Effect of aging on cytoskeleton system of Kupffer cell and its phagocytic capacity

AIM: To investigate the age-related alterations of cytoskeleton system in liver Kupffer cell and their relation to the changed phagocytic function. METHODS: The phagocytic function of Kupffer cells from rats of various ages (6 mo, 12 mo,18 mo and 24 mo) were quantitatively evaluated by phagocytosis of polystyrene beads. The actin distribution and measurement of Kupffer cell were determined by a phalloidin-TRITC method; and the myosin and vimentin distribution and measurement with indirect immunochemical staining. RESULTS: Aging resulted in significant alterations of actin, myosin and vimentin distributions and reductions in Kupffer cell; the 3 cytoskeleton components of 24-mo-old Kupffer cell were significantly decreased to 68.0%, 84.9% and 75.5%, respectively of these of 6-mo-old Kupffer cell(P < 0.01,0.01 and 0.01). And these decreases had significant positive relations with the damaged phagocytosis of the aged Kupffer cell. γ values were 0.96(P < 0.05), 0.99(P < 0.01) and 0.95 (P < 0.05) respectively. CONCLUSION: The cytoskeleton system of the aged Kupffer cell presents an evident state of senescence, which may be an important mechanism of decreased phagocytosis of the aged Kupffer cell.