acts synergistically with other transcription factors. Adequate activation of intracellular signaling pathways results in the production of endothelial adhesion molecules, contributing to the recruitment of cells to the site of injury and thus eliciting an effective inflammatory response in the elimination of the bacillus.

Prenylated Polyphenols from Clusiaceae and Calophyllaceae with Immunomodulatory Activity on Endothelial Cells

Endothelial cells (ECs) are key players in inflammation and immune responses involved in numerous pathologies. Although attempts were experimentally undertaken to prevent and control EC activation, drug leads and probes still remain necessary. Natural products (NPs) from Clusiaceous and Calophyllaceous plants were previously reported as potential candidates to prevent endothelial dysfunction. The present study aimed to identify more precisely the molecular scaffolds that could limit EC activation. Here, 13 polyphenols belonging to 5 different chemical types of secondary metabolites (i.e., mammea coumarins, a biflavonoid, a pyranochromanone acid, a polyprenylated polycyclic acylphloroglucinol (PPAP) and two xanthones) were tested on resting and cytokine-activated EC cultures. Quantitative and qualitative changes in the expression of both adhesion molecules (VCAM-1, ICAM-1, E-selectin) and major histocompatibility complex (MHC) molecules have been used to measure their pharmaceutical potential. As a result, we identified 3 mammea coumarins that efficiently reduce (up to >90% at 10 μM) both basal and cytokine-regulated levels of MHC class I, class II, MICA and HLA-E on EC surface. They also prevented VCAM-1 induction upon inflammation. From a structural point of view, our results associate the loss of the free prenyl group substituting mammea coumarins with a reduced cellular cytotoxicity but also an abrogation of their anti-inflammatory potential and a reduction of their immunosuppressive effects. A PPAP, guttiferone J, also triggers a strong immunomodulation but restricted to HLA-E and MHC class II molecules. In conclusion, mammea coumarins with a free prenyl group and the PPAP guttiferone J emerge as NPs able to drastically decrease both VCAM-1 and a set of MHC molecules and to potentially reduce the immunogenicity of the endothelium.

Absence of In Vivo Generalized Pro-Inflammatory Endothelial Activation in Severe, Early-Onset Preeclampsia

OBJECTIVE

At present it is unclear whether endothelial activation is systematically present in preeclampsia or restricted to specialized vascular beds. Therefore, this study aimed to investigate the presence of generalized proinflammatory endothelial activation in severe, early-onset preeclampsia in vivo.

METHODS

During caesarean section, biopsies were obtained from abdominal subcutaneous fat, abdominal fascia, and myometrium from 11 severe, early-onset preeclamptic and 19 healthy pregnant women. Prior to caesarean, section plasma levels of von Willebrand Factor (vWF), sVCAM-1, and C-reactive protein (CRP) were measured by ELISA. Consecutive cryostat sections were stained immunohistochemically for CD31, E-selectin, VCAM-1, and ICAM-1. For subcutaneous fat tissue, endothelial gene expression levels of E-selectin, VCAM-1, ICAM-1, endothelin-1 (ET-1), and endothelial nitric oxide synthase (eNOS) were quantified by real-time RT-PCR, using normalization to the endothelium-specific housekeeping genes CD31 and VE-cadherin.

RESULTS

Plasma levels of vWF, sVCAM-1, and CRP were elevated in the preeclampsia group compared to the control group, indicating enhanced endothelial activation and inflammatory response in the severely diseased preeclamptic women. By immunohistochemical analysis, no E-selectin and VCAM-1 expression could be detected in, and no differences in endothelial ICAM-1 staining could be observed between the preeclampsia and the control group for all tissues studied. Endothelial gene expression levels of E-selectin, VCAM-1, ICAM-1, ET-1, and eNOS were comparable between the preeclampsia and control group.

CONCLUSION

Protein and gene expression analysis of E-selectin, VCAM-1, ICAM-1, ET-1, and eNOS, key mediators involved in pro-inflammatory endothelial activation, could not identify endothelial activation in severe, early-onset preeclampsia in the tissues studied. However, elevated plasma levels of markers of endothelial activation and inflammation were observed. These results may suggest that in severe, early-onset preeclampsia pro-inflammatory endothelial cell activation is not a generalized phenomenon, but is likely restricted to (possibly organ-specific) specialized vascular beds.

Plasma Factors in Severe Early-Onset Preeclampsia Do Not Substantially Alter Endothelial Gene Expression In Vitro

OBJECTIVE

Systemic endothelial dysfunction is a central feature in the pathophysiology of preeclampsia. Its cell biologic and molecular basis is poorly understood. One leading hypothesis argues that endothelial dysfunction is caused by (at present largely unknown) circulating factors released from the ischemic placenta. This study investigated the effects of plasma factors of severe, early-onset preeclamptic women versus healthy pregnant women on endothelial gene expression in vitro.

METHODS

Plasma samples were taken from eight severe early-onset preeclamptic women and eight matched pregnant control women. Primary human umbilical vein endothelial cell (HUVEC) and human glomerular microvascular endothelial cell (hGMEC) cultures were incubated with 20% (vol/vol) plasma for 4, 12, and 24 hours. Identical amounts of RNA isolated from HUVEC from three preeclamptic and three control samples were pooled for each time point, and subsequently hybridized on human 60-mer oligonucleotide microarrays containing 17,000 genes. Gene expression levels of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), interleukin-8 (IL-8), and interleukin-6 (IL-6) in HUVEC and hGMEC were quantified using real-time reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

Microarray analyses of individual genes identified no genes that were up- or down-regulated more than 2.7-fold, and analyses of gene ontologies showed no gene ontology significantly up- or down-regulated in HUVEC by preeclamptic plasma. IL-8 gene expression was modestly induced by preeclamptic plasma after 4, 12, and 24 hours of HUVEC and hGMEC incubation, as identified by real-time RT-PCR. The other genes analyzed did not show altered regulation by preeclamptic plasma factors.

CONCLUSIONS

In vitro, plasma from preeclamptic patients does not substantially alter endothelial gene expression profile. Only modest induction of IL-8 gene expression was observed. These results indicate that mechanisms other than soluble plasma constituents are likely involved in systemic endothelial cell activation in preeclampsia.

The Prominent Role of P38 Mitogen-Activated Protein Kinase in Insulin-Mediated Enhancement of VCAM-1 Expression in Endothelial Cells

Insulin levels are a marker for cardiovascular events, but the link between hyperinsulinemia and atherosclerosis is poorly understood. We previously showed that insulin increases monocyte-endothelial interactions and the endothelial expression of the pro-atherogenic vascular cell adhesion molecule-1 (VCAM-1). The aim of this study is to examine molecular mechanisms involved in the effect of insulin on VCAM-1 expression. Human umbilical vein endothelial cells (HUVEC) were incubated with insulin (0–24 h) ± inhibitors of signaling pathways potentially involved. At pathophysiological concentrations (10−9-10−7 M), insulin selectively induced VCAM-1 expression. The p38mitogen activated protein(MAP) kinase inhibitors SB203580 and SB202190, and partially the c-Jun NH2-terminal kinase (JNK) inhibitor SP600127, decreased insulin effect on VCAM-1. Gene silencing by small interfering RNA significantly reduced the expression of p38MAP kinase, and this was accompanied by suppression of insulin-stimulated VCAM-1 expression. Treatment with insulin also led to the activation of NF-κB and induction of IκB-α phosphorylation, thus accounting for NF-κB translocation into the nucleus. Co-treatment of HUVEC with insulin and SB202190 strongly reverted the stimulatory effect of insulin on NF-κB activation, thus establishing a link between NF-κB activation and p38MAPkinase-mediated induction of VCAM-1 by insulin. In conclusion, pathophysiological insulin concentrations increase VCAM-1 expression and activate NF-κB. This mostly occurs through stimulation of p38MAP kinase.

Early High-dosage Atorvastatin Treatment Improved Serum Immune-inflammatory Markers and Functional Outcome in Acute Ischemic Strokes Classified as Large Artery Atherosclerotic Stroke: A Randomized Trial

Statins have beneficial effects on cerebral circulation and brain parenchyma during ischemic stroke and reperfusion. The primary hypothesis of this randomized parallel trial was that treatment with 80 mg/day of atorvastatin administered early at admission after acute atherosclerotic ischemic stroke could reduce serum levels of markers of immune-inflammatory activation of the acute phase and that this immune-inflammatory modulation could have a possible effect on prognosis of ischemic stroke evaluated by some outcome indicators. We enrolled 42 patients with acute ischemic stroke classified as large arteries atherosclerosis stroke (LAAS) randomly assigned in a randomized parallel trial to the following groups: Group A, 22 patients treated with atorvastatin 80 mg (once-daily) from admission day until discharge; Group B, 20 patients not treated with atorvastatin 80 mg until discharge, and after discharge, treatment with atorvastatin has been started. At 72 hours and at 7 days after acute ischemic stroke, subjects of group A showed significantly lower plasma levels of tumor necrosis factor-α, interleukin (IL)-6, vascular cell adhesion molecule-1, whereas no significant difference with regard to plasma levels of IL-10, E-Selectin, and P-Selectin was observed between the 2 groups. At 72 hours and 7 days after admission, stroke patients treated with atorvastatin 80 mg in comparison with stroke subjects not treated with atorvastatin showed a significantly lower mean National Institutes of Health Stroke Scale and modified Rankin scores. Our findings provide the first evidence that atorvastatin acutely administered immediately after an atherosclerotic ischemic stroke exerts a lowering effect on immune-inflammatory activation of the acute phase of stroke and that its early use is associated to a better functional and prognostic profile.

Myocardial Structural and Biological Anomalies Induced by High Fat Diet in Psammomys obesus Gerbils

Background

Psammomys obesus gerbils are particularly prone to develop diabetes and obesity after brief period of abundant food intake. A hypercaloric high fat diet has been shown to affect cardiac function. Here, we sought to determine whether a short period of high fat feeding might alter myocardial structure and expression of calcium handling proteins in this particular strain of gerbils.

Methods

Twenty Psammomys obesus gerbils were randomly assigned to receive a normal plant diet (controls) or a high fat diet. At baseline and 16-week later, body weight, plasma biochemical parameters (including lipid and carbohydrate levels) were evaluated. Myocardial samples were collected for pathobiological evaluation.

Results

Sixteen-week high fat dieting resulted in body weight gain and hyperlipidemia, while levels of carbohydrates remained unchanged. At myocardial level, high fat diet induced structural disorganization, including cardiomyocyte hypertrophy, lipid accumulation, interstitial and perivascular fibrosis and increased number of infiltrating neutrophils. Myocardial expressions of pro-apoptotic Bax-to-Bcl-2 ratio, pro-inflammatory cytokines [interleukin (IL)-1β and tumor necrosis factor (TNF)-α], intercellular (ICAM1) and vascular adhesion molecules (VCAM1) increased, while gene encoding cardiac muscle protein, the alpha myosin heavy polypeptide (MYH6), was downregulated. Myocardial expressions of sarco(endo)plasmic calcium-ATPase (SERCA2) and voltage-dependent calcium channel (Cacna1c) decreased, while protein kinase A (PKA) and calcium-calmodulin-dependent protein kinase (CaMK2D) expressions increased. Myocardial expressions of ryanodine receptor, phospholamban and sodium/calcium exchanger (Slc8a1) did not change.

Conclusions

We conclude that a relative short period of high fat diet in Psammomys obesus results in severe alterations of cardiac structure, activation of inflammatory and apoptotic processes, and altered expression of calcium-cycling determinants.

Rutin improves endotoxin-induced acute lung injury via inhibition of iNOS and VCAM-1 expression

Endotoxins exist anywhere including in water pools, dust, humidifier systems, and machining fluids. The major causal factor is endotoxins in many serious diseases, such as fever, sepsis, multi-organ failure, meningococcemia, and severe morbidities like neurologic disability, or hearing loss. Endotoxins are also called lipopolysaccharide (LPS) and are important pathogens of acute lung injury (ALI). Rutin has potential beneficial effects including anti-inflammation, antioxidation, anti-hyperlipidemia, and anti-platelet aggregation. Pre-treatment with rutin inhibited LPS-induced neutrophil infiltration in the lungs. LPS-induced expression of vascular cell adhesion molecule (VCAM)-1 and inducible nitric oxide synthase (iNOS) was suppressed by rutin, but there was no influence on expression of intercellular adhesion molecule-1 and cyclooxygenase-2. In addition, activation of the nuclear factor (NF)κB was reduced by rutin. Furthermore, we found that the inhibitory concentration of rutin on expression of VCAM-1 and iNOS was similar to NFκB activation. In conclusion, rutin is a potential protective agent for ALI via inhibition of neutrophil infiltration, expression of VCAM-1 and iNOS, and NFκB activation.

[IMPACT OF ACTIVE OXYGEN FORMS INDUCTION ON EXPRESSION OF MOLECULAR ADHESION AND PARACRINE ACTIVITY OF MESENCHIMAL STROMAL CELLS]

Impact of low doses of active oxygen forms (AOFs) on the paracrine activity of mesenchimal stromal cells (MSCs) was studied. Photodynamic treatment (PDT) was shown to be a method for controlled generation of intracellular AOFs. Active oxygen forms generated at a dose of 0.25J/cm² do not impact significantly the MSCs mitochondrial activity or viability and can be recognized as regulatory. This was the first discovery that low-intensity PDT modulates substantially the MSCs paracrine activity which was manifested by an increased secretion of proinflammatory cytokines (IL-6, IL-8), vascular endothelium growth factor (VEGF), and suppressed secretion of the transforming growth factor (TGFβ). While expression of intercellular adhesion molecule ICAM-1 increases and of Thy-1 antigen (a common MSCs marker) decreases, no changes occur to expression of chemokine receptor CXCR4 or other adhesion molecules (H-CAM, MCAM and VCAM-1). Our data make it clear that low-dose PDT is the most important regulator of the MSCs function. Key words: active oxygen forms, mesenchimal stromal cells, paracrine activity, photodynamic exposure.

Heme Oxygenase-1 Inhibits HLA Class I Antibody-Dependent Endothelial Cell Activation

Antibody-mediated rejection (AMR) is a key limiting factor for long-term graft survival in solid organ transplantation. Human leukocyte antigen (HLA) class I (HLA I) antibodies (Abs) play a major role in the pathogenesis of AMR via their interactions with HLA molecules on vascular endothelial cells (ECs). The antioxidant enzyme heme oxygenase (HO)-1 has anti-inflammatory functions in the endothelium. As complement-independent effects of HLA I Abs can activate ECs, it was the goal of the current study to investigate the role of HO-1 on activation of human ECs by HLA I Abs. In cell cultures of various primary human macro- and microvascular ECs treatment with monoclonal pan- and allele-specific HLA I Abs up-regulated the expression of inducible proinflammatory adhesion molecules and chemokines (vascular cell adhesion molecule-1 [VCAM-1], intercellular cell adhesion molecule-1 [ICAM-1], interleukin-8 [IL-8] and monocyte chemotactic protein 1 [MCP-1]). Pharmacological induction of HO-1 with cobalt-protoporphyrin IX reduced, whereas inhibition of HO-1 with either zinc-protoporphyrin IX or siRNA-mediated knockdown increased HLA I Ab-dependent up-regulation of VCAM-1. Treatment with two carbon monoxide (CO)-releasing molecules, which liberate the gaseous HO product CO, blocked HLA I Ab-dependent EC activation. Finally, in an in vitro adhesion assay exposure of ECs to HLA I Abs led to increased monocyte binding, which was counteracted by up-regulation of HO-1. In conclusion, HLA I Ab-dependent EC activation is modulated by endothelial HO-1 and targeted induction of this enzyme may be a novel therapeutic approach for the treatment of AMR in solid organ transplantation.

CD4+CD29+T cells are blamed for the persistent inflammatory response in ulcerative colitis

Ulcerative colitis (UC) is a chronic gastrointestinal disorder eliciting occurrence of colorectal cancer, the third most common human malignancy. The diagnosis of UC is based on clinical symptoms combined with typical findings on endoscopy, radiology, and ultimately pathology. We investigated the variation trend of CD4+CD29+T cells together with MPO, VCAM-1 in different periods of rat UC model and UC patients. We also evaluated the relationship between CD4+CD29+T cells and disease severity. UC model was induced by administering DNCB liquid and acetate solution. We found upregulated expression of CD4+CD29+T cells in both peripheral blood and colon from rats, and a similar trend for MPO and VCAM-1 in colon (P<0.05); the expression was especially enhanced in UC rats at two weeks after the model was established (P<0.01). Such upregulation was also indicated in active and remission UC patients as compared to the healthy and enteritis groups (P<0.05), with the highest expression level detected in the active UC patients (P<0.01). Pearson correlation analysis showed a positive correlation of CD4+CD29+T cells in rat and human peripheral blood with DAI score (rrat=0.712, rhuman=0.677, P<0.01), and MPO in colon (rrat=0.514, rhuman=0.682, P<0.05). These results suggest that CD4+CD29+T cells may act as major effector cell subsets in persistent inflammatory responses for UC and that infiltration into colon inflammation may be induced by the combination of VCAM-1 and CD29.

[Protective effects of antioxidants on chronic intermittent hypoxia-induced cardiac remodeling in mice]

OBJECTIVE

Chronic intermittent hypoxia (CIH) animal model was used to mimic the status of obstructive sleep apnea (OSA) in order to investigate the pathological mechanism of CIH-induced cardiac remodeling and observe the protective effect of antioxidants.

METHODS

FVB mice (8-10 weeks-old) were randomly divided into control (saline, i.p.) group and CIH group, reduced form of nicotinamide adenine dinucleotide phosphate oxidase inhibitor, apocynin (APO, 3 mg×kg(-1)×d(-1), i.p.) alone or CIH+APO, SOD mimic MnTMPyP (SODM, 5 mg×kg(-1)×d(-1), i.p.) alone or CIH+SODM (n = 5 each). After 4 weeks, cardiac function and structure were determined by echocardiography, cardiac inflammation, apoptosis, cardiac fibrosis and cardiac MDA contents were examined by Western blot and chemical-biological methods, respectively.

RESULTS

(1) Heart weight, LVIDd and LVIDs were increased while LVEF and FS were reduced in CIH group compared to control group (all P < 0.05). (2) Myocardial protein expression of ANP and VCAM-1 was significantly upregulated, myocardial MDA content and apoptosis as well as myocardial fibrosis marker CTGF and PAI-1 were increased in CIH group compared to control group (all P < 0.05). (3) Above parameters were similar between APO and CIH+APO as well as SODM and CIH+SODM (all P > 0.05).

CONCLUSION

CIH could induce cardiac remodeling and CIH-induced cardiac inflammation, cardiac oxidative injury, cardiac apoptosis and cardiac fibrosis serve as the pathological mechanisms of CIH-induced cardiac remodeling. The protective effects of the two antioxidants suggest that the main mechanism of CIH-induced cardiac injury is oxidative stress.

Ginsenoside Rg3 inhibits lipopolysaccharide-induced adhesion molecule expression in human umbilical vein endothelial cell and C57BL/6 mice

Intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), P- and E-selectin play a key role for initiation of vascular inflammation. Ginsenoside, a class of steroid glycosides, is abundant in Panax ginseng root, which has been used for health promotion in Korea. In this study, we investigated the mechanism by which ginsenoside Rg3 may inhibit ICAM-1 and VCAM-1 expressions stimulated with lipopolysaccharide (LPS) in human umbilical vein endothelial cell (HUVEC) and C57BL/6 mice. LPS increased ICAM-1 and VCAM-1 expression. Ginsenoside Rg3 prevented LPS-mediated increase of ICAM-1 and VCAM-1 expression. LPS induced IkappaBα (IκBα) degradation within 1 hr. Ginsenoside Rg3 prevented the IκBα degradation stimulated with LPS. Moreover, ginsenoside Rg3 reduced LPS-mediated THP-1 monocyte adhesion to HUVEC, in a concentration-dependent manner. In C57BL/6 mice, injection of LPS increased aortic ICAM-1 and VCAM-1 expression, which was prevented by ginsenoside Rg3. These data provide a novel mechanism where the ginsenoside Rg3 may provide direct vascular benefits with inhibition of leukocyte adhesion into vascular wall thereby providing prevention against vascular inflammatory disease.

Nicotine-induced ICAM-1 and VCAM-1 expression in mouse cardiac vascular endothelial cell via p38 MAPK signaling pathway

OBJECTIVE

To explore the link between cigarette smoking and thromboembolic events and to investigate cigarette smoking as a major risk factor in the etiology of atherosclerosis.

STUDY DESIGN

We determined the effect of nicotine on the expression of adhesion molecules, intercellular adhesion molecule (ICAM-1), and vascular cell adhesion molecule (VCAM-1) in mouse cardiac vascular endothelial cells and the involvement of important known intermediaries, namely p38 mitogen-activated protein kinase (MAPK) signaling pathway.

RESULTS

Our results indicate that nicotine can enhance the expression of ICAM-1 and VCAM-1 on mouse cardiac vascular endothelial cell via p38 MAPK signaling pathway, resulting in increased expression of the cellular adhesion molecules ICAM-1 and VCAM-1.

CONCLUSION

We demonstrate that 10(-6) M nicotine maximally enhances mouse cardiac vascular endothelial cell expression of ICAM-1 and VCAM-1 at 8 hours. Our results provide a putative mechanism by which nicotine stimulates expression of these adhesion molecules via p38 MAPK signaling pathway.

Carbon black nanoparticles promote endothelial activation and lipid accumulation in macrophages independently of intracellular ROS production

Exposure to nanoparticles (NPs) may cause vascular effects including endothelial dysfunction and foam cell formation, with oxidative stress and inflammation as supposed central mechanisms. We investigated oxidative stress, endothelial dysfunction and lipid accumulation caused by nano-sized carbon black (CB) exposure in cultured human umbilical vein endothelial cells (HUVECs), THP-1 (monocytes) and THP-1 derived macrophages (THP-1a). The proliferation of HUVECs or co-cultures of HUVECs and THP-1 cells were unaffected by CB exposure, whereas there was increased cytotoxicity, assessed by the LDH and WST-1 assays, especially in THP-1 and THP-1a cells. The CB exposure decreased the glutathione (GSH) content in THP-1 and THP-1a cells, whereas GSH was increased in HUVECs. The reactive oxygen species (ROS) production was increased in all cell types after CB exposure. A reduction of the intracellular GSH concentration by buthionine sulfoximine (BSO) pre-treatment further increased the CB-induced ROS production in THP-1 cells and HUVECs. The expression of adhesion molecules ICAM-1 and VCAM-1, but not adhesion of THP-1 to HUVECs or culture dishes, was elevated by CB exposure, whereas these effects were unaffected by BSO pre-treatment. qRT-PCR showed increased VCAM1 expression, but no change in GCLM and HMOX1 expression in CB-exposed HUVECs. Pre-exposure to CB induced lipid accumulation in THP-1a cells, which was not affected by the presence of the antioxidant N-acetylcysteine. In addition, the concentrations of CB to induce lipid accumulation were lower than the concentrations to promote intracellular ROS production in THP-1a cells. In conclusion, exposure to nano-sized CB induced endothelial dysfunction and foam cell formation, which was not dependent on intracellular ROS production.

Age-dependent modifications in vascular adhesion molecules and apoptosis after 48-h reperfusion in a rat global cerebral ischemia model

Stroke is one of the leading causes of death and permanent disability in the elderly. However, most of the experimental studies on stroke are based on young animals, and we hypothesised that age can substantially affect the stroke response. The two-vessel occlusion model of global ischemia by occluding the common carotid arteries for 15 min at 40 mmHg of blood pressure was carried out in 3- and 18-month-old male Sprague-Dawley rats. The adhesion molecules E- and P-selectin, cell adhesion molecules (CAMs), both intercellular (ICAM-1) and vascular (VCAM-1), as well as glial fibrillary acidic protein (GFAP), and cleaved caspase-3 were measured at 48 h after ischemia in the cerebral cortex and hippocampus using Western blot, qPCR and immunofluorescence techniques. Diametric expression of GFAP and a different morphological pattern of caspase-3 labelling, although no changes in the cell number, were observed in the neurons of young and old animals. Expression of E-selectin and CAMs was also modified in an age- and ischemia/reperfusion-dependent manner. The hippocampus and cerebral cortex had similar response patterns for most of the markers studied. Our data suggest that old and young animals present different time-courses of neuroinflammation and apoptosis after ischemic damage. On the other hand, these results suggest that neuroinflammation is dependent on age rather than on the different vulnerability described for the hippocampus and cerebral cortex. These differences should be taken into account in searching for therapeutic targets.

Reduction of adhesion molecule production and alteration of eNOS and endothelin-1 mRNA expression in endothelium by Euphorbia hirta L. through its beneficial β-amyrin molecule

The inflammatory reaction in large blood vessels involves up-regulation of vascular adhesion molecules such as endothelial cell selectin (E-selectin), soluble vascular cell adhesion molecule (sVCAM)-1, and soluble intercellular adhesion molecule (sICAM)-1. These vascular dysfunctions are associated with the development of atherosclerosis. β-Amyrin, an active component of Euphorbia hirta L., has potent anti-inflammatory effects. So far, its preventive effects against the expression of inflammatory mediator-induced adhesion molecules have not been investigated. Endothelial cells (SVEC4-10 cell line) were treated with 50% RAW conditioned media (i.e., normal SVEC4-10 culture media contains 50% of lipopolysaccharide-activated macrophage culture media) without or with β-amyrin (0.6 and 0.3 µM). The production levels of E-selectin, sICAM-1, and sVCAM-1 in the SVEC4-10 cells were measured with ELISA assay kits. Under the same treatment conditions, expression of endothelin (ET)-1 and endothelial type of NO synthase (eNOS) mRNA were analyzed by RT-PCR and agarose gel. With β-amyrin, the 50% RAW conditioned media-induced E-selectin, sICAM-1, and sVCAM-1 levels as well as ET-1 gene expression were all suppressed. β-Amyrin treatment also restored the 50% RAW conditioned media-suppressed eNOS mRNA expression. These data indicate that β-amyrin is potentially useful in preventing chronic inflammation-related vascular diseases.

P2Y(2)R activation by nucleotides released from oxLDL-treated endothelial cells (ECs) mediates the interaction between ECs and immune cells through RAGE expression and reactive oxygen species production

Lipoprotein oxidation, inflammation, and immune responses involving the vascular endothelium and immune cells contribute to the pathogenesis of atherosclerosis. In an atherosclerotic animal model, P2Y2 receptor (P2Y2R) upregulation and stimulation were previously shown to induce intimal hyperplasia and increased intimal monocyte infiltration. Thus, we investigated the role of P2Y2R in oxidized low-density lipoprotein (oxLDL)-mediated oxidative stress and the subsequent interaction between endothelial cells (ECs) and immune cells. The treatment of human ECs with oxLDL caused the rapid release of ATP (maximum after 5 min). ECs treated with oxLDL or the P2Y2R agonists ATP/UTP for 1h exhibited significant reactive oxygen species (ROS) production, but this effect was not observed in P2Y2R siRNA-transfected ECs. In addition, oxLDL and ATP/UTP both induced RAGE expression, which was P2Y2R dependent. Oxidized LDL- and ATP/UTP-mediated ROS production was diminished in RAGE siRNA-transfected ECs, suggesting that RAGE is an important mediator in P2Y2R-mediated ROS production. Treatment with oxLDL for 24h induced P2Y2R expression in the human monocyte cell line THP-1 and increased THP-1 cell migration toward ECs. The addition of apyrase, an enzyme that hydrolyzes nucleotides, or diphenyleneiodonium (DPI), a well-known inhibitor of NADPH oxidase, significantly inhibited the increase in cell migration caused by oxLDL. P2Y2R siRNA-transfected THP-1 cells did not migrate in response to oxLDL or ATP/UTP treatment, indicating a critical role for P2Y2R and nucleotide release in oxLDL-induced monocyte migration. Last, oxLDL and ATP/UTP effectively increased ICAM-1 and VCAM-1 expression and the subsequent binding of THP-1 cells to ECs, which was inhibited by pretreatment with DPI or by siRNA against P2Y2R or RAGE, suggesting that P2Y2R is an important mediator in oxLDL-mediated monocyte adhesion to ECs through the regulation of ROS-dependent adhesion molecule expression in ECs. Taken together, our findings suggest that P2Y2R could be a therapeutic target for the prevention of vascular disorders, including atherosclerosis.

Targeting JNK by a new curcumin analog to inhibit NF-kB-mediated expression of cell adhesion molecules attenuates renal macrophage infiltration and injury in diabetic mice

Macrophage infiltration contributes to the pathogenesis of diabetic renal injury. However, the regulatory mechanisms between macrophage infiltration and epithelial cell activation are still unclear. Our previous study found that C66, a novel curcumin analog, was able to inhibit inflammatory cytokine expression in vitro and in vivo. This study further elucidated whether C66 can prevent glucose-induced renal epithelial activation and inflammatory macrophage infiltration by a MAPK/NF-κB medicated mechanism. Our data show that pretreatment with C66 not only significantly reduced high glucose (HG)-induced over-expressions of VCAM-1, ICAM-1 and MCP-1, but also remarkably inhibited NF-κB activation, MAPKs phosphorylation, and subsequently macrophage adhesion in renal epithelial NRK-52E cells. Furthermore, we find that MAPKs, especially JNK, play important roles in HG-induced NF-κB activation, which regulates the over-expression of adhesion molecules in HG-stimulated NRK-52E cells. A molecular docking predicted that C66 may target JNK2, which leads to its anti-inflammatory actions. In vivo, administration of C66 or JNK special inhibitor SP600125 at 5 mg/kg markedly decreased diabetes-induced renal adhesion molecule expression, NF-κB activation, inflammatory cell infiltration, and pathological indexes in the kidneys of diabetic mice. These findings provide a perspective on the renoprotective effects of C66 in diabetes, and outline a novel therapeutic strategy of JNK inhibition for the treatment of diabetic nephropathy.

Expression of NFkappaB, ICAM1, and VCAM1 in rheumatic heart disease with atrial fibrillation

OBJECTIVE

To examine the expression of nuclear factor kappaB (NFkappaB), intercellular adhesion molecule 1 (ICAM1), and vascular cell adhesion molecule 1 (VCAM1) levels in rheumatic heart disease patients who suffer from atrial fibrillation and those who do not.

STUDY DESIGN

Twenty-six patients with rheumatic heart disease were enrolled. Ten patients had no history of atrial fibrillation and 16 had atrial fibrillation. Atrial tissue was obtained from the right atrial appendage during heart surgery. The expression levels of NFkappaB, ICAM1, and VCAM1 were examined with immunohistochemical staining.

RESULTS

Myocardial inflammation and fibrosis were both increased in patients with atrial fibrillation. The levels of NFkappaB, ICAM1, and VCAM1 were significantly elevated in patients with atrial fibrillation as compared with the control group (all p < 0.05).

CONCLUSION

Overexpression of NFkappaB, ICAM1, and VCAM1 may be involved in the development and maintenance of atrial fibrillation in patients with rheumatic heart disease.

Ceacam1 deletion causes vascular alterations in large vessels

Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) promotes hepatic insulin clearance and endothelial survival. However, its role in the morphology of macrovessels remains unknown. Mice lacking Ceacam1 (Cc1-/-) exhibit hyperinsulinemia, which causes insulin resistance and fatty liver. With increasing evidence of an association among hyperinsulinemia, fatty liver disease, and atherosclerosis, we investigated whether Cc1-/- exhibited vascular lesions in atherogenic-prone aortae. Histological analysis revealed impaired endothelial integrity with restricted fat deposition and aortic plaque-like lesions in Cc1-/- aortae, likely owing to their limited lipidemia. Immunohistochemical analysis indicated macrophage deposition, and in vitro studies showed increased leukocyte adhesion to aortic wall, mediated in part by elevation in vascular cell adhesion molecule 1 levels. Basal aortic eNOS protein and NO content were reduced, in parallel with reduced Akt/eNOS and Akt/Foxo1 phosphorylation. Ligand-induced vasorelaxation was compromised in aortic rings. Increased NADPH oxidase activity and plasma 8-isoprostane levels revealed oxidative stress and lipid peroxidation in Cc1-/- aortae. siRNA-mediated CEACAM1 knockdown in bovine aortic endothelial cells adversely affected insulin's stimulation of IRS-1/PI 3-kinase/Akt/eNOS activation by increasing IRS-1 binding to SHP2 phosphatase. This demonstrates that CEACAM1 regulates both endothelial cell autonomous and nonautonomous mechanisms involved in vascular morphology and NO production in aortae. Systemic factors such as hyperinsulinemia could contribute to the pathogenesis of these vascular abnormalities. Cc1-/- mice provide a first in vivo demonstration of distinct CEACAM1-dependent hepatic insulin clearance linking hepatic to macrovascular abnormalities.

Lycopene protects against LPS-induced proinflammatory cytokine cascade in HUVECs

The aim of the study was to explore whether lycopene protects against the activation of human umbilical vein endothelial cells (HUVECs) induced by a proinflammatory stimulus. HUVECs were pretreated with different concentrations of lycopene (1 microm or 10 microm), then incubated with 1 microg/ml LPS for 24 h. After an incubation, the mRNA and protein levels of proinflammatory cytokines (MCP-1, IL-6, VCAM-1), the expression KLF2, TLR4, ERK1/2 and NF-kappaB were assayed. The result showed that lycopene treatment significantly suppressed the response of HUVECs to LPS and reduced the levels of proinflammatory cytokines. Also, lycopene increased KLF2 expression, while it inhibited the activation TLR4 and its downstream ERK and the NF-kappaB signaling pathway in HUVECs.

The androgen metabolite, 5α-androstane-3β,17β-diol, decreases cytokine-induced cyclooxygenase-2, vascular cell adhesion molecule-1 expression, and P-glycoprotein expression in male human brain microvascular endothelial cells

P-glycoprotein (Pgp), a multiple drug resistance transporter expressed by vascular endothelial cells, is a key component of the blood-brain barrier and has been shown to increase after inflammation. The nonaromatizable androgen, dihydrotestosterone (DHT), decreases inflammatory markers in vascular smooth muscle cells, independent of androgen receptor (AR) stimulation. The principal metabolite of DHT, 5α-androstane-3β,17β-diol (3β-diol), activates estrogen receptor (ER)β and similarly decreases inflammatory markers in vascular cells. Therefore, we tested the hypothesis that either DHT or 3β-diol decrease cytokine-induced proinflammatory mediators, vascular cell adhesion molecule-1 (VCAM-1) and cyclooxygenase-2 (COX-2), to regulate Pgp expression in male primary human brain microvascular endothelial cells (HBMECs). Using RT-qPCR, the mRNAs for AR, ERα, and ERβ and steroid metabolizing enzymes necessary for DHT conversion to 3β-diol were detected in male HBMECs demonstrating that the enzymes and receptors for production of and responsiveness to 3β-diol are present. Western analysis showed that 3β-diol reduced COX-2 and Pgp expression; the effect on Pgp was inhibited by the ER antagonist, ICI-182,780. IL-1β-caused an increase in COX-2 and VCAM-1 that was reduced by either DHT or 3β-diol. 3β-diol also decreased cytokine-induced Pgp expression. ICI-182,780 blocked the effect of 3β-diol on COX-2 and VCAM-1, but not Pgp expression. Therefore, in cytokine-stimulated male HBMECs, the effect of 3β-diol on proinflammatory mediator expression is ER dependent, whereas its effect on Pgp expression is ER independent. These studies suggest a novel role of 3β-diol in regulating blood-brain barrier function and support the concept that 3β-diol can be protective against proinflammatory mediator stimulation.

Intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 at the early stages of atherosclerosis in a rat model

BACKGROUND

Members of the immunoglobulin superfamily of endothelial adhesion molecules, vascular cell adhesion molecule (VCAM-1) and intercellular cell adhesion molecule (ICAM-1), participate in leukocyte adhesion to the endothelium and play an important role in all stages of atherosclerosis. The aim of the study was to examine the expression of VCAM-1 and ICAM-1 in the aorta of rats at the early stages of atherosclerosis and the correlation with their plasma concentrations.

MATERIALS AND METHODS

Male rats (n=44), 10 weeks of age, were divided in 4 groups. Groups A and C (n=12) were fed with rich cholesterol diet for 12 and 16 weeks, respectively. Group B (regression group, n=12) was fed for the first 12 weeks with rich cholesterol diet and for another 4 weeks with normal diet. Group D (control group, n=8) was fed with normal diet for 12 weeks. We measured the serum lipid profile, the concentration of soluble ICAM-1 and the immunohistochemical expression of ICAM-1 and VCAM-1 in the endothelium, media and vasa vasorum of the aorta.

RESULTS

There were significant differences (p<0.05) in the expression of ICAM-1 between group C (maximum time of rich cholesterol diet) and all other groups in the 3 groups of the aorta studied. There was regression of the expression of ICAM-1 in group B and significant differences (p<0.05) between group B and all the other groups, except group D in the expression of ICAM-1. There were no significant differences in the expression of VCAM-1 between any groups. The serum concentration of soluble ICAM-1 positively correlated with the expression of the molecule in the vasa vasorum (r=0.35, p<0.05) and fibroblasts/smooth muscular cells (r=0.34, p<0.05) of the aorta.

CONCLUSION

A cholesterol diet plays a role in the expression of ICAM-1 but not in that of VCAM-1 in the rat aorta. The expression of ICAM-1 in the aorta regresses after the withdrawal of a cholesterol-rich diet. Soluble ICAM-1 is a reliable measure of ICAM-1 expression in the aorta, vasa vasorum and fibroblasts/smooth muscle cells.

Effects of chronic mental stress and atherogenic diet on the immune inflammatory environment in mouse aorta

Inflammation and stress are regarded as two important atherogenic factors. Because stress can affect leukocyte distribution, we hypothesized that stress-mediated leukocyte extravasation can modify the inflammatory environment of the arterial wall possibly contributing to atherogenesis. To test this hypothesis we evaluated the inflammatory environment of the aorta in C57Bl/6 mice subjected to 3 and 12 months of chronic stress and compared it to age matched non-stressed animals. Experiments were carried out in mice fed regular chow or atherogenic diets. Both treatments increased the expression of vascular and leukocyte adhesion molecules and leukocyte accumulation. At 3 months, stress but not an atherogenic diet elevated the number of CD4 cells, CD8 cells, macrophages, dendritic cells and neutrophils. These changes were associated with elevation of transcripts for ICAM-1 and VCAM-1, E-selectin and neuropeptide Y. At 12 months, stress or high cholesterol acted similarly to elevate the number of CD8 and macrophages, and synergistically on the number of all cell types investigated. At this time-point, strong synergism was also observed on the level of E-selectin and NPY in the aorta, but not in the circulation. Despite these effects, histological and morphological alterations of the arterial wall were severe in the atherogenic diet, but not in the stress groups. Thus, although stress and an atherogenic diet may both affect leukocyte accumulation in the aorta, they may contribute differently to atherogenesis.

Viscolin reduces VCAM-1 expression in TNF-α-treated endothelial cells via the JNK/NF-κB and ROS pathway

Viscolin, a major active component in a chloroform extract of Viscum coloratum, has antioxidative and anti-inflammatory properties. We focused on its effects on the expression of vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-α (TNF-α)-treated human umbilical vein endothelial cells (HUVECs). The TNF-α-induced expression of VCAM-1 was significantly reduced by respectively 38±7 or 34±16% when HUVECs were pretreated with 10 or 30μM viscolin, as shown by Western blotting, and was also significantly reduced by pretreatment with the antioxidants N-acetylcysteine, diphenylene iodonium chloride, and apocynin. Viscolin also reduced TNF-α-induced VCAM-1 mRNA expression and promoter activity, decreased reactive oxygen species (ROS) production, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, and significantly reduced the binding of monocytes to TNF-α-stimulated HUVECs. The attenuation of TNF-α-induced VCAM-1 expression and cell adhesion was partly mediated by a decrease in JNK phosphorylation. Furthermore, viscolin reduced VCAM-1 expression in the aorta of TNF-α-treated mice in vivo. Taken together, these data show that viscolin inhibits TNF-α-induced JNK phosphorylation, nuclear translocation of NF-κB p65, and ROS generation and thereby suppresses VCAM-1 expression, resulting in reduced adhesion of leukocytes. These results also suggest that viscolin may prevent the development of atherosclerosis and inflammatory responses.

Vascular endothelial cells cultured from patients with cerebral or uncomplicated malaria exhibit differential reactivity to TNF

Plasmodium falciparum malaria is a major cause of morbidity and mortality in African children, and factors that determine the development of uncomplicated (UM) versus cerebral malaria (CM) are not fully understood. We studied the ex vivo responsiveness of microvascular endothelial cells to pro-inflammatory stimulation and compared the findings between CM and UM patients. In patients with fatal disease we compared the properties of vascular endothelial cells cultured from brain tissue to those cultured from subcutaneous tissue, and found them to be very similar. We then isolated, purified and cultured primary endothelial cells from aspirated subcutaneous tissue of patients with CM (EC(CM) ) or UM (EC(UM) ) and confirmed the identity of the cells before analysis. Upon TNF stimulation in vitro, EC(CM) displayed a significantly higher capacity to upregulate ICAM-1, VCAM-1 and CD61 and to produce IL-6 and MCP-1 but not RANTES compared with EC(UM) . The shedding of endothelial microparticles, a recently described parameter of severity in CM, and the cellular level of activated caspase-3 were both significantly greater in EC(CM) than in EC(UM) . These data suggest that inter-individual differences in the endothelial inflammatory response to TNF may be an additional factor influencing the clinical course of malaria.

ICAM-1 and VCAM-1 expression in rat aortic endothelial cells after single-walled carbon nanotube exposure

The expanded application of carbon nanotubes and increased annual production has recently sparked public interest concerning associated and potentially adverse exposure effects. As very little is known with regard to the toxicology and underlying mechanism of the phenomena termed "single-walled carbon nanotube (SWCNT) exposure", we conducted an in depth investigation of potential SWCNT effects on cell adhesion molecule gene expression within rat aortic endothelial cells (RAECs). RAEC exposure to SWCNT induced neutrophil adhesion to the endothelial monolayer via increased ICAM-1 and VCAM-1 expression. Due to NF-kappaB's fundamental involvement in the transcriptional regulation of cell adhesion molecules, we studied NF-kappaB/P65 activation in SWCNT treated RAECs, as well as GSH and LDH as determinants of oxidative stress, a condition that influences NF-kappaB activation. Resultant data indicates SWCNT exposure induces oxidative stress, thereby altering ICAM-1 and VCAM-1 expression. SWCNT induced nuclear NF-kB/P65 translocation can be inhibited by N-acetylcysteine, indicating elevated ICAM-1 and VCAM-1 expression is mediated by oxidative stress in RAECs, and may play important inflammatory roles in SWCNT-induced vascular endothelium damage.

Quercetin blocks caveolae-dependent pro-inflammatory responses induced by co-planar PCBs

Polychlorinated biphenyls (PCBs) are widespread environmental contaminants, and co-planar PCBs can induce oxidative stress and activation of pro-inflammatory signaling cascades which are associated with atherosclerosis. The majority of the toxicological effects elicited by the co-planar PCB exposure are associated to the activation of the aryl hydrocarbon receptor (AHR) and subsequent induction of responsive genes. Previous studies from our group have shown that quercetin, a nutritionally relevant flavonoid can significantly reduce PCB77 induction of oxidative stress and expression of the AHR responsive gene cytochrome P450 1A1 (CYP1A1). We also have evidence that membrane domains called caveolae may regulate PCB-induced inflammatory parameters. Thus, we hypothesized that quercetin can modulate PCB-induced endothelial inflammation associated with caveolae. To test this hypothesis, endothelial cells were exposed to co-planar PCBs in combination with quercetin, and the expression of pro-inflammatory genes was analyzed by real-time PCR. Quercetin co-treatment significantly blocked both PCB77 and PCB126 induction of CYP1A1, vascular cell adhesion molecule 1 (VCAM-1), E-selectin and P-selectin. Exposure to PCB77 also induced caveolin-1 protein expression, which was reduced by co-treatment with quercetin. Our results suggest that inflammatory pathways induced by co-planar PCBs can be down-regulated by the dietary flavonoid quercetin through mechanisms associated with functional caveolae.

NAD(P)H:quinone oxidoreductase 1-compromised human bone marrow endothelial cells exhibit decreased adhesion molecule expression and CD34+ hematopoietic cell adhesion

NAD(P)H:quinone oxidoreductase 1 (NQO1) deficiency resulting from a homozygous NQO1*2 polymorphism has been associated with an increased risk of benzene-induced myeloid toxicity and a variety of de novo and therapy-induced leukemias. Endothelial cells in human bone marrow form one of the two known hematopoietic stem cell microenvironments and are one of the major cell types that express NQO1 in bone marrow. We have used a transformed human bone marrow endothelial cell (TrHBMEC) line to study the potential impact of a lack of NQO1 activity on adhesion molecule [endothelial leukocyte adhesion molecule 1 (E-selectin), vascular cell adhesion molecule (VCAM)-1, and intercellular adhesion molecule (ICAM)-1] expression and functional adhesion to bone marrow progenitor cells. We used both 5-methoxy-1,2-dimethyl-3-[(4-nitrophenoxy)methyl]indole-4,7-dione (ES936), a mechanism-based inhibitor of NQO1, and anti-NQO1 small interfering RNA to abrogate NQO1 activity. Real-time reverse transcription-polymerase chain reaction data demonstrated a significant inhibition of tumor necrosis factor (TNF)alpha-induced E-selectin mRNA levels after ES936 pretreatment. Immunoblot assays demonstrated a significant reduction in TNFalpha-stimulated E-selectin, VCAM-1, and ICAM-1 proteins after inhibition or knockdown of NQO1. The mechanisms underlying this effect remain undefined, but modulation of nuclear factor-kappaB (p65), c-Jun, and activating transcription factor 2, transcriptional regulators of adhesion molecules, were observed after inhibition or knockdown of NQO1. Decreased level of E-selectin, VCAM-1, and ICAM-1 also resulted in a functional deficit in adhesion. A parallel plate flow chamber study demonstrated a marked reduction in CD34(+) cell (KG1a) adhesion to NQO1-deficient TrHBMECs relative to controls. The reduced adhesive ability of TrHBMECs may affect the function of the vascular stem cell niche and also may contribute to the increased susceptibility of polymorphic individuals lacking NQO1 to leukemias and hematotoxicants such as benzene.

Endostar, a recently introduced recombinant human endostatin, inhibits proliferation and migration through regulating growth factors, adhesion factors and inflammatory mediators in choroid-retinal endothelial cells

Retinal neovascularization is one of the leading causes for complete blindness in a number of diseases around the world. Endostar, a recently introduced recombinant human endostatin, has been considered as one of the most valuable anti-angiogenic agents. In this study, we demonstrate that Endostar inhibits both the proliferation of the choroid-retinal endothelial cells through limiting the progression of the cell cycle and their migration. Furthermore, Endostar induces the expression of the pigment epithelial-derived factor (PEDF) and suppresses the expression of the vascular endothelial growth factor (VEGF) and the fibroblast growth factor (FGF). Endostar also reduces the expression of the inflammatory mediator tumor necrosis factor-alpha (TNF-alpha), matrix metalloproteinases (MMPs) and vascular cell adhesion molecule-1 (VCAM-1). These findings reveal an integrated role of Endostar in the program of retinal vascular control and highlight its significant potential for broad clinical application.

14-3-3 mediates apelin-13-induced enhancement of adhesion of monocytes to human umbilical vein endothelial cells

To investigate whether apelin-13 induced THP-1 monocytes (MCs) adhesion to ECV304 human umbilical vein endothelial cells (HUVECs) via 14-3-3 signaling transduction pathway and the potential novel physiological function and signaling transduction pathway of apelin-APJ, HUVECs ECV304 were cultured in DMEM and MCs THP-1 were cultured in RPMI 1640 medium. Monocyte adhesion and the expression of vascular cell adhesion molecule-1 (VCAM-1) and 14-3-3 were measured with monocyte adhesion assay and western blot analysis. Data showed that apelin-13 increased adhesion of MCs to HUVECs in a concentration- and time-dependent manner, which reached their peaks at 1 mM and 12 h, respectively. Similarly, apelin-13 induced the expression of HUVECs adhesion molecule, VCAM-1, in a concentration- and time-dependent manner, reached their peaks at 1 microM and 12 h, respectively. Apelin-13 induced the expression of 14-3-3 in a concentration- and timedependent manner, which reached their peaks at 1 mM and 5 min, respectively. Furthermore, the potent 14-3-3 inhibitor difopein significantly reduced the expression of 14-3-3 and VCAM-1 in apelin-13 stimulated HUVECs, and difopein significantly inhibited the effect of apelin-13 on induction of MCs adhesion to HUVECs. These data suggested that 14-3-3 mediated the induction of adhesion of MCs to HUVECs by Apelin-13.

Tetrahydrobiopterin supplementation reduces atherosclerosis and vascular inflammation in apolipoprotein E-knockout mice

BH4 (tetrahydrobiopterin) supplementation improves endothelial function in models of vascular disease by maintaining eNOS (endothelial nitric oxide synthase) coupling and NO (nitric oxide) bioavailability. However, the cellular mechanisms through which enhanced endothelial function leads to reduced atherosclerosis remain unclear. We have used a pharmaceutical BH4 formulation to investigate the effects of BH4 supplementation on atherosclerosis progression in ApoE-KO (apolipoprotein E-knockout) mice. Single oral dose pharmacokinetic studies revealed rapid BH4 uptake into plasma and organs. Plasma BH4 levels returned to baseline by 8 h after oral dosing, but remained markedly increased in aorta at 24 h. Daily oral BH4 supplementation in ApoE-KO mice from 8 weeks of age, for a period of 8 or 12 weeks, had no effect on plasma lipids or haemodynamic parameters, but significantly reduced aortic root atherosclerosis compared with placebo-treated animals. BH4 supplementation significantly reduced VCAM-1 (vascular cell adhesion molecule 1) mRNA levels in aortic endothelial cells, markedly reduced the infiltration of T-cells, macrophages and monocytes into plaques, and reduced T-cell infiltration in the adjacent adventitia, but importantly had no effect on circulating leucocytes. GCH (GTP cyclohydrolase I)-transgenic mice, with a specific increase in endothelial BH4 levels, exhibited a similar reduction in vascular immune cell infiltration compared with BH4-deficient controls, suggesting that BH4 reduces vascular inflammation via endothelial cell signalling. In conclusion, BH4 supplementation reduces vascular immune cell infiltration in atherosclerosis and may therefore be a rational therapeutic approach to reduce the progression of atherosclerosis.

Celecoxib activates PI-3K/Akt and mitochondrial redox signaling to enhance heme oxygenase-1-mediated anti-inflammatory activity in vascular endothelium

Although nonsteroidal anti-inflammatory drugs (NSAIDs) provide important control of pain and inflammation, they have been overshadowed by concerns regarding atherothrombotic complications. However, celecoxib seems to have a relatively good cardiovascular profile and may improve endothelial function in coronary heart disease. This led us to the hypothesis that celecoxib induces the vasculoprotective enzyme heme oxygenase-1 (HO-1). In human umbilical vein and aortic endothelial cells, 24-48 h treatment with celecoxib induced HO-1 mRNA and protein expression and increased HO-1 enzyme activity. This effect was not seen with rofecoxib or indomethacin. Supplementation of culture medium with iloprost or prostaglandin E(2) failed to reverse celecoxib-mediated HO-1 induction, indicating a cyclooxygenase-independent mechanism. Rather, this action of celecoxib involved generation of mitochondria-derived reactive oxygen species, Akt phosphorylation, and nuclear translocation of the transcription factor Nrf2, with N-acetylcysteine, PI-3K antagonist LY290042, and dominant-negative Akt abrogating the effects. Furthermore, celecoxib-induced HO-1 was inhibited by dominant-negative Nrf2. The functional significance of HO-1 induction was revealed by celecoxib-mediated inhibition of VCAM-1 expression, a response reversed by the HO-1 antagonist zinc protoporphyrin. HO-1 induction provides a molecular mechanism for clinical observations indicating relative freedom from atherothrombotic complications in patients taking celecoxib compared to other NSAIDs with comparable anti-inflammatory activity.

Aging attenuates radiation-induced expression of pro-inflammatory mediators in rat brain

The present study was designed to examine the effect of aging on radiation-induced expression of pro-inflammatory mediators in rat brain. Male F344xBN rats (4, 16, and 24 months of age) received either whole brain irradiation with a single dose of 10Gy gamma-rays or sham-irradiation, and were maintained for 4, 8, and 24h post-irradiation. The mRNA expression levels of various pro-inflammatory mediators such as cytokines, adhesion molecules, chemokine, and matrix metalloproteinase were analyzed by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR). The acute inflammatory responses to irradiation, including overexpression of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, monocyte chemoattractant protein-1 (MCP-1), and matrix metalloproteinase-9 (MMP-9) were markedly attenuated in the hippocampus of middle-aged and old rats compared with young groups. Specifically, a significant age-dependent decrease in TNF-alpha expression was detected 8 and 24h after irradiation and a similar age-related attenuation was observed in IL-1beta, ICAM-1, and VCAM-1 expression 4 and 8h post-irradiation. MCP-1 expression was reduced 4h post-irradiation and MMP-9 expression at 8h post-irradiation. These results provide evidence for the first time that radiation-induced pro-inflammatory responses in the brain are suppressed in aged animals.

Effects of long-term ethanol consumption on adhesion molecules in liver

Adhesion molecules play an important role in the pathogenesis of several diseases. In this study, expression of adhesion molecules was examined in the setting of chronic alcohol induced liver damage of male albino Wistar strain rats (16-18 weeks-old, 200-220 g) in a time dependent manner. Decreased protein level and increased activities of liver marker enzymes in response to the chronic ethanol (1.6 g ethanol/kg body weight/day) exposure, indicated that these animals suffered from liver damage in a time-dependent manner. Flow cytometric analysis revealed that chronic ethanol treatment induced intercellular adhesion molecule-1, vascular cell adhesion molecule-1 and platelet endothelial cell adhesion molecule-1 expression in liver tissues of rats with duration of ethanol exposure. The results suggest that the adhesion molecules may be associated with the initiation of hepatic injury during alcohol intoxication.

Resolution of remodeling in eosinophilic esophagitis correlates with epithelial response to topical corticosteroids

BACKGROUND

Esophageal remodeling occurs in eosinophilic esophagitis (EE) patients but whether the components of remodeling in the subepithelium are reversible by administration of topical oral corticosteroids is unknown.

METHODS

We quantitated the degree of lamina propria remodeling in esophageal biopsies obtained before and after at least 3 months of therapy with budesonide in 16 pediatric EE subjects. In addition, we investigated whether corticosteroid therapy modulated vascular activation (expression of VCAM-1; level of interstitial edema), TGFbeta(1) activation (levels of TGFbeta(1), phosphorylated Smad2/3), and performed a pilot analysis of a polymorphism in the TGFbeta(1) promoter in relation to EE subjects who had reduced remodeling with budesonide therapy.

RESULTS

EE subjects were stratified based on the presence (n = 9) or absence (n = 7) of decreased epithelial eosinophilia following budesonide. Patients with residual eosinophil counts of <or=7 eosinophils per high power field in the epithelial space (responders) demonstrated significantly reduced esophageal remodeling with decreased fibrosis, TGFbeta(1) and pSmad2/3 positive cells, and decreased vascular activation in association with budesonide therapy. Responders were more likely to have a CC genotype at the -509 position in the TGFbeta(1) promoter.

CONCLUSIONS

Reductions in epithelial eosinophils following budesonide therapy were associated with significantly reduced esophageal remodeling.

Microglia and microglia-like cell differentiated from DC inhibit CD4 T cell proliferation

The central nervous system (CNS) is generally regarded as a site of immune privilege, whether the antigen presenting cells (APCs) are involved in the immune homeostasis of the CNS is largely unknown. Microglia and DCs are major APCs in physiological and pathological conditions, respectively. In this work, primary microglia and microglia-like cells obtained by co-culturing mature dendritic cells with CNS endothelial cells in vitro were functional evaluated. We found that microglia not only cannot prime CD4 T cells but also inhibit mature DCs (maDCs) initiated CD4 T cells proliferation. More importantly, endothelia from the CNS can differentiate maDCs into microglia-like cells (MLCs), which possess similar phenotype and immune inhibitory function as microglia. Soluble factors including NO lie behind the suppression of CD4 T cell proliferation induced by both microglia and MLCs. All the data indicate that under physiological conditions, microglia play important roles in maintaining immune homeostasis of the CNS, whereas in a pathological situation, the infiltrated DCs can be educated by the local microenvironment and differentiate into MLCs with inhibitory function.

Placental apoptosis and adhesion molecules expression in the placenta and the maternal placental bed of pregnancies complicated by fetal growth restriction with and without pre-eclampsia

The aim of the study was to examine the expression of adhesion molecules VCAM-1 and ICAM-3 in placental tissue samples and placental bed (maternal decidual tissue) biopsies of pregnancies complicated by pre-eclampsia (PE) and fetal growth restriction (FGR), and to determine whether PE and FGR are associated with an increase in placental apoptosis. We studied placentas and placental bed samples of 49 third trimester pregnancies complicated by FGR (26 with associated PE, 23 without PE) and 25 normotensive healthy pregnant women. Placental apoptosis was assessed by the TUNEL method. Immunohistochemistry was used to assess expression of the VCAM-1 and ICAM-3. There was no significant difference in the staining intensity of VCAM-1 in placentas (p=0.472) and placental bed biopsies (p=0.754) of women delivering appropriate for gestational age and growth restricted fetuses (with and without associated PE). The amount of lymphocytes staining positively with ICAM-3 was significantly higher in both placental and placental bed biopsies of women delivering growth restricted fetuses compared with control pregnancies (p<0.001). Fetal growth restricted pregnancies with associated PE showed higher staining of ICAM-3 in placental compared with placental bed samples (p=0.049). In fetal growth restricted placentas, apoptotic nuclei were more abundant compared with control placentas (p<0.001). Increased expression of ICAM-3 on lymphocyte surface of both maternal and fetal side, suggests lymphocyte overactivation in PE and FGR. Increased placental apoptosis may play an important role in the pathogenesis or sequelae of PE.

Pioglitazone reduces inflammatory responses of human adipocytes to factors secreted by monocytes/macrophages

Infiltration of monocyte-derived macrophages into adipose tissue may contribute to tissue and systemic inflammation and insulin resistance. We hypothesized that pioglitazone (Pio) could specifically reduce the inflammatory response of adipocytes to factors released by monocytes/macrophages. We show that macrophage factors (Mphi-factors) greatly increase expression levels of proinflammatory adipokines, chemokines, and adhesion molecules in human subcutaneous and visceral adipose tissue (SAT and VAT) as well as in adipocytes (up to several hundredfold of control). Compared with SAT, VAT showed enhanced basal and Mphi-factor-induced inflammatory responses. Mphi-factors also induced greater lipolysis in adipocytes, as assessed by concentrations of glycerol released from the cells (196 +/- 13 vs. 56 +/- 7 microM in control, P < 0.05). Pretreatment of adipose tissue or adipocytes with Pio reduced these responses to Mphi-factors (by 13-86%, P < 0.05) and prevented Mphi-factor suppression of adiponectin expression. Furthermore, Pio pretreatment of adipocytes and macrophages tended to further reduce inflammatory responses of adipocytes to Mphi-factors and monocyte adhesion to Mphi-factor-activated adipocytes. In support of these in vitro data, media conditioned by monocytes isolated from impaired glucose-tolerant subjects treated with Pio (compared with placebo) induced release of lower concentrations of proinflammatory adipokines and glycerol (100 +/- 7 vs. 150 +/- 15 microM, P < 0.05) from adipocytes. In summary, Pio decreases inflammatory responses in adipose tissue/cells induced by monocytes/macrophages by acting on either or both cell types. These beneficial effects of Pio may attenuate proinflammatory responses resulting from monocyte/macrophage infiltration into adipose tissue and suppress tissue inflammation resulting from the interaction between both cell types.

Dietary antioxidants decrease serum soluble adhesion molecule (sVCAM-1, sICAM-1) but not chemokine (JE/MCP-1, KC) concentrations, and reduce atherosclerosis in C57BL but not apoE*3 Leiden mice fed an atherogenic diet

Dietary antioxidants are reported to suppress cellular expression of chemokines and adhesion molecules that recruit monocytes to the artery wall during atherosclerosis. In the present study we measured the effect of feeding apoE*3 Leiden mice or their non-transgenic (C57BL) littermates with atherogenic diets either deficient in, or supplemented with, dietary antioxidants (vitamin E, vitamin C and β-carotene) for 12 weeks, on serum levels of CC (JE/MCP-1) and CXC (KC) chemokines and soluble adhesion molecules (sVCAM-1, sICAM-1) and atherosclerotic lesion size. ApoE*3 Leiden mice developed gross hypercholesterolaemia, and markedly accelerated (10–20 fold; P < 0.0001) atherogenesis, compared with non-transgenic animals. Antioxidant consumption reduced lesion area in non-transgenic, but not apoE*3 Leiden, mice. Serum sVCAM-1 and sICAM-1 levels were significantly (P < 0.0001) increased (sVCAM-1 up to 3.9 fold; sICAM-1 up to 2.4 fold) by 4—8 weeks in all groups, and then declined. The initial increase in the concentration of adhesion molecules was reduced by 38%— 61% (P < 0.05) by antioxidant consumption, particularly in non-transgenic mice. By contrast, serum chemokine levels tended to increase more rapidly from baseline in apoE*3 Leiden mice, compared with non-transgenic animals, but were unaffected by dietary antioxidants. We conclude that dietary antioxidants reduce circulating soluble adhesion molecules and atherosclerosis in C57BL mice.

Increased expression of cell adhesion molecules in inflammatory myopathies: diagnostic utility and pathogenetic insights

CONTEXT

Idiopathic inflammatory myopathies (IMs) have been postulated to be of autoimmune origin on the basis of expression of markers like MHC-1 and other mediators involved in autoimmunity such as cell adhesion molecules.

AIMS

The present study aims to analyze the expression of cell adhesion molecules ICAM-1 and VCAM-1 and their respective ligands LFA-1 and VLA-4 in IMs, and to assess whether these markers, besides MHC-class 1 antigen and membrane attack complex (MAC), could be of any help in the diagnosis of these diseases.

MATERIAL AND METHODS

Retrospective analysis of 119 muscle biopsies consisting of 55 IMs (21 dermatomyositis, 31 polymyositis and 3 inclusion body myositis) and 64 controls received in our department from January 2004 to December 2005 was carried out immunohistochemically using monoclonal antibodies.

STATISTICAL ANALYSIS

Chi square test and test for validity were used for analysis of differences in expression.

RESULTS

Expression of ICAM and VCAM was significantly upregulated on blood vessels and muscle fibres in IMs as compared to controls, in which expression was weak or absent. LFA and VLA-4 were expressed in inflammatory cells in all inflammatory diseases in almost equal numbers.

CONCLUSIONS

IMs comprise 6% of all muscle diseases and IBM is not a common IM in India as reported in the Western literature. Our findings support the hypothesis of autoimmune origin of IMs. The difference between expression of these molecules in IMs and controls also has diagnostic implications and these markers should be included along with MHC-1 antigen and membrane attack complex (MAC) in the existing diagnostic armamentarium.