Dysregulation of Amino Acid Transporters in a Rat Model of TLR7-Mediated Maternal Immune Activation.

Maternal immune activation (MIA) during pregnancy is linked to neurodevelopmental disorders in humans. Similarly, the TLR7 agonist imiquimod alters neurodevelopment in rodents. While the mechanisms underlying MIA-mediated neurodevelopmental changes are unknown, they could involve dysregulation of amino acid transporters essential for neurodevelopment. Therefore, we sought to determine the nature of such transporter changes in both imiquimod-treated rats and human placentas during infection. Pregnant rats received imiquimod on gestational day (GD)14. Transporter expression was measured in placentas and fetal brains via qPCR (GD14.5) and immunoblotting (GD16). To monitor function, fetal brain amino acid levels were measured by HPLC on GD16. Gene expression in the cortex of female fetal brains was further examined by RNAseq on GD19. In human placentas, suspected active infection was associated with decreased ASCT1 and SNAT2 protein expression. Similarly, in imiquimod-treated rats, ASCT1 and SNAT2 protein was also decreased in male placentas, while EAAT2 was decreased in female placentas. CAT3 was increased in female fetal brains. Consistent with this, imiquimod altered amino acid levels in fetal brains, while RNAseq demonstrated changes in expression of several genes implicated in autism. Thus, imiquimod alters amino acid transporter levels in pregnant rats, and similar changes occur in human placentas during active infection. This suggests that changes in expression of amino acid transporters may contribute to effects mediated by MIA toward altered neurodevelopment.

Use of Traditional and Proteomic Methods in the Assessment of a Preclinical Model of Preeclampsia.

Recent studies have demonstrated downregulation of breast cancer resistance protein (BCRP/ABCG2) in placenta obtained from women with preeclampsia (PE). BCRP is highly expressed in placenta and plays an important role in preventing xenobiotics from entering the fetal compartment. Although PE is often therapeutically managed with drugs that are substrates of BCRP, there are limited studies on the impact of PE on fetal drug exposure. Due to ethical concerns, use of preclinical models is an important approach. Thus, by using proteomic and traditional methods, we characterized transporter changes in an immunologic rat model of PE to determine its utility and predictive value for future drug disposition studies. PE was induced by daily administration of low-dose endotoxin (0.01-0.04 mg/kg) to rats on gestational days (GD) 13-16, urine was collected, and rats were sacrificed on GD17 or GD18. PE rats shared similar phenotype to PE patients, including proteinuria, and increased levels of tumor necrosis factor α and interleukin 6. Transcript and protein levels of Bcrp were significantly downregulated in placenta of PE rats on GD18. multidrug resistance 1a, multidrug resistance 1b, and organic anion transporting polypeptide 2B1 mRNA were also decreased in PE. Proteomics revealed activation of various hallmarks of PE including immune activation, oxidative stress, endoplasmic reticulum stress and apoptosis. Overall, our results demonstrated that the immunologic PE rat model exhibits numerous similarities to human PE along with dysregulation of placental transporters. Therefore, this model may be useful in examining the impact of PE on the maternal and fetal disposition of BCRP substrates. SIGNIFICANCE STATEMENT: Fully characterizing preclinical models of disease is necessary to determine their validity to human conditions. Combining traditional and proteomic methods of model characterization, we identified numerous phenotypic similarities between our model of preeclampsia and human disease. The alignment with human pathophysiological changes allows for more confident use of this preclinical model.

COVID-19 Vaccines and the Virus: Impact on Drug Metabolism and Pharmacokinetics.

This article reports on an American Society of Pharmacology and Therapeutics, Division of Drug Metabolism and Disposition symposium held at Experimental Biology on April 2, 2022, in Philadelphia. As of July 2022, over 500 million people have been infected with SARS-CoV-2 (the virus causing COVID-19) and over 12 billion vaccine doses have been administered. Clinically significant interactions between viral infections and hepatic drug metabolism were first recognized over 40 years ago during a cluster of pediatric theophylline toxicity cases attributed to reduced hepatic drug metabolism amid an influenza B outbreak. Today, a substantive body of research supports that the activated innate immune response generally decreases hepatic cytochrome P450 activity. The interactions extend to drug transporters and other organs and have the potential to impact drug absorption, distribution, metabolism, and excretion (ADME). Based on this knowledge, altered ADME is predicted with SARS-CoV-2 infection or vaccination. The report begins with a clinical case exploring the possibility of SARS-CoV-2 vaccination increasing clozapine levels. This is followed by discussions of how SARS-CoV-2 infection or vaccines alter the metabolism and disposition of complex drugs, such as nanoparticles and biologics and small molecule therapies. The review concludes with a discussion of the effects of viral infections on placental amino acid transport and their potential to impact fetal development. The session improved our understanding of the impact of emerging viral infections and vaccine technologies on drug metabolism and disposition, which will help mitigate drug toxicity and improve drug and vaccine safety and effectiveness. SIGNIFICANCE STATEMENT: Altered pharmacokinetics of small molecule and complex molecule drugs and fetal brain distribution of amino acids following SARS-CoV-2 infection or immunization are possible. The proposed mechanisms involve decreased liver cytochrome P450 metabolism of small molecules, enhanced innate immune system metabolism of complex molecules, and altered placental and fetal blood-brain barrier amino acid transport, respectively. Future research is needed to understand the effects of these interactions on adverse drug responses, drug and vaccine safety, and effectiveness and fetal neurodevelopment.

The Effect of Tobacco Use on the Expression of Placental Transporters in Alaska Native Women.

Prenatal tobacco use among Alaska Native (AN) women has decreased substantially over the past two decades. Previous research suggests that providing AN women with feedback regarding fetal exposure to tobacco may further promote cessation. Transporters in the placenta regulate fetal exposure to nutrients and xenobiotics, including compounds associated with tobacco use. We examined whether prenatal tobacco use impacts transporter expression in the placenta, and whether this is influenced by fetal sex, degree of tobacco exposure, or transporter genotype. At delivery, we obtained placental samples from AN research participants who smoked cigarettes, used commercial chew or iqmik (oral tobacco), or did not use tobacco during pregnancy. Transporter expression was evaluated using qRT-PCR and Western blotting and tested for correlations between transcript levels and urinary biomarkers of tobacco use. The impact of BCRP/ABCG2 and OATP2B1/SLCO2B1 genotypes on protein expression was also examined. Oral tobacco use was associated with decreased P-gp and increased MRP1, MRP3, LAT1, and PMAT mRNA expression. Transcript levels of multiple transporters significantly correlated with tobacco biomarkers in maternal and fetal urine. In women carrying male fetuses, both smoking and oral tobacco were associated with decreased P-gp. Oral tobacco was also associated with decreased LAT1 in women carrying female fetuses. BCRP and OATP2B1 genotypes did not appear to impact protein expression. In conclusion, prenatal tobacco use is associated with altered expression of multiple placental transporters which differs by fetal sex. As transcript levels of multiple transporters were significantly correlated with tobacco use biomarkers, eliminating prenatal tobacco use should alleviate these changes.

Transporter Regulation in Critical Protective Barriers: Focus on Brain and Placenta.

Drug transporters play an important role in the maintenance of chemical balance and homeostasis in different tissues. In addition to their physiological functions, they are crucial for the absorption, distribution, and elimination of many clinically important drugs, thereby impacting therapeutic efficacy and toxicity. Increasing evidence has demonstrated that infectious, metabolic, inflammatory, and neurodegenerative diseases alter the expression and function of drug transporters. However, the current knowledge on transporter regulation in critical protective barriers, such as the brain and placenta, is still limited and requires more research. For instance, while many studies have examined P-glycoprotein, it is evident that research on the regulation of highly expressed transporters in the blood-brain barrier and blood-placental barrier are lacking. The aim of this review is to summarize the currently available literature in order to better understand transporter regulation in these critical barriers.

Impact of inflammation and infection on the expression of amino acid transporters in the placenta: A minireview.

Amino acid transporters expressed in the placenta help to regulate the transfer of amino acids from maternal to fetal circulation. Nutritional or hormonal factors are known to potentially impact the expression of amino acid transporters in the placenta. A relatively new field of inquiry has also demonstrated that inflammation, whether associated with infection or not, also alters the expression of amino acid transporters in the placenta. Indeed, studies over the past 15 years have demonstrated that malaria, viral and bacterial models of infection, preeclampsia, and direct administration of proinflammatory cytokines can alter placental amino acid transporter expression. While such studies have largely focused on System A and System L transporters, other transporters are also affected. p38 MAPK, STAT3, mTORC1, and AMPK signaling have all been implicated in these changes, but the underlying mechanism(s) remain to be fully elucidated. Furthermore, the implications of such changes warrant further investigation. This review will summarize studies that have investigated the impact of inflammation on placental amino acid transporter expression, identify questions that remain unanswered, and propose future areas of research to advance the field. As amino acid transporters are now being considered for drug targeting and drug delivery, furthering our understanding of the regulation of these transporters during disease states will be of increasing clinical value. Significance Statement While this is a relatively new field of research, multiple studies have demonstrated that inflammation alters placental amino acid transporter expression. This review will serve to summarize, for the first time, studies in this field and identify gaps in current knowledge as research in this area moves beyond identifying changes in transporter expression to investigating the implications of such changes and the mechanisms underlying them.

Regulation of Drug Transport Proteins-From Mechanisms to Clinical Impact: A White Paper on Behalf of the International Transporter Consortium.

Membrane transport proteins are involved in the absorption, disposition, efficacy, and/or toxicity of many drugs. Numerous mechanisms (e.g., nuclear receptors, epigenetic gene regulation, microRNAs, alternative splicing, post-translational modifications, and trafficking) regulate transport protein levels, localization, and function. Various factors associated with disease, medications, and dietary constituents, for example, may alter the regulation and activity of transport proteins in the intestine, liver, kidneys, brain, lungs, placenta, and other important sites, such as tumor tissue. This white paper reviews key mechanisms and regulatory factors that alter the function of clinically relevant transport proteins involved in drug disposition. Current considerations with in vitro and in vivo models that are used to investigate transporter regulation are discussed, including strengths, limitations, and the inherent challenges in predicting the impact of changes due to regulation of one transporter on compensatory pathways and overall drug disposition. In addition, translation and scaling of in vitro observations to in vivo outcomes are considered. The importance of incorporating altered transporter regulation in modeling and simulation approaches to predict the clinical impact on drug disposition is also discussed. Regulation of transporters is highly complex and, therefore, identification of knowledge gaps will aid in directing future research to expand our understanding of clinically relevant molecular mechanisms of transporter regulation. This information is critical to the development of tools and approaches to improve therapeutic outcomes by predicting more accurately the impact of regulation-mediated changes in transporter function on drug disposition and response.

Pharmacists as Personalized Medicine Experts (PRIME): Experiences Implementing Pharmacist-Led Pharmacogenomic Testing in Primary Care Practices.

Research exploring the integration of pharmacogenomics (PGx) testing by pharmacists into their primary care practices (including community pharmacies) has focused on the "external" factors that impact practice implementation. In this study, additional "internal" factors, related to the capabilities, opportunities, and motivations of pharmacists that influence their ability to implement PGx testing, were analyzed. Semi-structured interview data from the Pharmacists as Personalized Medicine Experts (PRIME) study, which examined the barriers and facilitators to implementing PGx testing by pharmacists into primary care practice, were analyzed. Through thematic analysis, using the theoretical domains framework (TDF) domains as deductive codes, the authors identified the most relevant TDF domains and applied the behavioural change wheel (BCW) to generate intervention types to aid in the implementation of PGx testing. Pharmacists described how their professional identities, practice environments, self-confidence, and beliefs in the benefits of PGx impacted their ability to provide a PGx-testing service. Potential interventions to improve the implementation of the PGx service included preparing pharmacists for managing an increased patient load, helping pharmacists navigate the software and technology requirements associated with the PGx service, and streamlining workflows and documentation requirements. As interest in the wide-scale implementation of PGx testing through community pharmacies grows, additional strategies need to address the "internal" factors that influence the ability of pharmacists to integrate testing into their practices.

Viral model of maternal immune activation alters placental AMPK and mTORC1 signaling in rats.

INTRODUCTION: Maternal immune activation (MIA) is associated with neurodevelopmental disorders in offspring. We previously demonstrated that poly(I:C)-mediated MIA alters placental and fetal brain amino acid transporter expression in rats, which could potentially play a role in altered neurodevelopment; however, the mechanism(s) underlying these changes in amino acid transporter expression remain unknown. The objective of the current study was to investigate the mechanism(s) underlying poly(I:C)-mediated changes in the expression of the amino acid transporters in the placenta. METHODS: Pregnant rats received poly(I:C) on gestational day 14 and placentas were collected 6 h later. Mass spectrometry-based proteomics of placentas was performed followed by pathway enrichment analysis. Activation of mTORC1 and its upstream regulator, AMPK, was investigated using immunoblotting. Finally, the role of mTORC1 and AMPK in regulating the expression and localization of the amino acid transporters EAAT2 and ASCT1 was investigated in the human choriocarcinoma cell line JAR. RESULTS: The impact of poly(I:C) on the placental proteome was highly sexually dimorphic. While proteomics-based pathway enrichment analysis indicated enrichment of mTOR signaling in male placentas only, further investigation revealed inhibition of mTORC1 in both male and female placentas in addition to activation of AMPK. In vitro, activation of AMPK and inhibition of mTORC1 decreased membrane localization of EAAT2 and ASCT1. DISCUSSION: Poly(I:C)-mediated MIA activates AMPK and inhibits mTORC1 in rat placenta, both of which decrease expression and membrane localization of EAAT2 and ASCT1 in vitro. Thus, AMPK/mTORC1 signaling could be a novel treatment target for alleviating MIA-mediated changes in placental amino acid transport.

Impact of Th-17 Cytokines on the Regulation of Transporters in Human Placental Explants.

Activated T helper 17 (Th-17) cytokines play a role in the pathophysiology of autoimmune and infectious diseases. While these diseases affect many women of childbearing age, little is known about the effect of these cytokines on placental transporters. As several pro-inflammatory cytokines impact the expression of ABC and SLC placental transporters, we hypothesized that these transporters may be similarly altered by elevated levels of circulating Th-17 cytokines. Cultured term human villous explants were treated with IL-17A, IL-22, or IL-23, alone or in combination. Samples were analyzed using qRT-PCR and Western blotting. The mRNA expression of OATP2B1 was significantly downregulated in explants by all individual cytokines and combination treatments, while decreased protein expression was seen with IL-23 and combination (p < 0.01). Combination treatment decreased the mRNA expression of BCRP and OAT4 but increased that of OCT3 (p < 0.01). Decreased accumulation of the OATP substrate, cascade blue, was seen in IL-23-treated choriocarcinoma JAr cells (p < 0.01). Elevated Th-17 cytokines, which are seen in infectious and autoimmune diseases, affect the expression and activity of OATP2B1, as well as mRNA expression of placental BCRP, OAT4, and OCT3. This dysregulation could impact the fetal exposure to endogenous and exogenous substrates.

Role of HIV and Antiretroviral Therapy on the Expression of Placental Transporters in Women with HIV.

Treatment guidelines recommend continuation of combination antiretroviral therapy (cART) throughout pregnancy for all women living with human immunodeficiency virus (HIV). Many of these drugs are substrates of transporters expressed in the placenta and therefore play a role in fetal exposure. As placental transporters can be impacted by both HIV infection and drug therapy, our objective was to explore the impact of HIV infection and cART on transporter expression. Drug transporter expression was examined in human placental samples collected from women with HIV (n = 25) and from healthy HIV(-) controls (n = 23). The effect of exposure to drugs commonly used in cART during pregnancy was examined in vitro in placental villous explants obtained from healthy women. Gene expression was measured via qRT-PCR. Several ABC (ABCG2, ABCC1,2,4) and SLC (SLC21A9, SLC22A1,3,11) transporters were significantly downregulated in placentas isolated from HIV(+) women as compared with HIV(-) controls (p < 0.05-0.001), while ABCB1 and SLC21A12 were significantly upregulated (p < 0.001). Twenty-four to 48-h exposure of human placental explants to agents used in cART resulted in significant upregulation of ABCB1 and downregulation of SLC22A11. Our findings suggest that transplacental transport may be compromised during HIV infection due to altered expression of clinically important transporters. Furthermore, in vitro results indicate that cART imposes significant alterations in placental transporters but not all changes are consistent with findings in the placenta from HIV(+) women, indicating disease effects. As this may impact in utero-fetal exposure to clinically used medications, further studies are needed to determine the overall impact on maternal-fetal transfer.

SLC Neurotransmitter Transporters as Therapeutic Targets for Alcohol Use Disorder: A Narrative Review.

Alcohol use disorder (AUD) is 1 of the most prevalent of all substance use disorders and contributes significantly to global disease burden. Despite its prevalence, <10% of individuals with AUD receive treatment. A significant barrier to receiving treatment is a lack of effective pharmacotherapies. While 3 medications have been approved by the FDA for AUD (disulfiram, acamprosate, naltrexone), their efficacy remains low. Furthermore, a number of undesirable side effects associated with these drugs further reduce patient compliance. Thus, research into new effective pharmacotherapies for AUD is warranted. Due to their involvement in regulating synaptic neurotransmitter levels, solute carrier (SLC) transporters could be targeted for developing effective treatment strategies for AUD. Indeed, a number of studies have shown beneficial reductions in alcohol consumption through the use of drugs that target transporters of dopamine, serotonin, glutamate, glycine, and GABA. The purpose of this narrative review is to summarize preclinical and clinical studies from the last 2 decades targeting SLC neurotransmitter transporters for the treatment of AUD. Limitations, as well as future directions for expanding this field, are also discussed.

Potential Limitations of Bioluminescent Xenograft Mouse Models: A Systematic Review.

PURPOSE: Bioluminescent imaging (BLI) is a versatile technique that offers non-invasive and real-time monitoring of tumor development in preclinical cancer research. However, the technique may be limited by several factors that can lead to misinterpretation of the data. This review aimed to investigate the validity of current BLI tumor models and provide recommendations for future model development. METHODS: Two major databases, MedLine and EMBASE, were searched from inception to July 2018 inclusively. Studies utilizing mouse xenograft models with demonstration of linear correlations between bioluminescent signal and tumor burden were included. Coefficients of correlation and determination were extracted along with data relating to animal model parameters. RESULTS: 116 studies were included for analysis. It was found that the majority of models demonstrate good correlation regardless of the model type. Selection of a single cell clone with highest luciferase expression resulted in a significantly better correlation. Lastly, appropriate tumor measurement techniques should be utilized when validating the BLI model. CONCLUSIONS: In general, BLI remains a valid tool for pre-clinical assessment of tumor burden. While no single factor may be identified as a general limitation, data should be interpreted with caution.

A Continuing Professional Development Program for Pharmacists Implementing Pharmacogenomics into Practice.

A continuing professional development (CPD) program for pharmacists practicing in community and team-based primary care settings was developed and evaluated using Moore's framework for the assessment of continuing medical education. The program had three components: online lectures, a two-day training workshop, and patient case studies. Knowledge (pre-post multiple choice test); attitudes, readiness, and comfort with applying pharmacogenomics in their practices (pre-post surveys); and experiences of implementing pharmacogenomics in practice (semi-structured interviews) were assessed. Twenty-one of 26 enrolled pharmacists successfully completed the program, and were satisfied with their experience. Almost all achieved a score of 80% or higher on the post-training multiple choice test, with significantly improved scores compared to the pre-training test. Pre- and post-training surveys demonstrated that participants felt that their knowledge and competence increased upon completion of the training. In the follow-up, 15 pharmacists incorporated pharmacogenomics testing into care for 117 patients. Ten pharmacists participated in semi-structured interviews, reporting strong performance in the program, but some difficulty implementing new knowledge in their practices. This multi-component CPD program successfully increased pharmacists' knowledge, readiness, and comfort in applying pharmacogenomics to patient care in the short-term, yet some pharmacists struggled to integrate this new service into their practices.

Role of Elevated SFLT-1 on the Regulation of Placental Transporters in Women With Pre-Eclampsia.

Pre-eclampsia (PE) is an obstetric complication associated with elevated levels of fms-like tyrosine kinase 1 (sFlt-1) and dysregulated trophoblast differentiation. However, limited information exists on the expression and regulation of placental drug transporters in PE. Transporter mRNA and protein expression were analyzed in human placentas diagnosed with PE (n = 34) and gestational age-matched controls (n = 24), whereas placental BeWo cells were treated with angiogenic factors in vitro. Significant downregulation of breast cancer resistance protein (BCRP) and several other transporters were seen in placentas complicated by PE compared with controls, whereas mRNA levels of sFlt-1 were induced by 2.5-fold in PE placentas (P < 0.01). Treatment of BeWo cells with sFlt-1 resulted in an 85-90% downregulation of BCRP, which was attenuated by vascular endothelial growth factor. Our findings suggest that placental function is compromised during PE due to altered expression of clinically important transporters. Furthermore, our in vitro results show that sFlt-1 is involved in the regulation of BCRP.

Dysregulation of renal transporters in a rodent model of viral Infection.

Inflammation elicited by viral mimetic poly I:C has been shown to impose changes in the expression of drug transporters in the placenta and maternal liver in rats at term pregnancy. This was associated with altered drug disposition in the mother and fetus. Renal transporters play an important role in the elimination of several drugs taken by pregnant women. We examined the impact of poly I:C on the expression of renal transporters in pregnant rats at term. Pregnant Sprague-Dawley rats received single intraperitoneal dose of either poly I:C (5 mg/kg) or saline at gestation day 18 (n = 8/group). Animals were euthanized 24 h after the injection. The mRNA and protein expression of pro-inflammatory cytokines and transporters were measured by qRT-PCR and western blot. Poly I:C caused a fourfold increase in the mRNA of IL-6 in the kidney. As compared to saline controls, the mRNA expression of Mrp2, Bcrp, Octn1, Oat1, Oat2, Oat3, Urat1, Oatp4c1, and Pept2 was downregulated, whereas the Ent1 mRNA was increased. Protein expression of Bcrp, Urat1 and Pept2 were significantly decreased. While there was a trend towards reduced Mrp2, Oat2 and Oat3 protein expression, this did not reach significance. Poly I:C did not impact mRNA levels of Mdr1a, Mdr1b, Mrp4, Oct1, Oct2, Oct3, Octn2, Mate1, Ent2 or Pept1. Viral-induced inflammation mediates significant changes in the expression of several key drug transporters in the kidney of pregnant rats. Many clinically important drugs are substrates for these transporters. Therefore, inflammation-mediated alterations in transporter expression could affect their maternal and fetal disposition.

Essential role of STAT-3 dependent NF-κB activation on IL-6-mediated downregulation of hepatic transporters.

IL-6 markedly decreases the expression of numerous hepatic transporters. We previously demonstrated that IL-6-mediated downregulation of transporters occurs through STAT3, with partial involvement of PXR. However, while IL-6-mediated induction of STAT3 occurs rapidly, repression of transporter expression is not observed until 6 h post-treatment. This temporal mismatch suggested that the downregulation of transporters following IL-6 at 6 h might require additional signaling downstream of STAT3. Since NF-κB has been implicated in endotoxin-mediated downregulation of transporters, we hypothesized that NF-κB may be similarly involved in suppressing transporter expression following IL-6. Our objective was to investigate whether IL-6-mediated changes in transporter expression occur through STAT3-dependent NF-κB activation, and whether PXR is involved. PXR null (-/-) or wild type (+/+) mice were pre-dosed with the NF-κB inhibitor PHA408 or vehicle 30 min prior to receiving a single dose of IL-6 or saline. Mice were euthanized after 6 h and transporter expression was analyzed using qRT-PCR. IL-6 imposed downregulation of Abcb1a, Abcb1b, Abcc3, Abcg2 and Cyp3a11 in both PXR (+/+) and PXR (-/-) mice, while downregulation of Abcb11, Abcc2, Slc10a1, and Slco2b1 was only significant in PXR (+/+) mice. PHA408 pretreatment fully inhibited NF-κB activation in PXR (+/+) but only partially inhibited NF-κB in PXR (-/-). Inhibition of NF-κB attenuated IL-6-mediated changes in transporters in PXR (+/+) mice. Transient transfection assays did not detect significant activation of human or mouse PXR by PHA408. Our findings suggest that IL-6 imposes significant downregulation of numerous ABC and SLC transporters in the liver via collaborative STAT3/NF-κB activation. Since drug transporters play an integral role in the pharmacokinetics of numerous clinically relevant drugs, understanding the signaling pathways involved in transporter regulation during inflammation will contribute to a better understanding of drug-disease interactions.

Impact of Viral Inflammation on the Expression of Renal Drug Transporters in Pregnant Rats.

Inflammation impacts the expression and function of drug transporters at term-gestation; however, the impact of inflammation on the expression of drug transporters at mid-gestation is largely unknown. Since renal drug transporters play a key role in the clearance of many drugs prescribed during pregnancy, our objective was to study the impact of the viral mimetic poly I:C on the expression of renal transporters in pregnant rats at mid-gestation. Poly I:C (10 mg/kg) or saline was administered intraperitoneally to pregnant Sprague-Dawley rats on gestational day 14. Expression of renal transporters was measured at 6, 24, and 48 h by qRT-PCR and Western blot. The mRNA levels of Mdr1a, Mrp4, Oct2, Octn1, Octn2, Mate1, Oat1-3, Urat1, Oatp4c1, Ent1, and Pept2 were significantly lower in the poly I:C group at 6 h. At 24 h, only the mRNA levels of Oct2, Oatp4c1, and Ent1 were decreased compared to saline. Poly I:C significantly decreased protein expression of Urat1 at 24 h, and P-gp, Oct2, Mate1, Oat1, Oat3 at 48 h,. Poly I:C imposed significant reductions in the expression of several key renal transporters at mid-gestation in pregnant rats. Thus, viral infection may impact renal excretion of drug transporter substrates, potentially leading to drug-disease interactions.

Development of a Bioluminescent BRCA1-Deficient Xenograft Model of Disseminated, High-Grade Serous Ovarian Cancer.

Successful translation of preclinical data relies on valid and comprehensive animal models. While high-grade serous ovarian cancer (HGSOC) is the most prevalent subtype, the most commonly used ovarian cancer cell lines are not representative of HGSOC. In addition, 50% of ovarian cancer patients present with dysfunctional BRCA1/2, however currently there is a shortage of BRCA-deficient models. By utilizing the OVCAR8 cell line, which contains a hypermethylated BRCA1 promoter, the aim of the current study was to establish and characterize an animal model for BRCA-deficient HGSOC. Transfection of the luciferase gene to OVCAR8 cells enabled bioluminescent imaging for real-time, non-invasive monitoring of tumor growth. The resulting model was characterized by peritoneal metastasis and ascites formation at late stages of disease. Immunohistochemical staining revealed high-grade serous histology in all resected tumor nodules. Immunoblotting and qPCR analysis demonstrated BRCA1 deficiency was maintained in vivo. Moderate to strong correlations were observed between bioluminescent signal and tumor weight. Lastly, intraperitoneal administration of carboplatin significantly reduced tumor growth as measured by bioluminescence. The current model demonstrated BRCA1 deficiency and a high resemblance of the clinical features of HGSOC. This model may be well-suited for evaluation of therapeutic efficacy in BRCA-deficient HGSOC.