Inflammation Induces Changes in the Functional Expression of P-gp, BCRP, and MRP2: An Overview of Different Models and Consequences for Drug Disposition

Drug transporter mRNA expression and genital inflammation in South African women on oral pre-exposure prophylaxis (PrEP)

Globally HIV remains a major public health problem. In sub-Saharan Africa most new HIV infections occur in adolescent girls and young women. Previously tested antiretroviral drugs as different pre-exposure prophylaxis (PrEP) formulations have shown inconsistent levels of protection against HIV in African women. Besides adherence, biological factors such as drug transporter proteins are increasingly recognized as key modulators of PrEP levels. Drug transporter mRNA expression levels has been significantly correlated to altered PrEP levels in-vitro in different tissues, with inflammation identified as a further modifier of drug transporters mRNA expression and thus PrEP levels. We therefore, aimed to determine possible concordance between drug transporter mRNA expression in the female genital tract (FGT) and blood of N = 45 South African women taking oral PrEP-Truvada® [TDF/FTC)] over 6 months for HIV prevention. Additionally, we determined associations between drug transporter mRNA expression, genital inflammation, and blood-tenofovir diphosphate (TFV-DP). mRNA-expression of four efflux P-gp; MATE-1; MRP-2; MRP-4 and two influx OAT-1 and OAT-3 drug transporters were determined by qRT-PCR. Multiplexed technology was used to measure 27 cytokines to define genital inflammation. Significant positive correlations of mRNA expression for P-gp, MATE-1, MRP-2, and MRP-4 were observed between the FGT and blood at 3- and 6-months post-PrEP initiation (p < 0.05). For OAT-1 however, significant positive correlations were observed pre- and post-PrEP exposure (p < 0.05). Linear-mixed models showed moderate associations between FGT cytokines and drug transporter mRNA expression, with a  direct relationship observed between MIP-1β concentration and MATE-1 mRNA expression. Similarly, PLS-DA showed that in women with genital inflammation, consistently higher mRNA expression of MATE-1 was observed compared to women without genital inflammation. No significant associations were observed between drug transporter mRNA expression and blood TFV-DP. Our results suggest that drug transporters may be similarly expressed in the FGT and blood. Furthermore, genital inflammation may modify PrEP levels by altering drug transporter mRNA expression. Collectively, our data may be used to better understand biological factors that may affect PrEP efficacy in African women who remain vulnerable to HIV.

Herb-drug interaction potential of Astragali Radix: a metabolic perspective

Astragali Radix (AR) is one of the most widely used herbs in Asia and has a wide range of biological activities. These activities are attributed to its various compounds like flavonoids, saponins, and polysaccharides. AR and its major components are often used in combination with other drugs for the treatment of diseases such as cancer and cerebral ischemia. With the expanding range of AR combinations, the potential for herb-drug interaction (HDI) has been raised. Key targets in HDI studies include drug-metabolizing enzymes (DMEs) and transporters. Existing studies have shown that AR and its major components have various regulatory effects on these targets, notably CYP2C9, CYP3A4, UGT1A6, and P-gp. AR may contribute to HDI when it is taken with substrates of these biomolecules, such as tolbutamide, midazolam, and digoxin. However, there are also different views in the current study, such as the effect of AR on CYP3A4. To better understand the interactions of AR with drugs, we review the metabolic pathways and pharmacokinetic parameters of the main components of AR. Meanwhile, the regulatory effects and mechanisms of AR on DMEs and transporters are summarized to provide a theoretical and technical basis for the rational use of AR in clinical practice.

The relation between inflammatory biomarkers and drug pharmacokinetics in the critically ill patients: a scoping review

BACKGROUND

The level of inflammation alters drug pharmacokinetics (PK) in critically ill patients. This might compromise treatment efficacy. Understanding the specific effects of inflammation, measured by biomarkers, on drug absorption, distribution, metabolism, and excretion is might help in optimizing dosing strategies.

OBJECTIVES

This review investigates the relationship between inflammatory biomarkers and PK parameters absorption, distribution, metabolism and excretion (ADME) in critically ill patients, providing insight in the complexity of dosing drugs in critically ill patients.

METHOD

Following PRISMA guidelines, we conducted a comprehensive search of Medline, Embase, Web of Science, and Cochrane databases (January 1946-November 2023). Studies examining inflammatory biomarkers, PK parameters, or drug exposure in critically ill patients were included. Records were screened by title, abstract, and full text, with any discrepancies resolved through discussion or consultation with a third reviewer.

RESULTS

Of the 4479 records screened, 31 met our inclusion criteria: 2 on absorption, 7 on distribution, 17 on metabolism, and 6 on excretion. In general, results are only available for a limited number of drugs, and most studies are done only looking at one of the components of ADME. Higher levels of inflammatory biomarkers may increase or decrease drug absorption depending on whether the drug undergoes hepatic first-pass elimination. For drug distribution, inflammation is negatively correlated with drug protein binding capacity, positively correlated with cerebrospinal fluid penetration, and negatively correlated with peritoneal penetration. Metabolizing capacity of most drugs was inversely correlated with inflammatory biomarkers. Regarding excretion, inflammation can lead to reduced drug clearance, except in the neonatal population.

CONCLUSION

Inflammatory biomarkers can offer valuable information regarding altered PK in critically ill patients. Our findings emphasize the need to consider inflammation-driven PK variability when individualizing drug therapy in this setting, at the same time research is limited to certain drugs and needs further research, also including pharmacodynamics.

Pleiotropic Effects of Resveratrol on Aging-Related Cardiovascular Diseases-What Can We Learn from Research in Dogs?

Resveratrol (RES) is a polyphenol with natural anti-inflammatory and antioxidant properties. It is found in abundance in plants, i.e., grapes and mulberry fruit. In addition, synthetic forms of RES exist. Since the discovery of its specific biological properties, RES has emerged as a candidate substance not only with modeling effects on the immune response but also as an important factor in preventing the onset and progression of cardiovascular disease (CVD). Previous research provided strong evidence of the effects of RES on platelets, mitochondria, cardiomyocytes, and vascular endothelial function. In addition, RES positively affects the coagulation system and vasodilatory function and improves blood flow. Not only in humans but also in veterinary medicine, cardiovascular diseases have one of the highest incidence rates. Canine and human species co-evolved and share recent evolutionary selection processes, and interestingly, numerous pathologies of companion dogs have a human counterpart. Knowledge of the impact of RES on the cardiovascular system of dogs is becoming clearer in the literature. Dogs have long been recognized as valuable animal models for the study of various human diseases as they share many physiological and genetic similarities with humans. In this review, we aim to shed light on the pleiotropic effects of resveratrol on cardiovascular health in dogs as a translational model for human cardiovascular diseases.

Inflammation alters the expression pattern of drug transporters during Caco-2 cell stimulation and azoxymethane-induced colon tumorigenesis

Drug transporters play a pivotal role in modulating drug disposition and are subject to alterations under inflammatory conditions. This study aimed to elucidate the intricate expression patterns of drug transporters during both acute and chronic inflammation, which are closely linked to malignant transformation. To investigate acute inflammation, we employed an in vitro model by subjecting Caco-2 cells to various inflammatory stimuli (IL-1β, TNF-α, or LPS) individually or in combination. The successful induction of inflammation was confirmed by robust increases in IL-6 and NO production. Notably, inflamed Caco-2 cells exhibited significantly diminished levels of ABCB1 and ABCG2, while the expression of ABCC2 was upregulated. For chronic inflammation induction in vivo, we employed the well-established AOM/DSS mouse model known for its association with colitis-driven tumorigenesis. Persistent inflammation was effectively monitored throughout the experiment via elevated IL-6 and NO levels. The sequential stages of tumorigenesis were confirmed through Ki-67 immunohistochemistry. Intriguingly, we observed gradual alterations in the expression patterns of the studied drug transporters during stepwise induction, with ABCB1, ABCG2, and ABCC1 showing downregulation and ABCC2 exhibiting upregulation. Immunohistochemistry further revealed dynamic changes in the expression of ABCB1 and ABCC2 during the induction cycles, closely paralleling the gradual increase in Ki-67 expression observed during the development of precancerous lesions. Collectively, our findings underscore the significant impact of inflammation on drug transporter expression, potentially influencing the process of malignant transformation of the colon.

Impacts of genetic polymorphisms and cancer cachexia on naldemedine pharmacokinetics and bowel movements in patients receiving opioid analgesics

BACKGROUND/OBJECTIVES

Clinical responses to naldemedine vary between individuals with advanced cancer. This is a prospective, single-center, observational study aimed to evaluate the influence of genetic polymorphisms and cachexia status on plasma naldemedine and clinical responses.

METHODS

Forty-eight patients being treated with naldemedine for opioid-induced constipation under treatment of cancer pain were enrolled. Plasma naldemedine concentrations were determined on the fourth day or later after administration of naldemedine, and the associations with genotypes, cachexia status, and clinical responses were assessed.

RESULTS

Cancer patients exhibited a large variation in the plasma naldemedine concentrations, and it was correlated with serum total protein level. Patients who were homozygous CYP3A5*3 had a higher plasma concentration of naldemedine than those with the *1 allele. ABCB1 genotypes tested in this study were not associated with plasma naldemedine. A negative correlation was observed between the plasma naldemedine concentration and 4β-hydroxycholesterol level. The plasma naldemedine concentration was lower in patients with refractory cachexia than in those with precachexia and cachexia. While serum levels of interleukin-6 (IL-6) and acute-phase proteins were higher in patients with refractory cachexia, they were not associated with plasma naldemedine. A higher plasma concentration of naldemedine, CYP3A5*3/*3, and an earlier naldemedine administration after starting opioid analgesics were related to improvement of bowel movements.

CONCLUSION

Plasma naldemedine increased under deficient activity of CYP3A5 in cancer patients. Cachectic patients with a higher serum IL-6 had a lower plasma naldemedine. Plasma naldemedine, related to CYP3A5 genotype, and the initiation timing of naldemedine were associated with improved bowel movements.

Roles of breast cancer resistance protein and organic anion transporting polypeptide 2B1 in gastrointestinal toxicity induced by SN-38 under inflammatory conditions

Drug transporters are among the factors that determine the pharmacokinetic profiles after drug administration. In this study, we investigated the roles of drug transporters involved in transport of SN-38, which is an active metabolite of irinotecan, in the intestine under inflammatory conditions in vitro and determined their functional consequences. The expression alterations of breast cancer resistance protein (BCRP) and organic anion transporting polypeptide (OATP) 2B1 were determined at the mRNA and protein levels, and the subsequent functional alterations were evaluated via an accumulation study with the representative transporter substrates [prazosin and dibromofluorescein (DBF)] and SN-38. We also determined the cytotoxicity of SN-38 under inflammatory conditions. Decreased BCRP expression and increased OATP2B1 expression were observed under inflammatory conditions in vitro, which led to altered accumulation profiles of prazosin, DBF, and SN-38, and the subsequent cytotoxic profiles of SN-38. Treatment with rifampin or novobiocin supported the significant roles of BCRP and OATP2B1 in the transport and cytotoxic profile of SN-38. Collectively, these results suggest that BCRP and OATP2B1 are involved in the increased cytotoxicity of SN-38 under inflammatory conditions in vitro. Further comprehensive research is warranted to completely understand SN-38-induced gastrointestinal cytotoxicity and aid in the successful treatment of cancer with irinotecan.

Pharmacokinetic and pharmacodynamic principles: unique considerations for optimal design of neonatal clinical trials

Core clinical pharmacology principles must be considered when designing and executing neonatal clinical trials. In this review, the authors discuss important aspects of drug dose selection, pharmacokinetics, pharmacogenetics and pharmacodynamics that stakeholders may consider when undertaking a neonatal or infant clinical trial.

Gene Expression of Abcc2 and Its Regulation by Chicken Xenobiotic Receptor

Membrane transporter multidrug resistance-associated protein 2 (MRP2/Abcc2) exhibits high pharmaco-toxicological relevance because it exports multiple cytotoxic compounds from cells. However, no detailed information about the gene expression and regulation of MRP2 in chickens is yet available. Here, we sought to investigate the expression distribution of Abcc2 in different tissues of chicken and then determine whether Abcc2 expression is induced by chicken xenobiotic receptor (CXR). The bioinformatics analyses showed that MRP2 transporters have three transmembrane structural domains (MSDs) and two highly conserved nucleotide structural domains (NBDs), and a close evolutionary relationship with turkeys. Tissue distribution analysis indicated that Abcc2 was highly expressed in the liver, kidney, duodenum, and jejunum. When exposed to metyrapone (an agonist of CXR) and ketoconazole (an antagonist of CXR), Abcc2 expression was upregulated and downregulated correspondingly. We further confirmed that Abcc2 gene regulation is dependent on CXR, by overexpressing and interfering with CXR, respectively. We also demonstrated the induction of Abcc2 expression and the activity of ivermectin, with CXR being a likely mediator. Animal experiments demonstrated that metyrapone and ivermectin induced Abcc2 in the liver, kidney, and duodenum of chickens. Together, our study identified the gene expression of Abcc2 and its regulation by CXR in chickens, which may provide novel targets for the reasonable usage of veterinary drugs.

Intestinal Membrane Function in Inflammatory Bowel Disease

Inflammatory bowel disease is a set of chronic inflammatory diseases that mainly develop in the gastrointestinal mucosa, including ulcerative colitis and Crohn's disease. Gastrointestinal membrane permeability is an important factor influencing the pharmacological effects of pharmaceuticals administered orally for treating inflammatory bowel disease and other diseases. Understanding the presence or absence of changes in pharmacokinetic properties under a disease state facilitates effective pharmacotherapy. In this paper, we reviewed the gastrointestinal membrane function in ulcerative colitis and Crohn's disease from the perspective of in vitro membrane permeability and electrophysiological parameters. Information on in vivo permeability in humans is summarized. We also overviewed the inflammatory bowel disease research using gut-on-a-chip, in which some advances have recently been achieved. It is expected that these findings will be exploited for the development of therapeutic drugs for inflammatory bowel disease and the optimization of treatment options and regimens.

Changes in Psychotropic Drug Blood Levels After SARS-CoV-2 Vaccination: A Two-Center Cohort Study

BACKGROUND

Limited evidence from case reports suggests that coronavirus disease 2019 (COVID-19) vaccination may interact with the treatment outcomes of psychiatric medications. Apart from clozapine, reports on the effect of COVID-19 vaccination on other psychotropic agents are scarce. This study aimed to investigate the impact of COVID-19 vaccination on the plasma levels of different psychotropic drugs using therapeutic drug monitoring.

METHODS

Plasma levels of psychotropic agents, including agomelatine, amisulpride, amitriptyline, escitalopram, fluoxetine, lamotrigine, mirtazapine, olanzapine, quetiapine, sertraline, trazodone, and venlafaxine, from inpatients with a broad spectrum of psychiatric diseases receiving COVID-19 vaccinations were collected at 2 medical centers between 08/2021 and 02/2022 under steady-state conditions before and after vaccination. Postvaccination changes were estimated as a percentage of baseline.

RESULTS

Data from 16 patients who received COVID-19 vaccination were included. The largest changes in plasma levels were reported for quetiapine (+101.2%) and trazodone (-38.5%) in 1 and 3 patients, respectively, 1 day postvaccination compared with baseline levels. One week postvaccination, the plasma levels of fluoxetine (active moiety) and escitalopram increased by 31% and 24.9%, respectively.

CONCLUSIONS

This study provides the first evidence of major changes in the plasma levels of escitalopram, fluoxetine, trazodone, and quetiapine after COVID-19 vaccination. When planning COVID-19 vaccination for patients treated with these medications, clinicians should monitor rapid changes in bioavailability and consider short-term dose adjustments to ensure safety.

Study Models of Drug-Drug Interactions Involving P-Glycoprotein: The Potential Benefit of P-Glycoprotein Modulation at the Kidney and Intestinal Levels

P-glycoprotein (P-gp) is a crucial membrane transporter situated on the cell's apical surface, being responsible for eliminating xenobiotics and endobiotics. P-gp modulators are compounds that can directly or indirectly affect this protein, leading to changes in its expression and function. These modulators can act as inhibitors, inducers, or activators, potentially causing drug-drug interactions (DDIs). This comprehensive review explores diverse models and techniques used to assess drug-induced P-gp modulation. We cover several approaches, including in silico, in vitro, ex vivo, and in vivo methods, with their respective strengths and limitations. Additionally, we explore the therapeutic implications of DDIs involving P-gp, with a special focus on the renal and intestinal elimination of P-gp substrates. This involves enhancing the removal of toxic substances from proximal tubular epithelial cells into the urine or increasing the transport of compounds from enterocytes into the intestinal lumen, thereby facilitating their excretion in the feces. A better understanding of these interactions, and of the distinct techniques applied for their study, will be of utmost importance for optimizing drug therapy, consequently minimizing drug-induced adverse and toxic effects.

Exploring the heterogeneous transcriptional response of the CNS to systemic LPS and Poly(I:C)

Peripheral contact to pathogen-associated molecular patterns (PAMPs) evokes a systemic innate immune response which is rapidly relayed to the central nervous system (CNS). The remarkable cellular heterogeneity of the CNS poses a significant challenge to the study of cell type and stimulus dependent responses of neural cells during acute inflammation. Here we utilized single nuclei RNA sequencing (snRNAseq), serum proteome profiling and primary cell culture methods to systematically compare the acute response of the mammalian brain to the bacterial PAMP lipopolysaccharide (LPS) and the viral PAMP polyinosinic:polycytidylic acid (Poly(I:C)), at single cell resolution. Our study unveiled convergent transcriptional cytokine and cellular stress responses in brain vascular and ependymal cells and a downregulation of several key mediators of directed blood brain barrier (BBB) transport. In contrast the neuronal response to PAMPs was limited in acute neuroinflammation. Moreover, our study highlighted the dominant role of IFN signalling upon Poly(I:C) challenge, particularly in cells of the oligodendrocyte lineage. Collectively our study unveils heterogeneous, shared and distinct cell type and stimulus dependent acute responses of the CNS to bacterial and viral PAMP challenges. Our findings highlight inflammation induced dysregulations of BBB-transporter gene expression, suggesting potential translational implications on drug pharmacokinetics variability during acute neuroinflammation. The pronounced dependency of oligodendrocytes on IFN stimulation during viral PAMP challenges, emphasizes their limited molecular viral response repertoire.

Exosomes; multifaceted nanoplatform for targeting brain cancers

At the moment, anaplastic changes within the brain are challenging due to the complexity of neural tissue, leading to the inefficiency of therapeutic protocols. The existence of a cellular interface, namely the blood-brain barrier (BBB), restricts the entry of several macromolecules and therapeutic agents into the brain. To date, several nano-based platforms have been used in laboratory settings and in vivo conditions to overcome the barrier properties of BBB. Exosomes (Exos) are one-of-a-kind of extracellular vesicles with specific cargo to modulate cell bioactivities in a paracrine manner. Regarding unique physicochemical properties and easy access to various biofluids, Exos provide a favorable platform for drug delivery and therapeutic purposes. Emerging data have indicated that Exos enable brain penetration of selective cargos such as bioactive factors and chemotherapeutic compounds. Along with these statements, the application of smart delivery approaches can increase delivery efficiency and thus therapeutic outcomes. Here, we highlighted the recent advances in the application of Exos in the context of brain tumors.

Using simulations to explore the potential effect of disease and inflammation on the frequency of violative flunixin residues in cattle

The US Food and Drug Administration (FDA) assigns a tolerance and withdrawal period when evaluating new drugs for use in food-producing species. Because withdrawal periods are determined from data generated in normal, healthy animals, questions have been raised regarding whether disease and inflammation can be a factor associated with some residue violations. We explored this question using flunixin liver concentrations as a model situation. Using data contained in the flunixin FOI Summary (NADA 101-479) and Monte Carlo simulation, we generated sets of residue depletion data. Our mathematical model was simple linear regression containing the terms alpha (the marker residue back-extrapolated to time zero, which equals ln C 0 ) and beta (the elimination rate constant which equals - k e ). By modifying alpha and beta means and variances, we determined the smallest change in these parameters that would result in the presence of violative residues above the statistically determined expected frequency of 1%. The results of this in silico study indicated that the magnitude of change in alpha and beta needed to generate violative residues exceeds that likely to occur due to disease or inflammation when flunixin is used in accordance with the approved product label.

Effects of whole-brain radiation therapy on the blood-brain barrier in immunocompetent and immunocompromised mouse models

BACKGROUND

Approximately 20% of all cancer patients will develop brain metastases in their lifespan. The standard of care for patients with multiple brain metastases is whole-brain radiation therapy, which disrupts the blood-brain barrier. Previous studies have shown inflammatory mediators play a role in the radiation-mediated increase in permeability. Our goal was to determine if differential permeability post-radiation occurs between immunocompetent and immunocompromised mice.

METHODS

We utilized a commissioned preclinical irradiator to irradiate brains of C57Bl/6J wild-type and athymic nude mice. Acute (3-24 h) effects on blood-brain barrier integrity were evaluated with our in-situ brain perfusion technique and quantitative fluorescent and phosphorescent microscopy. The presence of inflammatory mediators in the brain and serum was determined with a proinflammatory cytokine panel.

RESULTS

Blood-brain barrier integrity and efflux transporter activity were altered in the immunocompetent mice 12 h following irradiation without similar observations in the immunocompromised mice. We observed increased TNF-α concentrations in the serum of wild-type mice immediately post-radiation and nude mice 12 h post-radiation. The brain concentration of CXCL1 was also increased in both mouse strains at the 12-h time point.

CONCLUSIONS

The immune response plays a role in the magnitude of blood-brain barrier disruption following irradiation in a time- and size-dependent manner.

P-Glycoprotein and Organic Anion Transporter Polypeptide 1B/Breast Cancer Resistance Protein Drug Transporter Activity in Pregnant Women Living With HIV

This study evaluates the influence of pregnancy and HIV infection in conjunction with the use of raltegravir, lamivudine, and tenofovir disoproxil fumarate (combined antiretroviral therapy [cART]) on intestinal P-glycoprotein (P-gp) and hepatic organic anion transporter polypeptide (OATP) 1B1/1B3 and/or breast cancer resistance protein (BCRP) drug transporter activity using rosuvastatin (OATP1B/BCRP) and fexofenadine (P-gp) probes. Single oral doses of 5-mg rosuvastatin and 60-mg fexofenadine were administered to women living with HIV under cART in the third trimester of gestation (n = 15) and postpartum period (n = 10). A control group of 12 healthy nonpregnant women also was investigated. Pharmacokinetic parameters were estimated by using a noncompartmental method and evaluated by t test (P < .05). The rosuvastatin area under the plasma concentration-time curve from time 0 to the last quantifiable concentration (AUC_0-last ) value was higher in the third trimester of pregnancy (19.5 [95%CI, 16.8-22.3] ng • h/mL] when compared to postpartum (13.3 [95%CI, 9.3-17.5] ng • h/mL), while the fexofenadine AUC_0-last values did not differ between the third trimester of pregnancy (738.0 [95%CI, 611.4-864.6] ng • h/mL) and postpartum period (874.9 [95%CI, 408.2-1342.0] ng• h/mL). The rosuvastatin AUC_0-last values did not differ between healthy nonpregnant women (13.8 [95%CI, 10.0-17.6] ng • h/mL) and women living with HIV in the postpartum period (13.3 [95%CI, 9.3-17.5] ng • h/mL), and the fexofenadine AUC_0-last values did not differ between the 2 investigated groups (603.6 [95%CI, 467.5-739.7] ng • h/mL vs 874.9 [95%CI, 408.2-1342.0] ng • h/mL). It is suggested that gestation inhibits the hepatic OATP1B1/1B3 and/or BCRP activity but does not alter intestinal P-gp activity. The influence of HIV infection in conjunction with use of cART on OATP1B/BCRP and intestinal P-gp activity was not observed.

A review: Pharmacokinetics and pharmacology of aminoalcohol-diterpenoid alkaloids from Aconitum species

ETHNOPHARMACOLOGICAL RELEVANCE

Aconitum medicinal materials, such as Aconitum carmichaelii Debeaux (Chinese: Wutou/) and Aconitum kusnezoffii Reichb. (Chinese: Caowu/), are a kind of important Traditional Chinese Medicine (TCM) with great medicinal value. Statistics show that there are over 600 efficient TCM formulations comprising Aconitum medicinal materials. But high toxicity limits their clinical application. Clinically, the Aconitum medicinal materials must undergo a complex processing process that includes soaking, steaming, and boiling with pharmaceutical excipients, which makes highly toxic ester diterpenoid alkaloids are hydrolyzed to form less toxic aminoalcohol-diterpenoid alkaloids (ADAs).

AIM OF THE STUDY

This review aims to summarize the pharmacokinetic and pharmacological activities of low-toxicity ADAs, providing a reference for future ADAs research and drug development.

MATERIALS AND METHODS

Accessible literature on ADAs published between 1984 and 2022 were screened and obtained from available electronic databases such as PubMed, Web of Science, Springer, Science Direct and Google Scholar, followed by systematic analysis.

RESULTS

ADAs are secondary products of plant metabolism, widely distributed in the Aconitum species and Delphinium species. The toxicity of ADAs as pharmacodynamic components of Aconitum medicinal materials is much lower than that of other diterpenoid alkaloids due to the absence of ester bonds. On the one hand, the pharmacokinetics of ADAs have received little attention compared to other toxic alkaloids. The research primarily focuses on aconine and mesaconine. According to existing studies, ADAs absorption in the gastrointestinal tract is primarily passive with a short T_max. Simultaneously, efflux transporters have less impact on ADAs absorption than non-ADAs. After entering the body, ADAs are widely distributed in the heart, liver, lungs, and kidney, but less in the brain. Notably, aconine is not well metabolized by liver microsomes. Aconine and mesaconine are excreted in urine and feces, respectively. ADAs, on the other hand, have been shown to have a variety of pharmacological activities, including cardiac, analgesic, anti-inflammatory, anti-tumor, antioxidant, and regenerative effects via regulating multiple signaling pathways, including Nrf2/ARE, PERK/eIF2α/ATF4/Chop, ERK/CREB, NF-κB, Bcl-2/Bax, and GSK3β/β-catenin signaling pathways.

CONCLUSIONS

ADAs have been shown to have beneficial effects on heart disease, neurological disease, and other systemic diseases. Moreover, ADAs have low toxicity and a wide range of safe doses. All of these suggest that ADAs have great potential for drug development.

Pharmacogenomics of drug transporters for antiretroviral long-acting pre-exposure prophylaxis for HIV

The use of antiretrovirals (ARVs) as oral, topical, or long-acting pre-exposure prophylaxis (PrEP) has emerged as a promising strategy for HIV prevention. Clinical trials testing Truvada® [tenofovir disoproxil fumarate (TDF)/tenofovir (TFV) and emtricitabine (FTC)] as oral or topical PrEP in African women showed mixed results in preventing HIV infections. Since oral and topical PrEP effectiveness is dependent on adequate drug delivery and availability to sites of HIV infection such as the blood and female genital tract (FGT); host biological factors such as drug transporters have been implicated as key regulators of PrEP. Drug transporter expression levels and function have been identified as critical determinants of PrEP efficacy by regulating PrEP pharmacokinetics across various cells and tissues of the blood, renal tissues, FGT mucosal tissues and other immune cells targeted by HIV. In addition, biological factors such as genetic polymorphisms and genital inflammation also influence drug transporter expression levels and functionality. In this review, drug transporters and biological factors modulating drug transporter disposition are used to explain discrepancies observed in PrEP clinical trials. This review also provides insight at a pharmacological level of how these factors further increase the susceptibility of the FGT to HIV infections, subsequently contributing to ineffective PrEP interventions in African women.

Pros and cons of NRF2 activation as adjunctive therapy in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease with an important inflammatory component accompanied by deregulated redox-dependent signaling pathways that are feeding back into inflammation. In this context, we bring into focus the transcription factor NRF2, a master redox regulator that exerts exquisite antioxidant and anti-inflammatory effects. The review does not intend to be exhaustive, but to point out arguments sustaining the rationale for applying an NRF2-directed co-treatment in RA as well as its potential limitations. The involvement of NRF2 in RA is emphasized through an analysis of publicly available transcriptomic data on NRF2 target genes and the findings from NRF2-knockout mice. The impact of NRF2 on concurrent pathologic mechanisms in RA is explained by its crosstalk with major redox-sensitive inflammatory and cell death-related pathways, in the context of the increased survival of pathologic cells in RA. The proposed adjunctive therapy targeted to NRF2 is further sustained by the existence of promising NRF2 activators that are in various stages of drug development. The interference of NRF2 with conventional anti-rheumatic therapies is discussed, including the cytoprotective effects of NRF2 for alleviating drug toxicity. From another perspective, the review presents how NRF2 activation would be decreasing the efficacy of synthetic anti-rheumatic drugs by increasing drug efflux. Future perspectives regarding pharmacologic NRF2 activation in RA are finally proposed.

TNF-α and IL-1β Exposure Modulates the Expression and Functionality of P-Glycoprotein in Intestinal and Renal Barriers

Inflammation is characterized by an increased secretion of proinflammatory cytokines known to alter the expression and functionality of drug transporters. Since P-glycoprotein (P-gp) plays a key role in the pharmacokinetics of several drugs, these modulations could further affect drug exposure. In this context, this study aims to investigate the impact of in vitro cytokine exposure on the expression and activity of P-gp using the intestinal model Caco-2 and the human renal cells RPTEC/TERT1. Cells were exposed to various concentrations of tumor necrosis factor (TNF)-α and interleukin (IL)-1β for 24 or 72 h. Gene expression was then assessed by RT-qPCR followed by absolute quantification of P-gp using liquid chromatography coupled with mass spectrometry. Then, the activity of P-gp was assessed by the intracellular accumulation of rhodamine 123. TNF-α increased both the gene expression and P-gp activity by 15-40% in each model. Minor modulations were observed at the protein level with increases of up to 8% for RPTEC/TERT1 cells and 24% for Caco-2 cells. Conversely, IL-1β led to a downregulation of gene, protein, and functionality by 48 and 25% in intestinal and renal cells, respectively. Taken together, these data highlighted that gene expression levels and functional activity of P-gp are altered by the pro-inflammatory cytokines in intestinal and renal cells. Such pronounced changes in human P-gp could result in altered exposure to drug substrates. Further in vivo studies are needed to confirm the impact of inflammation on drug pharmacokinetics.

Changes in the expression of drug-metabolising enzymes and drug transporters in mice with collagen antibody-induced arthritis

1. We investigated the changes in the expression of drug-metabolising enzymes and drug transporters in the liver, small intestine and kidney of mice with collagen antibody-induced arthritis (CAIA) to determine whether changes in these expressions affect pharmacokinetics of drugs in patients with rheumatoid arthritis.2. mRNA expression levels of cytochrome P450 (Cyp) 2b10, Cyp2c29 and Cyp3a11 were observed to be lower in the liver and small intestine of CAIA mice than in control mice. Compared with control mice, mRNA expression levels of multidrug resistance 1 b, peptide transporter 2 and organic anion transporter (Oat) 2 were high in the liver of CAIA mice. Changes in these expression levels were different among organs. However, elevated expression of Oat2 mRNA was not associated with an increase in protein expression and transport activity evaluated using [³H]cGMP as a substrate.3. These results suggest that arthritis can change the expression of pharmacokinetics-related genes, but the changes may not necessarily be linked to the pharmacokinetics in patients with rheumatoid arthritis. On the other hand, we found Oat2 mRNA expression level was positively correlated with plasma interleukin-6 level, indicating that transcriptional activation of Oat2 may occur in inflammatory state.

Pharmacokinetic Imaging Using 99mTc-Mebrofenin to Untangle the Pattern of Hepatocyte Transporter Disruptions Induced by Endotoxemia in Rats

Endotoxemia-induced inflammation may impact the activity of hepatocyte transporters, which control the hepatobiliary elimination of drugs and bile acids. ^99mTc-mebrofenin is a non-metabolized substrate of transporters expressed at the different poles of hepatocytes. ^99mTc-mebrofenin imaging was performed in rats after the injection of lipopolysaccharide (LPS). Changes in transporter expression were assessed using quantitative polymerase chain reaction of resected liver samples. Moreover, the particular impact of pharmacokinetic drug–drug interactions in the context of endotoxemia was investigated using rifampicin (40 mg/kg), a potent inhibitor of hepatocyte transporters. LPS increased ^99mTc-mebrofenin exposure in the liver (1.7 ± 0.4-fold). Kinetic modeling revealed that endotoxemia did not impact the blood-to-liver uptake of ^99mTc-mebrofenin, which is mediated by organic anion-transporting polypeptide (Oatp) transporters. However, liver-to-bile and liver-to-blood efflux rates were dramatically decreased, leading to liver accumulation. The transcriptomic profile of hepatocyte transporters consistently showed a downregulation of multidrug resistance-associated proteins 2 and 3 (Mrp2 and Mrp3), which mediate the canalicular and sinusoidal efflux of ^99mTc-mebrofenin in hepatocytes, respectively. Rifampicin effectively blocked both the Oatp-mediated influx and the Mrp2/3-related efflux of ^99mTc-mebrofenin. The additive impact of endotoxemia and rifampicin led to a 3.0 ± 1.3-fold increase in blood exposure compared with healthy non-treated animals. ^99mTc-mebrofenin imaging is useful to investigate disease-associated change in hepatocyte transporter function.