In this study, we characterize the impact of antioxidative enzymes in amphotericin B (AmB)-resistant (ATR) and rare AmB-susceptible (ATS) clinical Aspergillus terreus isolates. We elucidate expression profiles of superoxide dismutase (SOD)- and catalase (CAT)-encoding genes, enzymatic activities of SODs, and superoxide anion production and signaling pathways involved in the oxidative stress response (OSR) in ATS and ATR strains under AmB treatment conditions. We show that ATR strains possess almost doubled basal SOD activity compared to that of ATS strains and that ATR strains exhibit an enhanced OSR, with significantly higher sod2 mRNA levels and significantly increased cat transcripts in ATR strains upon AmB treatment. In particular, inhibition of SOD and CAT proteins renders resistant isolates considerably susceptible to the drug in vitro . In conclusion, this study shows that SODs and CATs are crucial for AmB resistance in A. terreus and that targeting the OSR might offer new treatment perspectives for resistant species.

The disease trajectory of diabetic kidney disease (DKD) shows a high interindividual variability not sufficiently explained by conventional risk factors. Clonal hematopoiesis of indeterminate potential (CHIP) is a proposed novel cardiovascular risk factor. Increased kidney fibrosis and glomerulosclerosis were described in mouse models of CHIP. Here, we aim to analyze whether CHIP affects the incidence or progression of DKD. A total of 1419 eligible participants of the PROVALID Study were the basis for a nested case-control (NCC) design. A total of 64 participants who reached a prespecified composite endpoint within the observation period (initiation of kidney replacement therapy, death from kidney failure, sustained 40% decline in estimated glomerular filtration rate or sustained progression to macroalbuminuria) were identified and matched to 4 controls resulting in an NCC sample of 294 individuals. CHIP was assessed via targeted amplicon sequencing of 46 genes in peripheral blood. Furthermore, inflammatory cytokines were analyzed in plasma via a multiplex assay. The estimated prevalence of CHIP was 28.91% (95% CI 22.91%–34.91%). In contrast to other known risk factors (albuminuria, hemoglobin A1c, heart failure, and smoking) and elevated microinflammation, CHIP was not associated with incident or progressive DKD (hazard ratio [HR] 1.06 [95% CI 0.57–1.96]). In this NCC study, common risk factors as well as elevated microinflammation but not CHIP were associated with kidney function decline in type 2 diabetes mellitus.

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Cutaneous melanoma (CM) incidence is rising worldwide and is the primary cause of death from skin disease in the Western world. Personal risk factors linked to environmental ultraviolet radiation (UVR) are well-known etiological factors contributing to its development. Nevertheless, UVR can contribute to the development of CM in different patterns and to varying degrees. The present study aimed at investigating whether altitude of residence can contribute to the development of specific types of CM and/or influence its progression. To this aim, 306 formalin-fixed and paraffin-embedded (FFPE) tissues from primary CM diagnosed in different geographical areas were submitted to B-RAF proto-oncogene serine/threonine kinase (BRAF) and N-RAS proto-oncogene GTPase (NRAS) mutational status detection and mRNA and miRNA profiling by qPCR. Genes were chosen for their functions in specific processes, such as immune response (CD2, PDL1, or CD274) and pigmentation (MITF, TYRP1, and TRPM1). Furthermore, four microRNAs, namely miR-150-5p, miR-155-5p, miR-204-5p, and miR-211-5p, were included in the profiling. Our results highlight differences in the gene expression profile of primary CM with respect to the geographical area and the altitude of residence. Melanoma-specific survival was influenced by the gene expression of mRNA and miRNAs and varied with the altitude of patients’ residence. In detail, TYRP1 and miR-204-5p were highly expressed in patients living at higher altitudes, unlike miR-150-5p, miR-155-5p, and miR-211-5p. Since miRNAs are highly regulated by reactive oxygen species, it is possible that different regulatory mechanisms characterize CMs at different altitudes due to the different environment and UVR intensity.

Morphological heterogeneity of Aspergillus terreus cultures was observed during continued cultivation of amphotericin B (AMB)-resistant isolates on drug-free medium. Outgrowth leads to the emergence of multiple sectors that might result from increased growth rates at drug-free conditions. We evaluated the differences in AMB susceptibility and virulence between sector subcultures (ATSec), AMB-resistant (ATR) strains, and AMB-susceptible (ATS) strains. By comparing A. terreus AMB-resistant (ATR) strains and A. terreus sector (ATSec) cultures we observed a highly significant reduction of AMB MICs in ATSec (ATR MIC, 2 to 32 μg/ml; ATSec MIC, 0.12 to 5 μg/ml). Furthermore, Galleria mellonella survival studies revealed an enhanced virulence of ATSec, which was comparable with that of AMB-sensitive Aspergillus terreus strains (median survival rates for ATS isolates, 72 h; for ATSec isolate ATSec ^G1 , 84 h; for ATR isolates, 144 h). Our findings clearly demonstrate that spontaneous culture degeneration occurs in A. terreus and, most importantly, crucially impacts drug efficacy and virulence.