Background: Serum concentrations of ST2 (interleukin-1 receptor-like 1) represent a meaningful prognostic marker in cardiac diseases. Production of soluble ST2 (sST2) may be partially extracardiac. Identification of sST2 sources is relevant to design strategies for modulating its signaling. Methods and Results: An experimental model of ischemic heart failure was used. sST2, membrane-bound ST2 (ST2L), and IL-33 were measured in lungs, heart, kidney, and liver by quantifying mRNA and protein expression in tissue samples obtained at different times (1, 2, 4, and 24 weeks). Primary human type II pneumocyte cell cultures were subjected to strain. sST2 was measured in samples of bronchial aspirate and serum obtained from patients treated with invasive respiratory support. In the experimental model, sST2 increased significantly from the first week in both lungs and myocardium, whereas ST2L/IL-33 response was unfavorable in lungs (decrease) and favorable in myocardium (increase). No changes were observed in liver and kidneys. ST2 immunostaining was intensely observed in alveolar epithelium, and sST2 was secreted by primary human type II pneumocytes in response to strain. sST2 levels in lung aspirates were substantially higher in the presence of cardiogenic pulmonary edema (median, 228 [interquartile range, 28.4–324.0] ng/mL; P <0.001) than bronchopneumonia (median, 5.5 [interquartile range, 1.6–6.5]) or neurological disorders (median, 2.9 [interquartile range, 1.7–10.1]), whereas sST2 concentrations in serum did not differ. Conclusions: The lungs are a relevant source of sST2 in heart failure. These results may have implications for the progression of disease and the development of therapies targeting the ST2 system in patients with heart failure.

Admission sNEP concentration was associated with short- and long-term outcomes in AHF, and dynamic sNEP concentrations were observed during hospital admission. These preliminary data may be hypothesis-generating for the use of NEP inhibitors in AHF.

Background: Colchicine has been proposed as a potential therapy in coronavirus disease 2019 due to their anti-inflammatory actions. Methods: The COL-COVID study was a prospective, randomized, controlled and openlabel clinical trial that compared colchicine added to standard treatment vs standard treatment in hospitalized COVID-19 patients that do not need mechanical ventilatory support. Colchicine was initiated within the first 48 hours of admission at a 1.5 mg loading dose, followed by 0.5 mg b.i.d. for one week and 0.5 mg per day for 28 days. The study endpoints were clinical status (7-points WHO ordinal scale) and inflammatory biomarkers (IL-6 and CRP). Results: A total of 103 patients (51±12 years, 52% male) were randomly allocated to colchicine arm (n=52) and control arm (n=51). At day 28, all patients in the colchicine group were alive and discharged, whereas in the control group, two patients died in-hospital and one patient remained hospitalized. Clinical improvement in terms of changes on WHO scale at day 14 and 28 and time to 1-point clinical improvement did not differ between the two groups. Clinical deterioration (increase of at least 1-point in WHO scale) was observed in a higher proportion of cases in colchicine group (13.8%) vs control group (5.8%) (p=0.303); after adjustment by baseline risk factors and concomitant therapies, colchicine therapy was associated with a lower risk of clinical deterioration (p=0.030). Inflammatory biomarkers CRP and IL-6 concentrations course did not differ between the two arms. Conclusion:In hospitalized COVID-19 patients, colchicine treatment neither improved the clinical status, nor the inflammatory response, over the standard treatment. Nevertheless, a preventive effect for further clinical deterioration might be possible. Trial Registration: NCT04350320.