Low-Dose Colchicine Ameliorates Doxorubicin Cardiotoxicity Via Promoting Autolysosome Degradation.

BACKGROUND: The only clinically approved drug that reduces doxorubicin cardiotoxicity is dexrazoxane, but its application is limited due to the risk of secondary malignancies. So, exploring alternative effective molecules to attenuate its cardiotoxicity is crucial. Colchicine is a safe and well-tolerated drug that helps reduce the production of reactive oxygen species. High doses of colchicine have been reported to block the fusion of autophagosomes and lysosomes in cancer cells. However, the impact of colchicine on the autophagy activity within cardiomyocytes remains inadequately elucidated. Recent studies have highlighted the beneficial effects of colchicine on patients with pericarditis, postprocedural atrial fibrillation, and coronary artery disease. It remains ambiguous how colchicine regulates autophagic flux in doxorubicin-induced heart failure. METHODS AND RESULTS: Doxorubicin was administered to establish models of heart failure both in vivo and in vitro. Prior studies have reported that doxorubicin impeded the breakdown of autophagic vacuoles, resulting in damaged mitochondria and the accumulation of reactive oxygen species. Following the administration of a low dose of colchicine (0.1 mg/kg, daily), significant improvements were observed in heart function (left ventricular ejection fraction: doxorubicin group versus treatment group=43.75%±3.614% versus 57.07%±2.968%, P=0.0373). In terms of mechanism, a low dose of colchicine facilitated the degradation of autolysosomes, thereby mitigating doxorubicin-induced cardiotoxicity. CONCLUSIONS: Our research has shown that a low dose of colchicine is pivotal in restoring the autophagy activity, thereby attenuating the cardiotoxicity induced by doxorubicin. Consequently, colchicine emerges as a promising therapeutic candidate to improve doxorubicin cardiotoxicity.

Ginsenoside Rb1 attenuates doxorubicin induced cardiotoxicity by suppressing autophagy and ferroptosis.

Ginsenoside Rb1 (Rb1), an active component isolated from traditional Chinese medicine Ginseng, is beneficial to many cardiovascular diseases. However, whether it can protect against doxorubicin induced cardiotoxicity (DIC) is not clear yet. In this study, we aimed to investigate the role of Rb1 in DIC. Mice were injected with a single dose of doxorubicin (20 mg/kg) to induce acute cardiotoxicity. Rb1 was given daily gavage to mice for 7 days. Changes in cardiac function, myocardium histopathology, oxidative stress, cardiomyocyte mitochondrion morphology were studied to evaluate Rb1's function on DIC. Meanwhile, RNA-seq analysis was performed to explore the potential underline molecular mechanism involved in Rb1's function on DIC. We found that Rb1 treatment can improve survival rate and body weight in Dox treated mice group. Rb1 can attenuate Dox induced cardiac dysfunction and myocardium hypertrophy and interstitial fibrosis. The oxidative stress increase and cardiomyocyte mitochondrion injury were improved by Rb1 treatment. Mechanism study found that Rb1's beneficial role in DIC is through suppressing of autophagy and ferroptosis. This study shown that Ginsenoside Rb1 can protect against DIC by regulating autophagy and ferroptosis.

PLEKHM2 deficiency induces impaired mitochondrial clearance and elevated ROS levels in human iPSC-derived cardiomyocytes.

Pleckstrin homology domain-containing family M member 2 (PLEKHM2) is an essential adaptor for lysosomal trafficking and its homozygous truncation have been reported to cause early onset dilated cardiomyopathy (DCM). However, the molecular mechanism of PLEKHM2 deficiency in DCM pathogenesis and progression is poorly understood. Here, we generated an in vitro model of PLEKHM2 knockout (KO) induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) to elucidate the potential pathogenic mechanism of PLEKHM2-deficient cardiomyopathy. PLEKHM2-KO hiPSC-CMs developed disease phenotypes with reduced contractility and impaired calcium handling. Subsequent RNA sequencing (RNA-seq) analysis revealed altered expression of genes involved in mitochondrial function, autophagy and apoptosis in PLEKHM2-KO hiPSC-CMs. Further molecular experiments confirmed PLEKHM2 deficiency impaired autophagy and resulted in accumulation of damaged mitochondria, which triggered increased reactive oxygen species (ROS) levels and decreased mitochondrial membrane potential (Δψm). Importantly, the elevated ROS levels caused oxidative stress-induced damage to nearby healthy mitochondria, resulting in extensive Δψm destabilization, and ultimately leading to impaired mitochondrial function and myocardial contractility. Moreover, ROS inhibition attenuated oxidative stress-induced mitochondrial damage, thereby partially rescued PLEKHM2 deficiency-induced disease phenotypes. Remarkably, PLEKHM2-WT overexpression restored autophagic flux and rescued mitochondrial function and myocardial contractility in PLEKHM2-KO hiPSC-CMs. Taken together, these results suggested that impaired mitochondrial clearance and increased ROS levels play important roles in PLEKHM2-deficient cardiomyopathy, and PLEKHM2-WT overexpression can improve mitochondrial function and rescue PLEKHM2-deficient cardiomyopathy.

Enhanced myofilament calcium sensitivity aggravates abnormal calcium handling and diastolic dysfunction in patient-specific induced pluripotent stem cell-derived cardiomyocytes with MYH7 mutation.

Hypertrophic cardiomyopathy (HCM), the most common inherited heart disease, is frequently caused by mutations in the ß-cardiac myosin heavy chain gene (MYH7). Abnormal calcium handling and diastolic dysfunction are archetypical features of HCM caused by MYH7 gene mutations. However, the mechanism of how MYH7 mutations leads to these features remains unclear, which inhibits the development of effective therapies. Initially, cardiomyocytes were generated from induced pluripotent stem cells from an eight-year-old girl diagnosed with HCM carrying a MYH7(C.1063 G>A) heterozygous mutation(mutant-iPSC-CMs) and mutation-corrected isogenic iPSCs(control-iPSC-CMs) in the present study. Next, we compared phenotype of mutant-iPSC-CMs to that of control-iPSC-CMs, by assessing their morphology, hypertrophy-related genes expression, calcium handling, diastolic function and myofilament calcium sensitivity at days 15 and 40 respectively. Finally, to better understand increased myofilament Ca2+ sensitivity as a central mechanism of central pathogenicity in HCM, inhibition of calcium sensitivity with mavacamten can improveed cardiomyocyte hypertrophy. Mutant-iPSC-CMs exhibited enlarged areas, increased sarcomere disarray, enhanced expression of hypertrophy-related genes proteins, abnormal calcium handling, diastolic dysfunction and increased myofilament calcium sensitivity at day 40, but only significant increase in calcium sensitivity and mild diastolic dysfunction at day 15. Increased calcium sensitivity by levosimendan aggravates cardiomyocyte hypertrophy phenotypes such as expression of hypertrophy-related genes, abnormal calcium handling and diastolic dysfunction, while inhibition of calcium sensitivity significantly improves cardiomyocyte hypertrophy phenotypes in mutant-iPSC-CMs, suggesting increased myofilament calcium sensitivity is the primary mechanisms for MYH7 mutations pathogenesis. Our studies have uncovered a pathogenic mechanism of HCM caused by MYH7 gene mutations through which enhanced myofilament calcium sensitivity aggravates abnormal calcium handling and diastolic dysfunction. Correction of the myofilament calcium sensitivity was found to be an effective method for treating the development of HCM phenotype in vitro.

Saccharides from Arctium lappa L. root reduce platelet activation and thrombus formation in a laser injury thrombosis mouse model.

Arctium lappa L., also known as burdock, is a popular medicinal plant in traditional Chinese medicine due to its potential therapeutic properties. Saccharides from Arctium lappa L. root (ALR-S) have been extensively studied for their anti-inflammatory and anti-diabetes effects. Platelets play a pivotal role in thrombosis. The present study describes the effects of ALR-S on platelet activation and thrombosis using a laser injury thrombosis in vivo model. The study also measured the effects of ALR-S on platelet activation by analysing aggregation, ATP release, platelet spreading, adhesion and clot retraction in vitro. Specifically, the effects were ALR-S concentration-dependent inhibition of platelet aggregation and ATP release. Activated platelets pretreated with ALR-S showed diminished CD62P expression levels and fibrinogen binding, as measured by flow cytometry. ALR-S inhibited platelet spreading on fibrinogen and adhesion on collagen under shear. ALR-S attenuated platelet activation by decreasing oxidative stress and thrombus formation. These results demonstrated the antiplatelet effects of ALR-S, suggesting the antithrombotic and cardiovascular protective activities of ALR-S as a functional food.

A heterozygous MYBPC3 (c. 772+1G > A) mutant human induced pluripotent stem cell line (ZZUNEUi025-A) generated from a male patient with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is the most common heterogeneous myocardial disease. MYBPC3 variants are the leading cause of HCM. In the present study, a human induced pluripotent stem cell (iPSC) line ZZUNEUi025-A was generated from peripheral blood mononuclear cells of a male HCM patient with c. 772+1G > A in MYBPC3 gene. This cell line expressed pluripotency markers, had normal male karyotype and could differentiate into three germ layers in vitro.

Generation of a human iPSC line ZZUNEUi014-A from a patient with antithrombin deficiency caused by mutation in SERPINC1 gene.

Inherited antithrombin (AT) deficiency is an autosomal dominant disorder associated with SERPINC1 mutations. In this study, we generated a human induced pluripotent stem cell (iPSC) line ZZUNEUi014-A from peripheral blood mononuclear cells of a female AT deficiency patient with the p. W27X (c. 80G > A) mutation in SERPINC1. This cell line expressed pluripotency markers, showed normal female karyotype and could differentiate into all three germ layers in vitro.

Deletion of Seipin Attenuates Vascular Function and the Anticontractile Effect of Perivascular Adipose Tissue.

Seipin locates in endoplasmic reticulum (ER) and regulates adipogenesis and lipid droplet formation. Deletion of Seipin has been well-demonstrated to cause severe general lipodystrophy, however, its role in maintaining perivascular adipose tissue (PVAT) and vascular homeostasis has not been directly assessed. In the present study, we investigated the role of Seipin in mediating the anticontractile effect of PVAT and vascular function. Seipin expression in PVAT and associated vessels were detected by qPCR and western-blot. Seipin is highly expressed in PVAT, but hardly in vessels. Structural and functional alterations of PVAT and associated vessels were compared between Seipin -/- mice and WT mice. In Seipin -/- mice, aortic and mesenteric PVAT were significantly reduced in mass and adipose-derived relaxing factors (ADRFs) secretion, but increased in macrophage infiltration and ER stress, as compared with those in WT mice. Aortic and mesenteric artery rings from WT and Seipin -/- mice were mounted on a wire myograph. Vasoconstriction and vasodilation were studied in vessels with and without PVAT. WT PVAT augmented relaxation but not Seipin -/- PVAT, which suggest impaired anticontractile function in PVAT of Seipin -/- mice. Thoracic aorta and mesenteric artery from Seipin -/- mice had impaired contractility in response to phenylephrine (PHE) and relaxation to acetylcholine (Ach). In conclusion, Seipin deficiency caused abnormalities in PVAT morphology and vascular functions. Our data demonstrated for the first time that Seipin plays a critical role in maintaining PVAT function and vascular homeostasis.

BCAT1 knockdown-mediated suppression of melanoma cell proliferation and migration is associated with reduced oxidative phosphorylation.

Malignant melanoma has a high mutational rate. As a result, resistance to current therapies is common. Consequently, there is an unmet medical need to develop novel therapies. Recent data suggest that branched-chain amino acid transaminase 1 (BCAT1) is overexpressed in multiple cancers, and such overexpressed BCAT1 is necessary for individual cancer progression. Therefore, BCAT1 appears to be a good target in cancer treatment. Additionally, because its expression in healthy tissues is highly restricted in adults and is limited to the brain, ovary, and placenta, BCAT1 is especially an ideal target in cancer therapies. Currently, the function of BCAT1 in malignant melanoma has not been demonstrated. Therefore, we investigated the role of BCAT1 in the proliferation and migration of malignant melanomas using human samples and mouse malignant B16 melanoma cell line. Our data showed that BCAT1 was overexpressed in malignant melanoma tissues both in humans and mice. Besides, BCAT1 knockdown suppressed melanoma cell proliferation and migration, which was associated with reduced oxidative phosphorylation. Collectively, our data indicate that BCAT1 is a promising therapeutic target for the treatment of malignant melanomas.

Induced pluripotent stem cell (iPSC) line (ZZUNEUi009-A) from a healthy female individual.

Induced pluripotent stem cells (iPSCs) can be used to generate different types of somatic cells in vitro and are a useful tool for investigating drug and disease mechanisms. Here, we generated human induced pluripotent stem cell (iPSC) line ZZUNEUi009-A from an apparently healthy 28-year-old female by reprogramming peripheral blood mononuclear cells with non-integrating vector. The generated iPSCs was pluripotent, maintained a stable karyotype, and could generate the three layers (ectoderm, mesoderm, and endoderm) in vitro.

An induced pluripotent stem cells line (ZZUNEUi022-A) derived from urine cells of healthy male human.

Urine cells (or renal tubular cells) can be isolated from human urine samples efficiently. This noninvasive and cost-effective method to collect biological sample provide us favorable access to donor cells from human. In the present study, we generate ZZUNEUi022-A, a urine cells-derived induced pluripotent stem cell (iPSC) line, from a 29-year-old healthy male via Sendai virus delivery system. ZZUNEUi022-A showed stable karyotype, and could differentiate into three germ layers (ectoderm, mesoderm, and endoderm) readily in an embryoid body formation model.

A heterozygous MYH7 (c. 2156G > A) mutant human induced pluripotent stem cell line (ZZUNEUi020-A) generated from a patient with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a heterogeneous myocardial disease often caused by sarcomeric gene mutations. MYH7 is one of the most common genes associated with HCM. In this study, we generated a human induced pluripotent stem cell (iPSC) line ZZUNEUi020-A from peripheral blood mononuclear cells of a female HCM patient with the p. R719Q (c. 2156G > A) mutation in MYH7. This cell line expressed pluripotency markers, showed normal female karyotype and could differentiate into all three germ layers in vitro.

Induced pluripotent stem cell line (ZZUNEUi011-A) derived from peripheral blood mononuclear cells (PBMCs) of a healthy 27-year-old female individual.

In this study, we report a human induced pluripotent stem cell (iPSC) line from a healthy 27-year-old female individual using non-integrative Sendai viral reprogramming technology. The cell line expresses stemness markers, exhibits a normal female karyotype, and can differentiate into three germ layers in vivo. This iPSC line from a healthy individual provides a control group for studying disease mechanisms, drug screening, and toxicity testing.

Lysine Acetylome Study of Human Hepatocellular Carcinoma Tissues for Biomarkers and Therapeutic Targets Discovery.

Lysine acetylation is a vital post-translational modification (PTM) of proteins, which plays an important role in cancer development. In healthy human liver tissues, multiple non-histone proteins were identified with acetylation modification, however, the role of acetylated proteins in hepatocellular carcinoma (HCC) development remains largely unknown. Here we performed a quantitative acetylome study of tumor and normal liver tissues from HCC patients. Overall, 598 lysine acetylation sites in 325 proteins were quantified, and almost 59% of their acetylation levels were significantly changed. The differentially acetylated proteins mainly consisted of non-histone proteins located in mitochondria and cytoplasm, which accounted for 42% and 24%, respectively. Bioinformatics analysis showed that differentially acetylated proteins were enriched in metabolism, oxidative stress, and signal transduction processes. In tumor tissues, 278 lysine sites in 189 proteins showed decreased acetylation levels, which occupied 98% of differentially acetylated proteins. Moreover, we collected twenty pairs of tumor and normal liver tissues from HCC male patients, and found that expression levels of SIRT1 (p = 0.002), SIRT2 (p = 0.01), and SIRT4 (p = 0.045) were significantly up-regulated in tumor tissues. Over-expression of possibly accounted for the widespread deacetylation of non-histone proteins identified in HCC tumor tissues, which could serve as promising predictors of HCC. Taken together, our work illustrates abundant differentially acetylated proteins in HCC tumor tissues, and offered insights into the role of lysine acetylation in HCC development. It provided potential biomarker and drug target candidates for clinical HCC diagnosis and treatment.

SARS-CoV-2 binds platelet ACE2 to enhance thrombosis in COVID-19.

BACKGROUND: Critically ill patients diagnosed with COVID-19 may develop a pro-thrombotic state that places them at a dramatically increased lethal risk. Although platelet activation is critical for thrombosis and is responsible for the thrombotic events and cardiovascular complications, the role of platelets in the pathogenesis of COVID-19 remains unclear. METHODS: Using platelets from healthy volunteers, non-COVID-19 and COVID-19 patients, as well as wild-type and hACE2 transgenic mice, we evaluated the changes in platelet and coagulation parameters in COVID-19 patients. We investigated ACE2 expression and direct effect of SARS-CoV-2 virus on platelets by RT-PCR, flow cytometry, Western blot, immunofluorescence, and platelet functional studies in vitro, FeCl3-induced thrombus formation in vivo, and thrombus formation under flow conditions ex vivo. RESULTS: We demonstrated that COVID-19 patients present with increased mean platelet volume (MPV) and platelet hyperactivity, which correlated with a decrease in overall platelet count. Detectable SARS-CoV-2 RNA in the blood stream was associated with platelet hyperactivity in critically ill patients. Platelets expressed ACE2, a host cell receptor for SARS-CoV-2, and TMPRSS2, a serine protease for Spike protein priming. SARS-CoV-2 and its Spike protein directly enhanced platelet activation such as platelet aggregation, PAC-1 binding, CD62P expression, α granule secretion, dense granule release, platelet spreading, and clot retraction in vitro, and thereby Spike protein enhanced thrombosis formation in wild-type mice transfused with hACE2 transgenic platelets, but this was not observed in animals transfused with wild-type platelets in vivo. Further, we provided evidence suggesting that the MAPK pathway, downstream of ACE2, mediates the potentiating role of SARS-CoV-2 on platelet activation, and that platelet ACE2 expression decreases following SARS-COV-2 stimulation. SARS-CoV-2 and its Spike protein directly stimulated platelets to facilitate the release of coagulation factors, the secretion of inflammatory factors, and the formation of leukocyte-platelet aggregates. Recombinant human ACE2 protein and anti-Spike monoclonal antibody could inhibit SARS-CoV-2 Spike protein-induced platelet activation. CONCLUSIONS: Our findings uncovered a novel function of SARS-CoV-2 on platelet activation via binding of Spike to ACE2. SARS-CoV-2-induced platelet activation may participate in thrombus formation and inflammatory responses in COVID-19 patients.

An integration-free iPSC line ZZUNEUi008-A derived from dermal fibroblasts of a child with cardiac valvular dysplasia carrying a mutation in FLNA gene.

FLNA gene encodes an actin-binding protein filamin A and mutations in FLNA can causes X-Linked cardiac valvular dysplasia. In this study, we report the generation of ZZUNEUi008-A, a human induced pluripotent stem cell line from a 10-year-old male patient with c. 84G â†’ A in FLNA gene using non-integrative Sendai viral reprogramming technology. The ZZUNEUi008-A iPSC line expresses pluripotency markers, exhibits a normal male karyotype (46, XY) and can differentiate into three germ layers in vivo.

Generation of a hiPSC line ZZUNEUi007-A from a patient with hypertrophic cardiomyopathy caused by mutation in MYH7.

Hypertrophic cardiomyopathy (HCM) is the most common monogenic cardiovascular disorder. In this study, we generated human induced pluripotent stem cells (iPSC) ZZUNEUi007-A from dermal fibroblasts of an HCM patient with the p. R663H (c. 1988 G > A) mutation in MYH7. The generated hiPSC line had normal karyotype, showed robust expression of pluripotency markers and could differentiate into all three germ layers in vivo.

Generation of an IPSC line from a patient with hypertrophic cardiomyopathy carrying a mutation in MYH6 gene.

An induced pluripotent stem cell (iPSC) line was generated from peripheral blood mononuclear cells (PBMCs) of a 41-year-old male patient with hypertrophic cardiomyopathy who carries a G3755A heterozygote mutation in the MYH6 gene. The generated iPSC line expressed pluripotency markers, exhibited a normal karyotype, presented the specific mutation, and demonstrated differentiation potential into three germ layers in vitro.

Generation of a hiPSC line ZZUNEUi012-A from a healthy female individual.

Induced pluripotent stem cells (iPSCs) have differentiation potential into different somatic cell types in vitro and are a useful tool to investigate pathomechanistic and cellular processes. In this study, we generated human induced pluripotent stem cells (iPSC) ZZUNEUi012-A from an apparently healthy female individual using an integration-free reprogramming method. The generated hiPSC line was pluripotent and had normal karyotype, showed robust expression of pluripotency markers and could differentiate into all three germ layers in vitro.

Hairless controls hair fate decision via Wnt/ß-catenin signaling.

The hairless (Hr) gene plays a central role in the hair cycle, considering that mutations in the gene result in hair loss with the exception of a few vibrissae after the first hair growth cycle in both mice and humans. This study examinedthe uncommon phenotype and using microarray analyses and functional studies, we found that ß-catenin was mediated by Hr. Progenitor keratinocytes from the bulge region differentiate into both epidermis and sebaceous glands, and fail to adopt the hair keratinocytes fate in the mutant scalp, due to the decreased Wnt/ß-catenin signaling in the absence of the hairless protein. This may be attributed to the dysfunction of normal epithelial-mesenchymal interactions in the hair follicle (HF).