Carbonic anhydrase activation is associated with worsened pathological remodeling in human ischemic diabetic cardiomyopathy.

BACKGROUND: Diabetes mellitus (DM) has multifactorial detrimental effects on myocardial tissue. Recently, carbonic anhydrases (CAs) have been shown to play a major role in diabetic microangiopathy but their role in the diabetic cardiomyopathy is still unknown. METHODS AND RESULTS: We obtained left ventricular samples from patients with DM type 2 (DM-T2) and nondiabetic (NDM) patients with postinfarct heart failure who were undergoing surgical coronary revascularization. Myocardial levels of CA-I and CA-II were 6- and 11-fold higher, respectively, in DM-T2 versus NDM patients. Elevated CA-I expression was mainly localized in the cardiac interstitium and endothelial cells. CA-I induced by high glucose levels hampers endothelial cell permeability and determines endothelial cell apoptosis in vitro. Accordingly, capillary density was significantly lower in the DM-T2 myocardial samples (mean±SE=2152±146 versus 4545±211/mm(2)). On the other hand, CA-II was mainly upregulated in cardiomyocytes. The latter was associated with sodium-hydrogen exchanger-1 hyperphosphorylation, exaggerated myocyte hypertrophy (cross-sectional area 565±34 versus 412±27 μm(2)), and apoptotic death (830±54 versus 470±34 per 10(6) myocytes) in DM-T2 versus NDM patients. CA-II is activated by high glucose levels and directly induces cardiomyocyte hypertrophy and death in vitro, which are prevented by sodium-hydrogen exchanger-1 inhibition. CA-II was shown to be a direct target for repression by microRNA-23b, which was downregulated in myocardial samples from DM-T2 patients. MicroRNA-23b is regulated by p38 mitogen-activated protein kinase, and it modulates high-glucose CA-II-dependent effects on cardiomyocyte survival in vitro. CONCLUSIONS: Myocardial CA activation is significantly elevated in human diabetic ischemic cardiomyopathy. These data may open new avenues for targeted treatment of diabetic heart failure

MicroRNA-133 controls vascular smooth muscle cell phenotypic switch in vitro and vascular remodeling in vivo

RATIONALE: MicroRNA (miR)-1 and -133 play a crucial role in skeletal and cardiac muscle biology and pathophysiology. However, their expression and regulation in vascular cell physiology and disease is currently unknown. OBJECTIVE: The aim of the present study was to evaluate the role, if any, of miR-1 and miR-133 in vascular smooth muscle cell (VSMC) phenotypic switch in vitro and in vivo. METHODS AND RESULTS: We demonstrate here that miR-133 is robustly expressed in vascular smooth muscle cells (VSMCs) in vitro and in vivo, whereas miR-1 vascular levels are negligible. miR-133 has a potent inhibitory role on VSMC phenotypic switch in vitro and in vivo, whereas miR-1 does not have any relevant effect per se. miR-133 expression is regulated by extracellular signal-regulated kinase 1/2 activation and is inversely correlated with VSMC growth. Indeed, miR-133 decreases when VSMCs are primed to proliferate in vitro and following vascular injury in vivo, whereas it increases when VSMCs are coaxed back to quiescence in vitro and in vivo. miR-133 loss- and gain-of-function experiments show that miR-133 plays a mechanistic role in VSMC growth. Accordingly, adeno-miR-133 reduces but anti-miR-133 exacerbates VSMC proliferation and migration in vitro and in vivo. miR-133 specifically suppresses the transcription factor Sp-1 expression in vitro and in vivo and through Sp-1 repression regulates smooth muscle gene expression. CONCLUSIONS: Our data show that miR-133 is a key regulator of vascular smooth muscle cell phenotypic switch in vitro and in vivo, suggesting its potential therapeutic application for vascular diseases

Inhibition of miR-92a increases endothelial proliferation and migration in vitro as well as reduces neointimal proliferation in vivo after vascular injury

The role of miR-92a on vascular remodelling after injury is currently unknown. Thus, the aim of the present study was to evaluate the role of miR-92a on rat endothelial and vascular smooth muscle cells proliferation and migration in vitro as well as after balloon injury or arterial stenting in vivo. MiR-92a was highly expressed in RAO-ECs and vascular endothelium, but not in RAOSMCs or medial smooth muscle as assessed by real-time RT-PCR. Importantly, BrdU incorporation and wound healing assay provide evidence that functional inhibition of miR-92a resulted in an increased RAO-ECs proliferation and migration, but had no effect on RAO-SMCs proliferation or migration in vitro. Immunoblotting analysis revealed an increased phosphorylation of ERK1/2, JNK/ SAPK as well as eNOS and phospho-eNOS increased expression level in RAO-ECs as a consequence of miR-92a inhibition. Using gain and loss of function experiments, we showed that miR-92a modulates regulation of KLF4 and MKK4 expression level in endothelial cells. Finally, in vivo administration of antagomiR-92a significantly enhanced re-endothelialization in injured carotid arteries and reduced neointimal formation after balloon injury or arterial stenting. These data provide the first evidence that inhibition of miR-92a may represent a novel strategy to improve endothelial regeneration and reduce restenosis after vascular injury. © Springer-Verlag 2012

Empagliflozin prevents doxorubicin-induced myocardial dysfunction

none11noBACKGROUND: Empagliflozin showed efficacy in controlling glycaemia, leading to reductions in HbA1c levels, weight loss and blood pressure, compared to standard treatment. Moreover, the EMPA-REG OUTCOME trial demonstrated a 14% reduction of major adverse cardiovascular events (MACE), a 38% reduction in cardiovascular (CV) death and a 35% reduction in the hospitalization rate for heart failure (HF). These beneficial effect on HF were apparently independent from glucose control. However, no mechanistic in vivo studies are available to explain these results, yet. We aimed to determine the effect of empagliflozin on left ventricular (LV) function in a mouse model of doxorubicin-induced cardiomyopathy (DOX-HF). METHODS: Male C57Bl/6 mice were randomly assigned to the following groups: controls (CTRL, n = 7), doxorubicin (DOX, n = 14), DOX plus empagliflozin (DOX + EMPA, n = 14), or DOX plus furosemide (DOX + FURO group, n = 7). DOX was injected intraperitoneally. LV function was evaluated at baseline and after 6 weeks of treatment using high-resolution echocardiography with 2D speckle tracking (Vevo 2100). Histological assessment was obtained using Haematoxylin and Eosin and Masson's Goldner staining. RESULTS: A significant decrease in both systolic and diastolic LV function was observed after 6 weeks of treatment with doxorubicin. EF dropped by 32% (p = 0.002), while the LS was reduced by 42% (p < 0.001) and the CS by 50% (p < 0.001). However, LV function was significantly better in the DOX + EMPA group, both in terms of EF (61.30 ± 11% vs. 49.24 ± 8%, p = 0.007), LS (- 17.52 ± 3% vs. - 13.93 ± 5%, p = 0.04) and CS (- 25.75 ± 6% vs. - 15.91 ± 6%, p < 0.001). Those results were not duplicated in the DOX + FURO group. Hearts from the DOX + EMPA group showed a 50% lower degree of myocardial fibrosis, compared to DOX mice (p = 0.03). No significant differences were found between the DOX + FURO and the DOX group (p = 0.103). CONCLUSION: Empagliflozin attenuates the cardiotoxic effects exerted by doxorubicin on LV function and remodelling in nondiabetic mice, independently of glycaemic control. These findings support the design of clinical studies to assess their relevance in a clinical setting.noneSabatino J.; De Rosa S.; Tamme L.; Iaconetti C.; Sorrentino S.; Polimeni A.; Mignogna C.; Amorosi A.; Spaccarotella C.; Yasuda M.; Indolfi C.Sabatino, J.; De Rosa, S.; Tamme, L.; Iaconetti, C.; Sorrentino, S.; Polimeni, A.; Mignogna, C.; Amorosi, A.; Spaccarotella, C.; Yasuda, M.; Indolfi, C

Hindlimb Ischemia Impairs Endothelial Recovery and Increases Neointimal Proliferation in the Carotid Artery

Peripheral ischemia is associated with higher degree of endothelial dysfunction and a worse prognosis after percutaneous coronary interventions (PCI). However, the role of peripheral ischemia on vascular remodeling in remote districts remains poorly understood. Here we show that the presence of hindlimb ischemia significantly enhances neointima formation and impairs endothelial recovery in balloon-injured carotid arteries. Endothelial-derived microRNAs are involved in the modulation of these processes. Indeed, endothelial miR-16 is remarkably upregulated after vascular injury in the presences of hindlimb ischemia and exerts a negative effect on endothelial repair through the inhibition of RhoGDIα and nitric oxide (NO) production. We showed that the repression of RhoGDIα by means of miR-16 induces RhoA, with consequent reduction of NO bioavailability. Thus, hindlimb ischemia affects negative carotid remodeling increasing neointima formation after injury, while systemic antagonizzation of miR-16 is able to prevent these negative effects

Utilization of Healthcare Resources by Vascular Anomaly Patients: An Assessment of Healthcare Burden by Lesion Complexity

Background:. Vascular anomalies (VAs) are heterogeneous lesions. Symptoms vary widely by lesion type and complexity. VA patients often require life-long interdisciplinary care; however, there is a paucity of data on the healthcare utilization of VA patients, and their burden on the healthcare system remains largely unquantified. We hypothesize that healthcare utilization by complex lymphatic malformation (LM) and venous malformation (VM) patients will be significantly higher compared with simple LM and VM patients. Methods:. A retrospective, longitudinal study was performed of LM/VM patients seen through multidisciplinary VA clinics between January 1, 2019 and December 31, 2020. Data were collected from each patient’s first presentation through December 31, 2021 and included number of office visits, imaging studies, specialists involved, procedures, hospitalization data, and approximate costs, normalized to per year utilization. Patients were divided into “simple” and “complex” LMs/VMs. Involvement of the airway, more than one anatomic area, and/or complex lymphatic anomalies were defined as “complex.” Results:. In total, 28 simple and 29 complex LM patients and 51 simple and 18 complex VM patients were identified. Complex LM and VM patients had significantly higher numbers of imaging studies, specialists involved, procedures and hospitalizations, and costs incurred. Complex LM patients also had significantly higher per year office visits. Conclusions:. VA care is chronic and costly, especially for complex LM/VM patients. LM/VM complexity was a predictor for increased inpatient and outpatient healthcare utilization and higher costs. Better awareness of the healthcare utilization trends of LM/VM patients will allow for improved counseling for these patients regarding prognosis and expectations