Effects of Polygonum multiflorum on the activity of cytochrome P450 isoforms in rats.

Polygonum multiflorum is a traditional Chinese medicinal herb used in clinical medicine to nourish the liver and kidney. However, in recent years, there have been increased reports of clinical adverse reactions associated with Polygonum multiflorum preparations, especially due to liver injury. The cocktail method can be used to assess the influence of Polygonum multiflorum on the activity of cytochrome P450 (CYP450) isoforms CYP2B6, CYP2C19, CYP2C9, CYP1A2, CYP3A4, and CYP2D6, which were reflected by changes in pharmacokinetic parameters in six specific probe drugs: bupropion, omeprazole, tolbutamide, phenacetin, midazolam, and metoprolol. Comprised the experimental rats were randomly divided into five groups: control group, alcohol extraction A group, alcohol extraction B group, water extraction A group, and water extraction B group. Each group five male rats and five female rats. Each of the groups received treatments by gavage as follows: control group was given normal saline, alcohol extraction A group was given 15 g/kg alcohol extract of Polygonum multiflorum (E15), alcohol extraction B group was given with 30 g/kg alcohol extract (E30), water extraction A group was given 15 g/kg water extract (W15), and water extraction B group was given 30 g/kg water extract (W30). The extract solution was orally administered once a day for 28 consecutive days. The mixture of six probe drugs was given by gavage, and blood samples were collected through the tail vein at different time points. Probe drug concentration in rat plasma was measured by liquid chromatography-mass spectrometry (LC-MS). In the treatment and control groups, Polygonum multiflorum alcoholic extract inhibited the activity of CYP2C19 and CYP2C9 and induced the activity of CYP1A2. Polygonum multiflorum aquous extract inhibited the activity of CYP2B6, CYP2C19, CYP2C9, CYP1A2, and CYP2D6. Pathological sections showed that in the alcohol extract group the liver was degenerated inconspicuously, and in the water extract group, the cytoplasm had vacuoles and particulate matter. The arrangement of liver cells was irregular.