Extracellular Matrix in Calcific Aortic Valve Disease: Architecture, Dynamic and Perspectives.

Calcific Aortic Valve Disease (CAVD) is the most common valvular heart disease in developed countries and in the ageing population. It is strongly correlated to median age, affecting up to 13% of the population over the age of 65. Pathophysiological analysis indicates CAVD as a result of an active and degenerative disease, starting with sclerosis and chronic inflammation and then leaflet calcification, which ultimately can account for aortic stenosis. Although CAVD has been firstly recognized as a passive event mostly resulting from a degenerative aging process, much evidences suggests that calcification arises from different active processes, involving both aortic valve-resident cells (valve endothelial cells, valve interstitial cells, mesenchymal stem cells, innate immunity cells) and circulating cells (circulating mesenchymal cells, immunity cells). Moreover, a role for the cell-derived "matrix vesicles" and extracellular matrix (ECM) components has also been recognized. The aim of this work is to review the cellular and molecular alterations occurring in aortic valve during CAVD pathogenesis, focusing on the role of ECM in the natural course of the disease.

Methods to Study Protein-Binding to Pseudogene Transcripts.

One of the most commonly described biological feature of processed pseudogenes is the ability to influence the expression of their parental coding genes. As evidenced in several studies, the high sequence similarity between these RNA pairs sets up a certain level of competition for posttranscriptional regulators, including, among others, RNA-binding proteins (RBPs). RBPs may affect, positively or negatively, the stability of bound mRNAs, so that, if an overexpressed pseudogene competes with its homologous coding gene, the downstream protein synthesis would change, with potential pathological consequences. Given these premises, a rigorous and comprehensive understanding of interactions between pseudogene-parental gene RNA pairs and RBPs could provide further insights into the biological bases of complex diseases, such as cancer, cardiovascular disease, and type 2 diabetes, identifying novel predictive and/or prognostic biomarkers.Herein, we detail easily adaptable protocols of plasmid-based molecular cloning and RNA-electrophoretic mobility shift assay (EMSA) used in our laboratory for determining the interaction between a cytoplasmatic stabilizing protein (αCP1) and the pseudogene-parental gene RNA pair HMGA1-p /HMGA1. We also offer a general overview of RNA immunoprecipitation procedures and present novel bioinformatic tools for predicting RBPs binding sites on pseudogene transcripts.

Mediterranean Diet Nutrients to Turn the Tide against Insulin Resistance and Related Diseases.

Insulin resistance (IR), defined as an attenuated biological response to circulating insulin, is a fundamental defect in obesity and type 2 diabetes (T2D), and is also linked to a wide spectrum of pathological conditions, such as non-alcoholic fatty liver disease (NAFLD), cognitive impairment, endothelial dysfunction, chronic kidney disease (CKD), polycystic ovary syndrome (PCOS), and some endocrine tumors, including breast cancer. In obesity, the unbalanced production of pro- and anti-inflammatory adipocytokines can lead to the development of IR and its related metabolic complications, which are potentially reversible through weight-loss programs. The Mediterranean diet (MedDiet), characterized by high consumption of extra-virgin olive oil (EVOO), nuts, red wine, vegetables and other polyphenol-rich elements, has proved to be associated with greater improvement of IR in obese individuals, when compared to other nutritional interventions. Also, recent studies in either experimental animal models or in humans, have shown encouraging results for insulin-sensitizing nutritional supplements derived from MedDiet food sources in the modulation of pathognomonic traits of certain IR-related conditions, including polyunsaturated fatty acids from olive oil and seeds, anthocyanins from purple vegetables and fruits, resveratrol from grapes, and the EVOO-derived, oleacein. Although the pharmacological properties and clinical uses of these functional nutrients are still under investigation, the molecular mechanism(s) underlying the metabolic benefits appear to be compound-specific and, in some cases, point to a role in gene expression through an involvement of the nuclear high-mobility group A1 (HMGA1) protein.

Long-Term Effectiveness of Liraglutide for Weight Management and Glycemic Control in Type 2 Diabetes.

Background: Liraglutide is the first glucagon-like peptide-1 receptor agonist (GLP-1 RA) based on the human GLP-1 sequence, with potential weight loss benefits, approved for the treatment of type 2 diabetes (T2D) mellitus. Herein, we aimed to assess the 5-year effectiveness of Liraglutide in the management of weight and glycometabolic control in a Southern Italian cohort of overweight/obese T2D patients, who were naïve to GLP-1 RAs. Patients and Methods: Forty overweight or obese patients treated with Liraglutide at doses up to 1.8 mg/day, in combination with one or more oral antidiabetic agents, were retrospectively assessed at baseline, during, and after 60 months of continuous therapy. Results: After 5 years of Liraglutide treatment, body weight decreased from 92.1 ± 20.5 kg to 87.3 ± 20.0 Kg (p < 0.001), with a mean reduction of 5.0 ± 7.0 Kg and a body mass index (BMI) decrement of -2.0 ± 3.1 Kg/m2. On Spearman's univariate analysis, change in body weight was correlated with female gender and baseline BMI. Hemoglobin A1c (HbA1c) decreased from 7.9 ± 0.9% at baseline to 7.0 ± 0.7% at the end of the study period (p < 0.001), followed by a significant reduction in fasting plasma glucose. No significant differences emerged in other biochemical parameters, despite a trend toward improvement in lipid profile. Notwithstanding encouraging effects on several markers of cardiovascular disease (CVD), increments in the 5- and 10-year risk for the first atherosclerotic cardiovascular event were documented, as four incident cases of myocardial infarction. Conclusions: Prolonging treatment with Liraglutide can lead to durable benefits in relation to weight and glycemic control, with a greater impact on women. These results extend and corroborate previous observations, suggesting that gender per se may modulate the response to Liraglutide. Despite favorable effects on some established CVD risks factors, the long-term role of Liraglutide in primary prevention of CVD in patients with T2D remains controversial.

Long-Term Effectiveness and Safety of SGLT-2 Inhibitors in an Italian Cohort of Patients with Type 2 Diabetes Mellitus.

BACKGROUND: SGLT-2 (sodium-glucose cotransporter-2) inhibitors are a novel class of oral hypoglycemic agents for the management of type 2 diabetes mellitus (T2DM). Herein, we aimed to assess the long-term effectiveness and safety of SGLT-2 inhibitors in a Southern Italy population of subjects affected by T2DM. PATIENTS AND METHODS: 408 diabetic patients treated with one of the three SGLT-2 inhibitors currently available in Italy (dapagliflozin, empagliflozin, and canagliflozin), either alone or in combination with other antidiabetic drugs, were retrospectively assessed at baseline, during, and after 18 months of continuous therapy. RESULTS: Treatment with SGLT-2 inhibitors resulted in a median decrease in HbA1c of 0.9%, with a percentage of decrement of 12 in relation to the baseline value, followed by a significant reduction (P < 0.001) in fasting plasma glucose. Variations in HbA1c occurred independently of the baseline clinical or biochemical characteristics. In addition, treatment with SGLT-2 inhibitors reduced body weight (P < 0.008) and decreased diastolic blood pressure (P = 0.004). With regard to safety outcomes, 66 patients out of 91 stopped SGLT-2 inhibitors during follow-up because of chronic or recurring genital infections, while the rest experienced other adverse events, such as urinary tract infections, polyuria, nausea, hypotension, dizziness, acute coronary event, worsening of glycemic control status, and rapid deterioration of renal function. CONCLUSION: In our patients' population, the glycometabolic effects of SGLT-2 inhibitors were durable and comparable to those observed in multicenter randomized controlled trials. This notwithstanding safety concerns must be raised regarding the frequent occurrence of genitourinary infections and the risk of a rapid decline of renal function in patients with evidence of volume depletion and/or receiving other medications which can adversely affect kidney function.

HMGA1 and MMP-11 Are Overexpressed in Human Non-melanoma Skin Cancer.

BACKGROUND/AIM: The High-Mobility Group A1 (HMGA1) protein has been implicated in human malignancies, playing an important role in cancer proliferation, angiogenesis and metastasis. Increased HMGA1 expression has been found in skin mouse tumors, whereas Hmga1-null mice were protected against skin carcinogenesis. Here, we examined the expression of HMGA1 in human skin tumors, squamous cell carcinoma and basal cell carcinoma. MATERIALS AND METHODS: Tumor and normal skin tissues from 15 affected patients were surgically excised, and mRNA and protein extraction was performed. mRNA and protein content for both HMGA1 and MMP-11, a proteinase enzyme that plays a role in tumor development and progression, was measured by real-time PCR and western blotting, respectively. Data were analyzed by the SPSS software. RESULTS: HMGA1 mRNA and protein expression patterns were higher in neoplastic skin lesions, compared to normal skin (p<0.001). Similar results were observed for MMP-11. CONCLUSION: Our data confirm previous observations in mice studies, and suggest that HMGA1 and MMP-11 may play a key role in the proliferation and progression of skin tumors in humans.

Transcriptional regulation of the HMGA1 gene by octamer-binding proteins Oct-1 and Oct-2.

The High-Mobility Group AT-Hook 1 (HMGA1) protein is an architectural transcription factor that binds to AT-rich sequences in the promoter region of DNA and functions as a specific cofactor for gene activation. Previously, we demonstrated that HMGA1 is a key regulator of the insulin receptor (INSR) gene and an important downstream target of the INSR signaling cascade. Moreover, from a pathogenic point of view, overexpression of HMGA1 has been associated with human cancer, whereas functional variants of the HMGA1 gene have been recently linked to type 2 diabetes mellitus and metabolic syndrome. However, despite of this biological and pathological relevance, the mechanisms that control HMGA1 gene expression remain unknown. In this study, to define the molecular mechanism(s) that regulate HMGA1 gene expression, the HMGA1 gene promoter was investigated by transient transfection of different cell lines, either before or after DNA and siRNA cotransfections. An octamer motif was identified as an important element of transcriptional regulation of this gene, the interaction of which with the octamer transcription factors Oct-1 and Oct-2 is crucial in modulating HMGA1 gene and protein expression. Additionally, we demonstrate that HMGA1 binds its own promoter and contributes to its transactivation by Oct-2 (but not Oct-1), supporting its role in an auto-regulatory circuit. Overall, our results provide insight into the transcriptional regulation of the HMGA1 gene, revealing a differential control exerted by both Oct-1 and Oct-2. Furthermore, they consistently support the hypothesis that a putative defect in Oct-1 and/or Oct-2, by affecting HMGA1 expression, may cause INSR dysfunction, leading to defects of the INSR signaling pathway.