Exosomes regulate doxorubicin resistance in breast cancer via miR-34a-5p/NOTCH1.

Breast cancer (BRCA) is the most common cancer among women. Adriamycin (ADR), also known as doxorubicin (Dox), is a commonly used chemotherapeutic agent for BRCA patients, however, the susceptibility of tumor cells to develop resistance to Dox has severely limited its clinical use. One new promising therapeutic target for breast cancer patients is exosomes. The objective of this study was to investigate the role of exosomes in regulating Dox resistance in BRCA. In this study, the exosomes from both types of cells were extracted by differential centrifugation. The effect of exosomes on drug resistance was assessed by laser confocal microscopy, MTT assay, and qRT-PCR. The miRNA was transfected into cells using Lipofectamine 2000, which was then evaluated for downstream genes and changes in drug resistance. Exosomes from MCF-7 cells (MCF-7/exo) and MCF-7/ADR cells (ADR/exo) were effectively extracted in this study. The ADR/exo was able to endocytose MCF-7 cells and make them considerably more resistant to Dox. Moreover, we observed a significant difference in miR-34a-5p expression in MCF-7/ADR and ADR/exo compared to MCF-7 and MCF-7/exo. Among the miR-34a-5p target genes, NOTCH1 displayed a clear change with a negative correlation. In addition, when miR-34a-5p expression was elevated in MCF-7/ADR cells, the expression of miR-34a-5p in ADR/exo was also enhanced alongside NOTCH1, implying that exosomes may carry miRNA into and out of cells and perform their function. In conclusion, exosomes can influence Dox resistance in breast cancer cells by regulating miR-34a-5p/NOTCH1. These findings provide novel insights for research into the causes of tumor resistance and the enhancement of chemotherapy efficacy in breast cancer.

Role of glutaminyl-peptide cyclotransferase in breast cancer doxorubicin sensitivity.

Doxorubicin (DOX) is one of the most effective and widely used chemotherapeutic drugs. However, DOX resistance is a critical risk problem for breast cancer treatment. Previous studies have demonstrated that metadherin (MTDH) involves in DOX resistance in breast cancer, but the exact mechanism remains unclear. In this study, we found that glutaminyl-peptide cyclotransferase (QPCT) was a MTDH DOX resistance-related downstream gene in breast cancer. Elevated expression of QPCT was found in the GEPIA database, breast cancer tissue, and breast cancer cells. Clinical data showed that QPCT expression was positively associated with poor prognosis in DOX-treated patients. Overexpression of QPCT could promote the proliferation, invasion and migration, and reduce DOX sensitivity in MCF-7 and MDA-MB-231 cells. Mechanistically, MTDH positively regulates the expressions of NF-κB (p65) and QPCT, and NF-κB (p65) directly regulates the expression of QPCT. Therefore, MTDH/NF-κB (p65)/QPCT signal axis was proposed. Collectively, our findings delineate the mechanism by which the MTDH/NF-κB (p65) axis regulate QPCT signaling and suggest that this complex may play an essential role in breast cancer progression and affect DOX sensitivity.

Doxorubicin resistance in breast cancer is mediated via the activation of FABP5/PPARγ and CaMKII signaling pathway.

Breast cancer is the most prevalent malignancy among women. Doxorubicin (Dox) resistance was one of the major obstacles to improving the clinical outcome of breast cancer patients. The purpose of this study was to investigate the relationship between the FABP signaling pathway and Dox resistance in breast cancer. The resistance property of MCF-7/ADR cells was evaluated employing CCK-8, Western blot (WB), and confocal microscopy techniques. The glycolipid metabolic properties of MCF-7 and MCF-7/ADR cells were identified using transmission electron microscopy, PAS, and Oil Red O staining. FABP5 and CaMKII expression levels were assessed through GEO and WB approaches. The intracellular calcium level was determined by flow cytometry. Clinical breast cancer patient's tumor tissues were evaluated by immunohistochemistry to determine FABP5 and p-CaMKII protein expression. In the presence or absence of FABP5 siRNA or the FABP5-specific inhibitor SBFI-26, Dox resistance was investigated utilizing CCK-8, WB, and colony formation methods, and intracellular calcium level was examined. The binding ability of Dox was explored by molecular docking analysis. The results indicated that the MCF-7/ADR cells we employed were Dox-resistant MCF-7 cells. FABP5 expression was considerably elevated in MCF-7/ADR cells compared to parent MCF-7 cells. FABP5 and p-CaMKII expression were increased in resistant patients than in sensitive individuals. Inhibition of the protein expression of FABP5 by siRNA or inhibitor increased Dox sensitivity in MCF-7/ADR cells and lowered intracellular calcium, PPARγ, and autophagy. Molecular docking results showed that FABP5 binds more powerfully to Dox than the known drug resistance-associated protein P-GP. In summary, the PPARγ and CaMKII axis mediated by FABP5 plays a crucial role in breast cancer chemoresistance. FABP5 is a potentially targetable protein and therapeutic biomarker for the treatment of Dox resistance in breast cancer.

Bradykinin receptor participates in doxorubicin-induced cardiotoxicity by modulating iNOS signal pathway.

Doxorubicin (DOX), an effective and broad-spectrum anthracycline antibiotic, is widely used in the treatment of numerous malignancies. However, dose-dependent cardiotoxicity limits the clinical application of DOX, and the molecular mechanisms are still unknown. In this study, we used the BK receptor B1/B2 double-knockout (B1B2 -/- ) mice to observe the role of BK receptor in cardiotoxicity induced by DOX and the underlying mechanisms. DOX induced myocardial injury with increased serum levels of AST, CK, and LDH, upregulated tissue expression of bradykinin B1/B2 receptor, FABP4 and iNOS, and downregulated expression of eNOS. However, these altered releases of myocardial enzyme and the expression level of iNOS were significantly prevented in the B1B2-/- mice. We concluded that the activation of both B1 and B2 receptors of BK were involved in the DOX-induced acute myocardial injury, possibly mediated through iNOS signaling pathways.

Antitumor Activity of Berberine by Activating Autophagy and Apoptosis in CAL-62 and BHT-101 Anaplastic Thyroid Carcinoma Cell Lines.

Introduction: Anaplastic thyroid carcinoma (ATC) is the most lethal thyroid carcinoma. Doxorubicin (DOX) is the only drug approved for anaplastic thyroid cancer treatment, but its clinical use is restricted due to irreversible tissue toxicity. Berberine (BER), an isoquinoline alkaloid extracted from Coptidis Rhizoma, has been proposed to have antitumor activity in many cancers. However, the underlying mechanisms by which BER regulates apoptosis and autophagy in ATC remain unclear. Thus, the present study aimed to assess the therapeutic effect of BER in human ATC cell lines CAL-62 and BHT-101 as well as the underlying mechanisms. In addition, we assessed the antitumor effects of a combination of BER and DOX in ATC cells. Methods: The cell viability of CAL-62 and BTH-101 with treatment of BER for different hours was measured by CCK-8 assay, and cell apoptosis was assessed by clone formation assay and flow cytometric analysis. The protein levels of apoptosis protein, autophagy-related proteins and PI3K/AKT/mTORpathway were determined Using Western blot. Autophagy in cells was observed with GFP-LC3 plasmid using confocal fluorescent microscopy. Flow cytometry was used to detect intracellular ROS. Results: The present results showed that BER significantly inhibited cell growth and induced apoptosis in ATC cells. BER treatment also significantly upregulated the expression of LC3B-II and increased the number of GFP-LC3 puncta in ATC cells. Inhibition of autophagy by 3-methyladenine (3-MA) suppressed BER-induced autophagic cell death. Moreover, BER induced the generation of reactive oxygen species (ROS). Mechanistically, we demonstrated that BER regulated the autophagy and apoptosis of human ATC cells through the PI3K/AKT/mTOR pathways. Furthermore, BER and DOX cooperated to promote apoptosis and autophagy in ATC cells. Conclusion: Taken together, the present findings indicated that BER induces apoptosis and autophagic cell death by activating ROS and regulating the PI3K/AKT/mTOR signaling pathway.

Bradykinin protects against DDP-induced GP-H1 cell damage via activation of PI3K/Akt/NO signaling pathway.

OBJECTIVE: To investigate the effect of bradykinin (BK) on cisplatin (DDP)-induced cardiotoxicity at the cellular level and its cytological mechanism. METHODS: The toxic effects of DDP on GP-H1 cells, and the effects of BK on DDP cardiomyocyte survival rate, DDP-induced malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD), reactive oxygen species (ROS), mitochondria membrane potential (MMP) and apoptosis were explored. RESULTS: DDP at different concentrations inhibited GP-H1 cells at 12 h after administration, and the inhibitory effect was more prominent at 24 h after administration and continued until 72 h after administration. The severity of GP-H1 cell damage induced by DDP was reduced by 0.1 µM, 1 µM, and 10 µM BK. After GP-H1 cells were treated with DDP, ROS levels increased and MMP levels decreased, while BK intervention inhibited these effects. At 24 h after DDP treatment, Bax/bcl-2 increased in GP-H1 cells, and the expressions of Caspase-3, p-NF-κB, p-p38 and p-Smad2 decreased. After intervention with BK, it was shown that Bax/Bcl-2 was significantly reduced, and the expressions of Caspase-3, p-NF-κB, p-p38 and p-Smad2 decreased. Bax/Bcl-2 and the expressions of Caspase-3, p-NF-κB, p-p38 and p-Smad2 of GP-H1 cells were basically not affected by BK alone. CONCLUSION: The protective effect of BK on DDP-induced GP-H1 cell damage in guinea pig is related to the activation of PI3K/Akt/NO signaling pathway by BK, which reduces oxidative stress levels in cardiomyocytes and also acts as an anti-apoptotic agent.

Integrated metabolomics and network analysis reveal changes in lipid metabolisms of tripterygium glycosides tablets in rats with collagen-induced arthritis.

Tripterygium glycosides tablets (TGT) are the commonly used preparation for rheumatoid arthritis (RA). However, the changes in TGT on RA are still unclear at the metabolic level. This study aimed to reveal the biological processes of TGT in collagen-induced arthritis (CIA) rats through integrated metabolomics and network analysis. First, the CIA model in rats was established, and the CIA rats were given three doses of TGT. Then, the endogenous metabolites in the serum from normal rats, CIA rats, and CIA rats treated with varying doses of TGT were detected by UHPLC-QTOF-MS/MS. Next, univariate and multivariate statistical analyses were performed to find the differential metabolites. Finally, differential metabolites, metabolic pathways, and hub genes were analyzed integrally to reveal the biological processes of TGT in CIA rats. The paw diameter, arthritis score, immunoglobulin G (IgG) concentration, CT image, and histological assay showed that TGT had evident therapeutic effects on CIA rats. Untargeted metabolomics revealed that TGT could ameliorate the down-regulation of lipid levels in CIA rats. Four key differential metabolites were found including LysoP(18:0), LysoPA(20:4), LysoPA(18:2), and PS(O-20:0/17:1). The glycerophospholipid metabolic pathway was perturbed in treating CIA with TGT. A total of 24 genes, including PLD1, LPCAT4, AGPAT1, and PLA2G4A, were found to be the hub genes of TGT in CIA rats. In conclusion, the integrated analysis provided a novel and holistic perspective on the biological processes of TGT in CIA rats, which could give helpful guidance for further TGT on RA. Future studies based on human samples are necessary.

Therapeutic effects of atorvastatin on doxorubicin-induced hepatotoxicity in rats via antioxidative damage, anti-inflammatory, and anti-lipotoxicity.

Doxorubicin (DOX), is a high efficiency anthracycline antitumor drug. However, the clinical application of DOX is limited mainly by dose-related adverse drug reactions. Currently, the therapeutic effects of Atorvastatin (ATO) on DOX-induced hepatotoxicity were studied in vivo. The results indicated that DOX impaired hepatic function, as measured by an increased levels of liver weight index and serum concentrations of aspartate transaminase and alanine transaminase, as well as alteration of hepatic histology. In addition, DOX increased the serum levles of triglyceride (TG) and nonestesterified fatty acid. ATO prevented these changes. Mechanical analysis revealed that ATO restored the changes of malondialdehyde, reactive oxygen radical species, glutathione peroxidase and manganese superoxide dismutase. Additionally, ATO inhibited the increased expression levels of nuclear factor-kappa B and interleukin 1ß, hence suppressing inflammation. Meanwhile, ATO inhibited cell apoptosis by dramatically decreasing the Bax/Bcl-2 ratio. In addition, ATO mitigated the lipidtoxicity by inhibiting the adipolysis of TG and accelerating hepatic lipid metabolism. Taken together, the results suggest ATO has therapeutic effect on DOX-induced hepatotoxicity via inhibition of oxidative damage, inflammatory and apoptosis. In addition, ATO attenuates DOX-induced hyperlipidemia via modulation of lipid metabolism.

Revealment study on the regulation of lipid metabolism by Lingguizhugan Decoction in heart failure treatment based on integrated lipidomics and proteomics.

Lingguizhugan Decoction (LGZGD) is a classical traditional Chinese medicine prescription. Our previous studies found that disorders of lipid metabolism were reversed by LGZGD in heart failure (HF) mice. This study aimed to reveal the regulation of lipid metabolism of LGZGD. A mice model of HF was established by intraperitoneal injection of doxorubicin. The components of LGZGD were identified with the UHPLC-QTOF-MS method. The regulation of lipid metabolism by LGZGD was detected by serum lipidomics and heart tissue proteomics. Molecular docking was further performed to screen active components. A total of 78 compounds in LGZGD were identified. Results of lipidomics showed that 37 lipids illustrated a significant recovery trend to normal after the treatment of LGZGD. Results of proteomics demonstrated that 55 proteins were altered by the administration of LGZGD in HF mice. After enrichment analysis, the Prakg2/Ucp2/Plin1 axis on the Apelin pathway plays a vital role in HF treatment by LGZGD. Nine active components exhibited the outstanding ability of binding to the apelin receptor with MM-GBSA value lower than -60 Kcal/mol. In conclusion, all results combined together revealed that multi-component in the LGZGD had beneficial effects on the HF through ameliorating lipid disorders, which provides a novel insight into the cardioprotective effects of LGZGD and its clinical application.

Synchronous Investigation of the Mechanism and Substance Basis of Tripterygium Glycosides Tablets on Anti-rheumatoid Arthritis and Hepatotoxicity.

Tripterygium Glycosides Tablets (TGT) has shown obvious anti-rheumatoid arthritis (RA) effects accompanied by hepatotoxicity. Despite that many studies looked at TGT's anti-RA or hepatotoxic mechanism and substance basis, the results were still insufficient. Furthermore, the anti-RA and hepatotoxicity investigations of TGT were undertaken separately, neglecting the relationship between efficacy and toxicity. Herein, an integrated approach combining metabolomics, network pharmacology, serum pharmacochemistry, and molecular docking was adopted to elucidate the mechanism and substance basis of Tripterygium Glycosides Tablets (TGT) on anti-rheumatoid arthritis and hepatotoxicity simultaneously. The results showed that 33 components in TGT were absorbed into rat serum. Two toxic targets (PRKCA, FASN), three effective targets (PLA2G10, PTGES, PLA2G1B), and four effective and toxic targets (PTGS1, PTGS2, PLA2G2A, ALOX5) were obtained by metabolomics combined with network analysis and network pharmacology. A component-target-RA-hepatotoxicity network was constructed and five hepatotoxic components (1-desacetylwilforgine, wilfordconine, wilforgine, wilformine, wilfornine D), eight effective-toxic components (14-oxo-19-(4 → 3) abeo-abieta-3,8,12-tetraen-19,18-olide, 7-oxo-18(4 → 3) abeo-abieta-3,8,11,13-tetraen-18-oic acid, hypoglaulide, triptotriterpenic acid A, wilforol F, wilforlide B, triptoquinone B, wilforlide A); and 23 non-effective and non-toxic components were acquired and validated by molecular docking. In addition, our research revealed that glycerophospholipid metabolism and ether lipid metabolism were correlated to both hepatotoxicity and anti-RA of TGT. While in sphingolipid metabolism, ceramidases regulated ceramide-sphingosine and phytoceramide-phytosphingosine reaction were found to be correlated to hepatotoxicity, sphinganine-1-phosphate lyase (SPL) regulated sphingosine 1-phosphate (S1P)-phosphoethanolamine and sphinganine 1-phosphate-phosphoethanolamine were found to be attributed to anti-RA effects.

ROCK inhibitor fasudil reduces the expression of inflammatory factors in LPS-induced rat pulmonary microvascular endothelial cells via ROS/NF-κB pathway.

BACKGROUND: Inflammation plays a major role in the pulmonary artery hypertension (PAH) and the acute lung injury (ALI) diseases. The common feature of these complications is the dysfunction of pulmonary microvascular endothelial cells (PMVECs). Fasudil, the only Rho kinase (ROCK) inhibitor used in clinic, has been proved to be the most promising new drug for the treatment of PAH, with some anti-inflammatory activity. Therefore, in the present study, the effect of fasudil on lipopolysaccharide (LPS)-induced inflammatory injury in rat PMVECs was investigated. METHODS: LPS was used to make inflammatory injury model of rat PMVECs. Thereafter, the mRNA and protein expression of pro-inflammatory factors was evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) assay respectively. Intracellular reactive oxygen species (ROS) levels were measured by the confocal laser scanning system. The activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the content of malondialdehyde (MDA) were determined by using commercial kits according to the manufacturer's instructions. Western blot assay was used to detect the protein expression of nuclear factor kappa B (NF-κB) p65. RESULTS: Fasudil effectively prevented inflammatory injury induced by LPS, which is manifested by the decrease of pro-inflammatory cytokines interleukin-6 (IL-6) and monocyte chenotactic protein-1 (MCP-1). Meanwhile, fasudil dramatically reduced the levels of ROS and MDA, and also elevated the activities of SOD and GSH-Px. Furthermore, the nuclear translocation of NF-κB p65 induced by LPS was also suppressed by fasudil. Additionally, the ROS scavengers N-Acetylcysteine (N-Ace) was also found to inhibit the nuclear translocation of NF-κB and the mRNA expression of IL-6 and MCP-1 induced by LPS, which suggested that ROS was essential for the nuclear translocation of NF-κB. CONCLUSIONS: The present study revealed that fasudil reduced the expression of inflammatory factors, alleviated the inflammatory and oxidative damage induced by LPS in rat PMVECs via ROS-NF-κB signaling pathway.

Inhibition of the INa/K and the activation of peak INa contribute to the arrhythmogenic effects of aconitine and mesaconitine in guinea pigs.

Aconitine (ACO), a main active ingredient of Aconitum, is well-known for its cardiotoxicity. However, the mechanisms of toxic action of ACO remain unclear. In the current study, we investigated the cardiac effects of ACO and mesaconitine (MACO), a structurally related analog of ACO identified in Aconitum with undocumented cardiotoxicity in guinea pigs. We showed that intravenous administration of ACO or MACO (25 µg/kg) to guinea pigs caused various types of arrhythmias in electrocardiogram (ECG) recording, including ventricular premature beats (VPB), atrioventricular blockade (AVB), ventricular tachycardia (VT), and ventricular fibrillation (VF). MACO displayed more potent arrhythmogenic effect than ACO. We conducted whole-cell patch-clamp recording in isolated guinea pig ventricular myocytes, and observed that treatment with ACO (0.3, 3 µM) or MACO (0.1, 0.3 µM) depolarized the resting membrane potential (RMP) and reduced the action potential amplitude (APA) and durations (APDs) in a concentration-dependent manner. The ACO- and MACO-induced AP remodeling was largely abolished by an INa blocker tetrodotoxin (2 µM) and partly abolished by a specific Na+/K+ pump (NKP) blocker ouabain (0.1 µM). Furthermore, we observed that treatment with ACO or MACO attenuated NKP current (INa/K) and increased peak INa by accelerating the sodium channel activation with the EC50 of 8.36 ± 1.89 and 1.33 ± 0.16 µM, respectively. Incubation of ventricular myocytes with ACO or MACO concentration-dependently increased intracellular Na+ and Ca2+ concentrations. In conclusion, the current study demonstrates strong arrhythmogenic effects of ACO and MACO resulted from increasing the peak INa via accelerating sodium channel activation and inhibiting the INa/K. These results may help to improve our understanding of cardiotoxic mechanisms of ACO and MACO, and identify potential novel therapeutic targets for Aconitum poisoning.

Comprehensive analysis of transcriptomics and metabolomics to understand triptolide-induced liver injury in mice.

Triptolide, a major active component of Triptergium wilfordii Hook. f, is used in the treatment of autoimmune disease. However, triptolide is associated with severe adverse reactions, especially hepatotoxicity, which limits its clinical application. To examine the underlying mechanism of triptolide-induced liver injury, a combination of dose- and time-dependent toxic effects, RNA-seq and metabolomics were employed. Triptolide-induced toxicity occurred in a dose- and time-dependent manners and was characterized by apoptosis and not necroptosis. Transcriptomics profiles of the dose-dependent response to triptolide suggested that PI3K/AKT, MAPK, TNFα and p53 signaling pathways were the vital steps in triptolide-induced hepatocyte apoptosis. Metabolomics further revealed that glycerophospholipid, fatty acid, leukotriene, purine and pyrimidine metabolism were the major metabolic alterations after triptolide exposure. Finally, acylcarnitines were identified as potential biomarkers for the early detection of triptolide-induced liver injury.

The lncRNA TDRG1 promotes cell proliferation, migration and invasion by targeting miR-326 to regulate MAPK1 expression in cervical cancer.

BACKGROUND: Recently, lncRNA-Testis developmental related gene 1 (TDRG1) was proved to be a key modulator in reproductive organ-related cancers. The biological role of TDRG1 in cervical cancer (CC) progression remains largely unknown. METHOD: Real-time PCR (qRT-PCR) examined the expression level of TDRG1, microRNA (miR)-326 and MAPK1 mRNA. OS tissues and corresponding relative normal tissues, as well as CC cell lines and normal cell line Ect1/E6E7 were collected to determine the expression of TDRG1 in CC. MTT, colony formation, wound-healing, transwell and flow cytometer assay detected the influence of TDRG1 and miR-326 on CC cells growth, metastasis and apoptosis. Western blot examined proteins level. Bioinformatics, RNA pull-down assay, RNA immunoprecipitation and dual-luciferase reporter assays detected the molecular mechanism of TDRG1 in CC. Xenograft tumour model was established to determine the role of TDRG1 in vivo. RESULTS: The expression of TDRG1 was significantly increased in CC tissues and cell lines compared with normal tissue and normal cell line respectively and its expression was associated with clinicopathological characteristics of CC patients. Knockdown of TDRG1 inhibited the cell proliferation, migration and invasion in Hela and SIHA cells. Moreover, TDRG1 directly interacted with miR-326, and the inhibition effect on cell growth and metastasis induced by TDRG1 siRNA can be abrogated by miR-326 silencing by its inhibitor in Hela and SIHA cells. Further, MAPK1 was proved to be a direct target of miR-326, and its expression was negatively regulated by miR-326 while positively modulated by TDRG1. CONCLUSION: TDRG1 acts as a competing endogenous lncRNA (ceRNA) to modulate MAPK1 by sponging miR-326 in CC, shedding new light on TDRG1-directed diagnostics and therapeutics in CC.

Protective effect of berberine on aconite­induced myocardial injury and the associated mechanisms.

Aconitum plants, which have analgesic, diuretic and anti­inflammatory effects, have been widely used to treat various types of disease. However, the apparent toxicity of Aconitum­derived agents, particularly in the cardiovascular system, has largely limited their clinical use. Thus, the present study investigated whether berberine (Ber), an isoquinoline alkaloid, may reduce myocardial injury induced by aconitine (AC) in rats and the underlying mechanisms. Rats (n=40) were randomly divided into four groups: Control, Chuan­wu and Chuan­wu + Ber (8 and 16 mg/kg doses). Electrocardiograms (ECG) of the rats were recorded and serum biomarkers of cardiac function [lactate dehydrogenase (LDH), creatine kinase (CK) and CK­MB] were assayed. Histopathological changes were assessed using myocardial tissue sectioning and hematoxylin and eosin staining. Additionally, the effects of Ber on AC­induced arrhythmias in rats were observed. The changes in ECG following AC perfusion were observed, and the types and onset time of arrhythmias were analyzed. Furthermore, the effects of Ber and AC on papillary muscle action potentials were observed. The results suggested that Ber ameliorated myocardial injury induced by Chuan­wu, which was indicated by reduced arrhythmias and decreased LDH, CK and CK­MB levels in serum. Furthermore, histological damage, including dilation of small veins and congestion, was also markedly attenuated by Ber. In addition, the occurrence of arrhythmias was significantly delayed, and the dosage of AC required to induce arrhythmias was also increased by Ber pretreatment. Additionally, AC­induced changes in action potential amplitude, duration of 30% repolarization and duration of 90% repolarization in the papillary muscle were attenuated by Ber. All of these results indicate that Ber had a preventive effect on acute myocardial injury induced by Chuan­wu and arrhythmias caused by AC, which may be associated with the inhibition of delayed depolarization and triggered activity caused by AC. Thus, combination treatment of Ber with Aconitum plants may be a novel strategy to prevent AC­induced myocardial injury in clinical practice.

Protective effect of berberine on acute cardiomyopathy associated with doxorubicin treatment.

Doxorubicin (DOX) is a potent and broad-spectrum anthracycline chemotherapeutic agent, but dose-dependent cardiotoxic side effects limit its clinical application. This toxicity is closely associated with the generation of reactive oxygen species (ROS) radical during DOX metabolism. The present study investigated the effects of Berberine (Ber) on DOX-induced acute cardiac injury in a rat model and analysed its mechanism in cardiomyocytes in vitro. Serum creatine kinase (CK), creatine kinase isoenzyme (CK-MB) and malondialdehyde (MDA) levels were significantly increased in the DOX group compared with the control group. This increase was accompanied by cardiac histopathological injury and a decrease in cardiomyocyte superoxide dismutase (SOD) and catalase (CAT). CK, CK-MB and MDA levels decreased and SOD and CAT levels increased in the Ber-treated group compared to the DOX group. Ber ameliorated the DOX-induced increase in cytosolic calcium concentration ([Ca2+]i), attenuated mitochondrial Ca2+ overload and restored the DOX-induced loss of mitochondrial membrane potential in vitro. These results demonstrated that Ber exhibited protective effects against DOX-induced heart tissue free radical injury, potentially via the inhibition of intracellular Ca2+ elevation and attenuation of mitochondrial dysfunction.

L-Type Calcium Channel Inhibition Contributes to the Proarrhythmic Effects of Aconitine in Human Cardiomyocytes.

Aconitine (ACO) is well-known for causing lethal ventricular tachyarrhythmias. While cardiac Na+ channel opening during repolarization has long been documented in animal cardiac myocytes, the cellular effects and mechanism of ACO in human remain unexplored. This study aimed to assess the proarrhythmic effects of ACO in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). ACO concentration-dependently (0.3 ~ 3.0 µM) shortened the action potentials (AP) durations (APD) in ventricular-like hiPSC-CMs by > 40% and induced delayed after-depolarization. Laser-scanning confocal calcium imaging analysis showed that ACO decreased the duration and amplitude of [Ca2+]i transients and increased in the beating frequencies by over 60%. Moreover, ACO was found to markedly reduce the L-type calcium channel (LTCC) currents (ICa,L) in hiPSC-CMs associated with a positive-shift of activation and a negative shift of inactivation. ACO failed to alter the peak and late Na+ currents (INa) in hiPSC-CMs while it drastically increased the late INa in Guinea-pig ventricular myocytes associated with enhanced activation/delayed inactivation of INa at -55 mV~ -85 mV. Further, the effects of ACO on ICa,L, INa and the rapid delayed rectifier potassium current (Ikr) were validated in heterologous expression systems by automated voltage-clamping assays and a moderate suppression of Ikr was observed in addition to concentration-dependent ICa,L inhibition. Lastly, increased beating frequency, decreased Ca2+ wave and shortened field potential duration were recorded from hiPSC-CMs by microelectrode arrays assay. In summary, our data demonstrated that LTCC inhibition could play a main role in the proarrhythmic action of ACO in human cardiomyocytes.

Efficacy and Safety of Pulmonary Arterial Hypertension-specific Therapy in Pulmonary Arterial Hypertension: A Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Previous meta-analyses of pulmonary arterial hypertension (PAH)-specific therapy for PAH pooled PAH-specific combination therapy and monotherapy. This flaw may threaten the authenticity of their findings. METHODS: PubMed, Embase, and the Cochrane Library were searched for randomized controlled trials that evaluated any PAH-specific medications in the treatment of PAH. We calculated ORs with 95% CIs for dichotomous data and standardized mean differences for continuous data. RESULTS: In total, 35 randomized controlled trials involving 6,702 patients were included. In monotherapy vs placebo/conventional therapy, significance was obtained in mortality reduction (OR, 0.50 [95% CI, 0.33 to 0.76]; P = .001), 6-min walk test (mean difference, 31.10 m [95% CI, 25.40 to 36.80]; P < .00001), New York Heart Association/World Health Organization functional class (OR, 2.48 [95% CI, 1.51 to 4.07]; P = .0003), and hemodynamic status based on mean pulmonary artery pressure, pulmonary vascular resistance, cardiac index, and incidence of withdrawal due to adverse effects. In combination therapy vs monotherapy, significance was reached for the 6-min walk test (mean difference, 19.96 m [95% CI, 15.35 to 24.57]; P < .00001), functional class (OR, 1.65 [95% CI, 1.20 to 2.28]; P = .002), hemodynamic status, and incidence of withdrawal due to adverse effects (OR, 2.01 [95% CI, 1.54 to 2.61]; P < .00001) but not for mortality reduction (OR, 0.98 [95% CI, 0.57 to 1.68]; P = .94). CONCLUSIONS: Our meta-analysis revealed that PAH-specific monotherapy could improve mortality, exercise capacity, functional class, and hemodynamic status compared with placebo or conventional therapy. However, combination therapy could further improve exercise capacity, functional class, and hemodynamic status compared with monotherapy, but it had no proven effect on mortality. Combination therapy had a much higher incidence of withdrawal due to adverse effects than monotherapy.

Protective effect of berberine on doxorubicin­induced acute hepatorenal toxicity in rats.

Doxorubicin (DOX), a potent broad­spectrum chemotherapeutic agent used for the treatment of several types of cancer, is largely limited due to its serious side effects on non­target organs. Thus, the present study aimed to investigate whether berberine (Ber), an isoquinoline alkaloid, could reduce DOX­induced acute hepatorenal toxicity in rats. Fifty rats were randomly divided into five groups: i) Control group, ii) DOX group, iii) DOX+Ber (5 mg kg) group; iv) DOX+Ber (10 mg kg), and v) DOX+Ber (20 mg kg) group. In the tests, body weight, organ index, general condition and mortality were observed. In addition, the serum levels of alanine transaminase (ALT), aspartate aminotransferase (AST), total cholesterol (TCHO) and blood urea nitrogen (BUN) were determined to evaluate hepatorenal function. Hepatorenal toxicity was further assessed using hematoxylin and eosin stained sections. Furthermore, the levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and malondialdehyde (MDA) in rat serum or tissue homogenate were also assessed to determine the mechanisms of action. Results suggested that pretreatment with Ber ameliorated the DOX­induced liver and kidney injury by lowering the serum ALT, AST, TCHO and BUN levels, and the damage observed histologically, such as hemorrhage and focal necrosis of liver and kidney tissues induced by DOX were also attenuated by Ber. Furthermore, Ber also exerted certain antioxidative properties through reversing the changes in the levels of MDA, SOD, GSH and MDA induced by DOX. These findings indicate that Ber has protective effects against DOX­induced acute hepatorenal toxicity in rats. Combination of Ber with DOX is a novel strategy that has the potential for protecting against DOX­induced hepatorenal toxicity in clinical practice.

Exogenous melatonin for sleep disorders in neurodegenerative diseases: a meta-analysis of randomized clinical trials.

The purpose of this work is to investigate the efficacy of exogenous melatonin in the treatment of sleep disorders in patients with neurodegenerative disease. We searched Pubmed, the Cochrane Library, and ClinicalTrials.gov, from inception to July 2015. We included randomized clinical trials (RCTs) that compared melatonin with placebo and that had the primary aim of improving sleep in people with neurodegenerative diseases, particularly Alzheimer's disease (AD) and Parkinson's disease (PD). We pooled data with the weighted mean difference in sleep outcomes. To assess heterogeneity in results of individual studies, we used Cochran's Q statistic and the I (2) statistic. 9 RCTs were included in this research. We found that the treatment with exogenous melatonin has positive effects on sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI) in PD patients (MD: 4.20, 95 % CI: 0.92-7.48; P = 0.01), and by changes in PSQI component 4 in AD patients (MD: 0.67, 95 % CI: 0.04-1.30; P = 0.04), but not on objective sleep outcomes in both AD and PD patients. Treatment with melatonin effectively improved the clinical and neurophysiological aspects of rapid eye movement (REM) sleep behavior disorder (RBD), especially elderly individuals with underlying neurodegenerative disorders. This meta-analysis provided some evidence that melatonin improves sleep quality in patients with AD and PD, and melatonin can be considered as a possible sole or add-on therapy in neurodegenerative disorders patients with RBD.