Quantitation of cytochrome P450 mRNAs in patients with suspected liver diseases as assessed by reverse transcriptase-polymerase chain reaction

Update information on drug metabolism systems--2009, part II: summary of information on the effects of diseases and environmental factors on human cytochrome P450 (CYP) enzymes and transporters

The present paper is an update of the data on the effects of diseases and environmental factors on the expression and/or activity of human cytochrome P450 (CYP) enzymes and transporters. The data are presented in tabular form (Tables 1 and 2) and are a continuation of previously published summaries on the effects of drugs and other chemicals on CYP enzymes (Rendic, S.; Di Carlo, F. Drug Metab. Rev., 1997, 29(1-2), 413-580., Rendic, S. Drug Metab. Rev., 2002, 34(1-2), 83-448.). The collected information presented here is as stated by the cited author(s), and in cases when several references are cited the latest published information is included. Inconsistent results and conclusions obtained by different authors are highlighted, followed by discussion of the major findings. The searchable database is available as an Excel file, for information about file availability contact the corresponding author.

The quantification of cytochrome P-450 (CYP 3A4) mRNA in the blood of patients with viral liver diseases

OBJECTIVE

We quantified cytochrome P-450 (CYP) 3A4 mRNA in the blood and liver of patients with viral liver diseases to determine whether CYP 3A4 expression is related to disease progression.

DESIGN AND METHODS

Total RNA was extracted from 10 mL of blood from 12 normal volunteers, from 6 patients with acute hepatitis, 17 with chronic hepatitis, 12 with liver cirrhosis, and 16 with hepatocellular carcinoma. Total RNA from 1 mg of liver tissue was extracted simultaneously in 10 patients. CYP 3A4 mRNA was quantified by competitive reverse-transcription polymerase chain reaction and expressed as log copies/microliter.

RESULTS

The CYP 3A4 mRNA titer in blood correlated with that of the liver (r = 0.65, P < 0.05). The CYP 3A4 mRNA titer was 1.6 +/- 0.4 in normal controls, 1.0 +/- 0.5 in acute hepatitis, 0.7 +/- 0.2 in chronic hepatitis, 0.5 +/- 0.2 in liver cirrhosis, 0.5 +/- 0.2 in hepatocellular carcinoma, and decreased with progression of liver disease (P < 0.05).

CONCLUSION

These data suggest that the CYP 3A4 mRNA level in blood relates to progression of liver disease.

Intra-individual variation and sex differences in gene expression of cytochromes P450 in circulating leukocytes

To clarify partly inconsistent results in gene expression of cytochromes P450 (CYP) in the circulation, we undertook a systematic study over a long time period in 19 healthy men and women. CYP specific mRNA for 1A2, 1B1, 2E1 and 3A4 was studied in the leukocytes collected repeatedly on 20 occasions over a 10-week period. Our study revealed a varying pattern of CYP expression over time. CYP3A4 specific mRNA exhibited the largest intra-individual variation with an average coefficient of variation between 40 and 250%. CYP1B1 and CYP2E1 did not vary as much (39-110%). CYP1A2 was sporadically detected in only ten individuals, but varied considerably when measurable (61-256%). The expression in CYP1B1 was significantly higher in women than in men (P = 0.02). We conclude that CYP gene expression in blood varies considerably over time. It is conceivable that the variation reflects a hitherto unknown influence of exogenous or endogenous factors such as hormones, cytokines, and other circulating factors on the hematogeneous cytochromes.