Aging, acute oxidative injury and hepatocellular glucose transport in the rat

doi:10.1016/0928-4346(94)00186-9

International Hepatology Communications

Volume 3, Issue 5, May 1995, Pages 244-253

https://doi.org/10.1016/0928-4346(94)00186-9 Get rights and content

Abstract

We studied the effects of aging and acute exposure to hydrogen peroxide on hepatocellular glucose transport to determine whether (1) acute oxidative stress impairs glucose transport, (2) aging is associated with reduced glucose transport and (3) there are similarities between these changes that may provide insight into the aging process. Glucose transport was measured in the perfused livers of young and aged rats using the multiple indicator-dilution method. There were significant reductions in the rate constants for glucose influx (P < 0.001) and a significant increase in the extracellular volume in the livers from aged rats (aged: 0.39 ± 0.05 ml/g, young: 0.27 ± 0.04 ml/g). However, the K_m and V_max for glucose influx in the livers from aged rats (44 ± 22 mM, 7.1 ± 1.4 μmol.s⁻¹g⁻¹, respectively) were not significantly different from the values in young rats (64 ± 20 mM, 8.8 ± 1.3 μmol.s⁻¹g⁻¹). In the livers of young rats, treatment with hydrogen peroxide caused a significant reduction in glucose transport from 1.18 ± 0.22 to 0.49 ± 0.25 μmol.s⁻¹g⁻¹. This was partly restored to 0.69 ± 0.20 μmol.s⁻¹g⁻¹ by occluding the outflow catheter and expanding the extracellular space. Thus, although aging did not influence the rate of glucose transport in the perfused rat liver, this may be due to a compensatory age-related increase in the extracellular volume. In conclusion, the changes observed in hepatocellular glucose transport in the aged liver could be simulated by oxidative injury in the young liver, suggesting a role for oxidative injury in the aging process.

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Short communicationAging, acute oxidative injury and hepatocellular glucose transport in the rat

Abstract

Mech Ageing Dev

Mech Ageing Dev

Biochem Pharmacol

Int Rev Cytol

Biochem Pharmacol

Biochem Pharmacol

Free radical involvement in aging. Pathophysiology and therapeutic applications

Drugs Aging

A review of the recent advances in the membrane hypothesis of aging

Age-dependent decrease in the hepatic uptake and biliary excretion of ouabain in rats

Biochem Pharmacol

Short communication
Aging, acute oxidative injury and hepatocellular glucose transport in the rat