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Postgraduate trainees elevate the academic strength of institutions by conducting research, promoting innovation, securing grant funding, training undergraduate students, and building alliances. Rigorous and systematic program evaluation can help ensure that postgraduate training programs are achieving the program's intended outcomes. The purpose of this project was to develop evidence-based evaluation tools that could be shared across federally funded biomedical training programs to enhance program evaluation capacity. This manuscript describes the evidence-based process used to determine program evaluation needs of these programs at a research-intensive university. Using a multi-phased sequential exploratory mixed methods approach, data were collected from trainees, employers, leaders, and program directors. Data analyses included document analysis of program plans, inductive coding of focus groups and interviews, and descriptive analysis of surveys. Two overarching categories-Trainee Skills and Program Characteristics-were identified including six themes each. Program directors prioritized communication, social and behavioral skills, and collaboration as the trainee skills that they needed the most help evaluating. Furthermore, program directors prioritized the following program characteristics as those that they needed the most help evaluating: training environment, trainee outcomes, and opportunities offered. Surveys, interview scripts, and related resources for the categories and themes were developed and curated on a publicly available website for program directors to use in their program evaluations.

Concerns about the extent to which graduate programs adequately prepare students for the workplace have prompted numerous calls for reform. Understanding what employers look for in doctoral graduates can help schools better align graduate training with workplace needs. Twelve pharmaceutical scientists across diverse specialties and career pathways described the skills considered requisite for success in today's science economy. Depth and breadth of knowledge, communication, collaboration, adaptability, research productivity, experiential training, and motivation and drive were among the themes identified. These results can be used to inform the development of doctoral curricula in the biomedical sciences.

Drug-induced liver injury (DILI) is a leading cause of acute liver failure and transplantation. DILI can be the result of impaired hepatobiliary transporters, with altered bile formation, flow, and subsequent cholestasis. We used gadoxetate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), combined with pharmacokinetic modelling, to measure hepatobiliary transporter function in vivo in rats. The sensitivity and robustness of the method was tested by evaluating the effect of a clinical dose of the antibiotic rifampicin in four different preclinical imaging centers. The mean gadoxetate uptake rate constant for the vehicle groups at all centers was 39.3 +/- 3.4 s-1 (n = 23) and 11.7 +/- 1.3 s-1 (n = 20) for the rifampicin groups. The mean gadoxetate efflux rate constant for the vehicle groups was 1.53 +/- 0.08 s-1 (n = 23) and for the rifampicin treated groups was 0.94 +/- 0.08 s-1 (n = 20). Both the uptake and excretion transporters of gadoxetate were statistically significantly inhibited by the clinical dose of rifampicin at all centers and the size of this treatment group effect was consistent across the centers. Gadoxetate is a clinically approved MRI contrast agent, so this method is readily transferable to the clinic. CONCLUSION:Rate constants of gadoxetate uptake and excretion are sensitive and robust biomarkers to detect early changes in hepatobiliary transporter function in vivo in rats prior to established biomarkers of liver toxicity.

Abstract OATP1B facilitates the uptake of xenobiotics into hepatocytes and is a prominent target for drug–drug interactions (DDIs). Reduced systemic exposure of OATP1B substrates has been reported following multiple‐dose rifampicin; one explanation for this observation is OATP1B induction. Non‐uniform hepatic distribution of OATP1B may impact local rifampicin tissue concentrations and rifampicin‐mediated protein induction, which may affect the accuracy of transporter‐ and/or metabolizing enzyme‐mediated DDI predictions. We incorporated quantitative zonal OATP1B distribution data from immunofluorescence imaging into a PBPK modeling framework to explore rifampicin interactions with OATP1B and CYP substrates. PBPK models were developed for rifampicin, two OATP1B substrates, pravastatin and repaglinide (also metabolized by CYP2C8/CYP3A4), and the CYP3A probe, midazolam. Simulated hepatic uptake of pravastatin and repaglinide increased from the periportal to the pericentral region (approximately 2.1‐fold), consistent with OATP1B distribution data. Simulated rifampicin unbound intracellular concentrations increased in the pericentral region (1.64‐fold) compared to simulations with uniformly distributed OATP1B. The absolute average fold error of the rifampicin PBPK model for predicting substrate maximal concentration (Cmax) and area under the plasma concentration–time curve (AUC) ratios was 1.41 and 1.54, respectively (nine studies). In conclusion, hepatic OATP1B distribution has a considerable impact on simulated zonal substrate uptake clearance values and simulated intracellular perpetrator concentrations, which regulate transporter and metabolic DDIs. Additionally, accounting for rifampicin‐mediated OATP1B induction in parallel with inhibition improved model predictions. This study provides novel insight into the effect of hepatic OATP1B distribution on site‐specific DDI predictions and the impact of accounting for zonal transporter distributions within PBPK models.

Background:. NAFLD is highly prevalent with limited treatment options. Bile acids (BAs) increase in the systemic circulation and liver during NAFLD progression. Changes in plasma membrane localization and zonal distribution of BA transporters can influence transport function and BA homeostasis. However, a thorough characterization of how NAFLD influences these factors is currently lacking. This study aimed to evaluate the impact of NAFLD and the accompanying histologic features on the functional capacity of key hepatocyte BA transporters across zonal regions in human liver biopsies. Methods:. A novel machine learning image classification approach was used to quantify relative zonal abundance and plasma membrane localization of BA transporters (bile salt export pump [BSEP], sodium-taurocholate cotransporting polypeptide, organic anion transporting polypeptides [OATP] 1B1 and OATP1B3) in non-diseased (n = 10), NAFL (n = 9), and NASH (n = 11) liver biopsies. Based on these data, membrane-localized zonal abundance (MZA) measures were developed to estimate transporter functional capacity. Results:. NAFLD diagnosis and histologic scoring were associated with changes in transporter membrane localization and zonation. Increased periportal BSEPMZA (mean proportional difference compared to non-diseased liver of 0.090) and decreased pericentral BSEPMZA (−0.065) were observed with NASH and also in biopsies with higher histologic scores. Compared to Non-diseased Liver, periportal OATP1B3MZA was increased in NAFL (0.041) and NASH (0.047). Grade 2 steatosis (mean proportional difference of 0.043 when compared to grade 0) and grade 1 lobular inflammation (0.043) were associated with increased periportal OATP1B3MZA. Conclusions:. These findings provide novel mechanistic insight into specific transporter alterations that impact BA homeostasis in NAFLD. Changes in BSEPMZA likely contribute to altered BA disposition and pericentral microcholestasis previously reported in some patients with NAFLD. BSEPMZA assessment could inform future development and optimization of NASH-related pharmacotherapies.

Abstract Hepatic cell lines serve as economical and reproducible alternatives for primary human hepatocytes. However, the utility of hepatic cell lines to examine bile acid homeostasis and cholestatic toxicity is limited due to abnormal expression and function of bile acid-metabolizing enzymes, transporters, and the absence of canalicular formation. We discovered that culturing HuH-7 human hepatoma cells with dexamethasone (DEX) and 0.5% dimethyl sulfoxide (DMSO) for two weeks, with Matrigel overlay after one week, resulted in a shorter and improved differentiation process. These culture conditions increased the expression and function of the major bile acid uptake and efflux transporters, sodium taurocholate co-transporting polypeptide (NTCP) and the bile salt export pump (BSEP), respectively, in two-week cultures of HuH-7 cells. This in vitro model was further characterized for expression and function of bile acid-metabolizing enzymes, transporters, and cellular bile acids. Differentiated HuH-7 cells displayed a marked shift in bile acid composition and induction of cytochrome P450 (CYP) 7A1, CYP8B1, CYP3A4, and bile acid-CoA: amino acid N-acyltransferase (BAAT) mRNAs compared to control. Inhibition of taurocholate uptake and excretion after a 24-h treatment with prototypical cholestatic drugs suggests that differentiated HuH-7 cells are a suitable model to examine cholestatic hepatotoxicity.

The sodium taurocholate cotransporting polypeptide (NTCP; gene name SLC10A1) is the primary hepatic basolateral uptake transporter for conjugated bile acids and the entry receptor for the hepatitis B and D virus (HBV/HDV). Regulation of human NTCP remains a knowledge gap due to significant species differences in substrate and inhibitor selectivity and plasma membrane expression. In the present study, various kinase inhibitors were screened for inhibition of NTCP function and taurocholate (TCA) uptake using NTCP-transfected HuH-7 cells. This study identified everolimus, an mTOR inhibitor and macrocyclic immunosuppressive drug, as an NTCP inhibitor with modest potency (IC50 = 6.7–8.0 µM). Further investigation in differentiated HuH-7 cells expressing NTCP and NTCP-overexpressing Flp-In T-REx 293 cells revealed that the mechanism of action of everolimus on NTCP is direct inhibition and mTOR-independent. Structural analogs of everolimus inhibited NTCP-mediated TCA uptake, however, functional analogs did not affect NTCP-mediated TCA transport, providing further evidence for direct inhibition. This work contributes to the growing body of literature suggesting that NTCP-mediated bile acid uptake may be inhibited by macrocyclic peptides, which may be further exploited to develop novel medications against HBV/HDV.

Postgraduate trainees elevate the academic strength of institutions by conducting research, promoting innovation, securing grant funding, training undergraduate students, and building alliances. Rigorous and systematic program evaluation can help ensure that postgraduate training programs are achieving the program’s intended outcomes. The purpose of this project was to develop evidence-based evaluation tools that could be shared across federally funded biomedical training programs to enhance program evaluation capacity. This manuscript describes the evidence-based process used to determine program evaluation needs of these programs at a research-intensive university. Using a multi-phased sequential exploratory mixed methods approach, data were collected from trainees, employers, leaders, and program directors. Data analyses included document analysis of program plans, inductive coding of focus groups and interviews, and descriptive analysis of surveys. Two overarching categories–Trainee Skills and Program Characteristics—were identified including six themes each. Program directors prioritized communication, social and behavioral skills, and collaboration as the trainee skills that they needed the most help evaluating. Furthermore, program directors prioritized the following program characteristics as those that they needed the most help evaluating: training environment, trainee outcomes, and opportunities offered. Surveys, interview scripts, and related resources for the categories and themes were developed and curated on a publicly available website for program directors to use in their program evaluations.

Pregnancy-related hormones (PRH) are recognized as important regulators of hepatic cytochrome P450 enzyme expression and function. However, the impact of PRH on the hepatic expression and function of uridine diphosphate glucuronosyltransferases (UGTs) remains unclear. Using primary human hepatocytes, we evaluated the effect of PRH exposure on mRNA levels and protein concentrations of UGT1A1, UGT2B7, and other key UGT enzymes, and on the metabolism of labetalol (a UGT1A1 and UGT2B7 substrate commonly prescribed to treat hypertensive disorders of pregnancy). Sandwich-cultured human hepatocytes (SCHH) from female donors were exposed to the PRH estradiol, estriol, estetrol, progesterone, and cortisol individually or in combination. We quantified protein concentrations of UGT1A1, UGT2B7, and four additional UGT1A isoforms in SCHH membrane fractions and evaluated the metabolism of labetalol to its glucuronide metabolites in SCHH. PRH exposure increased mRNA levels and protein concentrations of UGT1A1 and UGT1A4 in SCHH. PRH exposure also significantly increased labetalol metabolism to its UGT1A1-derived glucuronide metabolite in a concentration-dependent manner, which positively correlated with PRH-induced changes in UGT1A1 protein concentrations. In contrast, PRH did not alter UGT2B7 mRNA levels or protein concentrations in SCHH, and formation of the UGT2B7-derived labetalol glucuronide metabolite was decreased following PRH exposure. Our findings demonstrate that PRH alter expression and function of UGT proteins in an isoform-specific manner and increase UGT1A1-mediated labetalol metabolism in human hepatocytes by inducing UGT1A1 protein concentrations. These results provide mechanistic insight into the increases in labetalol clearance observed in pregnant individuals.