Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 26
Filter
1.
Int J Mol Sci ; 25(1)2023 Dec 29.
Article in English | MEDLINE | ID: mdl-38203648

ABSTRACT

Tert-butylhydroquinone (TBHQ) is a synthetic food antioxidant with biological activities, but little is known about its pharmacological benefits in liver disease. Therefore, this work aimed to evaluate TBHQ during acute liver damage induced by CCl4 (24 h) or BDL (48 h) in Wistar rats. It was found that pretreatment with TBHQ prevents 50% of mortality induced by a lethal dose of CCl4 (4 g/kg, i.p.), and 80% of BDL+TBHQ rats survived, while only 50% of the BDL group survived. Serum markers of liver damage and macroscopic and microscopic (H&E staining) observations suggest that TBHQ protects from both hepatocellular necrosis caused by the sublethal dose of CCl4 (1.6 g/kg, i.p.), as well as necrosis/ductal proliferation caused by BDL. Additionally, online databases identified 49 potential protein targets for TBHQ. Finally, a biological target candidate (Keap1) was evaluated in a proof-of-concept in silico molecular docking assay, resulting in an interaction energy of -5.5491 kcal/mol, which was higher than RA839 and lower than monoethyl fumarate (compounds known to bind to Keap1). These findings suggest that TBHQ increases the survival of animals subjected to CCl4 intoxication or BDL, presumably by reducing hepatocellular damage, probably due to the interaction of TBHQ with Keap1.


Subject(s)
Hydroquinones , NF-E2-Related Factor 2 , Animals , Rats , Rats, Wistar , Kelch-Like ECH-Associated Protein 1 , Molecular Docking Simulation , Necrosis
2.
Exp Appl Acarol ; 91(3): 487-496, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37787902

ABSTRACT

The effect of ethyl-4-bromophenyl carbamate on different Rhipicephalus microplus stages implanted in cattle was evaluated using the pen test with infestation chambers. Twelve steers were distributed into four groups (n = 3), each with four chambers (12 chambers per group), where approximately 1,000 R. microplus larvae were placed in each chamber. The chambers of the first group were sprayed with a solution of ethyl-4-bromophenyl carbamate (0.668 mg/mL) on day 2 post-infestation (PI) (exposed larvae). The chambers of the second group were sprayed with the same solution on day 8 PI (exposed nymphs), and the chambers of the third group were sprayed on day 16 PI (exposed adults) with the same solution. The chambers of the fourth group were used as controls. The percentages of engorged females, egg laying, egg production and egg hatching were evaluated in all groups. The percentage of cumulative reduction of hatched larvae was 98.3, 96.1 and 94.4% when larvae, nymph and adult stages were treated, respectively. The average cumulative reduction of hatched larvae, considering the three treated stages, was 96.3%, whereby the reproductive potential of this tick was drastically reduced. In conclusion, ethyl-4-bromophenyl carbamate acted as an ixodicide (lethal effect) when larval stages were sprayed and as a growth regulator when nymphal and adult stages were sprayed. The sum of these effects had a direct impact on the efficacy of the product in the pen test, and future studies will indicate the potential use of this product for tick control.


Subject(s)
Acaricides , Cattle Diseases , Rhipicephalus , Tick Infestations , Female , Cattle , Animals , Carbamates/pharmacology , Larva , Oviposition , Cattle Diseases/prevention & control , Nymph , Tick Infestations/prevention & control , Tick Infestations/veterinary , Acaricides/pharmacology
3.
Ecotoxicol Environ Saf ; 176: 219-225, 2019 Jul 30.
Article in English | MEDLINE | ID: mdl-30933896

ABSTRACT

The toxicity of the ixodicidal carbamates ethyl-4-bromophenyl carbamate (LQM 919), ethyl-4-chlorophenyl carbamate (LQM 996) and propoxur on Eisenia foetida adults was evaluated to estimate their ecotoxic potential. The earthworm mortality and weight loss produced by the three evaluated carbamates showed a concentration-dependent effect (p < 0.0001) in the contact filter paper test (CFPT). In the artificial soil test (AST), mortality increased in relation to the exposure time (p < 0.0001) and the concentration (p < 0.01) of the carbamates. Only the earthworms exposed in the CFPT showed morphological alterations. According to the LC50 obtained in the CFPT, the three carbamates were classified as very toxic and, according to the LC50 obtained in the AST, the three carbamates were classified as highly toxic for E. foetida. The values of ki and kd indicated that LQM 919 and LQM 996 are weak inhibitors with lower affinity for the acetylcholinesterase of E. foetida than that of propoxur. The concentrations in the CFPT and AST at which 100% mortality was observed in E. foetida were 64- and 4-fold higher, respectively, than the egg hatching inhibitory concentration 99% reported for ticks.


Subject(s)
Acetylcholinesterase/metabolism , Carbamates/toxicity , Oligochaeta/drug effects , Propoxur/toxicity , Soil Pollutants/toxicity , Animals , Lethal Dose 50 , Oligochaeta/enzymology , Soil/chemistry
4.
Breed Sci ; 66(3): 425-33, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27436953

ABSTRACT

Rice bran oil is a byproduct of the milling of rice (Oryza sativa L.). It offers various health benefits and has a beneficial fatty acid composition. To increase the amount of rice bran as a sink for triacylglycerol (TAG), we developed and characterized new breeding materials with giant embryos. To induce mutants, we treated fertilized egg cells of the high-yielding cultivar 'Mizuhochikara' with N-methyl-N-nitrosourea (MNU). By screening M2 seeds, we isolated four giant embryo mutant lines. Genetic analysis revealed that the causative loci in lines MGE12 and MGE13 were allelic to giant embryo (ge) on chromosome 7, and had base changes in the causal gene Os07g0603700. On the other hand, the causative loci in lines MGE8 and MGE14 were not allelic to ge, and both were newly mapped on chromosome 3. The TAG contents of all four mutant lines increased relative to their wild type, 'Mizuhochikara'. MGE13 was agronomically similar to 'Mizuhochikara' and would be useful for breeding for improved oil content.

5.
Anticancer Drugs ; 24(4): 394-405, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23388162

ABSTRACT

We present a study of the chemoprotective effects of two caffeic acid phenethyl ester (CAPE)-related structures: LQM717 and LQM706. The modified resistant hepatocyte model in rats was used to study the chemoprevention of these CAPE analogues, which are inexpensive and easily obtained. In the liver cancer model used, we detected extensive necrosis and lipid peroxidation after 24 h, many altered hepatic foci, putatively preneoplastic lesions with γ-glutamyl transpeptidase staining after 30 days, and liver tumors at 12 months. We tested the effect of the CAPE analogues on necrosis, lipid peroxidation, proliferation, p65 activation, altered hepatic foci, and tumors. Both compounds exerted protective effects on lipid peroxidation, necrosis, cell proliferation, p65 activation, and preneoplastic lesions. Rats under a carcinogenic protocol showed a 52, 71.74, and 51.6% decrease in the number of preneoplastic nodules when pretreated with CAPE, LQM706, and LQM717, respectively. At 12 months after carcinogenic treatment, eight of eight rats developed liver cancer, whereas in the group of rats that received pretreatment with CAPE, LQM706, or LQM717, 62.5, 83.3, or 42.85%, respectively, had tumors. In conclusion, LQM717 has the potential to enhance chemoprotection activity much better than CAPE by markedly reducing the formation of liver cancers in this model, and this is a compound that is easy to obtain.


Subject(s)
Acetanilides/pharmacology , Anticarcinogenic Agents/therapeutic use , Antioxidants/therapeutic use , Caffeic Acids/therapeutic use , Cinnamates/therapeutic use , Hepatocytes/drug effects , Liver Neoplasms, Experimental/drug therapy , Phenylethyl Alcohol/analogs & derivatives , Precancerous Conditions/drug therapy , 2-Acetylaminofluorene , Acetanilides/chemical synthesis , Acetanilides/therapeutic use , Animals , Anticarcinogenic Agents/chemical synthesis , Anticarcinogenic Agents/pharmacology , Antioxidants/chemical synthesis , Antioxidants/pharmacology , Caffeic Acids/pharmacology , Carcinogens , Cell Division/drug effects , Cinnamates/chemical synthesis , Cinnamates/pharmacology , Diethylnitrosamine , Drug Evaluation, Preclinical , Drug Resistance , Glutathione S-Transferase pi/analysis , Hepatectomy/adverse effects , Hepatocytes/chemistry , Hepatocytes/pathology , Ki-67 Antigen/analysis , Lipid Peroxidation/drug effects , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms, Experimental/pathology , Male , Molecular Structure , Phenylethyl Alcohol/pharmacology , Phenylethyl Alcohol/therapeutic use , Precancerous Conditions/chemically induced , Precancerous Conditions/pathology , Rats , Rats, Inbred F344 , Transcription Factor RelA/antagonists & inhibitors , Transcription Factor RelA/metabolism
6.
Front Microbiol ; 14: 1089156, 2023.
Article in English | MEDLINE | ID: mdl-36778890

ABSTRACT

The use of immunomodulatory and metabolic modulating drugs has been considered a better strategy to improve the efficacy of conventional treatments against pathogens and metabolic diseases. L-carnitine is relevant in fatty acid metabolism and energy production by ß-oxidation, but it also has a beneficial therapeutic immunomodulatory effect. The ß-hydroxy-γ-aminophosphonate (ß-HPC) was developed, synthesized and studied in different pathologies as a more soluble and stable analog than L-carnitine, which has been studied in bacterial physiology and metabolism; therefore, we set out to investigate the direct effect of ß-HPC on the metabolism of N. brasiliensis, which causes actinomycetoma in Mexico and is underdiagnosed. To analyze the effect of ß-HPC on the metabolic capacity of the bacterium for the hydrolysis of substrate casein, L-tyrosine, egg yolk, and tween 80, Fourier transform infrared spectroscopy (FT-IR) was employed. It was found that ß-HPC increases the metabolic activity of N. brasiliensis associated with increased growth and increased hydrolysis of the substrates tested. By the effect of ß-HPC, it was observed that, in the hydrolysis of L-tyrosine, the aromatic ring and functional groups were degraded. At 1515 cm-1, any distinctive signal or peak for this amino acid was missing, almost disappearing at 839, 720, 647, and 550 cm-1. In casein, hydrolysis is enhanced in the substrate, which is evident by the presence of NH, OH, amide, and CO. In casein, hydrolysis is enhanced in the substrate, which is evident by the presence of NH, OH, amide, COO, and P = O signals, characteristic of amino acids, in addition to the increase of the amide I and II bands. In Tween 80 the H-C = and C = C signals disappear and the ether signals are concentrated, it was distinguished by the intense band at 1100 cm-1. Egg yolk showed a large accumulation of phosphate groups at 1071 cm-1, where phosvitin is located. FT-IR has served to demonstrate that ß-HPC is a hydrolysis enhancer. Furthermore, by obtaining the spectrum of N. brasiliensis, we intend to use it as a quick comparison tool with other spectra related to actinobacteria. Eventually, FT-IR may serve as a species identification option.

7.
Pathogens ; 10(9)2021 Sep 17.
Article in English | MEDLINE | ID: mdl-34578240

ABSTRACT

At the end of 2019, the world was struck by the COVID-19 pandemic, which resulted in dire repercussions of unimaginable proportions. From the beginning, the international scientific community employed several strategies to tackle the spread of this disease. Most notably, these consisted of the development of a COVID-19 vaccine and the discovery of antiviral agents through the repositioning of already known drugs with methods such as de novo design. Previously, methylthiomorphic compounds, designed by our group as antihypertensive agents, have been shown to display an affinity with the ACE2 (angiotensin converting enzyme) receptor, a key mechanism required for SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) entry into target cells. Therefore, the objective of this work consists of evaluating, in silico, the inhibitory activity of these compounds between the ACE2 receptor and the S1 subunit of the SARS-CoV-2 spike protein. Supported by the advances of different research groups on the structure of the coronavirus spike and the interaction of the latter with its receptor, ACE2, we carried out a computational study that examined the effect of in-house designed compounds on the inhibition of said interaction. Our results indicate that the polyphenol LQM322 is one of the candidates that should be considered as a possible anti-COVID-19 agent.

8.
Mol Plant Microbe Interact ; 23(1): 29-38, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19958136

ABSTRACT

Rice tungro disease (RTD) is a serious constraint to rice production in South and Southeast Asia. RTD is caused by Rice tungro spherical virus (RTSV) and Rice tungro bacilliform virus. Rice cv. Utri Merah is resistant to RTSV. To identify the gene or genes involved in RTSV resistance, the association of genotypic and phenotypic variations for RTSV resistance was examined in backcross populations derived from Utri Merah and rice germplasm with known RTSV resistance. Genetic analysis revealed that resistance to RTSV in Utri Merah was controlled by a single recessive gene (tsv1) mapped within an approximately 200-kb region between 22.05 and 22.25 Mb of chromosome 7. A gene for putative translation initiation factor 4G (eIF4G(tsv1)) was found in the tsv1 region. Comparison of eIF4G(tsv1) gene sequences among susceptible and resistant plants suggested the association of RTSV resistance with one of the single nucleotide polymorphism (SNP) sites found in exon 9 of the gene. Examination of the SNP site in the eIF4G(tsv1) gene among various rice plants resistant and susceptible to RTSV corroborated the association of SNP or deletions in codons for Val(1060-1061) of the predicted eIF4G(tsv1) with RTSV resistance in rice.


Subject(s)
Eukaryotic Initiation Factor-4G/genetics , Eukaryotic Initiation Factor-4G/metabolism , Oryza , Polymorphism, Single Nucleotide/genetics , Waikavirus/physiology , Amino Acid Sequence , Chromosomes, Plant/genetics , Genes, Plant/genetics , Genes, Recessive/genetics , Immunity, Innate/genetics , Oryza/genetics , Oryza/virology , Plant Diseases/genetics , Plant Diseases/virology , Sequence Alignment
9.
Biomed Res Int ; 2020: 2981681, 2020.
Article in English | MEDLINE | ID: mdl-33274201

ABSTRACT

Ethyl-4-bromophenyl-carbamate (LQM 919) and Ethyl-4-chlorophenyl-carbamate (LQM 996) are compounds that inhibit egg-laying and hatching of tick larvae that are resistant to conventional ixodicides. The structure-activity relationship (SAR) to get the endpoint predictions of mutagenicity and carcinogenicity of the LQM 919 and LQM 996 was performed and the absence of mutagenicity was confirmed by Ames test. SAR analysis show no structural alerts indicating the ability of ethyl-carbamates to bind biomolecules or estrogen receptors. Endpoint of mutagenicity with and without metabolic activation showed that the ethyl-carbamates were negative (p <0.05) for mutagenicity induction in strains TA97, TA98, TA102, TA1535, TA1537 and TA1538 of Salmonella typhimurium. Pre-incubation with different ethyl-carbamate concentrations did not increase the number of spontaneously reverting colonies; moreover, the compounds did not induce a concentration-dependent increase in the number of reverting colonies in any of the strains used. This confirmed the absence of mutagenic activity in this test system. Exogenous metabolic activation did not modify these observations; suggesting that no metabolites with mutagenic activity were present. The endpoint of carcinogenicity in rats were negative for LQM 919 (p <0.05,) and LQM 996 (p <0.001). The results of the present study strongly suggest that ethyl-carbamates do not represent a risk for cancer in mammals.


Subject(s)
Carcinogens/chemistry , Carcinogens/toxicity , Ixodidae/drug effects , Mutagens/chemistry , Mutagens/toxicity , Urethane/chemistry , Urethane/toxicity , Animals , Salmonella typhimurium/drug effects , Structure-Activity Relationship
10.
Chemosphere ; 242: 125293, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31896202

ABSTRACT

The effects produced by the ethyl-carbamates: ethyl-4-bromophenyl carbamate (LQM 919) and ethyl-4-chlorophenyl carbamate (LQM 996) on the mortality and behavior of Apis mellifera were evaluated by the acute oral toxicity test and the acute contact toxicity test. The oral lethal dose, 50% of the ethyl-carbamates was >145.24 µg per bee, and the oral lethal dose, 50% of propoxur was 0.072 µg per bee. Therefore, according to the OECD criteria, the ethyl-carbamates were classified as relatively nontoxic orally; meanwhile, propoxur was classified as highly toxic orally. In the contact test, lethal concentrations 50% of the ethyl-carbamates were 4.83 and 2.23 µg/cm2 for LQM 919 and LQM 996, respectively; therefore, they were at least 10-fold less lethal (p < 0.05) than propoxur (0.22 µg/cm2). The ethyl-carbamates reduced the activity of A. mellifera acetylcholinesterase by up to 30%. The ki and kd values of both ethyl-carbamates were lower (p < 0.05) than those of propoxur and indicated that they are weak inhibitors and with low affinity to A. mellifera acetylcholinesterase, which along with the absence of behavioral alterations suggests that the mortality caused by ethyl carbamates is not related to damage to the nervous system. According to these results, the evaluated ethyl-carbamates can be considered a low ecotoxic risk for A. mellifera.


Subject(s)
Acetylcholinesterase/metabolism , Bees/drug effects , Carbamates/toxicity , Environmental Pollutants/toxicity , Insecticides/toxicity , Animals , Bees/enzymology , Behavior, Animal/drug effects , Dietary Exposure/adverse effects , Environmental Exposure/adverse effects , Lethal Dose 50 , Toxicity Tests, Acute
11.
Ticks Tick Borne Dis ; 11(2): 101326, 2020 03.
Article in English | MEDLINE | ID: mdl-31780375

ABSTRACT

The purpose of this work was to contribute to the understanding of the mechanism of action of two new ixodicides. The histological and ultrastructural alterations of Rhipicephalus microplus oocytes (San Alfonso strain) treated with two new ethyl-carbamates (ethyl-4-bromophenyl carbamate and ethyl-4-chlorophenyl carbamate) by the adult immersion test were evaluated by light microscopy and transmission electron microscopy. The effects of the carbamates on embryogenesis in eggs were evaluated by fluorescence microscopy using DAPI staining. Both ethyl-carbamates inhibited the maturation of most oocytes and induced a concentration-dependent decrease (r2  = 0.5, p < 0.05) in the embryonation percentage in the small number of eggs oviposited by treated ticks. Evident ultrastructural alterations were observed in the oocytes from ticks exposed to the ethyl-carbamates, including modification of the chorion structure, myelinic bodies and autophagic vacuoles that were associated with degenerated organelles (mitochondria, endoplasmic reticulum and yolk granules), nucleolus fragmentation and chromatin clumping in germinal vesicles. In conclusion, these ethyl-carbamates affect the reproductive potential of R. microplus due to their negative effects on oogenesis and their repercussions for embryonic development.


Subject(s)
Acaricides , Carbamates , Rhipicephalus , Tick Control , Animals , Embryo, Nonmammalian/drug effects , Embryonic Development/drug effects , Microscopy , Microscopy, Electron, Transmission , Microscopy, Fluorescence , Oocytes , Oogenesis/drug effects , Ovum/drug effects , Rhipicephalus/embryology , Rhipicephalus/growth & development
12.
J Phys Chem B ; 113(34): 11765-74, 2009 Aug 27.
Article in English | MEDLINE | ID: mdl-19653668

ABSTRACT

Four new antihypertensive piperidinylmethylphenol compounds were synthesized for their potential antihypertensive and antiarhythmic properties. The pKa values were determined experimentally, with the aid of the program SQUAD, by capillary zone electrophoresis (CZE) at T=298.15 K and 0.015 M ionic strength (I=0.05 M) and by UV spectrophotometry at pseudophysiological conditions (T=310.15 K and I=0.15 M), obtaining good agreement between the values determined with both techniques. A theoretical study was followed in order to propose a deprotonation mechanism for each compound.


Subject(s)
Antihypertensive Agents/chemistry , Computer Simulation , Models, Chemical , Phenols/chemistry , Piperidines/chemistry , Antihypertensive Agents/chemical synthesis , Electrophoresis, Capillary , Hydrogen-Ion Concentration , Osmolar Concentration , Phenols/chemical synthesis , Piperidines/chemical synthesis , Protons , Spectrophotometry, Ultraviolet
13.
Cell Rep ; 20(4): 881-894, 2017 07 25.
Article in English | MEDLINE | ID: mdl-28746873

ABSTRACT

Anucleate platelets circulate in the blood to facilitate thrombosis and diverse immune functions. Platelet activation leading to clot formation correlates with increased glycogenolysis, glucose uptake, glucose oxidation, and lactic acid production. Simultaneous deletion of glucose transporter (GLUT) 1 and GLUT3 (double knockout [DKO]) specifically in platelets completely abolished glucose uptake. In DKO platelets, mitochondrial oxidative metabolism of non-glycolytic substrates, such as glutamate, increased. Thrombosis and platelet activation were decreased through impairment at multiple activation nodes, including Ca2+ signaling, degranulation, and integrin activation. DKO mice developed thrombocytopenia, secondary to impaired pro-platelet formation from megakaryocytes, and increased platelet clearance resulting from cytosolic calcium overload and calpain activation. Systemic treatment with oligomycin, inhibiting mitochondrial metabolism, induced rapid clearance of platelets, with circulating counts dropping to zero in DKO mice, but not wild-type mice, demonstrating an essential role for energy metabolism in platelet viability. Thus, substrate metabolism is essential for platelet production, activation, and survival.


Subject(s)
Glucose Transporter Type 1/metabolism , Glucose Transporter Type 3/metabolism , Glucose/metabolism , Megakaryocytes/metabolism , Models, Theoretical , Animals , Blood Platelets/metabolism , Calcium/metabolism , Calpain/metabolism , Glucose Transporter Type 1/genetics , Glucose Transporter Type 3/genetics , Mice , Mice, Knockout , Necrosis/metabolism , Platelet Activation/genetics , Platelet Activation/physiology
14.
Article in English | MEDLINE | ID: mdl-27542710

ABSTRACT

The mammalian erythrocyte micronucleus test was used on the peripheral blood of Wistar rats exposed to two new ethyl-carbamates: ethyl-4-bromophenyl-carbamate (LQM 919) and ethyl-4-chlorophenyl-carbamate (LQM 996) to analyze their genotoxic potential. The mitotic index and cell proliferation kinetics in human lymphocyte cultures in the presence of these ethyl-carbamates were used to evaluate cytotoxicity and cytostaticity respectively. Exposure to greater acute doses (300mg/kg) and to all of the subchronic doses (12.5, 25 and 50mg/kg daily for 90 days) of these ethyl-carbamates induced an increased frequency (p<0.05) of micro-nucleated polychromatic erythrocytes (MN-PCE) compared with rats not exposed to the ethyl-carbamates. Increases in MN-PCE was higher in males than in females exposed to LQM 996 50mg/Kg (p<0.05). All observed changes in rats return 21days after suspending ethyl-carbamate exposure. The highest concentration (0.3mM) of both ethyl-carbamates in lymphocyte cultures increased the percentage of cells in first division metaphase and decreased the percentage of cells in third division metaphase, indicating an increase in cell cycle length or a possible cell cycle arrest in metaphase (cytostatic effect). The results of this study show that the evaluated ethyl-carbamates may induce genotoxic damage in rats and alterations in the human lymphocyte cell cycle.


Subject(s)
Acaricides/toxicity , Carbamates/toxicity , Cytostatic Agents/toxicity , Mutagens/toxicity , Urethane/toxicity , Acaricides/chemical synthesis , Animals , Carbamates/chemical synthesis , Cells, Cultured , Cytostatic Agents/chemical synthesis , Erythrocytes/drug effects , Female , Humans , Lymphocytes/drug effects , Male , Micronuclei, Chromosome-Defective , Mutagens/chemical synthesis , Rats , Rats, Wistar , Urethane/chemical synthesis
15.
Mol Cancer ; 4(1): 22, 2005 Jul 07.
Article in English | MEDLINE | ID: mdl-16001982

ABSTRACT

BACKGROUND: The development of cancer has been associated with epigenetic alterations such as aberrant histone deacetylase (HDAC) activity. It was recently reported that valproic acid is an effective inhibitor of histone deacetylases and as such induces tumor cell differentiation, apoptosis, or growth arrest. METHODS: Twelve newly diagnosed patients with cervical cancer were treated with magnesium valproate after a baseline tumor biopsy and blood sampling at the following dose levels (four patients each): 20 mg/kg; 30 mg/kg, or 40 mg/kg for 5 days via oral route. At day 6, tumor and blood sampling were repeated and the study protocol ended. Tumor acetylation of H3 and H4 histones and HDAC activity were evaluated by Western blot and colorimetric HDAC assay respectively. Blood levels of valproic acid were determined at day 6 once the steady-state was reached. Toxicity of treatment was evaluated at the end of study period. RESULTS: All patients completed the study medication. Mean daily dose for all patients was 1,890 mg. Corresponding means for the doses 20-, 30-, and 40-mg/kg were 1245, 2000, and 2425 mg, respectively. Depressed level of consciousness grade 2 was registered in nine patients. Ten patients were evaluated for H3 and H4 acetylation and HDAC activity. After treatment, we observed hyperacetylation of H3 and H4 in the tumors of nine and seven patients, respectively, whereas six patients demonstrated hyperacetylation of both histones. Serum levels of valproic acid ranged from 73.6-170.49 microg/mL. Tumor deacetylase activity decreased in eight patients (80%), whereas two had either no change or a mild increase. There was a statistically significant difference between pre and post-treatment values of HDAC activity (mean, 0.36 vs. 0.21, two-tailed t test p < 0.0264). There was no correlation between H3 and H4 tumor hyperacetylation with serum levels of valproic acid. CONCLUSION: Magnesium valproate at a dose between 20 and 40 mg/kg inhibits deacetylase activity and hyperacetylates histones in tumor tissues.


Subject(s)
Histone Deacetylases/metabolism , Histones/metabolism , Leukocytes/metabolism , Uterine Cervical Neoplasms/drug therapy , Uterine Cervical Neoplasms/metabolism , Valproic Acid/blood , Valproic Acid/therapeutic use , Acetylation , Adult , Aged , Dose-Response Relationship, Drug , Female , Humans , Middle Aged , Neoplasm Staging , Uterine Cervical Neoplasms/blood , Uterine Cervical Neoplasms/pathology , Valproic Acid/adverse effects , Valproic Acid/pharmacokinetics
16.
BMC Cancer ; 5: 44, 2005 Apr 29.
Article in English | MEDLINE | ID: mdl-15862127

ABSTRACT

BACKGROUND: The antihypertensive compound hydralazine is a known demethylating agent. This phase I study evaluated the tolerability and its effects upon DNA methylation and gene reactivation in patients with untreated cervical cancer. METHODS: Hydralazine was administered to cohorts of 4 patients at the following dose levels: I) 50 mg/day, II) 75 mg/day, III) 100 mg/day and IV) 150 mg/day. Tumor biopsies and peripheral blood samples were taken the day before and after treatment. The genes APC, MGMT; ER, GSTP1, DAPK, RARbeta, FHIT and p16 were evaluated pre and post-treatment for DNA promoter methylation and gene expression by MSP (Methylation-Specific PCR) and RT-PCR respectively in each of the tumor samples. Methylation of the imprinted H19 gene and the "normally methylated" sequence clone 1.2 was also analyzed. Global DNA methylation was analyzed by capillary electrophoresis and cytosine extension assay. Toxicity was evaluated using the NCI Common Toxicity Criteria. RESULTS: Hydralazine was well tolerated. Toxicities were mild being the most common nausea, dizziness, fatigue, headache and palpitations. Overall, 70% of the pretreatment samples and all the patients had at least one methylated gene. Rates of demethylation at the different dose levels were as follows: 50 mg/day, 40%; 75 mg/day, 52%, 100 mg/day, 43%, and 150 mg/day, 32%. Gene expression analysis showed only 12 informative cases, of these 9 (75%) re-expressed the gene. There was neither change in the methylation status of H19 and clone 1.2 nor changes in global DNA methylation. CONCLUSION: Hydralazine at doses between 50 and 150 mg/day is well tolerated and effective to demethylate and reactivate the expression of tumor suppressor genes without affecting global DNA methylation.


Subject(s)
Cardiovascular Diseases/drug therapy , DNA Methylation/drug effects , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Hydralazine/pharmacology , Uterine Cervical Neoplasms/drug therapy , Uterine Cervical Neoplasms/genetics , 5-Methylcytosine/pharmacology , Adult , Aged , Binding Sites , Biopsy , Cohort Studies , Cytosine/chemistry , DNA/genetics , Electrophoresis, Capillary , Female , Humans , Middle Aged , Promoter Regions, Genetic , RNA, Long Noncoding , RNA, Untranslated/genetics , Reverse Transcriptase Polymerase Chain Reaction , Vasodilator Agents/pharmacology
17.
Biomed Res Int ; 2014: 467105, 2014.
Article in English | MEDLINE | ID: mdl-24818142

ABSTRACT

Female and male Wistar rats were used to determine the subchronic oral toxicities of two new ethyl-carbamates with ixodicidal activities (ethyl-4-bromphenyl-carbamate and ethyl-4-chlorphenyl-carbamate). The evaluated carbamates were administered in the drinking water (12.5, 25 and 50 mg/kg/day) for 90 days. Exposure to the evaluated carbamates did not cause mortality or clinical signs and did not affect food consumption or weight gain. However, exposure to these carbamates produced alterations in water consumption, hematocrit, percentages of reticulocytes, plasma proteins, some biochemical parameters (aspartate aminotransferase, gamma-glutamyl transpeptidase, cholinesterase, and creatinine activities), thiobarbituric acid reactive substances, and the relative weight of the spleen. Histologically, slight pathological alterations were found in the liver that were consistent with the observed biochemical alterations. The nonobserved adverse effect levels (NOAELs) of the evaluated carbamates were 12.5 mg/kg/day for both the female and male rats. The low severity and reversibility of the majority of the observed alterations suggest that the evaluated carbamates have low subchronic toxicity.


Subject(s)
Acaricides/toxicity , Toxicity Tests, Chronic , Urethane/toxicity , Animals , Body Weight/drug effects , Drinking Behavior/drug effects , Feeding Behavior/drug effects , Female , Liver/drug effects , Liver/metabolism , Liver/pathology , Male , Molecular Weight , Organ Size/drug effects , Rats, Wistar , Thiobarbituric Acid Reactive Substances/metabolism , Urethane/chemistry
18.
Biomed Res Int ; 2014: 956456, 2014.
Article in English | MEDLINE | ID: mdl-24883331

ABSTRACT

The acute oral and dermal toxicity of two new ethyl-carbamates (ethyl-4-bromophenyl-carbamate and ethyl-4-chlorophenyl-carbamate) with ixodicide activity was determined in rats. The oral LD50 of each carbamate was 300 to 2000 mg/kg, and the dermal LD50 of each carbamate was >5000 mg/kg. Clinically, the surviving rats that had received oral doses of each carbamate showed decreased weight gain (P < 0.05) and had slight nervous system manifestations. These clinical signs were evident from the 300 mg/kg dose and were reversible, whereas the 2000 mg/kg dose caused severe damage and either caused their death or was motive for euthanasia. At necropsy, these rats had dilated stomachs and cecums with diffuse congestion, as well as moderate congestion of the liver. Histologically, the liver showed slight degenerative lesions, binucleated hepatocytes, focal coagulative necrosis, and congestion areas; the severity of the lesions increased with dosage. Furthermore, an slight increase in gamma-glutamyltransferase, lactate dehydrogenase, and creatinine was observed in the plasma. The dermal application of the maximum dose (5000 mg/kg) of each carbamate did not cause clinical manifestations or liver and skin alterations. This finding demonstrates that the carbamates under study have a low oral hazard and low acute dermal toxicity.


Subject(s)
Rhipicephalus/drug effects , Skin/drug effects , Urethane/pharmacology , Administration, Oral , Animals , Creatinine/blood , Liver/drug effects , Male , Rats , Urethane/analogs & derivatives , Urethane/toxicity
19.
Open Med Chem J ; 7: 30-8, 2013.
Article in English | MEDLINE | ID: mdl-24319502

ABSTRACT

A main target in the treatment of hypertension is the angiotensin-converting enzyme (ACE). This enzyme is responsible for producing angiotensin II, a potent vasoconstrictor. Therefore, one of the targets in the treatment of hypertension is to inhibit ACE activity. Hence, this study's aim is to use computational studies to demonstrate that the proposed heterocyclic compounds have a molecular affinity for ACE and that, furthermore, these heterocyclic compounds are capable of inhibiting ACE activity, thus avoiding the production of the vasopressor Angiotensin II. All this using computer-aided drug design, and studying the systems, with the proposed compounds, through molecular recognition process and compared with the compounds already on the market for hypertension.

SELECTION OF CITATIONS
SEARCH DETAIL