Background & aims

While abstinence-promoting behavioral and pharmacotherapies are part of the therapeutic foundation for alcohol use disorder (AUD) and alcohol-associated liver disease (ALD), these therapies, along with alcohol screening and education, are often underutilized. Our aim was to examine provider attitudes and practices for alcohol screening, treatment and education in patients with liver disease.

Methods

We conducted a survey of primarily (89%) hepatology and gastroenterology providers within (80%) and outside the United States (20%). Surveys were sent to 921 providers with 408 complete responses (44%), of whom 343 (80%) work in a tertiary liver transplant center.

Results

While alcohol screening rates in liver disease patients was nearly universal, less than half of providers reported practicing with integrated addiction providers, using alcohol biomarkers and screening tools. Safe alcohol use by liver disease patients was felt to exist by 40% of providers. While 60% of providers reported referring AUD patients for behavioral therapy, 71% never prescribed AUD pharmacotherapy due to low comfort (84%). Most providers (77%) reported low addiction education and 90% desired more during GI/hepatology fellowship training. Amongst prescribers, baclofen was preferred, but with gaps in pharmacotherapy knowledge. Overall, there was low adherence to the 2019 AASLD practice guidance for ALD, although higher in hepatologists and experienced providers.

Conclusions

While our survey of hepatology and gastroenterology providers demonstrated higher rates of alcohol screening and referrals for behavioral therapy, we found low rates of prescribing AUD pharmacotherapy due to knowledge gaps from insufficient education. Further studies are needed to assess interventions to improve provider alignment with best practices for treating patients with AUD and ALD.

The scaffold protein synectin plays a critical role in the trafficking and regulation of membrane receptor pathways. As platelet-derived growth factor receptor (PDGFR) is essential for hepatic stellate cell (HSC) activation and liver fibrosis, we sought to determine the role of synectin on the PDGFR pathway and development of liver fibrosis. Mice with deletion of synectin from HSC were found to be protected from liver fibrosis. mRNA sequencing revealed that knockdown of synectin in HSC demonstrated reductions in the fibrosis pathway of genes, including PDGFR-β. Chromatin IP assay of the PDGFR-β promoter upon synectin knockdown revealed a pattern of histone marks associated with decreased transcription, dependent on p300 histone acetyltransferase. Synectin knockdown was found to downregulate PDGFR-α protein levels, as well, but through an alternative mechanism: protection from autophagic degradation. Site-directed mutagenesis revealed that ubiquitination of specific PDGFR-α lysine residues was responsible for its autophagic degradation. Furthermore, functional studies showed decreased PDGF-dependent migration and proliferation of HSC after synectin knockdown. Finally, human cirrhotic livers demonstrated increased synectin protein levels. This work provides insight into differential transcriptional and posttranslational mechanisms of synectin regulation of PDGFRs, which are critical to fibrogenesis.