Marina Deljanin Ilić

Background: Metabolic syndrome (MetSy) is characterized by the presence of obesity, hypertension, altered glucose metabolism, and/or increased non-HDL cholesterol. This study aimed at elucidating the association between obesity with subclinical target organ damage and biochemical parameters included in MetSy pathogenesis. Methods: This study included 130 apparently healthy subjects. Plasma levels of oxidized-LDL-cholesterol (ox-LDL-Chol), nitric oxide (NO) metabolites, inducible NO synthase (iNOS), and plasminogen activator inhibitor-1 (PAI-1) were measured. Non-invasive assessment of liver disease included fatty liver index (FLI) and nonalcoholic fatty liver disease (NAFLD) fibrosis score. Carotid artery plaques were assessed by color Doppler imaging. Results: A total of 65 patients with MetSy were included in the MetSy group, while 65 without MetSy entered the control group. Ox-LDL-Chol levels were higher in the MetSy group compared to the control group, regardless of obesity. Levels of NO metabolites were similar in obese and non-obese patients with MetSy, but lower than in the control group. Obese patients with MetSy had higher iNOS values compared to non-obese ones, with similar PAI-1 levels. NAFLD was present in all obese patients with MetSy compared to 70% of non-obese subjects. Hypertension, higher values of waist-to-hip ratio, PAI-1, and remnant cholesterol were associated with NAFLD. Finding of asymptomatic carotid plaques was associated with patients’ age, hypertension, and higher waist-to-hip ratio. Conclusion: MetSy and obesity significantly alter the levels of NO metabolites, iNOS, ox-LDL-Chol, and PAI-1. High prevalence of NAFLD in obese patients with MetSy requires active screening and treatment of potential risk factors.

Long-term exposure to amiodarone, an antiarrhythmic drug, can induce different organ damage, including liver. Cell damage included by amiodarone is a consequence of mitochondrial damage, reactive oxygen species production, and cell energy depletion leading to programmed cell death. In the present study, hepatoprotective potential of neurohormone melatonin (50 mg/kg/day) was evaluated in a chronic experimental model of liver damage induced by a 4-week application of amiodarone (70 mg/kg/day). The obtained results indicate that amiodarone induces an increase in xanthine oxidase activity, as well as the content of the lipid and protein oxidatively modified products and p53 levels. Microscopic analysis further corroborated the biochemical findings revealing hepatocyte degeneration, apoptosis, and occasional necrosis, with the activation of Kupffer cells. Coadministration of melatonin and amiodaron prevented an increase in certain damage associated parameters, due to its multiple targets. In conclusion, the application of melatonin together with amiodarone prevented an increase in tissue oxidative damage parameters and moderately prevented liver cell apoptosis, indicating that the damage of hepatocytes provoked by amiodarone supersedes the protective properties of melatonin in a given dose.

Background Diagnosis of heart failure with preserved ejection fraction (HFpEF) remains challenging despite the use of scores/algorithms. This study intended to assess the diagnostic value of exercise lung ultrasound (LUS) for HFpEF diagnosis. Methods We studied two independent case–control studies of HFpEF patients and control subjects undergoing different exercise protocols: (i) submaximal exercise stress echocardiography (ESE) with LUS performed by expert cardiologists (N = 116, HFpEF = 65.5%), and (ii) maximal cycle ergometer test (CET) (N = 54, HFpEF = 50%) with LUS performed by unexperienced physicians shortly trained for the study. B-line kinetics (i.e. peak values and their changes from rest) were assessed. Results In the ESE cohort, the C-index (95% CI) of peak B-lines for HFpEF diagnosis was 0.985 (0.968–1.000), whereas the C-index of rest and exercise HFA-PEFF scores (i.e. including stress echo findings) were < 0.90 (CI 0.823–0.949), and that of H2FPEF score was < 0.70 (CI 0.558–0.764). The C-index increase of peak B-lines on top of the above-mentioned scores was significant (C-index increase > 0.090 and P-value < 0.001 for all). Similar results were observed for change B-lines. Peak B-lines > 5 (sensitivity = 93.4%, specificity = 97.5%) and change B-lines > 3 (sensitivity = 94.7%, specificity = 87.5%) were the best cutoffs for HFpEF diagnosis. Adding peak or change B-lines on top of HFpEF scores and BNP significantly improved diagnostic accuracy. Peak B-lines showed a good diagnostic accuracy in the LUS beginner-led CET cohort (C-index = 0.713, 0.588–0.838). Conclusions Exercise LUS showed excellent diagnostic value for HFpEF diagnosis regardless of different exercise protocols/level of expertise, with additive diagnostic accuracy on top of available scores and natriuretic peptides. Graphical abstract