Activation of Insulin-PI3K/Akt-p70S6K Pathway in Hepatic Stellate Cells Contributes to Fibrosis in Nonalcoholic Steatohepatitis.

BACKGROUND AND AIMS: Hyperinsulinemia and insulin resistance are hallmark features of nonalcoholic fatty liver disease and steatohepatitis (NASH). It remains unclear whether and how insulin contributes to the development of fibrosis in NASH. In this study, we explored insulin signaling in the regulation of hepatic stellate cell (HSC) activation and the progression of NASH-fibrosis. METHODS: Phosphorylation of Akt and p70S6K were examined in primary HSC and in a rat model of NASH-fibrosis induced by high-fat and high-cholesterol diet for 24 weeks. HSC activation was analyzed for the changes in cell morphology, intracellular lipid droplets, expression of α-SMA and cell proliferation. The serum markers and histology for NASH-fibrosis were also characterized in animals. RESULTS: Insulin enhanced the expression of smooth muscle actin-α in quiescent but not in activated HSC in culture. Insulin-mediated activation of the PI3K/Akt-p70S6K pathway was involved in the regulation of profibrogenic effects of insulin. Although insulin did not stimulate HSC proliferation directly, the insulin-PI3K/Akt-p70S6K pathway was necessary for serum-enhanced cell proliferation during initial HSC activation. In a rat model of NASH-fibrosis induced by high-fat and high-cholesterol diet, hyperinsulinemia is associated with the activation of p70S6K and enhanced fibrosis. CONCLUSION: The insulin-PI3K/Akt-p70S6K pathway plays an important role in the early activation of HSC. The profibrogenic effect of insulin is dependent on the activation stage of HSC. Dysregulation of the insulin pathway likely correlates with the development of fibrosis in NASH, suggesting a potentially novel antifibrotic target of inhibiting insulin signaling in HSC.

Outcomes Comparison of the Veterans' Choice Program With the Veterans Affairs Health Care System for Hepatitis C Treatment.

BACKGROUND: The US Department of Veterans Affairs (VA) has been stressed by the large number of veterans requiring direct-acting antiviral (DAA) medications for hepatitis C virus (HCV) treatment. The Veterans Choice Program provides VA patients more options to receive treatment. This study compared the experience of veterans who received HCV treatment through the Veterans Choice Program and those that received treatment at the VA Loma Linda Healthcare System (VALLHCS) in fiscal year (FY) 2016. METHODS: A chart review was performed on all veterans referred by VALLHCS to Choice for HCV treatment during FY 2016, and matched to veterans who received treatment at VALLHCS. Data collected included Fibrosis-4 score (Fib-4), platelet count, days elapsed between time of referral and time of appointment (wait time), rate of sustained virologic response at 12 weeks (SVR12), reason for treatment failure, and cost effectiveness. RESULTS: One hundred veterans were referred to Choice; 71 were seen at least once by a Choice provider, and 61 completed a treatment course. Mean Fib-4 and platelet count was 1.9 and 228,000 for the Choice population and 3.4 and 158,000 for the VALLHCS population, respectively. There was no difference in SVR12 rate. Mean wait time was 42 days for Choice vs 29 days for VALLHCS (P < .001). Choice health care providers incurred a mean $8,561.40 in additional costs per veteran seen. CONCLUSIONS: While treatment success rates were similar between Choice and VALLHCS, the degree of liver fibrosis was more advanced in the VALLHCS population. The wait time for care was longer with Choice compared with a direct referral within the VA. While Choice offers a potential solution to providing care for veterans, the current program has unique problems that must be considered.