The connection between C-reactive protein and atherosclerosis

Immunologic burden links periodontitis to acute coronary syndrome: levels of CD4 + and CD8 + T cells in gingival granulation tissue

OBJECTIVE

To investigate the proportional variation of macrophage and T-lymphocytes subpopulations in acute coronary syndrome (ACS) patients, its association with periodontitis (P), and to compare with control individuals.

SUBJECTS AND METHODS

Three groups of subjects participated: one group consisted of 17 ACS patients with P (ACS + P), another group consisted of 22 no ACS + P patients, and a control group consisted of 23 participants with gingivitis (no ACS + G). Macrophage, CD4 + , and CD8 + T-lymphocytes and CD4 + /CD8 + ratio values in gingival tissue were determined histometrically.

RESULTS

Significant differences were found among three groups regarding the mean number of macrophage (no ACS + P > ACS + P > no ACS + G; p < 0.05) and CD8 + T-lymphocytes (no ACS + P > ACS + P > no ACS + G; p < 0.05). Significant variations were observed between the groups both CD4 + T-lymphocytes densities (ACS + P > no ACS + P and ACS + P > no ACS + G; p < 0.05) and CD4 + / CD8 + ratio (no ACS + P < no ACS + G and ACS + P < no ACS + G; p < 0.05).

CONCLUSIONS

The increased number of CD8 + T-lymphocytes in both group ACS + P and group no ACS + P resulted in a reduction of the CD4 + /CD8 + ratio in gingival tissue when compared with no ACS + G group.

CLINICAL RELEVANCE

The decrease of CD4 + /CD8 + ratio in gingival tissue reflects periodontitis and may be associated with severe adverse outcomes in people with ACS.

Assessment of a Daily Diary Study Including Biospecimen Collections in a Sample of Sexual and Gender Minority Young Adults: Feasibility and Acceptability Study

BACKGROUND

Young sexual minority men (YSMM) engage in cardiometabolic risk behaviors (eg, substance use) at higher rates than their heterosexual counterparts. Theory and previous research suggest that these risk behaviors may stem, in part, from exposure to minority stress (ie, discrimination based on sexual identity and other identities such as race).

OBJECTIVE

This pilot study examined the feasibility and acceptability of a virtual 2-day daily diary study that examined daily experiences with discrimination, cardiometabolic risk behaviors (ie, sleep, physical activity, and substance use behaviors), and patterns of physiological stress and inflammation among YSMM aged 18 to 35 years.

METHODS

Participants (n=20) were recruited from the greater New York metropolitan area and engaged in a 2-day daily diary protocol wherein they provided web-based consent, took a web-based baseline survey, and then, starting the next day, provided 3 saliva samples a day for 2 consecutive days to measure salivary cortisol, engaged in 3 daily diaries per day, and provided 1 blood spot sample via the finger prick method to measure high-sensitivity C-reactive protein. At follow-up, participants were interviewed via videoconferencing to ascertain their experiences and feelings related to the study protocol. Qualitative analyses explored the feasibility and acceptability of the study protocol, and exploratory quantitative analyses explored the descriptive statistics and Pearson correlations among the main study variables of interest.

RESULTS

The retention rate was high (19/20, 95%) in our study sample. Qualitative analyses demonstrated that participants were willing to engage in similar, longer-term studies (eg, studies that include both week and weekend days) in the future and suggested the feasibility and acceptability of our study protocol among YSMM. However, participants noted several areas for improvement (eg, redundancy of survey items and difficulty pricking one's finger) that should be considered in future research. Preliminary quantitative analyses revealed a moderate negative correlation between everyday discrimination and mean cortisol levels (r=-0.51; P=.03). Furthermore, descriptive analyses suggest that that daily cortisol curves differ across races or ethnicities among YSMM. White and other-identified YSMM experienced the highest cortisol awakening response (mean 0.39, SD 0.21 µg/dL for White participants; mean 0.34, SD 0.34 µg/dL for others) with the steepest decline around bedtime (mean 0.05, SD 0.04 µg/dL for White participants; mean 0.09, SD 0.13 µg/dL for others) followed by a lower cortisol awakening response (mean 0.31, SD 0.11 µg/dL for Hispanic participants; mean 0.23, SD 0.15 µg/dL for Black participants) and a slower decline around bedtime (mean 0.10, SD 0.09 µg/dL for Hispanic participants; mean 0.03, SD 0.02 µg/dL for Black participants) among Hispanic and Black YSMM.

CONCLUSIONS

Overall, the results suggest that similar study protocols are feasible and acceptable among YSMM. Future research should highlight the pathways through which cardiovascular disease risk may arise among YSMM using longer-term study designs and more diverse study samples.

Use of 3D Printing Techniques to Fabricate Implantable Microelectrodes for Electrochemical Detection of Biomarkers in the Early Diagnosis of Cardiovascular and Neurodegenerative Diseases

This Review provides a comprehensive overview of 3D printing techniques to fabricate implantable microelectrodes for the electrochemical detection of biomarkers in the early diagnosis of cardiovascular and neurodegenerative diseases. Early diagnosis of these diseases is crucial to improving patient outcomes and reducing healthcare systems' burden. Biomarkers serve as measurable indicators of these diseases, and implantable microelectrodes offer a promising tool for their electrochemical detection. Here, we discuss various 3D printing techniques, including stereolithography (SLA), digital light processing (DLP), fused deposition modeling (FDM), selective laser sintering (SLS), and two-photon polymerization (2PP), highlighting their advantages and limitations in microelectrode fabrication. We also explore the materials used in constructing implantable microelectrodes, emphasizing their biocompatibility and biodegradation properties. The principles of electrochemical detection and the types of sensors utilized are examined, with a focus on their applications in detecting biomarkers for cardiovascular and neurodegenerative diseases. Finally, we address the current challenges and future perspectives in the field of 3D-printed implantable microelectrodes, emphasizing their potential for improving early diagnosis and personalized treatment strategies.

AIF1: Function and Connection with Inflammatory Diseases

Macrophages are a type of immune cell distributed throughout all tissues of an organism. Allograft inflammatory factor 1 (AIF1) is a calcium-binding protein linked to the activation of macrophages. AIF1 is a key intracellular signaling molecule that participates in phagocytosis, membrane ruffling and F-actin polymerization. Moreover, it has several cell type-specific functions. AIF1 plays important roles in the development of several diseases: kidney disease, rheumatoid arthritis, cancer, cardiovascular diseases, metabolic diseases and neurological disorders, and in transplants. In this review, we present a comprehensive review of the known structure, functions and role of AIF1 in inflammatory diseases.

Opium consumption and long-term outcomes of CABG surgery in patients without modifiable risk factors

Background

The question about the significance of opium consumption as a coronary artery disease (CAD) risk factor still remains open. The present study aimed to evaluate the association between opium consumption and long term outcomes of coronary artery bypass grafting (CABG) in patients without standard modifiable CAD risk factors (SMuRFs; hypertension, diabetes, dyslipidemia, and smoking).

Methods

In this registry-based design, we included 23,688 patients with CAD who underwent isolated CABG between January 2006 to December 2016. Outcomes were compared in two groups; with and without SMuRF. The main outcomes were all-cause mortality, fatal and nonfatal cerebrovascular events (MACCE). Inverse probability weighting (IPW) adjusted Cox's proportional hazards (PH) model was used to evaluate the effect of opium on post-op outcomes.

Results

During 133,593 person-years of follow-up, opium consumption was associated with increased risk of mortality in both patients with and without SMuRFs (weighted Hazard Ratio (HR)s: 1.248 [1.009, 1.574] and 1.410 [1.008, 2.038], respectively). There was no association between opium consumption and fatal and non-fatal MACCE in patients without SMuRF (HR = 1.027 [0.762-1.383], HR 0.700 [0.438-1.118]). Opium consumption was associated with earlier age of CABG in both groups; 2.77 (1.68, 3.85) years in SMuRF-less and 1.70 (1.11, 2.38) years in patients with SMuRFs.

Conclusion

Opium users not only undergo CABG at younger ages but also have a higher rate of mortality regardless of the presence of traditional CAD risk factors. Conversely, the risk of MACCE is only higher in patients with at least one modifiable CAD risk factor.

Association of Serum Pentraxin 3 and High-Sensitivity C-Reactive Protein with Severity of Coronary Stenosis

Background

Atherosclerosis being the keystone in the pathology of coronary artery disease (CAD) is a chronic inflammation of arterial intima mediated by various inflammatory markers. Pentraxin 3 (PTX3) and high-sensitivity C-reactive protein (hs-CRP) are the two important biomarkers of chronic inflammation that causes atherosclerosis.

Aims

This study aims to investigate the association of serum PTX3 and hs-CRP with the severity of coronary stenosis in patients undergoing coronary angiogram.

Subjects and Methods

A total of 80 patients who underwent elective coronary angiogram were included. Their blood sample was collected for PTX3 and hs-CRP estimation prior to angiogram. Based on the angiogram, the participants were divided into four groups based on the number of arteries affected. PTX3 was estimated using enzyme-linked immunosorbent assay and hs-CRP was assayed using latex-enhanced immunosorbent assay.

Statistical Analysis Used

Kruskal-Wallis test was used to find the association of PTX3 and hs-CRP in each group and Pearson's correlation was used to correlate PTX3 and hs-CRP with the extent of stenosis.

Results

The mean PTX3 and hs-CRP levels in patients with some lesions in the coronary artery were 231.5 ± 129.9 pg/mL and 2.4 ± 0.4 mg/mL, respectively. The PTX3 levels elevate gradually with the severity of stenosis with P = 0.000 which is highly significant. A strong positive correlation was observed (R = 0.7929, P < 0.00001) with PTX3 and severity of stenosis. Whereas, for hs-CRP, the correlation was weaker (R = 0.3011, P = 0.006).

Conclusions

PTX3 and hs-CRP can not only predict the number of arteries affected but also can differentiate between normal coronaries and CAD which can minimize the use of angiography.

Association between remnant lipoprotein cholesterol, high-sensitivity C-reactive protein, and risk of atherosclerotic cardiovascular disease events in the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Elevated remnant-lipoprotein (RLP)-cholesterol (RLP-C) and high-sensitivity C-reactive protein (hsCRP) are each individually associated with atherosclerotic cardiovascular disease (ASCVD).

OBJECTIVE

To evaluate the interplay of nuclear magnetic resonance (NMR)-derived RLP-C and hsCRP and their association with ASCVD in the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

Lipoprotein particles were measured using NMR spectroscopic analysis at baseline. RLP-C includes very-low-density lipoprotein cholesterol and intermediate-density lipoprotein cholesterol. Four groups were created as follows: Group 1: RLP-C ≤ median (≤29.14 mg/dL) and hsCRP < 2 mg/L; Group 2: RLP-C ≤ median and hsCRP≥ 2 mg/L; Group 3: RLP-C > median and hsCRP level < 2 mg/L; and Group 4: RLP-C > median and hsCRP level ≥ 2 mg/L. Kaplan-Meier survival curves and multivariable-adjusted Cox proportional hazard models were used to examine the relationship between RLP-C and hsCRP with incident ASCVD.

RESULTS

A total of 6,720 MESA participants (mean age 62.2 y, 53% female) with a median follow-up of 15.6 years were included. In the fully adjusted model, compared to those in the reference group (Group 1), participants in Group 2, Group 3, and Group 4 demonstrated a 20% (95% CI, -2%-48%), 18% (-4%-44%), and 43% (18%-76%) increased risk of incident ASCVD events, respectively (p < 0.01). An additive and multiplicative interaction between RLP-C and hsCRP was not statistically significant.

CONCLUSION

NMR-derived RLP-C and hsCRP showed a similar independent association with incident ASCVD. Notably, the combination of increased RLP-C and hsCRP was associated with an increased risk of future ASCVD events.

The Stockholm Study: Over 30 years’ Observation of the Effect of Oral Infections on Systemic Health

The Stockholm Studies are a series of investigations started in 1985 and still ongoing. Out of 105,798 inhabitants, aged 30 and 40 years and living in the greater Stockholm area in Sweden, 3273 subjects were randomly selected. Of them, 1676 were clinically examined focusing on oral health. The subjects were then followed up using national population and health registers in order to study associations between oral health parameters and systemic health outcomes and finally death. The 35 years of observation provides unique possibilities to analyze, for example, how periodontitis links to a number of systemic health issues. The results have consequently provided numerous new associations and confirmed earlier observations on how poor oral health is associated with heart diseases and cancer.

Does Pentraxin-3 contribute to the reduction of low-density lipoprotein levels by statin therapy?

Statins have been shown to decrease inflammatory markers, especially high sensitivity C reactive protein (hsCRP), in a dose-dependent manner. Pentraxin-3 (PTX3) is another important inflammatory biomarker from the pentraxin family that provides useful prognostic information and facilitates diagnostics of cardiovascular diseases. This study investigated the effect of statin therapy on PTX3 and hsCRP concentrations and whether statins acted synergistically with PTX3 and hsCRP concentrations in lowering LDL-C. The study group consisted of 90 patients undergoing coronary angiography. The results showed that statins reduced PTX3 concentrations (p=0.031). PTX3 and hsCRP levels were significantly different between subclinical and severe stenosis groups (p=0.011 and p=0.009, respectively). Statin therapy was significantly associated with lower PTX3 and LDL-C levels in multiple logistic analyses. The probability that statin therapy would achieve target LDL-C values was highest in patients with low PTX3 values (OR=3.683, p=0.040), while multiplicative interaction was 23.3. The effect of statins on PTX3 reduction was higher than on hsCRP. It can be suggested that statin therapy was more successful in patients with low PTX3 values.

Pathophysiology of Circulating Biomarkers and Relationship With Vascular Aging: A Review of the Literature From VascAgeNet Group on Circulating Biomarkers, European Cooperation in Science and Technology Action 18216

Impairment of the arteries is a product of sustained exposure to various deleterious factors and progresses with time; a phenomenon inherent to vascular aging. Oxidative stress, inflammation, the accumulation of harmful agents in high cardiovascular risk conditions, changes to the extracellular matrix, and/or alterations of the epigenetic modification of molecules, are all vital pathophysiological processes proven to contribute to vascular aging, and also lead to changes in levels of associated circulating molecules. Many of these molecules are consequently recognized as markers of vascular impairment and accelerated vascular aging in clinical and research settings, however, for these molecules to be classified as biomarkers of vascular aging, further criteria must be met. In this paper, we conducted a scoping literature review identifying thirty of the most important, and eight less important, biomarkers of vascular aging. Herein, we overview a selection of the most important molecules connected with the above-mentioned pathological conditions and study their usefulness as circulating biomarkers of vascular aging.

Purification of Recombinant Mouse C-Reactive Protein from Pichia Pastoris GS115 by Nickel Chelating Sepharose Fast-Flow Affinity Chromatography and P-Aminophenyl Phosphoryl Choline Agarose Resin Affinity Chromatography in Tandem

C-reactive protein (CRP) is a circulating marker of inflammation yet with ill-defined biological functions. This is partly due to the uncharacterized activities of endogenous CRP in mice, the major animal model used to define protein function. The hurdles for purification and characterization of mouse CRP are its low circulating levels and the lack of specific antibodies. To clear these hurdles, here we developed an efficient expression system by constructing recombinant Pichia pastoris cells for secretion of native conformation mouse CRP. The recombinant expression of mouse CRP in Escherichia coli failed to yield sufficient amount of native protein, reflecting the importance of post-translational modification of glycosylation in aiding proper folding. By contrast, sufficient amount of native mouse CRP was successfully purified from P. pastoris. Preliminary purification was performed by Nickel Chelating Sepharose Fast-Flow affinity chromatography with 6 × His tags attached to the protein. Subsequently, p-Aminophenyl Phosphoryl Choline Agarose resin affinity chromatography was used for tandem purification. The purified mouse CRP showed native pentamer and capabilities of PC binding. Moreover, the 6 × His tag provides a convenient tool for detecting the interactions of mouse CRP with ligands.

Thromboembolic and atherosclerotic cardiovascular events in inflammatory bowel disease: epidemiology, pathogenesis and clinical management

Inflammatory bowel disease (IBD) is associated with an increased risk of cardiovascular disease (CVD). The increased risk of CVD concerns an increased risk of venous thromboembolism (VTE), atherosclerotic cardiovascular disease (ASCVD) and heart failure (HF), at corresponding relative risks of 2.5, 1.2 and 2.0, respectively, as compared with the general population. Especially young patients under the age of 40 years run a relatively high risk of these complications when compared with the general population. Chronic systemic inflammation causes a hypercoagulable state leading to the prothrombotic tendency characteristic of VTE, and accelerates all stages involved during atherogenesis in ASCVD. Increased awareness of VTE risk is warranted in patients with extensive colonic disease in both ulcerative colitis and Crohn's disease, as well as during hospitalization, especially when patients are scheduled for surgery. Similarly, critical periods for ASCVD events are the 3 months prior to and 3 months after an IBD-related hospital admission. The increased ASCVD risk is not fully explained by an increased prevalence of traditional risk factors and includes pro-atherogenc lipid profiles with high levels of small dense low-density lipoprotein cholesterol particles and dysfunctional high-density lipoprotein cholesterol. Risk factors associated with HF are location and extent of inflammation, female sex, and age exceeding 40 years. A dose-dependent increase of overall CVD risk has been reported for corticosteroids. Immunomodulating maintenance therapy might reduce CVD risk in IBD, not only by a direct reduction of chronic systemic inflammation but possibly also by a direct effect of IBD medication on platelet aggregation, endothelial function and lipid and glucose metabolism. More data are needed to define these effects accurately. Despite accumulating evidence on the increased CVD risk in IBD, congruent recommendations to develop preventive strategies are lacking. This literature review provides an overview of current knowledge and identifies gaps in evidence regarding CVD risk in IBD, by discussing epidemiology, pathogenesis, and clinical management.

Effects of atorvastatin doses on serum level of procalcitonin and predictors for major adverse cardiovascular events in patients with acute myocardial infarction: a pilot study and post hoc analysis

BACKGROUND

Inflammation plays an important role in acute myocardial infarction (AMI). Procalcitonin levels rise in response to proinflammatory stimuli. This study aimed to investigate the effects of different doses of atorvastatin on the serum inflammatory profiles, especially procalcitonin and major adverse cardiovascular events (MACEs) in patients with AMI during hospitalization.

METHODS

The patients who were admitted to the Coronary Care Unit of The Third Medical Center of PLA General Hospital (Beijing, China) between January 2015 and December 2015 with a diagnosis of AMI were enrolled, and randomized to atorvastatin 20 mg/day postoperatively (20-mg group), 40 mg/day postoperatively (40-mg group) and 80 mg preoperatively+40 mg/day postoperatively (80/40-mg group). Serum procalcitonin and high-sensitivity C-reactive protein (hs-CRP) were evaluated before and at 1 and 3 days after percutaneous coronary intervention (PCI).

RESULTS

A total of 112 patients with AMI (23 women and 89 men) were prospectively eligible for the study. There were no significant differences in most clinical data among the three groups. The 80/40-mg group showed significantly reduced serum procalcitonin levels at 1 and 3 days after PCI (P < 0.001) and reduced hs-CRP levels at 3 days P = 0.001) compared with 20-mg and 40-mg groups. Serum procalcitonin (OR, 4.593; 95% CI, 1.476-8.387; P = 0.005), hs-CRP (OR, 1.149; 95% CI, 1.012-1.338; P = 0.018), highly sensitive cardiac troponin T (OR, 1.255; 95% CI, 1.004-1.569, P = 0.009) and Gensini score (OR, 1.022; 95% CI, 1.045-1.062; P = 0.013) were independently associated with MACEs during hospitalization.

CONCLUSION

The use of atorvastatin 80 mg before and 40 mg/day after PCI in patients with AMI can effectively reduce serum inflammatory factors. procalcitonin and hs-CRP were independently associated with in-hospital MACEs.

Omega-3 fatty acids ameliorate doxorubicin-induced cardiorenal toxicity: In-vivo regulation of oxidative stress, apoptosis and renal Nox4, and in-vitro preservation of the cytotoxic efficacy

This study examines the protective effects of omega-3 fatty acids (OMG), a frequently used nutritional therapy in cancer patients, against doxorubicin (DOX)-induced acute cardiorenal toxicity in rats, and evaluates the cytotoxic activity of DOX when used with OMG against breast cancer cell line. Five groups of rats were treated for 4 consecutive weeks with vehicle (groups I & II), or OMG (25, 50 or 100 mg/kg/day, po; groups III, IV & V, respectively). After twenty-four hours, the last four groups were injected with DOX (200 mg/kg, ip). In DOX-treated rats, the altered ECG, serum cardiac and renal function biomarkers, and histopathological features indicated the induction of cardiorenal toxicity. Increased oxidative and apoptotic markers in both organs was observed, with elevated renal contents of NADPH-oxidase-4 (Nox4) and renin. OMG pretreatment improved those DOX-induced impairments in a dose-dependent manner, and showed antioxidant and antiapoptotic effects with regulation of renal Nox4 expression. The in-vitro study showed preservation of the cytotoxic activity of DOX on MCF7 cell line in the presence of OMG. The data suggests OMG for protection against acute DOX-induced cardiorenal damage without affecting the latter antitumor activity. It proposes regulation of oxidative stress, Nox4 activity and apoptosis as contributing protective mechanisms.

Opium and cardiovascular health: A devil or an angel?

Opioids have the highest rate of illicit drug consumption after cannabis worldwide. Opium, after tobacco, is still the most commonly abused substance in the Middle East. In addition to the ease of availability, one reason for the high consumption of opium in Asian countries might be a traditional belief among Eastern people and even medical staff that opium may have ameliorating effects on cardiovascular diseases (CVDs) as well as diabetes mellitus, hypertension, and dyslipidemia. Over the last decade, many studies have been performed on humans and animals to evaluate the interplay between opium consumption and stable coronary artery disease, acute coronary syndromes, and atherosclerosis. In this review, we conclude that opium consumption should be considered a risk factor for CVDs. Healthy individuals, as well as cardiac and diabetic patients, should be informed and educated about the hazardous effects of opium consumption on cardiovascular and other chronic diseases.

effects of azide-containing human CRP isoforms and oxLDL on U937-derived macrophage production of atherosclerosis-related cytokines

Atherosclerosis is an inflammatory chronic disease of the arterial wall. Monomeric (m) and pentameric (p) C-reactive protein (CRP) and oxidized low density lipoproteins (oxLDL) seem to affect the pattern of cytokine production by macrophages, thus playing an important role in atherogenesis. Azide, the commercial preservative of CRP, may influence its action in vitro. The present study aimed to determine the effects of both isoforms of azide-containing CRP (mCRP and pCRP) with and without oxLDL on cytokine production by U937-derived macrophages. U937 monocytes were cultured and differentiated into macrophages and treated with mCRP, pCRP, oxLDL and azide individually and in combination. ELISA were performed to measure the levels of interferon-γ (IFN-γ), interleukin (IL)-4, IL-6, IL-10 and tumor necrosis factor (TNF)-α in culture supernatants collected from U937-derived macrophages following their respective treatments. Most single and combined treatments, especially in triple combination, were able to downregulate the levels of IFN-γ and IL-6 compared with control untreated cells, whilst the combination of mCRP and pCRP increased IL-4 levels. Regarding IL-10, except for an increase induced by mCRP, no significant effect was caused by any treatment compared with the control. On the other hand, the levels of TNF-α were not significantly affected by any treatment except for a decreasing trend that was observed with mCRP/oxLDL treatment compared with control. By contrast, double azide caused a significant decrease in the levels of IFN-γ and IL-6. The results of the present study indicated that mCRP, pCRP, oxLD and possibly azide, individually or in different combinations, had the tendency to upregulate the expression of IL-4 and to downregulate that of the pro-atherogenic cytokines, IFN-γ and IL-6, suggesting that the intima microenvironment serves a crucial role in atherogenesis.

C-Reactive Protein Promotes the Activation of Fibroblast-Like Synoviocytes From Patients With Rheumatoid Arthritis

Objective: To evaluate the biological effect and mechanisms of C-reactive protein (CRP) on the activation of fibroblast-like synoviocytes (FLSs) from patients with rheumatoid arthritis (RA).

Study design: To understand if CRP is involved in RA, expression of CRP and its receptors CD32/64 was examined in synovial tissues from RA patients and normal controls. In vitro, the potential role and mechanisms of CRP in FLS proliferation and invasion, expression of pro-inflammatory cytokines, and activation of signaling pathways were investigated in both RA - FLS and a normal human fibroblast-like synoviocyte line (HFLS).

Results: Compared to normal controls, synovial tissues from 21 RA patients exhibited highly activated CRP signaling, particularly by FLSs as identified by 65% of CRP-expressing cells being CRP+vimentin+ and CD32/64+vimentin+ cells. In vitro, FLSs from RA patients, but not HFLS, showed highly reactive to CRP by largely increasing proliferative and invasive activities and expressing pro-inflammatory cytokines and chemokines, including CCL2, CXCL8, IL-6, and MMP2/9. All these changes were blocked largely by a neutralizing antibody to CD32 and, to a less extent by the anti-CD64 antibody, revealing CD32 as a primary mechanism of CRP signaling during synovial inflammation. Further studies revealed that CRP also induced synovial inflammation differentially via CD32/CD64- NF-κB or p38 pathways as blockade of CRP-CD32-NF-κB signaling inhibited CXCL8, CCL2, IL-6, whereas CRP induced RA-FLS invasiveness through CD32-p38 and MMP9 expression via the CD64-p38-dependent mechanism.

Conclusions: CRP signaling is highly activated in synovial FLSs from patients with RA. CRP can induce synovial inflammation via mechanisms associated with activation of CD32/64-p38 and NF-κB signaling.

The Association Between Vascular Inflammation and Depressive Disorder. Causality, Biomarkers and Targeted Treatment

Diabetes, obesity, atherosclerosis, and myocardial infarction are frequently co-morbid with major depressive disorder. In the current review, it is argued that vascular inflammation is a factor that is common to all disorders and that an endothelial dysfunction of the blood-brain barrier could be involved in the induction of depression symptoms. Biomarkers for vascular inflammation include a high plasma level of C-reactive protein, soluble cell-adhesion molecules, von Willebrand factor, aldosterone, and proinflammatory cytokines like interleukin-6 or tumor necrosis factor α. A further possible biomarker is flow-mediated dilation of the brachial artery. Treatment of vascular inflammation is expected to prevent or to reduce symptoms of depression. Several tentative treatments for this form of depression can be envisioned: eicosapentaenoic acid (EPA), valproate, Vagus-nerve stimulation, nicotinic α7 agonists, and agonists of the cannabinoid CB₂-receptor.

Religiosity/Spirituality and Physiological Markers of Health

The long-standing interest in the effects of religiosity and spirituality (R/S) on health outcomes has given rise to a large and diverse literature. We conducted a meta-analysis on research involving R/S and physiological markers of health to elucidate both the scope and mechanism(s) of this phenomenon. A combined analysis found a significant, but small, beneficial effect. Subgroup analyses found that some measures of both extrinsic and intrinsic religiosity were significantly associated with health. Several outcome measures, including blood pressure, C-reactive protein, and cardiovascular health markers, were significantly associated with R/S. Our findings suggest that R/S benefits health, perhaps through minimizing the disruptive effects of stress/depression on inflammation. We hope that researchers can use these results to guide efforts aimed at elucidating the true mechanism(s) linking religious/spiritual beliefs and physical health.

Matrix sieving-enforced retrograde transcytosis regulates tissue accumulation of C-reactive protein

Aims

Circulating proteins larger than 3 nm can be transported across continuous endothelial barrier of blood vessels via transcytosis. However, excessive accumulation of serum proteins within the vessel walls is uncommon even for those abundant in the circulation. The aim of this study was to investigate how transcytosis regulates tissue accumulation of the prototypical acute-phase reactant C-reactive protein (CRP) and other serum proteins.

Methods and results

Transcytosis of CRP as well as of transferrin and low-density lipoprotein across aortic endothelial cells is bidirectional with directional preference from the apical (blood) to basolateral (tissue) direction both in vitro and in vivo. This directional preference is, however, reversed by the basement membrane (BM) matrix underlying the basolateral surface of endothelial cells. This is due to the sieving effect of the BM that physically hinders the diffusion of transcytosed proteins from the apical compartment towards underlying tissues, resulting in immediate retrograde transcytosis that limits basolateral protein accumulation. Conversely, CRP produced within vessel wall lesions can also be transported into the circulation.

Conclusion

Our findings identify matrix sieving-enforced retrograde transcytosis as a general mechanism that prevents excessive tissue accumulation of blood-borne proteins and suggest that lesion-derived CRP might also contribute to elevated serum CRP levels associated with increased risk for cardiovascular diseases.

Intra-subunit Disulfide Determines the Conversion and Structural Stability of CRP Isoforms

C-reactive protein (CRP) is a major human acute-phase reactant that is composed of five identical subunits. CRP dissociates into subunits at inflammatory loci forming monomeric CRP (mCRP) with substantially enhanced activities, which can be further activated by reducing the intra-subunit disulfide bond. However, conformational changes underlying the activation process of CRP are less well understood. Conformational changes accompanying the conversion of CRP to mCRP with or without reduction were examined with circular dichroism spectroscopy, fluorescence spectroscopy, electron microscopy, size-exclusion chromatography, and neoepitope expression. The conversion of CRP to mCRP follows a two-stage process. In the first stage, CRP dissociates into molten globular subunits characterized by intact secondary structure elements with greatly impaired tertiary packing. In the second stage, these intermediates completely lose their native subunit conformation and assemble into high-order aggregates. The inclusion of reductant accelerates the formation of molten globular subunits in the first step and promotes the formation of more compact aggregates in the second stage. We further show a significant contribution of electrostatic interactions to the stabilization of native CRP. The conformational features of dissociated subunits and the aggregation of mCRP may have a key impact on their activities.

The cardiotoxicity effect of different chemotherapeutic regimens in Iraqi patients with breast cancer: A follow up study

Introduction

Breast cancer is the first in ranking among cancers in Iraq. Anthracyclines, cyclophosphamide and taxane are the most active chemotherapeutic regimens used. Anthracyclines induced cardiotoxicity through free radical formation while there is no full understanding about that of cyclophosphamide, but it thought that it may cause direct cardiac muscle damage. While, taxane induced cardiotoxicity through coronary vasoconstriction and oxidative stress. Thus; it is very important to study changes in the cardiac biomarkers as they were the most reliable and sensitive markers associated with cardiotoxicity.

Aim

This research was designed to carry out investigations on the cardiotoxicity effects of these chemotherapeutic drugs in Iraqi patients with breast cancer.

Materials and methods

This research was performed at the Department of Biochemistry, Medicine College, Baghdad University and at the Oncology Department of the Teaching Hospital, Baghdad - Iraq, during the period from May 2018 to October 2018. It was carried out on 56 women with undisturbed menstrual cycle (25–45 years), These women were divided into 3 groups: GI was of 29 women with primary breast cancer without starting any kind of chemotherapy, GII: the same 29 women of GI after finishing 4 cycles of anthracyclines (course 1) and GIII: which involved another 27 women after finishing both course 1 and course 2 (4 cycles of taxanes). Investigations included serum measurements of high sensitive cardiac troponin (hs-cTn), NT-pro-brain natriuretic peptide (NT-ProBNP), and high sensitive- C reactive protein (hs-CRP) by using ELISA technique. The statistical analysis was performed using the Statistical Package for Social Sciences (SPSS) version 23, when the P-values were less than 0.05, it was considered as significant.

Results

The mean (±SEM) value of the serum hs-CRP levels was decreased significantly in GIII in comparison to both GI (p = 0.004) and GII (p = 0.049) while there was no significant difference between GI and GII. Also, there was no significant difference in the mean (±SEM) value of the serum hs-cTn and the serum NT-PROBNP levels between all groups. The results also showed that there was a significant negative correlation between BMI values and serum NT-proBNP levels in GI (r = −0.435, p = 0.018), GII (r = −0.438, p = 0.018), and GIII (r = −0.384, p = 0.048). In GI, there was also a significant positive correlation between BMI and serum hs-CRP levels (r = 0.395, p = 0.034). Also, there was a significant positive correlation between serum hs-cTn levels and NT-proBNP levels in GI (r = 0.416, p = 0.025) and GII (r = 0.467, p = 0.011). Moreover, there was a significant negative correlation between the serum hs-cTn levels and serum hs- CRP concentrations (r = −0.397, p = 0.040) in GIII.

Conclusion

This study had concluded insignificant changes of cardiac biochemical markers during the chemotherapeutic treatment and that chemotherapy-induced cardiotoxicity is negligible.

Functionality of C-Reactive Protein for Atheroprotection

C-reactive protein (CRP) is a pentameric molecule made up of identical monomers. CRP can be seen in three different forms: native pentameric CRP (native CRP), non-native pentameric CRP (non-native CRP), and monomeric CRP (mCRP). Both native and non-native CRP execute ligand-recognition functions for host defense. The fate of any pentameric CRP after binding to a ligand is dissociation into ligand-bound mCRP. If ligand-bound mCRP is proinflammatory, like free mCRP has been shown to be in vitro, then mCRP along with the bound ligand must be cleared from the site of inflammation. Once pentameric CRP is bound to atherogenic low-density lipoprotein (LDL), it reduces both formation of foam cells and proinflammatory effects of atherogenic LDL. A CRP mutant, that is non-native CRP, which readily binds to atherogenic LDL, has been found to be atheroprotective in a murine model of atherosclerosis. Thus, unlike statins, a drug that can lower only cholesterol levels but not CRP levels should be developed. Since non-native CRP has been shown to bind to all kinds of malformed proteins in general, it is possible that non-native CRP would be protective against all inflammatory states in which host proteins become pathogenic. If it is proven through experimentation employing transgenic mice that non-native CRP is beneficial for the host, then using a small-molecule compound to target CRP with the goal of changing the conformation of endogenous native CRP would be preferred over using recombinant non-native CRP as a biologic to treat diseases caused by pathogenic proteins such as oxidized LDL.

Uric acid: from a biological advantage to a potential danger. A focus on cardiovascular effects

Non-communicable diseases represent nowadays the most common cause of death worldwide, having largely overcome infectious diseases. Among them, cardiovascular diseases constitute the majority. Given these premise, great efforts have been made by scientific societies to emphasize the fundamental role of cardiovascular prevention and risk factors control. In addition to classical cardiovascular risk factors such as smoking, arterial hypertension, hypercholesterolemia and male gender, new risk factors are emerging from international literature. Among them, uric acid is the protagonist. Several evidences show a direct role of hyperuricemia in the determinism of metabolic and vascular disorders. From the other hand, some researchers have demonstrated that uric acid is only a marker of cardiovascular damage and not a risk factor for its development. Aim of this review is to evaluate the scientific evidences on the role of uric acid in cardiovascular diseases in order to shed light on this confusing topic.

Evolution of C-Reactive Protein

C-reactive protein (CRP) is an evolutionarily conserved protein. From arthropods to humans, CRP has been found in every organism where the presence of CRP has been sought. Human CRP is a pentamer made up of five identical subunits which binds to phosphocholine (PCh) in a Ca²⁺-dependent manner. In various species, we define a protein as CRP if it has any two of the following three characteristics: First, it is a cyclic oligomer of almost identical subunits of molecular weight 20–30 kDa. Second, it binds to PCh in a Ca²⁺-dependent manner. Third, it exhibits immunological cross-reactivity with human CRP. In the arthropod horseshoe crab, CRP is a constitutively expressed protein, while in humans, CRP is an acute phase plasma protein and a component of the acute phase response. As the nature of CRP gene expression evolved from a constitutively expressed protein in arthropods to an acute phase protein in humans, the definition of CRP became distinctive. In humans, CRP can be distinguished from other homologous proteins such as serum amyloid P, but this is not the case for most other vertebrates and invertebrates. Literature indicates that the binding ability of CRP to PCh is less relevant than its binding to other ligands. Human CRP displays structure-based ligand-binding specificities, but it is not known if that is true for invertebrate CRP. During evolution, changes in the intrachain disulfide and interchain disulfide bonds and changes in the glycosylation status of CRP may be responsible for different structure-function relationships of CRP in various species. More studies of invertebrate CRP are needed to understand the reasons behind such evolution of CRP. Also, CRP evolved as a component of and along with the development of the immune system. It is important to understand the biology of ancient CRP molecules because the knowledge could be useful for immunodeficient individuals.

Determination of CRP Autoantibodies by SPR Immunoassay

Biosensors based on the principle of surface plasmon resonance (SPR) are surface-sensitive optical devices used for monitoring biomolecular interactions at the sensor surface in real time without any labeling. It is used in a wide variety of areas including proteomics, clinical diagnosis, environmental monitoring, drug discovery, and food analysis. C-reactive protein (CRP) is a marker of inflammation, which undergoes conformation changes in local lesions, leading to the formation of mCRP. Autoantibodies against mCRP are frequently detected in systemic lupus erythematosus (SLE) and associated with disease activity and prognosis. An SPR immunoassay for CRP autoantibodies at complement factor H-CRP interface is described in this chapter.

Glycemic reduction alters white blood cell counts and inflammatory gene expression in diabetes

OBJECTIVE

Systemic inflammation contributes to cardiovascular disease in patients with type 2 diabetes, and elevated white blood cell (WBC) counts are an established risk factor. Our goal is to describe changes in WBCs and inflammatory markers after glycemic reductions in diabetes.

RESEARCH DESIGN AND METHODS

This study enrolled 63 subjects with poorly controlled diabetes, defined as hemoglobin A1c (HbA1c) ≥8% [64 mmol/mol]. Circulating granulocytes and mononuclear cells were separated by histopaque double-density protocol. Inflammatory markers from these isolated WBCs were assessed at baseline and after 3 months of medical management.

RESULTS

After 3 months, significant glycemic reduction, defined as a decrease in HbA1c ≥ 1.5%, occurred in 42 subjects. Fasting plasma glucose decreased by 47% (165.6 mg/dL), and HbA1c decreased from 10.2 ± 1.8 to 6.8 ± 0.9. Glycemic reductions were associated with a 9.4% decrease in total WBC counts, 10.96% decrease in neutrophils, and 21.74% decrease in monocytes. The mRNA levels of inflammatory markers from granulocytes and mononuclear cells decreased, including receptor for advanced glycation endproducts; S100 calcium binding proteins A8, A9, A12; krüppel-like factor 5; and IL-1. Also, circulating levels of IL-1β and C-reactive protein decreased. Insulin dose was a mediator between HbA1c and both total WBC and neutrophil counts, but not changes in WBC inflammatory markers. In contrast, the 17 subjects without significant glycemic reductions showed no significant differences in their WBC counts and proteins of inflammatory genes.

CONCLUSION

Significant glycemic reduction in subjects with poorly controlled diabetes led to reduced circulating WBC counts and inflammatory gene expression.

PCSK9: A novel inflammation modulator in atherosclerosis?

Proprotein convertase subtilisin/kexin 9 (PCSK9) is the ninth member of the secretory serine protease family. It binds to low-density lipoprotein receptor (LDLR) for endocytosis and lysosome degradation in the liver, resulting in an increasing in circulating LDL-cholesterol (LDL-c) level. Since a PCSK9 induced increase in plasma LDL-c contributes to atherosclerosis, PCSK9 inhibition has become a new strategy in preventing and treating atherosclerosis. However, in addition to the effect of PCSK9 on elevating blood LDL-c levels, accumulating evidence shows that PCSK9 plays an important role in inflammation, likely representing another major mechanism for PCSK9 to promote atherosclerosis. In this review, we discuss the association of PCSK9 and inflammation, and highlight the specific effects of PCSK9 on different vascular cellular components involved in the atherosclerotic inflammation. We also discuss the clinical evidence for the association between PCSK9 and inflammation in atherosclerotic cardiovascular disease. A better understanding of the direct association of PCSK9 with atherosclerotic inflammation might help establish a new role for PCSK9 in vascular biology and identify a novel molecular mechanism for PCSK9 therapy.

Is there a gender-specific association between asthma and carotid intima media thickness in Swiss adolescents?

Respiratory diseases are associated with increased cardiovascular risk in adults, but little is known on the early impact on the vasculature in youth. The SAPALDIA Youth study, the offspring study of the Swiss Study on Air Pollution and Lung and Heart Disease In Adults (SAPALDIA), investigated the association between physician-diagnosed asthma status and common carotid artery intima media thickness (CIMT). Offspring underwent standardized clinical protocols and provided information on early life factors, health, and lifestyle. The association between per subject averages of CIMT and asthma was estimated using mixed linear regression analyses adjusting for main confounders, testing for interaction with gender and age. Of 257 offspring (mean age 15 years, 53% female), 11.5% reported doctor-diagnosed asthma (male 17%, female 7%). Mean CIMT was significantly different by gender (male 0.53 mm (± 0.045), female 0.50 mm (± 0.048); p < 0.001). Interaction was highly significant by gender (p = 0.001) with significantly increased CIMT in asthmatic vs. non-asthmatics boys (difference 0.023 mm, 95% CI 0.003; 0.043), as compared to girls.

CONCLUSION

Our study suggests an increased risk for early vascular change in adolescent asthmatic boys. Whereas the small number of girls limits the interpretation, the result necessitates further research into sex-specific atherosclerotic burden related to respiratory health in adolescence. What is Known: • Evidence points to a significant impact of adult respiratory disease on cardiovascular health indicators as well as on endpoints. • Inflammation is a key pathway in vascular change across the life course. What is New: • We observe an adverse association between physician-diagnosed asthma and carotid intima media thickness in adolescent boys. • Albeit a limited number of asthmatic girls, we hypothesize the gender typical timing of asthma or a higher male cardiovascular vulnerability as possible explanations for the gender-specific results.

Correlation between immunological-inflammatory markers and endothelial disfunction in the early stage of coronary heart disease

Classical risk factors for endothelial dysfunction (ED), such as age, gender, total cholesterol, high-density lipoprotein cholesterol, systolic blood pressure, and smoking history are utilised for the Framingham score and Systemic Coronary Risk Estimation (SCORE) for evaluation of the 10-year cardiovascular risk in routine practice. Nonetheless, pro-inflammatory mediators are deeply involved in the initiation and the progression of ED and coronary artery disease (CAD), and act additionally or independently of metabolic factors before clinical manifestations of the disease appear. C-reactive protein, a marker of intimal thickening of the myeloid-related protein 8/14 heterodimer, monocyte chemotactic protein 1, interleukin-15, the cytotoxic mediator, granulysin, and the matrix metalloproteinase 9 could be valuable, single, fast, and non-invasive laboratory tools for ED deterioration degree assessment. We propose to investigate the impact of pro-inflammatory biomarkers on ED, measured by previously established clinical methods in patients with yet undiagnosed CAD and at medium risk for an acute coronary event. It could be useful to measure and correlate the concentration of particular inflammatory markers in peripheral blood samples and the results of the Framingham and SCORE charts, multi-slice computed tomography coronary angiography, echocardiography, brachial artery flow-mediated dilatation, carotid-femoral pulse wave velocity, ankle-brachial index, carotid wall thickening, myocardial perfusion scintigraphy, and particularly, cardiac magnetic resonance imaging. The goal would be that the degree of correlation between particular inflammatory markers and the results of some methods for the assessment of ED or cardiac ischaemic imaging could be emphasised and pro-inflammatory markers positioned in the pathogenetic algorithm of CAD.

The Apnea-Hypopnea Index Underestimates Systemic Inflammation in Women with Sleep-Disordered Breathing

BACKGROUND

Evidence suggests that sleep-related respiratory and related metabolic compromise may vary between females and males with sleep-disordered breathing (SDB). Our purpose was to elucidate possible gender differences in sleep-associated respiratory and inflammatory parameters in patients with SDB.

MATERIALS AND METHODS

A consecutive number of SDB patients (46 females and 167 males) who underwent polysomnography were retrospectively reviewed. Fibrinogen and C-reactive protein (CRP) concentration, apnea index (ApnI), hypopnea index (HypI), apnea-hypopnea index (AHI), average and minimal SpO₂, duration of snoring, age, and body mass index (BMI) were compared between sexes. Spearman's ρ correlation coefficients between parameters were also calculated.

RESULTS

ApnI and AHI were significantly higher in males. Correlation analysis revealed striking gender differences: only in females, CRP concentration was highly correlated with snoring duration (r = 0.4393), BMI (r = 0.7147), minimal SpO₂ (r = -0.4357), and average SpO₂ (r = -0.4547); in females, HypI was more strongly correlated with AHI (r = 0.8778), average SpO₂ (r = -0.5765), minimal SpO₂ (r = -0.5817), and fibrinogen concentration (r = 0.4614) than in males (r = 0.4373; -0.3295; -0.2969; and 0.0887, respectively); in females, age had a much more pronounced effect on ApnI, HypI, AHI, average oxygen saturation (SaO₂), minimal SaO₂, snoring duration, and CRP and fibrinogen concentration.

CONCLUSIONS

Respiratory compromise in females with SDB is more strongly associated with systemic inflammation than in males with SDB. Although females display a pathological AHI less frequently than males, they reach quite similar pathological SaO₂, CRP, and fibrinogen values. Therefore, AHI may underestimate the pathophysiological systemic effects of SDB in females.

An ELISA Assay for Quantifying Monomeric C-Reactive Protein in Plasma

Native C-reactive protein (nCRP) is a non-specific marker of inflammation being claimed as a bystander in several chronic disorders. Accumulating evidence indicates that nCRP dissociates to and acts primarily as the monomeric conformation (mCRP) at inflammatory loci. This suggests that mCRP may be a superior disease marker with improved specificity and clear causality to the underlying pathogenesis. However, the lack of a feasible assay to quantify mCRP in clinical samples precludes the assessment of that suggestion. Here we report the development of a sandwich ELISA assay for quantification of plasma mCRP using commercially available reagents. Our assay is reproducible and highly conformation-specific showing a reliable detection limit of 1 ng/mL. We further show that mCRP appears to be a better marker than nCRP in several skin-related autoimmune disorders. This assay thus provides a useful tool to examine the clinical significance and utility of mCRP.

Monomeric C-Reactive Protein Binds and Neutralizes Receptor Activator of NF-κB Ligand-Induced Osteoclast Differentiation

C-reactive protein (CRP) is an established marker of rheumatoid arthritis (RA) but with ill-defined actions in the pathogenesis. Here, we show that CRP regulates the differentiation of osteoclasts, a central mediator of joint inflammation and bone erosion in RA, in a conformation- and receptor activator of NF-κB ligand (RANKL)-dependent manner. CRP in the native conformation is ineffective, whereas the monomeric conformation (mCRP) actively modulates osteoclast differentiation through NF-κB and phospholipase C signaling. Moreover, mCRP can bind RANKL, the major driver of osteoclast differentiation, and abrogate its activities. The binding and inhibition of RANKL are mediated by the cholesterol binding sequence (CBS) of mCRP. Corroborating the in vitro results, CRP knockout exacerbates LPS-induced bone resorption in mice. These results suggest that mCRP may be protective in joint inflammation by inhibiting pathological osteoclast differentiation and that the CBS peptide could be exploited as a potential RANKL inhibitor.

Impaired arterial responsiveness in untreated gout patients compared with healthy non-gout controls: association with serum urate and C-reactive protein

To determine whether arterial responsiveness is impaired among patients with gout, and whether arterial responsiveness inversely correlates with serum urate and inflammatory measures. This is a cross-sectional study of untreated gout subjects (n = 34) and non-gout healthy controls (n = 64). High-resolution dynamic ultrasound-measured flow-mediated dilation (FMD) and nitroglycerin-mediated dilation (NMD) assessed endothelium-dependent and endothelium-independent arterial responsiveness respectively. Serum urate (sUA) and high-sensitivity C-reactive protein (hsCRP) were measured in the gout group, and correlated with FMD and NMD responses. Both FMD (2.20 ± 0.53 vs 3.56 ± 0.31, p = 0.021) and NMD (16.69 ± 1.54 vs 24.51 ± 0.90, p = 0.00002) were impaired in the gout versus control group. Stratification for individual comorbidities suggested that no single risk factor accounted for impaired FMD/NMD in the gout subjects. However, the degree of association between gout and FMD, but not NMD impairment, was dampened after multivariable adjustment (FMD unadjusted beta = - 1.36 (SE 0.58), p = 0.02; adjusted beta = - 1.16 (SE 0.78), p = 0.14 and NMD unadjusted beta = - 7.68 (SE 1.78), p < 0.0001; adjusted beta = - 5.33 (SE 2.46), p = 0.03). Within the gout group, there was an inverse correlation between FMD and sUA (R = - 0.5, p = 0.003), and between FMD and hsCRP (R = - 0.42, p = 0.017), but not between NMD and sUA or hsCRP. Compared with healthy controls, subjects with gout have reduced arterial function. Individual comorbidities are insufficient to account for differences between gout and control groups, but multiple comorbidities may collectively contribute to impairment in endothelium-dependent arterial responsiveness. Endothelial impairment is also related to sUA and hsCRP, markers of gout severity and inflammation respectively. Studies to determine whether gout therapy may improve arterial responsiveness are warranted.

Specific binding of human C-reactive protein towards supported monolayers of binary and engineered phospholipids

Circulating C-reactive protein (CRP) recognizes altered plasma membranes and activates complements systems in the acute phase of inflammation and infection in human. We have shown previously the calcium-independent adsorption of CRP toward 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and lysophosphatidylcholine (LPC) on supported phospholipid monolayers. Here, we extended our study to other phospholipids and additives to elucidate the pattern recognition of CRP using a surface plasmon resonance biosensor. Surface density and lateral fluidity depended on the type of phospholipids in the monolayers as characterized by SPR and fluorescence recovery after photobleaching measurements. CRP recognized 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-l-serine (POPS) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (POPG) in the supported POPC monolayers without calcium at pH 7.4 and 5.5. As opposed to LPC, CRP did not recognize 3-sn-lysophosphatidylethanolamine in the POPC monolayers in calcium-free conditions. While, the addition of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) or sphingomyelin to supported POPC monolayers blocked CRP adsorption. Calcium-dependent CRP binding was observed only at pH 5.5 on supported monolayers of engineered phospholipids with inverted headgroups relative to POPC. The complement 1q (C1q) protein recognized the active form of CRP on the supported phospholipid monolayers. The discovery of CRP recognition with these phospholipids aids our understanding of the activation dynamics of CRP with phospholipid-based biomaterials when used during the acute phase.

Stiff Substrates Increase Inflammation-Induced Endothelial Monolayer Tension and Permeability

Arterial stiffness and inflammation are associated with atherosclerosis, and each have individually been shown to increase endothelial monolayer tension and permeability. The objective of this study was to determine if substrate stiffness enhanced endothelial monolayer tension and permeability in response to inflammatory cytokines. Porcine aortic endothelial cells were cultured at confluence on polyacrylamide gels of varying stiffness and treated with either tumor necrosis factor-α (TNFα) or thrombin. Monolayer tension was measured through vinculin localization at the cell membrane, traction force microscopy, and phosphorylated myosin light chain quantity and actin fiber colocalization. Cell permeability was measured by cell-cell junction confocal microscopy and a dextran permeability assay. When treated with TNFα or thrombin, endothelial monolayers on stiffer substrates showed increased traction forces, vinculin at the cell membrane, and vinculin phosphorylation, suggesting elevated monolayer tension. Interestingly, VE-cadherin shifted toward a smaller molecular weight in endothelial monolayers on softer substrates, which may relate to increased VE-cadherin endocytosis and degradation. Phosphorylated myosin light chain colocalization with actin stress fibers increased in endothelial monolayers treated with TNFα or thrombin on stiffer substrates, indicating elevated cell monolayer contractility. Endothelial monolayers also developed focal adherens intercellular junctions and became more permeable when cultured on stiffer substrates in the presence of the inflammatory cytokines. Whereas each of these effects was likely mitigated by Rho/ROCK, Rho/ROCK pathway inhibition via Y27632 disrupted cell-cell junction morphology, showing that cell contractility is required to maintain adherens junction integrity. These data suggest that stiff substrates change intercellular junction protein localization and degradation, which may counteract the inflammation-induced increase in endothelial monolayer tension and thereby moderate inflammation-induced junction loss and associated endothelial monolayer permeability on stiffer substrates.

IL6R haplotype rs4845625*T/rs4537545*C is a risk factor for simultaneously high CRP, LDL and ApoB levels

Interleukin 6 receptor (IL-6R), mediating IL-6's biological functions, plays an important role in different diseases such as diabetes, obesity and cardio-vascular diseases. In this study, we investigated the effects of two single nucleotide polymorphisms (SNPs), within the IL-6R loci, previously associated with C-reactive protein (CRP) and coronary heart diseases risk, and with controversial effects on lipids traits: SNP rs4845625 and SNP rs4537545. The results showed that both investigated SNPs were antagonistically related with CRP levels; the minor rs4845625*T allele was associated with increased CRP levels (P-value=0.011), while the minor rs4537545*T allele was associated with decreased CRP levels (P-value=0.009). Interestingly, the minor rs4845625*T allele was significantly associated with higher low-density lipoprotein cholesterol (LDL-C) and ApoB levels (P=0.007 and P=0.009 respectively). Haplotype analysis showed that the TC haplotype, having the minor rs4845625*T allele, was related simultaneously with increased levels of CRP, LDL-C and ApoB levels, thus could be considered as a risk factor. Our investigation detects for the first time an independent effect of rs4845625 on LDL-C and ApoB traits, explaining an important range of those traits variability (3.49 and 5.57% respectively). Our findings might be of high clinical significance in pharmacogenomics studies of tocilizumab for which IL-6R is target.

Autoantibodies against C-Reactive Protein Influence Complement Activation and Clinical Course in Lupus Nephritis

Autoantibodies against the major acute-phase reactant C-reactive protein (CRP) are frequently found in patients with lupus nephritis. Further defining the autoimmune epitopes on CRP may not only improve patient stratification but also, hint at mechanisms of CRP action. Herein, we show that amino acids 35-47 constitute the major epitope recognized by anti-CRP autoantibodies in patients with lupus nephritis. Notably, the presence of autoantibodies against amino acids 35-47 associated with more severe renal damage and predicted worse outcome. This epitope is exposed on CRP only after irreversible structure changes, yielding a conformationally altered form termed modified or monomeric CRP (mCRP). ELISA and surface plasmon resonance assays showed that amino acids 35-47 mediate the interaction of mCRP with complement factor H, an inhibitor of alternative pathway activation, and this interaction greatly enhanced the in vitro cofactor activity of complement factor H. In contrast, autoantibodies against amino acids 35-47 inhibited these actions of mCRP. Our results thus provide evidence for the in vivo generation of mCRP in a human disease and suggest that mCRP actively controls the pathogenesis of lupus nephritis by regulating complement activation. Therefore, amino acids 35-47 constitute a functional autoimmune epitope on CRP that can be targeted therapeutically and diagnostically.

Coronary Artery Bypass Graft Surgery Outcomes Following 6.5 Years: A Nested Case-control Study

Background:

Coronary artery disease (CAD) is the leading causes of mortality and morbidity in worldwide. This nested case–control study investigated the predictors of death in long-term follow-up after coronary artery bypass graft surgery (CABG).

Methods:

Cases were defined as CABG patients who died in the period of May 2006–March 2013. Controls were CABG patients who were alive in the same period. Cases and controls were derived from an existing cohort, Tehran Heart Center-Coronary Outcome Measurement. One hundred and fifty-nine patients in control group were randomly selected from 566 available patients in follow-up database. A series of simple and multiple logistic regressions was performed in the context of univariate and multivariate analyses, respectively, for computing unadjusted and adjusted odds ratios and their confidence intervals (CI). In the univariate analyses, demographic or cardiometabolic factors were entered separately, and for multivariate analysis, we got both significant risk factors from univariate analysis and the major risk factors.

Results:

The results of multivariate analyses showed that for age, the likelihood of mortality increases in CABG patients (95%CI: 1.1; 1.03–1.2; P < 0.005). Other significant independent risk factors were peripheral vascular disease (PVD) (95%CI: 2.7; 1.06–6.8; P = 0.036), diabetics (95%CI: 2.49; 0.9–6.3; P = 0.039), smoking (95%CI: 4.38; 1.45–13.7; P = 0.011), length of stay in hospital after CABG surgery (95%CI: 1.14; 1.0–1.24; P = 0.001), total cholesterol (95%CI: 1.12; 1–1.2; P = 0.001), and C-reactive protein (CRP) (95%CI: 1.12; 0.99–1.27; P = 0.049) (all P < 0.05).

Conclusions:

The study results indicated that age, diabetes, cigarette smoking, PVD, long length of stay in hospital, elevated triglycerides, total cholesterol, CRP, and high-density lipoprotein cholesterol were significant contributing to increased mortality after CABG. It seems that vulnerable older patients continue to be at high risk with poor outcomes.

Pathway-Driven Approaches of Interaction between Oxidative Balance and Genetic Polymorphism on Metabolic Syndrome

Despite evidences of association between basic redox biology and metabolic syndrome (MetS), few studies have evaluated indices that account for multiple oxidative effectors for MetS. Oxidative balance score (OBS) has indicated the role of oxidative stress in chronic disease pathophysiology. In this study, we evaluated OBS as an oxidative balance indicator for estimating risk of MetS with 6414 study participants. OBS is a multiple exogenous factor score for development of disease; therefore, we investigated interplay between oxidative balance and genetic variation for development of MetS focusing on biological pathways by using gene-set-enrichment analysis. As a result, participants in the highest quartile of OBS were less likely to be at risk for MetS than those in the lowest quartile. In addition, persons in the highest quartile of OBS had the lowest level of inflammatory markers including C-reactive protein and WBC. With GWAS-based pathway analysis, we found that VEGF signaling pathway, glutathione metabolism, and Rac-1 pathway were significantly enriched biological pathways involved with OBS on MetS. These findings suggested that mechanism of angiogenesis, oxidative stress, and inflammation can be involved in interaction between OBS and genetic variation on risk of MetS.

Postprandial lipemic and inflammatory responses to high-fat meals: a review of the roles of acute and chronic exercise

Postprandial lipemia is an independent risk factor for development of cardiovascular disease. Postprandial inflammation following the prolonged elevation of triglycerides occurring subsequent to ingestion of high-fat meals, provides a likely explanation for increased disease risk. Substantial evidence has shown that acute exercise is an effective modality for attenuation of postprandial lipemia following a high-fat meal. However, much of the evidence pertaining to exercise intensity, duration, and overall energy expenditure for reducing postprandial lipemia is inconsistent. The effects of these different exercise variables on postprandial inflammation is largely unknown. Long-term, frequent exercise, however, appears to effectively reduce systemic inflammation, especially in at-risk or diseased individuals. With regard to an acute postprandial response, without a recent bout of exercise, high levels of chronic exercise do not appear to reduce postprandial lipemia. This review summarizes the current literature on postprandial and inflammatory responses to high-fat meals, and the roles that both acute and chronic exercise play. This review may be valuable for health professionals who wish to provide evidence-based, pragmatic advice for reducing postprandial lipemia and cardiovascular disease risk for their patients. A brief review of proposed mechanisms explaining how high-fat meals may result in pro-inflammatory and pro-atherosclerotic environments is also included.

Enhanced pro-protein convertase subtilisin/kexin type 9 expression by C-reactive protein through p38MAPK-HNF1α pathway in HepG2 cells

Plasma C‐reactive protein (CRP) concentration is associated positively with cardiovascular risk, including dyslipidemia. We suggested a regulating role of CRP on pro‐protein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of low‐density lipoprotein (LDL) metabolism, and demonstrated the PCSK9 as a pathway linking CRP and LDL regulation. Firstly, experiments were carried out in the presence of human CRP on the protein and mRNA expression of PCSK9 and LDL receptor (LDLR) in human hepatoma cell line HepG2 cells. Treatment with CRP (10 μg/ml) enhanced significantly the mRNA and protein expression of PCSK9 and suppressed the expression of LDLR. Of note, a late return of LDLR mRNA levels occurred at 12 hrs, while the LDLR protein continued to decrease at 24 hrs, suggesting that the late decrease in LDLR protein levels was unlikely to be accounted for the decrease in LDL mRNA. Secondly, the role of PCSK9 in CRP‐induced LDLR decrease and the underlying pathways were investigated. As a result, the inhibition of PCSK9 expression by small interfering RNA (siRNA) returned partly the level of LDLR protein and LDL uptake during CRP treatment; CRP‐induced PCSK9 increase was inhibited by the p38MAPK inhibitor, SB203580, resulting in a significant rescue of LDLR protein expression and LDL uptake; the pathway was involved in hepatocyte nuclear factor 1α (HNF1α) but not sterol responsive element‐binding proteins (SREBPs) preceded by the phosphorylation of p38MAPK. These findings indicated that CRP increased PCSK9 expression by activating p38MAPK‐HNF1α pathway, with a certain downstream impairment in LDL metabolism in HepG2 cells.

Development of a high sensitivity C-reactive protein immunoassay and comparison with a commercial kit

C-reactive protein (CRP) is intricately sensitive marker of inflammation, infection, and tissue damage. Role in the prognosis of heart diseases has been recently discovered. This study aimed to develop a cost-effective and high-sensitivity CRP immunoassay for use in cardiac risk assessment. Assay was optimized for coating, blocking of capturing antibody, dilution, and reaction time of the conjugate and sample volume. For normal reference range, CRP was determined in serum samples from apparently healthy volunteers. For clinical validation, CRP was determined in samples of acute coronary syndrome patients by in-house and commercial assays. The lower detection limit of in-house assay was 0.16 µg/L. Intra and inter assay imprecision was 4.39%, 4.6% and 8.6%, 9.3%, respectively. The correlation between the CRP levels by the two assays was r = 0.861. Sensitivity, specificity, predictive value for a positive test, and a negative test of in-house assay was 95.3%, 92.8%, 95.3%, and 92.8%, respectively. At lower-end CRP levels of both kits correlated very well but showed variation at upper end. In-house assay showed high sensitivity and reliability at lower end and it is hoped that will help to evaluate cardiac risk assessment (after improvement at upper end) in clinically poor settings.

Patients with an Inflamed Atherosclerotic Plaque have Increased Levels of Circulating Inflammatory Markers

Aim: Inflammation is highlighted in the pathogenesis and destabilization of atherosclerotic lesions. Noninvasive identification of inflammation of atherosclerotic lesions has been challenging. 18-Fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) is a useful technique for detecting inflamed atherosclerotic plaques in vivo. However, it is time consuming, expensive, and accompanied by radiation. Therefore, we investigated the relationship between levels of circulating inflammatory markers and the degree of inflammation of atherosclerotic plaques shown by 18F-FDG uptake. We aimed to identify high-risk patients with inflamed, unstable atherosclerotic plaques on the basis of the determination of inflammatory markers.

Methods: The study included 37 patients, 21 with high-grade stenosis of internal carotid artery (ICA group) and 16 with occlusion of common femoral artery (CFA group), who underwent endarterectomy. Mean age of the study population was 69.43 ± 6.2 years. Eight out of 21 patients with ICA stenosis and all patients with CFA occlusion were symptomatic. In all patients before endarterectomy, 18F-FDG-PET imaging was performed and blood samples were obtained for determination of circulating inflammatory markers: high-sensitivity C-reactive protein (hsCRP), tumor necrosis factor alpha (TNF-α), interleukins, and selectins. Both groups were compared with a sex- and age-matched control group composed of 27 healthy volunteers.

Results: 18F-FDG uptake, calculated by target-to-background ratio (TBR) was not significantly different between the groups. Levels of inflammatory markers were elevated, and there were no significant differences between ICA and CFA groups, with an exception of interleukin 6 (IL-6) levels, which was higher in the ICA group (3.2 ± 2.5 ng/L vs. 1.8 ± 1.3 ng/L, p < 0.05). There was a positive interrelationship between 18F-FDG-PET and most of the systemic inflammatory markers: hsCRP (r = 0.417, p = 0.010), IL-6 (r = 0.603, p < 0.001), and TNF-α (r = 0.374, p = 0.023). However, correlation between 18F-FDG-PET and P-selectin, E-selectin, and t-PA was not found.

Conclusion: Our study showed that an interrelationship exists between the intensity of inflammatory process of atherosclerotic lesions shown by FDG uptake and circulating inflammatory markers. Therefore, the determination of circulating inflammatory markers can have a potential to identify individuals with unstable, inflamed atherosclerotic plaques.

Systemic inflammation in patients with compromised upper airway anatomy and primary snoring or mild obstructive sleep apnea

Our aim was to study associations between serum fibrinogen and C-reactive protein (CRP) levels and respiratory parameters on polysomnography (PSG) in patients with snoring as their main complaint and compromised upper airway anatomy. In this retrospective study, consecutive patients (43 female and 132 male; age range 11-82 years, respiratory distress index-RDI range 0.1-94.4/h) with snoring as their main complaint and compromised upper airway anatomy who underwent PSG were assessed. Spearman's Rho coefficients between RDI, AI (apnea index), hypopnea index (HI), average and lowest SpO2 (in %) and CRP- and fibrinogen serum levels were calculated. Comparisons between groups were made using Wilcoxon-W test. Patients with CRP > 5 mg/dl (22 % of the cohort) had significantly increased RDI, AI, average and lowest SpO2 than patients with CRP < 5 mg/dl. Increased correlation coefficients were observed for average SpO2 (-0.386), RDI (0.355), lowest SpO2 (-0.323) and AI (0.309). Patients with fibrinogen >350 mg/dl (in 33 %) had significantly increased RDI, HI, AI, average and lowest SpO2 than patients with fibrinogen <350 mg/dl. Increased correlation coefficients were found for average (-0.340) and lowest (-0.268) SpO2, RDI (0.236) and AI (0.229). Even patients with RDI < 15/h had increased serum CRP-(in 11 %) and/or fibrinogen-(in 19 %) levels. Simultaneous elevation of both CRP and fibrinogen levels occurred only in patients with RDI > 5/h. Systemic inflammation is strongly associated with average and lowest SpO2, RDI and AI (and with HI) in snorers with compromised upper airway anatomy and is present even in patients with primary snoring and mild obstructive sleep apnea.

An Intrinsically Disordered Motif Mediates Diverse Actions of Monomeric C-reactive Protein

Most proinflammatory actions of C-reactive protein (CRP) are only expressed following dissociation of its native pentameric assembly into monomeric form (mCRP). However, little is known about what underlies the greatly enhanced activities of mCRP. Here we show that a single sequence motif, i.e. cholesterol binding sequence (CBS; a.a. 35-47), is responsible for mediating the interactions of mCRP with diverse ligands. The binding of mCRP to lipoprotein component ApoB, to complement component C1q, to extracellular matrix components fibronectin and collagen, to blood coagulation component fibrinogen, and to membrane lipid component cholesterol, are all found to be markedly inhibited by the synthetic CBS peptide but not by other CRP sequences tested. Likewise, mutating CBS in mCRP also greatly impairs these interactions. Functional experiments further reveal that CBS peptide significantly reduces the effects of mCRP on activation of endothelial cells in vitro and on acute induction of IL-6 in mice. The potency and specificity of CBS are critically determined by the N-terminal residues Cys-36, Leu-37, and His-38; while the versatility of CBS appears to originate from its intrinsically disordered conformation polymorphism. Together, these data unexpectedly identify CBS as the major recognition site of mCRP and suggest that this motif may be exploited to tune the proinflammatory actions of mCRP.

Undercarboxylated osteocalcin as a biomarker of subclinical atherosclerosis in non-dialysis patients with chronic kidney disease

BACKGROUND

Studies in recent years have shown that undercarboxylated osteocalcin (uOC) not only maintains bone mineralization, but is also involved in the regulation of atherosclerosis. However, a correlation between uOC and carotid atherosclerosis in non-dialysis patients with chronic kidney disease (CKD) has not been investigated. A total of 240 non-dialysis patients with CKD were included in the study. For these patients, the median estimated glomerular filtration rate (eGFR) was 20.05 (12.43-49.32) ml/min/1.73m(2). Serum uOC levels were measured using enzyme-linked immunosorbent assay (ELISA). Carotid ultrasonography was performed to assess carotid atherosclerotic plaques and intima-media thickness (IMT) in an attempt to analyze the relationship between uOC level and carotid atherosclerosis.

RESULTS

The uOC levels of non-dialysis patients with CKD were significantly lower than those of healthy controls [28.16 (21.40-45.85) ng/mL vs. 36.42 (28.05-49.28) ng/mL, P < 0.01]. The uOC levels gradually decreased as CKD progressed (P < 0.01). The uOC levels were significantly lower in patients with carotid plaques than in patients without carotid plaques [25.98 (20.14-31.35) ng/mL vs. 31.02 (25.86-36.40) ng/mL, P < 0.01]. uOC level showed significant negative correlation with IMT (r = -0.33, P < 0.01). Logistic regression analysis revealed that after adjustment for various confounding factors, decreased uOC levels were shown to indicate increased possibility of carotid atherosclerotic plaque development in non-dialysis patients with CKD (on every 1 SD decrease in the uOC level, odds ratio 1.70, 95 % confidence interval 1.24-2.98, P < 0.01). Multivariate stepwise regression analysis demonstrated that decreased uOC level (β = -0.163, P < 0.05) was an independent risk factor for increased carotid IMT in non-dialysis patients with CKD.

CONCLUSION

Serum uOC levels in non-dialysis patients with CKD are significantly lower than those in healthy individuals, and uOC is closely associated with subclinical atherosclerosis in CKD patients.

Targeting C-Reactive Protein in Inflammatory Disease by Preventing Conformational Changes

C-reactive protein (CRP) is a pentraxin that has long been employed as a marker of inflammation in clinical practice. Recent findings brought up the idea of CRP to be not only a systemic marker but also a mediator of inflammation. New studies focused on structural changes of the plasma protein, revealing the existence of two distinct protein conformations associated with opposed inflammatory properties. Native, pentameric CRP (pCRP) is considered to be the circulating precursor form of monomeric CRP (mCRP) that has been identified to be strongly proinflammatory. Recently, a dissociation mechanism of pCRP has been identified on activated platelets and activated/apoptotic cells associated with the amplification of the proinflammatory potential. Correspondingly, CRP deposits found in inflamed tissues have been identified to exhibit the monomeric conformation by using conformation-specific antibodies. Here we review the current literature on the causal role of the dissociation mechanism of pCRP and the genesis of mCRP for the amplification of the proinflammatory potential in inflammatory reactions such as atherosclerosis and ischemia/reperfusion injury. The chance to prevent the formation of proinflammatory mediators in ubiquitous inflammatory cascades has pushed therapeutic strategies by targeting pCRP dissociation in inflammation. In this respect, the development of clinically applicable derivatives of the palindromic compound 1,6-bis(phosphocholine)-hexane (1,6-bis PC) should be a major focus of future CRP research.