Project description:In order to examine the mechanism of TPO on cardiac protection against myocardial infarction damage (MI), we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to delineate the TPO cardioprotective mechanism against infarction. MI and TPO induced gene expressions in rat heart were measured at week 4. Two biological replicates were performed for each treatment group.
Project description:In order to examine the mechanism of TPO on cardiac protection against myocardial infarction damage (MI), we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to delineate the TPO cardioprotective mechanism against infarction.
Project description:In order to examine the mechanism of TPO on cardiac protection against DOX damage, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to delineate the TPO cardioprotective mechanism against DOX-induced cardiomyopathy Dox and TPO induced gene expressions in rat heart were measured at day 6. Two biological replicates were performed for each treatment group.
Project description:Thrombopoietin (TPO) was shown to prevent irradaition-induced hematopoietic stem cells (HSCs) loss of function. A single injection of TPO to mice 45-60 min prior to irradiation is sufficient to reverse the long-lasting accumulation of persistent DNA damage. We used microarrays to analyze whether this effet can relie on TPO-induced specific transcriptional changes during this early time.
Project description:Small molecular TPO mimetics, LGD-4665 and eltrombopag, were efficacious in stimulating the formation of CD41+ cells from human bone marrow CD34+ cells. To better understand the mechanism of action of TPO mimetics, a microarray study was performed to compare global gene expression in CD34+ cells induced by small molecular TPO mimetics eltrombopag and LGD4665, to changes in response to recombinant human thrombopoietin (TPO). Keywords: Drug Treatment
Project description:Normal donors BM CD34+ cells were differentiated in thrombopoietin-treated liquid suspension cultures. Briefly, CD34+ cells (80,000 /mL) were resuspended in a serum-free medium in the presence of 100 ng/mL of human recombinant thrombopoietin (TPO; Genzyme, Boston, MA). Every 3 days, viable cells were scored by Trypan blue dye exclusion and cultures were amplified with fresh serum-free medium. Each well was then supplemented with 100 ng/mL TPO. After 14 to 16 days of liquid culture, CD34-derived megakaryocytes (MKs) were purified by means of an anti-CD41a monoclonal antibody (MoAb) (Dako, Milan, Italy) directed against the glycoproteic *IIb-*3 complex and immunobeads (MPC 450 Dynabeads; Dynal, Oslo, Norway), as previously described (27). The purity of MKs was determined for each isolation by indirect immunofluorescence, using an anti-CD41b MoAb which reacts with a different epitope of *IIb-*3 subunit (Immunotech Inc., Westbrook, ME), followed by a goat anti-mouse IgG, covalently linked to fluorescein (Becton Dickinson, San Jose, CA). Essential Throbocytemia BM CD34+ cells were differentiated in thrombopoietin-treated liquid suspension cultures. Briefly, CD34+ cells (80,000 /mL) were resuspended in a serum-free medium in the presence of 100 ng/mL of human recombinant thrombopoietin (TPO; Genzyme, Boston, MA). Every 3 days, viable cells were scored by Trypan blue dye exclusion and cultures were amplified with fresh serum-free medium. Each well was then supplemented with 100 ng/mL TPO. After 14 to 16 days of liquid culture, CD34-derived megakaryocytes (MKs) were purified by means of an anti-CD41a monoclonal antibody (MoAb) (Dako, Milan, Italy) directed against the glycoproteic *IIb-*3 complex and immunobeads (MPC 450 Dynabeads; Dynal, Oslo, Norway), as previously described (27). The purity of MKs was determined for each isolation by indirect immunofluorescence, using an anti-CD41b MoAb which reacts with a different epitope of *IIb-*3 subunit (Immunotech Inc., Westbrook, ME), followed by a goat anti-mouse IgG, covalently linked to fluorescein (Becton Dickinson, San Jose, CA).
Project description:Normal donors BM CD34+ cells were differentiated in thrombopoietin-treated liquid suspension cultures. Briefly, CD34+ cells (80,000 /mL) were resuspended in a serum-free medium in the presence of 100 ng/mL of human recombinant thrombopoietin (TPO; Genzyme, Boston, MA). Every 3 days, viable cells were scored by Trypan blue dye exclusion and cultures were amplified with fresh serum-free medium. Each well was then supplemented with 100 ng/mL TPO. After 14 to 16 days of liquid culture, CD34-derived megakaryocytes (MKs) were purified by means of an anti-CD41a monoclonal antibody (MoAb) (Dako, Milan, Italy) directed against the glycoproteic *IIb-*3 complex and immunobeads (MPC 450 Dynabeads; Dynal, Oslo, Norway), as previously described (27). The purity of MKs was determined for each isolation by indirect immunofluorescence, using an anti-CD41b MoAb which reacts with a different epitope of *IIb-*3 subunit (Immunotech Inc., Westbrook, ME), followed by a goat anti-mouse IgG, covalently linked to fluorescein (Becton Dickinson, San Jose, CA). Essential Throbocytemia BM CD34+ cells were differentiated in thrombopoietin-treated liquid suspension cultures. Briefly, CD34+ cells (80,000 /mL) were resuspended in a serum-free medium in the presence of 100 ng/mL of human recombinant thrombopoietin (TPO; Genzyme, Boston, MA). Every 3 days, viable cells were scored by Trypan blue dye exclusion and cultures were amplified with fresh serum-free medium. Each well was then supplemented with 100 ng/mL TPO. After 14 to 16 days of liquid culture, CD34-derived megakaryocytes (MKs) were purified by means of an anti-CD41a monoclonal antibody (MoAb) (Dako, Milan, Italy) directed against the glycoproteic *IIb-*3 complex and immunobeads (MPC 450 Dynabeads; Dynal, Oslo, Norway), as previously described (27). The purity of MKs was determined for each isolation by indirect immunofluorescence, using an anti-CD41b MoAb which reacts with a different epitope of *IIb-*3 subunit (Immunotech Inc., Westbrook, ME), followed by a goat anti-mouse IgG, covalently linked to fluorescein (Becton Dickinson, San Jose, CA). Keywords: other
Project description:In order to examine the mechanism of TPO on cardiac protection against DOX damage, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to delineate the TPO cardioprotective mechanism against DOX-induced cardiomyopathy
Project description:The use of anthracycline antibiotics such as doxorubicin (DOX) has greatly improved the mortality and morbidity of cancer patients. However, the associated risk of cardiomyopathy has limited their clinical application. DOX-associated cardiotoxicity is irreversible and progresses to heart failure (HF). For this reason, a better understanding of the molecular mechanisms underlying these adverse cardiac effects is essential to develop improved regimes that include cardioprotective strategies. MicroRNAs (miRNAs) are short non-coding RNAs that are able to post-trascriptionally regulate gene expression. MiRNAs have been demonstrated to be involved in both cancer and cardiovascular disease. Therefore, we were interested in unveiling the potential role of miRNAs in chemotherapy-induced HF. We used a combination of three different models to recreate this cardiac toxicity (acute in vitro DOX treatment, DOX-induced HF in vivo and a myocardial infarction -MI- leading to failure model) to study the pattern of dysregulated miRNAs. Using RNA from all three conditions, miRNA microarray profiling was performed and a common miRNA signature was identified. Interestingly, these dysregulated miRNAs have been previously identified as involved in the failing heart. Our results suggest that DOX is able to alter the expression of miRNAs implicated in HF, in vitro as well as in vivo. The present study is a microRNA profiling of the damaged cardiac muscle (cardiomyocyte cell population), following either myocardial infarction (MI) induction or doxorubicin (DOX) treatment. Two DOX-treated models were included: ARC exposed to DOX in vitro and a validated DOX-induced heart failure model generated by repeated administration of DOX injections.