Bitter orange extract shows promise as a protector against liver damage

In a study published by the Asian Pacific Journal of Tropical Medicine, mice were given doses of Citrus aurantium extract (CAE) to see if could help reduce the effect of bile duct ligation (BDL)-induced liver fibrosis, with promising results.

The researchers, from Korea, noted that Citrus aurantium, which is native to South East Asia and commonly used as a pickle in Indian cooking, has abundant polymethoxy flavones, including nobiletin.

Their previous studies have found that CAE containing approximately 27% of nobiletin had protective effects on binge drinking and carbon tetrachloride intoxication in mice.

However, they added it was unknown if CAE could help prevent cholestasic liver fibrosis, caused when bile cannot flow from the liver to the duodenum.

The study worked on five groups of mice, with the first three composed of a control group of sham-operated mice; mice with liver injury caused by BDL; and BDL mice treated with Silymarin (200 mg) for four weeks. The last two groups were composed of BDL mice given CAE in different doses. The first group was treated with 50mg of CAE for four weeks, the second with 200mg of CAE, also for four weeks.

“We investigated the potential protective effects of CAE (containing approximately 27% of nobiletin) against liver injury induced by obstructive cholestasis in BDL administrated mice,”​ they wrote.

“Bile duct ligation in rodents has been well established…[and] can induce high yields of stereotypical cirrhosis, fibrogenesis, and cholestasis with morphological and biochemical changes of liver and serum comparable to human hypercholesterolemia.”​

Marked reduction

The findings revealed that BDL mice has higher levels of liver injury compared to the control group, as expected. But after four weeks the mice which were given the CAE (50 and 200mg groups) showed decreased hepatocellular injury compared to the group given the Silymarin treatment, and the BDL mice that were not given anything at all.

“Enhanced oxidative status is associated with liver fibrosis”​, wrote the researchers. Results showed that the oxidative status of the livers in BDL-induced group given CAE revealed marked reduction compared to those in the control group.

The levels of apoptasis, or cell deaths, after treatment with CAE  also decreased in the BDL mice (50 and 200 mg groups).

The researchers concluded: “This study showed that nobiletin-rich extract CAE could protect the liver against inflammation, cholestasis, and apoptosis induced by BDL stimulating antioxidant and anti-apoptotic mechanisms in mice.”​

Source: Asian Pacific Journal of Tropical Medicine​

DOI: 10.1016/j.aptjm.2016.10.009​

“Protective effects of a polymethoxy flavonoids-rich Citrus aurantium peel extract on liver fibrosis-induced by bile duct ligation in mice”​

Authors: Seol-Wa Lim, Dong-Ryung Lee, et al​