Plasma ceramides as biomarkers for microvascular disease and clinical outcomes in diabetes and myocardial infarction.

BACKGROUND: Ceramides have recently been identified as novel biomarkers associated with diabetes mellitus (DM) and major adverse cardiac and cerebrovascular events (MACCE). This study aims to explore their utility in diagnosing microvascular disease. METHODS: This study prospectively enrolled 309 patients from 2018 to 2020 into three groups: healthy controls (Group 1, N = 51), DM patients without acute myocardial infarction (AMI) (Group 2, N = 150), and DM patients with AMI (Group 3, N = 108). We assessed outcomes using stress perfusion cardiac magnetic resonance (CMR) imaging for coronary microvascular disease (CMD) (Outcome 1), retinography for retinal microvascular disease (RMD) (Outcome 2), both CMD and RMD (Outcome 3), and absence of microvascular disease (w/o MD) (outcome 4). We evaluated the classification performance of ceramides using receiver operating characteristic (ROC) analysis and multiple logistic regression. 11-ceramide panel previously identified by our research group as related to macrovascular disease were used. RESULTS: Average glycated hemoglobin (HbA1c) values were 5.1% in Group 1, 8.3% in Group 2, and 7.6% in Group 3. Within the cohort, CMD was present in 59.5% of patients, RMD in 25.8%, both CMD and RMD in 18.8%, and w/o MD in 38.5%. The AUC values for the reference ceramide ratios were as follows: CMD at 0.66 (p = 0.012), RMD at 0.61 (p = 0.248), CMD & RMD at 0.64 (p = 0.282), and w/o MD at 0.67 (p = 0.010). In contrast, the AUC values using 11-ceramide panel showed significant improvement in the outcomes prediction: CMD at 0.81 (p = 0.001), RMD at 0.73 (p = 0.010), CMD & RMD at 0.73 (p = 0.04), and w/o MD at 0.83 (p = 0.010). Additionally, the plasma concentration of C14.0 was notably higher in the w/o MD group (p < 0.001). CONCLUSIONS: Plasma ceramides serve as potential predictors for health status and microvascular disease phenotypes in diabetic patients.

Integrated metabolomics and metallomics analyses in acute coronary syndrome patients.

Acute coronary syndrome (ACS) is the leading cause of morbidity and mortality. Accurate risk prediction in ACS patients is critically important for helping clinicians make therapeutic decisions, such as recommending a more aggressive intervention and intensive follow-up. However, risk stratification in ACS patients remains challenging, and the identification of novel predictors is necessary for improving the prognostic prediction in ACS patients. We employed metallomics and untargeted metabolomics approaches to discover new biomarkers from the plasma samples of 20 ACS patients and 20 non-ACS patients. We identified metabolic changes related to lysophosphatidylcholines, caffeine, glycolysis, tryptophan and sphingomyelin metabolism (p value <0.05) that were perturbed in the ACS patients. Moreover, circulating metal elements, including Mg, Ca, K, Zn, Ni, Ga and In (p value <0.05), were altered in the ACS patients versus the controls. These changes suggest possible changes in cell membrane permeability and rigidity in ACS patients.

Development of bioanalytical assays for variegin, a peptide-based bivalent direct thrombin inhibitor.

AIM: Variegin is an anticoagulant peptide that will be tested in porcine models of percutaneous coronary intervention. We developed three bioanalytical assays for variegin quantitation and utilized these methods to evaluate pharmacokinetics of variegin in pigs. Results & methodology: The LC-MS/MS, thrombin amidolytic and modified thrombin time assays had a quantitation range of 21.6-5541.7, 10.8-5541.7 and 5.4-5541.7 nM in human plasma, respectively. The elimination half-lives obtained using the LC-MS/MS, modified thrombin time and thrombin amidolytic assays were 52.3 ± 4.4, 50.4 ± 5.9 and 67.7 ± 6.3 min, respectively. CONCLUSION: We developed three bioanalytical assays for a novel direct thrombin inhibitor, variegin. The thrombin time assay is optimized for variegin quantitation during future porcine studies and clinical trials.

Highly sensitive and quantitative human thrombospondin-1 detection by an M55 aptasensor and clinical validation in patients with atherosclerotic disease.

Aptamer-based biosensors (aptasensor) are powerful tools for rapid and sensitive biomarker detection. In this study, we report a DNA aptamer probe evolved from cell-SELEX that can recognize thrombospondin-1 protein in human plasma samples. The KD value of the aptamer M55 binding to thrombospondin-1 was determined as 0.5 ± 0.2 µM with an R(2) of 0.9144. A horseradish peroxidase-linked short oligo was complementarily bound onto the 3' end of the aptamer sequence to facilitate the 'smart' design of an M55-aptasensor for quantifying thrombospondin-1 protein in plasma samples. The limit of detection was 6.96 fM. Thrombospondin-1 is a glycoprotein with multiple biological functions, including inflammation, platelet aggregation and endothelial cell apoptosis, and is involved in the pathology of atherosclerosis. In total, 118 plasma subjects were analyzed by using the aptasensor measurement with 1 µL sample volume and 5 min incubation time. The thrombospondin-1 concentrations in ST-Elevation Myocardial Infarction patients with severe atherosclerotic plaque burden were statistically significantly higher than in the healthy volunteers without atherosclerosis conditions, suggesting that thromboposnidn-1 is a potential plasma biomarker for atherosclerosis progression.

Impact of angiogenic therapy in the treatment of critical lower limb ischemia in an animal model.

Angiogenic therapies for critical limb ischemia were tested in a mouse model. The mice were anesthetized and their femoral arteries were ligated. The animals were treated with bone marrow mononuclear cells (BMMCs) alone, BMMCs combined with plasmid vector encoding granulocyte macrophage colony-stimulating factor (GM-CSF), received no treatment, or no intervention (controls). The degree of ischemia was monitored for 4 weeks using a visual scale. Muscle atrophy and strength were assessed at 4 weeks postoperatively; the mice were then killed. In treated animals, total necrosis of the limb was not found, the weight of the gastrocnemius and quadriceps muscles was significantly higher, functional ability and tissue regeneration were significantly increased, and muscle impairment and adipocyte presence were significantly reduced compared with untreated animals. At inducing angiogenesis, the BMMCs alone was more effective than BMMCs combined with plasmid vector encoding GM-CSF. Treated animals showed increased angiogenesis compared with ischemic untreated ones.

Treatment of mouse limb ischemia with an integrative hypoxia-responsive vector expressing the vascular endothelial growth factor gene.

Constitutive vascular endothelial growth factor (VEGF) gene expression systems have been extensively used to treat peripheral arterial diseases, but most of the results have not been satisfactory. In this study, we designed a plasmid vector with a hypoxia-responsive element sequence incorporated into it with the phiC31 integrative system (pVHAVI) to allow long-term VEGF gene expression and to be activated under hypoxia. Repeated activations of VEGF gene expression under hypoxia were confirmed in HEK293 and C2C12 cells transfected with pVHAVI. In limb ischemic mice, the local administration of pVHAVI promoted gastrocnemius mass and force recovery and ameliorated limb necrosis much better than the group treated with hypoxia-insensitive vector, even this last group had produced more VEGF in muscle. Histological analyses carried out after four weeks of gene therapy showed increased capillary density and matured vessels, and reduced number of necrotic cells and fibrosis in pVHAVI treated group. By our study, we demonstrate that the presence of high concentration of VEGF in ischemic tissue is not beneficial or is less beneficial than maintaining a lower but sufficient and long-term concentration of VEGF locally.

Treatment of adult MPSI mouse brains with IDUA-expressing mesenchymal stem cells decreases GAG deposition and improves exploratory behavior.

BACKGROUND: Mucopolysaccharidosis type I (MPSI) is caused by a deficiency in alpha-L iduronidase (IDUA), which leads to lysosomal accumulation of the glycosaminoglycans (GAGs) dermatan and heparan sulfate. While the currently available therapies have good systemic effects, they only minimally affect the neurodegenerative process. Based on the neuroprotective and tissue regenerative properties of mesenchymal stem cells (MSCs), we hypothesized that the administration of MSCs transduced with a murine leukemia virus (MLV) vector expressing IDUA to IDUA KO mouse brains could reduce GAG deposition in the brain and, as a result, improve neurofunctionality, as measured by exploratory activity. METHODS: MSCs infected with an MLV vector encoding IDUA were injected into the left ventricle of the brain of 12- or 25-month-old IDUA KO mice. The behavior of the treated mice in the elevated plus maze and open field tests was observed for 1 to 2 months. Following these observations, the brains were removed for biochemical and histological analyses. RESULTS: After 1 or 2 months of observation, the presence of the transgene in the brain tissue of almost all of the treated mice was confirmed using PCR, and a significant reduction in GAG deposition was observed. This reduction was directly reflected in an improvement in exploratory activity in the open field and the elevated plus maze tests. Despite these behavioral improvements and the reduction in GAG deposition, IDUA activity was undetectable in these samples. Overall, these results indicate that while the initial level of IDUA was not sustainable for a month, it was enough to reduce and maintain low GAG deposition and improve the exploratory activity for months. CONCLUSIONS: These data show that gene therapy, via the direct injection of IDUA-expressing MSCs into the brain, is an effective way to treat neurodegeneration in MPSI mice.

Comparação das vias radial e femoral nas intervenções coronárias percutâneas: resultados do registro TotalCor / Comparison of radial vs. femoral access in percutaneous coronary interventions: outcomes of the TotalCor registry

Introdução: A intervenção coronária percutânea (ICP) por via radial ainda é pouco utilizada em nosso meio. O objetivo do presente estudo foi avaliar a prevalência e os resultados da ICP por via radial, comparada à via femoral, em uma população do mundo real. Métodos: Registro unicêntrico, com 507 pacientes consecutivos submetidos a ICP pelas vias radial (n = 121) e femoral (n = 386), de acordo com a escolha do operador. Resultados: Os pacientes que utilizaram a via radial (23,9%) eram mais frequentemente do sexo masculino (78,5% vs. 69,9%; P = 0,07) e tabagistas (19,8% vs. 11,7%; P = 0,02), com maior prevalência de lesões uniarteriais (59,5% vs. 46,4%), tipo A/B1 (39% vs. 28,4%) e com função ventricular preservada (87,1% vs. 73%; P < 0,01). Nesse grupo foram utilizados stents de maior diâmetro e menor comprimento. O sucesso do procedimento foi elevado (97,3% vs. 96,3%; P = 0,56) e a incidência de óbito foi baixa, não diferindo entre os grupos (0,8% vs. 0,8%; P = 0,96), assim como as taxas de infarto do miocárdio (2,5% vs. 2,1%; P = 0,73). Não ocorreram revascularizações do vaso-alvo de urgência. Os pacientes tratados pela via radial permaneceram menos tempo internados (1 dia vs. 2 dias; P = 0,02) e não apresentaram complicações vasculares (0 vs. 3,4%; P = 0,045). Conclusões: A utilização da ICP por via radial representa o dobro da média nacional na instituição em que o estudo foi realizado, e a escolha de pacientes para essa técnica trouxe resultados do procedimento equivalentes aos da via femoral, nenhuma complicação vascular, e reduziu à metade o tempo de internação hospitalar.

BACKGROUND: In our country radial access is still underused in percutaneous coronary interventions (PCI). The objective of this study was to evaluate the prevalence and compare radial to femoral vascular access for PCI in a real-world population. METHODS: Single center registry, with 507 consecutive patients undergoing PCI by radial (n = 121) and femoral (n = 386) access, according to the operator's choice. RESULTS: Patients using radial access (23.9%) were more often male (78.5% vs. 69.9%; P = 0.07) and smokers (19.8% vs. 11.7%; P = 0.02), had a higher prevalence of single-vessel disease (59.5% vs. 46.4%), type A/B1 (39% vs. 28.4%) lesions and had preserved ventricular function (87.1% vs. 73%; P < 0.01). Larger diameter and shorter stents were used in this group. Procedure success was high (97.3% vs. 96.3%; P = 0.56), the incidence of death was low and was not different between groups (0.8% vs. 0.8%; P = 0.96), as well as myocardial infarction rates (2.5% vs. 2.1%; P = 0.73). There were no urgent target-vessel revascularizations. Patients treated by the radial approach had a shorter hospitalization period (1 day vs. 2 days; P = 0.02) and did not have vascular complications (0 vs. 3.4%; P = 0.045). CONCLUSIONS: The use of radial access for PCI in our institution is twice the national average and the choice of patients for this technique provided similar results to those obtained by the femoral approach, no vascular complications and halved patients' average stay in hospital.

Granulocyte-macrophage colony-stimulating factor gene based therapy for acute limb ischemia in a mouse model.

BACKGROUND: Granulocyte-colony-stimulating factor (GM-CSF) is a pleiotropic factor for hematopoiesis that stimulates myeloblasts, monoblasts and mobilization of bone marrow stem cells. Therefore, the GM-CSF gene is a potential candidate for vessel formation and tissue remodeling in the treatment of ischemic diseases. METHODS: A new mouse limb ischemia was established by surgery and gene transfer was performed by injection of 100 microg of a plasmid carrying GM-CSF. Muscle force and weight, histology, capillary density, circulating stem cells and monocytes were determined after 3-4 weeks. RESULTS: More than 60% of nontreated ischemic animals showed gangrene below the heel after 4 weeks, whereas the GM-CSF gene-treated animals showed only darkening of nails or toes. These animals demonstrated a full recovery of the affected muscles in terms of weight, force and muscle fiber structure, but the muscles of nontreated ischemic animals lost approximately 50% weight, 86% force and their regular structure. When the GM-CSF gene was injected into the contralateral limb, only partial loss was observed, demonstrating a distant effect of GM-CSF. The capillary density in the GM-CSF-treated group was 52% higher in relation to the nontreated group. Blood analysis by flow cytometry showed that the GM-CSF-treated group had 10-20% higher levels of circulating monocytes and Sca-1(+). CONCLUSIONS: We conclude that the direct administration of GM-CSF gene in limb ischemia had a strong therapeutic effect because it promoted the recovery of muscle mass, force and structure by mobilizing therapeutic cells and augmenting the number of vessels.

Long-term effects for acute phase myocardial infarct VEGF165 gene transfer cardiac extracellular matrix remodeling.

BACKGROUND: Cardiac remodeling is ultimately regulated by components of the extracellular matrix (ECM). We investigated the important role that growth factors play in the regulation of ECM remodeling that occurs as a consequence of myocardium damage. METHODS AND RESULTS: Rats were submitted to the ligation of the left anterior coronary artery and pcDNA3-vascular endothelial growth factor (VEGF)(165) was immediately injected intramyocardially in the treated group. The animals were divided into large size myocardium infarction (LMI) and small size myocardium infarction, with or without gene transfer. The plasmid-containing DNA encoding VEGF(165) was injected into the cardiac muscle and its effect was observed on the ECM components. Glycosaminoglycans were identified and quantified by agarose gel based electrophoresis and ELISA as well as immunocytochemistry to examine specific cathepsin B, heparanase, and syndecan-4 changes. The amounts of hyaluronic acid (HA; p < 0.005), DS, chondroitin sulfate, and heparan sulfate (p < 0.001) were significantly increased in the LMI treated group in comparison to the other groups, which correlates with the decrease in the expression of heparanase. A decrease in the molecular mass of HA was found in the scar tissue of treated group. CONCLUSIONS: The data obtained strongly support the idea that changes in the ECM and its components are important determinants of cardiac remodeling after myocardium infarct and may be essential for inflammatory response and attempt to stabilize the damage and provide a compensatory mechanisms to maintain cardiac output since the ECM components analyzed are involved with angiogenesis, cell proliferation and differentiation.