Age-dependent features of CYP3A, CYP2C, and CYP2E1 functioning at metabolic syndrome

BACKGROUND

Complex investigations of cytochrome P450 (CYP) isoforms with metabolic syndrome (MS) development are limited, and specific features of adolescent's metabolisms are generally disregarded. The aim of present study was a comparative estimation of MS-mediated changes in CYP3A, CYP2C, and CYP2E1 mRNA expression and enzymatic activities, as well as antioxidant system parameters of adult and pubertal rats.

METHODS

Wistar albino male rats of two age categories [young animals of 21 days age (50-70 g) and adults (160-180 g)] were divided into four groups (eight animals in each group): (1) control 1 (intact young rats), (2) control 2 (intact adult rats), (3) MS3 (young rats with MS), and (4) MS4 (adult rats with MS). The MS was induced by full replacement of drinking water by 20% fructose solution (200 g/L). After 60 days of MS modeling, the investigation of rat liver CYP3A, CYP2C, and CYP2E1 mRNA expressions, their enzyme-marker activities, as well as the antioxidant system parameters was conducted.

RESULTS

Levels of liver CYP2E1 mRNA expression increased with MS: 40% (adults) and 80% (pubertal rats). Pubertal rats had also increased CYP3A2 mRNA expression (30%) and decreased CYP2C mRNA expression (30%). Changes in CYP2E1 and CYP2C enzymatic activities were consistent with the changes of corresponding gene expressions at both age-groups with MS. Simultaneously, liver reduced glutathione contents, and glutathione transferase and reductase activities were decreased in pubertal animals.

CONCLUSIONS

CYP isoform expression rates and glutathione system were greatly violated with MS. The greater changes were observed in pubertal rats with MS.

Repeated administration of ethambutol in therapeutic dose causes testes alteration and spermatogenesis disruption in Wistar rats

Ethambutol (EMB) is conventionally used to treat tuberculosis and atypical Mycobacterium infections in combination with other antimycobacterial drugs. Eventually, EMB testicular toxicity has not been explored extensively yet. The aim of the study is to evaluate testicular toxicity of EMB. We explored the impact of EMB on male rats' fertility, testosterone level and germ cells state, testicular pro- and anti-oxidant status and DNA damage, as well as identified EMB effects on cytochrome P-450 2E1 (CYP2E1) both with computer simulation and in vivo. We demonstrated that EMB administration to male rats decreased in epididymal sperm count (19%) and fertility index (53%). These events were accompanied by reduction in serum testosterone content (1.6 times) and appearance of spermatogenic epithelium damages. It was also found in testes the intensification of lipid peroxidation, decrease in reduced glutathione content and changes in DNA fragmentation. Additionally, computer simulation showed direct interaction of EMB with CYP2E1 active site and heme. On the top of this, we demonstrated that level of testicular CYP2E1 messenger RNA in EMB-treated rats was increased 8.7 folds and p-nitrophenol hydroxylase activity in testes rose three folds. As this shows, EMB-caused CYP2E1 induction, oxidative stress, and apoptosis in the testes contribute to inhibition of steroidogenesis enzymes and spermatogenesis disruption.

Chronic alcoholism-mediated metabolic disorders in albino rat testes

There is good evidence for impairment of spermatogenesis and reductions in sperm counts and testosterone levels in chronic alcoholics. The mechanisms for these effects have not yet been studied in detail. The consequences of chronic alcohol consumption on the structure and/or metabolism of testis cell macromolecules require to be intensively investigated. The present work reports the effects of chronic alcoholism on contents of free amino acids, levels of cytochrome P450 3A2 (CYP3A2) mRNA expression and DNA fragmentation, as well as on contents of different cholesterol fractions and protein thiol groups in rat testes. Wistar albino male rats were divided into two groups: I - control (intact animals), II - chronic alcoholism (15% ethanol self-administration during 150 days). Following 150 days of alcohol consumption, testicular free amino acid content was found to be significantly changed as compared with control. The most profound changes were registered for contents of lysine (-53%) and methionine (+133%). The intensity of DNA fragmentation in alcohol-treated rat testes was considerably increased, on the contrary CYP3A2 mRNA expression in testis cells was inhibited, testicular contents of total and etherified cholesterol increased by 25% and 45% respectively, and protein SH-groups decreased by 13%. Multidirectional changes of the activities of testicular dehydrogenases were detected. We thus obtained complex assessment of chronic alcoholism effects in male gonads, affecting especially amino acid, protein, ATP and NADPH metabolism. Our results demonstrated profound changes in testes on the level of proteome and genome. We suggest that the revealed metabolic disorders can have negative implication on cellular regulation of spermatogenesis under long-term ethanol exposure.

Correlation between spermatogenesis disorders and rat testes CYP2E1 mRNA contents under experimental alcoholism or type I diabetes

PURPOSE

The aim of the study was to investigate the correlation between spermatogenesis disorders and CYP2E1 mRNA contents in testes of rats with experimental alcoholism or type I diabetes.

MATERIAL/METHODS

Two pathological states characterized by CYP2E1 induction were simulated on Wistar male rats: experimental alcoholism and type I diabetes. As controls for each state, equal number of animals (of the same age and weight) were used. Morphological evaluation of rat testes was carried out. The spermatogenic epithelium state was estimated by four points system. CYP2E1 mRNA expression was rated by method of reverse transcriptase polymerase chain reaction. Pearson correlation coefficients were used for describing relationships between variables.

RESULTS

The presence of alcoholism and diabetes-mediated quantitative and qualitative changes in male rat spermatogenic epithelium in comparison with norm has been demonstrated. The increased levels of testes CYP2E1 have been fixed simultaneously. CYP2E1 mRNA content negatively strongly correlated with spermatogenic index value (r=-0.99; P<0.001) and positively strongly correlated with epithelium desquamation occurrence (r=0.99; P<0.001) in testes of rats with chronic alcoholism. The strong correlation between CYP2E1 mRNA content and number of spermatogonia (r=0.99; P<0.001) and "windows" occurrence (r=0.96; P<0.001) has been fixed in diabetic rats testes.

CONCLUSIONS

Present investigation has demonstrated that the testicular failure following chronic ethanol consumption and diabetes type I in male rats accompanied CYP2E1 mRNA over-expression in testes. The correlation between the levels of CYP2E1 mRNA in testes and spermatogenesis disorders allow supposing the involvement of CYP2E1 into the non-specific pathogenetic mechanisms of male infertility under above-mentioned pathologies.

Multiparameter rodent chronic model for complex evaluation of alcoholism-mediated metabolic violations

BACKGROUND

Despite of the wide spectrum of alcoholism experimental models, the majority of them are very specialized on the short list of investigated parameters and could not provide reproduction of complex metabolic changes in the rats. The aim of the present study was to estimate whether rats selected by high alcohol preference, allowed free access to 15% alcohol for 150 days, develop simultaneous multilevel disturbances of cell macromolecules structure, metabolism and oxidative/nitrosative stress.

METHODS

Wistar albino male rats were divided into groups: I - rats selected by preferences to alcohol were used for chronic alcoholism modeling by replacing water with 15% ethanol (150 days), II - control. Contents of amino acids in serum, liver mRNA CYP2E1 and CYP3A2 expression, DNA fragmentation and lipid peroxidation levels, the reduced glutathione content, superoxide dismutase, catalase, iNOS and cNOS activities were evaluated.

RESULTS

In serum of ethanol-treated rats contents of aspartic acid, serine, glycine, alanine and valine were decreased whereas contents of histidine, methionine and phenylalanine were increased. Liver CYP2E1, CYP3A2 mRNA expression, DNA fragmentation levels significantly elevated. Level of cNOS in ethanol-treated rat's hepatocytes was within the normal limits, whereas iNOS activity was raised 1.6 times. Liver pro- and anti-oxidant system alterations were shown.

CONCLUSIONS

Rats' chronic 15% alcohol consumption (150 days) led solely to complex metabolomic changes at different levels, which simultaneously characterized cell macromolecules structure, metabolism, and oxidative/nitrosative stress. Rodent model of chronic alcoholism in the proposed modification could be an adequate and reasonably priced tool for further preclinical development and testing of pharmacotherapeutic agents.

Pyrazinamide potential effects on male rats DNA fragmentation, bone type I collagen amino acid composition, reproductive capability and posterity antenatal and postnatal development

Current therapeutic regimens with first-line antitubercular agents are associated with a high rate of adverse effects which can lead to therapeutic failure. Understanding the nature and the severity of these effects is important for treatment optimization. The aim of present study was to investigate pyrazinamide potential effects on male rats DNA fragmentation, amino acid composition of bone type I collagen, reproductive capability and their posterity antenatal and postnatal development. Wistar albino male rats (160-200 g b.w.) were divided into three groups: I--received pyrazinamide per os at a dose of 1000 mg/kg b.w./day, II--at a dose of 2000 mg/kg b.w./day, in both groups it was given for 60 days; III--control. After 60 days of the experiment, rats of the experimental (groups I and II) and control groups were mated with intact virgin females. The amino acids contents of male rat bone type I collagens were determined using amino acid analyzer, epididymis and testis DNA fragmentation--electrophoretically; posterity antenatal development indices and postnatal development--by standard procedures. The study of pyrazinamide effects (administered in different doses) on males bone type I collagen amino acid contents and testis DNA fragmentation demonstrated the presence of dose-dependent pyrazinamide-mediated quantitative and qualitative changes in male rat reproductive organs DNA and extracellular matrix proteins in comparison with control. Changes in nucleic acids and proteins structure were accompanied by alterations in processes of fertilization (with intact females), embryogenesis and by lowering of posterity survival.

Pyrazinamide-mediated changes in rat type I collagen and spermatogenesis indices

Necessity of tuberculosis chemotherapy adverse effects minimization requires a comprehensive evaluation of the effects of antitubercular drugs on reproductive system and extracellular matrix proteins. Wistar albino male rats (160-200 g) were divided into three groups: I--received pyrazinamide per os at a dose of 1000 mg/kg bw/day, II--at a dose of 2000 mg/kg bw/day, in both group it was given for 60 days; III--intact animals. The contents of amino acids in rat type I collagens were determined using an amino acid analyzer. Morphological analyses were carried out by an optical microscope. The study of the effects of pyrazinamide administered in different doses on type I collagen amino acid contents, testis cells morphologic and morphometric parameters and spermatogenesis demonstrated the presence of pyrazinamide-mediated quantitative and qualitative changes in male rat reproductive organs, spermatogenic epithelial cells and extracellular matrix proteins in comparison with norm.The largest number of changes were established at a dose 2000 mg/kg b.w./day. The observed collagen molecules changes could hence affect the properties and correct functioning of spermatogenic epithelium and other tissues of reproductive organs. They might be caused by pyrazinamide via cytochrome P450 2E1 induction, reactive oxygen species production or direct action of this compound on protein biosynthesis processes.