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NASH will soon become the leading cause of liver transplantation in the United States and is also associated with increased COVID-19 mortality. Currently, there are no Food and Drug Administration-approved drugs available that slow NASH progression or address NASH liver involvement in COVID-19. Because animal models cannot fully recapitulate human NASH, we hypothesized that stem cells isolated directly from end-stage liver from patients with NASH may address current knowledge gaps in human NASH pathology.We devised methods that allow the derivation, proliferation, hepatic differentiation, and extensive characterization of bipotent ductal organoids from irreversibly damaged liver from patients with NASH. The transcriptomes of organoids derived from NASH liver, but not healthy liver, show significant up-regulation of proinflammatory and cytochrome p450-related pathways, as well as of known liver fibrosis and tumor markers, with the degree of up-regulation being patient-specific. Functionally, NASH liver organoids exhibit reduced passaging/growth capacity and hallmarks of NASH liver, including decreased albumin production, increased free fatty acid-induced lipid accumulation, increased sensitivity to apoptotic stimuli, and increased cytochrome P450 metabolism. After hepatic differentiation, NASH liver organoids exhibit reduced ability to dedifferentiate back to the biliary state, consistent with the known reduced regenerative ability of NASH livers. Intriguingly, NASH liver organoids also show strongly increased permissiveness to severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vesicular stomatitis pseudovirus as well as up-regulation of ubiquitin D, a known inhibitor of the antiviral interferon host response.Expansion of primary liver stem cells/organoids derived directly from irreversibly damaged liver from patients with NASH opens up experimental avenues for personalized disease modeling and drug development that has the potential to slow human NASH progression and to counteract NASH-related SARS-CoV-2 effects.

Objective Higher levels of optimism have been linked with positive health behaviors, biological processes, and health conditions that are potentially protective against cognitive impairment in older adults. However, the association between optimism and cognitive impairment has not been directly investigated. We examined whether optimism is associated with incident cognitive impairment in older adults. Methods Data are from the Health and Retirement Study. Optimism was measured by using the Life Orientation Test-R and cognitive impairment with a modified version of the Telephone Interview for Cognitive Status derived from the Mini-Mental State Examination. Using multiple logistic regression models, we prospectively assessed whether optimism was associated with incident cognitive impairment in 4624 adults 65 years and older during a 4-year period. Results Among participants, 312 women and 190 men developed cognitive impairment during the 4-year follow-up. Higher optimism was associated with decreased risk of incident cognitive impairment. When adjusted for sociodemographic factors, each standard deviation increase in optimism was associated with reduced odds (odds ratio [OR] = 0.70, 95% confidence interval [CI] = 0.61-0.81) of becoming cognitively impaired. A dose-response relationship was observed. Compared with those with the lowest levels of optimism, people with moderate levels had somewhat reduced odds of cognitive impairment (OR = 0.78, 95% CI = 0.59-1.03), whereas people with the highest levels had the lowest odds of cognitive impairment (OR = 0.52, 95% CI = 0.36-0.74). These associations remained after adjusting for health behaviors, biological factors, and psychological covariates that could either confound the association of interest or serve on the pathway. Conclusions Optimism was prospectively associated with a reduced likelihood of becoming cognitively impaired. If these results are replicated, the data suggest that potentially modifiable aspects of positive psychological functioning such as optimism play an important role in maintaining cognitive functioning.