Background Polycystic liver disease
(PLD) is a hereditary liver disease with progressive enlargement of fluid-filled liver cysts, which causes abdominal discomfort and worsens quality of life. Long-term exercise
has beneficial effects in various organs, but the effects of long-term exercise
on PLD are unclear. Therefore, the aim of this study was to investigate whether long-term exercise
inhibits liver cyst formation and fibrosis
Polycystic kidney (
PCK) rats, a model of PLD, were randomly divided into a sedentary group and a long-term exercise
group, which underwent treadmill running for 12weeks (28 m/min, 60 min/day, 5 days/week). Sprague-Dawley (SD) rats were set as a control group. After 12 weeks, exercise
capacity, histology and signaling cascades of PLD were examined.
Compared with control SD rats, PCK rats showed a low exercise
capacity before exercise
protocol. After 12 weeks, the exercise
improved the exercise
capacity and ameliorated liver cyst formation and fibrosis
. The exercise
also significantly decreased the number of Ki-67 positive cells, the expression of cystic fibrosis
transmembrane conductance regulator, aquaporin 1, transforming growth factor -β and type 1 collagen and the phosphorylation of extracellular signal-regulated kinase, mammalian target of rapamycin and S6, and increased the phosphorylation of AMP-activated protein kinase in the liver of PCK rats.
The present results indicated that long-term exercise
with a moderate intensity ameliorates liver cyst formation and fibrosis
with the inhibition of signaling cascades responsible for cellular proliferation
in PCK rats.