Autologous bone marrow-derived mononuclear cell therapy prevents the damage of viable myocardium and improves rat heart function following acute anterior myocardial infarction

The application of extracorporeal shock wave therapy on stem cells therapy to treat various diseases

In the last ten years, stem cell (SC) therapy has been extensively used to treat a range of conditions such as degenerative illnesses, ischemia-related organ dysfunction, diabetes, and neurological disorders. However, the clinical application of these therapies is limited due to the poor survival and differentiation potential of stem cells (SCs). Extracorporeal shock wave therapy (ESWT), as a non-invasive therapy, has shown great application potential in enhancing the proliferation, differentiation, migration, and recruitment of stem cells, offering new possibilities for utilizing ESWT in conjunction with stem cells for the treatment of different systemic conditions. The review provides a detailed overview of the advances in using ESWT with SCs to treat musculoskeletal, cardiovascular, genitourinary, and nervous system conditions, suggesting that ESWT is a promising strategy for enhancing the efficacy of SC therapy for various diseases.

Stem Cell Therapy against Ischemic Heart Disease

Ischemic heart disease, which is one of the top killers worldwide, encompasses a series of heart problems stemming from a compromised coronary blood supply to the myocardium. The severity of the disease ranges from an unstable manifestation of ischemic symptoms, such as unstable angina, to myocardial death, that is, the immediate life-threatening condition of myocardial infarction. Even though patients may survive myocardial infarction, the resulting ischemia-reperfusion injury triggers a cascade of inflammatory reactions and oxidative stress that poses a significant threat to myocardial function following successful revascularization. Moreover, despite evidence suggesting the presence of cardiac stem cells, the fact that cardiomyocytes are terminally differentiated and cannot significantly regenerate after injury accounts for the subsequent progression to ischemic cardiomyopathy and ischemic heart failure, despite the current advancements in cardiac medicine. In the last two decades, researchers have realized the possibility of utilizing stem cell plasticity for therapeutic purposes. Indeed, stem cells of different origin, such as bone-marrow- and adipose-derived mesenchymal stem cells, circulation-derived progenitor cells, and induced pluripotent stem cells, have all been shown to play therapeutic roles in ischemic heart disease. In addition, the discovery of stem-cell-associated paracrine effects has triggered intense investigations into the actions of exosomes. Notwithstanding the seemingly promising outcomes from both experimental and clinical studies regarding the therapeutic use of stem cells against ischemic heart disease, positive results from fraud or false data interpretation need to be taken into consideration. The current review is aimed at overviewing the therapeutic application of stem cells in different categories of ischemic heart disease, including relevant experimental and clinical outcomes, as well as the proposed mechanisms underpinning such observations.

AhR-STAT3-HO-1/COX-2 signalling pathway may restrict ferroptosis and improve hMSC accumulation and efficacy in mouse liver

BACKGROUND AND PURPOSE

The low efficacy of mesenchymal stem cells (MSCs) has restricted their application in the treatment of liver disease. Emerging evidence suggested that ferroptosis may provoke hepatocyte dysfunction and exacerbate damage to the liver microenvironment. Here, we have investigated the contribution of liver ferroptosis to the elimination and effectiveness of human MSC (hMSC). Furthermore, potential links between liver ferroptosis and aryl hydrocarbon receptors (AhR) were explored.

EXPERIMENTAL APPROACH

Two mouse models, iron supplement-induced hepatic ferroptosis and hepatic ischaemia/reperfusion (I/R) injury, were used to identify effects of ferroptosis on hMSC pharmacokinetics (PK)/pharmacodynamics (PD).

KEY RESULTS

AhR inhibition attenuated hepatic ferroptosis and improved survival of hMSCs. hMSC viability was decreased by iron supplementation or serum from I/R mice. The AhR antagonist CH223191 reversed iron overload and oxidative stress induced by ferroptosis and increased hMSC concentration and efficacy in mouse models. Effects of CH223191 were greater than those of deferoxamine, a conventional ferroptosis inhibitor. Transcriptomic results suggested that the AhR-signal transducer and activator of transcription 3 (STAT3)-haem oxygenase 1/COX-2 signalling pathway is critical to this process. These results were confirmed in a mouse model of hepatic I/R injury. In mice pre-treated with CH223191, hMSC exhibited more potent protective effects, linked to decreased hepatic ferroptosis.

CONCLUSION AND IMPLICATIONS

Our findings showed that ferroptosis was a critical factor in determining the fate of hMSCs. Inhibition of AhR decreased hepatic ferroptosis, thereby increasing survival and therapeutic effects of hMSCs in mouse models of liver disease.

Mesenchymal stem cells seeded onto nanofiber scaffold for myocardial regeneration

Cardiac disease is the leading cause of mortality and disability worldwide. We investigated the role of undifferentiated adipose tissue-derived mesenchymal stem cells (ADMSC) alone and ADMSC seeded onto the electro-spun nanofibers (NF) for reconstructing damaged cardiac tissue in isoprenaline-induced myocardial infarction (MI) in rats. ADMSC were sorted by morphological appearance and by detection of cluster of differentiation (CD) surface antigens. The therapeutic potential of ADMSC for treating MI was evaluated by electrocardiogram (ECG), biochemical analysis, molecular genetic analysis and histological examination. Treatment of MI-challenged rats with ADMSC improved ECG findings, which were corroborated by significant decreases in serum lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) enzyme activities together with reduced serum troponin T (cTnT) and connexin 43 (Cx43) levels. MI model rats treated with ADMSC exhibited a significant increase in serum alpha sarcomeric actin (Actn) and GATA binding protein 4 (GATA4), and NK2 homeobox 5 (NKX2.5) gene expression was decreased following treatment with ADMSC. ADMSC also ameliorated damage to cardiac tissue. The effects of ADMSC seeded onto NF were superior to those of ADMSC alone. ADMSC may be useful for mitigation of MI.

Preclinical efficacy of stem cell therapy for skin flap: a systematic review and meta-analysis

Background

A skin flap is one of the most critical surgical techniques for the restoration of cutaneous defects. However, the distal necrosis of the skin flap severely restricts the clinical application of flap surgery. As there is no consensus on the treatment methods to prevent distal necrosis of skin flaps, more effective and feasible interventions to prevent skin flaps from necrosis are urgently needed. Stem therapy as a potential method to improve the survival rate of skin flaps is receiving increasing attention.

Methods

This review followed the recommendations from the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statements. Twenty studies with 500 animals were included by searching Web of Science, EMBASE, PubMed, and Cochrane Library databases, up until October 8, 2020. Moreover, the references of the included articles were searched manually to obtain other studies. All analyses were conducted using Review Manager V.5.3 software.

Results

Meta-analysis of all 20 studies demonstrated stem cell treatment has significant effects on reducing necrosis of skin flap compared with the control group (SMD: 3.20, 95% CI 2.47 to 3.93). Besides, subgroup analysis showed differences in the efficacy of stem cells in improving the survival rate of skin flaps in areas of skin flap, cell type, transplant types, and method of administration of stem cells. The meta-analysis also showed that stem cell treatment had a significant effect on increasing blood vessel density (SMD: 2.96, 95% CI 2.21 to 3.72) and increasing the expression of vascular endothelial growth factor (VEGF, SMD: 4.34, 95% CI 2.48 to 6.1).

Conclusions

The preclinical evidence of our systematic review indicate that stem cell-based therapy is effective for promoting early angiogenesis by up regulating VEGF and ultimately improving the survival rate of skin flap. In summary, small area skin flap, the administration method of intra-arterial injection, ASCs and MSCs, and xenogenic stem cells from humans showed more effective for the survival of animal skin flaps. In general, stem cell-based therapy may be a promising method to prevent skin flap necrosis.

Losing Regulation of the Extracellular Matrix is Strongly Predictive of Unfavorable Prognostic Outcome after Acute Myocardial Infarction

This study tested the hypothesis that MMP-9^-/-tPA^-/- double knock out (i.e., MT^DKO) plays a crucial role in the prognostic outcome after acute myocardial infarction (AMI by ligation of left-coronary-artery) in MT^DKO mouse. Animals were categorized into sham-operated controls in MT^DKO animals (group 1) and in wild type (B6: group 2), AMI-MT^DKO (group 3) and AMI-B6 (group 4) animals. They were euthanized, and the ischemic myocardium was harvested, by day 60 post AMI. The mortality rate was significantly higher in group 3 than in other groups and significantly higher in group 4 than in groups 1/2, but it showed no difference in the latter two groups (all p < 0.01). By day 28, the left-ventricular (LV) ejection fraction displayed an opposite pattern, whereas by day 60, the gross anatomic infarct size displayed an identical pattern of mortality among the four groups (all p < 0.001). The ratio of heart weight to tibial length and the lung injury score exhibited an identical pattern of mortality (p < 0.01). The protein expressions of apoptosis (mitochondrial-Bax/cleaved-caspase3/cleaved-PARP), fibrosis (Smad3/T-GF-ß), oxidative stress (NOX-1/NOX-2/oxidized-protein), inflammation (MMPs^2,9/TNF-α/p-NF-κB), heart failure/pressure overload (BNP/ß-MHC) and mitochondrial/DNA damage (cytosolic-cytochrome-C/γ-H2AX) biomarkers displayed identical patterns, whereas the angiogenesis markers (small vessel number/CD31+cells in LV myocardium) displayed opposite patterns of mortality among the groups (all p < 0.0001). The microscopic findings of fibrotic/collagen deposition/infarct areas and inflammatory cell infiltration of LV myocardium were similar to the mortality among the four groups (all p < 0.0001). MT^DKO strongly predicted unfavorable prognostic outcome after AMI.

Intra-carotid arterial transfusion of circulatory-derived autologous endothelial progenitor cells in rodent after ischemic stroke-evaluating the impact of therapeutic time points on prognostic outcomes

Background

This study tested the optimal time point for left intra-carotid arterial (LICA) administration of circulatory-derived autologous endothelial progenitor cells (EPCs) for improving the outcome in rat after acute ischemic stroke (IS).

Methods and results

Adult male SD rats (n = 70) were equally categorized into group 1 (sham-operated control), group 2 (IS), group 3 (IS+EPCs/1.2 × 10⁶ cells/by LICA administration 3 h after IS), group 4 (IS+EPCs/LICA administration post-day-3 IS), group 5 (IS+EPCs/LICA administration post-day-7 IS), group 6 (IS+EPCs/LICA administration post-day-14 IS), and group 7 (IS+EPCs/LICA administration post-day-28 IS). The brain infarct volume (BIV) (at day 60/MRI) was lowest in group 1, highest in group 2, and significantly progressively increased from groups 3 to 7, whereas among the IS animals, the neurological function was significantly preserved in groups 3 to 6 than in groups 2 and 7 post-day-60 IS (all P < 0.0001). By day 60, the endothelial cell markers at protein and cellular levels and number of small vessels exhibited an opposite pattern of BIV among the groups (all P < 0.0001). The protein and cellular levels of inflammation, and protein levels of oxidative stress, autophagy, and apoptosis were highest in group 2, lowest in group 1, and progressively increased from groups 3 to 7 (all P < 0.0001). The angiogenesis biomarkers at protein and cellular levels were significantly progressively increased from groups 1 to 3, then significantly progressively decreased from groups 4 to 7 (all P < 0.0001).

Conclusion

Early EPC administration provided better benefits on improving functional/image/molecular-cellular outcomes after acute IS in rat.

Adipose-derived mesenchymal stem cells attenuate ischemic brain injuries in rats by modulating miR-21-3p/MAT2B signaling transduction

Aim

To explore the mechanism underlying the protective effect of adipose-derived mesenchymal stem cells (ADMSCs) against ischemic stroke by focusing on miR-21-3p/MAT2B axis.

Methods

Ischemic brain injury was induced in 126 rats by middle cerebral artery occlusion (MCAO). The effect of ADMSC administration on blood-brain barrier (BBB) condition, apoptosis, inflammation, and the activity of miR-21-3p/MAT2B axis was assessed. The role of miR-21-3p inhibition in the function of ADMSCs was further validated in in vitro neural cells.

Results

ADMSCs administration improved BBB condition, inhibited apoptosis, and suppressed inflammation. It also reduced the abnormally high level of miR-21-3p in MCAO rats. Dual luciferase assays showed that miR-21-3p directly inhibited the MAT2B expression in neural cells, and miR-21-3p inhibition by inhibitor or ADMSC-derived exosomes in neurons attenuated hypoxia/reoxygenation-induced impairments similarly to that of ADMSCs in vivo.

Conclusion

This study confirmed the protective effect of ADMSCs against ischemic brain injury exerted by suppressing miR-21-3p level and up-regulating MAT2B level.

Hypoxic Preconditioned Mesenchymal Stromal Cell Therapy in a Rat Model of Renal Ischemia-reperfusion Injury: Development of Optimal Protocol to Potentiate Therapeutic Efficacy

Although previous and ongoing clinical studies have used stromal cells during renal ischemia-reperfusion injury (IRI), there is little consensus regarding the optimal protocol. We aimed to optimize the protocol for hypoxic preconditioned human bone marrow-derived mesenchymal stromal cell (HP-hBMSC) therapy in a rat model of renal IRI. We determined the optimal injection route (renal arterial, renal parenchymal, and tail venous injection), dose (low-dose: 1×10⁶, moderate-dose: 2×10⁶, and high-dose: 4×10⁶), and injection period (pre-, concurrent-, and post-IRI). During optimal injection route study, renal arterial injections significantly reduced the decreasing glomerular filtration rate (GFR), as compared to GFRs for the IRI control group, 2 and 4 days after IRI. Therapeutic effects and histological recoveries were the greatest in the group receiving renal arterial injections. During the dose finding study, high-dose injections significantly reduced the decreasing GFR, as compared to GFRs for the IRI control group, 3 days after IRI. Therapeutic effects and histological recoveries were the greatest in the high-dose injection group. While determining the optimal injection timing study, concurrent-IRI injection reduced elevated serum creatinine levels, as compared to those of the IRI control group, 1 day after IRI. Pre-IRI injection significantly reduced the decreasing GFR, as compared with GFRs for the IRI control group, 1 day after IRI. Therapeutic effects and histological recoveries were the greatest in the concurrent-IRI group. In conclusion, the concurrent-IRI administration of a high dose of HP-hBMSC via the renal artery leads to an optimal recovery of renal function after renal IRI.

Extracorporeal Shock Wave-Supported Adipose-Derived Fresh Stromal Vascular Fraction Preserved Left Ventricular (LV) Function and Inhibited LV Remodeling in Acute Myocardial Infarction in Rat

This study tested the hypothesis that extracorporeal shock wave- (ECSW-) assisted adipose-derived stromal vascular fraction (SVF) therapy could preserve left ventricular ejection fraction (LVEF) and inhibit LV remodeling in a rat after acute myocardial infarction (AMI). Adult male SD rats were categorized into group 1 (sham control), group 2 (AMI induced by left coronary artery ligation), group 3 [AMI + ECSW (280 impulses at 0.1 mJ/mm², applied to the chest wall at 3 h, days 3 and 7 after AMI), group 4 [AMI + SVF (1.2 × 10⁶) implanted into the infarct area at 3 h after AMI], and group 5 (AMI + ECSW-SVF). In vitro, SVF protected H9C2 cells against menadione-induced mitochondrial damage and increased fluorescent intensity of mitochondria in nuclei (p < 0.01). By day 42 after AMI, LVEF was highest in group 1, lowest in group 2, significantly higher in group 5 than in groups 3 and 4, and similar between the latter two groups (all p < 0.0001). LV remodeling and infarcted, fibrotic, and collagen deposition areas as well as apoptotic nuclei exhibited an opposite pattern to LVEF among the groups (all p < 0.0001). Protein expressions of CD31/vWF/eNOS/PGC-1α/α-MHC/mitochondrial cytochrome C exhibited an identical pattern, whilst protein expressions of MMP-9/TNF-α/IL-1β/NF-κB/caspase-3/PARP/Samd3/TGF-β/NOX-1/NOX-2/oxidized protein/β-MHC/BNP exhibited an opposite pattern to LVEF among five groups (all p < 0.0001). Cellular expressions of CXCR4/SDF-1α/Sca-1/c-Kit significantly and progressively increased from groups 1 to 5 (all p < 0.0001). Cellular expression of γ-H2AX/CD68 displayed an opposite pattern to LVEF among the five groups (all p < 0.0001). In conclusion, ECSW-SVF therapy effectively preserved LVEF and inhibited LV remodeling in rat AMI.

Recovery of renal function after administration of adipose-tissue-derived stromal vascular fraction in rat model of acute kidney injury induced by ischemia/reperfusion injury

Acute kidney injury (AKI) induced by ischemia/reperfusion (I/R) injury is a major challenge in critical care medicine. The purpose of this study is to determine the therapeutic effects of the adipose-tissue-derived stromal vascular fraction (SVF) and the optimal route for SVF delivery in a rat model of AKI induced by I/R injury. Fifty male Sprague-Dawley rats were randomly divided into five groups (10 animals per group): sham, nephrectomy control, I/R injury control, renal arterial SVF infusion and subcapsular SVF injection. To induce AKI by I/R injury, the left renal artery was clamped with a nontraumatic vascular clamp for 40 min, and the right kidney was removed. Rats receiving renal arterial infusion of SVF had a significantly reduced increase in serum creatinine compared with the I/R injury control group at 4 days after I/R injury. The glomerular filtration rate of the renal arterial SVF infusion group was maintained at a level similar to that of the sham and nephrectomy control groups at 14 days after I/R injury. Masson's trichrome staining showed significantly less fibrosis in the renal arterial SVF infusion group compared with that in the I/R injury control group in the outer stripe (P < 0.001). TUNEL labeling showed significantly decreased apoptosis in both the renal arterial SVF infusion and subcapsular SVF injection groups compared with the I/R injury control group in the outer stripe (P < 0.001). Thus, renal function is effectively rescued from AKI induced by I/R injury through the renal arterial administration of SVF in a rat model.

Melatonin enhances survival and preserves functional integrity of stem cells: A review

Despite state-of-the-art pharmaceutical regimens, continuous improvements in diagnostic techniques as well as refinements in equipment and interventional procedures, many diseases remain refractory to conventional therapies. Recent advances in stem cell (SC) biology have opened an avenue to exploring its therapeutic potential in various disease entities, especially those that are ischemia-related and refractory to conventional treatment. A number of experimental studies and clinical trials have already demonstrated promising outcomes. On the other hand, SC therapy is associated with major problems. For instance, ischemia, inflammation, and oxidative stress are some of the factors unfavorable for SC survival once SCs are implanted into the ischemic area in an attempt to enhance tissue regeneration and restore organ function. Melatonin, which is originally derived from pineal gland in the regulation of human circadian rhythms and sleep, is a potent free radical scavenger and metal chelator with the capacity to alleviate oxidative stress and inflammatory reactions as well as stabilizing cell membranes. Accumulating data have demonstrated that melatonin-supported SC therapy is superior to SC alone for improving ischemia-related organ dysfunction. In this review, we describe and interpret the potential role of melatonin in sustaining the survival and preserving the functional integrity of SC.

Huoxue Anxin Recipe () promotes myocardium angiogenesis of acute myocardial infarction rats by up-regulating miR-210 and vascular endothelial growth factor

OBJECTIVE

To investigate the microRNAs (miRNAs) expression profile of acute myocardial infarction (AMI) rats and the regulating effects of Huoxue Anxin Recipe (, HAR) on angiogenesis-related miRNAs and genes.

METHODS

Forty-five Wistar rats were randomly assigned to 3 groups according to a random number table: sham, AMI, and AMI+HAR groups (15 in each group). AMI rats were established by ligation of the left descending coronary artery. HAR was intragastrically administered to rats of the AMI+HAR group for successive 21 days since modeling, meanwhile the same volume of 0.9% normal saline was administered to rats of the sham and AMI groups. Doppler echocardiography was used for noninvasive cardiac function test. Hematoxylin and eosin staining was used to observe the histopathological change. miRNAs expression profile was detected by quantitative realtime polymerase chain reaction (qRT-PCR). The mRNA and protein expressions of vascular endothelial growth factor (VEGF), and a target gene of miR-210 was further detected by qRT-PCR and Western blot, respectively. The microvessels density of myocardium was evaluated by CD31 immunostaining.

RESULTS

Compared with the sham group, ejection fraction (EF) and fractional shortening (FS) values were decreased significantly in the AMI group (P<0.01), while the infarction area and the interstitial collagen deposition were increased obviously. As for the AMI+HAR group, EF and FS values were increased significantly (P<0.05 vs. AMI group), and the infarction area was reduced and the interstitial collagen deposition were alleviated significantly. Total of 23 miRNAs in the AMI group expressed differently by at least 1.5 folds compared with those in the sham group; 5 miRNAs in the AMI+HAR group expressed differently by at least 1.5 folds compared with those in the AMI group. Among them, miR-210 was low in the AMI group and high in the AMI+HAR group. The relative mRNA and protein expressions of VEGF were decreased significantly in the AMI group (P<0.05 vs. sham group), and increased significantly in the AMI+HAR group (P<0.01 vs. AMI group). CD31 expression area and optical intensity were decreased significantly in the AMI group (P<0.05 vs. sham group), and increased significantly in the AMI+HAR group (P<0.01 vs. AMI group).

CONCLUSIONS

HAR could reduce the infarction area, alleviate the interstitial fibrosis and improve the cardiac function of AMI rats. Those effects could be related to promoting myocardium angiogenesis of HAR by up-regulating miR-210 and VEGF.

Improved skin flap survival in venous ischemia-reperfusion injury with the use of adipose-derived stem cells

INTRODUCTION

The purpose of this study was to investigate the efficacy of stem cell therapy as an adjuvant treatment for congested skin flap.

METHOD

Sprague-Dawley rats (n = 21) were randomized into three groups. In group I, the flap was sutured without venous ischemia. In group II, the vein was selectively clamped for 4 hours, and complete medium was administered upon clamp removal. In group III, ADSCs were administered upon removing the clamp. On postoperative day 7, the survival areas and the histopathologic findings were assessed. In addition, the expression of heme oxygenase (HO)-1 and nuclear factor (NF)-κB was assessed using immunofluorescent staining and western blot analyses.

RESULTS

Compared with group II, group III showed significantly increased flap survival (31.2% ± 11.9% vs. 51.6% ± 13.6%, P < 0.05). The degree of histological abnormalities was significantly lower in group III than in group II (9.38% ± 1.39 vs. 6.46% ± 2.57, P < 0.05). In addition, in group III, the expression of NF-κB was significantly lower (0.51 ± 0.21 vs. 0.34 ± 0.21, P < 0.05), whereas that of HO-1 was significantly higher (0.25 ± 0.11 vs. 0.43 ± 0.18, P < 0.01). Immunofluorescent staining also showed more HO-1-positive cells in group III than in group II (10.9% ± 1.6% vs. 16.0% ± 1.7%, P < 0.01).

CONCLUSION

Our study demonstrated that treatment with ADSCs significantly increased flap survival in venous ischemia-reperfusion conditions. Further investigation of these protective effects and optimization of the treatment protocol could make cell therapy a viable treatment.

Intra-carotid arterial administration of autologous peripheral blood-derived endothelial progenitor cells improves acute ischemic stroke neurological outcomes in rats

OBJECTIVE

We tested the hypothesis that transfusion of autologous peripheral blood-derived endothelial progenitor cells (PBDEPC) via the internal carotid artery could reduce brain-infarct zone (BIZ) and neurological deficit in rats following acute ischemic stroke (IS) induced by 50-min left middle cerebral artery occlusion.

DESIGN

Adult male Sprague-Dawley rats (n=60) were equally divided into group 1 [sham control (SC)], group 2 [SC-PBDEPC (5.7 × 10(6)/kg)], group 3 (IS), group 4 [IS-low-dose PBDEPC (1.7 × 10(6)/kg)], group 5 [IS-high-dose PBDEPC (5.7×10(6)/kg)]. Groups 2 to 5 received G-CSF (35 μg/kg subcutaneously) for 4 days before drawing blood for PBDEPC culture.

MEASUREMENTS AND MAIN RESULTS

By day 90, BIZ determined by histopathology (area) and brain MRI (volume) were highest in group 3, lowest in groups 1 and 2, higher in group 4 than in group 5 (all p<0.0001), and not significantly different between groups 1 and 2. Sensorimotor functional results exhibited an opposite pattern of BIZ among groups 3 to 5 (p<0.005). Angiogenesis biomarkers (SDF-1α, CXCR4, VEGF, angiopoietin-1) significantly increased progressively from groups 1 and 2 to group 5 (all p<0.0001). Oxidative-stress (NOX-1, NOX-2, oxidized protein), apoptotic (cleaved caspase 3 and PARP, mitochondrial Bax), inflammatory (MMP-9, TNF-α, AQP-4, GFAP, iNOS), and brain-damaged (cytosolic cytochrome-C) biomarkers showed an identical pattern, whereas anti-inflammatory (Bcl-2), mitochondrial preservation (mitochondrial cytochrome-C, PGC-1α), and endothelial function (CD31+, vWF+, eNOS) biomarkers, and vessel density showed an opposite pattern of BIZ among these five groups (all p<0.001).

CONCLUSION

Higher-dose was superior to lower-dose EPC treatment for reducing BIZ and improving neurological functional outcome.

Combined therapy with shock wave and autologous bone marrow-derived mesenchymal stem cells alleviates left ventricular dysfunction and remodeling through inhibiting inflammatory stimuli, oxidative stress & enhancing angiogenesis in a swine myocardial infarction model

BACKGROUND

We hypothesized that combined therapy with shock wave (SW) and autologous bone marrow-derived mesenchymal stem cells (BMDMSCs) is superior to either therapy alone for alleviating left ventricular (LV) dysfunction.

METHODS AND RESULTS

Male mini-pigs (n=30) equally divided into group 1 (sham control), group 2 [acute myocardial infarction (AMI) by left coronary artery ligation], group 3 (AMI-SW), group 4 (AMI-BMDMSC), and group 5 (AMI-SW-BMDMSC) were sacrificed by day 60 and the hearts were collected for studies. Baseline LV injection fraction [LVEF (%)] and LV chamber size did not differ among the five groups (p>0.5). By day 60, LVEF was highest in group 1 and lowest in group 2, significantly higher in group 5 than that in groups 3 and 4, and significantly higher in group 4 than that in group 3 (p<0.001). Cellular and protein levels of VEGF, CXCR4, and SDF-1α were significantly increased progressively from groups 1 to 5 (all p<0.05). Small vessel number and protein expressions of CD31 and eNOS were highest in groups 1 and 5, lowest in group 2, and significantly higher in group 4 than those in group 3 (p<0.001). Protein (MMP-9, TNF-1α and NF-κB) and cellular (CD14+, CD40+) levels of inflammatory biomarkers, protein expressions of oxidative stress (oxidized protein, NOX-1, NOX-2), apoptosis (Bax, caspase-3, PARP), infarct size, and LV dimensions showed a pattern opposite to that of LVEF among all groups (all p<0.001).

CONCLUSIONS

Combined SW-BMDMSC therapy is superior to either therapy alone for improving LVEF, reducing infarct size, and inhibiting LV remodeling.

Prompt bone marrow-derived mesenchymal stem cell therapy enables early porcine heart function recovery from acute myocardial infarction

Impact of early bone marrow-derived mesenchymal stem cell (BMDMSC) implantation on left ventricular (LV) function after AMI was studied.Twelve mini-pigs were equally divided into placebo (AMI through left coronary artery ligation) and cell-treated groups [BMDMSCs (3.0 × 10(7)) implanted into infarct area (IA)] with myocardium harvested by post-AMI day 90. Six healthy animals served as controls.On post-AMI day 90, magnetic resonance imaging showed a lower LV ejection fraction but higher LV dimensions in the placebo group (P < 0.003) that also had increased IAs but reduced wall thickness (P < 0.005). Pro-apoptotic gene expressions (Bax, caspase-3) and apoptotic nucleus number in IAs and peri-IAs were highest in the placebo group (P < 0.001). Inflammatory biomarker expressions (MMP-9, oxidized protein, CD40+ cells) were highest, whereas those of angiogenesis (VEGF, CD31+ cells, SDF-1α, CXCR4) and myocardium-preservation (connexin43, troponin-I, cytochrome-C) were lowest in the placebo group (P < 0.01).BMDMSC implantation preserved LV function and alleviated remodeling at post-AMI day 90.

Direct implantation versus platelet-rich fibrin-embedded adipose-derived mesenchymal stem cells in treating rat acute myocardial infarction

BACKGROUND

This study tested whether adipose-derived mesenchymal stem cells (ADMSC) embedded in platelet-rich fibrin (PRF) scaffold is superior to direct ADMSC implantation in improving left ventricular (LV) performance and reducing LV remodeling in a rat acute myocardial infarction (AMI) model of left anterior descending coronary artery (LAD) ligation.

METHODS

Twenty-eight male adult Sprague Dawley rats equally divided into group 1 [sham control], group 2 (AMI only), group 3 (AMI+direct ADMSC implantation), and group 4 (AMI+PRF-embedded autologous ADMSC) were sacrificed on day 42 after AMI.

RESULTS

LV systolic and diastolic dimensions and volumes, and infarct/fibrotic areas were highest in group 2, lowest in group 1 and significantly higher in group 3 than in group 4, whereas LV performance and LV fractional shortening exhibited a reversed pattern (p<0.005). Protein expressions of inflammation (oxidative stress, IL-1β, MMP-9), apoptosis (mitochondrial Bax, cleaved PARP), fibrosis (Smad3, TGF-β), and pressure-overload biomarkers (BNP, MHC-β) displayed a pattern similar to that of LV dimensions, whereas anti-inflammatory (IL-10), anti-apoptotic (Bcl-2), and anti-fibrotic (Smad1/5, BMP-2) indices showed a pattern similar to that of LV performance among the four groups (all p<0.05). Angiogenesis biomarkers at protein (CXCR4, SDF-1α, VEGF), cellular (CD31+, CXCR4+, SDF-1α+), and immunohistochemical (small vessels) levels, and cardiac stem cell markers (C-kit+, Sca-1+) in infarct myocardium were highest in group 4, lowest in group 1, and significantly higher in group 3 than in group 2 (all p<0.005).

CONCLUSION

PRF-embedded ADMSC is superior to direct ADMSC implantation in preserving LV function and attenuating LV remodeling.

Chemokine contribution in stem cell engraftment into the infarcted myocardium

Modern life styles have made cardiovascular disease the leading cause of morbidity and mortality worldwide. Although current treatments substantially ameliorate patients’ prognosis after MI, they cannot restore the affected tissue or entirely re-establish organ function. Therefore, the main goal of modern cardiology should be to design strategies to reduce myocardial necrosis and optimize cardiac repair following MI. Cell-based therapy was considered a novel and potentially new strategy in regenerative medicine; however, its clinical implementation has not yielded the expected results. Chemokines seem to increase the efficiency of cell-therapy and may represent a reliable method to be exploited in the future. This review surveys current knowledge of cell therapy and highlights key insights into the role of chemokines in stem cell engraftment in infarcted myocardium and their possible clinical implications.

Protection of mesenchymal stem cells on acute kidney injury

The aim of the present study was to determine the protection of allogeneic bone marrow mesenchymal stem cells (BMSCs) on an ischaemia/reperfusion (I/R)‑induced acute kidney injury (AKI) rat model and to investigate the underlying mechanisms. The BMSCs were isolated and cultured from adult Sprague‑Dawley (SD) rats and the I/R‑induced AKI model was established by bilateral clamping of renal pedicles for 60 min. Following successfully establishing the AKI model, 1x106 BMSCs were administered by intrarenal injection. All animals were randomly divided into four groups (n=10 in each): 1 (sham control), 2 (I/R), 3 (I/R+culture medium) and 4 (I/R+BMSCs). Serum levels of creatinine (Cr) and blood urea nitrogen (BUN) were measured in all four groups at 24 and 72 h. Three days post‑surgery, the level of inflammatory factors, including interleukin‑6 (IL‑6), tumour necrosis factor‑α (TNF‑α) and vascular endothelial growth factor (VEGF) in the kidney was analysed by quantitative polymerase chain reaction. Three days following surgery, mRNA expression levels of IL‑6 and TNF‑α were significantly lower, however, the expression level of VEGF was significantly higher in group 4 compared with groups 2 and 3 (P<0.05). By contrast, the immunofluorescence results showed that the injected BMSCs differentiated into vascular endothelial cells. In conclusion, the present study identified that intrarenal administration of BMSCs improved I/R‑induced AKI through the anti‑inflammatory effect and a paracrine mechanism and therefore, may be hypothesised for the use in clinical trials.

Innate immune response after acute myocardial infarction and pharmacomodulatory action of tacrolimus in reducing infarct size and preserving myocardial integrity

Background

This study investigated the association between innate immune reaction and myocardial damage after acute myocardial infarction (AMI) and anti-inflammatory role of tacrolimus in reducing infarct size. Male mini-pigs (n=18) were equally categorized into sham control (SC), untreated AMI (by ligation of left anterior descending coronary artery), and AMI-Tacrolimus (AMI-Tac) (0.5 mg intra-coronary injection 30 minutes post-AMI). Cardiac magnetic resonance imaging (MRI) was performed at post-AMI days 2, 5 and 21 before sacrificing the animals.

Results

By post-AMI day 21, left ventricular ejection fraction (LVEF) was lowest in untreated AMI animals, significantly higher in SC than in AMI-Tac group (all p<0.003). Infarct areas at basal, middle, and apical levels, numbers of CD14+ and iNOS+ cells in infarct area (IA) and peri-IA, and protein expression of CD14, CD68, and Ly6g from circulating inflammatory cells showed an opposite pattern compared with that of LVEF in all groups (all p<0.005). Protein expressions of MCP-1, MIP-1, TNF-α, NF-κB, iNOS, and IL-12 in IA and peri-IA exhibited an identical pattern compared to that of CD14, CD68, and Ly6g from circulating inflammatory cells (all p<0.01). Expressions of myocardial damage biomarkers in IA and peri-IA [γ-H2AX, β-myosin heavy chain (MHC), Smad3, TGF-β] were highest in AMI and higher in AMI-Tac than in SC, whereas expressions of myocardial integrity biomarkers (connexin43, mitochondrial cytochrome-C, α-MHC, BMP-2, Smad1/5) were opposite to those of damage biomarkers (all p<0.001).

Conclusion

Innate immune responses were markedly augmented and LVEF was significantly reduced after AMI but were remarkably improved after tacrolimus treatment.

Cyclosporine-assisted adipose-derived mesenchymal stem cell therapy to mitigate acute kidney ischemia-reperfusion injury

Introduction

This study tested the hypothesis that cyclosporine (CsA)-supported syngeneic adipose-derived mesenchymal stem cell (ADMSC) therapy offered superior attenuation of acute ischemia–reperfusion (IR) kidney injury to either therapy alone.

Methods

Adult Sprague–Dawley rats (n = 40) were equally divided into group 1 (sham controls), group 2 (IR injury), group 3 (IR + CsA (20 mg/kg at 1 and 24 hours after procedure)), group 4 (syngeneic ADMSC (1.2×10⁶) at 1, 6 and 24 hours after procedure), and group 5 (IR + CsA-ADMSC).

Results

By 72 hours after the IR procedure, the creatinine level and the ratio of urine protein to creatinine were highest in group 2 and lowest in group 1, and significantly higher in groups 3 and 4 than in group 5 (all P <0.05 for inter-group comparisons), but showed no differences between groups 3 and 4 (P >0.05). The inflammatory biomarkers at mRNA (matrix metalloproteinase-9, RANTES, TNF-α), protein (TNF-α, NF-κB, intercellular adhesion molecule-1, platelet-derived growth factor), and cellular (CD68⁺) levels of IR kidney showed a similar pattern compared with that of creatinine in all groups (all P <0.05 for inter-group comparisons). The protein expressions of oxidative stress (oxidized protein), reactive oxygen species (NADPH oxidases NOX-1, NOX-2), apoptosis (Bcl-2–associated X protein, caspase-3 and poly(ADP-ribose) polymerase) and DNA damage (phosphorylated H2A histone family member X-positive, proliferating cell nuclear antigen-positive cells) markers exhibited a pattern similar to that of inflammatory mediators amongst all groups (all P <0.05 for inter-group comparisons). Expressions of antioxidant biomarkers at cellular (glutathione peroxidase, glutathione reductase, heme oxygenase-1 (HO-1)) and protein (NADPH dehydrogenase (quinone)-1, HO-1, endothelial nitric oxide synthase) levels, and endothelial progenitor cell markers (C-X-C chemokine receptor type 4-positive, stromal cell-derived factor-1α-positive) were lowest in groups 1 and 2, higher in groups 3 and 4, and highest in group 5 (all P <0.05 for inter-group comparisons).

Conclusion

Combination therapy using CsA plus ADMSCs offers improved protection against acute IR kidney injury.

The proarrhythmic risk of cell therapy for cardiovascular diseases

Stem cell therapy is an emerging therapeutic approach for the treatment of cardiovascular diseases. Experimental studies have demonstrated that different types of stem cells, including bone marrow-derived cells, mesenchymal stem cells, skeletal myoblasts, and cardiac progenitor cells and embryonic stem cells, can improve cardiac function after myocardial injuries. Nevertheless, the potential proarrhythmic risk after stem cell transplantation remains a major concern. Several mechanisms, including the immaturity of electrical phenotypes of the transplanted cardiomyocytes, poor cell-cell coupling and cardiac nerve sprouting, may contribute to arrhythmogenic risk after stem cell transplantation. This review summarizes the potential theoretical arrhythmogenic mechanisms associated with different types of stem cells for the treatment of cardiovascular diseases. Nevertheless, current experimental and clinical data on the proarrhythmic risk for different types of stem cell transplantation are limited, and await further experimental and clinical investigation.

Intra-coronary administration of tacrolimus markedly attenuates infarct size and preserves heart function in porcine myocardial infarction

Background

We test the hypothesis that intra-coronary tacrolimus administration can limit infarct size and preserve left ventricular ejection fraction (LVEF) after acute myocardial infarction (AMI) through ligating left anterior descending coronary artery (LAD) in mini-pigs.

Methods

Twelve male mini-pigs were randomized into AMI-saline (MI-only) group and AMI-tacrolimus (MI-Tac) group that received intra-coronary saline (3.0 mL) and tacrolimus (0.5 mg in 2.5 mL saline) injection, respectively, beyond site of ligation 30 minutes after LAD occlusion.

Results

Larger infarct area was noted in MI-only group (p < 0.001). Inflammatory biomarkers at protein [oxidative stress, tumor necrotic factor-α, nuclear factor-κB], gene (matrix metalloproteinase-9, plasminogen activator inhibitor-1), and cellular (CD40+, CD68+ inflammatory cells) levels were remarkably higher in MI-only animals (p < 0.01). Conversely, anti-inflammatory biomarkers at gene level (Interleukin-10), gene and protein level (endothelial nitric oxide synthase), and anti-oxidant biomarkers at both gene and protein levels [heme oxygenase 1, NAD(P)H:quinone oxidoreductase] were lower in MI-only group (p < 0.01). Number of apoptotic nuclei and apoptotic biomarkers expressions at gene and protein levels (Bax, caspase 3) were notably higher, whereas anti-apoptotic biomarkers at gene and protein levels (Bcl-2), LVEF, and fractional shortening were markedly lower in MI-only group (p < 0.001).

Conclusion

Intra-coronary administration of tacrolimus significantly attenuated infarct size and preserved LV function.

Systemic administration of autologous adipose-derived mesenchymal stem cells alleviates hepatic ischemia-reperfusion injury in rats

OBJECTIVES

Mesenchymal stem cells have previously been shown to offer significant therapeutic benefit in ischemic organ injuries. This study aimed at investigating the therapeutic role of adipose tissue-derived mesenchymal stem cells in hepatic ischemia-reperfusion injury and the underlying mechanisms.

DESIGN

Adult male Fisher rats (n = 30) were equally divided into three groups (group 1: Sham-operated normal controls; group 2: Ischemia-reperfusion injury with intravenous fresh culture medium; group 3: Ischemia-reperfusion injury with intravenous adipose tissue-derived mesenchymal stem cells). Ischemia-reperfusion injury was induced by occluding the vascular supplies of left lobe liver for 60 minutes followed by reperfusion for 72 hrs. Adipose tissue-derived mesenchymal stem cells (1.2 × 106) were administered through tail vein immediately after reperfusion and at 6 hrs and 24 hrs after reperfusion in group 3. All animals were sacrificed 72 hrs after reperfusion.

SETTING

Animal laboratory at a medical institute.

MEASUREMENTS AND MAIN RESULTS

Histologic features, plasma aspartate aminotransferase, hepatic cytokine profile, oxidative stress, and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling were analyzed. Seventy-two hrs after reperfusion, plasma aspartate aminotransferase, hepatic oxidative stress, messenger RNA expressions of tumor necrosis factor-a, transforming growth factor-b, interleukin-1b, interleukin-6, endothelin-1, matrix metalloproteinase-9, plasminogen activator inhibitor-1, Bax and caspase-3, protein expression of intercellular adhesion molecule as well as the number of apoptotic nuclei were significantly increased in group 2 compared with group 3, whereas messenger RNA expressions of endothelial nitric oxide synthase, Bcl-2, interleukin-10, protein expressions of reduced nicotinamide-adenine dinucleotide phosphate:quinone oxidoreductase 1, and heme oxygenase-1 were lower in group 2 than group 3.

CONCLUSIONS

The results showed that systemic adipose tissue-derived mesenchymal stem cell administration significantly preserved hepatocyte integrity and suppressed inflammatory responses, oxidative stress, and apoptosis in a rodent model of hepatic ischemia-reperfusion injury.

Effects of autologous bone marrow mononuclear cells implantation in canine model of pulmonary hypertension

BACKGROUND

We investigated the safety and feasibility of intratracheal administration of autologous bone marrow-derived mononuclear cells (ABM-MNCs) and observed the effects in a canine model of pulmonary hypertension (PH).

METHODS AND RESULTS

The PH model was induced by intravenous injection of 3mg/kg dehydromonocrotaline (DMCT) via the right atrium. Two weeks after DMCT administration, the animals received 4 different treatments (n=10 in each group): (I) negative control group; (II): ABM-MNCs group; (III) PH group; (IV) PH+ABM-MNCs group. Six weeks after injection of cells (10⁷), the hemodynamic data were significantly improved in group IV compared with group III (P<0.05). The ratio of right ventricular weight to left ventricular plus septal weight was significantly decreased in group IV compared with group III (P<0.05). The mRNA levels of vascular endothelial growth factor, preproendothelin-1, interleukin-6 and tumor necrosis factor-α were significantly improved in group IV compared with group III (P<0.05). The immunofluorescence result showed that 6 weeks after administration ABM-MNCs could differentiate into pulmonary vascular endothelial cells.

CONCLUSIONS

Six weeks after intratracheal administration, ABM-MNCs significantly improved the impairment caused by DMCT in a canine model of PH (ie, decreased pulmonary arteriolar narrowing, alveolar septum thickening and right ventricular hypertrophy, enhanced angiogenesis) and this provides a firm foundation for a clinical trial.

Implantation of bone marrow-derived buffy coat can supplement bone marrow stimulation for articular cartilage repair

OBJECTIVE

Bone marrow stimulation (BMS) has been regarded as a first line procedure for repair of articular cartilage. However, repaired cartilage from BMS is known to be unlike that of hyaline cartilage and its inner endurance is not guaranteed. The reason presumably came from a shortage of cartilage-forming cells in blood clots derived by BMS. In order to increase repairable cellularity, the feasibility of autologous bone marrow-derived buffy coat transplantation in repair of large full-thickness cartilage defects was investigated in this study.

METHODS

Rabbits were divided into four groups: the defect remained untreated as a negative control; performance of BMS only (BMS group); BMS followed by supplementation of autologous bone marrow buffy coat (Buffy coat group); transplantation of autologous osteochondral transplantation (AOTS) as a positive control.

RESULTS

Repair of cartilage defects in the Buffy coat group in a rabbit model was more effective than BMS alone and similar to AOTS. Gross findings, histological analysis, histological scoring, immunohistochemistry, and chemical assay demonstrated that supplementation of autologous bone marrow buffy coat after BMS arthroplasty effectively repaired cartilage defects in a rabbit model, and was more effective than BMS arthroplasty alone.

CONCLUSION

Supplementation of autologous bone marrow-derived buffy coat in cases of BMS could be a useful clinical protocol for cartilage repair.

Extracorporeal shock wave therapy reverses ischemia-related left ventricular dysfunction and remodeling: molecular-cellular and functional assessment

An optimal treatment for patients with diffuse obstructive arterial disease unsuitable for catheter-based or surgical intervention is still pending. This study tested the hypothesis that extracorporeal shock wave (ECSW) therapy may be a therapeutic alternative under such clinical situation. Myocardial ischemia was induced in male mini-pigs through applying an ameroid constrictor over mid-left anterior descending artery (LAD). Twelve mini-pigs were equally randomized into group 1 (Constrictor over LAD only) and group 2 (Constrictor over LAD plus ECSW [800 impulses at 0.09 mJ/mm²] once 3 months after the procedure). Results showed that the parameters measured by echocardiography did not differ between two groups on days 0 and 90. However, echocardiography and left ventricular (LV) angiography showed higher LV ejection fraction and lower LV end-systolic dimension and volume in group 2 on day 180 (p<0.035). Besides, mRNA and protein expressions of CXCR4 and SDF-1α were increased in group 2 (p<0.04). Immunofluorescence staining also showed higher number of vWF-, CD31-, SDF-1α-, and CXCR4-positive cells in group 2 (all p<0.04). Moreover, immunohistochemical staining showed notably higher vessel density but lower mean fibrosis area, number of CD40-positive cells and apoptotic nuclei in group 2 (all p<0.045). Mitochondrial protein expression of oxidative stress was lower, whereas cytochrome-C was higher in group 2 (all p<0.03). Furthermore, mRNA expressions of MMP-9, Bax and caspase-3 were lower, whereas Bcl-2, eNOS, VEGF and PGC-1α were higher in group 2 (all p<0.01). In conclusion, ECSW therapy effectively reversed ischemia-elicited LV dysfunction and remodeling through enhancing angiogenesis and attenuating inflammation and oxidative stress.

Autologous transplantation of adipose-derived mesenchymal stem cells markedly reduced acute ischemia-reperfusion lung injury in a rodent model

Background

This study tested the hypothesis that autologous transplantation of adipose-derived mesenchymal stem cells (ADMSCs) can effectively attenuate acute pulmonary ischemia-reperfusion (IR) injury.

Methods

Adult male Sprague-Dawley (SD) rats (n = 24) were equally randomized into group 1 (sham control), group 2 (IR plus culture medium only), and group 3 (IR plus intravenous transplantation of 1.5 × 10⁶ autologous ADMSCs at 1h, 6h, and 24h following IR injury). The duration of ischemia was 30 minutes, followed by 72 hours of reperfusion prior to sacrificing the animals. Blood samples were collected and lungs were harvested for analysis.

Results

Blood gas analysis showed that oxygen saturation (%) was remarkably lower, whereas right ventricular systolic pressure was notably higher in group 2 than in group 3 (all p < 0.03). Histological scoring of lung parenchymal damage was notably higher in group 2 than in group 3 (all p < 0.001). Real time-PCR demonstrated remarkably higher expressions of oxidative stress, as well as inflammatory and apoptotic biomarkers in group 2 compared with group 3 (all p < 0.005). Western blot showed that vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-1, oxidative stress, tumor necrosis factor-α and nuclear factor-κB were remarkably higher, whereas NAD(P)H quinone oxidoreductase 1 and heme oxygenase-1 activities were lower in group 2 compared to those in group 3 (all p < 0.004). Immunofluorescent staining demonstrated notably higher number of CD68+ cells, but significantly fewer CD31+ and vWF+ cells in group 2 than in group 3.

Conclusion

ADMSC therapy minimized lung damage after IR injury in a rodent model through suppressing oxidative stress and inflammatory reaction.

Enhanced protection against pulmonary hypertension with sildenafil and endothelial progenitor cell in rats

BACKGROUND

Sildenafil and bone marrow-derived endothelial progenitor cells (BMDEPCs) have been shown to ameliorate monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH) in the rat. We test whether combined sildenafil and BMDEPC treatment exerts additional protection against MCT-induced PAH in rats.

METHODS

Male Sprague-Dawley rats were randomized to receive saline injection only (group 1), MCT (70 mg/kg) only (group 2), MCT plus autologous BMDEPC (2.0×10(6) cells) transplantation (group 3), MCT with sildenafil (30 mg/kg/day) (group 4), and MCT with combined BMDEPCs-sildenafil (30 mg/kg/day) (group 5). Intravenous BMDEPC and oral sildenafil were given on day 3 after MCT administration. Hemodynamics were analyzed using Labchart software, whereas cellular and molecular parameters were measured using flow cytometry, real-time PCR, TUNEL assay, Western blot, and immunohistochemical staining.

RESULTS

By day 35 following MCT treatment, lower expression of connexin43, protein kinase C-ε, Bcl-2, and endothelial nitric oxide synthase and higher expression of tumor necrosis factor-α and caspase 3 were found in right ventricle (RV) and lung in group 2 compared with other groups (all p<0.05). The number of alveolar sacs and lung arterioles were also lower in group 2 than in other groups (all p<0.05). Furthermore, RV systolic pressure (RVSP), RV weight, and RV-to-final body weight ratio were substantially increased in group 2 than in other groups, and notably higher in groups 3 and 4 than in groups 1 and 5 (all p<0.0001).

CONCLUSIONS

Combined therapy with autologous BMDEPC and sildenafil is superior to either BMDPEC or sildenafil alone for preventing MCT-induced PAH.

Adipose-derived mesenchymal stem cell protects kidneys against ischemia-reperfusion injury through suppressing oxidative stress and inflammatory reaction

Background

Reactive oxygen species are important mediators exerting toxic effects on various organs during ischemia-reperfusion (IR) injury. We hypothesized that adipose-derived mesenchymal stem cells (ADMSCs) protect the kidney against oxidative stress and inflammatory stimuli in rat during renal IR injury.

Methods

Adult male Sprague-Dawley (SD) rats (n = 24) were equally randomized into group 1 (sham control), group 2 (IR plus culture medium only), and group 3 (IR plus immediate intra-renal administration of 1.0 × 10⁶ autologous ADMSCs, followed by intravenous ADMSCs at 6 h and 24 h after IR). The duration of ischemia was 1 h, followed by 72 hours of reperfusion before the animals were sacrificed.

Results

Serum creatinine and blood urea nitrogen levels and the degree of histological abnormalities were markedly lower in group 3 than in group 2 (all p < 0.03). The mRNA expressions of inflammatory, oxidative stress, and apoptotic biomarkers were lower, whereas the anti-inflammatory, anti-oxidative, and anti-apoptotic biomarkers were higher in group 3 than in group 2 (all p < 0.03). Immunofluorescent staining showed a higher number of CD31+, von Willebrand Factor+, and heme oxygenase (HO)-1+ cells in group 3 than in group 2 (all p < 0.05). Western blot showed notably higher NAD(P)H quinone oxidoreductase 1 and HO-1 activities, two indicators of anti-oxidative capacity, in group 3 than those in group 2 (all p < 0.04). Immunohistochemical staining showed higher glutathione peroxidase and glutathione reductase activities in group 3 than in group 2 (all p < 0.02)

Conclusion

ADMSC therapy minimized kidney damage after IR injury through suppressing oxidative stress and inflammatory response.

Improvement of cardiac function by intracoronary freshly isolated bone marrow cells transplantation in patients with acute myocardial infarction

BACKGROUND

We analyzed in the present study the influence of intracoronary autologous freshly isolated bone marrow cells transplantation (BMCs-Tx) on cardiac function in patients with acute myocardial infarction (AMI).

METHODS AND RESULTS

The 32 patients with AMI were enrolled in this prospective nonrandomized study to either freshly isolated BMC-Tx or to a control group without cell therapy. Global left ventricular ejection fraction (LVEF) and the size of infarct area were determined by left ventriculography. We observed in patients with autologous freshly isolated BMCs-Tx at 6 months follow up a significant reduction of infarct size as compared to control group. Moreover, we found a significant increase of LVEF as well as infarct wall movement velocity at 6 months follow up in cell therapy group as compared to control group. In the control group there was no significant difference of LVEF, infarct size and infarct wall movement velocity between baseline and 6 months after AMI.

CONCLUSIONS

These results demonstrate for the first time that intracoronary transplantation of autologous freshly isolated BMCs by use of a point of care system is safe, and may lead to improvement of cardiac function in patients with AMI.

Myocardium-derived conditioned medium improves left ventricular function in rodent acute myocardial infarction

BACKGROUND

We investigated whether myocardium-derived conditioned medium (MDCM) is effective in preserving left ventricular (LV) function in a rat acute myocardial infarction (AMI) model.

METHODS

Adult male Sprague-Dawley (SD) rats (n = 36) randomized to receive either left coronary artery ligation (AMI induction) or thoracotomy only (sham procedure) were grouped as follows (n = 6 per group): Group I, II, and III were sham-controls treated by fresh medium, normal rat MDCM, and infarct-related MDCM, respectively. Group IV, V, and VI were AMI rats treated by fresh medium, normal MDCM, and infarct-related MDCM, respectively. Either 75 μL MDCM or fresh medium was administered into infarct myocardium, followed by intravenous injection (3 mL) at postoperative 1, 12, and 24 h.

RESULTS

In vitro studies showed higher phosphorylated MMP-2 and MMP-9, but lower α-smooth muscle actin and collagen expressions in neonatal cardiac fibroblasts treated with MDCM compared with those in the cardiac fibroblasts treated with fresh medium (all p < 0.05). Sirius-red staining showed larger collagen deposition area in LV myocardium in Group IV than in other groups (all p < 0.05). Stromal cell-derived factor-1α and CXCR4 protein expressions were higher in Group VI than in other groups (all p < 0.05). The number of von Willebrand factor- and BrdU-positive cells and small vessels in LV myocardium as well as 90-day LV ejection fraction were higher, whereas oxidative stress was lower in Group VI than in Group IV and Group V (all p < 0.05).

CONCLUSION

MDCM therapy reduced cardiac fibrosis and oxidative stress, enhanced angiogenesis, and preserved 90-day LV function in a rat AMI model.

Shock wave-pretreated bone marrow cells further improve left ventricular function after myocardial infarction in rabbits

BACKGROUND

We tested whether shock wave (SW) offers additional benefits in improving left ventricular (LV) function after acute myocardial infarction (AMI) in rabbits receiving SW-treated autologous bone marrow-derived mononuclear cells (BMDMNCs) transplantation.

METHODS AND RESULTS

Saline (750 microL; group 2), BMDMNCs (1.0 x 10(7); group 3), or preimplant SW-treated BMDMNCs (group 4) were implanted into the infarct area of male rabbits 15 minutes after left coronary artery ligation, whereas eight rabbits without AMI served as controls (group 1; n = 8 per group). The results showed that in infarct area of LV, protein expressions of Cx43 and cytochrome C in mitochondria and endothelial nitric oxide synthase mRNA expression were lower in group 2 than in other groups, and decreased in group 3 as compared with groups 1 and 4 (all p values < 0.01). Conversely, mRNA expressions of endothelin-1 and matrix metalloproteinase-9, mitochondrial oxidative stress, and total fibrotic area were higher in group 2 than in other groups (all p values < 0.05). Furthermore, 6-month LV function by 2-D echo/angiogram showed significant impairment in group 2 than in other groups and in group 3 than in groups 1 and 4 (all p values < 0.005).

CONCLUSIONS

Application of SW-treated autologous BMDMNCs is superior to BMDMNCs alone for preserving LV function after AMI.

Early combined treatment with sildenafil and adipose-derived mesenchymal stem cells preserves heart function in rat dilated cardiomyopathy

Background

We investigated whether early combined autologous adipose-derived mesenchymal stem cell (ADMSC) and sildenafil therapy offers an additive benefit in preserving heart function in rat dilated cardiomyopathy (DCM).

Methods

Adult Lewis rats (n = 8 per group) were divided into group 1 (normal control), group 2 (saline-treated DCM rats), group 3 [2.0 × 10⁶ ADMSC implanted into left ventricular (LV) myocardium of DCM rats], group 4 (DCM rats with sildenafil 30 mg/kg/day, orally), and group 5 (DCM rats with combined ADMSC-sildenafil). Treatment was started 1 week after DCM induction and the rats were sacrificed on day 90.

Results

The results showed that mitochondrial protein expressions of connexin43 and cytochrome-C were lowest in group 2, and lower in groups 3 and 4 than in group 5 (p < 0.002). Conversely, oxidative index was highest in group 2, and also higher in groups 3 and 4 than in group 5 (p < 0.0003). The mRNA expressions of interleukin (IL)-10, Gro/IL-8, endothelial nitric oxide synthase, and Bcl-2 were lowest in group 2, and lower in groups 3 and 4 compared with group 5 (p < 0.0001). The mRNA expressions of matrix metalloproteinase-9, Bax, caspase 3, and stromal-cell derived factor-1α were highest in group 2, and higher in groups 3 and 4 than in group 5 (p < 0.0004). Apoptosis and fibrosis in LV myocardium were most prominent in group 2 and higher in groups 3 and 4 than in group 5, whereas angiogenesis and LV ejection fraction were lowest in group 2 and lower in groups 3 and 4 than in group 5 (p < 0.003).

Conclusion

Early combined ADMSC/sildenafil is superior to either treatment alone in preserving LV function.

Adipose-derived mesenchymal stem cells markedly attenuate brain infarct size and improve neurological function in rats

Background

The therapeutic effect of adipose-derived mesenchymal stem cells (ADMSCs) on brain infarction area (BIA) and neurological status in a rat model of acute ischemic stroke (IS) was investigated.

Methods

Adult male Sprague-Dawley (SD) rats (n = 30) were divided into IS plus intra-venous 1 mL saline (at 0, 12 and 24 h after IS induction) (control group) and IS plus intra-venous ADMSCs (2.0 × 10⁶) (treated interval as controls) (treatment group) after occlusion of distal left internal carotid artery. The rats were sacrificed and brain tissues were harvested on day 21 after the procedure.

Results

The results showed that BIA was larger in control group than in treatment group (p < 0.001). The sensorimotor functional test (Corner test) identified a higher frequency of turning movement to left in control group than in treatment group (p < 0.05). mRNA expressions of Bax, caspase 3, interleukin (IL)-18, toll-like receptor-4 and plasminogen activator inhibitor-1 were higher, whereas Bcl-2 and IL-8/Gro were lower in control group than in treatment group (all p < 0.05). Western blot demonstrated a lower CXCR4 and stromal-cell derived factor-1 (SDF-1) in control group than in treatment group (all p < 0.01). Immunohistofluorescent staining showed lower expressions of CXCR4, SDF-1, von Willebran factor and doublecortin, whereas the number of apoptotic nuclei on TUNEL assay was higher in control group than in treatment group (all p < 0.001). Immunohistochemical staining showed that cellular proliferation and number of small vessels were lower but glial fibrillary acid protein was higher in control group than in treatment group (all p < 0.01).

Conclusions

ADMSC therapy significantly limited BIA and improved sensorimotor dysfunction after acute IS.

Low connexin channel-dependent intercellular communication in human adult hematopoietic progenitor/stem cells: probing mechanisms of autologous stem cell therapy

Human bone marrow is a clinical source of autologous progenitor stem cells showing promise for cardiac repair following ischemic insult. Functional improvements following delivery of adult bone marrow CD34⁺ cells into heart tissue may require metabolic/electrical communication between participating cells. Since connexin43 (Cx43) channels are implicated in cardiogenesis and provide intercellular connectivity in the heart, the authors analyzed the expression of 20 connexins (Cx) in CD34⁺ cells and in monocytes and granulocytes in bone marrow and spinal cord. Reverse transcriptase-polymerase chain reaction (RT-PCR) detected only low expression of Cx43 and Cx37. Very low level dye coupling was detected by flow cytometry between CD34⁺ cells and other Cx43 expressing cells, including HL-1 cardiac cells, and was not inhibited by specific gap junction inhibitors. The results indicate that CD34⁺ cells are unlikely to communicate via gap junctions and the authors conclude that use of CD34⁺ cells to repair damaged hearts is unlikely to involve gap junctions. The results concur with the hypothesis that bone marrow cells elicit improved cardiac function through release of undefined paracrine mediators.

Tongue muscle-derived stem cells express connexin 43 and improve cardiac remodeling and survival after myocardial infarction in mice

BACKGROUND

Cell transplantation therapy for heart failure is hindered by poor differentiation into cardiomyocytes and arrhythmias caused by the poor expression of connexin 43 (Cx43). A new stem cell source for cardiac regeneration is needed.

METHODS AND RESULTS

Tongue muscle-derived Sca-1(+) cells (TDSCs) were isolated from normal and green fluorescence protein (GFP)-transgenic mouse tongues using surface antigen Sca-1. Cardiomyogenic differentiation was confirmed by measuring the calcium transient and the expression of cardiac-specific genes. The formation of gap junctions was confirmed by the expression of Cx43 and the dye transfer method. The contraction of regenerated cells was demonstrated by the calcium transients. GFP mouse-derived TDSCs were transplanted into hearts in a model of acute myocardial infarction. Three months after transplantation, LV remodeling was attenuated and the survival rate was improved compared with the control group.

CONCLUSIONS

TDSCs form gap junctions and improve cardiac function and long-term survival after myocardial infarction.

Bone marrow cells reduce fibrogenesis and enhance regeneration in fibrotic rat liver

BACKGROUND

This study aimed at investigating the cellular and molecular impacts of bone marrow-derived mononuclear cells (BMCs) on regeneration of fibrotic liver in rats.

MATERIALS AND METHODS

Thirty male adult Fisher rats were randomized into three groups: group 1 (normal controls, n = 10); group 2 (carbon tetrachloride-induced liver fibrosis, n = 10), and group 3 (liver fibrosis with portal venous infusion of autologous BMCs, 1 × 10(6), n = 10). After 7-d culturing, BMCs were characterized by flow cytometry. Groups 2 and 3 received BMC aspiration through bilateral femurs 5 d before hepatectomy. All animals received 70% hepatectomy, whereas only group 3 received a bolus of intra-portal BMC infusion 48 h after hepatectomy. Liver-to-body weight ratio, degree of fibrosis (Masson trichrome staining), oxidative stress, peroxisome proliferator activated receptor-γ coactivator-1α (PGC-1α), collagen I, tumor necrosis factor-α (TNF-α), and transforming growth factor- β (TGF-β) expressions were analyzed 14 d after hepatectomy. Immunohistochemical staining for albumin, α-smooth muscle actin, and CD31 was performed for tracing cellular differentiation.

RESULTS

Cellular phenotypes typical of hepatocyte, hepatic stellate cell (HSC), and endothelial cell were identified in the engrafted BMCs. Liver-to-body weight ratio was enhanced with PGC-1α significantly preserved, whereas oxidative index, collagen I, α-SMA, TNF-α, and TGF-β expressions were all decreased in group 3 compared with group 2 (all P < 0.05).

CONCLUSIONS

This study demonstrated a positive impact of intra-portal BMC infusion in enhancing regeneration and reducing fibrosis of the regenerating fibrotic liver in rats through suppressing HSC activation and inflammatory cytokine expressions, preserving mitochondrial function and reducing oxidative stress.

Mechanisms of remodelling: a question of life (stem cell production) and death (myocyte apoptosis)

Remodeling myocytes show a typical switch between the embryonic and classical features of apoptosis and/or hypertrophy representing a signal of death (ie, apoptosis) and a signal of life (ie, hypertrophy). The adult myocyte, however, is a terminal cell; usually it is unable to reproduce and death is not genetically programmed (apoptosis), but occurs by necrosis. The reinstatement of apoptosis and development of hypertrophy during remodeling could be part of the switch forward to the embryonic phenotype with reinstatement of the early embryonic genetic program. Hypertrophy and apoptosis are "sons" of the same "mother": the local, tissue neuroendocrine-neurohumoral response to a mechanical stretch of the myocytes consequent to the geometric changes imposed on the viable myocytes by the necrotic ones. As expected, the life and death cycle is very closely regulated by several autocrine systems, one of which is linked to the interleukin-6 family via a regulatory protein named GP-130. Activation of the GP-130 slows down the death signals, thus favoring hypertrophy and reducing fibrosis.

Antioxidant, EUK-8, prevents murine dilated cardiomyopathy

BACKGROUND

Mice lacking manganese-superoxide dismutase (Mn-SOD) activity exhibit the typical pathology of dilated cardiomyopathy (DCM). In the present study, presymptomatic and symptomatic mutant mice were treated with the SOD/catalase mimetic, EUK-8.

METHODS AND RESULTS

Presymptomatic heart/muscle-specific Mn-SOD-deficient mice (H/M-Sod2(-/-)) were treated with EUK-8 (30 mg x kg(-1) . day(-1)) for 4 weeks, and then cardiac function and the reactive oxygen species (ROS) production in their heart mitochondria were assessed. EUK-8 treatment suppressed the progression of cardiac dysfunction and diminished ROS production and oxidative damage. Furthermore, EUK-8 treatment effectively reversed the cardiac dilatation and dysfunction observed in symptomatic H/M-Sod2(-/-) mice. Interestingly, EUK-8 treatment repaired a molecular defect in connexin43.

CONCLUSIONS

EUK-8 treatment can prevent and cure murine DCM, so SOD/catalase mimetic treatment is proposed as a potential therapy for DCM.