Plaque Inflammation Research Articles

Inflammatory activity of vulnerable plaques in asymptomatic, non-hemodynamically significant carotid artery stenoses: preliminary results of the carotid artery multi-modality imaging prognostic study

Abstract Background [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) is a valid technique to quantify carotid plaque inflammation and can improve identification of patients at high risk for stroke. There are few data on the inflammatory plaque activity in asymptomatic patients and of its association with other characteristics of plaque vulnerability. Purpose To assess the inflammatory carotid plaque activity and its correlations with patient characteristics and features of plaque vulnerability detected by other imaging techniques in a population of patients with asymptomatic mild/moderate degree of stenosis. Methods Seventy-five asymptomatic patients with 40-60% unilateral carotid stenosis at Doppler ultrasound (DUS) were prospectively evaluated with [18F]FDG-PET, computed tomography angiography (CTA), and magnetic resonance angiography (MRA). Regions of interests were drawn using fused PET/CT slices on the most diseased segment (MDS), defined as the single hottest slice of [18F]FDG uptake. Background blood pool activity was obtained from regions of interests placed in the lumen of the jugular vein. The target-to-background ratio (TBR) was calculated by dividing maximum standardized uptake value (SUVmax) of the MDS to SUVmax of ipsilateral blood pool activity. Plaque vulnerability was defined as the presence of an echolucent plaque at DUS, plaque ulceration at CTA, intraplaque hemorrhage, and lipid-rich necrotic core at MRA. Results Patients with a TBR ≥median (1.75), compared with those below the median, were significantly more frequently male and on statin therapy, had higher prevalence of ulcerated plaque at CTA (61% vs 35%, p=0.03) and intraplaque hemorrhage at MRA (33% vs 10%, p=0.03), while the prevalence of a lipid-rich necrotic core at MRA was not significantly different (p=0.16). TBR and SUVmax of the MDS were similar in those with or without a ≥50% stenosis, and peak velocities indices at DUS were not significantly correlated with TBR or SUVmax. Log(TBR) was significantly higher in ulcerated, rather than non-ulcerated, plaque (0.27 vs 0.21, p=0.03) and numerically higher in plaques with an intraplaque hemorrhage (0.22 vs 0.30, p=0.06). Log(TBR) and Log(SUVmax) were similar in plaques with and without a lipid-rich necrotic core (p=0.86 for both). Conclusions Higher TBR or SUVmax, indicating a high inflammatory activity, are associated with an ulcerated plaque and the presence of intraplaque hemorrhage but not with either the degree of stenosis or the presence of a lipid-rich necrotic core.

The effect of proprotein convertase subtilisin/kexin type 9 inhibition on the plasma proteome: a SPIRE sub-study

Abstract Background The plasma proteome is an intermediate phenotype for disease and is a tool to inform on pharmacological mechanisms of effect. For selective low-density lipoprotein cholesterol (LDL-C) lowering by proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition, multiple studies have demonstrated that its potent LDL-C lowering effect coincides with marked reductions in both cellular and arterial plaque inflammation, despite unaltered high-sensitivity C-reactive protein (hs-CRP) levels. Purpose In the present study, we set out to investigate potential anti-inflammatory effects of PCSK9 inhibition using plasma proteomics. Methods In 190 patients participating in the SPIRE-1/2 trials, 184 targeted proteins were measured at baseline and after 12 months of bococizumab treatment using the Cardiovascular II and III panels (Sweden). Of the included patients, 96 patients received placebo and 94 received 150mg of bococizumab, once every two weeks. Considering the development of auto-antibodies in some patients, patients with LDL-C reduction below 15% were excluded. The primary outcome was the fold change in protein levels after 12 months compared to baseline. The Benjamini-Hochberg method was used to adjust for multiple comparisons with a false discovery rate (FDR) of 5%. The findings were compared to the LoDoCo2 sub-study which used the same proteomic panels. Results In the placebo group, there was no significant change in any of the proteins. In the bococizumab group (n=77, mean age 62.2±9.7 years and 70 [91%] male), LDL-C levels were reduced from 114±41 mg/dL to 47±34 mg/dL (mean reduction 66±29 mg/dL) on top of statin therapy while there was a neutral effect on hs-CRP (median change 0.0 mg/L IQR [-0.8,1.1]). PCSK9 was the only protein with change upon treatment with bococizumab (24.4±11.0 vs. 15.0±10.7; PFDR=0.033; Figure 1A). In comparison, treatment of colchicine in the LoDoCo2 sub-study was associated with a significant change in 60 proteins (Figure 1B). Conclusion Here, we show that PCSK9 inhibition with bococizumab resulted in a highly selective reduction of PCSK9 plasma levels without robustly affecting other circulating proteins in the measured panels, implying PCSK9 inhibition lowers ASCVD risk via pure lipid lowering pathways. Our study reinforces the neutral systemic inflammatory effect of PCSK9 inhibition on top of statin therapy. The local effects on cellular and vascular inflammation by PCSK9 inhibition observed in earlier studies most likely reflect a direct consequence of a reduced cholesterol content in inflammatory cells and plaques, subsequently leading to a local anti-inflammatory effect. These findings support the combination of targeted anti-inflammatory therapies on top of potent LDL-C lowering in order to further reduce the residual inflammatory risk.

Computed tomography plaque analysis identifies residual inflammation in recent acute myocardial infarction patients

Abstract Introduction Residual inflammatory risk (RIR) following acute myocardial infarction (AMI) patients is associated with recurrent major adverse cardiovascular events. Atherosclerotic plaque quantification using computed tomographic coronary angiography (CTCA) can specifically identify inflamed plaque characteristics. We compared plaque burden and tissue composition in AMI patients with those of stable coronary artery disease (CAD) patients to identify imaging markers of RIR. Purpose We aimed to identify signs of residual inflammation in recent AMI patients via CTCA atheroma quantification. We hypothesised that recent AMI patients have plaque characteristics suggestive of inflammation. Methods 108 patients recruited from multiple sites with AMI <1 month were propensity-matched via CAD risk factors (age, gender, diabetes, hypertension, hyperlipidaemia, smoking and family history of CAD) with stable CAD patients in a 1:1 ratio. Propensity matched recent AMI and stable CAD patient cohorts had similar profiles: age (60±9.7 vs 57±10.0 years), gender (91.7% vs 92.6% male), diabetes (13.9% vs 15.7%), hypertension (44.4% vs 50.9%) and hyperlipidaemia (50.9% vs 63.9%, p>0.05 for all). Total plaque burden (total lesion volume/total vessel volume) and plaque composition (fibrous fatty [fibrofatty, FF, 31 – 130 HU], necrotic core [NC, -30 – 30 HU], fibrous [131 – 350 HU] and calcium [> 350 HU]) were extracted from CTCA scans and aggregated per patient. Culprit lesions of recent AMI patients were excluded from the analysis due to the fact that coronary stents would affect plaque characterisation. Multivariate linear regression, corrected for CAD risk factors, was used to compare these parameters between the two cohorts. Results Recent AMI patients and stable CAD patients had similar total plaque burden (β=0.001±0.013, p=0.950, Figure 1a). Patients with recent AMI had higher non-calcified plaque volume ratio (β=0.071±0.026, p<0.05, Figure 1b) due to higher FF (β=0.094±0.019, Figure 1d) and NC (β=0.025 ± 0.005, Figure 1e) plaque volume (p<0.05 for all), but less fibrous plaque volume (β = -0.048±0.019, p<0.05, Figure 1c). Conclusions Recent AMI patients had a greater non-calcified plaque burden than stable CAD patients due to larger FF and NC plaque burden. Since FF and NC components indicate ongoing inflammation in the plaque, while fibrous content indicates resolved inflammation; increased NC and FF burden suggest increased coronary plaque inflammation in non-culprit lesions of recent AMI patients, supporting the presence of residual inflammation in recent AMI patients.Figure 1

Reduction of perivascular inflammation following long-term statin treatment - a coronary CT follow-up study using Fat Attenuation Index

Abstract Background Perivascular fat attenuation index (FAI) assessed by coronary computed tomography (CCTA) has been demonstrated to represent a reliable marker of coronary inflammation. Several studies have explored the potential anti-inflammatory effects of statins in reducing the risk of plaque rupture and subsequent cardiovascular events. However, the effect of statin therapy on FAI has not been clearly demonstrated so far. Purpose Our objective was to investigate the changes in perivascular FAI at the level of coronary lesions, as measured by coronary computed tomography (CCTA), following long-term high-dose statin therapy. Methods This study includes 23 patients who presented with typical chest pain, had a low to intermediate likelihood of coronary artery disease, and underwent a CCTA examination which revealed the existence of at least one coronary atheromatous plaque. Statin therapy was initiated in all patients according to guidelines. The CCTA was repeated after a time interval ranging from 1.5 to 3 years. Lesion-specific perivascular FAI, together with different plaque characteristics, were measured at both baseline and follow-up using a new AI-powered medical device called CaRi-Heart®. Results The mean age of the participants was 61.72 ± 8.86 at the time of the first scan, and 65.21% (n = 15) of them were male. At baseline, the CT density of the adipose tissue (ranging from -190 to -30 HU), was not significantly different between the two groups. A significant decrease in serum lipids following statin therapy was recorded during follow-up: from 193.4 ± 47.09 to 145.2 ± 34.7, p = 0.04 for total cholesterol, and from 101.77 ± 25.20 to 86.41 ± 21.09, p = 0.02 for LDL cholesterol. The FAI-score consistently decreased from baseline to follow-up, especially in the left anterior descending artery: from 15.87 ± 9.32 vs. 12.40 ± 7.55, p = 0.04, while there was no significant decrease in coronary inflammation at the level of left circumflex artery (13.98 ± 6.16 vs. 13.10 ± 6.59, p = ns), or right coronary artery (20.53 ± 13.74 vs. 19.96 ± 16.24, p = ns). Similarly, the FAI-Score Centile values were lower during the second scan, specifically for LAD (0.51 ± 0.28 vs. 0.69 ± 0.29, p = 0.04), while there were no significant differences of FAI score centile in the LCX (0.72 ± 0.28 vs. 0.74 ± 0.26, p = ns) and RCA (0.71 ± 0.32 vs. 0.78 ± 0.21, p = ns). Conclusion CaRi-Heart® mapping technology revealed a significant decrease of coronary inflammation, as expressed by the FAI-score, as a result of high-dose statin treatment especially at the level of the LAD. This indicates a potential role of local factors related to coronary circulation in the complex process of plaque inflammation. The perivascular FAI-score and FAI-score centile may serve as promising imaging biomarkers for monitoring the anti-inflammatory response to statin treatments.Color-coded FAI MappingPVAT-FAI Score of Coronary Inflammation

Ficolin-2 amplifies inflammation in macrophage-smooth muscle cell cross-talk and increases monocyte transmigration by mechanisms involving IL-1β and IL-6

Ficolin-2, recently identified in atherosclerotic plaques, has been correlated with future acute cardiovascular events, but its role remains unknown. We hypothesize that it could influence plaque vulnerability by interfering in the cross-talk between macrophages (MØ) and smooth muscle cells (SMC). To examine its role and mechanism of action, we exposed an in-vitro co-culture system of SMC and MØ to ficolin-2 (10 µg/mL) and then performed cytokine array, protease array, ELISA, qPCR, Western Blot, and monocyte transmigration assay. Carotid plaque samples from atherosclerotic patients with high plasma levels of ficolin-2 were analyzed by immunofluorescence. We show that ficolin-2: (i) promotes a pro-inflammatory phenotype in SMC following interaction with MØ by elevating the gene expression of MCP-1, upregulating gene and protein expression of IL-6 and TLR4, and by activating ERK/MAPK and NF-KB signaling pathways; (ii) increased IL-1β, IL-6, and MIP-1β in MØ beyond the level induced by cellular interaction with SMC; (iii) elevated the secretion of IL-1β, IL-6, and CCL4 in the conditioned medium; (iv) enhanced monocyte transmigration and (v) in atherosclerotic plaques from patients with high plasma levels of ficolin-2, we observed co-localization of ficolin-2 with SMC marker αSMA and the cytokines IL-1β and IL-6. These findings shed light on previously unknown mechanisms underlying ficolin-2–dependent pathological inflammation in atherosclerotic plaques.

Abstract 15654: Layered Plaques and Plaque Vulnerability in Patients With Stable Angina Pectoris

Backgrounds: Layered plaque, a signature of previous plaque destabilization and healing, is one of the predictors for rapid plaque progression, the mechanism of which is unknown. Aims: To investigate the level of vascular inflammation and plaque vulnerability in layered plaques to elucidate possible mechanisms of rapid plaque progression. Methods: Patients who underwent both coronary computed tomography angiography (CTA) and optical coherence tomography (OCT) were selected. Plaques were defined as any tissue (noncalcified, calcified, or mixed) within or adjacent to the lumen. Pericoronary adipose tissue (PCAT) attenuation was measured at the plaque level on CTA. OCT features of plaque vulnerability were assessed at the corresponding site. Results: A total of 475 plaques from 195 patients presented with stable angina pectoris were included. Layered plaques (n=241), compared to non-layered plaques (n=234), had a higher level of vascular inflammation (-70.94 [-77.86, -64.66] HU vs. -73.52 [-80.83, -67.66] HU, P=0.014, Figure 1). Layered plaques also had a higher prevalence of the features of plaque vulnerability (Figure 2), including lipid-rich plaque (83.8% vs. 66.7%, P<0.001), thin-cap fibroatheroma (TCFA) (26.1% vs. 17.5%, P=0.026), microchannel (61.8% vs. 34.6%, P<0.001), and cholesterol crystal (38.6% vs. 25.6%, P=0.003). Conclusions: Layered plaque was associated with higher levels of vascular inflammation and plaque vulnerability, which might play an important role in plaque progression.

Abstract 18432: Lipoprotein(a) is Associated With Long-Term Plaque Progression, Pericoronary Inflammation and High-Risk Plaque on Serial Coronary CT Angiography

Background This study investigated the effect of lipoprotein(a) (Lp[a]) on long-term plaque progression, high-risk plaque (HRP) and pericoronary adipose tissue attenuation (PCATa) in patients suspected of coronary artery disease. Methods: Per-protocol, patients from a coronary CT angiography (CCTA) cohort (Diemen et al., 2021) were invited for repeat CCTA imaging, regardless of symptoms. A total of 299 patients underwent follow-up CCTA imaging with a median scan interval of 10.2 [IQR 8.7-11.2] years. Patients who underwent coronary artery bypass grafting and vessels revascularized by percutaneous coronary intervention were excluded. Scans were analyzed using atherosclerosis-imaging quantitative CCTA (AI-QCT; Cleerly Inc.). The associations between high (Tertile 3; >67 nmol/l) and low Lp(a) (Tertile 1 and 2; ≤67 nmol/l), baseline and follow-up plaque burden and characteristics were evaluated using multivariable regression adjusted for clinical risk factors, statin use and scanner settings. Results: In total, 274 patients were included, mean age was 57±7 years, 42% were women. Patients with high Lp(a) levels had higher volumes of percent atheroma volume (PAV) at baseline and follow-up and higher rate of plaque progression (Figure 1A). The difference in PAV caused by high Lp(a) versus low Lp(a) patients was similar to the effect of a 12-year age difference. At baseline, patients in the highest tertile of Lp(a) levels had a higher prevalence of both HRP (OR 2.24; p=0.009) and above-median right coronary artery PCATa (OR 1.76; p=0.049). Finally, patients with high Lp(a) levels had a twofold higher incidence of major adverse cardiovascular events (MACE; Figure 1B; p=0.044). Conclusion: Patients with high Lp(a) levels had increased coronary plaque burden, increased prevalence of high-risk plaque and pericoronary inflammation as well as increased plaque progression leading to an increased incidence of MACE throughout 10-year follow-up.

Abstract 11734: Allopurinol & Plaque Stabilization in Patients With Acute Coronary Syndrome: A Randomized Clinical Trial

Background: Allopurinol, a xanthine inhibitor that lowers uric acid (UA) concentration, has been proven to reduce inflammation and oxidative stress in patients with cardiovascular disease. However, it is unknown whether these beneficial effects translate into favorable plaque modification in acute coronary syndromes (ACS). Aims: This study aimed to investigate whether allopurinol therapy could improve plaque stabilization in ACS patients using coronary computed tomography angiography (CCTA). Methods: This was a prospective, single-center, randomized, double-blind clinical trial began in March 2019 (clinical trial.gov identifier NCT03745729). A total of 162 acute coronary syndromes (ACS) patients aged 18-80 years with a blood level of high-sensitivity C-reactive protein (hsCRP) > 2 mg/L were included. The subjects were randomly assigned in a 1:1 ratio to receive either allopurinol sustained-release capsules (at a dose of 0.25 g once daily) or placebo for 12 months. The primary efficacy endpoint was the change in low-attenuation plaque volume (LAPV) from baseline to the 12-month follow-up. Results: Among 162 patients, 54 in allopurinol group and 51 in placebo group completed the study. There were no significant differences between the allopurinol and placebo groups in terms of baseline data for age (58.5±10.2 years vs. 56.8±10.0 years, P=0.392) and sex (male/female, 40/14 vs. 40/11, P=0.600). The median follow-up duration was 14 months in both groups. Compared with placebo, allopurinol therapy did not significantly alter LAPV (-13.4±3.7% vs. -17.8±3.6%, P=0.390), intermediate attenuation plaque volume (-16.1±3.0% vs. -16.2±2.9%, P=0.992), dense calcified plaque volume (12.2±13.7% vs. 9.7±13.0%, P=0.894), total atheroma volume (-15.2±3.2% vs. -16.4±3.1%, P=0.785), remodeling index (2.0±3.9% vs. 5.4±3.8%, P=0.536) or hsCRP levels (-73.6 [17.9-91.6] % vs. -81.2 [47.7-95.4] %, P=0.286). Conclusions: Our findings suggest, for the first time, that allopurinol therapy does not improve atherosclerotic plaque instability or inflammation in ACS.

An anti-inflammatory Glyburide-loaded nanoghost for atherosclerosis therapy: A red blood cell based bio-mimetic strategy

Inflammation control is becoming a critical strategy for atherosclerosis management, because inflammation is involved in plaque progression. In this regard, a biomimetic strategy using cell membrane-coated nanoparticles has some promising advantages. In the study, a RBC membrane-based nanoghost containing Glyburide (Glibenclamide) was prepared using an extrusion method. The hydrodynamic size and zeta potential of the nanoghost were changed compared to PLGA nanoparticles. In addition, a nanoghost with a diameter and shell size of 125 nm and 8.3 nm was obtained based on the TEM measurement. The fabricated nanoghost was not only hemocompatible but also was biocompatible, showing no significant induction of apoptosis. According to RT-PCR assay, the expression levels of inflammatory genes including NLRP3, IL-1β, IL-18 caspase1, 8 and 9 were decreased. In accordance with in vitro anti-inflammation properties, total foam cells, total surface area in tunica intima and population of CD14+ cells were decreased in the rabbit model of atherosclerosis upon nanoghost treatment, compared to positive control. Furthermore, macrophages in aorta sections exhibited M1 to M2 polarization. In general, the development of Glyburide-loaded nanoghost can be considered as a potential therapeutic for controlling the progression and inflammation of atherosclerotic plaque.

Effect of argon plasma abutment activation on soft tissue healing: RCT with histological assessment.

To assess the peri-implant soft tissue profiles between argon plasma treatment (PT) and non-treated (NPT) healing abutments by comparing clinical and histological parameters 2 months following abutment placement. Thirty participants were randomly assigned to argon-plasma treatment abutments group (PT) or non-treated abutments (NPT) group. Two months after healing abutment placement, soft peri-implant tissues and abutment were harvested, and histological and clinical parameters including plaque index, bleeding on probing, and keratinized mucosa diameter (KM) were assessed. Specialized stainings (hematoxylin-eosin and picrocirious red) coupled with immunohistochemistry (vimentin, collagen, and CK10) were performed to assess soft tissue inflammation and healing, and the collagen content keratinization. In addition to standard statistical methods, machine learning algorithms were applied for advanced soft tissue profiling between the test and control groups. PT group showed lower plaque accumulation and inflammation grade (6.71% vs. 13.25%, respectively; p-value 0.02), and more advanced connective tissue healing and integration compared to NPT (31.77% vs. 23.3%, respectively; p = 0.009). In the control group, more expressed keratinization was found compared to the PT group, showing significantly higher CK10 (>47.5%). No differences in KM were found between the groups. PT seems to be a promising protocol for guided peri-implant soft tissue morphogenesis reducing plaque accumulation and inflammation, and stimulating collagen and soft tissue but without effects on epithelial tissues and keratinization.

GM-CSF-activated STAT5A regulates macrophage functions and inflammation in atherosclerosis.

Inhibition of STAT5 was recently reported to reduce murine atherosclerosis. However, the role of STAT5 isoforms, and more in particular STAT5A in macrophages in the context of human atherosclerosis remains unknown. Here, we demonstrate reciprocal expression regulation of STAT5A and STAT5B in human atherosclerotic lesions. The former was highly upregulated in ruptured over stable plaque and correlated with macrophage presence, a finding that was corroborated by the high chromosomal accessibility of STAT5A but not B gene in plaque macrophages. Phosphorylated STAT5 correlated with macrophages confirming its activation status. As macrophage STAT5 is activated by GM-CSF, we studied the effects of its silencing in GM-CSF differentiated human macrophages. STAT5A knockdown blunted the immune response, phagocytosis, cholesterol metabolism, and augmented apoptosis terms on transcriptional levels. These changes could partially be confirmed at functional level, with significant increases in apoptosis and decreases in lipid uptake and IL-6, IL-8, and TNFa cytokine secretion after STAT5A knockdown. Finally, inhibition of general and isoform A specific STAT5 significantly reduced the secretion of TNFa, IL-8 and IL-10 in ex vivo tissue slices of advanced human atherosclerotic plaques. In summary, we identify STAT5A as an important determinant of macrophage functions and inflammation in the context of atherosclerosis and show its promise as therapeutic target in human atherosclerotic plaque inflammation.

Characteristics and evaluation of atherosclerotic plaques: an overview of state-of-the-art techniques.

Atherosclerosis is an important cause of cerebrovascular and cardiovascular disease (CVD). Lipid infiltration, inflammation, and altered vascular stress are the critical mechanisms that cause atherosclerotic plaque formation. The hallmarks of the progression of atherosclerosis include plaque ulceration, rupture, neovascularization, and intraplaque hemorrhage, all of which are closely associated with the occurrence of CVD. Assessing the severity of atherosclerosis and plaque vulnerability is crucial for the prevention and treatment of CVD. Integrating imaging techniques for evaluating the characteristics of atherosclerotic plaques with computer simulations yields insights into plaque inflammation levels, spatial morphology, and intravascular stress distribution, resulting in a more realistic and accurate estimation of plaque state. Here, we review the characteristics and advancing techniques used to analyze intracranial and extracranial atherosclerotic plaques to provide a comprehensive understanding of atheroma.

Polymorphism of cytokine and C-reactive protein genes in patients with psoriasis in the Kemerovo region of Russia

Aim. To study the associations of polymorphisms of IL-1b (rs16944), IL-6 (rs1554606), IL-8 (rs2227306), IL-10 (rs1800896), TNFα (rs361525), CRP (rs1205) genes and their intergenic interactions with the risk of psoriasis development in Kemerovo region residents. Materials and Methods. We examined 170 patients (102 men and 78 women) a clinically established diagnosis of vulgar psoriasis. The average age of patients was 46.2+3.9 years, 165 people (97%) had progressive stage psoriasis. The control group (n=155) included 98 healthy men and 57 women matched by age. Genomic DNA isolated from peripheral blood leukocytes by phenol-chloroform extraction according to the standard protocol was used as material. Logistic regression analysis was performed to assess the role of intergenic interactions in the development of psoriasis. Conclusion. In patients of the Kemerovo region, vulgar psoriasis is associated with minor homozygous genotypes of polymorphic variants of TNFα (rs361525), IL-1b (rs16944), CRP (rs1205) genes. The minor homozygous TNFα (rs361525) genotype has a high odds ratio and is determinant in the development of this form of psoriasis among all genes studied. The major allele and IL-10 genotype (rs1800896) is a disease modifier and affects the clinical course, particularly the development of inflammatory plaques and papules on the lower and upper extremities of patients.

SARS-CoV-2 infection triggers pro-atherogenic inflammatory responses in human coronary vessels

Patients with coronavirus disease 2019 (COVID-19) present increased risk for ischemic cardiovascular complications up to 1 year after infection. Although the systemic inflammatory response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely contributes to this increased cardiovascular risk, whether SARS-CoV-2 directly infects the coronary vasculature and attendant atherosclerotic plaques remains unknown. Here we report that SARS-CoV-2 viral RNA is detectable and replicates in coronary lesions taken at autopsy from severe COVID-19 cases. SARS-CoV-2 targeted plaque macrophages and exhibited a stronger tropism for arterial lesions than adjacent perivascular fat, correlating with macrophage infiltration levels. SARS-CoV-2 entry was increased in cholesterol-loaded primary macrophages and dependent, in part, on neuropilin-1. SARS-CoV-2 induced a robust inflammatory response in cultured macrophages and human atherosclerotic vascular explants with secretion of cytokines known to trigger cardiovascular events. Our data establish that SARS-CoV-2 infects coronary vessels, inducing plaque inflammation that could trigger acute cardiovascular complications and increase the long-term cardiovascular risk.

Inflammatory atherosclerotic plaque identification by SPECT/CT imaging of LFA-1 using [111In] In-DANBIRT in a novel dyslipidemic rat model.

Atherosclerosis is prevalent globally, closely associated with dyslipidemia and other metabolic dysfunction. Early diagnosis of atherosclerosis is challenging due to limited diagnostic capabilities that need to be expanded with animal models with enhanced vascular biology like rats. Our previous research showed [111In] In-DANBIRT has potential as a diagnostic tool for detecting atherosclerosis in mice. The primary aim of the present study is to evaluate [111In] In-DANBIRT in a novel atherosclerotic rat with early- and late-stage atherosclerosis and metabolic disease. We characterized metabolic and body composition differences in these novel dyslipidemic rats under different diets using serum chemistry and dual-energy X-ray absorptiometry (DEXA) scan, respectively. We performed 1-h post-injection in vivo molecular imaging of ApoE knockout, lean Zucker (LZ) male rats at baseline and followed them into 10weeks of either normal or high-fat/cholesterol diet implementation (22weeks of age). We identified significant differences in body composition and metabolic changes in ApoE knockout rats compared to ApoE wildtype rats. Our findings indicate an increased uptake of [111In] In-DANBIRT in ApoE knockout, lean Zucker (LZ) rats, particularly in the descending aorta, a location where early-stage atherosclerosis is commonly found. Our findings, however, also revealed that the ApoE knockout, Zucker diabetic fatty (ZDF) model has high mortality rate, which may be attributed to alterations of critical enzymes involved in regulating metabolism and liver function. Our results are highly encouraging as they demonstrated the potential of [111In] In-DANBIRT to detect early-stage atherosclerosis in rats that might otherwise go unnoticed by other methods, showcasing the high sensitivity of [111In] In-DANBIRT. Our future studies will aim to establish a viable T2D atherosclerosis model in rats with more advanced stages of the disease to further demonstrate the reliability of [111In] In-DANBIRT as a diagnostic tool for patients in all stages of atherosclerosis.

Long-axial field-of-view PET/CT for the assessment of inflammation in calcified coronary artery plaques with [68 Ga]Ga-DOTA-TOC

PurposeInflamed, prone-to-rupture coronary plaques are an important cause of myocardial infarction and their early identification is crucial. Atherosclerotic plaques are characterized by overexpression of the type-2 somatostatin receptor (SST2) in activated macrophages. SST2 ligand imaging (e.g. with [68 Ga]Ga-DOTA-TOC) has shown promise in detecting and quantifying the inflammatory activity within atherosclerotic plaques. However, the sensitivity of standard axial field of view (SAFOV) PET scanners may be suboptimal for imaging coronary arteries. Long-axial field of view (LAFOV) PET/CT scanners may help overcome this limitation. We aim to assess the ability of [68 Ga]Ga-DOTA-TOC LAFOV-PET/CT in detecting calcified, SST2 overexpressing coronary artery plaques.MethodsIn this retrospective study, 108 oncological patients underwent [68 Ga]Ga-DOTA-TOC PET/CT on a LAFOV system. [68 Ga]Ga-DOTA-TOC uptake and calcifications in the coronary arteries were evaluated visually and semi-quantitatively. Data on patients’ cardiac risk factors and coronary artery calcium score were also collected. Patients were followed up for 21.5 ± 3.4 months.ResultsA total of 66 patients (61.1%) presented with calcified coronary artery plaques. Of these, 32 patients had increased [68 Ga]Ga-DOTA-TOC uptake in at least one coronary vessel (TBR: 1.65 ± 0.53). Patients with single-vessel calcifications showed statistically significantly lower uptake (SUVmax 1.10 ± 0.28) compared to patients with two- (SUVmax 1.31 ± 0.29, p < 0.01) or three-vessel calcifications (SUVmax 1.24 ± 0.33, p < 0.01). There was a correlation between coronary artery calcium score (CACS) and [68 Ga]Ga-DOTA-TOC uptake, especially in the LAD (p = 0.02). Stroke and all-cause death occurred more frequently in patients with increased [68 Ga]Ga-DOTA-TOC uptake (15.63% vs. 0%; p:0.001 and 21.88% vs. 6.58%; p: 0.04, respectively) during the follow-up period.Conclusion[68 Ga]Ga-DOTA-TOC as a marker for the macrophage activity can reveal unknown cases of inflamed calcified coronary artery plaques using a LAFOV PET system. [68 Ga]Ga-DOTA-TOC uptake increased with the degree of calcification and correlated with higher risk of stroke and all-cause death. [68 Ga]Ga-DOTA-TOC LAFOV PET/CT may be useful to assess patients’ cardiovascular risk.

Lysyl oxidase-dependent extracellular matrix crosslinking modulates calcification in atherosclerosis and aortic valve disease

Extracellular matrix (ECM) is an active player in cardiovascular calcification (CVC), a major public health issue with an unmet need for effective therapies. Lysyl oxidase (LOX) conditions ECM biomechanical properties; thus, we hypothesized that LOX might impact on mineral deposition in calcific aortic valve disease (CAVD) and atherosclerosis. LOX was upregulated in calcified valves from two cohorts of CAVD patients. Strong LOX immunostaining was detected surrounding calcified foci in calcified human valves and atherosclerotic lesions colocalizing with RUNX2 on valvular interstitial cells (VICs) or vascular smooth muscle cells (VSMCs). Both LOX secretion and organized collagen deposition were enhanced in calcifying VICs exposed to osteogenic media. β-aminopropionitrile (BAPN), an inhibitor of LOX, attenuated collagen deposition and calcification. VICs seeded onto decellularized matrices from BAPN-treated VICs calcified less than cells cultured onto control scaffolds; instead, VICs exposed to conditioned media from cells over-expressing LOX or cultured onto LOX-crosslinked matrices calcified more. Atherosclerosis was induced in WT and transgenic mice that overexpress LOX in VSMC (TgLOXVSMC) by AAV-PCSK9D374Y injection and high-fat feeding. In atherosclerosis-challenged TgLOXVSMC mice both atherosclerosis burden and calcification assessed by near-infrared fluorescence (NIRF) imaging were higher than in WT mice. These animals also exhibited larger calcified areas in atherosclerotic lesions from aortic arches and brachiocephalic arteries. Moreover, LOX transgenesis exacerbated plaque inflammation, and increased VSMC cellularity, the rate of RUNX2-positive cells and both connective tissue content and collagen cross-linking. Our findings highlight the relevance of LOX in CVC and postulate this enzyme as a potential therapeutic target for CVC.

Effects of renin-angiotensin-aldosterone-system inhibitors on coronary atherosclerotic plaques: The PARADIGM registry

Background and aimsInhibition of Renin-Angiotensin-Aldosterone-System (RAAS) has been hypothesized to improve endothelial function and reduce plaque inflammation, however, their impact on the progression of coronary atherosclerosis is unclear. We aim to study the effects of RAAS inhibitor on plaque progression and composition assessed by serial coronary CT angiography (CCTA). MethodsWe performed a prospective, multinational study consisting of a registry of patients without history of CAD, who underwent serial CCTAs. Patients using RAAS inhibitors were propensity matched to RAAS inhibitor naïve patients based on clinical and CCTA characteristics at baseline. Atherosclerotic plaques in CCTAs were quantitatively analyzed for percent atheroma volume (PAV) according to plaque composition. Interactions between RAAS inhibitor use and baseline PAV on plaque progression were assessed in the unmatched cohort using a multivariate linear regression model. ResultsOf 1248 patients from the registry, 299 RAAS inhibitor taking patients were matched to 299 RAAS inhibitor naïve patients. Over a mean interval of 3.9 years, there was no significant difference in annual progression of total PAV between RAAS inhibitor naïve vs taking patients (0.75 vs 0.79%/year, p = 0.66). With interaction testing in the unmatched cohort, however, RAAS inhibitor use was significantly associated with lower non-calcified plaque progression (Beta coefficient −0.100, adjusted p = 0.038) with higher levels of baseline PAV. ConclusionsThe use of RAAS inhibitors over a period of nearly 4 years did not significantly impact on total atherosclerotic plaque progression or various plaque components. However, interaction testing to assess the differential effect of RAAS inhibition based on baseline PAV suggested a significant decrease in progression of non-calcified plaque in patients with a higher burden of baseline atherosclerosis, which should be considered hypothesis generating.

Moxibustion's protective role against atherosclerosis: Inhibition of Ca2+ overload-triggered oxidative stress and inflammatory response via P2Y12/PI3K/AKT pathway.

This study aims to investigate the protective mechanism of moxibustion in combating atherosclerosis (AS). Apolipoprotein E (ApoE)-deficient mice, aged 8 weeks, were randomly assigned into four groups: the model group (n = 6), SC79 group (n = 6), moxibustion group (n = 6), and moxibustion+SC79 group (n = 6). All mice were fed with a high-fat diet (HFD). Concurrently, 8-week-old C57BL/6 mice of the same genetic background were utilized as the control group (n = 6) and were given a regular diet. Macrophages were isolated via flow cytometry. The intracellular Ca2+ expression in macrophages was evaluated, and aortic plaques were quantitatively assessed through en face oil red O and Masson staining. The presence of macrophages and smooth muscle cells in AS plaques was determined by MAC-3 and α-smooth muscle actin (α-SMA) immunohistochemistry. The relative fluorescence intensity of nuclear factor-κB (NF-κB) in macrophages was identified by immunofluorescence staining. The expressions of proteins related to the P2Y12/phosphatidylinositol 3-hydroxy kinase (PI3K)/protein kinase B (AKT) signaling pathway were examined by Western blotting. Moxibustion reduced free Ca2+ expression in macrophage cytoplasm, inhibiting Ca2+ influx and oxidative stress. Significant reductions in atherosclerotic plaque formation and inflammation markers, including TNF-α and IL-1β, were noted in the moxibustion group. Moxibustion modulated the P2Y12/PI3K/AKT pathway, impacting various inflammatory and oxidative stress-related proteins. Introduction of the AKT activator SC79 counteracted moxibustion's benefits, highlighting the P2Y12/PI3K/AKT pathway's central role. Moxibustion, through the P2Y12/PI3K/AKT signaling pathway, can inhibit Ca2+ overload-induced oxidative stress and inflammatory response, decrease macrophage infiltration, and increase the content of smooth muscle cells and collagen, thereby exerting a protective effect against AS.

Modulating Plaque Inflammation via Targeted mRNA Nanoparticles for the Treatment of Atherosclerosis.

Atherosclerosis is a common pathology present in many cardiovascular diseases. Although the current therapies (including statins and inhibitors of the serine protease PCSK9) can effectively reduce low-density lipoprotein (LDL) cholesterol levels to guideline-recommended levels, major adverse cardiovascular events still occur frequently. Indeed, the subendothelial retention of lipoproteins in the artery wall triggers multiple events of inflammation in macrophages and is a major contributor to the pathological progression of atherosclerosis. It has been gradually recognized that modulating inflammation is, therefore, an attractive avenue to forestall and treat atherosclerosis and its complications. Unfortunately, challenges with specificity and efficacy in managing plaque inflammation have hindered progress in atherosclerosis treatment. Herein, we report an NP-mediated mRNA therapeutic approach to target atherosclerotic lesional macrophages, modulating inflammation in advanced atherosclerotic lesions for the treatment of atherosclerosis. We demonstrated that the targeted NPs containing IL-10 mRNA colocalized with M2-like macrophages and induced IL-10 production in atherosclerotic plaques following intravenous administration to Western diet (WD)-fed Ldlr-/- mice. Additionally, the lesions showed a significantly alleviated inflammatory response, as evidenced by reduced oxidative stress and macrophage apoptosis, resulting in decreased lipid deposition, diminished necrotic areas, and increased fiber cap thickness. These results demonstrate the successful delivery of mRNA therapeutics to macrophage-enriched plaques in a preclinical model of advanced atherosclerosis, showing that this targeted NP inflammation management approach has great potential for translation into a wide range of clinical applications.