Aging in psoriasis vulgaris: female patients are epigenetically older than healthy controls.

BACKGROUND: Psoriasis vulgaris is a skin autoimmune disease. Psoriatic patients have significantly lowered life expectancy and suffer from various comorbidities. The main goal of the study was to determine whether psoriatic patients experience accelerated aging. As accelerated aging might be the reason for the higher prevalence of comorbidities at lower chronological ages, we also wanted to investigate the relationship between aging and selected parameters of frequent psoriatic comorbidities - endocan, vascular endothelial growth factor and interleukin-17. Samples were obtained from 28 patients and 42 healthy controls. Epigenetic age measurement was based on the Horvath clock. The levels of endocan, vascular endothelial growth factor and interleukin-17 were analyzed using standardized ELISA methods. RESULTS: The difference between the epigenetic age and the chronological age of each individual subject did not increase with the increasing chronological age of patients. We cannot conclude that psoriasis causes accelerated aging. However, the epigenetic and chronological age difference was significantly higher in female patients than in female controls, and the difference was correlated with endocan (r = 0.867, p = 0.0012) and vascular endothelial growth factor (r = 0.633, p = 0.0365) only in female patients. CONCLUSIONS: The findings suggest a possible presence of pathophysiological processes that occur only in female psoriatic patients. These processes make psoriatic females biologically older and might lead to an increased risk of comorbidity occurrence. This study also supports the idea that autoimmune diseases cause accelerated aging, which should be further explored in the future.

Alarmins HMGB1, IL-33, S100A7, and S100A12 in Psoriasis Vulgaris.

BACKGROUND: Psoriasis vulgaris is a chronic autoimmune disease associated with systemic inflammation. Increased levels of numerous cytokines, chemokines, growth factors, and other molecules were found in the skin and in the circulation of psoriatic patients. Alarmins, also known as danger signals, are intracellular proteins, which are released to an extracellular space after infection or damage. They are the markers of cell destructive processes. OBJECTIVE: The aim of the present study was to evaluate the suitability of selected alarmins (HMGB1, IL-33, S100A7, and S100A12) as potential biomarkers of severity of psoriasis and to explore possible relationships between these proteins for the purpose of better understanding their roles in the immunopathology of psoriasis. METHODS: The serum levels of selected alarmins were measured in 63 psoriatic patients and 95 control individuals. The levels were assessed by the ELISA technique using commercial kits. The data were statistically processed with MedCalc version 19.0.5. RESULTS: In psoriatic patients, we found significantly increased levels of HMGB1 (p < 0.05), IL-33 (p < 0.01), S100A7 (p < 0.0001), and S100A12 (p < 0.0001). In addition, we found a significant relationship between HMGB1 and S100A7 (Spearman's rho = 0.276, p < 0.05) in the patients and significant relationship between HMGB1 and IL-33 in the controls (Spearman's rho = 0.416, p < 0.05). We did not find any relationship between observed alarmins and the disease severity. CONCLUSIONS: The alarmins HMGB1, IL-33, S100A7, and S100A12 were significantly elevated in the serum of patients, which states the hypothesis that they play specific roles in the immunopathology of psoriasis. However, we have not yet found a relationship between observed alarmins and the disease severity. The discovery of the relationship between HMGB1 and S100A7 is a novelty that should be studied in the future to further clarify its role and importance.

Metabolic Syndrome, Clusterin and Elafin in Patients with Psoriasis Vulgaris.

BACKGROUND: Psoriasis is a pathological condition characterized by immune system dysfunction and inflammation. Patients with psoriasis are more likely to develop a wide range of disorders associated with inflammation. Serum levels of various substances and their combinations have been associated with the presence of the disease (psoriasis) and have shown the potential to reflect its activity. The aim of the present study is to contribute to the elucidation of pathophysiological links between psoriasis, its pro-inflammatory comorbidity metabolic syndrome (MetS), and the expression of clusterin and elafin, which are reflected in the pathophysiological "portfolio" of both diseases. MATERIAL AND METHODS: Clinical examinations (PASI score), ELISA (clusterin, elafin), and biochemical analyses (parameters of MetS) were performed. RESULTS: We found that patients with psoriasis were more often afflicted by MetS, compared to the healthy controls. Clusterin and elafin levels were higher in the patients than in the controls but did not correlate to the severity of psoriasis. CONCLUSION: Our data suggest that patients with psoriasis are more susceptible to developing other systemic inflammatory diseases, such as MetS. The levels of clusterin and elafin, which are tightly linked to inflammation, were significantly increased in the patients, compared to the controls, but the presence of MetS in patients did not further increase these levels.

Goeckerman Therapy of Psoriasis: Genotoxicity, Dietary Micronutrients, Homocysteine, and MTHFR Gene Polymorphisms.

Goeckerman therapy (GT) of psoriasis vulgaris is based on the application of crude coal tar and ultraviolet radiation. We investigated DNA damage by the number of micronucleated binucleated cells (MNBC) in lymphocytes, serum homocysteine, vitamin B12, folic acid, and two polymorphisms (C677T and A1298C) in the MTHFR gene in 35 patients with exacerbated psoriasis vulgaris classified according to the psoriasis area and severity index (PASI) score and treated by GT. The median of PASI score decreased from nineteen to five, and MNBC increased from 10 to 18‰ after GT (p < 0.001 in both cases). Correlations of MNBC with homocysteine (Spearman's rho = 0.420, p = 0.012) and vitamin B12 (rho = -0.389, p = 0.021) before the therapy were observed. Hyperhomocysteinemia was an independent predictor of genotoxicity (OR 9.91; 95% CI, 2.09-55.67; p = 0.003). Homocysteine was higher in females than in males (13 vs. 12 µmol/L, p = 0.045). In contrast, vitamin B12 levels in the females were lower than in the males (160 vs. 192 pmol/L, p = 0.047). Vitamin B12 in the females were negatively influenced by smoking status (160 pmol/L in smokers vs. 192 pmol/L in non-smokers, p = 0.025). A significantly higher MNBC was found in CC homozygous patients (A1298C polymorphism) than in AC heterozygotes (32 vs. 16‰, p = 0.005) and AA homozygotes (32 vs. 18‰, p = 0.036). Our data showed that homocysteine participates in the pathogenesis of psoriasis. Its serum levels correlated with MNBC and allowed the prediction of DNA damage to appear within GT. Both micronutrients status and homocysteine metabolic pathway contribute to the genotoxicity of GT.

Carrier molecules and extraction of circulating tumor DNA for next generation sequencing in colorectal cancer.

The aims of the study were: i) to compare circulating tumor DNA (ctDNA) yields obtained by different manual extraction procedures, ii) to evaluate the addition of various carrier molecules into the plasma to improve ctDNA extraction recovery, and iii) to use next generation sequencing (NGS) technology to analyze KRAS, BRAF, and NRAS somatic mutations in ctDNA from patients with metastatic colorectal cancer. Venous blood was obtained from patients who suffered from metastatic colorectal carcinoma. For plasma ctDNA extraction, the following carriers were tested: carrier RNA, polyadenylic acid, glycogen, linear acrylamide, yeast tRNA, salmon sperm DNA, and herring sperm DNA. Each extract was characterized by quantitative real-time PCR and next generation sequencing. The addition of polyadenylic acid had a significant positive effect on the amount of ctDNA eluted. The sequencing data revealed five cases of ctDNA mutated in KRAS and one patient with a BRAF mutation. An agreement of 86% was found between tumor tissues and ctDNA. Testing somatic mutations in ctDNA seems to be a promising tool to monitor dynamically changing genotypes of tumor cells circulating in the body. The optimized process of ctDNA extraction should help to obtain more reliable sequencing data in patients with metastatic colorectal cancer.

Droplet Digital PCR Analysis of GSTM1 Deletion Polymorphism in Psoriatic Subjects Treated with Goeckerman Therapy.

Goeckerman therapy (GT) represents an effective treatment of psoriasis including a combination of pharmaceutical grade crude coal tar (CCT) and ultraviolet irradiation (UV-R). Coal tar contains a mixture of polycyclic aromatic hydrocarbons. The best known carcinogenic polyaromate - benzo[a]pyrene is metabolized into a highly reactive benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE). Glutathione S-transferase M1 (GSTM1) catalyses the conjugation of drugs, toxins and products of oxidative stress with glutathione. The aim of the study is to found possible associations between GSTM1 genotypes and the level of BPDE-DNA adducts in 46 psoriatic patients treated with GT. For genotyping, droplet digital PCR was applied. The GSTM1 copy number was normalized to ß-globin reference gene. In five GSTM1*1/*1 subjects, the GSTM1 to ß-globin ratio moved from 0.99 to 1.03 with a median of 1.01. GSTM1*0/*1 heterozygotes (n = 20) contained only one GSTM1 function allele which conditioned the ratio 0.47-0.53 (median 0.50). GSTM1*0/*0 individuals (n = 21) showed no amplification of the null variants because of the large deletion in GSTM1. BPDE-DNA concentrations ranged from 1.8 to 66.3 ng/µg with a median of 12.3 ng/µg. GSTM1*0/*0 and GSTM1*0/*1 genotypes showed non-significantly higher concentrations of BPDE-DNA adducts than the GSTM1*1/*1 one (12.3 and 12.4 vs 7.8 ng/µg). The non-significant relationship between BPDE-DNA adducts and GSTM1 genotypes in psoriatic patients could be associated with relatively low doses of CCT and short-term UV-R exposures used in GT.

Telomere length, oxidative and epigenetic changes in blood DNA of patients with exacerbated psoriasis vulgaris.

BACKGROUND: The pathogenesis of psoriasis vulgaris involves changes in DNA molecules, genomic instability, telomere attrition, and epigenetic alterations among them. These changes are also considered important mechanisms of aging in cells and tissues. OBJECTIVE: This study dealt with oxidation damage, telomere length and methylation status in DNA originating from peripheral blood of 41 psoriatic patients and 30 healthy controls. METHODS: Oxidative damage of serum DNA/RNA was determined immunochemically. Real-time PCR was used for the analysis of the telomere length. ELISA technique determined levels of 5-methylcytosine in blood cells' DNA. RESULTS: Oxidative damage of serum DNA/RNA was higher in patients than in controls (median, 3758 vs. 2286pg/mL, p<0.001). A higher length of telomeres per chromosome was found in patients whole-cell DNA than in controls (3.57 vs. 3.04 kilobases, p=0.011). A negative correlation of the length of telomeres with an age of the control subjects was revealed (Spearman's rho=-0.420, p=0.028). Insignificantly different levels of 5-methylcytosine in patients and controls were observed (33.20 vs. 23.35%, p=0.234). No influences of sex, smoking, BMI, PASI score, and metabolic syndrome on the methylation status were found. STUDY LIMITATIONS: i) A relatively small number of the participants, particularly for reliable subgroup analyses, ii) the Caucasian origin of the participants possibly influencing the results of the parameters determined, and iii) Telomerase activity was not directly measured in serum or blood cells. CONCLUSION: The study demonstrated increased levels of oxidized DNA/RNA molecules in the serum of patients with exacerbated psoriasis vulgaris. The results were minimally influenced by sex, the presence of metabolic syndrome, or cigarette smoking. In the psoriatic blood cells' DNA, the authors observed longer telomeres compared to healthy controls, particularly in females. Insignificantly higher global DNA methylation in psoriasis cases compared to the controls indicated marginal clinical importance of this epigenetic test performed in the blood cells' DNA.

Dopamine 2 receptor expression in various pathological types of clinically non-functioning pituitary adenomas.

Clinically non-functioning pituitary adenomas account for about one-third of pituitary tumors. The majority of them are pathologically classified as gonadotropinomas or null-cell adenomas without hormonal expression. The rest represent silent corticotroph adenomas and plurihormonal tumors. Conservative therapy with dopamine agonists is effective in some cases only depending on the expression of dopamine 2 receptors (D2R). The aim of this study was to quantitatively estimate D2R expression in clinically non-functioning pituitary adenomas and correlate the results with adenoma type according to pathological classification. Out of the 87 adenomas investigated, 63 expressed gonadotropins, 7 were silent corticotroph adenomas, 7 were plurihormonal tumors, and only 6 did not express any pituitary hormone on immunohistochemical investigation. With the use of the reverse transcriptase PCR technique, D2R mRNA was expressed in all adenomas with very heterogeneous quantity. The expression was very low in corticotroph adenomas (relative median quantity after normalization to housekeeping gene 0.01) and lower in plurihormonal tumors (median 0.4) than in gonadotroph (median 1.3) and null-cell adenomas (median 1.9). The difference between corticotroph adenomas and plurihormonal tumors in comparison with other pathological types was statistically significant. The expression of D2R did not depend on the presence or absence of gonadotropins. We conclude that D2R expression is very low in corticotroph adenomas and significantly lower in plurihormonal tumors. The positivity of gonadotropins does not predict the D2R quantity.

Polyadenylated sequencing primers enable complete readability of PCR amplicons analyzed by dideoxynucleotide sequencing.

Dideoxynucleotide DNA sequencing is one of the principal procedures in molecular biology. Loss of an initial part of nucleotides behind the 3' end of the sequencing primer limits the readability of sequenced amplicons. We present a method which extends the readability by using sequencing primers modified by polyadenylated tails attached to their 5' ends. Performing a polymerase chain reaction, we amplified eight amplicons of six human genes (AMELX, APOE, HFE, MBL2, SERPINA1 and TGFB1) ranging from 106 bp to 680 bp. Polyadenylation of the sequencing primers minimized the loss of bases in all amplicons. Complete sequences of shorter products (AMELX 106 bp, SERPINA1 121 bp, HFE 208 bp, APOE 244 bp, MBL2 317 bp) were obtained. In addition, in the case of TGFB1 products (366 bp, 432 bp, and 680 bp, respectively), the lengths of sequencing readings were significantly longer if adenylated primers were used. Thus, single strand dideoxynucleotide sequencing with adenylated primers enables complete or near complete readability of short PCR amplicons.

[The importance of DNA analysis of C282Y, H63D and S65C mutations in the HFE gene]. / Význam DNA vysetrení mutací C282Y, H63D a S65C v HFE genu.

BACKGROUND: Hereditary hemochromatosis is a relatively common genetic disease characterized by increased iron absorption and deposition in major organs of the body. The aim of this study was to determine the prevalence of C282Y, H63D and S65C mutations in the HFE gene in patients suspected of hereditary hemochromatosis and to compare it with healthy subjects (control group). MATERIAL AND METHODS: The group of patients consisted of 95 males and 45 females (median age 55 years, range 20 to 83 years). The control group was represented by 167 volunteers of Caucasian origin (65 males and 102 females, median age 25 years, range 18 to 62 years). The PCR/RFLP genetic analysis was used to detect mutations in the HFE gene. RESULTS: Allelic frequencies of C282Y, H63D, and S65C in the groups of patients were 18.2 %, 17.5 %, and 1.8 %, respectively. The frequencies of the alleles in the control group were 5.7 % (C282Y), 12.3 % (H63D), and 0.6 % (S65C). CONCLUSIONS: Our results show significant differences in the frequency of C282Y mutation between the patients suspected of hereditary hemochromatosis and the control group (18.2 % vs. 5.7 %). The prevalence of H63D and S65C mutations in both groups was not statistically significant.

Lack of association between the Val158Met catechol-O-methyltransferase gene polymorphism and methamphetamine dependence.

OBJECTIVES: About 25,000 serious methamphetamine abusers live in the Czech Republic among the total population of 10 million. Dependence on methamphetamine is markedly related to the brain neurotransmitter dopamine, metabolised by catechol-O-methyltransferase enzyme. The main aim of the study was to ascertain whether the Val158Met catechol-O-methyltransferase gene polymorphism is associated with methamphetamine dependence in this Central European country. METHODS: One hundred and twenty-three subjects dependent on methamphetamine (women N=44), parents of sixty-seven dependent individuals, and four hundred healthy controls (women N=250) were involved into the study. We performed a population-based as well as family-based genetic association studies. RESULTS: We did not find any significant association between the Val158Met catechol-O-methyltransferase gene polymorphism and methamphetamine dependence using the population-based or family-based design (p=0.41-0.66; Chi-Square Test or UNPHASED program, Version 3.1.4, respectively). We found a trend toward a statistically significant difference between the Val allele carriers and Met/Met homozygotes in the frequence of psychotic symptoms induced by methamphetamine (more frequent in Val carriers; p=0.062; Chi-Square Test). CONCLUSION: Further research involving haplotype analysis and other dopamine-related genetic polymorphisms in large populations is needed. More attention should also be paid to possible role of the Val158Met catechol-O-methyl-transferase gene polymorphism in individual clinical subtypes of dependence on methamphetamine involving e.g. psychotic features or violence.

Analysis of D1853N ATM polymorphism in radiosensitive patients with cervical carcinoma.

UNLABELLED: Clinical oncologists have been focusing their efforts on attempting to define risk groups of patients with unusual biological reactions to the recommended therapy regimens using molecular biology techniques. THE AIMS OF OUR STUDY WERE: (i) to find a design and validate a method for fast and reliable analysis of the D1853N (5557G>A) genetic polymorphism in the ATM (ataxia-telangiectasia mutated) gene; (ii) to use side-directed mutagenesis to generate ATM 5557A-positive DNA (reference ATM5557A DNA); and (iii) to analyze a group of patients suffering from cervical carcinoma with adverse responses to radiotherapy. The 5557A variant was found in three of twenty women (15%). Our data show that the prevalence of the 5557A allelic variant in cervical cancer subjects with adverse responses after irradiation probably does not differ from the prevalence common in Caucasians. A larger population study should confirm these preliminary results.

[KRAS mutation testing in therapeutic algorithm for treatment of metastatic colorectal carcinoma]. / Vysetrení mutacního statutu genu KRAS jako soucást algoritmu lécby metastatického kolorektálního karcinomu.

Targeted therapy has become an integral part of treatment procedures of malignant tumors. Colorectal carcinomas are frequently targeted with monoclonal anti-EGFR antibodies (cetuximab and panitumumab). Activating somatic mutations in codons 12 and 13 of the exon 2 of KRAS gene are considered negative predictive factors of response to anti-EGFR therapy in patients with metastatic colorectal cancer. In the Czech Republic, evaluation of mutational status of KRAS gene is performed in several referral laboratories. In 2009, these laboratories performed 2580 tests of the KRAS mutational status--out of these, 60.2% cases reported non-mutated, wild-type KRAS. In one of the referral laboratories, we demonstrate the logistics of KRAS testing procedure. Stratification of patients with metastatic colorectal tumors based on their KRAS mutational status has evolved to a standard procedure. Laboratories performing these methods shall therefore adhere to the recommendations of the professional and accredited societies.

Simple capacitor-switch model of excitatory and inhibitory neuron with all parts biologically explained allows input fire pattern dependent chaotic oscillations.

Due to known information processing capabilities of the brain, neurons are modeled at many different levels. Circuit theory is also often used to describe the function of neurons, especially in complex multi-compartment models, but when used for simple models, there is no subsequent biological justification of used parts. We propose a new single-compartment model of excitatory and inhibitory neuron, the capacitor-switch model of excitatory and inhibitory neuron, as an extension of the existing integrate-and-fire model, preserving the signal properties of more complex multi-compartment models. The correspondence to existing structures in the neuronal cell is then discussed for each part of the model. We demonstrate that a few such inter-connected model units are capable of acting as a chaotic oscillator dependent on fire patterns of the input signal providing a complex deterministic and specific response through the output signal. The well-known necessary conditions for constructing a chaotic oscillator are met for our presented model. The capacitor-switch model provides a biologically-plausible concept of chaotic oscillator based on neuronal cells.

Analysis of Risk Factors of Stroke and Venous Thromboembolism in Females With Oral Contraceptives Use.

Thrombotic diathesis has been a well-known complication of oral contraceptive use for more than 50 years. This is true not only for venous thrombosis but also for an arterial one. The etiology is usually multifactorial and depends on several additional risk factors. We analyzed the prevalence of inherited and acquired thrombophilia in a cohort of 770 females who had a thrombotic event in association with oral contraceptive use (700 women with venous thromboembolism [VTE], 70 with stroke). Moreover, we tried to identify additional risk factors. Inherited thrombophilia was found in 44.5% with higher frequency in the cohort with VTE (42%) than in females with stroke (24%). The most frequent finding was factor V Leiden. Cigarette smoking was significantly more frequent in the group with stroke (50% vs 25%). The prevalence of cigarette smoking in the group with VTE did not exceed the frequency in general population. Women on oral contraceptive pills have higher risk of venous as well as arterial thrombosis. The risk of venous thrombosis is increased in females with inherited thrombophilia, whereas those with some additional acquired risk factors (especially smoking) may be predisposed to arterial thrombosis. However, the absolute risk of thrombosis in healthy women is low, far less than the risk of unintended pregnancy. Moreover, the risk may be reduced by keeping some rules before the prescription of the pills, healthy life style, and a proper choice of contraception.

Telomere length, oxidative and epigenetic changes in blood DNA of patients with exacerbated psoriasis vulgaris

Abstract Background The pathogenesis of psoriasis vulgaris involves changes in DNA molecules, genomic instability, telomere attrition, and epigenetic alterations among them. These changes are also considered important mechanisms of aging in cells and tissues. Objective This study dealt with oxidation damage, telomere length and methylation status in DNA originating from peripheral blood of 41 psoriatic patients and 30 healthy controls. Methods Oxidative damage of serum DNA/RNA was determined immunochemically. Real-time PCR was used for the analysis of the telomere length. ELISA technique determined levels of 5-methylcytosine in blood cells' DNA. Results Oxidative damage of serum DNA/RNA was higher in patients than in controls (median, 3758 vs. 2286 pg/mL, p < 0.001). A higher length of telomeres per chromosome was found in patients whole-cell DNA than in controls (3.57 vs. 3.04 kilobases, p = 0.011). A negative correlation of the length of telomeres with an age of the control subjects was revealed (Spearman's rho = -0.420, p = 0.028). Insignificantly different levels of 5-methylcytosine in patients and controls were observed (33.20 vs. 23.35%, p = 0.234). No influences of sex, smoking, BMI, PASI score, and metabolic syndrome on the methylation status were found. Study limitations i) A relatively small number of the participants, particularly for reliable subgroup analyses, ii) the Caucasian origin of the participants possibly influencing the results of the parameters determined, and iii) Telomerase activity was not directly measured in serum or blood cells. Conclusion The study demonstrated increased levels of oxidized DNA/RNA molecules in the serum of patients with exacerbated psoriasis vulgaris. The results were minimally influenced by sex, the presence of metabolic syndrome, or cigarette smoking. In the psoriatic blood cells' DNA, the authors observed longer telomeres compared to healthy controls, particularly in females. Insignificantly higher global DNA methylation in psoriasis cases compared to the controls indicated marginal clinical importance of this epigenetic test performed in the blood cells' DNA.

Changes in circulating cell-free DNA and nucleosomes in patients with exacerbated psoriasis.

Psoriasis is a multifactorial chronic inflammatory disease. We aimed to examine blood levels of nucleosomes derived from apoptotic cells, nucleosomal cell-free DNA (cfDNA) and immune-inflammatory biomarkers tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and interleukin 6 (IL-6) in psoriatic subjects. The study included 28 patients with exacerbated psoriasis vulgaris and 22 controls. The clinical and laboratory investigations included the determination of PASI score, BMI, cfDNA (by real-time PCR), nucleosomes, TNF-α, CRP, and IL-6. The range of PASI score in psoriatic patients was 10-34 (median 19). In the patients, we found significantly elevated levels (p < 0.001) of cfDNA, nucleosomes, TNF-α, CRP, and IL-6. We did not find any significant relationship between the analyzed parameters in either group (i.e., experimental or control). Elevated levels of the biomarkers of inflammation (TNF-α, CRP, and IL-6) and the indicators of apoptosis (cfDNA, circulating nucleosomes) proved that exacerbated psoriasis vulgaris is associated with a high degree of systemic inflammatory responses and dysregulated apoptotic pathways.

The COMT Val158Met polymorphism is associated with novelty seeking in Czech methamphetamine abusers: preliminary results.

OBJECTIVES: Measurable traits of human personality may mark the predisposition to psychopathology. Increased novelty seeking plays an important role in the pathogenesis of substance abuse. Novelty seeking, one of the fundamental traits of the human temperament, is related to dopamine. Catechol-O-methyltransferase (COMT) is essential for dopamine inactivation. The aim of our study was to assess whether the COMT gene Val158Met functional polymorphism in patients dependent on methamphetamine is related to their novelty seeking score. METHODS: Patients dependent on methamphetamine who had been treated at the Addiction Treatment Unit in Nechanice in 2004 and 2005 agreed to participate in the investigation. We administered the Temperament and Character Inventory (TCI) questionnaire, assessed their novelty seeking score and analysed their DNA samples for COMT Val158Met genotype. RESULTS: The subjects were thirty-seven Czech Caucasians (women N=10) dependent on methamphetamine with an average age of 23.6+/-3.8 years. We found a significantly higher mean novelty seeking score among the patients with the Met allele (Met/Met homozygotes+Val/Met heterozygotes; N=28) than in nine Val/Val homozygotes (27.4 vs 24.1; p=0.042, Two-Sample T-Test). CONCLUSION: The Met allele of the COMT gene Val158Met polymorphism is associated with low COMT enzyme activity and high endogenous dopamine synaptic levels in the prefrontal cortex. This leads to a decrease in dopaminergic neurotransmission in nucleus accumbens and a need for an increased activity to stimulate it. Novelty seeking behavior corresponds with this need.

Glycation and advanced glycation end-products in laboratory experiments in vivo and in vitro.

The purpose of our study was to determine the amount of glycated proteins and advanced glycation end products (AGE) in cataractous lens homogenates of patients who underwent phacoemulsification, and to define a simple in vitro protein model of glycoxidation. Analysis of 30 cataractous lenses (15 diabetic and 15 non-diabetic) revealed a significant increase in both glycated lens proteins of diabetics compared with the controls (0.15 vs 0.08 nmol/mg protein, P < 0.01) and AGE-linked fluorescence at 440 nm (4.8 vs 2.8 AU/mg protein, P < 0.01). The presence of AGE fluorescence in lenses indicates the role of oxidative stress in cataractogenesis. Fifty-six days incubation of alanine and aspartate aminotransferases, used as model proteins, with 500 mM D-fructose at 25 and 37 degrees C led to a complete inhibition of ALT and AST activities. The fluorescence of both aminotransferases rose according to the chosen incubation temperature: 37 degrees C > 25 degrees C > 4 degrees C. ALT and AST incubated in a medium containing D-fructose are subject to nonenzymatic glycation followed by a consequent formation of AGE products. Our data: i) support the concept of glycation-glycoxidation pathway appearing in diabetic patients; ii) form a base for determination of the efficiency of various antioxidative compounds in vitro.

Genetic polymorphisms in biotransformation enzymes for benzo[a]pyrene and related levels of benzo[a]pyrene-7,8-diol-9,10-epoxide-DNA adducts in Goeckerman therapy.

Goeckerman therapy (GT) for psoriasis combines the therapeutic effect of crude coal tar (CCT) and ultraviolet radiation (UVR). CCT contains polycyclic aromatic hydrocarbons, some of which can form DNA adducts that may induce mutations and contribute to carcinogenesis. The aim of our work was to evaluate the relationship between concentrations of benzo[a]pyrene-7,8-diol-9,10-epoxide-DNA adducts (BPDE-DNA adducts) and rs4646903 (CYP1A1 gene), rs1048943 (CYP1A1), rs1056836 (CYP1B1), rs1051740 (EPHX1), rs2234922 (EPHX1) and rs8175347 (UGT1A1) polymorphic sites, and GSTM1 null polymorphism in 46 patients with chronic stable plaque psoriasis who underwent GT. The level of BPDE-DNA adducts was determined using the OxiSelect BPDE-DNA Adduct ELISA Kit. Polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis (rs4646903, rs1048943, rs1051740, and rs2234922), fragment analysis (rs8175347), real-time PCR (rs1056836), and digital droplet PCR polymorphism (GSTM1) were used. CYP1B1*1/*1 wild-type subjects and CYP1B1*3/*1 heterozygotes for rs1056836 formed significantly higher amounts of BPDE-DNA adducts than CYP1B1*3/*3 homozygotes (p=0.031 and p=0.005, respectively). Regarding rs1051740, individuals with EPHX1*3/*1 heterozygosity revealed fewer adducts than EPHX1*1/*1 wild-type subjects (p=0.026). Our data suggest that CYP1B1/EPHX1 genotyping could help to predict the risk of DNA damage and to optimize doses of coal tar and UVR exposure in psoriatic patients in whom GT was applied.