Coronary aspirate TNFα reflects saphenous vein bypass graft restenosis risk in diabetic patients

The immunopathology of coronary microembolization and the underlying inflammopathophysiological mechanisms

In coronary microembolization, inflammatory cell infiltration, patchy necrosis, and extensive intra-myocardial hemorrhage are dominant, which induce myocardial dysfunction with clinical symptoms of chronic ischemic cardiomyopathy. Microembolization can lead to obstruction of the coronary microvessels and result in the micro-infarction of the heart. The inflammation and elevated expression of the tumor necrosis factor in cardiomyocytes and the activation of extracellular ERK are involved in initiating the inflammatory response mechanism. The PI3K/Akt signaling pathway is the enriched pathway, and for controlling, inhibition of PI3K/Akt is necessary. Furthermore, the release of cytokines and the activation of inflammasomes contribute to the enhancement of vascular permeability, which results in edema within the myocardium. The immune response and inflammation represent the primary triggers in this process. The ability to control immune response and inflammation reactions may lead to the development of new therapies for microembolization.

Oxycodone protects cardiac microvascular endothelial cells against ischemia/reperfusion injury by binding to Sigma-1 Receptor

Endothelial dysfunction is an important mechanism involved in myocardial ischemia-reperfusion (I/R) injury. We aimed to explore the effects of Oxycodone on myocardial I/R injury in vivo and in vitro to reveal its mechanisms related to Sigma-1 Receptor (SIGMAR1). A rat model of I/R-induced myocardial injury was developed. The ischemic area and myocardial histopathological changes after oxycodone addition were evaluated by TTC staining and H&E staining. LDH, CK-MB and cTnI levels were used to assess myocardial function. Then, the endothelial integrity was reflected by the expressions of ZO-1, Claudin-1 and Occludin. Afterward, ELISA, RT-qPCR, western blot and immunofluorescence assays were adopted for the detection of inflammation-related genes. SIGMAR1 expression in myocardial tissues induced by I/R and cardiac microvascular endothelial cells (CMECs) under hypoxic/reoxygenation (H/R) was determined using RT-qPCR and western blotting. Subsequently, after SIGMAR1 silencing or BD1047 addition (a SIGMAR1 antagonist), cell apoptosis and endothelial integrity were analyzed in the presence of Oxycodone in H/R-stimulated CMECs. Results indicated that Oxycodone decreased the ischemic area and improved myocardial function in myocardial I/R injury rat. Oxycodone improved myocardial histopathological injury and elevated endothelial integrity, evidenced by upregulated ZO-1, Claudin-1 and Occludin expressions. Moreover, inflammatory response was alleviated after Oxycodone administration. Molecular docking suggested that SIGMAR1 could directly bind to Oxycodone. Oxycodone elevated SIGMAR1 expression and SIGMAR1 deletion or BD1047 addition attenuated the impacts of Oxycodone on apoptosis and endothelial integrity of CMECs induced by H/R. Collectively, Oxycodone alleviates myocardial I/R injury in vivo and in vitro by binding to SIGMAR1.

A fresh look at coronary microembolization

Mechanical stress from haemodynamic perturbations or interventional manipulation of epicardial coronary atherosclerotic plaques with inflammatory destabilization can release particulate debris, thrombotic material and soluble substances into the coronary circulation. The physical material obstructs the coronary microcirculation, whereas the soluble substances induce endothelial dysfunction and facilitate vasoconstriction. Coronary microvascular obstruction and dysfunction result in patchy microinfarcts accompanied by an inflammatory reaction, both of which contribute to progressive myocardial contractile dysfunction. In clinical studies, the benefit of protection devices to retrieve atherothrombotic debris during percutaneous coronary interventions has been modest, and the treatment of microembolization has mostly relied on antiplatelet and vasodilator agents. The past 25 years have witnessed a relative proportional increase in non-ST-segment elevation myocardial infarction in the presentation of acute coronary syndromes. An associated increase in the incidence of plaque erosion rather than rupture has also been recognized as a key mechanism in the past decade. We propose that coronary microembolization is a decisive link between plaque erosion at the culprit lesion and the manifestation of non-ST-segment elevation myocardial infarction. In this Review, we characterize the features and mechanisms of coronary microembolization and discuss the clinical trials of drugs and devices for prevention and treatment.

Cytokines as therapeutic targets for cardio- and cerebrovascular diseases

Despite major advances in prevention and treatment, cardiac and cerebral atherothrombotic complications still account for substantial morbidity and mortality worldwide. In this context, inflammation is involved in the chronic process leading atherosclerotic plaque formation and its complications, as well as in the maladaptive response to acute ischemic events. For this reason, modulation of inflammation is nowadays seen as a promising therapeutic strategy to counteract the burden of cardio- and cerebrovascular disease. Being produced and recognized by both inflammatory and vascular cells, the complex network of cytokines holds key functions in the crosstalk of these two systems and orchestrates the progression of atherothrombosis. By binding to membrane receptors, these soluble mediators trigger specific intracellular signaling pathways eventually leading to the activation of transcription factors and a deep modulation of cell function. Both stimulatory and inhibitory cytokines have been described and progressively reported as markers of disease or interesting therapeutic targets in the cardiovascular field. Nevertheless, cytokine inhibition is burdened by harmful side effects that will most likely prevent its chronic use in favor of acute administrations in well-selected subjects at high risk. Here, we summarize the current state of knowledge regarding the modulatory role of cytokines on atherosclerosis, myocardial infarction, and stroke. Then, we discuss evidence from clinical trials specifically targeting cytokines and the potential implication of these advances into daily clinical practice.

Percutaneous coronary intervention in diabetic versus non-diabetic patients with prior coronary artery bypass grafting: a propensity score matching study

BACKGROUND

The target of this study was to explore the outcomes of percutaneous coronary intervention (PCI) in diabetic versus non-diabetic patients with prior coronary artery bypass grafting (CABG) surgery.

METHODS

Seven hundred and twenty four patients who had previously received CABG and had been treated using PCI combined with drug-eluting stents (DES) between 2009 and 2017 were selected for a retrospective study and allocated into either a diabetes mellitus (DM) or non-diabetes mellitus (No DM) group. A 1:1 propensity score-matched evaluation was conducted and risk adjusted for analysis. The primary outcomes were cardiac death, myocardial infarction, heart failure and revascularization, with a median follow-up duration of 5.13 years.

RESULTS

After matching, two-, 5- and 8-year event rate of overall major adverse cardiac events (MACEs) were found to be higher in the DM group (No DM vs DM:15.3, 30.9, 38.5% vs 19.8, 37.8, 52.2%, respectively), although no significant difference was found in the event rate of overall MACEs (hazard ratio [HR]: 1.35; 95% confidence interval [CI]: 1.00 to 1.83 for DM vs No DM; P = 0.052), cardiac death (HR: 0.94; 95% CI: 0.45 to 1.95; P = 0.871), MI (HR: 1.49; 95% CI: 0.95 to 2.32; P = 0.080), HF (HR: 1.54; 95% CI: 0.90 to 2.63 for; P = 0.120) or revascularization (HR: 1.07; 95% CI: 0.72 to 1.59; P = 0.747). Subgroup analysis of PCI in only the NCA showed MACEs (adjusted HR: 1.13; 95% CI: 0.85 to 1.49 for DM vs No DM; P = 0.325), cardiac death (adjusted HR: 0.85; 95% CI: 0.41 to 1.78 for DM vs No DM; P = 0.781), MI (adjusted HR: 1.32; 95% CI: 0.84 to 2.01 for DM vs No DM; P = 0.069), HF (adjusted HR: 1.41; 95% CI: 0.87 to 2.27 for DM vs No DM; P = 0.211) or repeated revascularization (adjusted HR: 0.93; 95% CI: 0.64 to 1.37 for DM vs No DM; P = 0.836).

CONCLUSIONS

Compared with non-diabetic patients with prior CABG, subsequent implantation of DES in the native coronary artery of diabetic patients resulted in apparently similar outcomes.

TRIAL REGISTRATION

This study was not registered in an open access database.

Promoting effect of baicalin on nitric oxide production in CMECs via activating the PI3K-AKT-eNOS pathway attenuates myocardial ischemia-reperfusion injury

OBJECTIVE

Baicalin, which is isolated from Scutellariae Radix, has been shown to possess therapeutic potential for different diseases. Cardiac microvessel injury in myocardial ischemia-reperfusion (IR) has been extensively explored. However, there have been no studies investigating the physiological regulatory mechanisms of baicalin on nitric oxide production and the necroptosis of cardiac microvascular endothelial cells (CMECs) in myocardial IR injury. This study was designed to investigate the contribution of baicalin to repressing necroptosis and preventing IR-mediated CMEC dysfunction.

MATERIALS AND METHODS

Indicators of ventricular structure and function were measured by an echocardiographic system. An MTT assay was performed to assess cell viability. Nitrite detection was performed to detect nitric oxide content, and cGMP content was determined using a commercially available cGMP complete ELISA kit. Morphology and molecular characteristics were detected by electron micrographs, quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting.

RESULT

Our results demonstrated that baicalin significantly improved cardiac function, decreased the myocardial infarction area, and inhibited myocardial cell apoptosis. Moreover, baicalin had a protective effect on cardiac microvessels and promoted the production of nitric oxide (NO) and the level of cGMP in rats that underwent myocardial IR injury. The results of the in vitro experiments showed that baicalin markedly improved cell activity and function in CMECs exposed to hypoxia-reoxygenation (HR). Further experiments indicated that baicalin supplementation suppressed the protein expression of RIP1, RIP3 and p-MLKL to interrupt CMEC necroptosis. In addition, baicalin promoted the production of NO via activating the PI3K-AKT-eNOS signaling pathway. Taken together, our results identified the PI3K-AKT-eNOS axis as a new pathway responsible for reperfusion-mediated microvascular damage.

CONCLUSION

Baicalin protected CMECs in IR rats by promoting the release of NO via the PI3K-AKT-eNOS pathway and mitigated necroptosis by inhibiting the protein expression of RIP1, RIP3 and p-MLKL.

Coronary microembolization and microvascular dysfunction

Plaque erosion, fissuring or rupture occurs spontaneously or during coronary interventions. At some residual blood flow, the atherothrombotic debris is washed into the coronary microcirculation, causing physical obstruction, vasoconstriction, inflammation and ultimately microinfarction. Coronary microembolization also contributes to microvascular obstruction in reperfused acute myocardial infarction. Patients with microvascular obstruction after reperfused myocardial infarction have worse prognosis. Cardioprotective strategies to avoid acute coronary microembolization and rescue myocardium from microvascular obstruction have not yet been established in clinical practice. Subclinical coronary microembolization together with release of thrombogenic, vasoconstrictor and inflammatory substances from a culprit lesion can sensitize the coronary microcirculation and contribute to angina in the absence of major epicardial coronary obstruction. Repetitive coronary microembolization can induce progressive loss of functional cardiomyocytes and induce heart failure in the absence of overt myocardial infarction.

The impact of diabetes mellitus on long-term clinical outcomes after percutaneous coronary saphenous vein graft interventions in the drug-eluting stent era

OBJECTIVES

We aimed to compare early and late clinical outcomes in diabetic and nondiabetic patients who underwent saphenous vein graft (SVG) percutaneous coronary interventions (PCI) with the use of drug-eluting stents (DES).

BACKGROUND

Patients with diabetes mellitus are shown to have less favorable outcomes after SVG intervention with the use of bare metal stents. In the DES era, the impact of diabetes mellitus on restenosis and clinical outcomes post-SVG intervention is not clearly defined.

METHODS

From our institutional PCI registry database, we retrospectively analyzed 477 consecutive patients with prior coronary artery bypass graft surgery undergoing SVG PCI with the implantation of DES stratified by the presence or absence of diabetes mellitus. The primary end-point was 1-year major adverse cardiac event (MACE) rate, defined as death, Q wave myocardial infarction, and target lesion revascularization.

RESULTS

Baseline clinical characteristics, including mean graft age (120 ± 77 vs. 131 ± 86 months, P = 0.14), were similar between groups, save for a higher prevalence of systemic hypertension and chronic renal insufficiency, and higher body mass index in the diabetic group. Among the 604 SVG lesions treated with DES, the angiographic and procedural characteristics were well matched between groups except for the higher rate of distal protection device use (32% vs. 29%, P = 0.007) in the diabetic group. The rates of 1-year MACE (21% vs. 15%, P = 0.12) and all-cause mortality (7.6% vs. 6.7%, P = 0.86) were similar between groups. After adjustment for the relevant clinical co-variables, diabetic status was not associated with the composite end-point.

CONCLUSION

In conclusion, DES, when used for the treatment of vein graft lesions, equate the short- and long-term outcomes between diabetic and nondiabetic patients, suggesting that DES should be considered the default stent in diabetic populations undergoing PCI for the treatment of SVG lesions.

Putative consequences of exposure to Helicobacter pylori infection in patients with coronary heart disease in terms of humoral immune response and inflammation

INTRODUCTION

Pathogens, including Helicobacter pylori (Hp), have been suggested to contribute to the development of coronary heart disease (CHD), although the evidence still remains insufficient. The study was focused on the exposure of CHD patients to Hp and resulting anti-Hp heat shock protein B HspB antibody production in relation to the level of serum lipopolysaccharide binding protein (LBP) as a marker of inflammation.

MATERIAL AND METHODS

One hundred seventy CHD patients and 58 non-CHD individuals participated in this study. Coronary angiography confirmed the atheromatic background of CHD. The panel of classical risk factors included: arterial hypertension, diabetes, total cholesterol, low-density lipoprotein (LDL)/high-density lipoprotein (HDL) cholesterol, triglycerides, obesity and nicotinism. The Hp status was estimated by (13)C urea breath test and serology. Immunoblot and ELISA were used for screening the sera samples for anti-Hp HspB immunoglobulins (Igs) and LBP.

RESULTS

Coronary heart disease patients were exposed to Hp more frequently than non-CHD individuals. This was associated with increased levels of specific anti-Hp IgG2 and IgA as well as total IgA. Hp infected CHD and non-CHD donors produced anti-Hp HspB IgG cross-reacting with human Hsp 60. In CHD patients the LBP level was significantly higher in comparison to non-CHD donors. This was related to the severity of the disease. Type I Hp strains stimulated higher LBP levels than less pathogenic type II isolates.

CONCLUSIONS

Lipopolysaccharide binding protein secreted in excess together with anti-Hp HspB, cross-reacting with human Hsp60, may increase the risk of vascular pathologies in Hp-exposed CHD patients.

Interaction of risk factors, comorbidities, and comedications with ischemia/reperfusion injury and cardioprotection by preconditioning, postconditioning, and remote conditioning

Pre-, post-, and remote conditioning of the myocardium are well described adaptive responses that markedly enhance the ability of the heart to withstand a prolonged ischemia/reperfusion insult and provide therapeutic paradigms for cardioprotection. Nevertheless, more than 25 years after the discovery of ischemic preconditioning, we still do not have established cardioprotective drugs on the market. Most experimental studies on cardioprotection are still undertaken in animal models, in which ischemia/reperfusion is imposed in the absence of cardiovascular risk factors. However, ischemic heart disease in humans is a complex disorder caused by, or associated with, cardiovascular risk factors and comorbidities, including hypertension, hyperlipidemia, diabetes, insulin resistance, heart failure, altered coronary circulation, and aging. These risk factors induce fundamental alterations in cellular signaling cascades that affect the development of ischemia/reperfusion injury per se and responses to cardioprotective interventions. Moreover, some of the medications used to treat these risk factors, including statins, nitrates, and antidiabetic drugs, may impact cardioprotection by modifying cellular signaling. The aim of this article is to review the recent evidence that cardiovascular risk factors and their medication may modify the response to cardioprotective interventions. We emphasize the critical need to take into account the presence of cardiovascular risk factors and concomitant medications when designing preclinical studies for the identification and validation of cardioprotective drug targets and clinical studies. This will hopefully maximize the success rate of developing rational approaches to effective cardioprotective therapies for the majority of patients with multiple risk factors.

Release of Intracoronary Microparticles during Stent Implantation into Stable Atherosclerotic Lesions under Protection with an Aspiration Device

OBJECTIVE

Stent implantation into atherosclerotic coronary vessels impacts on downstream microvascular function and induces the release of particulate debris and soluble substances, which differs qualitatively and quantitatively between native right coronary arteries (RCAs) and saphenous vein grafts on right coronary arteries (SVG-RCAs). We have now quantified the release of microparticles (MPs) during stent implantation into stable atherosclerotic lesions and compared the release between RCAs and SVG-RCAs.

METHODS

In symptomatic, male patients with stable angina and a stenosis in their RCA or SVG-RCA, respectively (n = 14/14), plaque volume and composition were analyzed using intravascular ultrasound before stent implantation. Coronary aspirate was retrieved during stent implantation with a distal occlusion/aspiration device and divided into particulate debris and plasma. Particulate debris was weighed. Platelet-derived MPs (PMPs) were distinguished by flow cytometry as CD41+, endothelium-derived MPs (EMPs) as CD144+, CD62E+ and CD31+/CD41-, leukocyte-derived MPs as CD45+, and erythrocyte-derived MPs as CD235+.

RESULTS

In patients with comparable plaque volume and composition in RCAs and SVG-RCAs, intracoronary PMPs and EMPs were increased after stent implantation into their RCAs and SVG-RCAs (CD41+: 2729.6 ± 645.6 vs. 4208.7 ± 679.4 and 2355.9 ± 503.9 vs. 3285.8 ± 733.2 nr/µL; CD144+: 451.5 ± 87.9 vs. 861.7 ± 147.0 and 444.6 ± 74.8 vs. 726.5 ± 136.4 nr/µL; CD62E+: 1404.1 ± 247.7 vs. 1844.3 ± 378.6 and 1084.6 ± 211.0 vs. 1783.8 ± 384.3 nr/µL, P < 0.05), but not different between RCAs and SVG-RCAs.

CONCLUSION

Stenting in stable atherosclerotic lesions is associated with a substantial release not only of PMPs, but also of EMPs in RCAs and SVG-RCAs. Their release does not differ between RCAs and SVG-RCAs.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01430884.

TXNIP mediates NLRP3 inflammasome activation in cardiac microvascular endothelial cells as a novel mechanism in myocardial ischemia/reperfusion injury

NLRP3 inflammasome is necessary for initiating acute sterile inflammation. Recent studies have demonstrated that NLRP3 inflammasome is up-regulated and mediates myocardial ischemia/reperfusion (MI/R) injury. However, the signaling pathways that lead to the activation of NLRP3 inflammasome by MI/R injury have not been fully elucidated. C57BL/6J mice were subjected to 30 min ischemia and 3 or 24 h reperfusion. The ischemic heart exhibited enhanced inflammasome activation as evidenced by increased NLRP3 expression and caspase-1 activity and increased IL-1β and IL-18 production. Intramyocardial NLRP3 siRNA injection or an intraperitoneal injection of BAY 11-7028, an inflammasome inhibitor, attenuated macrophage and neutrophil infiltration and decreased MI/R injury, as measured by cardiomyocyte apoptosis and infarct size. The ischemic heart also exhibited enhanced interaction between Txnip and NLRP3, which has been shown to be a mechanism for activating NLRP3. Intramyocardial Txnip siRNA injection also decreased infarct size and NLRP3 activation. In vitro experiments revealed that NLRP3 was expressed in cardiac microvascular endothelial cells (CMECs), but was hardly expressed in cardiomyocytes. Simulated ischemia/reperfusion (SI/R) stimulated NLRP3 inflammasome activation in CMECs, but not in cardiomyocytes. Moreover, CMECs subjected to SI/R injury increased interactions between Txnip and NLRP3. Txnip siRNA diminished NLRP3 inflammasome activation and SI/R-induced injury, as measured by LDH release and caspase-3 activity in CMECs. ROS scavenger dissociated TXNIP from NLRP3 and inhibited the activation of NLRP3 inflammasome in the CMECs. For the first time, we demonstrated that TXNIP-mediated NLRP3 inflammasome activation in CMECs was a novel mechanism of MI/R injury. Interventions that block Txnip/NLRP3 signaling to inhibit the activation of NLRP3 inflammasomes may be novel therapies for mitigating MI/R injury.

Adiponectin: a manifold therapeutic target for metabolic syndrome, diabetes, and coronary disease?

Adiponectin is the most abundant peptide secreted by adipocytes, being a key component in the interrelationship between adiposity, insulin resistance and inflammation. Central obesity accompanied by insulin resistance is a key factor in the development of metabolic syndrome (MS) and future macrovascular complications. Moreover, the remarkable correlation between coronary artery disease (CAD) and alterations in glucose metabolism has raised the likelihood that atherosclerosis and type 2 diabetes mellitus (T2DM) may share a common biological background. We summarize here the current knowledge about the influence of adiponectin on insulin sensitivity and endothelial function, discussing its forthcoming prospects and potential role as a therapeutic target for MS, T2DM, and cardiovascular disease. Adiponectin is present in the circulation as a dimer, trimer or protein complex of high molecular weight hexamers, >400 kDa. AdipoR1 and AdipoR2 are its major receptors in vivo mediating the metabolic actions. Adiponectin stimulates phosphorylation and AMP (adenosin mono phosphate) kinase activation, exerting direct effects on vascular endothelium, diminishing the inflammatory response to mechanical injury and enhancing endothelium protection in cases of apolipoprotein E deficiency. Hypoadiponectinemia is consistently associated with obesity, MS, atherosclerosis, CAD, T2DM. Lifestyle correction helps to favorably modify plasma adiponectin levels. Low adiponectinemia in obese patients is raised via continued weight loss programs in both diabetic and nondiabetic individuals and is also accompanied by reductions in pro-inflammatory factors. Diet modifications, like intake of fish, omega-3 supplementation, adherence to a Mediterranean dietary pattern and coffee consumption also increase adiponectin levels. Antidiabetic and cardiovascular pharmacological agents, like glitazones, glimepiride, angiotensin converting enzyme inhibitors and angiotensin receptor blockers are also able to improve adiponectin concentration. Fibric acid derivatives, like bezafibrate and fenofibrate, have been reported to enhance adiponectin levels as well. T-cadherin, a membrane-associated adiponectin-binding protein lacking intracellular domain seems to be a main mediator of the antiatherogenic adiponectin actions. The finding of novel pharmacologic agents proficient to improve adiponectin plasma levels should be target of exhaustive research. Interesting future approaches could be the development of adiponectin-targeted drugs chemically designed to induce the activaton of its receptors and/or postreceptor signaling pathways, or the development of specific adiponectin agonists.

Syndecan-1 regulates vascular smooth muscle cell phenotype

OBJECTIVE

We examined the role of syndecan-1 in modulating the phenotype of vascular smooth muscle cells in the context of endogenous inflammatory factors and altered microenvironments that occur in disease or injury-induced vascular remodeling.

METHODS AND RESULTS

Vascular smooth muscle cells (vSMCs) display a continuum of phenotypes that can be altered during vascular remodeling. While the syndecans have emerged as powerful and complex regulators of cell function, their role in controlling vSMC phenotype is unknown. Here, we isolated vSMCs from wild type (WT) and syndecan-1 knockout (S1KO) mice. Gene expression and western blotting studies indicated decreased levels of α-smooth muscle actin (α-SMA), calponin, and other vSMC-specific differentiation markers in S1KO relative to WT cells. The spread area of the S1KO cells was found to be greater than WT cells, with a corresponding increase in focal adhesion formation, Src phosphorylation, and alterations in actin cytoskeletal arrangement. In addition, S1KO led to increased S6RP phosphorylation and decreased AKT and PKC-α phosphorylation. To examine whether these changes were present in vivo, isolated aortae from aged WT and S1KO mice were stained for calponin. Consistent with our in-vitro findings, the WT mice aortae stained higher for calponin relative to S1KO. When exposed to the inflammatory cytokine TNF-α, WT vSMCs had an 80% reduction in syndecan-1 expression. Further, with TNF-α, S1KO vSMCs produced increased pro-inflammatory cytokines relative to WT. Finally, inhibition of interactions between syndecan-1 and integrins αvβ3 and αvβ5 using the inhibitory peptide synstatin appeared to have similar effects on vSMCs as knocking out syndecan-1, with decreased expression of vSMC differentiation markers and increased expression of inflammatory cytokines, receptors, and osteopontin.

CONCLUSIONS

Taken together, our results support that syndecan-1 promotes vSMC differentiation and quiescence. Thus, the presence of syndecan-1 would have a protective effect against vSMC dedifferentiation and this activity is linked to interactions with integrins αvβ3 and αvβ5.

Inflammatory biomarkers in type 2 diabetic patients: effect of glycemic control and impact of LDL subfraction phenotype

Background

Type 2 diabetes mellitus (T2D) is associated with higher cardiovascular risk partly related to an increase in inflammatory parameters. The aim of this study was to determine the association of inflammatory biomarkers with low-density lipoprotein (LDL) subfraction phenotype and glycemic control in subjects with T2D and poor glycemic control.

Methods

A cross-sectional study was performed comparing 122 subjects with T2D (59 ± 11 years old, body mass index 30.2 ± 5.6 kg/m2) with 54 control subjects. Patients with T2D were classified according to their LDL subfraction phenotype and inflammatory biomarkers (C-reactive protein, Interleukin-6, Interleukin-8, Transforming growth factor β₁, Monocyte chemotactic protein 1, Leptin, Adiponectin) were evaluated according to the degree of glycemic control, LDL phenotype and other clinical characteristics. Forty-two subjects with T2D were studied before and after 3 months of improving glycemic control by different strategies.

Results

Patients with T2D had higher C-reactive protein (CRP) and monocyte chemotactic protein-1 (MCP1) levels and lower adiponectin concentration, compared to controls. T2D subjects with body mass index ≥ 30 kg/m2 had higher CRP levels (5.2 ± 4.8 mg/l vs 3.7 ± 4.3 mg/l; p < 0.05). The presence of LDL phenotype B was related to higher levels of transforming growth factor-β₁ (TGF-β₁) (53.92 ± 52.82 ng/l vs 31.35 ± 33.74 ng/l; p < 0.05) and lower levels of adiponectin (3663 ± 3044 ng/l vs 2723 ± 1776 ng/l; p < 0.05). The reduction of HbA1c from 9.5 ± 1.8% at baseline to 7.4 ± 0.8% was associated with a significant reduction of TGF-β₁ (41.86 ± 32.84 ng/l vs 26.64 ± 26.91 ng/l; p = 0.02).

Conclusions

Subjects with T2D, especially those with LDL phenotype B and obesity, have higher levels of inflammatory biomarkers. Improvement of glycemic control reduces TGF-β₁ levels, which may contribute partly to its renoprotective role.