Biology subjects

Hunyadi, A.

Publications and source records attributed to Hunyadi, A..

4 recordsLinked to original sources

bioRxiv2024

Green microwave-assisted extraction of Euphorbia guyoniana: Optimization, metabolite profile and in vivo anti-inflammatory potential

This study aimed to optimize microwave-assisted extraction of phenolic compounds from undervalued traditional plant Euphorbia guyoniana (Boiss. & Reut.) using central composite design of response surface methodology. The independent variables were extraction time (x1: 5 - 25 min), ethanol concentration in the extractive solvent (x2: 30 - 70%), microwave power (x3: 180 - 800 Watt) and feed-to-solvent ratio (x4: 1:7.5 - 1:17.5) while dependent variables were total phenolic content (TPC) and total flavonoid content (TFC). Extract obtained by using the optimal extraction parameters was evaluated for its in vivo anti-inflammatory activity by the carrageenan-induced paw edema model and was subjected to RP-HPLC-PDA-ESI-MS analysis to investigate the presence of phenolic compounds. The optimal conditions for highest TPC (377.22 {+/-} 5.42 mg GAE/100g) and TFC (184.40 {+/-} 1.18 mg QE/100g) were obtained at extraction time of 25 min, ethanol concentration of 40.57%, microwave power of 450 Watt and feed-to-solvent ratio of 1:17.5. The quadratic models significantly (p < 0.0001) fitted the experimental data with R2 values of 0.984 and 0.970 for TPC and TFC, respectively. Optimal extract of Euphorbia guyoniana significantly higher inhibited carrageenan induced inflammation with a concentration of 50 mg/kg (75,98%) when compared with reference anti-inflammatory drug ibuprofen (43,77%). Finally, above the previously reported phenolic constituents, i.e, quercetin and kaempferol derivatives, hydroxycinnamates have been identified for the first time in Euphorbia guyoniana plant extract.

plant biology↗

bioRxiv2023

Thymoquinone-Protoflavone Hybrid Molecules as Potential Antitumor Agents

We describe herein the synthesis of eight new ester-coupled hybrid compounds from thymoquinone and protoflavone building blocks, and their bioactivity testing against multiple cancer cell lines. Among the hybrids, compound 14 showed promising activities in all cell lines studied. The highest activities were recorded against breast cancer cell lines with higher selectivity to MDA-MB-231 as compared to MCF-7. Even though the hybrids were found to be completely hydrolysed in 24 h under cell culture conditions, compound 14 demonstrated a ca. three times stronger activity against U-87 glioblastoma cells than a 1:1 mixture of its fragments. Protoflavone-thymoquinone hybrids may therefore serve as potential new antitumor leads particularly against glioblastoma.

pharmacology and toxicology↗

bioRxiv2023

17-Oxime ethers of oxidized ecdysteroid derivatives modulate oxidative stress in human brain endothelial cells and dose-dependently might protect or damage the blood-brain barrier

20-Hydroxyecdysone and several of its oxidized derivatives exert cytoprotective effect in mammals including ans. Inspired by this bioactivity of ecdysteroids, in the current study it was our aim to prepare a set of sidechainmodified derivatives and to evaluate their potential to protect the blood-brain barrier (BBB) from oxidative stress. Six novel ecdysteroids, including an oxime and five oxime ethers, were obtained through regioselective synthesis from a sidechain-cleaved calonysterone derivative 2 and fully characterized by comprehensive NMR techniques revealing their complete 1H and 13C signal assignments. Surprisingly, several compounds sensitized hCMEC/D3 brain microvascular endothelial cells to tert-butyl hydroperoxide (tBHP)-induced oxidative damage as recorded by impedance measurements. Compound 8, containing a benzyloxime ether moiety in its sidechain, was the only one that exerted a protective effect in a higher, 10 M dose, while at lower (10 M - 1 M) doses it promoted tBHP-induced cellular damage. Based on our results, 17-oxime ethers of oxidized ecdysteroids modulate oxidative stress of the BBB in a way that may point towards unexpected toxicity. Further studies are needed to evaluate any possible risk connected to dietary ecdysteroid consumption and CNS pathologies in which BBB damage plays an important role.

pharmacology and toxicology↗

bioRxiv2021

Ecdysteroids as natural doping substances in the blood of insectivorous bats

Bats have deserved much scientific attention due to their biological-ecological properties and increasingly recognized epidemiological significance. Ecdysteroids are insect-molting hormones that (under experimental conditions) have stimulating and anabolic effects in mammals, including humans. Therefore, these biologically active compounds are currently under consideration by the World Anti-Doping Agency (WADA) to become doping-controlled substances. Previously we demonstrated that low to high concentrations of ecdysteroids appear in the blood of insectivorous passerine birds. Since passerine birds and echolocating bats share several adaptive mechanisms in connection with flying, and insectivorism is also among their common traits, we hypothesized that ecdysteroids might also be present in the blood of insectivorous bats. To test this hypothesis, blood samples of eight insectivorous bat species were collected and analyzed for the presence of ecdysteroids with highly sensitive targeted ultra-high-performance liquid chromatography coupled to high-resolution quadrupole-orbitrap mass spectrometry method (UHPLC-HRMS). The results supported our hypothesis, because nine ecdysteroids were detected in bat blood. The spectrum of these ecdysteroids was similar in those bat species which have their most preferred food items from the same insect order, supporting insects as the most likely source of these hormones. It was also shown that the spectrum of blood-borne ecdysteroids was broader in the autumn than in the summer, and higher concentrations of 20-hydroxyecdysone were measured in samples of large size bat species in comparison with small size ones. Based on the known physiologic effects of ecdysteroids, we postulate that these results might have implications on the metabolic rate and parasite burdens of insectivorous bats.

zoology↗