Saudi Med J. 2022 Jan;43(1):37-44. doi: 10.15537/smj.2022.43.1.20210574.

ABSTRACT

OBJECTIVES: To investigate the anti-tumor activity and tolerability of celecoxib as an adjuvant therapy for patients with metastatic colorectal cancer (CRC).

METHODS: In this randomized controlled study, 54 patients with metastatic CRC were randomized into 2 groups; the control group (n=28) which received 6 cycles of folinic acid, fluorouracil and irinotecan (FOLFIRI) regimen (5-flourouracil, leucovorin, irinotecan), and the celecoxib group (n=26) which received 6 cycles of FOLFIRI regimen plus celecoxib 200 mg twice daily. The study duration was 3 months. Patients were assessed at baseline and at the end of intervention through the Response Evaluation Criteria in Solid Tumors objective response rate (ORR) and through evaluating the serum concentrations of vascular endothelial growth factor (VEGF), soluble factor-related apoptosis (sFAS), sFAS ligand (sFASL), and epithelial neutrophil-activating peptide -78 (ENA-78/CXCL5). Common Terminology Criteria for Adverse Events version 6.0 was used for evaluating drug-related toxicity.

RESULTS: After intervention, celecoxib/FOLFIRI arm showed significant elevation in ORR as compared to FOLFIRI arm (p=0.001). As compared to FOLFIRI arm, celecoxib/FOLFIRI arm showed significantly lower VEGF (p<0.001), CXCL5 (p<0.001), and sFASL (p<0.001) serum levels and significantly higher sFAS serum level and sFAS/FASL ratio (p<0.001). Furthermore, celecoxib/FOLFIRI arm showed significantly higher progression-free survival and one-year overall survival when compared to FOLFIRI arm.

CONCLUSION: Celecoxib plus chemotherapy may represent an effective and safe synergetic protocol for patients with metastatic CRC.Clinicaltrial.gov ID:NCT03645187.

PMID:35022282 | DOI:10.15537/smj.2022.43.1.20210574

Reg Anesth Pain Med. 2022 Jan 12:rapm-2021-103364. doi: 10.1136/rapm-2021-103364. Online ahead of print.

NO ABSTRACT

PMID:35022263 | DOI:10.1136/rapm-2021-103364

Pharmacol Rev. 2022 Jan;74(1):141-206. doi: 10.1124/pharmrev.120.000238.

ABSTRACT

The number of successful drug development projects has been stagnant for decades despite major breakthroughs in chemistry, molecular biology, and genetics. Unreliable target identification and poor translatability of preclinical models have been identified as major causes of failure. To improve predictions of clinical efficacy and safety, interest has shifted to three-dimensional culture methods in which human cells can retain many physiologically and functionally relevant phenotypes for extended periods of time. Here, we review the state of the art of available organotypic culture techniques and critically review emerging models of human tissues with key importance for pharmacokinetics, pharmacodynamics, and toxicity. In addition, developments in bioprinting and microfluidic multiorgan cultures to emulate systemic drug disposition are summarized. We close by highlighting important trends regarding the fabrication of organotypic culture platforms and the choice of platform material to limit drug absorption and polymer leaching while supporting the phenotypic maintenance of cultured cells and allowing for scalable device fabrication. We conclude that organotypic and microphysiological human tissue models constitute promising systems to promote drug discovery and development by facilitating drug target identification and improving the preclinical evaluation of drug toxicity and pharmacokinetics. There is, however, a critical need for further validation, benchmarking, and consolidation efforts ideally conducted in intersectoral multicenter settings to accelerate acceptance of these novel models as reliable tools for translational pharmacology and toxicology. SIGNIFICANCE STATEMENT: Organotypic and microphysiological culture of human cells has emerged as a promising tool for preclinical drug discovery and development that might be able to narrow the translation gap. This review discusses recent technological and methodological advancements and the use of these systems for hit discovery and the evaluation of toxicity, clearance, and absorption of lead compounds.

PMID:35017176 | DOI:10.1124/pharmrev.120.000238

Neurodegener Dis Manag. 2022 Jan 12. doi: 10.2217/nmt-2021-0041. Online ahead of print.

ABSTRACT

People with multiple sclerosis (also shortened to MS) may have difficulties staying on treatment due to side effects. Cladribine tablets, approved for treating relapsing forms of MS, are given by mouth for four short periods over two years. The benefit of convenient dosing may be lost if side effects prevent people with MS from finishing their treatment. This is the summary of a study that examined side effects from cladribine tablets treatment in the first 12 weeks of two clinical studies called CLARITY and ORACLE-MS. Overall, 34.7% of participants who took cladribine tablets experienced drug-related side effects compared to 23.2% of participants who took placebo. Most side effects were mild and were seen in 54.8% of participants taking cladribine tablets and 59.1% taking the placebo. A low number of participants discontinued treatment due to side effects (1.6% of participants who took cladribine tablets; 1.4% of participants who took placebo). The researchers concluded that cladribine tablets are well-tolerated and people with MS are likely to complete the full treatment course. ClinicalTrials.gov NCT numbers: CLARITY study - NCT00213135 and ORACLE-MS study - NCT00725985.

PMID:35019731 | DOI:10.2217/nmt-2021-0041

Drug Ther Bull. 2022 Jan 11:dtb-2021-000073. doi: 10.1136/dtb.2021.000073. Online ahead of print.

NO ABSTRACT

PMID:35017166 | DOI:10.1136/dtb.2021.000073

Drug Ther Bull. 2022 Jan 11:dtb-2021-000072. doi: 10.1136/dtb.2021.000072. Online ahead of print.

NO ABSTRACT

PMID:35017165 | DOI:10.1136/dtb.2021.000072

Int J Environ Res Public Health. 2021 Dec 31;19(1):413. doi: 10.3390/ijerph19010413.

ABSTRACT

All medicinal products authorized in the European Union are subjects of constant drug-safety monitoring processes. It is organized in a pharmacovigilance system that is designed to protect human health and life by the detection, analysis and prevention of adverse drug reactions (ADRs) and other drug-related problems. The main role of the aforementioned system is to collect and analyze adverse drug reaction reports. Legislation introduced several years ago allowed patients, their legal representatives and caregivers to report adverse drug reactions, which caused them to be an additional source of safety data. This paper presents the analysis of EudraVigilance data related to adverse drug reactions provided by patients, their representatives, as well as those obtained from healthcare professionals related to medicines which belong to M01A anti-inflammatory and antirheumatic products, a non-steroid group. The objective of the study was to identify the changes in the number and structure of adverse reaction reporting after the introduction of pharmacovigilance (PV) obligations in EU. A review of scientific literature was also conducted to assess the differences in adverse reactions reported by patients or their representatives and by healthcare professionals. We also identified other factors which, according to literature review, influenced the number of adverse reaction reports provided by patients. Analysis of data collected from the EudraVigilance showed that from 2011 to 2013 the number of reports made by patients and their caregivers increased by approx. 24 percentage points, and then, from 2014, it constituted around 30% of the total of reported reactions every year, so patient reporting is an important part of pharmacovigilance system and a source of drugs' safety information throughout their use in healthcare practice. Additionally, there was no interrelationship between the seriousness of reported adverse reactions and the overall number of patient reports when compared to reports form healthcare professionals.

PMID:35010673 | PMC:PMC8745009 | DOI:10.3390/ijerph19010413

Int J Mol Sci. 2021 Dec 22;23(1):82. doi: 10.3390/ijms23010082.

ABSTRACT

Using drugs to treat COVID-19 symptoms may induce adverse effects and modify patient outcomes. These adverse events may be further aggravated in obese patients, who often present different illnesses such as metabolic-associated fatty liver disease. In Rennes University Hospital, several drug such as hydroxychloroquine (HCQ) have been used in the clinical trial HARMONICOV to treat COVID-19 patients, including obese patients. The aim of this study is to determine whether HCQ metabolism and hepatotoxicity are worsened in obese patients using an in vivo/in vitro approach. Liquid chromatography high resolution mass spectrometry in combination with untargeted screening and molecular networking were employed to study drug metabolism in vivo (patient's plasma) and in vitro (HepaRG cells and RPTEC cells). In addition, HepaRG cells model were used to reproduce pathophysiological features of obese patient metabolism, i.e., in the condition of hepatic steatosis. The metabolic signature of HCQ was modified in HepaRG cells cultured under a steatosis condition and a new metabolite was detected (carboxychloroquine). The RPTEC model was found to produce only one metabolite. A higher cytotoxicity of HCQ was observed in HepaRG cells exposed to exogenous fatty acids, while neutral lipid accumulation (steatosis) was further enhanced in these cells. These in vitro data were compared with the biological parameters of 17 COVID-19 patients treated with HCQ included in the HARMONICOV cohort. Overall, our data suggest that steatosis may be a risk factor for altered drug metabolism and possibly toxicity of HCQ.

PMID:35008505 | PMC:PMC8744768 | DOI:10.3390/ijms23010082

J Mater Chem B. 2022 Jan 11. doi: 10.1039/d1tb01961a. Online ahead of print.

ABSTRACT

Myocardial infarction (MI) has been considered as the leading cause of cardiovascular-related deaths worldwide. Basic fibroblast growth factor (bFGF) is a member of the fibroblast growth factor family that promotes angiogenesis after MI; however, it has poor clinical efficacy due to proteolytic degradation, low drug accumulation, and severe drug-induced side effects. In this study, an injectable disulfide-cross-linked chitosan hydrogel loaded with bFGF was prepared via a thiol-disulfide exchange reaction for MI treatment. The thiol-disulfide exchange reaction between pyridyl disulfide-modified carboxymethyl chitosan (CMCS-S-S-Py) and reduced BSA (rBSA) was carried out under physiological conditions (37 °C and pH 7.4). The mechanical properties of the disulfide-cross-linked chitosan hydrogel were evaluated based on the molar ratio of the pyridyl disulfide groups of CMCS-S-S-Py and the thiol groups of rBSA. The disulfide-cross-linked chitosan hydrogel showed good swelling performance, rapid glutathione-triggered degradation behavior and well-defined cell proliferation towards NIH 3T3 fibroblast cells. In the process of establishing a rat MI model, the squeezing heart method was used to make the operation more accurate and the mortality of rats was decreased by using a ventilator. The disulfide-cross-linked chitosan hydrogel loaded with bFGF (bFGF-hydrogel) was injected into a peri-infarcted area of cardiac tissue immediately following MI. Echocardiography demonstrated that the left ventricular functions were improved by the bFGF-hydrogel after 28 days of treatment. Histological results revealed that the hydrogel significantly reduced the fibrotic area of MI, and this was further improved by the bFGF-hydrogel treatment. TUNEL and immunohistochemical staining results showed that the bFGF-hydrogel had a more synergistic effect on antiapoptosis and proangiogenesis than using either bFGF or the hydrogel alone.

PMID:35014648 | DOI:10.1039/d1tb01961a

Ann Clin Transl Neurol. 2022 Jan 10. doi: 10.1002/acn3.51491. Online ahead of print.

ABSTRACT

OBJECTIVE: Dual leucine zipper kinase (DLK), which regulates the c-Jun N-terminal kinase pathway involved in axon degeneration and apoptosis following neuronal injury, is a potential therapeutic target in amyotrophic lateral sclerosis (ALS). This first-in-human study investigated safety, tolerability, and pharmacokinetics (PK) of oral GDC-0134, a small-molecule DLK inhibitor. Plasma neurofilament light chain (NFL) levels were explored in GDC-0134-treated ALS patients and DLK conditional knockout (cKO) mice.

METHODS: The study included placebo-controlled, single and multiple ascending-dose (SAD; MAD) stages, and an open-label safety expansion (OLE) with adaptive dosing for up to 48 weeks.

RESULTS: Forty-nine patients were enrolled. GDC-0134 (up to 1200 mg daily) was well tolerated in the SAD and MAD stages, with no serious adverse events (SAEs). In the OLE, three study drug-related SAEs occurred: thrombocytopenia, dysesthesia (both Grade 3), and optic ischemic neuropathy (Grade 4); Grade ≤2 sensory neurological AEs led to dose reductions/discontinuations. GDC-0134 exposure was dose-proportional (median half-life = 84 h). Patients showed GDC-0134 exposure-dependent plasma NFL elevations; DLK cKO mice also exhibited plasma NFL compared to wild-type littermates.

INTERPRETATION: This trial characterized GDC-0134 safety and PK, but no adequately tolerated dose was identified. NFL elevations in GDC-0134-treated patients and DLK cKO mice raised questions about interpretation of biomarkers affected by both disease and on-target drug effects. The safety profile of GDC-0134 was considered unacceptable and led to discontinuation of further drug development for ALS. Further work is necessary to understand relationships between neuroprotective and potentially therapeutic effects of DLK knockout/inhibition and NFL changes in patients with ALS.

PMID:35014217 | DOI:10.1002/acn3.51491

Transl Psychiatry. 2022 Jan 10;12(1):13. doi: 10.1038/s41398-021-01778-w.

ABSTRACT

Antipsychotic pharmacotherapy has been widely recommended as the standard of care for the treatment of acute schizophrenia and psychotic symptoms of other psychiatric disorders. However, there are growing concerns regarding antipsychotic-induced side effects, including weight gain, metabolic syndrome (MetS), and extrapyramidal motor disorders, which not only decrease patient compliance, but also predispose to diabetes and cardiovascular diseases. To date, most studies and reviews on the mechanisms of antipsychotic-induced metabolic side effects have focused on central nervous system mediation of appetite and food intake. However, disturbance in glucose and lipid metabolism, and hepatic steatosis induced by antipsychotic drugs might precede weight gain and MetS. Recent studies have demonstrated that the mechanistic/mammalian target of rapamycin (mTOR) pathway plays a critical regulatory role in the pathophysiology of antipsychotic drug-induced disorders of hepatic glucose and lipid metabolism. Furthermore, antipsychotic drugs promote striatal mTOR pathway activation that contributes to extrapyramidal motor side effects. Although recent findings have advanced the understanding of the role of the mTOR pathway in antipsychotic-induced side effects, few reviews have been conducted on this emerging topic. In this review, we synthesize key findings by focusing on the roles of the hepatic and striatal mTOR pathways in the pathogenesis of metabolic and extrapyramidal side effects, respectively. We further discuss the potential therapeutic benefits of normalizing excessive mTOR pathway activation with mTOR specific inhibitors. A deeper understanding of pathogenesis may inform future intervention strategies using the pharmacological or genetic inhibitors of mTOR to prevent and manage antipsychotic-induced side effects.

PMID:35013125 | DOI:10.1038/s41398-021-01778-w

Clin Oncol (R Coll Radiol). 2022 Jan 7:S0936-6555(21)00491-X. doi: 10.1016/j.clon.2021.12.010. Online ahead of print.

ABSTRACT

AIMS: To evaluate the efficacy and safety of nintedanib plus docetaxel in patients with advanced adenocarcinoma non-small cell lung cancer (NSCLC) who progressed after chemotherapy and immune checkpoint inhibitor (ICI) therapy.

MATERIALS AND METHODS: VARGADO (NCT02392455) is an ongoing, prospective, non-interventional, real-world study of nintedanib plus docetaxel after first-line chemotherapy in the routine clinical treatment of patients with locally advanced, metastatic or locally recurrent adenocarcinoma NSCLC. Data were collected during routine visits. We report the results from cohort B (n = 80), who received third-line nintedanib plus docetaxel after first-line chemotherapy and second-line ICI therapy.

RESULTS: The median duration of follow-up was 12.4 months. Median progression-free survival from initiation of third-line nintedanib plus docetaxel was 6.4 months (95% confidence interval 4.8, 7.3); median overall survival was 12.1 months (95% confidence interval 9.4, 13.5). The 1-year overall survival rate after initiation of third-line nintedanib plus docetaxel treatment (primary end point) was 52% (95% confidence interval 38.0%, 64.4%). Among 64 patients with a documented response, the objective response rate was 50% (n = 32; one complete response and 31 partial responses) and the disease control rate was 86% (n = 55). There were no new safety signals or unexpected toxicities. Among all treated patients, 74% (n = 59) experienced drug-related adverse events, most commonly (nintedanib-related/docetaxel-related) diarrhoea (34%/24%), a decreased white blood cell count (11%/19%) and nausea (13%/16%).

CONCLUSIONS: Nintedanib plus docetaxel demonstrated a high response rate and disease stabilisation in the third-line setting after failure of prior chemotherapy and ICI treatment, with a manageable safety profile. These results suggest that nintedanib plus docetaxel represents an efficient treatment option after failure of prior ICIs. The ongoing VARGADO study provides valuable real-world data to inform clinical decision-making regarding treatment sequencing after chemotherapy and ICI failure in patients with adenocarcinoma NSCLC.

PMID:35012901 | DOI:10.1016/j.clon.2021.12.010

J Clin Med. 2021 Dec 31;11(1):218. doi: 10.3390/jcm11010218.

ABSTRACT

BACKGROUND: Sclerobanding is a novel technique combining rubber band ligation with 3% polidocanol foam sclerotherapy for the treatment of hemorrhoidal disease (HD). The aim of this study is to evaluate the feasibility, safety and short-term outcomes of sclerobanding in the treatment of second- and third-degree HD.

METHODS: A retrospective analysis of second- and third-degree HD cases from November 2017 to August 2021 was performed. Patients on anticoagulants or with other HD degrees were excluded. Follow-up was conducted at 1 month, 3 months, 6 months, 1 year and then every 12 months.

RESULTS: 97 patients with second- (20 pts; 20.6%) and third-degree (77 pts; 79.4%) HD with a mean age of 52 years (20-84; SD ± 15.5) were included. Fifty-six patients were men (57.7%) and forty-one women (42.3%). Median follow-up was 13 months (1-26 months). No intraoperative adverse events or drug-related side effects occurred. Minor complications occurred in four patients (4.1%) in the first 30 postoperative days and all resolved after conservative treatment at the 3-month follow-up visit. No mortality or readmissions were observed.

CONCLUSIONS: Sclerobanding is a safe technique with a low rate of minor postoperative complications. Further studies on larger samples are necessary to establish the effectiveness and long-term outcomes of the technique.

PMID:35011962 | DOI:10.3390/jcm11010218

Molecules. 2021 Dec 30;27(1):226. doi: 10.3390/molecules27010226.

ABSTRACT

The drugs used to treat cancer not only kill fast-growing cancer cells, but also kill or slow the growth of healthy cells, causing systemic toxicities that lead to altered functioning of normal cells. Most chemotherapeutic agents have serious toxicities associated with their use, necessitating extreme caution and attention. There is a growing interest in herbal remedies because of their pharmacological activities, minimal side effects, and low cost. Thymoquinone, a major component of the volatile oil of Nigella sativa Linn, also known as black cumin or black seeds, is commonly used in Middle Eastern countries as a condiment. It is also utilized for medicinal purposes and possesses antidiabetic, anti-cancer, anti-inflammatory, hepatoprotective, anti-microbial, immunomodulatory, and antioxidant properties. This review attempts to compile the published literature demonstrating thymoquinone's protective effect against chemotherapeutic drug-induced toxicities.

PMID:35011457 | DOI:10.3390/molecules27010226

Int J Mol Sci. 2021 Dec 29;23(1):361. doi: 10.3390/ijms23010361.

ABSTRACT

Over half of older patients with acute myeloid leukemia (AML) do not respond to cytotoxic chemotherapy, and most responders relapse because of drug resistance. Cytarabine is the main drug used for the treatment of AML. Intensive treatment with high-dose cytarabine can increase the overall survival rate and reduce the relapse rate, but it also increases the likelihood of drug-related side effects. To optimize cytarabine treatment, understanding the mechanism underlying cytarabine resistance in leukemia is necessary. In this study, the gene expression profiles of parental HL60 cells and cytarabine-resistant HL60 (R-HL60) cells were compared through gene expression arrays. Then, the differential gene expression between parental HL60 and R-HL60 cells was measured using KEGG software. The expression of numerous genes associated with the nuclear factor κB (NF-κB) signaling pathway changed during the development of cytarabine resistance. Proteasome inhibitors inhibited the activity of non-canonical NF-κB signaling pathway and induced the apoptosis of R-HL60 cells. The study results support the application and possible mechanism of proteasome inhibitors in patients with relapsed or refractory leukemia.

PMID:35008789 | DOI:10.3390/ijms23010361

J Med Toxicol. 2022 Jan;18(1):67-68. doi: 10.1007/s13181-021-00872-1. Epub 2022 Jan 10.

NO ABSTRACT

PMID:35006548 | PMC:PMC8758848 | DOI:10.1007/s13181-021-00872-1

J Med Toxicol. 2022 Jan;18(1):65-66. doi: 10.1007/s13181-021-00871-2. Epub 2022 Jan 10.

NO ABSTRACT

PMID:35006546 | PMC:PMC8758859 | DOI:10.1007/s13181-021-00871-2

World J Clin Cases. 2021 Dec 6;9(34):10595-10603. doi: 10.12998/wjcc.v9.i34.10595.

ABSTRACT

BACKGROUND: Sedation with propofol injections is associated with a risk of addiction, but remimazolam benzenesulfonate is a comparable anesthetic with a short elimination half-life and independence from cell P450 enzyme metabolism. Compared to remimazolam, remimazolam benzenesulfonate has a faster effect, is more quickly metabolized, produces inactive metabolites and has weak drug interactions. Thus, remimazolam benzenesulfonate has good effectiveness and safety for diagnostic and operational sedation.

AIM: To investigate the clinical value of remimazolam benzenesulfonate in cardiac surgery patients under general anesthesia.

METHODS: A total of 80 patients who underwent surgery in the Department of Cardiothoracic Surgery from August 2020 to April 2021 were included in the study. Using a random number table, patients were divided into two anesthesia induction groups of 40 patients each: remimazolam (0.3 mg/kg remimazolam benzenesulfonate) and propofol (1.5 mg/kg propofol). Hemodynamic parameters, inflammatory stress response indices, respiratory function indices, perioperative indices and adverse reactions in the two groups were monitored over time for comparison.

RESULTS: At pre-anesthesia induction, the remimazolam and propofol groups did not differ regarding heart rate, mean arterial pressure, cardiac index or volume per wave index. After endotracheal intubation and when the sternum was cut off, mean arterial pressure and volume per wave index were significantly higher in the remimazolam group than in the propofol group (P < 0.05). After endotracheal intubation, the oxygenation index and the respiratory index did not differ between the groups. After endotracheal intubation and when the sternum was cut off, the oxygenation index values were significantly higher in the remimazolam group than in the propofol group (P < 0.05). Serum interleukin-6 and tumor necrosis factor-α levels 12 h after surgery were significantly higher than before surgery in both groups (P < 0.05). The observation indices were re-examined 2 h after surgery, and the epinephrine, cortisol and blood glucose levels were significantly higher in the remimazolam group than in the propofol group (P < 0.05). The recovery and extubation times were significantly lower in the remimazolam group than in the propofol group (P < 0.05); there were significantly fewer adverse reactions in the remimazolam group (10.00%) than in the propofol group (30.00%; P < 0.05).

CONCLUSION: Compared with propofol, remimazolam benzenesulfonate benefited cardiac surgery patients under general anesthesia by reducing hemodynamic fluctuations. Remimazolam benzenesulfonate influenced the surgical stress response and respiratory function, thereby reducing anesthesia-related adverse reactions.

PMID:35004991 | PMC:PMC8686148 | DOI:10.12998/wjcc.v9.i34.10595

Therapie. 2021 Dec 24:S0040-5957(21)00266-3. doi: 10.1016/j.therap.2021.12.014. Online ahead of print.

ABSTRACT

BACKGROUND AND PURPOSE: The EREMI project was set up to collect data on adverse drug reactions (ADRs) occurring due to off-label and/or unlicensed drugs prescribed to hospitalised children in France. These events were evaluated by a regional pharmacovigilance centre (RPC) and an adjudication committee (AC). The aim of this study was to assess the agreement between these two different entities on their evaluation of ADRs.

EXPERIMENTAL APPROACH: The RPC first validated the ADRs and assessed their causality using the Naranjo scale. The AC assessed then ADRs using all available information, including the RPC evaluation. The agreement on severity and nature of ADRs, role of treatment (suspect or concomitant) and drug causality was calculated using Cohen's nonparametric kappa coefficient (k).

KEY RESULTS: Three hundred and eighty-six events were reported in 219 children. The RPC excluded 65 events and validated 321 ADRs. Agreement was very good on nature of ADRs (k=0.85) and role of treatment (k=0.81), moderate on severity of ADRs (k=0.60) and very poor on drug causality (k=0.05).

CONCLUSION AND IMPLICATIONS: Agreement between the RPC and the AC was not constant throughout this evaluation. They troubled to agree on severe ADRs and on drug causality.

PMID:34998623 | DOI:10.1016/j.therap.2021.12.014

Circulation. 2022 Jan 25;145(4):299-308. doi: 10.1161/CIRCULATIONAHA.121.054883. Epub 2022 Jan 7.

ABSTRACT

BACKGROUND: Multiple reports associate the cardiac sodium channel gene (SCN5A) variants S1103Y and R1193Q with type 3 congenital long QT syndrome and drug-induced long QT syndrome. These variants are too common in ancestral populations to be highly arrhythmogenic at baseline, however: S1103Y allele frequency is 8.1% in African Americans and R1193Q 6.1% in East Asians. R1193Q is known to increase late sodium current (INa-L) in cardiomyocytes derived from induced pluripotent stem cells but the role of these variants in modulating repolarization remains poorly understood.

METHODS: We determined the effect of S1103Y on QT intervals among African-American participants in a large electronic health record. Using cardiomyocytes derived from induced pluripotent stem cells carrying naturally occurring or genome-edited variants, we studied action potential durations (APDs) at baseline and after challenge with the repolarizing potassium current (IKr) blocker dofetilide and INa-L and IKr at baseline.

RESULTS: In 1479 African-American participants with no confounding medications or diagnoses of heart disease, QT intervals in S1103Y carriers was no different from that in noncarriers. Baseline APD was no different in cells expressing the Y allele (SY, YY cells) compared with isogenic cells with the reference allele (SS cells). However, INa-L was increased in SY and YY cells and the INa-L blocker GS967 shortened APD in SY/YY but not SS cells (P<0.001). IKr was increased almost 2-fold in SY/YY cells compared with SS cells (tail current: 0.66±0.1 versus 1.2±0.1 pA/pF; P<0.001). Dofetilide challenge prolonged APD at much lower concentrations in SY (4.1 nmol/L [interquartile range, 1.5-9.3]; n=11) and YY (4.2 nmol/L [1.7-5.0]; n=5) than in SS cells (249 nmol/L [22.3-2905]; n=14; P<0.001 and P<0.01, respectively) and elicited afterdepolarizations in 8/16 SY/YY cells but only in 1/14 SS cells. R1193Q cells similarly displayed no difference in baseline APD but increased IKr and increased dofetilide sensitivity.

CONCLUSIONS: These common ancestry-specific variants do not affect baseline repolarization, despite generating increased INa-L. We propose that increased IKr serves to maintain normal repolarization but increases the risk of manifest QT prolongation with IKr block in variant carriers. Our findings emphasize the need for inclusion of diverse populations in the study of adverse drug reactions.

PMID:34994586 | DOI:10.1161/CIRCULATIONAHA.121.054883