A Cost-Effective and Labor-Saving Method for Detecting Human Leukocyte Antigen B27 Status via Sequence-Encoded Fluorescence Amplification Assay.

Identification of human leukocyte antigen B27 (HLA-B27) by flow cytometry (FCM) has been widely applied in clinical practice for auxiliary diagnosis of ankylosing spondylitis (AS). However, FCM requires freshly prepared samples and relies on expensive equipment, reagents, and an experienced operator. To provide a cheaper and more convenient method for HLA-B27 detection, we proposed a new method termed sequence-encoded fluorescence amplification assay (SEFA), which specially recognized sequences of HLA-B27 gene (HLA-B∗27) covering current common subtypes in a single closed tube. SEFA could detect as low as 10 pg (equal to 3 copies) genomic DNA per reaction and distinguish HLA-B∗27 from other HLA-B alleles with highly similar sequences. A total of 288 clinical samples were tested by SEFA, including 181 patients with AS and 107 healthy controls. Compared with the detection results from FCM, two controversial samples of patients with AS were obtained and further confirmed to be consistent with SEFA by Sanger sequencing, indicating that our method was more accurate than FCM. Moreover, SEFA could detect HLA-B27 status by using supernatant from crude extract of 10-µL blood without commercial reagents. Overall, SEFA has the potential to be an alternative for HLA-B27 identification with the advantage of convenience and low cost, especially suitable for early diagnosis of AS in areas with limited medical resources.

CircXRN2 accelerates colorectal cancer progression through regulating miR-149-5p/MACC1 axis and EMT.

In China, there has been a persistent upward trend in the incidence and mortality rates of colorectal cancer (CRC), with CRC ranking second in incidence and fifth in mortality among all malignant tumors. Although circular RNAs (circRNAs) have been implicated in the progression of various cancers, their specific role in CRC progression remains largely unexplored. The objective of this study was to elucidate the role and underlying mechanisms of circXRN2 in CRC. Differential expression of circXRN2 was identified through whole transcriptome sequencing. The expression levels of circXRN2 and miR-149-5p were quantified in CRC tissues, corresponding adjacent normal tissues, and CRC cell lines using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The stability of circXRN2 was confirmed through RNase R and actinomycin D experiments. The binding interaction between circXRN2 and miR-149-5p was validated through RNA pull-down, RNA immunoprecipitation, and dual-luciferase assays. The biological functions of circXRN2 were assessed through a battery of in vitro experiments, including the CCK-8 assay, EdU assay, scratch assay, Transwell assay, and flow cytometry assay. Additionally, in vivo experiments involving a tumor transplantation model and a liver-lung metastasis model were conducted. The influence of circXRN2 on the expression of epithelial-mesenchymal transition (EMT)-related genes was determined via Western blotting analysis. In CRC tissues and cells, there was an upregulation in the expression levels of both circXRN2 and ENC1, while miR-149-5p exhibited a downregulation in its expression. The overexpression of circXRN2 was found to enhance tumor proliferation and metastasis, as evidenced by results from both in vitro and in vivo experiments. Functionally, circXRN2 exerted its antitumor effect by suppressing cell proliferation, migration, and invasion while also promoting apoptosis. Mechanistically, the dysregulated expression of circXRN2 had an impact on the expression of proteins within the EMT signaling pathway. Our results demonstrated that circXRN2 promoted the proliferation and metastasis of CRC cells through the miR-149-5p/ENC1/EMT axis, suggesting that circXRN2 might serve as a potential therapeutic target and novel biomarker in the progression of CRC.

Meta-analysis of the efficacy and safety of Ginkgolide Meglumine Injection combined with Butylphthalide in the treatment of Acute Ischemic Stroke.

OBJECTIVE: To evaluate the efficacy and safety of Ginkgolide Meglumine Injection (GMI) combined with Butylphthalide in the treatment of Acute Ischemic Stroke (AIS), and provide reference for rational clinical medication. METHODS: PubMed, Embase, Web of science, CNKI, Wanfang, VIP and other databases were searched for published studies on the treatment of AIS with GMI combined with Butylphthalide in both Chinese and English. The search period was from the establishment of the database to July 2023. The included studies that met the inclusion criteria were analyzed using RevMan 5.3 software for Meta-analysis. RESULTS: A total of 25 studies involving 2362 patients (experimental group = 1182, control group = 1180) were included. The results of meta-analysis showed that the overall effective rate of the experimental group was significantly higher than that of the control group [RR = 1.21, 95% CI (1.16, 1.26), P< 0.00001]. In addition, compared with the control group, the experimental group showed significant improvement in NIHSS score [SMD = -1.59, % CI (-2.00-1.18), P< 0.00001] and ADL score [SMD = 2.12, 95% CI (1.52, -2.72), P<0.00001], significant decrease in CRP [SMD = -2.24, 95% CI (-3.31, -1.18), P<0.0001] and TNF-α [SMD = -2.74, 95% CI (-4.45, -1.03), P< 0.005] levels, and improvement in plasma viscosity [SMD = -0.86, 95% CI (-1.07, -0.66), P< 0.00001]. However, the influence on homocysteine level remains inconclusive. Furthermore, there was no significant difference in the incidence of adverse reactions between the two groups [SMD = 0.95, 95% CI (0.71, 1.28), P> 0.05]. CONCLUSION: GMI combined with Butylphthalide shows good clinical application effects and good safety in the treatment of AIS. However, more large-sample, multicenter, randomized controlled are needed to confirm these findings.

Meta-analysis of the effectiveness and safety of Xingnaojing and naloxone in the treatment of carbon monoxide poisoning.

BACKGROUND: To evaluate the effectiveness and safety of Xingnaojing combined with naloxone in the treatment of carbon monoxide poisoning. METHODS: By retrieving the literatures published in the databases of PubMed, Cochrane Library, Web of Science, Embase, Wanfang Database, Weipu Database, and China National Knowledge Infrastructure from January 2010 to September 2021, the data of randomized controlled trials (RCTs) of Xingnaojing combined with naloxone in the treatment of carbon monoxide poisoning were extracted. The methodological quality of the included RCTs was evaluated by using the tools of bias risk evaluation of Cochrane Collaboration, and the data were statistically analyzed by using RevMan 5.3 software. RESULTS: A total of 20 literatures were included, involving in 771 cases treated by Xingnaojing combined with naloxone and 761 cases in the control group. The effective rate of the experimental group is higher than that of the control group [risk ratio (RR) = 1.20, 95% confidence interval (CI) (1.14, 1.26)]. The average awake time (STD mean difference = -2.08, 95% CI [-2.60, -1.56]), physical recovery time (STD mean difference = -2.94, 95% CI [-3.59, -2.28]), delayed encephalopathy (RR = 0.44, 95% CI [0.31, 0.62]), and adverse reactions (RR = 0.23, 95% CI [0.10, 0.54]) was lower than that of the control group. CONCLUSION: Xingnaojing combined with naloxone in the treatment of carbon monoxide poisoning is significantly superior to naloxone, but it still needs to be further verified by high-quality large samples of RCTs.

Right hemicolectomy combined with duodenum-jejunum Roux-en-Y anastomosis for hepatic colon carcinoma invading the duodenum: A single-center case series.

BACKGROUND: Hepatic colon carcinoma invading the duodenum is not common in clinical practice. Surgical treatment of colonic hepatic cancer that invades the duodenum is difficult, and the surgical risk is high. AIM: To discuss the efficacy and safety of duodenum-jejunum Roux-en-Y anastomosis for the treatment of hepatic colon carcinoma invading the duodenum. METHODS: From 2016 to 2020, 11 patients from Panzhihua Central Hospital diagnosed with hepatic colon carcinoma were enrolled in this study. Clinical and therapeutic effects and prognostic indicators were retrospectively analyzed to determine the efficacy and safety of our surgical procedures. All patients underwent radical resection of right colon cancer combined with duodenum-jejunum Roux-en-Y anastomosis. RESULTS: The median tumor size was 65 mm (r50-90). Major complications (Clavien-DindoI-II) occurred in 3 patients (27.3%); the average length of hospital stay was 18.09 ± 4.21 d; and only 1 patient (9.1%) was readmitted during the 1st mo after the surgery. The 30-d mortality rate was 0%. After a median follow-up of 41 m (r7-58), the disease-free survival at 1, 2, and 3 years was 90.9%, 90.9% and 75.8%, respectively; the overall survival at 1, 2, and 3 years was 90.9%. CONCLUSION: In selected patients, radical resection of right colon cancer combined with duodenum-jejunum Roux-en-Y anastomosis is clinically effective, and the complications are manageable. The surgical procedure also has an acceptable morbidity rate and mid-term survival.

Cannabidiol inhibits invasion and metastasis in colorectal cancer cells by reversing epithelial-mesenchymal transition through the Wnt/ß-catenin signaling pathway.

Colorectal cancer (CRC) is the leading cause of cancer deaths worldwide, wherein distant metastasis is the main reason for death. The non-psychoactive phytocannabinoid cannabidiol (CBD) effectively induces the apoptosis of CRC cells. We investigated the role of CBD in the migration and metastasis of CRC cells. CBD significantly inhibited proliferation, migration, and invasion of colon cancer cells in a dose- or time-dependent manner. CBD could also inhibit epithelial-mesenchymal transition (EMT) by upregulating epithelial markers such as E-cadherin and downregulating mesenchymal markers such as N-cadherin, Snail, Vimentin, and HIF-1α. CBD could suppress the activation of the Wnt/ß-catenin signaling pathway, inhibit the expression of ß-catenin target genes such as APC and CK1, and increase the expression of Axin1. Compared to the control group, the volume and weight of orthotopic xenograft tumors significantly decreased after the CBD treatment. The results demonstrated that CBD inhibits invasion and metastasis in CRC cells. This was the first study elucidating the underlying molecular mechanism of CBD in inhibiting EMT and metastasis via the Wnt/ß-catenin signaling pathway in CRC cells. The molecular mechanism by which CBD inhibits EMT and metastasis of CRC cells was shown to be through the Wnt/ß-catenin signaling pathway for the first time.

TGFß1 induces myofibroblast transdifferentiation via increasing Smad-mediated RhoGDI-RhoGTPase signaling.

This study serves to investigate the effects of the Smad pathway on TGFß1-mediated RhoGDI expression and its binding to RhoGTPases in myofibroblast transdifferentiation. Myofibroblast transdifferentiation was induced by TGFß1 in vitro. Cells were pretreated with different siRNAs or inhibitors. Myofibroblast transdifferentiation was detected by immunohistochemistry. Immunofluorescence was used to observe the nuclear translocation of Smad4, and PSR (Picrositius Red) staining was used to measure collagen concentration. TGFß1 induced the phosphorylation of Smad2/3 and the nuclear translocation of Smad4 in human aortic adventitial fibroblasts (HAAFs). Furthermore, TGFß1 increased the expression of RhoGDI and its binding to RhoGTPases. Nevertheless, inhibition of Smad2/3 phosphorylation decreased TGFß1-induced RhoGDI1/2 expressions and RhoGDI2-RhoGTPases interactions. These data suggested that the inhibition of Smad phosphorylation attenuates myofibroblast transdifferentiation by inhibiting TGFß1-induced RhoGDI1/2 expressions and RhoGDI-RhoGTPases signaling.

Rectal cancer combined with abdominal tuberculosis: A case report.

BACKGROUND: It is very rare to suffer from colorectal adenocarcinoma and abdominal tuberculosis simultaneously. Even in a country such as China, where tuberculosis is still endemic, its diagnosis and treatment are challenging. This article describes in detail a case of rectal cancer complicated by abdominal tuberculosis and its pathological features. CASE SUMMARY: We outline the case of a 71-year-old female who was admitted with intermittent blood in the stool over the past year. The patient was diagnosed with low rectal cancer and received neoadjuvant therapy. The patient then returned to the hospital for surgery, but diffusely distributed nodules were found during laparoscopic exploration. The diagnosis of rectal cancer with extensive metastasis was considered during the operation. There was no opportunity for radical surgery. Thus, nodules were taken for pathological examination, and the abdomen was closed. The histopathological diagnosis was tuberculous granuloma, and the patient was treated with standardized anti-tuberculosis drugs in a specialized hospital. Later, the patient again came to our hospital and underwent abdominoperineal resection. She was discharged 10 d after the operation in good clinical condition. CONCLUSION: We aim to emphasize the importance of preoperative and postoperative pathological examination in diagnosis and treatment.

Meta-analysis of the effectiveness and safety of Shenyankangfu tablets combined with losartan potassium in the treatment of chronic glomerulonephritis.

OBJECTIVE: To conduct a systematic review of the efficacy and safety of Shenyankangfu tablets in combination with losartan potassium in the treatment of chronic glomerulonephritis. METHOD: We searched PubMed, Embase, Cochrane Library, CNKI, WanFang Data, and WeiPu for comparative studies on Shenyankangfu tablets in combination with losartan potassium in the treatment of chronic glomerulonephritis. The search period runs from the establishment of the database until September 2021. Data extraction and quality evaluation were carried out on the documents that met the inclusion criteria, and a meta-analysis of the included literature was conducted using the RevMan5.3 software. RESULTS: A total of 17 randomized controlled trials that met the inclusion criteria were included, with a total sample size of 1680 patients (841 patients in the study group and 839 in the control group). The effective rate was significantly higher in the study group than in the control group [RR = 1.22, 95% CI (1.16, 1.27), P < 0.00001]. In addition, 24-hour urine protein levels [SMD = -1.11, 95% CI (-1.40, -0.83), P < 0.00001], urine NAG enzyme [SMD = -0.99, 95% CI (-1.27, -0.72), P < 0.00001], leukotactin-1 [SMD = -2.43, 95% CI (-3.50, -1.35), P < 0.00001], and the incidence of adverse reactions [RR = 0.43, 95% CI (0.28, 0.66), P < 0.00001] were lower in the study group when compared to the control group. CONCLUSION: It is safer to treat chronic glomerulonephritis with Shyenyankangfu tablets in combination with losartan potassium. At the same time, it alleviates disease-related symptoms, reduces the influence of cytokine levels, and has fewer adverse reactions, making it more conducive to disease recovery. However, additional multi-center, randomized, control trials with large sample sizes must be conducted to confirm the findings.

Customized Multifunctional Peptide Hydrogel Scaffolds for CAR-T-Cell Rapid Proliferation and Solid Tumor Immunotherapy.

CAR-T-cell therapies must be expanded to obtain a large number of effector cells quickly, and the current technology cannot address this challenge. A longer operational time would lose or alter the function and phenotype of CAR-T cells in response to therapy, and it also causes a loss in the optimal treatment time for patients. At present, lower survival time and homing efficiency reduce the antitumor effect of CAR-T in vivo. But nobody has solved these two issues in one system, which has a similar microenvironment of lymphoid organs to activate/expand cell delivery for immunotherapy. Here, we generated artificial, customized immune cell matrix scaffolds based on a self-assembling peptide to preserve and augment the cell phenotype in light of the characteristics of CAR-T. The all-in-one nanoscale matrix scaffolds reduced the processing time of CAR-T to 3 days and resulted in over a 10-fold increase compared with the traditional protocol. The cells were combined to modulate mechanotransduction and chemical signals, and the mimic matrix scaffolds showed optimal stiffness and adhesive ligand density, thereby accelerating CAR-T-cell proliferation. Meanwhile, engineering CAR-T-secreted intrinsic PD-1 blocking single-chain variable fragments (scFv) further increased cell proliferation and cytotoxicity by resisting the self and tumor microenvironment in a paracrine and autocrine manner. Local delivery of CAR-T cells from the scaffolds significantly enabled long-term retention, suppressed tumor growth, and increased infiltration of effector T cells compared with traditional CAR-T treatment. The application of bioengineering and genetic engineering approaches has led to the development of rapid culture environments that can control matrix scaffold properties for CAR-T-cell and cancer immunotherapies.

Immune Cell-Derived Extracellular Vesicles - New Strategies in Cancer Immunotherapy.

Immune cell-derived extracellular vesicles (EVs) have increasingly become the focus of research due to their unique characteristics and bioinspired applications. They are lipid bilayer membrane nanosized vesicles harboring a range of immune cell-derived surface receptors and effector molecules from parental cells. Immune cell-derived EVs are important mediators of intercellular communication that regulate specific mechanisms of adaptive and innate immune responses. However, the mechanisms underlying the antitumor effects of EVs are still being explored. Importantly, immune cell-derived EVs have some unique features, including accessibility, storage, ability to pass through blood-brain and blood-tumor barriers, and loading of various effector molecules. Immune cell-derived EVs have been directly applied or engineered as potent antitumor vaccines or for the diagnosis of clinical diseases. More research applications involving genetic engineering, membrane engineering, and cargo delivery strategies have improved the treatment efficacy of EVs. Immune cell-derived EV-based therapies are expected to become a separate technique or to complement immunotherapy, radiotherapy, chemotherapy and other therapeutic modalities. This review aims to provide a comprehensive overview of the characteristics and functions of immune cell-derived EVs derived from adaptive (CD4+ T, CD8+ T and B cells) and innate immune cells (macrophages, NK cells, DCs, and neutrophils) and discuss emerging therapeutic opportunities and prospects in cancer treatment.

The Intracellular Mechanism of Berberine-Induced Inhibition of CYP3A4 Activity.

BACKGROUND: Berberine (BBR) is an isoquinoline alkaloid extracted from the Chinese medicine, exerting a variety of pharmacological effects. BBR is partially metabolized by cytochrome 3A4 (CYP3A4) in vivo. Some reports indicated that BBR could inhibit the activity of CYP3A4. However, the underlying mechanisms are not completely understood. CYP3A4 is reported to be transcriptionally regulated by two nuclear receptors, nuclear transcription X receptor (PXR) and constitutive androstane receptor (CAR), and degraded via the ubiquitin-proteasome system. Hence, we tried to explore the mechanisms of CYP3A4 inhibition on both transcriptive and protein levels. METHODS: Western Blot, RT-PCR and Co-immunoprecipitation were used to perform the experiments. RESULTS: Our results showed that BBR inhibited the transcription of CYP3A4 gene by downregulating PXR. In addition, BBR accelerated the degradation of CYP3A4 protein via polyubiquitination pathway. CONCLUSION: These findings may lead to the determination of novel drug-drug interactions with BBR, and contribute to future clinical application of BBR.

The exosomes derived from CAR-T cell efficiently target mesothelin and reduce triple-negative breast cancer growth.

Genetically engineered T cells expressing a chimeric antigen receptor (CAR) have rapidly developed into a powerful and innovative therapeutic modality for cancer patients. However, the problem of dose-dependent systemic toxicity cannot be ignored. In this study, exosomes derived from mesothelin (MSLN)-targeted CAR-T cells were isolated, and we found that they maintain most characteristics of the parental T cells, including surface expression of the CARs and CD3. Furthermore, CAR-carrying exosomes significantly inhibited the growth of both endogenous and exogenous MSLN-positive triple-negative breast cancer (TNBC) cells. The expression of the effector molecules perforin and granzyme B may be a mechanism of tumor killing. More importantly, a highly effective tumor inhibition rate without obvious side effects was observed with the administration of CAR-T cell exosomes in vivo. Thus, the use of CAR-T cell exosomes has great therapeutic potential against MSLN-expressing TNBC.

The Prevention and Inhibition Effect of Anthocyanins on Colorectal Cancer.

BACKGROUND: Anthocyanins are a type of flavonoids that are natural water soluble glycosidic pigments with efficacious anti-cancer effects, which have good biological activity against many cancers including colorectal cancer (CRC). However, the exact molecular mechanism used by anthocyanins against cancer is unclear; it is also unclear what a reasonable dosage might be for their use against colorectal cancer. METHODS: Western blotting, immunohistochemistry, MTT assay, xenograft model, and hematoxylin-eosin (HE) staining were used to perform the experiments. RESULTS: Compared with the control group, anthocyanins could significantly inhibit the cell viability and proliferation and promote the apoptosis of human colon cancer HT29 cells. Furthermore, anthocyanins reduced tumor weight and volume in a colon tumor mouse model and downregulated the expression of PI3K protein, inhibited AKT expression and phosphorylation, decreased the Bcl-2 and Bax ratio and reduced survivin protein expression in the tumor tissue. CONCLUSION: Anthocyanins promoted apoptosis of CRC cells and inhibited colon cancer growth of xenografted tumors. Mechanistically, anthocyanins enhanced the Bcl-2/Bax and caspase-dependent apoptotic pathways through targeting the PI3K/AKT/survivin pathway, resulting in impairment of growth of CRC.

Intracellular Mechanism of Rosuvastatin-Induced Decrease in Mature hERG Protein Expression on Membrane.

The hERG potassium channel (IKr) encoded by human ether-a-go-go-related gene plays an important role in cardiac repolarization. Decreased IKr may lead to long QT syndrome, which subsequently causes torsade de pointes and sudden cardiac death. Previous studies have shown that statins inhibit IKr and are more potent in inhibiting hERG currents when combined with other drugs. Since chemical structure of rosuvastatin is similar to that of several IKr blockers (ibutilide and E-4031), the present study aimed to reveal the mechanism that underlies rosuvastatin-induced hERG current reduction and to evaluate the possibility of cardiac toxicity. The results showed that rosuvastatin reduced hERG currents by accelerating the inactivation and prolonged action potential duration (APD) in hiPSC-CMs. Meanwhile, it was observed that rosuvastatin reduced the expression of the mature hERG. Transcription factor Sp1 was involved in hERG protein downregulation induced by rosuvastatin, and the result was verified by Sp1 siRNA and Sp1 agonist epicatechin. These results indicated that rosuvastatin could potentially inhibit transcription and reduce hERG mRNA expression. The interaction between hERG and heat shock protein was evaluated to study the mechanism of trafficking inhibition through co-immunoprecipitation. We found that rosuvastatin reduces the interaction of heat shock protein 70 (Hsp70) with the hERG protein, thereby affecting the folding of the hERG channel. Additionally, rosuvastatin significantly activates ATF6, which plays a key role in the activation of the unfolded protein response (UPR) pathway. Increased expression of the molecular chaperone calnexin and calreticulin, which are activated by ATF6 to help channel folding, further confirmed UPR activation. Meanwhile, the degradation of the hERG channel was mediated by lysosomes and proteasomes. In conclusion, Rosuvastatin reduced the expression of hERG plasma membrane by two pathways, the first is to disrupt the transport of immature hERG channels to the membrane, and the second is to increase the degradation of mature hERG channels. In addition, Rosuvastatin potently blocked hERG current, delayed cardiac repolarization, and thereby prolonged APDs and QTc intervals. Therefore, caution should be taken when rosuvastatin is used in the treatment of hyperlipidemia, especially when combined with drugs that can prolong the QT interval.

The enhancement of cardiotoxicity that results from inhibiton of CYP 3A4 activity and hERG channel by berberine in combination with statins.

Metabolism of most endogenous and exogenous compounds is usually produced by the oxidation of cytochrome P450. Due to drug-drug interactions caused by the inhibition or induction of cytochrome P450 enzymes, changes in drug metabolism are the major causes of drug toxicity, CYP3A4 is one of the key isozymes, and involved in the metabolism of over 60% of clinical drugs. Human ether-a-go-go related genes (hERG) potassium channel is the most important target of many drugs and plays an important role in cardiac repolarization. Blockade of this channel may lead to long QT syndrome (LQTS), leading to sudden cardiac death. Therefore, it is necessary to evaluate the inhibitory properties of drugs on cytochrome P450 enzymes and hERG channel. We primarily evaluate the safety of berberine in combination with statins. Based on these findings, berberine in combination with statins has a greater inhibitory effect on CYP3A4 activity and CYP3A4 protein and mRNA expression than berberine alone. Simvastatin and atorvastatin reduce hERG current by accelerating channel inactivation. At the same time, the inhibitory effect of berberine and statin combination increased on hERG current by reducing the time constant of inactivation than the single drug alone. These results indicate that berberine in combination with statins can increase cardiotoxicity by inhibiting CYP3A4 and hERG channel.

The enhancement of cardiac toxicity by concomitant administration of Berberine and macrolides.

As is well-known, hERG plays an essential role in phase III repolarization of cardiac action potentials. Blocking of hERG channels can lead to LQTS. Inhibition of the metabolism of CYPs activities may elevate plasma levels, to further increase accumulation of drug on cardiac. The elevated serum levels may however elicit unexpected toxicities. Therefore, the inhibition tests of hERG and CYP are central to the preclinical studies because they may lead to severe cardiac toxicity. Berberine is widely used as an antibacterial agent and often combined with macrolides to treat gastropathy. Our objective was to assess cardiac toxicity during the combined use of Berberine with macrolides. (1) Azithromycin reduced hERG currents by accelerated channel inactivation. (2) The combination of Berberine with Azithromycin reduced hERG currents, producing an inhibitive effect stronger than use of a single drug alone, due to the high binding affinity for the onset of inactivation. (3) When cells were perfused concomitantly with Berberine and Clarithromycin, they showed a stronger inhibitive effect on hERG currents by decreasing the time constant for the onset of inactivation. (4) The combined administration of Berberine with Clarithromycin had a powerful inhibitive effect on CYP3A activities than use of a single drug alone. Collectively, these results demonstrated that concomitant use of Berberine with macrolides may require close monitoring because of potential drug toxicities, especially cardiac toxicity.

Up-regulation of miR-21 and miR-23a Contributes to As2 O3 -induced hERG Channel Deficiency.

Arsenic trioxide (As2O3) is used to treat acute pro-myelocytic leukaemia. However, the cardiotoxicity of long QT syndrome restricts its clinical application. Previous studies showed that As2O3 can damage the hERG current via disturbing its trafficking to cellular membrane. Consistent with these findings, in this study, we reported that As2O3 inhibited hERG channel at both protein and mRNA levels and damaged hERG current but did not affect channel kinetics. Further, we demonstrated that As2O3 up-regulated miR-21 and miR-23a expression in hERG-HEK293 cells and neonatal cardiomyocytes. In addition, knock-down of miR-21 by its specific antisense molecules AMO-21 was able to rescue Sp1 and hERG inhibition caused by As2O3. Consistently, phosphorylation of NF-κB, the upstream regulatory factor of miR-21, was significantly up-regulated by As2O3 . This finding revealed that regulation of the NF-κB-miR-21-Sp1 signalling pathway is a novel mechanism for As2O3-induced hERG inhibition. Meanwhile, the expression of Hsp90 and hERG was rescued by transfection with AMO-23a. And the hERG channel inhibition induced by As2O3 was rescued after being transfected with AMO-23a, which may be a molecular mechanism for the role of As2O3 in hERG trafficking deficiency. In brief, our study revealed that miR-21 and miR-23a are involved in As2O3-induced hERG deficiency at transcriptional and transportational levels. This discovery may provide a novel mechanism of As2O3-induced hERG channel deficiency, and these miRNAs may serve as potential therapeutic targets for the handling of As2O3 cardiotoxicity.