Cyclophilin A Impairs Efferocytosis and Accelerates Atherosclerosis by Overexpressing CD 47 and Down-Regulating Calreticulin.

Impairment of efferocytosis in apoptotic macrophages is a known determinant of the severity of atherosclerosis and the vulnerability of plaques to rupture. The precise mechanisms involved in impaired efferocytosis are unclear. Given the well-recognized role of the inflammatory cytokine cyclophilin A (Cyp A) in modulating several atherogenic mechanisms in high-glucose primed monocytes, we investigated the role of Cyp A in macrophage efferocytosis. The efficiency of efferocytosis in RAW 264.7 macrophages grown in vitro and primed with cyclophilin A was assessed using flow cytometry and confocal assays. Cholesterol content in cells was measured using cell-based cholesterol efflux assay. Proteomic analysis and bioinformatics tools were employed to decipher the link between cyclophilin A and the known ligand receptors involved in efferocytosis. Cyclophilin A was found to impair efferocytosis in apoptotic macrophages by reducing ABCA1-mediated cholesterol efflux in foam cells derived from macrophages. Cyclophilin A-primed macrophages showed an increase in expression of the don't-eat-me signal CD 47 and a decrease in the expression of the eat-me signal, calreticulin. Phagocytosis was restored upon silencing of cyclophilin A. New Zealand white rabbits were fed a high-fat diet, and lesions in their aortae were analyzed histologically for evidence of atherosclerosis and the expression of Cyp A, CD 47 and calreticulin, the ligand receptor involved in efferocytosis. Gene and protein expressions in aortae and macrophages were analyzed by real-time PCR and Western blotting. Cyclophilin A, via its effects on the expression of CD 47 and calreticulin, impairs efferocytosis in apoptotic macrophages. Together with its impact on cholesterol efflux from macrophages, these effects can amplify other mechanisms of Cyp A in accelerating the progression of atherosclerosis.

Levels of S100 calcium binding protein B (S100B), neuron-specific enolase (NSE), and cyclophilin A (CypA) in the serum of patients with severe craniocerebral injury and multiple injuries combined with delirium transferred from the ICU and their prognostic value.

BACKGROUND: To analyze the levels of S100 calcium binding protein B (S100B), neuron-specific enolase (NSE), and cyclophilin A (CypA) in the serum of patients with severe craniocerebral injury combined with delirium and multiple injuries transferred from the intensive care unit (ICU), and their prognostic value. METHODS: The data of 98 patients with severe craniocerebral injury combined with delirium and multiple injuries admitted to our hospital from January 2018 to May 2019 were retrospectively analyzed as the study group. The differences in serum S100B, NSE, and CypA levels in each group were compared, and the deaths of the study group during follow-up were counted. RESULTS: The levels of S100B, NSE, and CypA in the study group were higher than those in the control group (P<0.05). The mortality rate of the 98 patients with severe craniocerebral injury combined with delirium and multiple injuries transferred from the ICU was 37.76%. Furthermore, the levels of S100B, NSE, and CypA in the death group were higher than those in the survival group (P<0.05). Glasgow Coma Score (GCS) score ≤5 points, Injury Severity Score (ISS) score >25 points, multiple organ dysfunction syndrome, and increased levels of S100B, NSE, and CypA were independent risk factors that affected the prognosis of patients with severe craniocerebral injury combined with delirium and multiple injuries transferred from the ICU (P<0.05). The average survival times of the high S100B level group, the high NSE level group, and the high CypA level group were shorter than those of the low-level groups (P<0.05). CONCLUSIONS: The levels of S100B, NSE, and CypA in serum were closely related to the prognosis of patients with severe craniocerebral injury combined with delirium and multiple injuries transferred from the ICU. They can be used as molecular markers for predicting the prognosis of patients, and may serve as potential targets for treatment.

Predictive value of early second trimester maternal serum cyclophilin A concentrations in women complicated with preeclampsia: a preliminary case-control study.

OBJECTIVE: To investigate cyclophilin A in early second trimester of pregnancy before the onset of preeclampsia. METHODS: In this prospective case-control study, 51 pregnant women whose serum were collected and stored and who developed preeclampsia in later follow-up and 41 pregnant women as control group were included. RESULTS: Maternal serum cyclophilin A levels in the study group who developed preeclampsia in later follow-up were significantly higher than those of normal healthy pregnant women. CONCLUSION: Cyclophilin A may be a valuable predictor for pregnant women who subsequently develop preeclampsia in their pregnancies.

Oxidative Stress and Inflammatory Markers PTX3, CypA, and HB-EGF: How Are They Linked in Patients With STEMI?

We investigated circulating levels of inflammatory biomarkers pentraxin-3 (PTX3), cyclophilin A (CypA), and heparin-binding epidermal growth factor-like growth factor (HB-EGF); oxidative stress; and antioxidant status markers in the patients with ST-segment elevation acute myocardial infarction (STEMI) to better understand a relationship between inflammation and oxidative stress. We examined the impact of oxidative stress on high values of inflammatory parameters. The study included 87 patients with STEMI and 193 controls. We observed a positive correlation between PTX3 and HB-EGF (ρ = 0.24, P = .027), CyPA, and sulfhydryl (SH) groups (ρ = 0.25, P = .026), and a negative correlation between PTX3 and SH groups (ρ = -0.35, P = .001) in patients with STEMI. To better understand the effect of the examined parameters on the occurrence of high concentrations of inflammatory parameters, we grouped them using principal component analysis. This analysis identified the 4 most contributing factors. Optimal cutoff values for discrimination of patients with STEMI from controls were calculated for PTX3 and HB-EGF. An independent predictor for PTX3 above the cutoff value was a "metabolic-oxidative stress factor" comprised of glucose and oxidative stress marker prooxidant-antioxidant balance (odds ratio = 4.449, P = .030). The results show that higher PTX3 values will occur in patients having STEMI with greater metabolic and oxidative stress status values.

Concentrations of Serum Cyclophilin A in Patients With Bell Palsy.

BACKGROUND: Cyclophilin A (CyPA) is the responder protein to stimuli that cause inflammation. To date, no association among CyPA and Bell palsy has been reported. METHODS: The concentrations of Serum CyPA were measured in 90 healthy participants and 92 patients with Bell palsy. Serum samples of patients and the control group were compared on the basis of CyPA levels. Facial latency and amplitude values on electromyography were evaluated and compared with serum CyPA concentrations. RESULTS: A total of 28, 37, 19, and 8 patients had grade 3, 4, 5, and 6 facial palsy cases, respectively. Comparing the control group and the patient group showed significant differences in CyPA values (P < 0.001). Cyclophilin A value can be evaluated as a marker with high disease discrimination capability. The results also showed that at low CyPA, the average recovery time was shorter than that of high CyPA (41.6 ±â€Š5.7 days vs 62.8 ±â€Š10.2 days, P = 0.036). We found no statistically significant relationship between electromyography parameters and CyPA level. (Facial latency: r: -0.014, P: 0.948; facial amplitude r: -0.081, P: 0.713). CONCLUSION: Serum CyPA concentrations increased in response to inflammation in Bell palsy patients. However, CyPA could not be used as an early prognostic marker in Bell palsy, low CyPA indicates the shorter average recovery time than that of high CyPA.

Association of cyclophilin A level and pulse pressure in predicting recurrence of cerebral infarction.

Cyclophilin A (CypA), secreted from vascular smooth muscle cells and inflammatory cells in response to oxidative stress, promotes vascular atherosclerosis and development of carotid stenosis. Increased concentration of plasma CypA in acute cerebral infarction was demonstrated clinically. The primary aim of this study was to investigate the prognostic impact between CypA level and outcome in patients with acute ischemic stroke. Admission serum CypA concentrations were detected in 66 acute cerebral infarction patients and in 52 healthy individuals. Inflammatory biomarkers, including high-sensitivity C-reactive protein, adhesion molecules, interleukins, and matrix-metalloproteases, were also assessed. We also examined the relationship between plasma biomarkers, blood pressure (BP), pulse pressure, the carotid artery velocity, the prognostic assessment with modified Rankin scale, and stroke recurrence. Plasma CypA concentration was higher on the first day of hospitalization in the high BP stroke group than in normal BP stroke group, which was statistically significant, which was observed even in the third month and sixth month follow-up outpatient periods. For stroke recurrence prediction, there was an important association between the higher (>60) pulse pressure on the seventh day of hospitalization and CypA level on the third month and sixth month follow-up outpatient periods. Our study revealed higher circulating serum levels of CypA in the hypertensive stroke group than in the non-hypertensive stroke group. We expect that elevated plasma CypA level and raised pulse pressure during hospitalization to become valuable biomarkers in predicting stroke recurrence in the sixth month assessment of acute cerebral infarction.

Cyclophilin A as a biomarker for the therapeutic effect of balloon angioplasty in chronic thromboembolic pulmonary hypertension.

BACKGROUND: Although cardiac troponin and natriuretic peptide have been shown to decrease after balloon pulmonary angioplasty (BPA) with improved right ventricular afterload in chronic thromboembolic pulmonary hypertension (CTEPH), biomarkers to evaluate the effects of BPA independently of heart failure status remain to be developed. METHODS: In 39 consecutive CTEPH patients including 31 who underwent BPA, we measured plasma levels of cyclophilin A (CyPA), which we demonstrated is secreted from pulmonary vascular smooth muscle cells in response to mechanical stretch and hypoxia. RESULTS: CyPA levels were elevated in CTEPH patients (12.7, IQR: 7.6-16.0) compared with 8 thromboembolic controls with a history of venous thromboembolism (4.9, IQR: 2.4-11.2) or 18 healthy controls (4.1, IQR: 2.4-6.8) (both p< 0.05) and were linearly correlated with mean pulmonary arterial pressure (r=0.50, p = 0.0003) and pulmonary vascular resistance (r=0.32, p= 0.026). BPA reduced CyPA levels and tended to lower brain-type natriuretic peptide (BNP) levels (p< 0.01 and p = 0.07). When comparing the changes in CyPA before and after BPA in the two subgroups with higher (≥35pg/mL) and normal (<35pg/mL) BNP at baseline, CyPA decreased both in patients with higher BNP and those with normal BNP (both p< 0.05). In contrast, BNP decreased only in patients with higher BNP (p< 0.05). Also, CyPA decreased both in patients with lower (<25 kg/m2) and higher (≥25kg/m2) body mass index (BMI) at baseline (both p<0.05), whereas BPA tended to reduce BNP in patients with lower BMI (p = 0.12) but not in those with higher BMI (p = 0.55). CONCLUSIONS: CyPA could be a useful biomarker to evaluate the effects of BPA even in patients with normal BNP or high BMI.

High Serum Cyclophilin C levels as a risk factor marker for Coronary Artery Disease.

Cyclophilins (Cyps) are ubiquitous proteins that belong to the immunophilins family consistently associated with inflammatory and cardiovascular diseases. While levels of CypA have been extensively studied, less data are available for other Cyps. The purpose of this case-control study was to determine the relationship of Cyps (A, B, C and D) with coronary artery disease (CAD) and eight inflammation markers. Serum levels of Cyps, interleukins and metalloproteinases were measured in serum collected from 84 subjects. Participants were divided into two sub-groups based on CAD diagnosis: 40 CAD patients and 44 control volunteers. Serum levels of CypA, CypB and CypC, IL-1ß and IL-6 were significantly higher in CAD patients. Bivariate correlation analysis revealed a significant positive correlation between Cyps and several blood and biochemical parameters. When the ability of Cyps levels for CAD diagnosis was evaluated, higher sensitivity and selectivity values were obtained with CypC (c-statistic 0.891, p < 0.001) indicating that it is a good marker of CAD disease, while less conclusive results were obtained with CypA (c-statistic 0.748, p < 0.001) and CypB (c-statistic 0.655, p < 0.014). In addition, significant correlations of traditional CAD risk factors and CypC were observed. In summary, high levels of CypC are a risk factor for CAD and therefore it can be proposed as a new biomarker for this disease.

Association between polymorphism in Cyclophilin A gene and its serum and placental expression in Han Chinese women with severe preeclampsia.

OBJECTIVES: Cyclophilin A (CypA) plays important roles in inflammation and oxidative stress and is significantly increased in serum of preeclampsia (PE) patients. We aimed to investigate CypA genetic polymorphism and its serum and placenta expressions in severe PE of Han Chinese women. METHODS: A case-control study of 82 severe PE patients and 179 healthy pregnancies was conducted. Single-nucleotide polymorphism (SNP) sites of rs3735481, rs9638978 and rs11984372 were analyzed by TaqMan assay. CypA serum levels were determined by enzyme-linked immunosorbent assay (ELISA). CypA mRNA levels and protein expressions in placentas were assessed by quantitative real-time polymerase chain reaction (PCR), western blot, and immunofluorescence assay, respectively. RESULTS: There were significantly lower frequency of rs3735481 allele C (odds ratio (OR): 0.60, 95% confidence interval (CI): 0.36-0.98; p = .04), and significantly higher frequency of rs9638978 allele A in severe PE especially in early onset PE patients (OR: 2.23, 95% CI: 1.35-3.71, p = .002). Frequency of rs9638978 AA genotype was significantly higher in early onset PE (p < .001). CypA serum levels were significantly higher in severe PE especially in early onset PE (p < .001). Meanwhile, CypA serum levels were significantly lower in carriers with the AC genotype of rs3735481 (p = .019) and significantly higher in carriers with the AA genotype of rs9638978 (p = .017). CypA mRNA levels and protein expressions were found to be significantly increased in PE placentas (both p < .01). CONCLUSIONS: The CypA genetic polymorphisms of rs3735481 and rs9638978 may be associated with severe PE, and rs9638978 AA genotype may be associated with an increasing risk of early onset severe PE in Han Chinese women. High CypA levels in serum and placenta may contribute to the pathogenesis of severe PE. Our results may provide a new clue for the etiology of severe PE.

Cyclophilin A and CD147 associate with progression of diabetic nephropathy.

To find the associations of circulating cyclophilin A (CyP A) and CD147/EMMPRIN with renal outcomes in type 2 diabetes patients and possible pathogenesis involved. Total 131 patients were recruited since 2004. Glycated hemoglobin, blood glucose and urine albumin-creatinine ratio levels at baseline and every 3 months were measured. Plasma CyP A and CD147 were also measured at baseline. Patients were divided into two groups based upon the median level of the baseline plasma CyP A value: < 93.64 ng/mL (group A, n = 65), ≥ 93.64 ng/mL (group B, n = 66). The estimated glomerular filtration rate was calculated at each follow-up visit. Besides, mitochondrial function assay by cellular mitochondrial energy utility was studied when cells were exposed to glucose or exogenous CyP A or both. Multivariate analysis, using median level (93.64) ng/mL as the cut-off value, revealed that circulating CyP A and CD147 levels at baseline were associated with the baseline estimated glomerular filtration rate (eGFR) (p = .042 and p = .001 separately) in cross-sectional analysis. Longitudinally, higher baseline plasma CyP A level was also correlated to a rapid decline in eGFR (p = .016). The results were also significant when using the continuous plasma CyP A level (p = .003). In cells exposed to glucose, results of oxygen consumption rate (OCR) showed a significant reduction in basal respiration, maximal respiration and ATP production. Depressed OCR further occurred when incubated with both of CyP A and glucose. Plasma CyP A and CD147 can serve as indicators of renal disease progression in type 2 diabetes patients.

Serum cyclophilin A concentrations and prognosis of acute intracerebral hemorrhage.

BACKGROUND: Cyclophilin A is involved in brain injury. We investigated the relationship between serum cyclophilin A concentrations, hemorrhagic severity and clinical outcome in intracerebral hemorrhage (ICH). METHODS: We enrolled 105 ICH patients and 105 healthy individuals. Admission serum cyclophilin A concentrations were detected in ICH patients. Hemorrhagic severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) and hematoma volume. Modified Rankin Scale score > 2 was defined as a poor outcome. RESULTS: Serum cyclophilin A concentrations were significantly higher in patients than in controls. There was a close correlation of serum cyclophilin A concentrations with NIHSS scores and hematoma volume. Serum cyclophilin A emerged as an independent predictor for 6-month mortality, overall survival and poor outcome. Moreover, it had a strong discriminatory ability for 6-month mortality and poor outcome. Furthermore, it could significantly improve the prognostic predictive ability of NIHSS scores or hematoma volume alone. CONCLUSIONS: Increasted serum cyclophilin A concentrations are highly associated with stroke severity and prognosis after hemorrhagic stroke.

Predictive value of serum cyclophilin A concentrations after acute pancreatitis.

BACKGROUND: Cyclophilin A is identified as a biomarker for inflammation. We elucidated prognostic significance of serum cyclophilin A (CypA) concentrations in acute pancreatitis (AP). METHODS: In this prospective and observational study, serum CypA concentrations were quantified in 210 AP patients and 100 healthy controls. We recorded local complication, in-hospital mortality and organ failure. Disease severity was assessed using the traditional predictors, namely Acute Physiology and Chronic Health Care Evaluation II score, Ranson score, multiple organ dysfunction score and sequential organ failure assessment score. RESULTS: Serum CypA concentrations were significantly lower in controls than in AP group. CypA concentrations after AP were highly correlated with the traditional predictors and other inflammatory mediators, including blood erythrocyte sedimentation rate, procalcitonin levels, white blood cell count and C-reactive protein levels. Serum CypA emerged as an independent predictor for in-hospital local complication, organ failure and mortality. Under receiver operating characteristic curve, serum CypA possessed similar prognostic ability, as compared to the traditional predictors. Its predictive ability was almost similar to that of procalcitonin levels and significantly exceeded those of the other inflammatory mediators. Also, it significantly improved prognostic performance of the traditional predictors. CONCLUSIONS: Increased serum CypA concentrations have close relation to the severity, inflammation and prognosis, substantializing CypA as a potential prognostic biomarker of AP.

The 90-day prognostic value of serum cyclophilin A in traumatic brain injury.

BACKGROUND: Cyclophilin A is involved in many inflammatory diseases and its expression is up-regulated after brain injury. We determined if serum cyclophilin A could be used as a marker for severity and 90-day outcome in patients with traumatic brain injury (TBI). METHODS: Serum cyclophilin A concentrations were quantified in 105 severe TBI patients and 105 healthy individuals. Its association with Glasgow Coma Scale (GCS) score, 90-day mortality and 90-day poor outcome (Glasgow Outcome Scale score of 1-3) were investigated. RESULTS: Serum cyclophilin A concentrations were significantly higher in TBI patients than in healthy individuals. Cyclophilin A concentrations had a close relation to GCS scores and showed a high discriminatory ability for 90-day mortality and poor outcome according to area under receiver operating characteristic curve (AUC). Its AUC was in the range of GCS scores. Moreover, its combination with GCS scores significantly improved the predictive performance of GCS scores alone. In addition, serum cyclophilin A emerged as an independent predictor for 90-day mortality, overall survival and poor outcome. CONCLUSIONS: Increased serum cyclophilin A concentrations could reflect trauma severity and unfavorable outcome after head trauma, substantializing cyclophilin A as a potential biomarker for prognostic prediction of TBI.

Cyclophilin A: A Predictive Biomarker of Carotid Stenosis in Cerebral Ischemic Stroke.

BACKGROUND: Cyclophilin A plays a pathogenic role in the development and progression of atherosclerosis, which can be assessed by measuring carotid intima-media thickness. The primary aim of this study was to examine the interaction between plasma Cyclophilin A level and carotid intima-media thickness in patients with acute ischemic stroke. METHOD: Plasma concentration of Cyclophilin A was measured on admission in 66 consecutive patients who had been hospitalized for acute cerebral stroke and in 52 case-control subjects without a history of acute stroke. Subjects in both groups also underwent ultrasound B-mode imaging to measure the mean and maximum intima-media thickness of the carotid artery. Inflammatory biomarkers including high-sensitivity C-reactive protein and fibrinogen were also assessed. RESULTS: We found that the plasma concentration of Cyclophilin A was significantly higher in patients with acute ischemic stroke (p = 0.042). Increased Cyclophilin A was also correlated with carotid intima-media thickness in the patient group (p < 0.001). Among the risk factors for cerebral stroke examined in this study, only hypertension was significantly associated with plasma Cyclophilin A level. CONCLUSION: Increased plasma Cyclophilin A levels might be involved in the pathophysiology of acute ischemic stroke and Cyclophilin A might serve as a biomarker in risk assessment of acute stroke patients.

The first-trimester maternal serum cyclophilin A concentrations in women with complicated pregnancy as preeeclampsia.

BACKGROUND: Cyclophilin A (CyPA) is a potential mediator of inflammation. We assessed the predictive value of the first-trimester maternal serum CyPA concentrations for complicated pregnancy. METHODS: The first-trimester serum CyPA concentrations were quantified in 100 women with normal pregnancy and in 351 women with complicated pregnancy, including 102 pre-eclampsia women, 131 gestational hypertension (GH) women and 118 gestational diabetes mellitus (GDM) women. Its association with complicated pregnancy was ascertained using multivariate analysis. RESULTS: Median CyPA concentrations were significantly higher in women developing complicated pregnancy as pre-eclampsia, GH or GDM than in women with normal pregnancy. CyPA concentrations were independently correlated with C-reactive protein concentrations in complicated pregnancy as pre-eclampsia, GH or GDM women. Serum CyPA and body mass index were independently associated with the development of complicated pregnancy as pre-eclampsia, GH or GDM. Serum CyPA possessed significantly high area under receiver operating characteristic curve. Meanwhile, CyPA significantly improved the predictive value of body mass index. CONCLUSIONS: Serum CyPA might be utilized as a potential inflammatory biomarker for complicated pregnancy and assessment of serum CyPA might aid in the prediction of complicated pregnancy.

The clinical implication of serum cyclophilin A in patients with chronic obstructive pulmonary disease.

Background: Cyclophilin A (CyPA) is a secreted molecule that is regulated by inflammatory stimuli. Although inflammation has an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD), little is known regarding the relationship between serum CyPA and COPD. Methods: Ninety-three COPD patients with acute exacerbation were enrolled in the study and were reassessed during the convalescence phase. Eighty-eight controls were matched for age, gender, body mass index, smoking index and comorbidity. The basic clinical information and pulmonary function of all participants were collected. Serum levels of CyPA and other inflammation indexes were further measured. Results: Serum CyPA was significantly increased in convalescent COPD patients compared to healthy controls, and further elevated in COPD patients with acute exacerbation. Serum CyPA positively correlated with serum interleukin-6, matrix metalloproteinase-9 and high-sensitivity C-reactive protein in both the exacerbation and convalescence phases of COPD. Furthermore, it negatively correlated with percent value of forced expiratory volume in 1 second (FEV1%) predicted and FEV1/forced vital capacity in convalescent COPD patients. Conclusion: These results suggest that serum CyPA can be used as a potential inflammatory biomarker for COPD and assessment of serum CyPA may reflect the severity of inflammation in COPD.

Metformin attenuates effects of cyclophilin A on macrophages, reduces lipid uptake and secretion of cytokines by repressing decreased AMPK activity.

Growing evidence implicates cyclophilin A secreted by vascular wall cells and monocytes as a key mediator in atherosclerosis. Cyclophilin A in addition to its proliferative effects, during hyperglycemic conditions, increases lipid uptake in macrophages by increasing scavenger receptors on the cell's surface. It also promotes macrophage migration across endothelial cells and conversion of macrophages into foam cells. Given the known effects of metformin in reducing vascular complications of diabetes, we investigated the effect of metformin on cyclophilin A action in macrophages. Using an ex vivo model of cultured macrophages isolated from patients with type 2 diabetes with and without coronary artery disease (CAD), we measured the effect of metformin on cyclophilin A expression, lipid accumulation, expression of scavenger receptors, plasma cytokine levels and AMP-activated protein kinase (AMPK) activity in macrophages. In addition, the effects of metformin on migration of monocytes, reactive oxygen species (ROS) formation, lipid uptake in the presence of cyclophilin A inhibitors and comparison with pioglitazone were studied using THP-1 monocytes. Metformin reduced cyclophilin A expression in human monocyte-derived macrophages. Metformin also decreased the effects of cyclophilin A on macrophages such as oxidized low-density lipoprotein (oxLDL) uptake, scavenger receptor expression, ROS formation and secretion of inflammatory cytokines in high-glucose conditions. Metformin reversed cyclophilin A-induced decrease in AMPK-1α activity in macrophages. These effects of metformin were similar to those of cyclophilin A inhibitors. Metformin can thus function as a suppressor of pro-inflammatory effects of cyclophilin A in high-glucose conditions by attenuating its expression and repressing cyclophilin A-induced decrease in AMPK-1α activity in macrophages.

Selected reaction monitoring approach for validating peptide biomarkers.

We here describe a selected reaction monitoring (SRM)-based approach for the discovery and validation of peptide biomarkers for cancer. The first stage of this approach is the direct identification of candidate peptides through comparison of proteolytic peptides derived from the plasma of cancer patients or healthy individuals. Several hundred candidate peptides were identified through this method, providing challenges for choosing and validating the small number of peptides that might prove diagnostically useful. To accomplish this validation, we used 2D chromatography coupled with SRM of candidate peptides. We applied this approach, called sequential analysis of fractionated eluates by SRM (SAFE-SRM), to plasma from cancer patients and discovered two peptides encoded by the peptidyl-prolyl cis-trans isomerase A (PPIA) gene whose abundance was increased in the plasma of ovarian cancer patients. At optimal thresholds, elevated levels of at least one of these two peptides was detected in 43 (68.3%) of 63 women with ovarian cancer but in none of 50 healthy controls. In addition to providing a potential biomarker for ovarian cancer, this approach is generally applicable to the discovery of peptides characteristic of various disease states.

Correlations of Serum Cyclophilin A and Melatonin Concentrations with Hypertension-induced Left Ventricular Hypertrophy.

BACKGROUND AND AIMS: Cyclophilin A (CyPA) is an abundantly expressed pro-inflammatory cytokine and a major secreted oxidative stress-induced factor (SOXF). Melatonin is an important chronobiological regulatory molecule that is mainly released from the pineal gland and exerts antioxidant effects by acting as a radical scavenger. Based on accumulating evidence, both CyPA and melatonin play important roles in cardiovascular diseases. However, further investigations are required to determine whether CyPA and melatonin are associated with hypertension-induced left ventricular hypertrophy (LVH). METHODS: A total of 135 patients with essential hypertension were divided into an LVH (+) group and an LVH (-) group according to Doppler echocardiography results. Clinical data of the two groups were evaluated. RESULTS: High CyPA levels and low melatonin levels are independent risk factors for LVH (p = 0.000). In addition, body mass index (BMI) and systolic blood pressure (SBP) are correlated with the risk of LVH (p = 0.000). However, other factors did not display statistically significant associations (p >0.05). The Pearson correlation and linear regression analyses show that BMI, SBP, and CyPA levels were positively correlated with left ventricular mass (LVM) and the left ventricular mass index (LVMI) (p <0.05), whereas melatonin levels were negatively correlated with LVM and the LVMI (p = 0.000). Furthermore, according to the results of the Pearson correlation analysis, CyPA levels were negatively correlated with melatonin levels (p <0.01) in subjects with LVH. CONCLUSIONS: Based on these results, both CyPA and melatonin are closely related to the pathogenesis of LVH. As CyPA was negatively correlated with melatonin in patients with LVH, additional studies are required to determine whether melatonin may partially protect the myocardium by decreasing CyPA levels.