Evaluating the Utility of Canine Mdr1 Knockout Madin-Darby Canine Kidney I Cells in Permeability Screening and Efflux Substrate Determination.

Permeability assays are commonly conducted with Madin-Darby canine kidney (MDCK) cells to predict the intestinal absorption of small-molecule drug candidates. In addition, MDCK cells transfected to overexpress efflux transporters are often used to identify substrates. However, MDCK cells exhibit endogenous efflux activity for a significant proportion of experimental compounds, potentially leading to the underestimation of permeability and confounded findings in transport studies. The goal of this study was to evaluate canine Mdr1 knockout MDCK (gMDCKI) cells in permeability screening and human MDR1 substrate determination in a drug discovery setting. The gMDCKI cells were established by CRISPR-Cas9-mediated knockout of the canine Mdr1 gene in MDCKI wildtype (wt) cells. A comparison of efflux ratios (ER) between MDCKI wt and gMDCKI showed that out of 135 compounds tested, 38% showed efflux activity in MDCKI wt, while no significant efflux was observed in gMDCKI cells. Apparent permeability (Papp) from apical-to-basolateral (A-to-B) and basolateral-to-apical were near unity in gMDCKI cells, which approximated passive permeability, and 17% of compounds demonstrated increases in their Papp A-to-B values. Overexpression of human MDR1 in gMDCKI (gMDCKI-MDR1) cells enabled substrate determination without the contribution of endogenous efflux, and the assay was able to deconvolute ambiguous results from MDCKI-MDR1 and identify species differences in substrate specificity. An analysis of 395 and 474 compounds in gMDCKI and gMDCKI-MDR1, respectively, suggested physicochemical properties that were associated with low permeability correlated with MDR1 recognition. Poorly permeable compounds and MDR1 substrates were more likely to be large, flexible, and more capable of forming external hydrogen bonds. On the basis of our evaluation, we concluded that gMDCKI is a better cell line for permeability screening and efflux substrate determination than the MDCK wt cell line.

Efficacy of Virtual Care for Depressive Disorders: Systematic Review and Meta-analysis.

BACKGROUND: The COVID-19 pandemic has created an epidemic of distress-related mental disorders such as depression, while simultaneously necessitating a shift to virtual domains of mental health care; yet, the evidence to support the use of virtual interventions is unclear. OBJECTIVE: The purpose of this study was to evaluate the efficacy of virtual interventions for depressive disorders by addressing three key questions: (1) Does virtual intervention provide better outcomes than no treatment or other control conditions (ie, waitlist, treatment as usual [TAU], or attention control)? (2) Does in-person intervention provide better outcomes than virtual intervention? (3) Does one type of virtual intervention provide better outcomes than another? METHODS: We searched the PubMed, EMBASE, and PsycINFO databases for trials published from January 1, 2010, to October 30, 2021. We included randomized controlled trials of adults with depressive disorders that tested a virtual intervention and used a validated depression measure. Primary outcomes were defined as remission (ie, no longer meeting the clinical cutoff for depression), response (ie, a clinically significant reduction in depressive symptoms), and depression severity at posttreatment. Two researchers independently selected studies and extracted data using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Risk of bias was evaluated based on Agency for Healthcare and Research Quality guidelines. We calculated odds ratios (ORs) for binary outcomes and standardized mean differences (SMDs) for continuous outcomes. RESULTS: We identified 3797 references, 24 of which were eligible. Compared with waitlist, virtual intervention had higher odds of remission (OR 10.30, 95% CI 5.70-18.60; N=619 patients) and lower posttreatment symptom severity (SMD 0.81, 95% CI 0.52-1.10; N=1071). Compared with TAU and virtual attention control conditions, virtual intervention had higher odds of remission (OR 2.27, 95% CI 1.10-3.35; N=512) and lower posttreatment symptom severity (SMD 0.25, 95% CI 0.09-0.42; N=573). In-person intervention outcomes were not significantly different from virtual intervention outcomes (eg, remission OR 0.84, CI 0.51-1.37; N=789). No eligible studies directly compared one active virtual intervention to another. CONCLUSIONS: Virtual interventions were efficacious compared with control conditions, including waitlist control, TAU, and attention control. Although the number of studies was relatively small, the strength of evidence was moderate that in-person interventions did not yield significantly better outcomes than virtual interventions for depressive disorders.