Effect of chronic heroin and cocaine administration on global DNA methylation in brain and liver.

Drug abuse is associated with epigenetic changes, such as histone modifications and DNA methylation. The purpose of the present study was to examine the effect of chronic cocaine and heroin administration on global DNA methylation in brain and liver. Male, 8 week old, C57BL/6J mice received heroin in a chronic 'intermittent' escalating dose paradigm, or cocaine in a chronic escalating dose 'binge' paradigm, which mimic the human pattern of opioid or cocaine abuse respectively. Following sacrifice, livers and brains were removed and DNA was extracted from them. The extracted DNA was hydrolyzed and 2'-deoxycytidine and 5-methyl-2'-deoxycytidine were determined by HPLC-UV. The % 5-methyl-2'-deoxycytidine content of DNA was significantly higher in the brain compared to the liver. There were no differences between the control animals and the cocaine or heroin treated animals in neither of the tissues examined, which is surprising since cocaine administration induced gross morphological changes in the liver. Moreover, there was no difference in the % 5-methyl-2'-deoxycytidine content of DNA between the cocaine and the heroin treated animals. The global DNA methylation status in the brain and liver of mice chronically treated with cocaine or heroin remains unaffected, but this finding cannot exclude the existence of anatomical region or gene-specific methylation differences. This is the first time that global DNA methylation in the liver and whole brain has been studied following chronic cocaine or heroin treatment.

Alterations in serum MMP and TIMP concentrations following chronic heroin abuse.

UNLABELLED: Abstract Context: Although opiate abuse is known to affect matrix metalloproteinases (MMPs), data on these enzymes and their tissue inhibitors in heroin addicts are scarce. OBJECTIVE: In the present study, we determined serum concentrations of MMP-2, MMP-9, tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in heroin users, and compared them with healthy individuals. We evaluated whether 21 d of abstinence are adequate to reverse the effect of opiates and we compared seropositive with seronegative, for anti-HCV antibodies, heroin users. MATERIALS AND METHODS: Twenty-six heroin-dependent male volunteers and an equal number of healthy individuals participated in this study. ELISA was used to assess the serum levels of MMP-2, MMP-9, TIMP-1 and TIMP-2. Heroin users were assessed both upon admission and upon completion of a 21-d detoxification program. RESULTS: Serum TIMP-1 concentrations were significantly lower and the ratios MMP-2/TIMP-1, MMP-9/TIMP-1 and MMP-2/TIMP-2 were significantly higher in heroin users compared to healthy individuals. Heroin users who were seropositive had lower MMP concentrations, as well as lower MMP/TIMP ratios, compared to those who were seronegative. DISCUSSION: Our results showed that in heroin-addicted individuals, and especially those who are positive for anti-HCV antibodies, the balance between MMPs and TIMPs in serum is disrupted and this disruption cannot be restored within 21 d of abstinence. CONCLUSION: Chronic heroin abuse disrupts the balance between MMPs and TIMPs in serum and this effect is not reversible within 21 d of abstinence.

Disposable pipette extraction for gas chromatographic determination of codeine, morphine, and 6-monoacetylmorphine in vitreous humor.

The availability of a sensitive and rapid analytical method for the determination of opiates, and other substances of forensic interest, in a variety of biological specimens is of utmost importance to forensic laboratories. Solid-phase extraction is very popular in the pre-treatment of forensic samples. Nevertheless, a new approach, disposable pipette extraction (DPX), is gaining increasing interest in sample preparation. DPX has already been applied to the analysis of drugs of abuse in common biological matrices, such as urine and blood, but has not yet been evaluated on alternative biological samples, such as vitreous humor. The objective of this study was to evaluate the applicability of DPX on the analysis of opiates in vitreous humor. The currently developed method is fast, reliable, and easy to perform. The sensitivity, precision, and accuracy are satisfactory. Recoveries obtained are within the range of 72-91%, whereas the sample volume of vitreous humor required is only 100 µL.

Epigenetic mechanisms in metal toxicity.

The true understanding of epigenetics evolved over time as our knowledge on DNA methylation and chromatin modifications and their effects on gene expression increased. The current flurry of research on epigenetics and the increasing documentation of the effects of various environmental factors on DNA methylation, chromatin modification, as well as on the expression of small non-coding RNAs (ncRNAs) have expanded the scope of research on the etiology of various diseases including cancer. The current review briefly discusses various molecular mechanisms of epigenetic regulation of gene expression, and expands the discussion with examples of heavy metal-induced alterations of gene expression and the associated epigenetic changes.

Evaluation of prooxidant-antioxidant balance in chronic heroin users in a single assay: an identification criterion for antioxidant supplementation.

BACKGROUND: Opiate abuse has been linked to oxidative stress, through the separate evaluation of oxidants and antioxidants. OBJECTIVES: To determine prooxidant-antioxidant balance (PAB) in chronic heroin users in a single assay, easily applied in a clinical setting. Specifically, to examine whether PAB values correlate with the duration of abuse or with the presence of anti-HCV antibodies. METHODS: Sixty-four chronic heroin users - 34 cases and 30 controls - participated in this study. PAB was determined by an Enzyme-linked immunosorbent assay (ELISA) method, developed by members of the study group. RESULTS: In heroin users, oxidative balance was disrupted in favor of prooxidants. There was no correlation of PAB values with the duration of abuse or with the presence of anti-Hepatitis C virus (HCV) antibodies. CONCLUSIONS: Chronic heroin users can benefit from an antioxidant therapy, and the method currently presented can be used as an identification criterion.

Isoprostane as a marker of oxidative stress in chronic heroin users: correlation with duration of heroin use or concomitant hepatitis C infection.

BACKGROUND: Although chronic heroin abuse has been extensively linked to oxidative stress, and while plasma 15-F(2t)-IsoP is considered a good indicator of oxidative stress, there remain few references in the literature about the plasma concentration of this marker in heroin dependent subjects. OBJECTIVES: To determine plasma 15-F(2t)-IsoP, as a marker of oxidative stress, in chronic heroin users, and to examine whether the values of this marker correlate with the duration of heroin use or with the presence of anti-HCV antibodies. METHODS: Forty-two chronic heroin users and twenty two healthy control subjects were recruited for this study. An enzyme-immunoassay method was used for the determination of 15-F(2t)-IsoP in plasma. RESULTS: Plasma 15-F(2t)-IsoP values were significantly higher in chronic heroin users compared to healthy controls. No correlation was found between the values of plasma 15-F(2t)-IsoP and the duration of heroin use. Heroin dependent subjects positive for anti-HCV antibodies had significantly lower values of plasma 15-F(2t)-IsoP as compared to those without a history of HCV infection. CONCLUSIONS: The elevated plasma 15-F(2t)-IsoP values in heroin dependent subjects, compared to healthy individuals, indicate a shift of the balance between oxidants and antioxidants towards the former and suggest that heroin dependent subjects could benefit from an antioxidant therapy.

Neuropathological findings in Dandy Walker variant.

OBJECTIVE: Dandy-Walker malformation is a congenital malformation that is characterized by hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle and enlargement of the posterior fossa. The aim of the study is to describe the morphological and morphometric alterations of neurons (in various regions of the brain) in a case of Dandy-Walker Variant. METHODS: By Golgi method and routine techniques, the alterations in the brain of a 23 years old case of Dandy-Walker Variant who died accidentally were studied. Furthermore, a detailed morphometric analysis of neuronal parameters and a statistical comparison with an age-matched control were applied. RESULTS: In the cerebellum the morphological study, apart from gliosis, revealed reduction of the size of cell body and poverty of dendritic arborization with loss of dendritic branches and spines. In the cerebral cortex and the hippocampus the most prominent findings were the tortuous configuration of the apical dendrites of the pyramidal neurons, the focal swellings of the axons and the dendrites and significant gliosis. CONCLUSION: Although the gross anatomical examination of the brain demonstrated only mild neurodevelopmental anomalies (except the key features of the syndrome), the microscopic examination revealed significant morphological alterations of neurons and dendrites.