106 research outputs found
Use of FTA® classic cards for epigenetic analysis of sperm DNA
FTA® technologies provide the most reliable method for DNA extraction. Although FTA technologies have been widely used for genetic analysis, there is no literature on their use for epigenetic analysis yet. We present for the first time, a simple method for quantitative methylation assessment based on sperm cells stored on Whatman FTA classic cards. Specifically, elution of seminal DNA from FTA classic cards was successfully tested with an elution buffer and an incubation step in a thermocycler. The eluted DNA was bisulfite converted, amplified by PCR, and a region of interest was pyrosequenced
In Vitro Sprouted Plantlets of Citrullus colocynthis (L.) Schrad Shown to Possess Interesting Levels of Cucurbitacins and Other Bioactives against Pathogenic Fungi
Cucurbitacins, structurally different triterpenes mainly found in the members of Cucurbitaceae, possess a vast pharmacological potential. Genus Cucurbita, Cucumis, and Citrullus are affluent in these bioactive compounds, and, amongst them, Citrullus colocynthis (L.) Schrad. is widely exploited in folk medicine, since a huge number of diseases are successfully treated with organic and aqueous extracts obtained from different organs and tissues of the plant. The well-known pharmacological activities of such species have been attributed to its peculiar composition, which includes cucurbitacins and other bioactive molecules; thus, owing to its high importance as a valuable natural resource for pharmaceuticals and nutraceuticals, C. colocynthis propagation and multiplication protocols are considered significant, but the exploitation of its phytochemical potential is limited by the restricted cultivation conditions and the low rate of seed germination in the natural environment; in fact, the assessment of accumulation rate of specific phytochemicals under controlled conditions is still missing. Axenically sprouted plantlets obtained without the use of culture media or the addition of hormones have been evaluated here for the production of bioactive compounds and relevant bioactive features. Our results proved that derived organic extracts contain cucurbitacins and other bioactives, show antioxidant potential, and exert activity against some pathogenic fungi (Candida krusei, C. albicans, C. parapsilosis, C. glabrata, and Aspergillus flavus), supporting the feasibility of a methodology intended to scale-up cultivation of this species as a source of pharmaceutically interesting compounds, achievable from plantlets cultivated under laboratory conditions
Polymorphism rs7214723 in CAMKK1: a new genetic variant associated with cardiovascular diseases
Cardiovascular diseases (CVDs) are the leading cause of deaths worldwide. CVDs have a
complex etiology due to the several factors underlying its development including environment,
lifestyle, and genetics. Given the role of calcium signal transduction in several CVDs,
we investigated via PCR-restriction fragment length polymorphism (RFLP) the single nucleotide
polymorphism (SNP) rs7214723 within the calcium/calmodulin-dependent kinase
kinase 1 (CAMKK1) gene coding for the Ca2+/calmodulin-dependent protein kinase kinase
I. The variant rs7214723 causes E375G substitution within the kinase domain of CAMKK1.
A cross-sectional study was conducted on 300 cardiac patients. RFLP-PCR technique was
applied, and statistical analysis was performed to evaluate genotypic and allelic frequencies
and to identify an association between SNP and risk of developing specific CVD. Genotype
and allele frequencies for rs7214723 were statistically different between cardiopathic and
several European reference populations. A logistic regression analysis adjusted for gender,
age, diabetes, hypertension, BMI and previous history of malignancy was applied on cardiopathic
genotypic data and no association was found between rs7214723 polymorphism
and risk of developing specific coronary artery disease (CAD) and aortic stenosis (AS). These
results suggest the potential role of rs7214723 in CVD susceptibility as a possible genetic
biomarker
Heavy metals modulate DNA compaction and methylation at CpG sites in the metal hyperaccumulator Arabidopsis halleri
Excess heavy metals affect plant physiology by inducing stress symptoms, however several species have evolved the ability to hyperaccumulate metals in above-ground tissues without phytotoxic effects. In this study we assume that at subcellular level, different strategies were adopted by hyperaccumulator versus the non-accumulator plant species to face the excess of heavy metals. At this purpose the comet assay was used to investigate the nucleoid structure modifications occurring in response to Zn and Cd treatments in the I16 and PL22 populations of the hyperaccumulator Arabidopsis halleri versus the nonaccumulator species Arabidopsis thaliana. Methy-sens comet assay and RT-qPCR were also performed to associate metal induced variations in nucleoids with possible epigenetic modifications. The comet assay showed that Zn induced a mild but non significant reduction in the tail moment in A. thaliana and in both I16 and PL22. Cd treatment induced an increase in DNA migration in nuclei of A. thaliana, whereas no differences in DNA migration was observed for I16, and a significant increase in nucleoid condensation was found in PL22 Cd treated samples. This last population showed higher CpG DNA methylation upon Cd treatment than in control conditions, and an upregulation of genes involved in symmetric methylation and histone deacetylation. Our data support the hypothesis of a possible role of epigenetic modifications in the hyperaccumulation trait to cope with the high Cd shoot concentrations. In addition, the differences observed between PL22 and I16 could reinforce previous suggestions of divergent strategies for metals detoxification developing in the two metallicolous populations
DNA methylation is enhanced during Cd hyperaccumulation in Noccaea caerulescens ecotype Ganges
In this study, we assess the DNA damage occurring in response to cadmium (Cd) in the Cd hyperaccumulator Noccaea
caerulescens Ganges (GA) vs the non-accumulator and close-relative species Arabidopsis thaliana. At this purpose, the
alkaline comet assay was utilized to evaluate the Cd-induced variations in nucleoids and the methy-sens comet assay, and
semiquantitative real-time (qRT)-PCR were also performed to associate nucleus variations to possible DNA modifications.
Cadmium induced high DNA damages in nuclei of A. thaliana while only a small increase in DNA migration was observed in
N. caerulescens GA. In addition, in N. caerulescens GA, CpG DNA methylation increase upon Cd when compared to control
condition, along with an increase in the expression of MET1 gene, coding for the DNA-methyltransferase. N. caerulescens
GA does not show any oxidative stress under Cd treatment, while A. thaliana Cd-treated plants showed an upregulation of
transcripts of the respiratory burst oxidase, accumulation of reactive oxygen species, and enhanced superoxide dismutase
activity. These data suggest that epigenetic modifications occur in the N. caerulescens GA exposed to Cd to preserve genome
integrity, contributing to Cd tolerance
Investigation of antibacterial activity of new classes of essential oils derivatives
Essential oils (EOs) have deserved much attention in the past decades for their antimicrobial activity, since many of them have demonstrated efficacy against food-borne pathogenic and spoilage microorganisms. Moreover, they have potential application in animal nutrition as multifunctional feed supplements, avoiding or diminishing the use of antibiotics in livestock. However, low solubility and bioavailability as well as volatility and marked aromatic note are important limitations in food and feed applications. In this study we present the synthesis, characterization and evaluation of the antibacterial activity of new thymol, carvacrol and menthol derivatives. The new compounds have been designed to overcome the limitations of the precursors, such as poor water solubility and volatility, still maintaining a good antimicrobial profile. We evaluated the activity of the synthetized compounds against pathogens causing important foodborne diseases, . i.e. . Clostridium perfringens, . Salmonella typhimurium, . Salmonella enteritidis and . Escherichia coli. The low MICs and MBCs values for some of the studied compounds, combined with water solubility and negligible cytotoxicity towards HT-29 human cells, confirmed the potential use for EOs derivatives in the food industry
Genotoxicity Revaluation of Three Commercial Nitroheterocyclic Drugs: Nifurtimox, Benznidazole, and Metronidazole
Nitroheterocyclic compounds are widely used as therapeutic agents against a variety of protozoan and bacterial infections. However, the literature on these compounds, suspected of being carcinogens, is widely controversial. In this study, cytotoxic and genotoxic potential of three drugs, Nifurtimox (NFX), Benznidazole (BNZ), and Metronidazole (MTZ) was re-evaluated by different assays. Only NFX reduces survival rate in actively proliferating cells. The compounds are more active for base-pair substitution than frameshift induction in Salmonella; NFX and BNZ are more mutagenic than MTZ; they are widely dependent from nitroreduction whereas microsomal fraction S9 weakly affects the mutagenic potential. Comet assay detects BNZ- and NFX-induced DNA damage at doses in the range of therapeutically treated patient plasma concentration; BNZ seems to mainly act through ROS generation whereas a dose-dependent mechanism of DNA damaging is suggested for NFX. The lack of effects on mammalian cells for MTZ is confirmed also in MN assay whereas MN induction is observed for NFX and BNZ. The effects of MTZ, that shows comparatively low reduction potential, seem to be strictly dependent on anaerobic/hypoxic conditions. Both NFX and BNZ may not only lead to cellular damage of the infective agent but also interact with the DNA of mammalian cells
Cleaning the Label of Cured Meat; Effect of the Replacement of Nitrates/Nitrites on Nutrients Bioaccessibility, Peptides Formation, and Cellular Toxicity of In Vitro Digested Salami
Curing salts composed of mixtures of nitrates and nitrites are preservatives widely used in processed meats. Despite many desirable technological effects, their use in meat products has been linked to methemoglobinemia and the formation of nitrosamines. Therefore, an increasing "anti-nitrite feeling" has grown among meat consumers, who search for clean label products. In this view, the use of natural compounds as alternatives represents a challenge for the meat industry. Processing (including formulation and fermentation) induces chemical or physical changes of food matrix that can modify the bioaccessibility of nutrients and the formation of peptides, impacting on the real nutritional value of food. In this study we investigated the effect of nitrate/nitrite replacement with a combination of polyphenols, ascorbate, and nitrate-reducing microbial starter cultures on the bioaccessibility of fatty acids, the hydrolysis of proteins and the release of bioactive peptides after in vitro digestion. Moreover, digested salami formulations were investigated for their impacts on cell proliferation and genotoxicity in the human intestinal cellular model (HT-29 cell line). The results indicated that a replacement of synthetic nitrates/nitrites with natural additives can represent a promising strategy to develop innovative "clean label" salamis without negatively affecting their nutritional value
engineering methionine γ lyase from citrobacter freundii for anticancer activity
Abstract Methionine deprivation of cancer cells, which are deficient in methionine biosynthesis, has been envisioned as a therapeutic strategy to reduce cancer cell viability. Methionine γ-lyase (MGL), an enzyme that degrades methionine, has been exploited to selectively remove the amino acid from cancer cell environment. In order to increase MGL catalytic activity, we performed sequence and structure conservation analysis of MGLs from various microorganisms. Whereas most of the residues in the active site and at the dimer interface were found to be conserved, residues located in the C-terminal flexible loop, forming a wall of the active site entry channel, were found to be variable. Therefore, we carried out site-saturation mutagenesis at four independent positions of the C-terminal flexible loop, P357, V358, P360 and A366 of MGL from Citrobacter freundii, generating libraries that were screened for activity. Among the active variants, V358Y exhibits a 1.9-fold increase in the catalytic rate and a 3-fold increase in KM, resulting in a catalytic efficiency similar to wild type MGL. V358Y cytotoxic activity was assessed towards a panel of cancer and nonmalignant cell lines and found to exhibit IC50 lower than the wild type. The comparison of the 3D-structure of V358Y MGL with other MGL available structures indicates that the C-terminal loop is either in an open or closed conformation that does not depend on the amino acid at position 358. Nevertheless, mutations at this position allosterically affects catalysis
Ability of a high-total antioxidant capacity diet to increase stool weight and bowel antioxidant status in human subjects
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