Erythropoietin Modulates Imbalance of Matrix Metalloproteinase-2 and Tissue Inhibitor of Metalloproteinase-2 in Doxorubicin-induced Cardiotoxicity

Serine mutations in overexpressed Hsp27 abrogate the protection against doxorubicin-induced p53-dependent cardiac apoptosis in mice

Small heat shock proteins (sHsps) protect the heart from chemotherapeutics-induced heart failure by inhibiting p53-dependent apoptosis. However, mechanism of such protection has not been elucidated yet. Here we test a hypothesis that serine phosphorylation of sHsps is essential to inhibit the doxorubicin-induced and p53-dependent apoptotic pathway. Three transgenic mice (TG) lines with cardiomyocyte-specific overexpression of human heat shock protein 27 (hHsp27), namely, wild-type [myosin heavy chain (MHC)-hHsp27], S82A single mutant [MHC-mut-hHsp27(S82A)], and trimutant [MHC-mut-hHsp27(S15A/S78A/S82A)] were generated. TG mice were treated with Dox (6 mg/kg body wt; once in a week; 4 wk) along with age-matched nontransgenic (non-TG) controls. The Dox-treated MHC-hHsp27 mice showed improved survival and cardiac function (both MRI and echocardiography) in terms of contractility [ejection fraction (%EF)] and left ventricular inner diameter (LVID) compared with the Dox-treated non-TG mice. However, both MHC-mut-hHsp27(S82A) and MHC-mut-hHsp27(S15A/S78A/S82A) mutants overexpressing TG mice did not show such a cardioprotection. Furthermore, transactivation of p53 was found to be attenuated only in Dox-treated MHC-hHsp27 mice-derived cardiomyocytes in vitro, as low p53 was detected in the nuclei, not in mutant hHsp27 overexpressing cardiomyocytes. Similarly, only in MHC-hHsp27 overexpressing cardiomyocytes, low Bax, higher mechanistic target of rapamycin (mTOR) phosphorylation, and low apoptotic poly(ADP-ribose) polymerase-1 (PARP-1) cleavage (89 kDa fragment) were detected. Pharmacological inhibition of p53 was more effective in mutant TG mice compared with MHC-hHsp27 mice. We conclude that phosphorylation of overexpressed Hsp27 at S82 and its association with p53 are essential for the cardioprotective effect of overexpressed Hsp27 against Dox-induced dilated cardiomyopathy. Only phosphorylated Hsp27 protects the heart by inhibiting p53 transactivation.NEW & NOTEWORTHY Requirement of serine phosphorylation in Hsp27 for cardioprotective effect against Dox is tested in various mutants overexpressing mice. Cardioprotective effect was found to be compromised in Hsp27 serine mutants overexpressed mice compared with wild-type overexpressing mice. These results indicate that cancer patients, who carry these mutations, may have higher risk of aggravated cardiomyopathy on treated with cardiotoxic chemotherapeutics such as doxorubicin.

Keratoconus patients exhibit a distinct ocular surface immune cell and inflammatory profile

Inflammatory factors have been considered to contribute to keratoconus (KC) pathogenesis. This study aims to determine the immune cells subsets and soluble inflammatory factor profile on the ocular surface of KC patients. 32 KC subjects (51 eyes) across different grades of severity and 15 healthy controls (23 eyes) were included in the study. Keratometry and pachymetry measurements were recorded. Ocular surface immune cells (collected by ocular surface wash) immunophenotyped using flow cytometry include leukocytes, neutrophils, macrophages, natural killer (NK) cells, pan-T cells, gamma delta T (γδT) cells and NKT cells. Tear fluid collected using Schirmer's strip was used to measure 50 soluble factors by multiplex ELISA. Proportions of activated neutrophils, NK cells and γδT cells were significantly increased in KC patients. Significantly higher levels of tear fluid IL-1β, IL-6, LIF, IL-17A, TNFα, IFNα/β/γ, EPO, TGFβ1, PDGF-BB, sVCAM, sL-selectin, granzyme-B, perforin, MMP2, sFasL and IgE, along with significantly lower levels of IL-1α and IL-9 were observed in KC patients. Alterations observed in few of the immuno-inflammatory parameters correlated with grades of disease, allergy, eye rubbing and keratometry or pachymetry measurements. The observation implies a distinct immuno-inflammatory component in KC pathogenesis and its potential as an additional therapeutic target in KC management.

Pilose Antler Peptide-3.2KD Ameliorates Adriamycin-Induced Myocardial Injury Through TGF-β/SMAD Signaling Pathway

Adriamycin (ADR)-based combination chemotherapy is the standard treatment for some patients with tumors in clinical, however, long-term application can cause dose-dependent cardiotoxicity. Pilose Antler, as a traditional Chinese medicine, first appeared in the Han Dynasty and has been used to treat heart disease for nearly a thousand years. Previous data revealed pilose antler polypeptide (PAP, 3.2KD) was one of its main active components with multiple biological activities for cardiomyopathy. PAP-3.2KD exerts protective effects againt myocardial fibrosis. The present study demonstrated the protective mechanism of PAP-3.2KD against Adriamycin (ADR)-induced myocardial injury through using animal model with ADR-induced myocardial injury. PAP-3.2KD markedly improved the weight increase and decreased the HW/BW index, heart rate, and ST height in ADR-induced groups. Additionally, PAP-3.2KD reversed histopathological changes (such as disordered muscle bundles, myocardial fibrosis and diffuse myocardial cellular edema) and scores of the heart tissue, ameliorated the myocardial fibrosis and collagen volume fraction through pathological examination, significantly increased the protein level of Bcl-2, and decreased the expression levels of Bax and caspase-3 in myocardial tissue by ELISA, compared to those in ADR-induced group. Furthermore, ADR stimulation induced the increased protein levels of TGF-β1 and SMAD2/3/4, the increased phosphorylation levels of SMAD2/3 and the reduced protein levels of SMAD7. The expression levels of protein above in ADR-induced group were remarkably reversed in PAP-3.2KD-treated groups. PAP-3.2KD ameliorated ADR-induced myocardial injury by regulating the TGF-β/SMAD signaling pathway. Thus, these results provide a strong rationale for the protective effects of PAP against ADR-induced myocardial injury, when ADR is used to treat cancer.

Antioxidant Approach as a Cardioprotective Strategy in Chemotherapy-Induced Cardiotoxicity

Significance: Chemotherapy-induced cardiotoxicity (CTX) has been associated with redox signaling imbalance. In fact, redox reactions are crucial for normal heart physiology, whereas excessive oxidative stress can cause cardiomyocyte structural damage. Recent Advances: An antioxidant approach as a cardioprotective strategy in this setting has shown encouraging results in preventing anticancer drug-induced CTX. Critical Issues: In fact, traditional heart failure drugs as well as many other compounds and nonpharmacological strategies, with a partial effect in reducing oxidative stress, have been shown to counterbalance chemotherapy-induced CTX in this setting to some extent. Future Directions: Given the various pathways of toxicity involved in different chemotherapeutic schemes, interactions with redox balance need to be fine-tuned and a personalized cardioprotective approach seems to be required.

Tumor necrosis factor α, protein gene product 9.5, matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 presence in congenital intra-abdominal adhesions in children under one year of age

INTRODUCTION

The regulatory role of cytokines and extracellular matrix remodeling factors in congenital intra-abdominal adhesions has not yet been defined. The aim of this study was to assess the presence and relative distribution of tumor necrosis factor α (TNF-α), protein gene product 9.5 (PGP 9.5), matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) in adhesions.

MATERIAL AND METHODS

TNF-α, PGP 9.5, MMP-2 and TIMP-2 were detected using immunohistochemical methods and their relative distribution was evaluated by means of the semiquantitative counting method. The results were analyzed using non-parametric statistical methods.

RESULTS

A moderate number of TNF-α positive macrophages and fibroblasts was found. A positive correlation was observed between the immunoreactive structures for TNF-α and PGP 9.5. A positive reaction for PGP 9.5 was observed in nerve fibers and shape modified fibroblasts. In control group tissues, positive structures were seen in significantly higher counts for PGP 9.5. Few to moderate numbers of MMP-2 positive macrophages, epithelioid cells, fibroblasts and endotheliocytes were detected. There was no significant difference between the groups. A positive reaction for TIMP-2 was seen in fibroblasts, macrophages and endotheliocytes. In control group tissues, positive structures were found in significantly higher counts for TIMP-2.

CONCLUSIONS

The positive correlation between the immunoreactive structures for TNF-α and PGP 9.5 suggests that nerve in-growth into intraabdominal adhesions might be induced by TNF-α and PGP 9.5 could have a role in maintaining inflammation. The down-regulation of PGP 9.5 suggests that pathogenesis of congenital intraabdominal adhesions may be related to hypoxia induced damage. The imbalance between MMP-2 and TIMP-2 may prove tissue fibrosis as a response to congenital peritoneal adhesions.

The influence of erythropoietin on apoptosis and fibrosis in the early phase of chronic pancreatitis in rats

INTRODUCTION

Chronic pancreatitis (CP) is a continuing, inflammatory process of the pancreas, characterised by irreversible morphological changes. The identification of pancreatic stellate cells resulted in the development of research on the pathogenesis of CP. Erythropoietin (Epo) regulates the interaction between apoptosis and inflammation of the brain, kidney, and heart muscle. Erythropoietin receptors were also found in the pancreas, in particular on the islet cells. Our objective was to evaluate the influence of Epo on fibrosis and apoptosis in experimental CP.

MATERIAL AND METHODS

The experiments were performed on 48 male Wistar rats (250-350 g). The animals were divided into six equal groups (I - control, II - chronic cerulein - induced pancreatitis, III - 1 ml of Epo sc, IV - 0.5 ml of Epo sc, V - CP treated with 1 ml Epo, VI - CP treated with 0.5 ml Epo). The blood for gelatinases and pancreata for the morphological examinations and immunohistochemistry were collected.

RESULTS

A slight reduction of interstitial oedema and less severe fibrosis were noticed in the groups treated with Epo. Reduced expression of caspase-3 and α-actin, and a lack of Bcl-2 expression were observed in areas with inflammation. There was no expression of caspase-9 observed in all groups. There were no statistically significant differences between the groups in the activity of gelatinases.

CONCLUSIONS

Erythropoietin seems to have the effect of reducing fibrosis and apoptosis in an experimental model of CP.

Comparison of the protective effects of curcumin and caffeic acid phenethyl ester against doxorubicin-induced testicular toxicity

Whether testicular toxicity is mediated by matrix metalloproteinases (MMPs) is an important question that has not been examined. This study investigated the suppressive effect of curcumin and caffeic acid phenethyl ester (CAPE) on oxidative stress, apoptosis, and whether MMPs mediate doxorubicin (DOX)-induced testicular injury. Male rats were randomly divided into eight groups (n = 8 per group). The groups were as follows: sham, dimethyl sulphoxide (100 µL), DOX (3 mg/kg), CAPE (2.68 mg/kg), curcumin (30 mg/kg), DOX+CAPE (3 mg/kg DOX and 2.68 mg/kg CAPE), DOX+curcumin (3 mg/kg DOX and 30 mg/kg curcumin) and DOX+CAPE+curcumin (3 mg/kg DOX, 2.68 mg/kg CAPE and 30 mg/kg curcumin). Injections were administered daily for 21 days. The oxidative stress, MMPs, proinflammatory cytokines and apoptotic markers in the DOX group were higher than the sham group (p < .05); these measures were lower in the groups treated with CAPE and curcumin together with DOX compared with the DOX group (p < .05). The results showed that MMPs mediated DOX-induced testicular injury, but CAPE and especially curcumin suppressed testis injury and cell apoptosis by suppressing DOX-induced increases in MMPs, oxidative stress and proinflammatory cytokines. However, curcumin exhibited more pronounced effects than CAPE in terms of all studied parameters.

The Effects of Neuropeptide Y Overexpression on the Mouse Model of Doxorubicin-Induced Cardiotoxicity

Doxorubicin is a potent anticancer drug with cardiotoxicity hampering its use. Neuropeptide Y (NPY) is the most abundant neuropeptide in the heart and a co-transmitter of the sympathetic nervous system that plays a role in cardiac diseases. The aim of this work was to study the impact of NPY on doxorubicin-induced cardiotoxicity. Transgenic mice overexpressing NPY in noradrenergic neurons (NPY-OE^DβH) and wild-type mice were treated with a single dose of doxorubicin. Doxorubicin caused cardiotoxicity in both genotypes as demonstrated by decreased weight gain, tendency to reduced ejection fraction, and changes in the expression of several genes relevant to cardiac pathology. Doxorubicin resulted in a tendency to lower ejection fraction in NPY-OE^DβH mice more than in wild-type mice. In addition, gain in the whole body lean mass gain was decreased only in NPY-OE^DβH mice, suggesting a more severe impact of doxorubicin in this genotype. The effects of doxorubicin on genes expressed in the heart were similar between NPY-OE^DβH and wild-type mice. The results demonstrate that doxorubicin at a relatively low dose caused significant cardiotoxicity. There were differences between NPY-OE^DβH and wild-type mice in their responses to doxorubicin that suggest NPY to increase susceptibility to cardiotoxicity. This may point to the therapeutic implications as suggested for NPY system in other cardiovascular diseases.

The Morphopathogenetic Aspects of Intraabdominal Adhesions in Children under One Year of Age

Background and Objectives: The morphopathogenesis of adhesions is a complex process, characterized by the accumulation of an extracellular matrix, inflammation and hypoxia. The regulatory role between morphopathogenic factors in adhesions has not yet been defined. The aim was to investigate the appearance of transforming growth factor beta (TGFβ), basic fibroblast growth factor (FGF-2), fibroblast growth factor receptor 1 (FGFR1), protein gene product 9.5 (PGP 9.5), chromogranin A (CgA), interleukin-1 alpha (IL-1α), interleukin-4 (IL-4), interleukin-6 (IL-6), interleukin-7 (IL-7), interleukin-8 (IL-8), interleukin-10 (IL-10), tumor necrosis factor alpha (TNFα), matrix metaloproteinase-2 (MMP-2) and matrix metaloproteinase-2 tissue inhibitor (TIMP-2) in intraabdominal adhesions. Materials and Methods: The study material was obtained from 49 patients under one year of age with total or partial bowel obstruction. All factors were detected using immunohistochemistry methods and their relative distribution was evaluated by means of the semiquantitative counting method. Results: Intraabdominal adhesions are characterized by increased TGFβ, FGFR1 and decreased FGF-2, PGP 9.5, IL-1, IL-4, IL-8, TIMP-2 findings. The most significant changes observed were the remodulation of the extracellular matrix, promotion of neoangiogenesis and the maintenance of a prolonged inflammation. Conclusions: The increase in TGFβ, as well as the disbalance between MMP-2 and TIMP-2 proves an increased fibrosis in intraabdominal adhesions. Less detected FGF-2 and more prominent FGR1 findings points out a compensatory receptor stimulation in response to the lacking same factor. The decrease in PGP 9.5 indicate hypoxic injury and proves the stimulation of neoangiogenesis. An unpronounced IL-1 and marked IL-10 finding indicate the local tissue protection reaction, the decrease in IL-4 could be the direct cause of giant cells, but the decrease of IL-8 could confirm a delayed chemotaxis of inflammatory cells.

miR‑127 aggravates myocardial failure by promoting the TGF‑β1/Smad3 signaling

Myocardial failure has a negative impact on the quality of human life. MicroRNA (miR) expression abnormalities lead to the development of many pathological conditions, including myocardial failure, and therefore the present study primarily focused on the investigation of the functions of miR‑127 in the development of myocardial failure. The miR‑127 expression levels in serum samples from patients with myocardial failure were examined. Oil red O staining was used to analyze the characteristics of the myocardium of the patients. Immunohistochemistry was used to detect fatty acid synthase (FASN), stearoyl‑CoA desaturase‑1 (SCD1) and mitochondrial brown fat uncoupling protein 1 (UCP1) protein expression in the myocardium of the patients. Furthermore, C57BL/6J (B6) mice were induced with 15 mg/kg of doxorubicin. Echocardiography was used to detect the histopathological alterations of the myocardial cells by comparison of the myocardial tissues from the myocardial failure animal model and normal C57BL/6 mice. Reverse transcription‑quantitative polymerase chain reaction was used to detect the expression levels of miR‑127 following different induction periods and immunohistochemistry was used to detect the expression of transforming growth factor‑β1 (TGF‑β1) and mothers against decapentaplegic homolog 3 (Smad3). Immunofluorescence was used to detect the expression alterations TGF‑β1/Smad3 when miR‑127 overexpression or inhibition was established. The results of the present study indicated that myocardial failure resulted in an upregulated expression of miR‑127 and severe fat accumulation. FASN, SCD1 and UCP1 were highly expressed in the myocardial failure group compared with the control. Abdominal artery contraction and the ejection fraction were significantly reduced in the DOX‑induced B6 mice. The cardiomyocytes became hypertrophic, and left ventricular systolic pressure and left ventricular maximum ejection pressure were altered following DOX induction in B6 mice. The results confirmed that miR‑127 regulates the expression of TGF‑β1/Smad3. The potential pathological mechanism of the effect of miR‑127 may be based on the upregulation of the TGF‑β1/Smad3 signaling pathway.

Erythropoietin (rhEPOa) promotes endothelial transdifferentiation of stem cells of the apical papilla (SCAP)

OBJECTIVE

Mesenchymal stem cells (MSCs) have attracted worldwide attention for their capacity to repair damaged tissue, immunosuppression, ability to differentiate into several cell types and their secretome. Earlier studies have demonstrated their angiogenic potential in vitro and in vivo. However, little is known regarding pro-angiogenic inducers of stable endothelial transdifferentiation of MSCs. Here, we employed human MSCs from the Apical Papilla (SCAP) and investigated whether recombinant human erythropoietin-alpha (rhEPOa) could act as such inducer.

DESIGN

Cultured SCAP cells were exposed to rhEPOa and assessed for cell growth kinetics, viability and morphology, as well as their capacity to form capillary tubule structures in selected microenvironments. RT-PCR was used to monitor endothelial markers and activation of EPO/EPOR pathway signaling components; while gelatin zymographies to assess activation of MMP-2.

RESULTS

rhEPOa treatment initially (48 h) accelerated cell proliferation and allowed SCAP to sprout micro-tubular structures. Morphological and biochemical differentiation was accompanied by activation of MMP-2 and upregulation of PECAM-1, VEGFR2, vWF and VE-cadherin/CDH5. SCAP expressed the cognate EPO-R, while rhEPOa-treated SCAP exhibited higher expression of molecules involved in EPO/EPOR pathway (EPOR and JAK2).

CONCLUSION

rhEPOa is capable of promoting endothelial transdifferentiation of SCAP which may be of clinical value in treating of ischemic disorders.

TIMP-2 SNPs rs7342880 and rs4789936 are linked to risk of knee osteoarthritis in the Chinese Han Population

This study aimed to investigate whether functional polymorphisms in the tissue inhibitors of metalloproteinase-2 (TIMP-2) gene are associated with susceptibility to knee osteoarthritis (OA) in the Chinese Han population. Six TIMP-2 single nucleotide polymorphisms (SNPs) were assayed using MassARRAY in 300 patients clinically and radiographically diagnosed with knee OA and in 428 controls. Allelic and genotypic frequencies were compared between groups. Logistic regression adjusting for age and gender was used to estimate risk associations between specific genotypes and knee OA by computing odds ratios (ORs) and 95% confidence intervals (95% CIs). We found that allele "A" in rs7342880 was significantly associated with increased risk of knee OA (OR = 1.44, 95%CI = 1.09-1.91, p = 0.035). In addition, in the over-dominant model, rs4789936 correlated with reduced risk of knee OA, adjusting for age and gender (OR = 0.69, 95%CI = 0.49-0.98, p = 0.036). Finally, rs7342880 correlated with increased risk of knee OA in females. This study provides evidence that TIMP-2 is a knee OA susceptibility gene in the Chinese population and a potential diagnostic and preventive marker for the disease.

Effect of low intensity pulsed ultrasound on expression of TIMP-2 in serum and expression of mmp-13 in articular cartilage of rabbits with knee osteoarthritis

OBJECTIVE

To study the effect of low intensity pulsed ultrasound (LIPUS) on the expression of tissue inhibitor of metalloproteinase-2 (TIMP-2) in the serum and expression of matrix metallopeptidase 13 (MMP-13) in the articular cartilage cells of rabbits with knee osteoarthritis (OA).

METHODS

Inner patellar ligament defect method was used to establish the model of knee OA. Four weeks after the modeling, the arterial blood was drawn from the ear of each rabbit, while ELISA was employed to detect the expression of TIMP-2 in the serum. The chondrocytes were separated from animals in each group and then cultured in vitro. All rabbits were divided into control group, OA model group and OA + LIPUS group. Cells in the control and OA groups were not treated, while cells in the OA + LIPUS group were treated with LIPUS (40 mW/cm(2), 1 time/day). Cells were collected 7 d later and the RNA and total protein were extracted respectively. Real-time PCR and Western blotting were employed to analyze the expression of MMP-13 in chondrocytes at the mRNA and protein level, respectively.

RESULTS

The success rate of establishment of OA model was 83%. The results of ELISA showed that the content of TIMP-2 in the serum of animals with OA was 22.3%, lower than the one in the control group (P < 0.05). Compared with the normal control group, the expression of TIMP-2 in the OA model group was significantly increased, while the expression of MMP-13 was significantly increased (P < 0.05). After the stimulation of LIPUS, the expression of TIMP-2 and MMP-13 was close to the one in the normal control group.

CONCLUSIONS

The inner patellar ligament defect method is a mature method to establish the rabbit OA model, with high success rate. The expression of serum TIMP-2 in the OA model group is significantly decreased. LIPUS can up-regulate TIMP-2 and down-regulate MMP-13.

Erythropoietin Decreases the Occurrence of Myocardial Fibrosis by Inhibiting the NADPH-ERK-NF-x03BA;B Pathway

OBJECTIVES

The aim of this study was to investigate the protective role of erythropoietin (EPO) against myocardial fibrosis (MF).

METHODS

Pressure-overloaded rats were established by abdominal aortic constriction, the rats were randomly divided in a double-blind manner into 3 groups (n = 12 for each group): sham-operated rats (sham), operated rats receiving physiological saline (vehicle) and operated rats receiving 4,000 U/kg rhEPO (EPO group). The vehicle and drugs were administered to rats by intraperitoneal injection. In addition, cultured adult rat cardiac fibroblasts (CFs) were utilized to investigate the role of EPO in CF proliferation and collagen secretion.

RESULTS

After 4 weeks, besides an increase in blood pressure, myocardial hypertrophy, collagen deposition in the myocardium and decreased cardiac function were observed in the pressure-overloaded rats. The expression of NADPH oxidase (Nox2 and Nox4) and inflammatory cytokines (CD45, F4/80 and MCP-1) was also significantly increased. All these alterations were prevented by EPO. TGF-β promoted CF proliferation, collagen secretion, ROS production and Nox2/Nox4 expression, which was inhibited by EPO. In addition, the TGF-β-induced increase of ERK1/2 phosphorylation and NF-x03BA;B expression were attenuated by EPO.

CONCLUSION

EPO inhibited rat MF induced by pressure overload and improved myocardial function by decreasing CF proliferation and differentiation via inhibition of the NADPH-ERK-NF-x03BA;B pathway.

Recombinant Human Erythropoietin Protects Myocardial Cells from Apoptosis via the Janus-Activated Kinase 2/Signal Transducer and Activator of Transcription 5 Pathway in Rats with Epilepsy

OBJECTIVE

To investigate the potential mechanisms underlying the protective effects of recombinant human erythropoietin (rhEPO) and carbamylated EPO (CEPO) against myocardial cell apoptosis in epilepsy.

METHODS

Rats were given an intra-amygdala injection of kainic acid to induce epilepsy. Groups of rats were treated with rhEPO or CEPO before induction of epilepsy, whereas additional rats were given a caudal vein injection of AG490, a selective inhibitor of Janus kinase 2 (JAK2). At different time points after seizure onset, electroencephalogram changes were recorded, and myocardium samples were taken for the detection of myocardial cell apoptosis and expression of JAK2, signal transducer and activator of transcription 5 (STAT5), caspase-3, and bcl-xl mRNAs and proteins.

RESULTS

Induction of epilepsy significantly enhanced myocardial cell apoptosis and upregulated the expression of caspase-3 and bcl-xl proteins and JAK2 and STAT5a at both the mRNA and protein levels. Pretreatment with either rhEPO or CEPO reduced the number of apoptotic cells, upregulated bcl-xl expression, and downregulated caspase-3 expression in the myocardium of epileptic rats. Both myocardial JAK2 and STAT5a mRNAs, as well as phosphorylated species of JAK2 and STAT5a, were upregulated in epileptic rats in response to rhEPO-but not to CEPO-pretreatment. AG490 treatment increased apoptosis, upregulated caspase-3 protein expression, and downregulated bcl-xl protein expression in the myocardium of epileptic rats.

CONCLUSIONS

These results indicate that myocardial cell apoptosis may contribute to myocardial injury in epilepsy. EPO protects myocardial cells from apoptosis via the JAK2/STAT5 pathway in rats with experimental epilepsy, whereas CEPO exerts antiapoptotic activity perhaps via a pathway independent of JAK2/STAT5 signaling.