ObjectiveThe aim of the present study is to isolate and analyze the characterization of pericardial fluid cells (PFCs) from rat and provides a morphological basis for the basic research and clinical application of PFCs.MethodsAfter aseptic thoracotomy was performed, normal saline was injected into the pericardial cavity of 50 adult Sprague–Dawley rats. The mixture of diluted pericardial fluid was extracted, centrifuged, and cultured. The cell morphology of different generations in the pericardial fluid was observed on an inverted microscope. The expression levels of CD44, CD29, CD90, and pan-hematopoietic marker CD45 were analyzed via flow cytometry. The third-generation cells were used for osteogenic, adipogenic, and cardiac differentiation.ResultsPFCs were successfully isolated and subcultured. PFCs were predominantly circular in shape after 24 h of culture. Following subculture for 3 days, the cells demonstrated a spindle shape. The rat pericardial fluid contains cell populations with uniform morphology, good growth state, and strong proliferation ability. Flow cytometry results showed that CD29 (100%) and CD90 (99.3%) were positively expressed, whereas CD45 (0.30%) and CD44 (0.48%) were negatively expressed. The PFCs could differentiate into osteoblasts and adipocytes after being induced. Cardiac differentiation was also confirmed by cardiac troponin T (cTnT) and α-sarcomeric actin (α-SA) staining.ConclusionThis study revealed that a subpopulation of cells was isolated from pericardial fluid, which exhibited progenitor cell features and multiple differentiation potency. PFCs could serve as an alternative cell source for myocardial tissue repair, engineering, and reconstruction.

Type 1 diabetes mellitus (T1DM) is associated with an increased risk of diabetic cardiomyopathy (DCM). Nuclear factor kappa B (NF-κB) and Wnt/β-catenin/GSK3β have been demonstrated to play pathogenic roles in diabetes. In this study, we evaluated the roles of these two pathways in T1DM-induced cardiomyopathy in rats. Streptozotocin (STZ)-induced type 1 diabetic rats were treated with pyrrolidine dithiocarbamate (PDTC) or meisoindigo (Me) to inhibit NF-κB and Wnt/β-catenm/GSK3β respectively for 4 or 8 weeks. As compared with untreated diabetic rats, treatment with either PDTC or Me partly attenuated the myocardial hypertrophy and interstitial fibrosis, improved cardiac function, and exhibited reduction in inflammatory reaction. In addition, we found that inhibiting NF-κB and Wnt/β-catenin/GSK3β pathways could regulate glucose and lipid metabolism. The effects were associated with the decrease of NF-κB activity and the downregulation of some proinflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-2. Our data suggested that the activities of NF-κB and Wnt/β-catenin/GSK3β pathways were both increased and inhibiting NF-κB and Wnt/β-catenin/GSK3β signaling pathways might improve myocardial injury in T1DM rats.

Diabetic cardiomyopathy (DCM) is one of the chief diabetes mellitus complications. Inflammation factors may be one reason for the damage from DM. The purpose of this research is to study the potential protective effects of puerarin on DM and the possible mechanisms of action related to NF-κB signal pathway. Following administration of puerarin to the disease model rat, several changes were observed including the changes of serum biochemical index, improved diastolic dysfunction, and enhanced endogenous antioxidant enzymes activities, further NF-κB signaling activation. Puerarin showed cardio-protective effects on DCM by inhibiting inflammation, and it might be a potential candidate for the treatment of DCM.

Nicorandil, the first clinically applied ATP-sensitive K+ channel (K+ATP) opener with nitrate property, has demonstrated cardioprotective effects in patients with multiples of heart diseases. However, it is unknown whether nicorandil has effects on left ventricular (LV) remodeling in rats with ischemic heart failure and the potential mechanisms remain unclear. In this study, we investigated the effects of nicorandil on cardiac function, LV remodeling, and Bax expression in myocardium of LV in rats with ischemic heart failure. We found that nicorandil could improve not only the general condition, but also the cardiac function in rats with ischemic heart failure. The data also demonstrated that nicorandil reduced the hypertrophy and fibrosis of LV in rats with ischemic heart failure. Furthermore, nicorandil suppressed the protein level of Bax expression in LV myocardium. Taken together, these results suggest that nicorandil exerts its cardioprotective effect and improves LV remodeling in rats with ischemic heart failure. The mechanism might be relative to the inhibitory effect of nicorandil on the protein level of Bax expression in LV myocardium.

We propose to further research the protective effect of MMI on myocardium ischemic rat model and H9c2 cells that underwent cell apoptosis induced by hypoxia. We established the myocardium ischemic rat model via the cardiac surgical procedures in vivo and treated the model rats with different concentration of MMI. In vitro, with the pretreatment of MMI for 12 h in the model of Na2S2O4-induced hypoxia injury, the H9c2 cells viability was determined by MTT assay. We found that MMI had significantly improved cardiac function of the myocardial ischemia, and significantly decreased the reactive oxygen species level. The expression of P53, Bcl-2, Bax, and caspase-9 was also induced by MMI. In vitro study revealed a concentration-dependent increase in cell viability associated with MMI pretreatment. Annexin V-FITC and PI staining results showed that MMI had a preventive effect on hypoxia-induced apoptosis in H9c2 cells. MMI also inhibited the mitochondrial membrane potential decrease and increased total ATPase activity during hypoxia in H9c2 cells. In conclusion, MMI can enhance the cardiac function in myocardial ischemic rat and increase cell viability and attenuate the apoptosis in H9c2 cells induced by hypoxia, which was associated with inhibiting MMP decreasion and increasing total ATPase activity.

OBJECTIVE: To observe the effect of a new compound methylamine irisolidone on cardiac function in rats with experiment myocardial infarction. METHODS: The male Wistar rats were randomly divided into 6 groups: control group, ischemia model group, methylamine irisolidone preconditioning group, pretreated with different dosages of methylamine irisolidone (200,100,50 mg �� kg-1, respectively) and 200 mg �� kg-1 puerain(positive control). Coronary artery ligation was used to induce the acute myocardial ischemia model. After 30 d administration of methylamine irisolidone, the heart function parameters,including heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), left ventricular systolic pressure (LVSP), maximal velocity of increase and decrease of left ventriclar pressure (dp/dtmax), were analyzed and myocardial histology was analyzed by hematoxylin-eosin staining. RESULTS: Compared with model group, methylamine irisolidone could improve the heart function of rats in AMI injury, increased the systolic pressure and diastolic pressure, decreased the heart rate(P < 0.01). The myocardial ultrastructure injury was alleviate. CONCLUSION: Methylamine irisolidone had cardioprotective effects on acute myocardial ischemia. The mechanism may be related to slow down heart rate, prolong diastolic, so that an increase in the endocardial blood supply.