11 research outputs found
Assessment of Methodological Pipelines for the Determination of Isothiocyanates Derived from Natural Sources
Isothiocyanates are biologically active secondary metabolites liberated via enzymatic hydrolysis of their sulfur enriched precursors, glucosinolates, upon tissue plant disruption. The importance of this class of compounds lies in their capacity to induce anti-cancer, anti-microbial, anti-inflammatory, neuroprotective, and other bioactive properties. As such, their isolation from natural sources is of utmost importance. In this review article, an extensive examination of the various parameters (hydrolysis, extraction, and quantification) affecting the isolation of isothiocyanates from naturally-derived sources is presented. Overall, the effective isolation/extraction and quantification of isothiocyanate is strongly associated with their chemical and physicochemical properties, such as polarity-solubility as well as thermal and acidic stability. Furthermore, the successful activation of myrosinase appears to be a major factor affecting the conversion of glucosinolates into active isothiocyanates. © 2022 by the authors. Licensee MDPI, Basel, Switzerland
Benzyl and phenethyl isothiocyanates as promising epigenetic drug compounds by modulating histone acetylation and methylation marks in malignant melanoma
Melanoma is an aggressive skin cancer with increasing incidence rates globally. On the other hand, isothiocyanates are derived from cruciferous vegetables and are known to exert a wide range of anti-cancer activities including, among others, their ability to interact with the epigenome in order to supress cancer progression. The aim of this study was to determine the role of phenethyl and benzyl isothiocyanates in modulating histone acetylation and methylation as a potential epigenetic therapeutic strategy in an in vitro model of malignant melanoma. We report that both isothiocyanates induced cytotoxicity and influenced acetylation and methylation status of specific lysine residues on histones H3 and H4 by modulating the expression of various histone acetyltransferases, deacetylases and methyltransferases in malignant melanoma cells. Our data highlight novel insights on the interaction of isothiocyanates with components of the histone regulatory machinery in order to exert their anti-cancer action in malignant melanoma. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature
Relationship between individual cardiovascular risk factors and localization of coronary atherosclerotic lesions
Objective: The localization of coronary atherosclerotic lesions in patients with coronary artery disease is important. We investigated the relationship between individual cardiovascular risk factors and lesion localization in the coronary arteries. Methods: We studied 200 consecutive patients with suspected or known coronary artery disease who were referred for coronary angiography because of chest pain. We assessed the following cardiovascular risk factors: male gender, hypercholesterolemia, smoking, arterial hypertension, positive family history, and diabetes. We evaluated atherosclerotic lesions creating a stenosis ≥ 50% in the 3 coronary arteries and lesions creating a stenosis ≥ 30% in the left main stem. Results: Of the 200 study patients, 155 (78%) showed at least 1 coronary artery lesion with a luminal stenosis ≥ 50%. With an increasing number of risk factors, there was a significant progressive increase of diseased arteries (P < .001). There was a differential association between individual risk factors and lesions in the 3 coronary arteries. Male gender, hypercholesterolemia, and diabetes were predictors of lesions in the left anterior descending artery (odds ratios 2.365, 2.510, and 1.998, respectively). Predictors of left circumflex artery lesions were male gender, smoking, and diabetes (odds ratios 2.581, 1.913, and 2.280, respectively), whereas the only independent predictor of right coronary artery lesions was male gender (odds ratio 2.995). Diabetes was also significantly associated with lesions in the diagonal branches of the left anterior descending artery and the marginal branches of the left circumflex artery. Conclusion: Individual cardiovascular risk factors are associated with the localization of atherosclerotic lesions in the coronary circulation. © 2011 Elsevier Inc
An evaluation of the anti-carcinogenic response of major isothiocyanates in non-metastatic and metastatic melanoma cells
Malignant melanoma is one of the most deadly types of solid cancers, a property mainly attributed to its highly aggressive metastatic form. On the other hand, different classes of isothiocy-anates, a class of phytochemicals, present in cruciferous vegetables have been characterized by con-siderable anti-cancer activity in both in vitro and in vivo experimental models. In the current study, we investigated the anti-cancer response of five isothiocyanates in an in vitro model of melanoma consisting of non-metastatic (A375, B16F-10) and metastatic (VMM1, Hs294T) malignant melanoma as well as non-melanoma epidermoid carcinoma (A431) and non-tumorigenic melanocyte-neigh-boring keratinocyte (HaCaT) cells. Our aim was to compare different endpoints of cytotoxicity (e.g., reactive oxygen species, intracellular glutathione content, cell cycle growth arrest, apoptosis and necrosis) descriptive of an anti-cancer response between non-metastatic and metastatic melanoma as well as non-melanoma epidermoid carcinoma and non-tumorigenic cells. Our results showed that exposure to isothiocyanates induced an increase in intracellular reactive oxygen species and glutathione contents between non-metastatic and metastatic melanoma cells. The distribution of cell cycle phases followed a similar pattern in a manner where non-metastatic and metastatic melanoma cells appeared to be growth arrested at the G2/M phase while elevated levels of metastatic melanoma cells were shown to be at sub G1 phase, an indicator of necrotic cell death. Finally, metastatic melanoma cells were more sensitive apoptosis and/or necrosis as higher levels were observed com-pared to non-melanoma epidermoid carcinoma and non-tumorigenic cells. In general, non-mela-noma epidermoid carcinoma and non-tumorigenic cells were more resistant under any experimental exposure condition. Overall, our study provides further evidence for the potential development of isothiocyanates as promising anti-cancer agents against non-metastatic and metastatic melanoma cells, a property specific for these cells and not shared by non-melanoma epidermoid carcinoma or non-tumorigenic melanocyte cells. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
Evaluation of Bioactive Properties of Lipophilic Fractions of Edible and Non-Edible Parts of Nasturtium officinale (Watercress) in a Model of Human Malignant Melanoma Cells
Watercress is an enriched source of phenethyl isothiocyanate (PEITC), among other phyto-chemicals, with an antioxidant capacity. The aim of this study was to (i) chemically characterize and (ii) biologically evaluate the profile of the main health-promoting compounds contained in edible (i.e., mixture of leaves and lateral buds) and non-edible (i.e., stems) parts of watercress in an in vitro model of malignant melanoma consisting of human malignant melanoma (A375), non-melanoma (A431) and keratinocyte (HaCaT) cells. The extraction of the main constituents of watercress was performed by subjecting the freeze-dried edible and non-edible samples through different extraction protocols, whereas their concentration was obtained utilizing analytical methodologies. In addition, cell viability was evaluated by the Alamar Blue assay, whereas levels of oxidative stress and apoptosis were determined by commercially available kits. The edible watercress sample contained a higher amount of various nutrients and phytochemicals in the hexane fraction compared to the non-edible one, as evidenced by the presence of PEITC, phenolics, flavonoids, pigments, ascorbic acid, etc. The cytotoxicity potential of the edible watercress sample in the hexane fraction was considerably higher than the non-edible one in A375 cells, whereas A431 and HaCaT cells appeared to be either more resistant or minimally affected, respectively. Finally, levels of oxidative stress and apoptotic induction were increased in both watercress samples, but the magnitude of the induction was much higher in the edible than the non-edible watercress samples. Herein, we provide further evidence document-ing the potential development of watercress extracts (including watercress waste by-products) as promising anti-cancer agent(s) against malignant melanoma cells. © 2022 by the authors. Licensee MDPI, Basel, Switzerland
A novel methylated analogue of L-Mimosine exerts its therapeutic potency through ROS production and ceramide-induced apoptosis in malignant melanoma
Melanoma is an aggressive and highly metastatic type of skin cancer where the design of new therapies is of utmost importance for the clinical management of the disease. Thus, we have aimed to investigate the mode of action by which a novel methylated analogue of L-Mimosine (e.g., L-SK-4) exerts its therapeutic potency in an in vitro model of malignant melanoma. Cytotoxicity was assessed by the Alamar Blue assay, oxidative stress by commercially available kits, ROS generation, caspase 3/7 activation and mitochondrial membrane depolarisation by flow cytometry, expression of apoptosis-related proteins by western immunoblotting and profiling of lipid biosynthesis by a metabolomic approach. Overall, higher levels of ROS, sphingolipids and apoptosis were induced by L-SK-4 suggesting that the compound’s therapeutic potency is mediated through elevated ROS levels which promote the upregulation of sphingolipid (ceramide) biosynthesis thus leading to the activation of both extrinsic and intrinsic apoptosis, in an experimental model of malignant melanoma. © 2021, The Author(s)
A New Standard DNA Damage (SDD) Data Format
Our understanding of radiation-induced cellular damage has greatly improved over the past few decades. Despite this progress, there are still many obstacles to fully understand how radiation interacts with biologically relevant cellular components, such as DNA, to cause observable end points such as cell killing. Damage in DNA is identified as a major route of cell killing. One hurdle when modeling biological effects is the difficulty in directly comparing results generated by members of different research groups. Multiple Monte Carlo codes have been developed to simulate damage induction at the DNA scale, while at the same time various groups have developed models that describe DNA repair processes with varying levels of detail. These repair models are intrinsically linked to the damage model employed in their development, making it difficult to disentangle systematic effects in either part of the modeling chain. These modeling chains typically consist of track-structure Monte Carlo simulations of the physical interactions creating direct damages to DNA, followed by simulations of the production and initial reactions of chemical species causing so-called “indirect” damages. After the induction of DNA damage, DNA repair models combine the simulated damage patterns with biological models to determine the biological consequences of the damage. To date, the effect of the environment, such as molecular oxygen (normoxic vs. hypoxic), has been poorly considered. We propose a new standard DNA damage (SDD) data format to unify the interface between the simulation of damage induction in DNA and the biological modeling of DNA repair processes, and introduce the effect of the environment (molecular oxygen or other compounds) as a flexible parameter. Such a standard greatly facilitates inter-model comparisons, providing an ideal environment to tease out model assumptions and identify persistent, underlying mechanisms. Through inter-model comparisons, this unified standard has the potential to greatly advance our understanding of the underlying mechanisms of radiation-induced DNA damage and the resulting observable biological effects when radiation parameters and/or environmental conditions change
Interaction of low energy protons, deuterons,
We have performed measurements of energy-angle distributions for low energy
(E ≲ 10 keV) hydrogen ions transmitted through thin amorphous carbon
foils. The applicability of standard potentials for the description of the multiple
scattering is tested by making comparisons of the experimental results with theoretical
calculations using the model of Sigmund and Winterbon on a broad angular scale. The
angular dependence of the energy loss for protons and deuterons is analyzed using the
three-components model of Famá et al., that separately considers the contribution of
elastic and inelastic mechanisms and the roughness effect. Additionally, the velocity
dependence of the stopping power and the possible existence of isotopic and molecular
effects in the energy loss is investigated by measurements with H+,
D+, \hbox{} and
\hbox{} beams of velocities
between 0.15 and 0.6 a.u