Aging is associated with marked changes in the hepatic sinusoid, yet the effect of old age on hepatic stellate cells (HSC) has not been well described.

The aim of a study published in Current Gerontology and Geriatrics Research was to assess the effects of aging on hepatic stellate cells (HSC) in the liver.

In this study, transmission electron microscopy and immunohistochemistry were used in livers from rats – 3-4 months versus 24-27 months; and mice – 2-3 months versus 20-22 months.

The results showed that Desmin-positive HSC doubled in old age, in both, mice and rats. Meanwhile, alpha-smooth muscle actin- (αSMA-) positive cells did not increase significantly, and remained only a small percentage of the desmin-positive cells. In addition, there was a marked increase of HSC that protruded into the sinusoidal lumen in old mice. Electron microscopy revealed that old age is associated with HSC that have a substantial increased number of lipid droplets that are larger in diameter.

The results indicated that old age is associated with hyperplasia of HSC that are not activated and are engorged with lipid droplets. This has implications for the effect of age on retinoid metabolism and for the mechanisms for other age-related morphological changes in the hepatic sinusoid. It was speculated that the increase in the percentage and number of enlarged HSCs that resulted in protrusion of the endothelial lining into the sinusoidal lumen in old mice may contribute to the reduced sinusoidal blood flow reported in aged mice.

Source: Current Gerontology and Geriatrics Research. Volume 2011. Article ID 439835. https://doi.org/10.1155/2011/439835