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Organ-Dependent Antioxidant, Redox-Modulating, and Lifespan Effects of Galanthus elwesii Extracts in Drosophila melanogaster.

Ertan O et al. · Jun 25, 2026

Galanthus elwesii is a pharmaceutically valuable Amaryllidaceae species known for its diverse bioactive metabolites; however, the relationship between its phytochemical profile, antioxidant capacity, and in vivo biological effects remains poorly understood. In this study, aerial (APE) and belowground (BPE) parts were extracted using water, methanol, and ethanol, and evaluated through a combined in vitro and in vivo approach. Total phenolic and flavonoid contents were quantified, and antioxidant activities were assessed via DPPH radical-scavenging and Fe 2+ metal-chelation assays, including IC 50 determination. The in vivo effects of selected extracts were investigated in Drosophila melanogaster through larval toxicity and developmental survival assays, adult lifespan analysis, and oxidative stress biomarkers (TAS, TOS, and OSI). Phytochemical composition and antioxidant activity exhibited strong organ- and solvent-dependent variability, with belowground extracts generally demonstrating higher phenolic content and stronger radical-scavenging and metal-chelating capacities. In vivo, most extracts showed low-to-moderate developmental toxicity at selected concentrations, while certain belowground extracts significantly extended lifespan at subtoxic doses. Oxidative status measurements revealed reduced TOS and OSI levels alongside maintained or increased TAS, indicating effective suppression of oxidative stress rather than direct antioxidant action. Correlation analysis revealed moderate negative correlations between phenolic/flavonoid content and antioxidant activity, although these relationships did not reach statistical significance. Overall, these findings suggest that G. elwesii extracts exert organ-dependent phytochemical and bioactivity profiles and may act as in vivo redox modulators associated with improvements in oxidative balance and lifespan-related parameters.

Chemistry

Proteomics risk scores and mortality in heart failure: Generalizability across populations.

Shearer JJ et al. · Jun 23, 2026

Background Heart failure (HF) is a complex syndrome with high mortality. Proteomics risk scores have shown promise in predicting mortality beyond guideline-recommended clinical tools. It is crucial to understand how risk scores generated by different methods and populations perform, and whether they highlight the same protein targets relevant to outcomes. Methods To examine whether the study design impacts proteomics scores designed to predict mortality in HF, we evaluated three published risk scores that used the SomaScan assay to measure plasma proteins in a community cohort, clinical trial, and registry. Each score was assessed in the aforementioned community cohort and Cox models examined the association of a 1-standard deviation increase in score with mortality, with and without adjustment for clinical covariates. Performance of each risk score to predict 5-year mortality risk was assessed using calibration plots and time-dependent area under the curve and compared with a clinical model. Results Risk scores were similarly distributed and moderately correlated (Pearson correlation coefficient = 0.59-0.76). A 1-standard deviation increase in each risk score was associated with an increased risk of all-cause mortality: community cohort (HR = 2.70, 95% CI: 2.50-2.91); clinical trial (HR = 1.76, 95% CI: 1.65-1.88); registry (HR = 1.70, 95% CI: 1.6-1.81). Risk remained after adjustment for clinical covariates, although slightly attenuated, and similar across different ejection fraction categories. All risk scores showed strong calibration across the risk levels, alone, with an average expected over observed ratio ranging between 0.96-1.56. Seven proteins were included in at least two risk scores, with renin being included in all three. Conclusions All three proteomics risk scores improved risk stratification in HF patients beyond guideline recommended clinical tools, independent of study design and ejection fraction. These results demonstrate that proteomics risk scores can enhance risk stratification across the HF syndrome, even when derived from different methods and populations.

Chemistry