The biology, utilization, and attenuation of C-reactive protein in cardiovascular disease: part II

The traditional Chinese medicine formula Fufang-Zhenzhu-Tiaozhi protects myocardia from injury in diabetic minipigs with coronary heart disease

BACKGROUND AND PURPOSE

Diabetes mellitus (DM) is a major risk factor for coronary heart disease (CHD). Previous research has reported that the Fufang-Zhenzhu-Tiaozhi (FTZ) formula has obvious effects on the treatment of dyslipidemia and hyperglycemia. In the present study, we intended to establish a convenient DM-CHD model in minipigs and investigated the protective effect of FTZ against myocardial injury and its mechanism.

METHODS

The DM-CHD model was established by a high-fat/high-sucrose/high-cholesterol diet (HFSCD) combined with balloon injury in the coronary artery. Subsequently, sixteen Wuzhishan minipigs were assigned to three groups: control group, model group, and FTZ group. The model group and FTZ group were given a HFSCD, while the control group was given a normal diet (ND). FTZ was given with meals in the FTZ group. During this time, biochemical parameters, such as total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein (HDL-C), and fasting blood glucose (FBG), were measured by using testing kits. Insulin (INS) was determined by ELISA, and the homeostasis model assessment index of insulin resistance (HOMA-IR) was calculated to evaluate insulin resistance levels. After FTZ administration, the plasma levels of lactate dehydrogenase (LDH), creatine kinase isoenzyme MB (CK-MB), and cardiac troponin I (cTnI) were measured by using ELISA kits to evaluate myocardial injury. Coronary artery stenosis was analyzed by angiographic and HE staining. Myocardial ischemia was assayed with electrocardiogram (ECG). Moreover, cytokines, including interleukin-6 (IL-6), hypersensitive C-reactive protein (hs-CRP), and tumor necrosis factor-alpha (TNF-α), were measured by ELISA kits to assess inflammation. The myocardial tissue was collected, and the pathological morphology was observed by transmission electron microscopy (TEM), HE staining, and Masson staining. Western blots were used to detect the expression of PI3K, AKT, p-AKT, p-NF-κB, and NF-κB.

RESULTS

A DM-CHD model in minipigs with glucose-lipid metabolism disorder, coronary artery incrassation and myocardial damage was successfully established through balloon injury in the coronary artery combined with HFSCD. FTZ effectively inhibited coronary artery incrassation and protected the myocardium against injury in DM-CHD minipigs. FTZ decreased proinflammatory cytokine levels and upregulated the protein expression of the PI3K/Akt pathway in the myocardium.

CONCLUSIONS

A novel DM-CHD model in minipigs was successfully established through balloon injury in the coronary artery combined with HFSCD. FTZ has a protective effect against myocardial injury in DM-CHD by inhibiting inflammation and activating the PI3K/AKT signaling pathway.

Inflammation and coronary artery disease: from pathophysiology to Canakinumab Anti-Inflammatory Thrombosis Outcomes Study (CANTOS)

The worldwide prevalence of cardiovascular disease in general and atherosclerotic coronary artery disease in particular is a health and economic concern of unparalleled proportion. Despite a long history of astute observations beginning in 1575 made by Fallopius, followed by those of von Rokatansky, Virchow, Osler, and Ross, and incremental knowledge of the pathobiology of atherosclerosis to include varying stages of inflammation, response to internally and externally mediated vascular injury, and impaired homeostasis, gaps in the field's understanding persist. Here, we summarize the current scope of the problem for coronary artery disease, emerging constructs in its pathobiology and common clinical phenotypes, potentially useful biomarkers, clinical trials designed specifically to test the 'inflammation hypothesis' of disease, and the interface of pathobiology and precision medicine as a foundation for diagnosis, management, and future advances in the diagnosis, prognosis, natural history, prevention, and optimal management.

Article Commentary: Serum C-Reactive Protein (CRP), Target for Therapy or Trouble?

High sensitivity serum C-reactive protein (hs-CRP) has come into clinical use as a marker of risk for cardiovascular disease (CVD). In addition to a role as a marker of disease, CRP has also been implicated in the pathogenesis of CVD. Specific small-molecule inhibitors of CRP have recently been developed with the intent of mitigating cardiac damage during acute myocardial infarction. However, the use of CRP, both as a risk marker and a disease target are controversial for several reasons. Serum hs-CRP concentrations can be elevated on the basis of genetics, female gender, and non-Caucasian ethnicity. It is not clear, in these contexts, that elevations of hs-CRP have any pathological significance. As a non-specific indicator of inflammation, CRP is also not a specific indicator of a single disease state such as cardiovascular disease but elevated concentrations can be seen in association with other comorbidities including obesity and pulmonary disease. In sharp contrast to the proposed inhibition of CRP for cardiovascular disease treatment, the infusion of CRP has been shown to have profound therapeutic benefits for autoimmune disease and septic shock. The balance between the risks and benefits of these competing views of the role of CRP in disease and disease therapy is reminiscent of the ongoing controversy regarding the use of non-steroidal anti-inflammatory drugs (NSAIDs) for musculoskeletal disease and their cardiovascular side effects. Soon, NSAIDs may not be the only agents about which Rheumatologists and Cardiologists may spar.

Increased hsCRP is associated with higher risk of aortic valve replacement in patients with aortic stenosis

Objective To investigate relations between inflammation and aortic valve stenosis (AS) by measuring high-sensitivity C-reactive protein, at baseline (hsCRP0) and after 1 year (hsCRP1) and exploring associations with aortic valve replacement (AVR). Design We examined 1423 patients from the Simvastatin and Ezetimibe in Aortic Stenosis study. Results During first year of treatment, hsCRP was reduced both in patients later receiving AVR (2.3 [0.9-4.9] to 1.8 [0.8-5.4] mg/l, p < 0.001) and not receiving AVR (1.90 [0.90-4.10] to 1.3 [0.6-2.9] mg/l, p < 0.001). In Cox-regression analyses, hsCRP1 predicted later AVR (HR = 1.17, p < 0.001) independently of hsCRP0 (HR = 0.96, p = 0.33), aortic valve area (AVA) and other risk factors. A higher rate of AVR was observed in the group with high hsCRP0 and an increase during the first year (AVRhighCRP0CRP1inc = 47.3% versus AVRhighCRP0CRP1dec = 27.5%, p < 0.01). The prognostic benefit of a 1-year reduction in hsCRP was larger in patients with high versus low hsCRP0 eliminating the difference in incidence of AVR between high versus low hsCRP0 (AVRhighCRP0CRP1dec = 27.5% versus AVRlowCRP0CRP1dec = 25.8%, p = 0.66) in patients with reduced hsCRP during the first year. Conclusions High hsCRP1 or an increase in hsCRP during the first year of follow-up predicted later AVR independently of AVA, age, gender and other risk factors, although no significant improvement in C-statistics was observed.

High-sensitivity C-reactive protein: a novel cardiovascular risk predictor in type 2 diabetics with normal lipid profile

BACKGROUND

India is the diabetic capital of the world. Coronary heart disease is a major cause of morbidity and mortality among diabetics. Type 2 diabetes mellitus and atherosclerosis are complex diseases sharing common antecedents like inflammation. High-sensitivity C-reactive protein (hs-CRP), an acute phase reactant protein, is a proinflammatory atherogenic circulating marker which can prove to be an independent cardiac risk predictor.

AIM

The aim of the present study was to evaluate the role of hs-CRP as an independent cardiovascular risk marker among Indians with type 2 diabetes with normal lipid profile.

SETTINGS AND DESIGN

This was a case control study including 60 type 2 diabetics with normal lipid profile and 60 age- and sex-matched healthy controls.

MATERIALS AND METHODS

Twelve-hour fasting blood samples were collected from all the participants. Serum was assayed for hs-CRP and lipid profile.

STATISTICAL ANALYSIS

Results were analyzed by unpaired t test.

RESULTS

We found elevated hs-CRP levels (4.8 ± 0.2, P < .0001) among cases compared to controls (0.9 ± 0.1). According to hs-CRP levels, seven cases were in the low-risk (< 1 mg/l), 32 in the moderate-risk (1-3 mg/l), and 21 in the high-risk (3-10 mg/l) group with mean values of hs-CRP of 0.7 ± 0.2, 1.75 ± 0.7, and 5.8 ± 1.4, respectively. Relative risk was 4.75 with odds ratio of 10.23 (95% confidence interval 8.8-11.23).

CONCLUSION

The study suggests that hs-CRP is an independent cardiac risk predictor even with normal lipid profile and can help measure additional risk. The American Heart Association stated that patients in the intermediate- and high-risk group may benefit from therapeutic lifestyle change and that cardiovascular event may be prevented.

T-cell immunosenescence and inflammatory response in atomic bomb survivors

In this paper we summarize the long-term effects of A-bomb radiation on the T-cell system and discuss the possible involvement of attenuated T-cell immunity in the disease development observed in A-bomb survivors. Our previous observations on such effects include impaired mitogen-dependent proliferation and IL-2 production, decreases in naive T-cell populations, and increased proportions of anergic and functionally weak memory CD4 T-cell subsets. In addition, we recently found a radiation dose-dependent increase in the percentages of CD25(+)/CD127(-) regulatory T cells in the CD4 T-cell population of the survivors. All these effects of radiation on T-cell immunity resemble effects of aging on the immune system, suggesting that ionizing radiation might direct the T-cell system toward a compromised phenotype and thereby might contribute to an enhanced immunosenescence. Furthermore, there are inverse, significant associations between plasma levels of inflammatory cytokines and the relative number of naïve CD4 T cells, also suggesting that the elevated levels of inflammatory markers found in A-bomb survivors can be ascribed in part to T-cell immunosenescence. We suggest that radiation-induced T-cell immunosenescence may result in activation of inflammatory responses and may be partly involved in the development of aging-associated and inflammation-related diseases frequently observed in A-bomb survivors.

Smoking and atherosclerotic cardiovascular disease: Part I: atherosclerotic disease process

The normal endothelium inhibits platelet and leukocyte adhesion to the vascular surface maintaining a balance of profibrinolytic and prothrombotic activity. Endothelial function is assessed largely as endothelium-dependent vasomotion, partly based on the assumption that impaired endothelium-dependent vasodilation reflects the alteration of important endothelial functions. Atherosclerotic risk factors, such as hypercholesterolemia, hypertension, diabetes and smoking, are associated with endothelial dysfunction. In the diseased endothelium, the balance between pro- and antithrombotic, pro- and anti-inflammatory, pro- and antiadhesive or pro- and antioxidant effects shifts towards a proinflammatory, prothrombotic, pro-oxidative and proadhesive phenotype of the endothelium. A common mechanism underlying endothelial dysfunction is related to the increased vascular production of reactive oxygen species. Recent studies suggest that inflammation per se, and C-reactive protein in particular, may contribute directly to endothelial dysfunction. The loss of endothelial integrity is a hallmark of atherosclerosis and the causal possible link between each individual risk factor, the development of atherosclerosis and the subsequent clinical events, such as myocardial infarction or stroke.

Translational mini-review series on immunology of vascular disease: inflammation, infections and Toll-like receptors in cardiovascular disease

Cardiovascular disease, in which atherosclerosis is the major underlying cause, is currently the largest cause of death in the world. Atherosclerosis is an inflammatory disease characterized by the formation of arterial lesions over a period of several decades at sites of endothelial cell dysfunction. These lesions are composed of endothelial cells, vascular smooth muscle cells, monocytes/macrophages and T lymphocytes (CD4(+)). As the lesions progress some can become unstable and prone to disruption, resulting in thrombus formation and possibly a myocardial infarction or stroke depending upon the location. Although the exact triggers for plaque disruption remain unknown, much recent evidence has shown a link between the incidence of myocardial infarction and stroke and a recent respiratory tract infection. Interestingly, many reports have also shown a link between a family of pattern recognition receptors, the Toll-like receptors, and the progression of atherosclerosis, suggesting that infections may play a role in both the progression of atherosclerosis and in inducing the more severe complications associated with the disease.

Interpretation of serum C-reactive protein (CRP) levels for cardiovascular disease risk is complicated by race, pulmonary disease, body mass index, gender, and osteoarthritis

OBJECTIVE

High-sensitivity C-reactive protein (hsCRP) in serum is used as a marker of risk for cardiovascular disease (CVD); however CRP is a non-specific acute phase reactant. We evaluated the association between hsCRP concentrations and the most common form of arthritis, osteoarthritis (OA), and assessed the applicability of hsCRP for CVD risk prediction.

METHODS

Participants (n=662) were selected from the population-based Johnston County Osteoarthritis Project, using stratified simple random sampling to achieve balance according to radiographic knee OA status, ethnic group, gender, and age group. The presence and severity of knee and hip OA were determined radiographically. CVD risk was estimated by hsCRP concentration and independently with the Framingham risk algorithm.

RESULTS

Serum natural log-transformed hsCRP (ln hsCRP) was higher in African-Americans (P<0.0001) and women (P<0.0001), was higher in participants who had chronic pulmonary disease (P=0.01), hypertension (P<0.0001), or used pain medications (P=0.004), and correlated with body mass index (BMI) (r=0.40, P<0.0001) and waist circumference (r=0.33, P<0.0001), but not with age, CVD, or current smoking. Ln hsCRP was strongly positively associated with all definitions of radiographic OA (rOA; P<0.0001), but this association was not independent of BMI. Although 183 participants reported no CVD and were classified as low risk by the Framingham CVD score, 61% of them were classified as moderate or high risk for CVD using hsCRP; this proportion designated high risk for CVD on the basis of hsCRP consisted primarily of women (P<0.05) and individuals with OA (P<0.01).

CONCLUSIONS

The pathogenic significance of hsCRP elevations in this subgroup is unclear. Serum hsCRP for predicting risk of CVD is confounded by obesity, ethnicity, gender and comorbidities.

Anti-inflammatory effects of atorvastatin: modulation by the T-786C polymorphism in the endothelial nitric oxide synthase gene

Statins produce cholesterol-independent, anti-inflammatory effects, which result at least in part from increased endothelial nitric oxide production. These effects may be modulated by polymorphisms in the endothelial nitric oxide synthase (eNOS) gene. Here, we examined whether the T-786C polymorphism of eNOS gene affects the concentrations of markers of atherosclerosis and inflammation (sCD40L, sVCAM-1, sICAM-1, sP-selectin, MCP-1, high sensitivity (hs)-CRP, MMP-2, MMP-9, and TIMP-1). We also studied whether atorvastatin-induced anti-inflammatory effects are modulated by this polymorphism. Healthy male volunteers (N=200), Caucasians, non-smokers, were genotyped for the T-786C polymorphism by restriction fragment length polymorphism. Subjects with TT or CC genotype received placebo for 14 days followed by 14 days of treatment with atorvastatin, 10mg/day p.o. The concentrations of inflammatory markers were measured with ELISA kits or by gelatin zymography. Serum cholesterol and LDL-cholesterol were significantly reduced after atorvastatin treatment in both genotype groups (P<0.05). No significant differences between genotype groups were found in the concentrations of the inflammatory markers after placebo. However, atorvastatin significantly reduced the concentrations of sCD40L, sVCAM-1, sP-selectin and MMP-9 in subjects with CC (but not TT) genotype (P<0.05). While atorvastatin decreased hs-CRP levels in both genotype groups (P<0.05), no significant effects were found on the concentrations of sICAM-1, MCP-1, pro-MMP-9, pro-MMP-2 and TIMP-1. These results suggest no effects for the T-786C polymorphism on the concentrations of inflammatory markers. However, this polymorphism modulates the anti-inflammatory effects of atorvastatin. These findings may be relevant for the primary prevention of cardiovascular events in subjects with CC genotype, who may be at increased cardiovascular risk and could benefit from treatment with statins.

The effects of effort-reward imbalance on inflammatory and cardiovascular responses to mental stress

OBJECTIVE

We examined the influence of effort-reward imbalance, a stressful feature of the work environment, on cardiovascular and inflammatory responses to acute mental stress.

METHODS

Ninety-two healthy men (mean age, 33.1 years) in full-time employment were recruited. Effort-reward imbalance was measured using a self-administered questionnaire. Blood, for the analysis of C-reactive protein (CRP) and von Willebrand factor (vWF) antigen, was sampled at baseline and 10 minutes after two mental stress tasks, whereas cardiovascular activity was measured throughout.

RESULTS

Plasma CRP and vWF were significantly elevated following the stress period, and cardiovascular activity was increased during and after both tasks (p < .001). Multiple linear regression analysis adjusted for age, body mass index, and baseline levels revealed that men with higher effort-reward imbalance demonstrated greater CRP and vWF responses to the stress tasks but blunted cardiovascular responses. Inflammatory and cardiovascular responses to stress appeared to be unrelated.

CONCLUSIONS

These findings suggest that the association between chronic work stress and cardiovascular disease risk may be mediated in part by heightened acute inflammatory responsivity. These responses appear not to result from differences in sympathoadrenal activation.