TY - JOUR
T1 - Gender Dimorphic Formation of Mouse Mallory-Denk Bodies and the Role of Xenobiotic Metabolism and Oxidative Stress
AU - Hanada, Shinichiro
AU - Snider, Natasha T.
AU - Brunt, Elizabeth M.
AU - Hollenberg, Paul F.
AU - Omary, M. Bishr
N1 - Funding Information:
Funding This study was supported by a National Institutes of Health grant ( DK52951 ) and by the Department of Veterans Affairs (M.B.O.) and by a University of Michigan Postdoctoral Translational Scholars Program Award ( UL1RR024986 to N.T.S.).
PY - 2010/4
Y1 - 2010/4
N2 - Background & Aims: Mallory-Denk bodies (MDBs) are keratin (K)-rich cytoplasmic hepatocyte inclusions commonly associated with alcoholic steatohepatitis. Given the significant gender differences in predisposition to human alcohol-related liver injury, and the strain difference in mouse MDB formation, we hypothesized that sex affects MDB formation. Methods: MDBs were induced in male and female mice overexpressing K8, which are predisposed to MDB formation, and in nontransgenic mice by feeding the porphyrinogenic compound 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). MDB presence was determined by histologic, immunofluorescence, and biochemical analyses and correlated to liver injury using serologic and pathologic markers. Cytoskeletal and metabolic liver protein analysis, in vitro metabolism studies, and measurement of oxidative stress markers and protoporphyrin-IX were performed. Results: Male mice formed significantly more MDBs, which was attenuated modestly by estradiol. MDB formation was accompanied by increased oxidative stress. Female mice had significantly fewer MDBs and oxidative stress-related changes, but had increased ductular reaction protoporphyrin-IX accumulation, and MDB-preventive K18 induction. Evaluation of the microsomal cytochrome-P450 (CYP) enzymes revealed significant gender differences in protein expression and activity in untreated and DDC-fed mice, and showed that DDC is metabolized by CYP3A. The changes in CYPs account for the gender differences in porphyria and DDC metabolism. DDC metabolite formation and oxidative injury accumulate on chronic DDC exposure in males, despite more efficient acute metabolism in females. Conclusions: Gender dimorphic formation of MDBs and porphyria associate with differences in CYPs, oxidative injury, and selective keratin induction. These findings may extend to human MDBs and other neuropathy- and myopathy-related inclusions.
AB - Background & Aims: Mallory-Denk bodies (MDBs) are keratin (K)-rich cytoplasmic hepatocyte inclusions commonly associated with alcoholic steatohepatitis. Given the significant gender differences in predisposition to human alcohol-related liver injury, and the strain difference in mouse MDB formation, we hypothesized that sex affects MDB formation. Methods: MDBs were induced in male and female mice overexpressing K8, which are predisposed to MDB formation, and in nontransgenic mice by feeding the porphyrinogenic compound 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). MDB presence was determined by histologic, immunofluorescence, and biochemical analyses and correlated to liver injury using serologic and pathologic markers. Cytoskeletal and metabolic liver protein analysis, in vitro metabolism studies, and measurement of oxidative stress markers and protoporphyrin-IX were performed. Results: Male mice formed significantly more MDBs, which was attenuated modestly by estradiol. MDB formation was accompanied by increased oxidative stress. Female mice had significantly fewer MDBs and oxidative stress-related changes, but had increased ductular reaction protoporphyrin-IX accumulation, and MDB-preventive K18 induction. Evaluation of the microsomal cytochrome-P450 (CYP) enzymes revealed significant gender differences in protein expression and activity in untreated and DDC-fed mice, and showed that DDC is metabolized by CYP3A. The changes in CYPs account for the gender differences in porphyria and DDC metabolism. DDC metabolite formation and oxidative injury accumulate on chronic DDC exposure in males, despite more efficient acute metabolism in females. Conclusions: Gender dimorphic formation of MDBs and porphyria associate with differences in CYPs, oxidative injury, and selective keratin induction. These findings may extend to human MDBs and other neuropathy- and myopathy-related inclusions.
KW - Cytochrome P450
KW - Liver inclusions
KW - keratins
UR - http://www.scopus.com/inward/record.url?scp=77949820532&partnerID=8YFLogxK
U2 - 10.1053/j.gastro.2009.12.055
DO - 10.1053/j.gastro.2009.12.055
M3 - Article
C2 - 20064513
AN - SCOPUS:77949820532
SN - 0016-5085
VL - 138
SP - 1607
EP - 1617
JO - Gastroenterology
JF - Gastroenterology
IS - 4
ER -