Universidade Federal do Rio Grande

In vivo and in vitro experiments were conducted to test whether copper (Cu) uptake occurs via sodium (Na⁺) transporters in the gills of Callinectes sapidus acclimated to dilute seawater (2 ppt), a condition in which the species hyper-osmoregulates. Specific inhibitors targeting Na⁺/H⁺ exchangers (amiloride, 100 μM) and Na⁺, K⁺, 2 Cl^- cotransporters (NKCC) (furosemide, 120 μM) were used. In vivo, adult crabs were exposed for 6 h to 1 μM radiolabeled Cu (⁶⁴Cu) in artificial seawater or Na-free media, both at 2 ppt. In vitro, isolated posterior gills were perfused with hemolymph-like saline and exposed to external solutions containing ⁶⁴Cu. Na⁺ uptake was first validated using radiolabeled Na (²⁴Na) and the inhibitors: in vivo Na⁺ uptake was significantly reduced by amiloride (68 %) and furosemide (23 %) and in vitro amiloride reduced Na⁺ uptake by 40 %. Cu uptake, however, remained unaffected by the Na⁺ presence/absence or by the inhibitors in both experimental approaches. The ⁶⁴Cu accumulated mainly in the carapace (49 %) and posterior gills (22 %), regardless of Na⁺ availability. The findings clearly demonstrate that Cu uptake, irrespective of the uptake pathway, proceeds independently of Na.

Resveratrol (RV), a natural polyphenol, has been extensively studied for its neuroprotective potential in Parkinson's Disease (PD), but its clinical translation is limited by poor bioavailability and rapid metabolism. Glycosylated derivatives, including polydatin and resveratrol-3-α-glucoside, have been proposed to improve the solubility and stability. This study compared the pharmacokinetic properties of RV and its derivatives and examined their molecular interactions with PD-related targets. ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) analysis showed that, despite improved solubility, RV retained a more favorable overall pharmacokinetic profile. Target prediction combined with Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and protein-protein interaction (PPI) network construction identified 50 potential targets, with 11 prioritized for molecular docking. Glycosylated derivatives exhibited binding affinities for all targets stronger than those of RV, with TNF-α, PPARγ, and ERBB2 highlighted as key candidates. These findings indicate that RV glycosylation may enhance therapeutic potential for PD treatment by promoting stronger molecular interactions with critical targets, though in vivo validation remains necessary.

The search for the genetic basis of phenotypes has primarily focused on single nucleotide polymorphisms, often overlooking structural variants (SVs). SVs can significantly affect gene function, but detecting and characterizing them is challenging, even with long-read sequencing. Moreover, traditional single-reference methods can fail to capture many genetic variants. Using long reads, we generated a Capuchino Seedeater (Sporophila) pangenome, including 16 individuals from 7 species, to investigate how SVs contribute to species and coloration differences. Leveraging this pangenome, we mapped short-read data from 127 individuals, genotyped variants identified in the pangenome graph, and subsequently performed FST scans and genome-wide association studies. Species divergence primarily arises from SNPs and indels (< 50 bp) in non-coding regions of melanin-related genes, as larger SVs rarely overlap with divergence peaks. One exception was a 55 bp deletion near the OCA2 and HERC2 genes, associated with feather pheomelanin content. These findings support the hypothesis that the reshuffling of small regulatory alleles, rather than larger species-specific mutations, accelerated plumage evolution leading to prezygotic isolation in Capuchinos.