In this work, five novel phosphonium salts derived from the Michael reaction were screened for their antiplatelet activity. Our findings revealed that compounds 2a, 2b, 2c, and 2d significantly inhibit platelet aggregation triggered by ADP or collagen (P < 0.001). Notably, compound 2c inhibited the arachidonic acid pathway (P < 0.001). Moreover, the selected compounds reduce CD62-P expression and inhibit GPIIb/IIIa activation. The interactions of the active compounds with their targets, ADP and collagen receptors, P2Y12 and GPVI respectively were investigated in silico using molecular docking studies. The results revealed a strong affinity of the active compounds for P2Y12 and GPVI. Additionally, cytotoxicity assays on platelets, erythrocytes, and human embryonic kidney HEK293 cells showed that compounds 2a, 2c and 2d were non-toxic even at high concentrations. In summary, our study shows that phosphonium salts can have strong antiplatelet power and suggests that compounds 2a, 2c and 2d could be promising antiplatelet agents for the management of cardiovascular diseases.

Protein-rich polysaccharides are increasingly recognized as multifunctional biopolymers with significant biomedical potential. In this study, a protein–polysaccharide complex (JrPRP) was isolated for the first time from the root bark of Juglans regia L. and comprehensively characterized. JrPRP was obtained with a yield of 4.7% (w/w) and exhibited an acidic composition enriched in uronic acid-related components, together with minor neutral sugars. Spectroscopic analyses (FTIR and UV–Vis) confirmed the coexistence of carbohydrate and protein domains, while chromatographic profiling (TLC and HPLC) indicated a heterogeneous monosaccharide composition. Scanning electron microscopy revealed a porous and irregular microstructure, consistent with a structured biopolymeric network exhibiting pronounced anionic character. Functionally, JrPRP demonstrated notable antioxidant activity, with IC₅₀ values of 405 ± 1.8 µg/mL (DPPH), 225 ± 3.5 µg/mL (ABTS), and 229 ± 1.7 µg/mL (metal chelation), along with strong ferric-reducing capacity. The complex exhibited antibacterial activity against Pseudomonas aeruginosa, Klebsiella pneumoniae, and Staphylococcus aureus (MIC: 2–9 mg/mL), as well as potent antibiofilm activity, inhibiting up to 94% of Escherichia coli biofilm formation. Biocompatibility assays indicated low hemolytic activity, supporting its favorable safety profile. In addition, JrPRP showed moderate anticoagulant effects and strong anti-inflammatory activity, reaching 98% inhibition of protein denaturation, comparable to or exceeding diclofenac under similar conditions. These findings identify J. regia root bark as a promising and previously underexplored source of structurally distinctive uronic acid-containing protein-rich polysaccharides and provide new insights into the relationship between their compositional features and multifunctional biological activities.

Lauryl gallate (LG, E312) is an antioxidant with hydrophobic properties that contribute to its activity by increasing affinity for membranes and acting on the lipid phase transition and likely the lateral membrane organization. Here, we show that LG at a low concentration has the ability to spontaneously induce washed human platelet shape change, filopodia emission, granule secretion, and aggregation. LG was able to activate intracellular signaling pathways, including Akt, p38MAP kinase, inositol phosphate, and calcium responses, as well as to trigger cyclic adenosine monophosphate decrease and αIIbβ3 integrin activation. LG significantly potentiated platelet aggregation induced by low concentrations of agonists, and the addition of low doses of LG to human blood strongly increased the platelet thrombotic response under arterial flow on a collagen matrix. Morphological analysis by scanning electron microscopy indicated that contrary to low doses, high concentrations of LG induced dramatic platelet membrane modifications associated with calcium influx, lactate dehydrogenase leakage, and a slow platelet aggregation response. Interestingly, a local flash application of LG efficiently decreased the tail bleeding time in rats. LG action was rapid and significantly more efficient than tranexamic acid, an antifibrinolytic agent, pointing to its hemostatic potential. Overall, our results indicate that LG, likely through its capacity to modify membrane lateral organization, has important pro-aggregant and antihemorrhagic properties.

Glycosaminoglycans (GAGs) are the carbohydrate portion of proteoglycans (PGS), a family of complex biomacromolecules ubiquitously found in the extracellular matrix and on cell surfaces that play critical roles in a plethora of physiological and pathological processes. In the present work, chondroitin sulfate (CS) and dermatan sulfate (DS) were extracted and purified from the head (GCB) and skin (GDB) of blue runner fish (Caranx crysos) to explore their structural features and biological properties. GCB and GDB were purified by ion-exchange chromatography with yields of 0.82% and 0.61%, respectively. Chemical and structural analysis showed that GCB and GDD demonstrated quite similar sulfation degrees (4.45% and 4.24%, respectively). The molecular weight values obtained for GCB and GDB as estimated by high-performance size exclusion chromatography coupled with a triple detector array (HP-SEC-TDA) were 48.9 and 28.54 KDa, respectively. Structural features were elucidated using FT-IR and 2D NMR spectroscopy. GCB was mainly identified as chondroitin sulfate, containing 82% GlcA and minor proportions of IdoA and IdoA2S (scoring 18% dermatan-like structures). In contrast, GDB was predominantly dermatan sulfate, with a higher unsulfated IdoA content (54%) and a lower GlcA percentage (17%). In vitro anticoagulant activity, evaluated using APTT and PT assays, demonstrated that both GAGs exhibit significant anticoagulant potential. In addition, both fractions exhibited no antiplatelet activity, suggesting that the isolated glycosaminoglycans selectively target the coagulation cascade without affecting platelet aggregation. Furthermore, hemolytic assays confirmed that neither GCB nor GDB showed any hemolytic activity at the tested concentrations. Cytotoxicity assessment in HEK293 and HUVEK cell lines further confirmed the absence of detectable toxicity even at high concentration. Overall, these marine-derived GAGs present promising therapeutic potential as a source of anticoagulant drugs.