FROM CMGH
Obeticholic acid failed to prevent the development of short-bowel syndrome–associated liver disease in a preliminary study using piglet models. The findings were published in the July issue of Cellular and Molecular Gastroenterology and Hepatology ( doi: 10.1016/j.jcmgh.2017.02.008 ).
Current treatment options for short-bowel syndrome-associated liver disease are limited, wrote Prue M. Pereira-Fantini, PhD, of Murdoch Childrens Research Institute, Victoria, Australia, and colleagues. However, the farnesoid X receptor, which regulates genes involved in bile acid synthesis, absorption, and transport in the intestine and liver, has shown promise as a pharmaceutical target.
“Recently, we described SBS-ALD-associated alterations in bile acid composition associated with disrupted farnesoid X receptor (FXR) signaling mechanisms,” the researchers said. Obeticholic acid (OCA) has been shown to prevent liver disease in mouse models and human disease, and the researchers explored whether it would be effective in the context of short-bowel syndrome associated liver disease (SBS-ALD).
The researchers randomized piglets into four groups to receive small-bowel resection or sham surgery, and either a daily dose of 2.4 mg/kg per day of OCA or no treatment. The pigs were euthanized 2 weeks after their surgeries, and the researchers collected portal plasma samples, bile samples, and liver samples.
OCA treatment in piglets in the SBS surgery group was associated with decreased stool fat that suggested improved fat absorption, but impacted liver morphology, the researchers noted. “Untreated, sham-operated piglets showed normal liver histology when compared with SBS piglets who showed decreased hepatic lobule area and small clusters of inflammatory cells together with mild-to-moderate vesicular zone 2 lipidosis,” they wrote.
Overall, OCA treatment prevented the depletion of taurine; taurine concentration was approximately 8 ng/mL for piglets with SBS treated with OCA compared with 8 ng/mL in the sham group, 9 ng/mL in the sham plus OCA group, and 3 ng/mL in the SBS-only group. However, bile acid dysmetabolism occurred as shown by HDCA levels, which increased with OCA treatment compared to sham controls but were significantly reduced in SBS piglets treated with OCA vs. untreated SBS piglets.
In addition, the researchers found that small-bowel resection did not impact gene expression levels of FXR targets in the intestine or liver. However, “intestinal FXR gene expression was 11-fold higher in untreated SBS piglets when compared with untreated sham piglets,” they wrote. OCA treatment had no significant impact on FXR gene expression in the OCA-treated group vs. the untreated group and in the OCA-treated SBS group.
Although the findings were limited by use of an animal model, the results suggest that OCA treatment may have clinical benefits for SBS patients by reducing fat malabsorption, which remains a challenge, the researchers wrote. However, OCA “did not prevent the development of SBS-ALD, thereby limiting the potential therapeutic benefit in patients with SBS,” they concluded.
The researchers had no financial conflicts to disclose. The study was supported in part by the National Health and Medical Research Council of Australia and by a research grant from the Science Foundation Ireland.
