A Molecular Communication Perspective on Synchronization of Coupled Microfluidic-Spectroscopy.

A challenge for real-time monitoring of biochemical processes, such as cells, is detection of biologically relevant molecules. This is due to the fact that spectroscopy methods for detection may perturb the cellular environment. One approach to overcome this problem is coupled microfluidic-spectroscopy, where a microfluidic output channel is introduced in order to observe biologically relevant molecules. This approach allows for non-passive spectroscopy methods, such as mass spectrometry, to identify the structure of molecules released by the cell. Due to the non-negligible length of the microfluidic channel, when a sequence of stimuli are applied to a cell it is not straightforward to determine which spectroscopy samples correspond to a given stimulus. In this paper, we propose a solution to this problem by taking a molecular communication (MC) perspective on the coupled microfluidic-spectroscopy system. In particular, assignment of samples to a stimulus is viewed as a synchronization problem. We develop two new algorithms for synchronization in this context and carry out a detailed theoretical and numerical study of their performance. Our results show improvements over maximum-likelihood synchronization algorithms in terms of detection performance when there are uncertainties in the composition of the microfluidic channel.

Circular RNA CircCDKN2B-AS_006 Promotes the Tumor-like Growth and Metastasis of Rheumatoid Arthritis Synovial Fibroblasts by Targeting the miR-1258/RUNX1 Axis.

Rheumatoid arthritis (RA) is an autoimmune polyarthritis in which synovial fibroblasts (SFs) play a major role in cartilage and bone destruction through tumor-like proliferation, migration, and invasion. Circular RNAs (circRNAs) have emerged as vital regulators for tumor progression. However, the regulatory role, clinical significance, and underlying mechanisms of circRNAs in RASF tumor-like growth and metastasis remain largely unknown. Differentially expressed circRNAs in synovium samples from patients with RA and patients with joint trauma were identified via RNA sequencing. Subsequently, in vitro and in vivo experiments were performed to investigate the functional roles of circCDKN2B-AS_006 in RASF proliferation, migration, and invasion. CircCDKN2B-AS_006 was upregulated in synovium samples from patients with RA and promoted the tumor-like proliferation, migration, and invasion of RASFs. Mechanistically, circCDKN2B-AS_006 was shown to regulate the expression of runt-related transcription factor 1 (RUNX1) by sponging miR-1258, influencing the Wnt/ß-catenin signaling pathway, and promoting the epithelial-to-mesenchymal transition (EMT) in RASFs. Moreover, in the collagen-induced arthritis (CIA) mouse model, intra-articular injection of lentivirus-shcircCDKN2B-AS_006 was capable of alleviating the severity of arthritis and inhibiting the aggressive behaviors of SFs. Furthermore, the correlation analysis results revealed that the circCDKN2B-AS_006/miR-1258/RUNX1 axis in the synovium was correlated with the clinical indicators of RA patients. CircCDKN2B-AS_006 promoted the proliferation, migration, and invasion of RASFs by modulating the miR-1258/RUNX1 axis.

Estrogen antagonizes ASIC1a-induced chondrocyte mitochondrial stress in rheumatoid arthritis.

BACKGROUND: Destruction of articular cartilage and bone is the main cause of joint dysfunction in rheumatoid arthritis (RA). Acid-sensing ion channel 1a (ASIC1a) is a key molecule that mediates the destruction of RA articular cartilage. Estrogen has been proven to have a protective effect against articular cartilage damage, however, the underlying mechanisms remain unclear. METHODS: We treated rat articular chondrocytes with an acidic environment, analyzed the expression levels of mitochondrial stress protein HSP10, ClpP, LONP1 by q-PCR and immunofluorescence staining. Transmission electron microscopy was used to analyze the mitochondrial morphological changes. Laser confocal microscopy was used to analyze the Ca2+, mitochondrial membrane potential (Δψm) and reactive oxygen species (ROS) level. Moreover, ASIC1a specific inhibitor Psalmotoxin 1 (Pctx-1) and Ethylene Glycol Tetraacetic Acid (EGTA) were used to observe whether acid stimulation damage mitochondrial function through Ca2+ influx mediated by ASIC1a and whether pretreatment with estrogen could counteract these phenomena. Furthermore, the ovariectomized (OVX) adjuvant arthritis (AA) rat model was treated with estrogen to explore the effect of estrogen on disease progression. RESULTS: Our results indicated that HSP10, ClpP, LONP1 protein and mRNA expression and mitochondrial ROS level were elevated in acid-stimulated chondrocytes. Moreover, acid stimulation decreased mitochondrial membrane potential and damaged mitochondrial structure of chondrocytes. Furthermore, ASIC1a specific inhibitor PcTx-1 and EGTA inhibited acid-induced mitochondrial abnormalities. In addition, estrogen could protect acid-stimulated induced mitochondrial stress by regulating the activity of ASIC1a in rat chondrocytes and protects cartilage damage in OVX AA rat. CONCLUSIONS: Extracellular acidification induces mitochondrial stress by activating ASIC1a, leading to the damage of rat articular chondrocytes. Estrogen antagonizes acidosis-induced joint damage by inhibiting ASIC1a activity. Our study provides new insights into the protective effect and mechanism of action of estrogen in RA.

Nesfatin-1 exerts protective effects on acidosis-stimulated chondrocytes and rats with adjuvant-induced arthritis by inhibiting ASIC1a expression.

Nesfatin-1, a newly identified energy-regulating peptide, has been reported to possess antioxidant, anti-inflammatory, and antiapoptotic properties; however, to date, its effect on rheumatoid arthritis (RA) has not been previously explored in detail. We previously showed that activation of acid-sensing ion channel 1a (ASIC1a) by acidosis plays an important role in RA pathogenesis. Therefore, in this study, we evaluated the effects of nesfatin-1 on acidosis-stimulated chondrocyte injury in vitro and in vivo and examined the involvement of ASIC1a and the mechanism underlying the effects of nesfatin-1 on RA. Acid-stimulated articular chondrocytes were used to examine one of the several possible mechanisms underlying RA pathogenesis in vitro. The mRNA expression profile of acid-induced chondrocytes treated or not treated with nesfatin-1 was investigated by RNA sequencing. The effects of nesfatin-1 on oxidative stress, inflammation, and apoptosis in acid-induced chondrocytes were measured. The mechanistic effect of nesfatin-1 on ASIC1a expression and intracellular Ca2+ in acid-stimulated chondrocytes was studied. Rats with adjuvant-induced arthritis (AA) were used for in vivo analysis of RA pathophysiology. Cartilage degradation and ASIC1a expression in chondrocytes were detected in rats with AA after intraarticular nesfatin-1 injection. The in vitro experiments showed that nesfatin-1 decreased acidosis-induced cytotoxicity and elevation of intracellular Ca2+ levels in chondrocytes. Moreover, it attenuated acid-induced oxidative stress, inflammation, and apoptosis in chondrocytes. Nesfatin-1 decreased ASIC1a protein levels in acid-stimulated chondrocytes via the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and nuclear factor kappa-B (NF-κB) signaling pathways. In vivo analysis showed that nesfatin-1 ameliorated cartilage degradation and decreased ASIC1a expression in the chondrocytes of rats with AA. Collectively, nesfatin-1 suppressed acidosis-induced oxidative stress, inflammation, and apoptosis in acid-stimulated chondrocytes and alleviated arthritis symptoms in rats with AA, and its mechanism may be related to its ability to decrease ASIC1a protein levels via the MAPK/ERK and NF-κB pathways.

ASIC1a promotes the proliferation of synovial fibroblasts via the ERK/MAPK pathway.

Synovial hyperplasia, a profound alteration in the structure of synovial tissue, is the basis for cumulative joint destruction in rheumatoid arthritis (RA). It is generally accepted that controlling synovial hyperplasia can delay the progression of RA. As one of the most intensively studied isoforms of acid-sensing ion channels (ASICs), ASIC1a contributes to various physiopathologic conditions, including RA, due to its unique property of being permeable to Ca2+. However, the role and the regulatory mechanisms of ASIC1a in synovial hyperplasia are poorly understood. Here, rats induced with adjuvant arthritis (AA) and human primary synovial fibroblasts were used in vivo and in vitro to investigate the role of ASIC1a in the proliferation of RA synovial fibroblasts (RASFs). The results show that the expression of ASIC1a was significantly increased in synovial tissues and RASFs obtained from patients with RA as well as in the synovium of rats with AA. Moreover, extracellular acidification improved the ability of RASFs colony formation and increased the expression of proliferation cell nuclear antigen (PCNA) and Ki67, which was abrogated by the specific ASIC1a inhibitor psalmotoxin-1 (PcTX-1) or ASIC1a-short hairpin RNA (ASIC1a-shRNA), suggesting that extracellular acidification promotes the proliferation of RASFs by activating ASIC1a. In addition, the activation of c-Raf and extracellular signal-regulated protein kinases (ERKs) signaling was blocked with PcTX-1 or ASIC1a-shRNA and the proliferation of RASFs was further inhibited by the ERK inhibitor (U0126), indicating that ERK/MAPK signaling contributes to the proliferation process of RASFs promoted by the activation of ASIC1a. These findings gave us an insight into the role of ASIC1a in the proliferation of RASFs, which may provide solid foundation for ASIC1a as a potential target in the treatment of RA.

Estrogen protects against acidosis-mediated articular chondrocyte injury by promoting ASIC1a protein degradation.

Epidemiological data suggest that the incidence of rheumatoid arthritis (RA) increases in postmenopausal women, which may be related to estrogen deficiency. Tissue acidosis is a common symptom of RA. Acid-sensitive ion channel 1a (ASIC1a), a member of the extracellular H+-activated cation channel family, could be activated by changes in extracellular pH and plays a crucial role in the pathogenesis of RA. As the only cellular component in cartilage tissue, chondrocytes play an extremely important role in maintaining cartilage tissue homeostasis. The aim of this study was to investigate whether estrogen could protect acid-stimulated chondrocytes by regulating the expression of ASIC1a and explore the possible mechanism. The results showed that estrogen could protect against acid-induced chondrocyte injury by reducing ASIC1a protein expression. Moreover, lysosome inhibitor chloroquine (CQ) and autophagy inhibitor 3-methyladeniine (3-MA) could reverse the reduction of ASIC1a protein caused by estrogen, indicating that autophagy-lysosome pathway contributes to estrogen-induced degradation of ASIC1a protein. Furthermore, the down-regulation of ASIC1a expression by estrogen was attenuated by MPP, a specific inhibitor of estrogen-related receptor-alpha (Esrra), indicating that Esrra is involved in the process of estrogen regulating the expression of ASIC1a. Additionally, adenosine 5'-monophosphate (AMP)-activated protein kinase/unc-51-like kinase 1 (AMPK-ULK1) signaling pathway was activated by estrogen treatment, which was abrogated by Esrra-silencing, and AMPK-specific inhibitor Compound C pretreatment could reduce estrogen-induced downregulation of ASIC1a protein. Taken together, these results indicate that estrogen could promote autophagy-lysosome pathway-dependent ASIC1a protein degradation and protect against acidosis-induced cytotoxicity, the mechanisms of which might relate to Esrra-AMPK-ULK1 signaling pathway.

Acidosis induces synovial fibroblasts to release vascular endothelial growth factor via acid-sensitive ion channel 1a.

Acid-sensitive ion channel 1a (ASIC1a) is a member of the extracellular H+ activated cation channel family. Studies have shown that tissue acidification contributes to the formation of microvessels in rheumatoid arthritis (RA) synovial tissue, but its underlying mechanisms remain unclear. The purpose of this study was to investigate the role of tissue acidification in microvascular formation of arthritic synovial tissue and the effect of ASIC1a on vascular endothelial growth factor (VEGF) release from arthritic synovial tissue. Our results indicate that ASIC1a expression, VEGF expression, and microvessel density (MVD) are elevated in RA synovial tissue and adjuvant arthritis (AA) rat synovial tissue. When AA rats were treated with ASIC1a-specific blocker psalmotoxin-1 (PcTx-1), the expression of ASIC1a, VEGF expression, and MVD were all reduced. Acidification of RA synovial fibroblasts (RASF) can promote the release of VEGF. PcTx-1 and ASIC1a-short hairpin RNA can inhibit acid-induced release of VEGF. In addition, the ASIC1a overexpression vector can promote acid-induced VEGF release. This indicates that extracellular acidification induces the release of VEGF by RASF via ASIC1a. These findings suggest that blocking ASIC1a mediates the release of VEGF from synoviocytes may provide a potential therapeutic strategy for RA therapy.

ATPR induces acute promyelocytic leukemia cells differentiation and growth arrest by blockade of SHP2/Rho/ROCK1 pathway.

Acute promyelocytic leukemia (APL) is a form of acute myeloid leukemia with a unique chromosome translocation t (15;17), commonly complicated by a complex coagulopathy. 4-Amino-2-trifuoromethyl-phenyl retinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative, was synthesized by our group and known to possess obvious biological anti-tumor activities. It has previously been shown that ATPR could induce differentiation and inhibit proliferation of APL cells, although the mechanism responsible for this effect was not well understood. In this study, we demonstrated that ATPR remarkably inhibited the expression and activity of SHP2. Further experiments showed silencing SHP2 or using SHP2 inhibition (SHP099) enhanced the effect of ATPR on cell proliferation and maturation. In addition, we also demonstrated that Rho/ROCK1 might be regulated by SHP2. Using Y-27632, a ROCK inhibitor, further proved that ROCK1 played an important role in ATPR-induced differentiation and proliferation suppression. In conclusion, the results from this study revealed that ATPR induced APL cells terminal differentiation and growth arrest by blockade of SHP2/Rho/ ROCK1 pathway.

17ß-estradiol attenuates rat articular chondrocyte injury by targeting ASIC1a-mediated apoptosis.

Epidemiological evidence suggests that the etiology and pathogenesis of rheumatoid arthritis (RA) are closely associated with estrogen metabolism and deficiency. Estrogen protects against articular damage. Estradiol replacement therapy ameliorates local inflammation and knee joint swelling in ovariectomized models of RA. The mechanistic basis for the protective role of 17ß-estradiol (17ß-E2) is poorly understood. Acid-sensing ion channel 1a (ASIC1a), a sodium-permeable channel, plays a pivotal role in acid-induced articular chondrocyte injury. The aims of this study were to evaluate the role of 17ß-E2 in acid-induced chondrocyte injury and to determine the effect of 17ß-E2 on the level and activity of ASIC1a protein. Results showed that pretreatment with 17ß-E2 attenuated acid-induced damage, suppressed apoptosis, and restored mitochondrial function. Further, 17ß-E2 was shown to reduce protein levels of ASIC1a through the ERα receptor, to protect chondrocytes from acid-induced apoptosis, and to induce ASIC1a protein degradation through the autophagy-lysosomal pathway. Taken together, these results show that the use of 17ß-E2 may be a novel strategy for the treatment of RA by reducing cartilage destruction through down-regulation of ASIC1a protein levels.

ASIC1a induces synovial inflammation via the Ca2+/NFATc3/ RANTES pathway.

Rationale: Synovial inflammation is one of the main pathological features of rheumatoid arthritis (RA) and is a key factor leading to the progression of RA. Understanding the regulatory mechanism of synovial inflammation is crucial for the treatment of RA. Acid-sensing ion channel 1a (ASIC1a) is an H+-gated cation channel that promotes the progression of RA, but the role of ASIC1a in synovial inflammation is unclear. This study aimed to investigate whether ASIC1a is involved in the synovial inflammation and explore the underlying mechanisms in vitro and in vivo. Methods: The expression of ASIC1a and nuclear factor of activated T cells (NFATs) were analyzed by Western blotting, immunofluorescence, and immunohistochemistry both in vitro and in vivo. The Ca2+ influx mediated by ASIC1a was detected by calcium imaging and flow cytometry. The role of ASIC1a in inflammation was studied in rats with adjuvant-induced arthritis (AA). Inflammatory cytokine profile was analyzed by protein chip in RA synovial fibroblasts (RASF) and verified by a magnetic multi-cytokine assay and ELISA. The NFATc3-regulated RANTES (Regulated upon activation, normal T cell expressed and secreted) gene transcription was investigated by ChIP-qPCR and dual-luciferase reporter assay. Results: The expression of ASIC1a was significantly increased in human RA synovial tissues and primary human RASF as well as in ankle synovium of AA rats. Activated ASIC1a mediated Ca2+ influx to increase [Ca2+]i in RASF. The activation/overexpression of ASIC1a in RASF up-regulated the expression of inflammatory cytokines RANTES, sTNF RI, MIP-1a, IL-8, sTNF RII, and ICAM-1 among which RANTES was increased most remarkably. In vivo, ASIC1a promoted inflammation, synovial hyperplasia, articular cartilage, and bone destruction, leading to the progression of AA. Furthermore, activation of ASIC1a upregulated the nuclear translocation of NFATc3, which bound to RANTES promoter and directly regulated gene transcription to enhance RANTES expression. Conclusion: ASIC1a induces synovial inflammation, which leads to the progression of RA. Our study reveals a novel RA inflammation regulatory mechanism and indicates that ASIC1a might be a potential therapeutic target for RA.

4-Amino-2-trifluoromethyl-phenyl retinate induced differentiation of human myelodysplastic syndromes SKM-1 cell lines by up-regulating DDX23.

Myelodysplastic syndrome (MDS) is a heterogeneously cloned hematopoietic stem cell malignancy with a high risk of developing acute myeloid leukemia (AML). 4-amino-2-trifluoromethyl-phenyl resinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative designed in our group, was proved to be a tumor inhibitor in diverse types of cancer cells in vitro. However, little has been known about the effects of ATPR on MDS. To analyze if and to what extent it's anti-tumor activity on MDS, we performed CCK-8, Flow Cytometry, Wright-Giemsa staining, qRT-PCR, and Western blot to analyze the SKM-1 cells state after ATPR treatment in multiplex detection angles. As expected, our results proved that ATPR could effectively induce cell differentiation and reduce cell proliferation of SKM-1 cell lines. Subsequently, to further analyze the potential mechanisms, we applied Label-free proteomic techniques to discover relevant protein that may be involved. Most notably, a series of factors related to RNA behavioral regulation were changed. Among them, we demonstrated that DEAD-box RNA helicase DDX23 was abnormally ablated in MDS patients and could be restored after ATPR treatment in vitro. Besides, our results suggested that ATPR-induced SKM-1 cell maturation was counteracted when knockdown DDX23, underscoring that DDX23 might be involved. In conclusion, we confirmed that ATPR could induce SKM-1 cells differentiation and its positive influence of DDX23 may provide a new idea to relieve MDS.

ASIC1a promotes synovial invasion of rheumatoid arthritis via Ca2+/Rac1 pathway.

Acid-sensitive ion channels (ASICs) as Ca2+ and Na+ cation channels are activated by changing in extracellular pH, which expressed in various diseases and participated in underlying pathogenesis. ASIC1a is involved in migration and invasion of various tumor cells. Rheumatoid arthritis fibroblast-like synoviocytes (RA-FLSs) located at the edge of the synovium were identified as key players in the pathophysiological process of rheumatoid arthritis and reported to have many similar properties to tumor cells. Here, we investigated the roles of ASIC1a in synovial invasion in vivo and the migration and invasion of RA-FLSs in vitro. Our results showed ASIC1a highly expressed in RA synovial tissues and RA-FLSs. Inhibition of ASIC1a by PCTX-1 reduces synovial invasion and the expressions of MMP2, MMP9, p-FAK to protect articular cartilage in AA rats. Moreover, the acidity-promoted invasion and migration as well as the expressions of MMP2, MMP9, p-FAK of RA-FLSs were down-regulated by ASIC1a-RNAi and PCTX-1 while they were increased by overexpression-ASIC1a. ASIC1a mediated Ca2+ influx and the activation of Ras-related C3 botulinum toxin substrate 1(Rac1), which was decreased by the intracellular calcium chelating agent BAPTA-AM. Meanwhile, the migration and invasion as well as the expressions of MMP2, MMP9, p-FAK of RA-FLSs were decreased by Rac1 specific blocker NSC23766. In conclusion, this study indicated that ASIC1a may be a master regulator of synovial invasion via Ca2+/Rac1 pathway.

Effects of autophagy on apoptosis of articular chondrocytes in adjuvant arthritis rats.

Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease that eventually leads to joint deformities and loss of joint function. Previous studies have demonstrated a close relationship between autophagy and the development of RA. Although autophagy and apoptosis are two different forms of programmed death, the relationship between them in relation to RA remains unclear. In this study, we explored the effect of autophagy on apoptosis of articular chondrocytes in vivo and in vitro. Adjuvant arthritis (AA) and acid-induced primary articular chondrocyte apoptosis were used as in vivo and in vitro models, respectively. Articular chondrocyte autophagy and apoptosis were both observed dynamically in AA rat articular cartilage at different stages (15 days, 25 days and 35 days). Moreover, chondrocyte apoptosis and articular cartilage injury in AA rats were increased by the autophagy inhibitor 3-methyladenine (3-MA) and decreased by the autophagy activator rapamycin. In addition, pre-treatment with 3-MA increased acid-induced chondrocyte apoptosis, while pre-treatment with rapamycin reduced acid-induced chondrocyte apoptosis in vitro. These results suggest that autophagy might be a potential target for the treatment of RA.

A novel all-trans retinoic acid derivative inhibits proliferation and induces apoptosis of myelodysplastic syndromes cell line SKM-1 cells via up-regulating p53.

Myelodysplastic syndromes (MDS) are a varied set of hematologic neoplasms and a high risk of progression to acute myeloid leukemia (AML). 4-Amino-2-trifluoromethyl-phenyl retinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative, play an important role in various types of cancer cells as a tumor inhibitor. However, little is known concerning its antitumor effect on MDS. The cell viability and the percentage of apoptotic cells were used to measure MTT, Flow Cytometry and Hoechst 33342/PI staining. In addition, real-time quantitative RT-PCR (qRT-PCR) and western blotting were used to analyzed the expression of p53, as well as the levels of BNIP3, apoptosis proteins of Caspase-3, BAX and BCL-2. After SKM-1 cells were incubated with DAC, ATRA and ATPR, the viability of the SKM-1 cells was inhibited in a dose- and time-dependent manner. Both Hoechst staining and flow cytometry showed the apoptosis of SKM-1 cells was increased. Moreover, SKM-1 cells treated with ATPR unveiled elevated mRNA and protein levels of p53, BNIP3, BAX and Caspase-3 expression and decreased BCL-2 expression. However, silencing p53 suppressed the pro-apoptosis function of ATPR. Consequently, these data provide the first evidence for ATPR increased apoptosis in SKM-1 cells by p53 that is mutually dependent on and obligatorily linked to BNIP3 gene activation.

Chronic inflammatory status in patients with coronary artery ectasia.

BACKGROUND: Coronary artery ectasia (CAE) is well-recognized, angiographic finding of abnormal coronary dilatation. The role of inflammation in atherosclerosis is increasingly well known. However, the association between inflammation and CAE has been controversial. METHOD: Fifty-five patients with CAE and non-obstructive coronary artery disease (CAD), 38 with obstructive CAD, and 33 angiographically normal coronary controls were enrolled in the study. The peripheral blood was taken, and white blood cell count (WBCC) as well as other leukocyte subtypes including neutrophils, lymphocytes, and monocyte cell count (MCC) were measured. The plasma levels of C-reactive protein (CRP) and interleukin-6 (IL-6) were determined by ELISA. RESULTS: The higher number of WBCC, neutrophil and MCC were found in patients with CAE compared with obstructive CAD patients as well as normal controls (p<0.01, respectively). Moreover, levels of plasma CRP and IL-6 were also significantly higher in patients with CAE than that in patients with obstructive CAD, and subjects without coronary artery disease (p<0.001, respectively). Univariate analysis showed that the sex, current smoking, numbers of WBCC, neutrophil, MCC, levels of CRP and IL-6 were related with CAE, while MCC was independently linked with a diagnosis of CAE. CRP was the independent variable most strongly associated with CAE by multivariate analysis. CONCLUSIONS: Taken together, this study confirmed and expanded previous limited findings that a more significant chronic inflammation might be linked with the pathogenesis of CAE that was associated with not only inflammatory markers but also inflammatory cells in patients with CAE.

Increased peripheral circulating inflammatory cells and plasma inflammatory markers in patients with variant angina.

BACKGROUND: Emerging data suggest that inflammation may play an important role in the pathogenesis of coronary artery disease. However, the relation of inflammatory status to coronary vasospasm has been less investigated in patients with variant angina (VA). PURPOSE: The aim of this study, therefore, was to determine peripheral circulating white blood cells as well as monocyte cells and plasma C-reactive protein (CRP) and interleukin-6 (IL-6) levels in patients with VA, and to compare patients with VA, stable coronary artery disease, and controls with angiographically normal coronary arteries. METHOD: Thirty-three consecutive patients with documented VA, 26 with stable coronary artery disease, and 22 normal controls (with angiographically normal coronary arteries) were involved in this study. The peripheral blood was taken, and white blood cells and monocyte cells were counted. The plasma concentrations of CRP and IL-6 were also evaluated by enzyme-linked immunosorbent assay (ELISA). RESULTS: The data showed that white blood cell counts and monocyte cell counts were significantly higher in patients of the VA group than in the other two groups (white blood cell counts: 7340+/-1893/mm vs. 6187+/-1748/mm vs. 5244+/-1532/mm, P<0.05, respectively; monocyte cell counts: 510+/-213/mm vs. 425+/-209/mm vs. 383+/-192/mm, P<0.05, respectively). Similarly, levels of plasma CRP and IL-6 were also significantly higher in patients of the VA group than in patients with stable coronary artery disease (CRP: 0.42+/-0.21 mg/l vs. 0.27+/-0.14 mg/l; IL-6: 10.4+/-1.0 pg/dl vs. 6.2+/-0.7 pg/dl, P<0.01, respectively), and patients with normal controls (CRP: 0.42+/-0.21 mg/l vs. 0.17+/-0.10 mg/l; IL-6: 10.4+/-1.0 pd/dl vs. 3.0+/-0.7 pg/dl, P<0.01, respectively). The multivariate analysis showed that CRP was the independent variable most strongly associated with VA. CONCLUSION: Taken together, these findings suggested that more chronic, severe inflammation might be involved in the pathogenesis of VA, manifested by increased counts of circulating inflammatory cells and elevated plasma levels of CRP and IL-6.