Systematic Review of Endocan as a Potential Biomarker of COVID-19.

Since the start of the coronavirus disease 2019 (COVID-19) pandemic, several biomarkers have been proposed to assess the diagnosis and prognosis of this disease. The present systematic review evaluated endocan (a marker of endothelial cell damage) as a potential diagnostic and prognostic biomarker for COVID-19. PubMed, Scopus, Web of Science, and Embase were searched for studies comparing circulating endocan levels between COVID-19 cases and controls, and/or different severities/complications of COVID-19. Eight studies (686 individuals) were included, from which four reported significantly higher levels of endocan in COVID-19 cases compared with healthy controls. More severe disease was also associated with higher endocan levels in some of the studies. Studies reported higher endocan levels in patients who died from COVID-19, were admitted to an intensive care unit, and had COVID-19-related complications. Endocan also acted as a diagnostic and prognostic biomarker with different cut-offs. In conclusion, endocan could be a novel diagnostic and prognostic biomarker for COVID-19. Further studies with larger sample sizes are warranted to evaluate this role of endocan.

Triglyceride-glucose index and heart failure: a systematic review and meta-analysis.

BACKGROUND: Insulin resistance (IR) is a major metabolic disorder observed in heart failure (HF) and is tightly associated with patients' poor prognosis. The triglyceride-glucose index (TyG) has been proposed as a surrogate marker of IR in HF. Yet, whether TyG is a reliable clinical marker is still under debate. Hence, we aimed to respond to this relevant question via a systematic review and meta-analysis of existing studies. METHODS: A systematic search was conducted in PubMed, Embase, Scopus, and Web of Science to find studies investigating the TyG index in patients with HF or its association with the incidence of HF. Adjusted hazard ratios (HR) and 95% confidence intervals (CI) were pooled through random-effect meta-analysis. HRs were calculated using TyG as a continuous variable (1 unit increase) and by comparing the group with the highest TyG to the lowest TyG group. RESULTS: Thirty studies, involving 772,809 participants, were included in this systematic review. Meta-analysis of seven studies comparing the highest-TyG to the lowest-TyG group showed a significantly increased risk of HF in the former group (HR 1.21, 95% CI 1.14 to 1.29, P < 0.01). The same result was found when pooling the HRs for a one-unit increase in the TyG index (HR 1.17, 95% CI 1.08 to 1.26). Similarly, a more elevated TyG index was associated with a higher incidence of HF in patients with type 2 diabetes or coronary artery disease. Additionally, the incidence of adverse events (readmission and mortality) in patients with HF was associated with TyG. CONCLUSION: Our findings support the TyG index as a valuable marker to assess the risk of HF incidence in different populations and as a prognostic marker in patients with HF. Further studies should be conducted to confirm these associations and investigate the clinical utility of the TyG index.

Role of galectin-3 as a biomarker in obstructive sleep apnea: a systematic review and meta-analysis.

BACKGROUND: Because obstructive sleep apnea (OSA) is a prevalent condition, biomarkers for OSA would be very useful. Galectin-3 has gained attention as a marker for several diseases. The aim of this study was to investigate the association between circulating galectin-3 levels and OSA. METHODS: PubMed, Scopus, Embase, and Web of Science were explored to find the studies evaluating galectin-3 in OSA and controls, within different severities of OSA, or before and after continuous positive airway pressure (CPAP) treatment in cases with OSA. We used random-effect meta-analysis to calculate standardized mean differences (SMD) along with 95% confidence intervals (CI). Newcastle-Ottawa Scale was used assessment of the risk of bias in studies. RESULTS: An initial search resulted in 289 results. After exclusion of duplicate studies, screening of titles/abstracts and assessments of full texts, six studies were included comprised of 987 cases with a mean age of 54.4 years. Meta-analysis showed that there were significantly higher galectin-3 circulating levels in patients with OSA than in healthy controls (SMD 0.80, 95% CI 0.30 to 1.31, p value < 0.01). Severe OSA was related to higher levels of galectin-3, in comparison to non-severe OSA (SMD 0.76, 95% CI 0.29 to 1.22, p value < 0.01). CPAP therapy also significantly reduced galectin-3 peripheral levels in patients with OSA (SMD - 3.55, 95% CI - 6.90 to - 0.20, p value = 0.04). CONCLUSION: The findings suggest that Galectin-3 may have potential utility as a biomarker in patients with OSA. Further research is needed to demonstrate its role in pathophysiology, as well as its possible use in diagnosis and prognosis.

Angiotensin-converting enzyme 2 (ACE2) receptor and SARS-CoV-2: Potential therapeutic targeting.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a beta coronavirus that uses the human angiotensin-converting enzyme 2 (ACE2) receptor as a point of entry. The present review discusses the origin and structure of the virus and its mechanism of cell entry followed by the therapeutic potentials of strategies directed towards SARS-CoV2-ACE2 binding, the renin-angiotensin system, and the kinin-kallikrein system. SARS-CoV2-ACE2 binding-directed approaches mainly consist of targeting receptor binding domain, ACE2 blockers, soluble ACE2, and host protease inhibitors. In conclusion, blocking or manipulating the SARS-CoV2-ACE2 binding interface perhaps offers the best tactic against the virus that should be treated as a fundamental subject of future research.