Triphenyltin (TPT) is known to cause endocrine disruption, reproductive toxicity and a decrease in testosterone production. It is involved in the production of reactive oxygen species. Propolis has ...been reported to be an important antioxidant. Therefore, the present study aimed to elucidate the possible protective effects of propolis in alleviating the toxicity of triphenyltin chloride (TPTCl) on reproductive performance, testosterone levels, lipid peroxidation and enzyme activities in seminal plasma of male New Zealand white rabbits. Animals were orally administered the doses of propolis, TPTCl and propolis plus TPTCl every day for 12weeks. Results showed that semen quality was deteriorated following treatment with TPTCl. Also, testosterone levels, body weight (BW), relative weights of testes (RWT) and epididymis (RWE) were decreased. Thiobarbituric acid-reactive substances and lactate dehydrogenase were increased, while glutathione S-transferase, transaminases and phosphatases were decreased in seminal plasma of rabbits treated with TPTCl compared to control. Propolis alone significantly increased testosterone levels, BW, RTW, REW, semen characteristics and seminal plasma enzymes, and decreased the levels of free radicals and lactate dehydrogenase. Furthermore, the presence of propolis with TPTCl alleviates its toxic effects. From the present study, it can be concluded propolis can be effective in the protection of TPTCl-induced reproductive toxicity.
This study was undertaken to evaluate the effectiveness of L-ascorbic acid (AA) in alleviating the toxicity of aflatoxin B
1
(AFB
1
) in male New-Zealand white rabbits. Five rabbits (6 months of age ...and mean body weight 3.12 kg) per group were assigned to 1 of 6 treatment groups: 0 mg AA and 0 mg AFB
1
/kg BW (control); 20 mg AA/kg BW; 15 μg AFB
1
/kg BW; 15 μg AFB
1
plus 20 mg AA/kg BW; 30 μg AFB
1
/kg BW; 30 μg AFB
1
plus 20 mg AA/kg BW. Rabbits were orally administered their respective doses every other day for 9 weeks, followed by a 9-week recovery period where all drugs were withdrawn. Evaluations were made for hemato-biochemical parameters and enzymatic activities. Results showed that AFB
1
significantly (p < 0.05) decreased hemoglobin (Hb), total erythrocytic count (TEC) and packed cell volume (PCV), in a dose-dependent manner, and these effects were continued during the recovery period. Ascorbic acid caused an increase in these parameters, and alleviated the negative effect of AFB
1
during the treatment period. Additionally, serum concentrations of total protein, albumin and glucose were significantly (P < 0.05) declined by treatment with the high dose of aflatoxin and these effects were continued during the recovery period. Ascorbic acid caused non-significant increases in these parameters and alleviated the harmful effect of AFB
1
. On the other hand, aflatoxin treatment caused significant increases (P < 0.05) in the activities of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (AlP) during the treatment period in a dose dependent manner, and this effect was continued during the recovery period, especially with the high dose. Also, treatment with the high dose of aflatoxin caused significant increases (P < 0.05) in cholesterol and total bilirubin. Ascorbic acid caused significant decreases in these parameters and alleviated the harmful effects of AFB
1
. Whereas, Total leukocyte count (TLC), urea and creatinine were not significantly affected by aflatoxin-treatment. Generally, it is interesting feature that the treatment with AA alone had no negative effects on most of the previous parameters. Also, the presence of AA could diminished the adverse effects of AFB
1
on most of hematological and biochemical values, and enzymatic activities in rabbits.
Holocarboxylasesynthetase (HCS) catalyzes the binding of the vitamin biotin to histonesH3 and H4, thereby creating rare histonebiotinylation marks in the epigenome. These marksco-localize with ...K9-methylated histone H3 (H3K9me), an abundant gene repression mark. The abundance of H3K9me marks in transcriptionally competent loci decreases when HCS is knocked down and when cells are depleted of biotin. Here we tested the hypothesis that the creation of H3K9me marks is at least partially explained by physical interactions between HCS and histone-lysine N-methyltransferases. Using a novel
in silico
protocol, we predicted that HCS-interacting proteins contain a GGGG(K/R)G(I/M)R motif. Thismotif, with minor variations, is present in the histone-lysine N-methyltransferase EHMT1. Physical interactions between HCS and the N-terminal, ankyrin, and SET domains in EHMT1 were confirmed using yeast-two-hybrid assays, limited proteolysis assays, and co-immunoprecipitation. The interactions were stronger between HCS and the N-terminus in EHMT1 compared with the ankyrin and SET domains, consistent with the localization of the HCS-binding motif in the EHMT1 N-terminus. HCS has the catalytic activity to biotinylate K161 within the binding motif in EHMT1. Mutation of K161 weakenedthe physical interaction between EHMT1 and HCS, but it is unknown whether this effect was caused by loss of biotinylation or loss of the motif. Importantly, HCS knockdown decreased the abundance of H3K9me marks in repeats, suggesting that HCS plays a role in creating histone methylation marks in these loci. We conclude that physical interactionsbetween HCS and EHMT1 mediate epigenomic synergies between biotinylation and methylation events.
ABSTRACT
Hexachlorocyclohexane (HCH) was among the most commonly used pesticides after the Second World War. The extensive use of this hydrocarbon for almost six decades has created a contamination ...problem on a global scale, and bioremediation methods are being extensively explored. The reported ability of some
Devosia
species to grow in the presence of appreciable amounts of hydrocarbons (2,000 mg/kg of contaminated soil) is attracting closer attention. Here, we report the
de novo
genome assembly of two hydrocarbon-tolerating
Devosia
isolates,
D. chinhatensis
strain IPL18
T
and
D. geojensis
strain BD-c194
T
, as a first step toward understanding the metabolic pathways involved in their environmental adaptation and tolerance toward hydrocarbons.
Covalent modifications of histones are a crucial component of epigenetic events that regulate chromatin structures and gene function. Evidence exists that distinct lysine residues in histones are ...modified by covalent attachment of the vitamin biotin, catalyzed by biotinidase and holocarboxylase synthetase. Biotinylation of histones appears to be conserved across species. The following biotinylation sites were identified using both MS and enzymatic biotinylation of synthetic peptides: K9, K13, K125, K127, and K129 in histone H2A; K4, K9, and K18 in histone H3; and K8 and K12 in histone H4. Evidence was provided that biotinylated histone H4 is enriched in pericentromeric heterochromatin, and that biotinylation of histone H4 participates in gene silencing, mitotic condensation of chromatin, and the cellular response to DNA damage. Biotinylation of histones is a reversible process and depends on the exogenous biotin supply, but the identities of histone debiotinylases remain uncertain. We propose that some effects of biotin deficiency can be attributed to abnormal chromatin structures.
Recent advances in “omics” research have resulted in the creation of large datasets that were generated by consortiums and centers, small datasets that were generated by individual investigators, and ...bioinformatics tools for mining these datasets. It is important for nutrition laboratories to take full advantage of the analysis tools to interrogate datasets for information relevant to genomics, epigenomics, transcriptomics, proteomics, and metabolomics. This review provides guidance regarding bioinformatics resources that are currently available in the public domain, with the intent to provide a starting point for investigators who want to take advantage of the opportunities provided by the bioinformatics field.
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