Bone marrow mononuclear cells enhance anti-inflammatory effects of pravastatin against isoproterenol-induced myocardial infarction in rats

Pravastatin attenuates isoprenaline induced cardiac fibrosis in a mouse model

We investigated the effects of pravastatin (PRAVA) on isoprenaline (ISP) induced cardiac fibrosis using four groups of mice: untreated control, PRAVA, ISP, ISP + PRAVA groups. ISP, 20 mg/kg, was administered subcutaneously daily for 14 days. PRAVA, 20 mg/kg, was administered orally daily for 14 days. Mice were sacrificed on day15 and heart and blood samples were collected to investigate cardiac injury markers. The mean body weight for the ISP group on day 15 was decreased significantly compared to day 0; PRAVA increased the mean body weight slightly on day 15 of treatment compared to day 0. The heart:body weight ratio was increased in the ISP group compared to the control group, but the ratio was returned to near control ratio in the PRAVA + ISP group. The serum creatine kinase-myocardial band (CK-MB) level was reduced significantly in the PRAVA + ISP group compared to the ISP group. Serum triglyceride level was decreased significantly in ISP + PRAVA group compared to the ISP group. PRAVA administration significantly reduced tissue collagen I and III levels in the ISP + PRAVA group compared to the ISP group. Lipid oxidation was decreased and reduced glutathione activity was increased in the PRAVA + ISP group compared to the ISP group. IL-6, α-SMA, CTGF, TGF-β and SMAD-3 gene expressions were decreased in the PRAVA + ISP group compared to the ISP group. We found fewer inflammatory cells and less fibrosis in heart tissue in the PRAVA + ISP group compared to the ISP group. PRAVA decreased ISP induced cardiac fibrosis by reducing oxidative stress, collagen deposition and inflammation, as well as by decreasing expression of TGF-β, SMAD-3 and CTGF genes.

Beneficial Modulatory Effects of Treatment With Bone Marrow Lysate on Hematopoietic Stem Cells and Myeloid Cells in Tumor-Bearing Mice

Introduction: Leukopenia is one of the major side effects of myelosuppressive chemotherapy such as cyclophosphamide (CTX). We and others have used CTX either alone or in combination with G-CSF for the mobilization of hematopoietic stem cells (HSCs). This mobilization can induce expansion of myeloid cells with immunosuppressive phenotype. In this pilot study, we aimed to test whether bone marrow lysate (BML)/CTX, a rich source of growth factors, can lower the expansion of myeloid cells with immunosuppressive phenotypes in tumor-bearing mice without interfering with the anti-tumor effects of CTX or with the mobilization of HSCs. Methods: Female CD1 mice were treated on day 0 with an i.p. injection of Ehrlich ascites carcinoma (EAC). On day 7, the mice were i.p. injected with CTX followed by s.c. injection of G-CSF for 5 consecutive days, single s.c. injection of BML/PBS or BML/CTX or single i.v. injection of BMC/PBS or BMC/CTX. Results: Treatment of EAC-bearing mice with BML/PBS or BML/CTX did not interfere with the anti-tumor effect of CTX. EAC increased the numbers of immature polymorphonuclear cells (iPMN; neutrophils) in both blood and spleen. Treatment of EAC-bearing mice with CTX further increased the numbers of these cells, which were decreased upon treatment with BML/CTX. Treatment with BML/PBS or BML/CTX increased the numbers of stem cells (C.Kit+Sca-1+) in BM; the effect of BML/CTX was higher, but with no significant effect on the numbers of HSCs. Future studies are needed to analyze the molecular components in BM lysate and to determine the underlying mechanisms.

Effects of pinealectomy and crocin treatment on rats with isoproterenol-induced myocardial infarction

The present study aimed to analyze the effects of pinealectomy and crocin treatment in isoproterenol-induced myocardial damage. Seventy rats were divided into seven groups: control, sham control, pinealectomy (PNX), isoproterenol (ISO; 85 mg/kg on the 29th and 30th days of the experiment, subcutaneous injection), PNX + ISO, PNX + crocin (50 mg/kg/day for 30 days, intragastric administration), and PNX + ISO + crocin. PNX procedure was performed on the first day of the study. A significant increase was observed in serum cardiac damage markers (CK-MB, Troponin I) after ISO administration. ISO administration led to a significant increase in cardiac oxidative stress parameters, such as malondialdehyde (MDA) and total oxidant status (TOS), while it led to a decrease in antioxidant defense system parameters, such as reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and total antioxidant status (TAS) when compared to control groups. Elevated MDA and TOS levels were observed, while reduced SOD and CAT activities, and decreased GSH and TAS levels were observed in the group that underwent PNX and ISO administration when compared to the PNX group. Furthermore, in the PNX + ISO + Crocin group, SOD and CAT activities, and GSH and TAS levels ameliorated and MDA and TOS levels were reduced with the crocin treatment when compared to the PNX + ISO group. Also, marked increases were observed in serum cardiac markers, histopathological and immunohistochemical findings after the crocin treatment. All findings demonstrated that crocin could be employed as a cardioprotective agent due to its antioxidant, anti-inflammatory, and anti-apoptotic properties.

Comparative mRNA and MicroRNA Profiling during Acute Myocardial Infarction Induced by Coronary Occlusion and Ablation Radio-Frequency Currents

The ligation of the left anterior descending coronary artery is the most commonly used experimental model to induce myocardial infarction (MI) in rodents. A high mortality in the acute phase and the heterogeneity of the size of the MI obtained are drawbacks recognized in this model. In an attempt to solve the problem, our group recently developed a new MI experimental model which is based on application of myocardial ablation radio-frequency currents (AB-RF) that yielded MI with homogeneous sizes and significantly reduce acute mortality. In addition, cardiac structural, and functional changes aroused by AB-RF were similar to those seen in animals with MI induced by coronary artery ligation. Herein, we compared mRNA expression of genes that govern post-MI milieu in occlusion and ablation models. We analyzed 48 mRNAs expressions of nine different signal transduction pathways (cell survival and metabolism signs, matrix extracellular, cell cycle, oxidative stress, apoptosis, calcium signaling, hypertrophy markers, angiogenesis, and inflammation) in rat left ventricle 1 week after MI generated by both coronary occlusion and AB-RF. Furthermore, high-throughput miRNA analysis was also assessed in both MI procedures. Interestingly, mRNA expression levels and miRNA expressions showed strong similarities between both models after MI, with few specificities in each model, activating similar signal transduction pathways. To our knowledge, this is the first comparison of genomic alterations of mRNA and miRNA contents after two different MI procedures and identifies key signaling regulators modulating the pathophysiology of these two models that might culminate in heart failure. Furthermore, these analyses may contribute with the current knowledge concerning transcriptional and post-transcriptional changes of AB-RF protocol, arising as an alternative and effective MI method that reproduces most changes seem in coronary occlusion.