Hepatoprotective effect of silymarin during negative energy balance in sheep

Silymarin has been used extensively to treat human liver diseases. Its beneficial effect has been proven in periparturient dairy cows. The aim of this study was to investigate the effect of silymarin on compromised liver where negative energy balance primes a series of metabolic disorders. Sixteen male Iranian sheep were divided into four equal groups: control, control plus silymarin, feed-restricted, and feed-restricted plus silymarin. Feed-restricted groups received one third of the daily energy of the control groups. Blood samples were collected four times weekly and analyzed for cholesterol, very-low-density lipoprotein, high-density lipoprotein and low-density lipoprotein cholesterol, triglyceride, aspartate aminotransferase, alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma glutamyl transpeptidase (GGT). Among all the parameters investigated, only GGT values were significantly different between the groups. The interaction of time interval and groups were only significant for ALP and GGT parameters. Animals in the control plus silymarin and feed-restricted groups showed a higher level of GGT. The chemical analysis did not provide any evidence for toxic effects in sheep as demonstrated from our results in the silymarin-treated groups when compared with the non-treated groups. In conclusion, silymarin treatment in the sheep had no effect on clinical chemistry analyses related to energy balance and had no toxic effect on hepatic parenchyma at the administered dosage.