Hepatoprotective Effect of Fresh Grape Juice Prepared by a Low-Speed Masticating Juicer in db/db Mice

This study investigated the hepatoprotective effect of fresh grape juice prepared using a low-speed masticating (LSM) juicer or a high-speed centrifugal (HSC) juicer in mice. Six-week-old db/db mice were fed on an AIN-93G diet or a diet containing 1% freeze-dried LSM or HSC grape juice for 7 weeks. Treatment with LSM grape juice significantly decreased hepatic triglycerides, serum aspartate transaminase activities, and homeostasis model assessment for insulin resistance values, whereas HSC juice did not significantly influence these parameters. The LSM grape juice showed higher antioxidant and anti-inflammatory activities than HSC juice. The benefits of LSM grape juice are probably due to a much higher proanthocyanidin content than that of HSC juice. These results suggest that LSM grape juice can exert hepatoprotective effects in db/db mice, partly through improving insulin resistance and promoting antioxidant and inflammatory activities.