Effect of the Glucagon-Like Peptide-1 Receptor Agonists on Autonomic Function in Subjects with Diabetes: A Systematic Review and Meta-Analysis

Background: In addition to the metabolic effects in diabetes, glucagon-like peptide 1 receptor (GLP-1R) agonists lead to a small but substantial increase in heart rate (HR). However, the GLP-1R actions on the autonomic nervous system (ANS) in diabetes remain debated. Therefore, this meta-analysis evaluates the effect of GLP-1R agonist on measures of ANS function in diabetes. Methods: According to the Cochrane Collaboration and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, we conducted a meta-analysis considering clinical trials in which the autonomic function was evaluated in diabetic subjects chronically treated with GLP-1R agonists. The outcomes were the change of ANS function measured by heart rate variability (HRV) and cardiac autonomic reflex tests (CARTs). Results: In the studies enrolled, HR significantly increased after treatment (P<0.001), whereas low frequency/high frequency ratio did not differ (P=0.410); no changes in other measures of HRV were detected. Considering CARTs, only the 30:15 value derived from lying-to-standing test was significantly lower after treatment (P=0.002), but only two studies reported this measurement. No differences in other CARTs outcome were observed. Conclusion: The meta-analysis confirms the HR increase but seems to exclude an alteration of the sympatho-vagal balance due to chronic treatment with GLP-1R agonists in diabetes, considering the available measures of ANS function

Origin of Visible Light Photoactivity of the CeO2/ZnO Heterojunction

open6noThe synthesis of a mixed CeO2-ZnO oxide results in a photocatalyst active under visible light. The characterization of the new material shows that Ce does not enter as a dopant in ZnO but rather forms isolated CeO2 nanoparticles supported on the surface of larger particles of the more abundant zinc oxide phase. The as obtained material exhibits a band gap corresponding to UV light (similar to 3.3 eV), but nevertheless. it shows a relevant photoactivity under irradiation with photons with lambda > 420 nm (visible light). The working hypothesis is that visible light irradiation leads to a charge separation and stabilization of a fraction of the carriers connected with the formation of the CeO2/ZnO interface. This phenomenon has been investigated by means of several methods. A specific EPR-based approach allowed to monitor and quantify the charge separation following the formation of holes in the valence band (VB) of the two materials. More complex is detecting the nature of the excited electrons, as this involves the formation of EPR invisible Ce3+ ions by trapping the electrons into localized 4f states of Ce ions at the interface between the two oxides. DFT calculations provide a rational for some of the observed phenomena and a basis for the discussion of the band alignment of the two systems as a consequence of the formation of a heterojunction. The theoretical results show that indeed electrons can be excited at the interface from the VB of the two oxides into the Ce 4f states with photons of 2.3 eV, thus justifying the occurrence of a visible-light activity despite the higher band gap of the two materials.openCerrato, E.; Gionco, C.; Paganini, M.C.; Giamello, E.; Albanese, E.; Pacchioni, G.Cerrato, E.; Gionco, C.; Paganini, M. C.; Giamello, E.; Albanese, E.; Pacchioni, G

Paramagnetic defects in polycrystalline zirconia: An EPR and DFT study

The paramagnetic defects present in pristine zirconium dioxide (ZrO2) and those formed upon reductive treatments (either annealing or UV irradiation in H-2) are described and rationalized by the joint use of electron paramagnetic resonance (EPR) and DFT supercell calculations. Three types of Zr3+ reduced sites have been examined both in the bulk of the solid (one center) and at the surface (two centers). Trapping electron centers different from reduced Zr ions are also present, whose concentration increases upon annealing. A fraction of these sites are paramagnetic showing a symmetric signal at g = 2.0023, but the majority of them are EPR silent and are revealed by analysis of electron transfer from the reduced solid to oxygen. The presence of classic F-type centers (electrons in bulk oxygen vacancies) is disregarded on the basis of the g-tensor symmetry. This is expected, on the basis of theoretical calculations, to be anisotropic and thus incompatible with the observed signal. In general terms, ZrO2 has Some properties similar to typical reducible oxides, such as TiO2 and CeO2 (excess electrons stabilized at cationic sites), but it is much more resistant to reduction than this class of materials. While point defects in doped (Y3+, Ca2+) ZrO2 materials have been widely investigated for their role as ionic conductors, the defectivity of pristine ZrO2 is much less known; this paper presents a thorough analysis of this phenomenon

Single cell analysis reveals the involvement of the long non-coding RNA Pvt1 in the modulation of muscle atrophy and mitochondrial network

Long non-coding RNAs (lncRNAs) are emerging as important players in the regulation of several aspects of cellular biology. For a better comprehension of their function, it is fundamental to determine their tissue or cell specificity and to identify their subcellular localization. In fact, the activity of lncRNAs may vary according to cell and tissue specificity and subcellular compartmentalization. Myofibers are the smallest complete contractile system of skeletal muscle influencing its contraction velocity and metabolism. How lncRNAs are expressed in different myofibers, participate in metabolism regulation and muscle atrophy or how they are compartmentalized within a single myofiber is still unknown. We compiled a comprehensive catalog of lncRNAs expressed in skeletal muscle, associating the fiber-type specificity and subcellular location to each of them, and demonstrating that many lncRNAs can be involved in the biological processes de-regulated during muscle atrophy. We demonstrated that the lncRNA Pvt1, activated early during muscle atrophy, impacts mitochondrial respiration and morphology and affects mito/autophagy, apoptosis and myofiber size in vivo. This work corroborates the importance of lncRNAs in the regulation of metabolism and neuromuscular pathologies and offers a valuable resource to study the metabolism in single cells characterized by pronounced plasticity

Could chronic Vardenafil administration influence the cardiovascular risk in men with type 2 diabetes mellitus?

Introduction Appropriate algorithms for the prediction of cardiovascular risk are strongly suggested in clinical practice, although still controversial. In type 2 diabetes mellitus (T2DM), the benefi- cial effect of phosphodiesterase (PDE)-5 inhibitors is demonstrated on endothelial function but not on the estimation of cardiovascular risk. Aim To study whether the chronic Vardenafil administration to men with T2DM influences vari- ables correlated with the predicted long-term cardiovascular risk calculated by different vali- dated algorithms. Methods Per-protocol analysis of a longitudinal, prospective, randomized, placebo-controlled, dou- ble-blind, investigator-started, clinical trial. 54 male patients affected by T2DM were assigned to study (26patients) and control-group (28patients), respectively. The study included a treatment phase (24weeks) (Vardenafil/placebo 10mg twice-daily) and a follow- up phase (24weeks). Three time points were considered: baseline(V0), end of treatment (V1) and end of the study(V2). Parameters evaluated: endothelial health-related parameters and cardiovascular risk, assessed by calculating the Framingham (coronary hart disease [CHD], myocardial infarction [MI], stroke and cardiovascular disease [CVD]), ASSIGN and CUORE equations. Results Predicted cardiovascular risk at ten years resulted different using the three algorithms cho- sen, without differences between study and control groups and among visits. IL-6 was directly related to CHD, CVD and CUORE scores at V1 and with MI and STROKE at V2. Similarly, hs-CRP was directly related to CHD, MI, STROKE and CUORE only at V1 in the study group. Testosterone serum levels were inversely related to CHD and MI at V1 in study group. Discussion The predicted cardiovascular risk is different depending on the algorithm chosen. Despite no predictive risk reduction after six months of treatment, a possible effect of Vardenafil could be hypothesized through its action on inflammation markers reduction and through restoration of normal testosterone levels

Manifestazioni cliniche della neuropatia autonomica diabetica: valutazione dei sintomi.

La neuropatia autonomica diabetica (NAD) è una complicanza frequente del diabete, a insorgenza precoce e a forte impatto in termini di diagnosi, gestione di malattia e compromissione della qualità di vita dei soggetti affetti. Le manifestazioni cliniche della NAD sono numerose e possono interessare tutti gli organi e apparati; in questo contesto, la NAD cardiaca è la forma clinicamente più importante in quanto fattore di rischio per mortalità cardiovascolare. Il gold standard per la diagnosi di NAD cardiaca è rappresentato dai test cardiovascolari (cardiovascular autonomic reflex tests, CARTs), mentre la valutazione dei sintomi in passato era stata considerata di utilità diagnostica non rilevante date la bassa specificità dei sintomi e l’indisponibilità di questionari validati. Pertanto, la seguente rassegna prende in esame le novità in termini di valutazione e monitoraggio dei sintomi disautonomici nella NAD