ABSTRACT: The use of tubulin binders (TBs) in oncology indications often is associated with cardiotoxicity, the mechanism of which has not been elucidated. We observed that a single administration of TBs to rats caused an increase in the number of mitotic figures in the myocardial interstitium after 24 hours. We therefore hypothesized that interstitial cells are the primary target of TBs. To test this hypothesis, we evaluated the acute effects of a single intravenous administration of 3 reference TBs, colchicine (0.2 and 2 mg/kg), vinblastine (0.5 and 3 mg/kg), and vincristine (0.1 and 1 mg/kg) 6 and 24 hours after dosing. Mitotic arrest was identified at 24 hours in all high-dose groups based on an increase in the number of mitotic figures in the interstitium coupled with a dramatic decrease in the number of Ki67-positive interstitial cells. Analysis of the myocardial transcriptomic data further supported G2/M cell cycle arrest 6 hours after dosing with the high-dose groups of all 3 compounds. Apoptotic figures and an increase in the number of cleaved caspase 3-positive cells were identified at 6 and 24 hours at the highest dose of each compound almost exclusively in interstitial cells; a few cardiomyocytes were affected as well. Transcriptomic data further suggested that some of the affected interstitial cells were endothelial cells based on the up-regulation of genes typically associated with vascular damage and down-regulation of Endothelial Cell-Specific Molecule 1 and Apelin. Taken together, these data identify endothelial cells of the myocardium as the primary target of the cardiotoxicity of TBs and identify cell cycle arrest as the mechanism of this toxicity. Gene expression was profiled in the myocardium of rats at 6 and 24 hr after a single dose of colchicine, vinblastine or vincristine.
Project description:The use of tubulin binders (TBs) in oncology indications often is associated with cardiotoxicity, the mechanism of which has not been elucidated. We observed that a single administration of TBs to rats caused an increase in the number of mitotic figures in the myocardial interstitium after 24 hours. We therefore hypothesized that interstitial cells are the primary target of TBs. To test this hypothesis, we evaluated the acute effects of a single intravenous administration of 3 reference TBs, colchicine (0.2 and 2 mg/kg), vinblastine (0.5 and 3 mg/kg), and vincristine (0.1 and 1 mg/kg) 6 and 24 hours after dosing. Mitotic arrest was identified at 24 hours in all high-dose groups based on an increase in the number of mitotic figures in the interstitium coupled with a dramatic decrease in the number of Ki67-positive interstitial cells. Analysis of the myocardial transcriptomic data further supported G2/M cell cycle arrest 6 hours after dosing with the high-dose groups of all 3 compounds. Apoptotic figures and an increase in the number of cleaved caspase 3-positive cells were identified at 6 and 24 hours at the highest dose of each compound almost exclusively in interstitial cells; a few cardiomyocytes were affected as well. Transcriptomic data further suggested that some of the affected interstitial cells were endothelial cells based on the up-regulation of genes typically associated with vascular damage and down-regulation of Endothelial Cell-Specific Molecule 1 and Apelin. Taken together, these data identify endothelial cells of the myocardium as the primary target of the cardiotoxicity of TBs and identify cell cycle arrest as the mechanism of this toxicity.
Project description:Doxorubicin (DOX) cardiotoxicity is an important factor of heart failure. The only clinically approved drug is dexrazoxane, while its side effect of secondary malignancies severely limited its application. It is urgent to find other alternative efficacious molecular for these chemotherapy patients. Colchicine is a safe and well tolerated anti-inflammation drug which also functions in attenuating the reactive oxygen species (ROS) generation. High dose of colchicine was reported block the autophagosome-lysosome fusion in cancer cells due to its destabilization effect to the microtubule system, while how colchicine affects the autophagic flux in cardiomyocytes is largely unknown. Recent years low dose of colchicine administration was reported helpful to the patients with pericarditis, postprocedural atrial fibrillation and coronary artery disease, most of the research attributed it to its anti-inflammation effect. Whether the autophagic flux regulated by colchicine also benefits to DOX induced heart failure remains unclear. Doxorubicin (DOX) administration was used to establish heart failure models in vivo and in vitro. Results showed that DOX blocked the autophagic vacuoles degradation, leading to damaged mitochondria and ROS accumulation. Heart failure characteristics were obviously improved after low dose of colchicine administration. Mechanistically, low dose of colchicine promoted the autolysosome degradation, cleared the damaged mitochondria, and ROS accumulation induced by the DOX and as a result attenuated DOX cardiotoxicity.
Project description:Objective. Colchicine is an alkaloid that is used to alleviate acute gout and to prevent acute attacks of familial Mediterranean fever (FMF). However, it is not beneficial when given during the occurrence of an acute episode of FMF. It is believed that colchicine exerts its anti-inflammatory effect through direct interaction with microtubules. We aim to study the molecular basis of colchicine action by analysing the effect of this drug on global gene expression of HUVEC (human umbilical vein endothelial cell line) cells. Methods. HUVEC cells were exposed to various concentrations of colchicine and were harvested at different time points. Ribonucleic acid was extracted, amplified, reverse transcribed and hybridized to complementary deoxyribonucleic acid microarrrays containing more than 40,000 probes to human expressed sequence tags. This approach enabled us to have a global look at the transcriptional response induced by colchicine treatment. Results. Colchicine changed the expression of many genes in HUVEC cells following exposure to a concentration of 100 ng/ml or higher. Following short exposure (30 or 120 min), colchicine affected genes known to be involved in the cell cycle and its regulation. However, change in expression of genes involved in neutrophil migration or other inflammatory processes were observed mainly after 12 to 24 h. Conclusions. The anti-inflammatory effect of colchicine may be mediated not only through direct interaction with microtubules but also through changes at the transcriptional level. This latter effect apparently requires a higher concentration and a longer time to occur. This can explain the observation that colchicine does not have an immediate effect when given during an acute attack of FMF. A dose response design type examines the relationship between the size of the administered dose and the extent of the response of the organism(s). Keywords: dose_response_design
Project description:Objective. Colchicine is an alkaloid that is used to alleviate acute gout and to prevent acute attacks of familial Mediterranean fever (FMF). However, it is not beneficial when given during the occurrence of an acute episode of FMF. It is believed that colchicine exerts its anti-inflammatory effect through direct interaction with microtubules. We aim to study the molecular basis of colchicine action by analysing the effect of this drug on global gene expression of HUVEC (human umbilical vein endothelial cell line) cells. Methods. HUVEC cells were exposed to various concentrations of colchicine and were harvested at different time points. Ribonucleic acid was extracted, amplified, reverse transcribed and hybridized to complementary deoxyribonucleic acid microarrrays containing more than 40,000 probes to human expressed sequence tags. This approach enabled us to have a global look at the transcriptional response induced by colchicine treatment. Results. Colchicine changed the expression of many genes in HUVEC cells following exposure to a concentration of 100 ng/ml or higher. Following short exposure (30 or 120 min), colchicine affected genes known to be involved in the cell cycle and its regulation. However, change in expression of genes involved in neutrophil migration or other inflammatory processes were observed mainly after 12 to 24 h. Conclusions. The anti-inflammatory effect of colchicine may be mediated not only through direct interaction with microtubules but also through changes at the transcriptional level. This latter effect apparently requires a higher concentration and a longer time to occur. This can explain the observation that colchicine does not have an immediate effect when given during an acute attack of FMF. A dose response design type examines the relationship between the size of the administered dose and the extent of the response of the organism(s). Using regression correlation
Project description:The gene expression signature of the human kidney interstitium is not fully understood. Transcript expression of laser microdissected cortical interstitium (excluding tubules, glomeruli and large vessels) in 9 human reference nephrectomies was compared to 6 human diabetic kidney biopsy specimens. This transcriptomic data revealed novel interstitial markers and enrichment of relevant pathways. Analysis of diabetic interstitium uncovered genes with unchanged as well as down-regulated expression when compared to reference samples. Laser microdissection (LMD) methodology enables collection of transcriptomic data associated with renal interstitium to aid in interpretation of pathophysiology and precision medicine studies.
Project description:The kidney contains the functional units, the nephrons, surrounded by the renal interstitium. Previously, we discovered that, once Six2-expressing nephron progenitor cells and Foxd1-expressing renal interstitial progenitor cells form at the onset of kidney development, descendant cells from these populations contribute exclusively to the main body of nephrons and renal interstitial tissues, respectively, indicating a lineage boundary between the nephron and renal interstitial compartments. Currently, it is unclear how lineages are regulated during kidney organogenesis. We demonstrate that nephron progenitor cells lacking Pax2 activity failed to differentiate into nephron cells, but can switch fates into renal interstitium cell types. These data suggest that Pax2 function maintains nephron progenitor cells by repressing transdifferentiation into renal interstitial cell states. Thus, the lineage boundary between the nephron and renal interstitial compartments is maintained by the Pax2 activity in nephron progenitor cells during kidney organogenesis.
Project description:In order to assess the descendants of lateral plate mesoderm within the muscle interstitium, we utilized Prrx1Cre;Rosa26-tdTomato P21 tdTomato+ FACS sorted muscle interstitial cells
Project description:Objective. Colchicine is an alkaloid that is used to alleviate acute gout and to prevent acute attacks of familial Mediterranean fever (FMF). However, it is not beneficial when given during the occurrence of an acute episode of FMF. It is believed that colchicine exerts its anti-inflammatory effect through direct interaction with microtubules. We aim to study the molecular basis of colchicine action by analysing the effect of this drug on global gene expression of HUVEC (human umbilical vein endothelial cell line) cells. Methods. HUVEC cells were exposed to various concentrations of colchicine and were harvested at different time points. Ribonucleic acid was extracted, amplified, reverse transcribed and hybridized to complementary deoxyribonucleic acid microarrrays containing more than 40,000 probes to human expressed sequence tags. This approach enabled us to have a global look at the transcriptional response induced by colchicine treatment. Results. Colchicine changed the expression of many genes in HUVEC cells following exposure to a concentration of 100 ng/ml or higher. Following short exposure (30 or 120 min), colchicine affected genes known to be involved in the cell cycle and its regulation. However, change in expression of genes involved in neutrophil migration or other inflammatory processes were observed mainly after 12 to 24 h. Conclusions. The anti-inflammatory effect of colchicine may be mediated not only through direct interaction with microtubules but also through changes at the transcriptional level. This latter effect apparently requires a higher concentration and a longer time to occur. This can explain the observation that colchicine does not have an immediate effect when given during an acute attack of FMF.
Project description:dataset contains 8 samples: 2 asynchronous and 2 mitotically synchronized populations (one with 90% and another with 95% mitotic purity) and 4 corresponding inputs. Cells were synchonized for 10h with colchicine at 330nM. asyncronous samples (interphase) were sonicated and prepared in parallel with same cell number as the corresponding mitotic samples. Fetal neural stem/progenitor cells were obtained from mouse telencephalon (ventral region) at E13.5. This data generated 4 genome-wide binding profiles corresponding to Brn2 (POU3f2) binding sites, aligned to MM9 mus musculus dataset.