Intra-coronary administration of cyclosporine limits infarct size, attenuates remodeling and preserves left ventricular function in porcine acute anterior infarction

Synergic effect of combined cyclosporin and melatonin protects the brain against acute ischemic reperfusion injury

BACKGROUND

This study tested whether combined cyclosporin-A (CsA) and melatonin (Mel) was superior to either one on protecting the brain against ischemia (occluded left-middle-cerebral-artery for 90-min)-reperfusion (for 14 days) injury.

METHODS AND RESULTS

Neuro-2a cells (N2a) were categorized into groups 1 (N2a), 2 (N2a-IR), 3 (N2a-IR-Mel), 4 (N2a-IR-CsA) and 5 (N2a-IR-CsA-Mel). in vitro results showed the protein expressions of cytosolic-cytochrome-C/mitochondrial-Bax/cleaved-capase-3/NOX-1/NOX-2 and flow-cytometric results of ROS (DCFDA/Mito-SOX) were highest in group 2, lowest in group 1, significantly lower in group 5 than in groups 3/4, but they showed no difference in groups 3/4 (all p < 0.001). Male-adult-SD rats (50) were equally categorized into groups 1 (sham-operated-control), 2 (IR), 3 (IR-CsA/20.0 mg/kg at 0.5/24/48 h intraperitoneally after IR), 4 (IR-Mel/50.0 mg/kg intraperitoneally at 30 min and 30 mg/kg at 6/24/48 h after IR) and 5 (IR-CsA-Mel). The brain-infarct-area (BIA) (at day-3 by TTC-stain) was lowest in group 1, highest in group 2, significantly lower in group 5 than groups 3/4, but it showed no difference between groups 3/4 whereas the brain-infarct-volume (at day 14 by MRI) was similar as BIA except for significantly lower in group 4 than in group 3 (all p < 0.0001). By day 14, microscopic finding showed the numbers of glial+/GFAP+/AQP + cells expressed an identical trend whereas the number of NeuN + cells exhibited an opposite pattern of BIA among the groups (all p < 0.0001). The protein expressions of oxidative-stress (NOX-1/NOX-2/p22phox/oxidized-protein), inflammatory (TNF-α/p-NF-κB/MMP-9), apoptotic (mitochondrial-Bax/caspase-3/PARP) and mitochondrial-damaged (Cyclophilin-D/DRP1/cytosolic-cytochrome-C) biomarkers displayed an identical pattern of BIA among the five groups (all p < 0.0001).

CONCLUSION

Combined CsA-Mel was superior to either CsA or Mel on protecting the brain against IR injury.

Consensus guidelines for the use and interpretation of angiogenesis assays

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

Intravenous administration of xenogenic adipose-derived mesenchymal stem cells (ADMSC) and ADMSC-derived exosomes markedly reduced brain infarct volume and preserved neurological function in rat after acute ischemic stroke

We tested the hypothesis that combined xenogenic (from mini-pig) adipose-derived mesenchymal stem cell (ADMSC) and ADMSC-derived exosome therapy could reduce brain-infarct zone (BIZ) and enhance neurological recovery in rat after acute ischemic stroke (AIS) induced by 50-min left middle cerebral artery occlusion. Adult-male Sprague-Dawley rats (n = 60) were divided equally into group 1 (sham-control), group 2 (AIS), group 3 [AIS-ADMSC (1.2×106 cells)], group 4 [AIS-exosome (100μg)], and group 5 (AIS-exosome-ADMSC). All therapies were provided intravenously at 3h after AIS procedure. BIZ determined by histopathology (by day-60) and brain MRI (by day-28) were highest in group 2, lowest in group 1, higher in groups 3 and 4 than in group 5, but they showed no difference between groups 3 and 4 (all p < 0.0001). By day-28, sensorimotor functional results exhibited an opposite pattern to BIZ among the five groups (p < 0.005). Protein expressions of inflammatory (inducible nitric oxide synthase/tumor necrosis factor-α/nuclear factor-κB/interleukin-1β/matrix metalloproteinase-9/plasminogen activator inhibitor-1/RANTES), oxidative-stress (NOX-1/NOX-2/oxidized protein), apoptotic (caspase-3/ Poly-ADP-ribose polymerase), and fibrotic (Smad3/transforming growth factor-β) biomarkers, and cellular expressions of brain-damaged (γ-H2AX+/ XRCC1-CD90+/p53BP1-CD90+), inflammatory (CD11+/CD68+/glial fibrillary acid protein+) and brain-edema (aquaporin-4+) markers showed a similar pattern of BIZ among the groups (all n < 0.0001). In conclusion, xenogenic ADMSC/ADMSC-derived exosome therapy was safe and offered the additional benefit of reducing BIZ and improving neurological function in rat AIS.

Protective Effect of Right Ventricular Mitochondrial Damage by Cyclosporine A in Monocrotaline-induced Pulmonary Hypertension

Background and Objectives

Mitochondria play a key role in the pathophysiology of heart failure and mitochondrial permeability transition pore (MPTP) play a critical role in cell death and a critical target for cardioprotection. The aim of this study was to evaluate the protective effects of cyclosporine A (CsA), one of MPTP blockers, and morphological changes of mitochondria and MPTP related proteins in monocrotaline (MCT) induced pulmonary arterial hypertension (PAH).

Methods

Eight weeks old Sprague-Dawley rats were randomized to control, MCT (60 mg/kg) and MCT plus CsA (10 mg/kg/day) treatment groups. Four weeks later, right ventricular hypertrophy (RVH) and morphological changes of right ventricle (RV) were done. Western blot and reverse transcription polymerase chain reaction (RT-PCR) for MPTP related protein were performed.

Results

In electron microscopy, CsA treatment prevented MCT-induced mitochondrial disruption of RV. RVH was significantly increased in MCT group compared to that of the controls but RVH was more increased with CsA treatment. Thickened medial wall thickness of pulmonary arteriole in PAH was not changed after CsA treatment. In western blot, caspase-3 was significantly increased in MCT group, and was attenuated in CsA treatment. There were no significant differences in voltage-dependent anion channel, adenine nucleotide translocator 1 and cyclophilin D expression in western blot and RT-PCR between the 3 groups.

Conclusions

CsA reduces MCT induced RV mitochondrial damage. Although, MPTP blocking does not reverse pulmonary pathology, it may reduce RV dysfunction in PAH. The results suggest that it could serve as an adjunctive therapy to PAH treatment.

FK506 protects heart function via increasing autophagy after myocardial infarction in mice

OBJECTIVE

To investigate the effect of tacrolimus (FK506) on myocardial infarction, and to further explore its function mechanism.

MATERIAL AND METHODS

C57BL/6J mice were randomly divided into three groups: the sham group, the control group and the FK506 group. Anterior descending branch ligation was conducted in the control and the FK506 groups, while sham operation was conducted in the sham group. Mice in the sham and the control groups were intragastrical administration with saline, while the FK506 group were with FK506. Heart function were detected by echocardiogram at 3rd day or 21st day after MI. Hearts were harvested at 3rd day or 21st day after MI for the detection of apoptosis, autophagy, mTOR and NF-κB pathway.

RESULTS

FK506 treatment increased survival rate and cardiac function in mice after MI. It decreased infarction area, inflammation reaction and apoptosis. To further study the mechanism of FK506 protection effect, we discovered it could increase autophagy via inhibit mTOR pathway.

CONCLUSION

FK506 protect heart function after MI as it improved myocardial cells autophagy process via inhibiting mTOR pathway.

Critical Issues for the Translation of Cardioprotection

The translation from numerous successful animal experiments on cardioprotection beyond that by reperfusion to clinical practice has to date been disappointing. Animal experiments often use reductionist approaches and are mostly performed in young and healthy animals which lack the risk factors, comorbidities, and comedications which are characteristics of patients suffering an acute myocardial infarction or undergoing cardiovascular surgery. Conceptually, it is still unclear by how much the time window for successful reperfusion is extended by preconditioning, and how long the duration of ischemia can be so that adjunct cardioprotection by postconditioning at reperfusion still protects. Experimental studies addressing long-term effects of adjunct cardioprotection beyond infarct size reduction, that is, on repair, remodeling, and mortality, are lacking. Technically, reproducibility and robustness of experimental studies are often limited. Grave faults in design and conduct of clinical trials have also substantially contributed to the failure of translation of cardioprotection to clinical practice. Cardiovascular surgery with ischemic cardioplegic arrest is only a surrogate of acute myocardial infarction and confounded by the choice of anesthesia, hypothermia, cardioplegia, and traumatic myocardial injury. Trials in patients with acute myocardial infarction have been performed on agents/interventions with no or inconsistent previous animal data and in patients who had either some reperfusion already at admission or were reperfused too late to expect any myocardial salvage. Of greatest concern is the lack of adequate phase II dosing and timing studies when rushing from promising proof-of-concept trials with surrogate end points such as infarct size to larger clinical outcome trials. Future trials must focus on interventions/agents with robust preclinical evidence, have solid phase II dosing and timing data, and recruit patients who have truly a chance to benefit from adjunct cardioprotection.

Combination of adipose-derived mesenchymal stem cells (ADMSC) and ADMSC-derived exosomes for protecting kidney from acute ischemia-reperfusion injury

BACKGROUND

In this study, we tested the hypothesis that a combined adipose-derived mesenchymal stem cell (ADMSC) and ADMSC-derived exosome therapy protected rat kidney from acute ischemia-reperfusion (IR) injury (i.e., ligation of both renal arteries for 1h and reperfusion for 72h prior to euthanization).

METHODS AND RESULTS

Adult-male SD rats (n=40) were equally categorized into group 1 (sham control), group 2 (IR), group 3 [IR+exosome (100μg)], group 4 [IR+ADMSC (1.2×10(6) cells)], and group 5 (IR-exosome-ADMSC). All therapies were performed at 3h after IR procedure from venous administration. By 72h, the creatinine level and kidney injury score were the lowest in group 1 and the highest in group 2, significantly higher in group 3 than in groups 4 and 5, and significantly higher in group 4 than in group 5 (all P<0.0001). The protein expression of inflammatory (TNF-α/NF-κB/IL-1β/MIF/PAI-1/Cox-2), oxidative-stress (NOX-1/NOX-2/oxidized protein), apoptotic (Bax/caspase-3/PARP), and fibrotic (Smad3/TGF-β) biomarkers showed an identical pattern, whereas the anti-apoptotic (Smad1/5, BMP-2) and angiogenesis (CD31/vWF/angiopoietin) biomarkers and mitochondrial cytochrome-C showed an opposite pattern of creatinine level among the five groups (all P<0.001). The microscopic findings of glomerular-damage (WT-1), renal tubular-damage (KIM-1), DNA-damage (γ-H2AX), inflammation (MPO/MIF/CD68) exhibited an identical pattern, whereas the podocyte components (podocin/p-cadherin/synaptopodin) displayed a reversed pattern of creatinine level (all P<0.0001).

CONCLUSION

Combined exosome-ADMSC therapy was superior to either one for protecting kidney from acute IR injury.

Enhanced protection against renal ischemia-reperfusion injury with combined melatonin and exendin-4 in a rodent model

We tested the hypothesis that combined treatment with melatonin, an anti-oxidant, and exendin-4, an anti-inflammatory agent, was superior to either alone for protecting the kidney from ischemia-reperfusion (IR) injury. Male adult Sprague-Dawley rats (n=40) were equally divided into group 1 (sham-operated control), group 2 (IR only, IR=1h/72h), group 3 (IR-exendin-4, 10 µg/kg at 30 min, 24 h, 48 h after IR procedure), group 4 (IR-melatonin, i.p. 50 mg at 30 min, then 20 mg at 6 and 18 h after IR procedure), and group 5 (combined IR-exendin-4-melatonin). All animals were sacrificed by 72 h after IR/sham procedure. The results showed that the kidney injury score, plasma creatinine, and blood urea nitrogen (BUN) levels were highest in group 2 and lowest in group 1, significantly higher in groups 3 and 4 than those in group 5 and significantly higher in group 3 than those in group 4 (all p < 0.001). The protein expressions of inflammatory (toll-like receptor 4, inducible nitric oxide synthase, interleukin-1β), apoptotic (mitochondrial Bax, cleaved caspase-3 and poly(ADP-ribose) polymerase, p53), podocyte integrity (E-cadherin, P-cadherin), and cell survival (phosphatidylinositol-3-kinase/AKT/mammalian target of rapamycin) biomarkers, as well the podocyte dysfunction biomarkers (Wnt1/Wnt4/β-catenin) displayed a pattern identical to that of creatinine level among the five groups (all p < 0.001). Microscopic findings demonstrated that podocyte dysfunction (Wnt1/Wnt4/β-catenin expression) and inflammatory (CD14 and F4/80-positively stained cells) biomarkers exhibited an identical pattern, whereas that of antioxidant (HO-1(+), NQO-1(+) cells) biomarkers showed an opposite pattern compared to that of creatinine level among the five groups (all p < 0.001). Combined melatonin-exendin-4 therapy offered an additional benefit in protecting the kidney from acute IR injury.

Decrease in plasma cyclophilin A concentration at 1 month after myocardial infarction predicts better left ventricular performance and synchronicity at 6 months: a pilot study in patients with ST elevation myocardial infarction

BACKGROUND

Cyclophilin A (CyPA) concentration increases in acute coronary syndrome. In an animal model of acute myocardial infarction, administration of angiotensin-converting-enzyme inhibitor was associated with lower left ventricular (LV) CyPA concentration and improved LV performance. This study investigated the relationships between changes in plasma CyPA concentrations and LV remodeling in patients with ST-elevation myocardial infarction (STEMI).

METHODS AND RESULTS

We enrolled 55 patients who underwent percutaneous coronary intervention for acute STEMI. Plasma CyPA, matrix metalloproteinase (MMP), interleukin-6 and high-sensitivity C-reactive protein concentrations were measured at baseline and at one-month follow-up. Echocardiography was performed at baseline and at one-, three-, and six-month follow-up. Patients with a decrease in baseline CyPA concentration at one-month follow-up (n = 28) had a significant increase in LV ejection fraction (LVEF) (from 60.2 ± 11.5% to 64.6 ± 9.9%, p < 0. 001) and preserved LV synchrony at six months. Patients without a decrease in CyPA concentration at one month (n = 27) did not show improvement in LVEF and had a significantly increased systolic dyssynchrony index (SDI) (from 1.170 ± 0.510% to 1.637 ± 1.299%, p = 0.042) at six months. Multiple linear regression analysis showed a significant association between one-month CyPA concentration and six-month LVEF. The one-month MMP-2 concentration was positively correlated with one-month CyPA concentration and LV SDI. Conclusions : Decreased CyPA concentration at one-month follow-up after STEMI was associated with better LVEF and SDI at six months. Changes in CyPA, therefore, may be a prognosticator of patient outcome.

Therapeutic potential of tacrolimus on acute myocardial infarction in minipigs: analysis with serial cardiac magnetic resonance and changes at histological and protein levels

This study investigates the therapeutic potential of intracoronary tacrolimus against acute myocardial infarction (AMI) in minipigs with serial cardiac magnetic resonance (CMR) and changes at histological and protein levels. Twelve minipigs subjected to permanent left anterior descending artery ligation were randomized as tac-treated group (n = 6, with intracoronary tacrolimus treatment) and controls (n = 6). CMR with cine and late gadolinium enhancement (LGE) studies were performed on postoperative days 2, 5, and 21. There were no significant differences in left ventricular function (LVF), contractility, and LGE between the two groups on day 2. On day 5, the tac-treated group showed a significantly higher ejection fraction, smaller infarct, and lower day-5/day-2 infarct ratio than controls. On day 21, the controls demonstrated further deterioration of LVF and infarct. Contrastingly, the tac-treated animals demonstrated preservation of LVF, contractility, significantly smaller infarct, and lower day-21/day-2 infarct ratios compared with those on day 5 and controls. The in vivo CMR results were correlated with in vitro findings on histology, immunostaining, and Western blotting which revealed significantly less fibrosis, higher vascularities, less CD68+ and CD40+ inflammatory cells, lower expressions of inflammatory (MMP-9, NF-κB, and TNF-α), and apoptotic (Bax, Caspase-3, c-PARP) biomarkers, respectively, in tac-treated AMI minipigs than controls.

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.

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.

Exendin-4 and sitagliptin protect kidney from ischemia-reperfusion injury through suppressing oxidative stress and inflammatory reaction

BACKGROUND

This study tested the hypothesis that exendin-4 and sitagliptin can effectively protect kidney from acute ischemia-reperfusion (IR) injury.

METHODS

Adult SD-rats (n = 48) equally divided into group 1 (sham control), group 2 (IR injury), group 3 [IR + sitagliptin 600 mg/kg at post-IR 1, 24, 48 hr)], and group 4 [IR + exendin-4 10 μm/kg at 1 hr after procedure] were sacrificed after 24 and 72 hrs (n = 6 at each time from each group) following clamping of bilateral renal pedicles for 60 minutes (groups 2-4).

RESULTS

Serum creatinine level and urine protein to creatinine ratio were highest in group 2 and lowest in group 1 (all p < 0.001) without notable differences between groups 3 and 4. Kidney injury score, expressions of inflammatory biomarkers at mRNA (MMP-9, TNF-α, IL-1β, PAI-1), protein (TNF-α, NF-κB and VCAM-1), and cellular (CD68+) levels in injured kidneys at 24 and 72 hr showed an identical pattern compared to that of creatinine level in all groups (all p < 0.0001). Expressions of oxidized protein, reactive oxygen species (NOX-1, NOX-2), apoptosis (Bax, caspase-3 and PARP), and DNA damage marker (γH2AX+) of IR kidney at 24 and 72 hrs exhibited a pattern similar to that of inflammatory mediators among all groups (all p < 0.01). Renal expression of glucagon-like peptide-1 receptor, and anti-oxidant biomarkers at cellular (GPx, GR) and protein (NQO-1, HO-1, GPx) levels at 24 and 72 hr were lowest in group 1, significantly lower in group 2 than in groups 3 and 4 (all p < 0.01).

CONCLUSION

Exendin-4 and sitagliptin provided significant protection for the kidneys against acute IR injury.

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.

Mechanisms involved in postconditioning protection of cardiomyocytes against acute reperfusion injury

Experimental and clinical studies demonstrated that postconditioning confers protection against myocardial ischemia/reperfusion injury. However the underlying cellular mechanisms responsible for the beneficial effect of postconditioning are still poorly understood. The aim of the present study was to examine the role of cytosolic and mitochondrial Ca(2+)-handling. For this purpose adult rat cardiomyocytes were subjected to simulated in vitro ischemia (glucose-free hypoxia at pH6.4) followed by simulated reperfusion with a normoxic buffer (pH7.4; 2.5 mmol/L glucose). Postconditioning, i.e., 2 repetitive cycles of normoxic (5s) and hypoxic (2.5 min) superfusion, was applied during the first 5 min of reoxygenation. Mitochondrial membrane potential (ΔΨm), cytosolic and mitochondrial Ca(2+) concentrations, cytosolic pH and necrosis were analysed applying JC-1, fura-2, fura-2/manganese, BCECF and propidium iodide, respectively. Mitochondrial permeability transition pore (MPTP) opening was detected by calcein release. Hypoxic treatment led to a reduction of ΔΨm, an increase in cytosolic and mitochondrial Ca(2+) concentration, and acidification of cardiomyocytes. During the first minutes of reoxygenation, ΔΨm transiently recovered, but irreversibly collapsed after 7 min of reoxygenation, which was accompanied by MPTP opening. Simultaneously, mitochondrial Ca(2+) increased during reperfusion and cardiomyocytes developed spontaneous cytosolic Ca(2+) oscillations and severe contracture followed by necrosis after 25 min of reoxygenation. In postconditioned cells, the collapse in ΔΨm as well as the leak of calcein, the increase in mitochondrial Ca(2+), cytosolic Ca(2+) oscillations, contracture and necrosis were significantly reduced. Furthermore postconditioning delayed cardiomyocyte pH recovery. Postconditioning by hypoxia/reoxygenation was as protective as treatment with cyclosporine A. Combining cyclosporine A and postconditioning had no additive effect. The data of the present study demonstrate that postconditioning by hypoxia/reoxygenation prevents reperfusion injury by limiting mitochondrial Ca(2+) load and thus opening of the MPTP in isolated cardiomyocytes. These effects seem to be supported by postconditioning-induced delay in pH recovery and suppression of Ca(2+) oscillations.

Combination of cilostazol and clopidogrel attenuates rat critical limb ischemia

BACKGROUND AND AIM

Procedural failure and untoward clinical outcomes after surgery remain problematic in critical limb ischemia (CLI) patients. This study tested a clopidogrel-cilostazol combination treatment compared with either treatment alone in attenuating CLI and improving CLI-region blood flow in rats.

METHODS

Male Sprague-Dawley rats (n = 40) were equally divided into five groups: control, CLI induction only, CL I + cilostazol (12.0 mg/day/kg), CLI + clopidogrel (8.0 mg/kg/day) and CLI + combined cilostazol-clopidogrel. After treatment for 21 days, Laser Doppler imaging was performed.

RESULTS

On day 21, the untreated CLI group had the lowest ratio of ischemic/normal blood flow (p < 0.001). Inflammation measured by VCAM-1 protein expression; oxidative stress; PAI-1, MMP-9 and TNF-α mRNA expressions; and immunofluorescence staining (IF) of CD68+ cells was lower with combined treatment than with the other treatments, and lower in the two single-treatment groups than the untreated CLI group (all p < 0.01). Anti-inflammatory mRNA expression of interleukin-10, and eNOS showed a reverse pattern among these groups. Apoptosis measured by Bax, caspase-3 and PARP; and muscle damage measured by cytosolic cytochrome-C, and serum and muscle micro-RNA-206 were all lowest with combination treatment, and the two single-treatment groups showed lower values than the untreated group (all p < 0.001). Angiogenesis measured by eNOS, IF staining of CD31+ and vWF + cells; and number of vessels in CLI region were highest with combination treatment and higher in the single-treatment groups than the untreated group (all p < 0.001).

CONCLUSION

Combined cilostazol-clopidogrel therapy is superior to either agent alone in improving ischemia in rodent CLI.

Effect of tacrolimus on myocardial infarction is associated with inflammation, ROS, MAP kinase and Akt pathways in mini-pigs

AIM

This study tested the hypothesis that tacrolimus therapy limited left ventricular (LV) infarct and remodeling by suppressing the inflammatory response, oxidative stress and regulating the mitogen-activated protein kinase (MAPK) and Akt signaling pathways in an acute myocardial infarction (AMI) mini-pig model by ligating the left anterior descending coronary artery (LAD).

METHODS

Twelve male mini-pigs were equally randomized into AMI treated by saline (3.0 mL) (AMI(S)), and AMI treated by tacrolimus (0.5 mg) (AMI(T)). Thirty minutes after the procedure, intra-LAD injections were performed just beyond the ligation.

RESULTS

Inflammatory biomarkers at transcription or protein levels [matrix metalloproteinase (MMP9), plasminogen activator inhitor-1, tumor necrotic factor (TNF-α), nuclear factor (NF)-κB] and the cellular level (CD40+ cells) were markedly higher in AMI(S) than in AMI(T) animals (all p<0.001). Fibrosis biomarkers at the protein level (α-smooth muscle actin, transforming growth factor-β) and Sirius-red staining were notably higher in AMI(S) than in AMI(T) animals (all p<0.03). Antioxidant biomarkers at protein or transcription levels (heme oxygenase-1, quinone oxidoreductase-1, glutathione reductase, glutathione peroxidase) were significantly higher in AMI(S) than in AMI(T) animals (all p<0.01). Protein expressions of ERK1, p38 MAPK and Akt were markedly increased in AMI(S) compared to AMI(T) animals (all p<0.001). Significantly aggravated LV infarction and remodeling were noted in AMI(S) compared to AMI(T) animals, whereas LV ejection fraction was markedly decreased in AMI(S) compared to AMI(T) animals (all p<0.001).

CONCLUSIONS

Intra-coronary administration of tacrolimus attenuated inflammation and MAPK signaling, limited infarct size, and preserved LV function.

Effect of obesity reduction on preservation of heart function and attenuation of left ventricular remodeling, oxidative stress and inflammation in obese mice

BACKGROUND

Obesity is an important cardiovascular risk factor. This study tested the effect of obesity reduction on preserving left ventricular ejection fraction (LVEF) and attenuating inflammation, oxidative stress and LV remodeling in obese mice.

METHODS AND RESULTS

Eight-week-old C57BL/6 J mice (n=24) were equally divided into control (fed a control diet for 22 weeks), obesity (high-fat diet, 22 weeks), and obese reduction (OR) (high-fat diet, 14 weeks; then control diet, 8 weeks). Animals were sacrificed at post 22-week high-fat diet and the LV myocardium collected. Heart weight, body weight, abdominal-fat weight, total cholesterol level and fasting blood glucose were higher in obesity than in control and OR (all p<0.001). Inflammation measured by mRNA expressions of IL-6, MMP-9, PAI-1 and leptin and protein expression of NF-κB was higher, whereas anti-inflammation measured by mRNA expressions of adiponectin and INF-γ was lower in obesity than in control and OR (all p<0.003). Oxidative protein expressions of NOX-1, NOX-2 and oxidized protein were higher, whereas expression of anti-oxidant markers HO-1 and NQO-1 were lower (all p<0.01); and apoptosis measured by Bax and caspase 3 was higher, whereas anti-apoptotic Bcl-2 was lower in obesity as compared with control and OR (all p<0.001). The expressions of fibrotic markers phosphorylated Smad3 and TGF-β were higher, whereas expression of anti-fibrotic phosphorylated Smad1/5 and BMP-2 were lower (all p<0.02); and LVEF was lower, whereas the LV remodeling was higher in obesity than in control and OR (all p<0.001).

CONCLUSION

Impaired LVEF, enhanced LV remodeling, inflammation, fibrosis, oxidative stress and apoptosis were reversed by reduction in mouse obesity.

Impact of obesity control on circulating level of endothelial progenitor cells and angiogenesis in response to ischemic stimulation

Background and aim

We tested the hypothesis that obesity reduced circulating number of endothelial progenitor cells (EPCs), angiogenic ability, and blood flow in ischemic tissue that could be reversed after obesity control.

Methods

8-week-old C57BL/6J mice (n = 27) were equally divided into group 1 (fed with 22-week control diet), group 2 (22-week high fat diet), and group 3 (14-week high fat diet, followed by 8-week control diet). Critical limb ischemia (CLI) was induced at week 20 in groups 2 and 3. The animals were sacrificed at the end of 22 weeks.

Results

Heart weight, body weight, abdominal fat weight, serum total cholesterol level, and fasting blood sugar were highest in group 2 (all p < 0.001). The numbers of circulating EPCs (C-kit/CD31+, Sca-1/KDR + and CXCR4/CD34+) were lower in groups 1 and 2 than in group 3 at 18 h after CLI induction (p < 0.03). The numbers of differentiated EPCs (C-kit/CD31+, CXCR4/CD34+ and CD133+) from adipose tissue after 14-day cultivation were also lowest in group 2 (p < 0.001). Protein expressions of VCAM-1, oxidative index, Smad3, and TGF-β were higher, whereas the Smad1/5 and BMP-2, mitochondrial cytochrome-C SDF-1α and CXCR4 were lower in group 2 than in groups 1 and 3 (all p < 0.02). Immunofluorescent staining of CD31+ and vWF + cells, the number of small vessel (<15 μm), and blood flow through Laser Doppler scanning of ischemic area were lower in group 2 compared to groups 1 and 3 on day 14 after CLI induction (all p < 0.001).

Conclusion

Obesity suppressed abilities of angiogenesis and recovery from CLI that were reversed by obesity control.

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.

Cell death pathways in acute ischemia/reperfusion injury

The consequence of myocardial ischemia is energetic stress, while reperfusion is accompanied by abrupt ionic shifts and considerable oxidative stress. Cells die by apoptotic and necrotic pathways. After the acute injury, the healing myocardium is subject to biomechanical stress and inflammation, which can trigger a smaller but more sustained wave of cell death, as well as changes in the metabolic and functional characteristics of surviving cells. The goal of cardioprotection is to prevent cell death during the acute injury as well as to modulate the detrimental processes that ensue during remodeling. This review will focus on acute injury, and the central premise is that mitochondria are the key determinant of cardiomyocyte fate.

Long term stabilization of expanding aortic aneurysms by a short course of cyclosporine A through transforming growth factor-beta induction

Abdominal aortic aneurysms (AAAs) expand as a consequence of extracellular matrix destruction, and vascular smooth muscle cell (VSMC) depletion. Transforming growth factor (TGF)-beta 1 overexpression stabilizes expanding AAAs in rat. Cyclosporine A (CsA) promotes tissue accumulation and induces TGF -beta1 and, could thereby exert beneficial effects on AAA remodelling and expansion. In this study, we assessed whether a short administration of CsA could durably stabilize AAAs through TGF-beta induction. We showed that CsA induced TGF-beta1 and decreased MMP-9 expression dose-dependently in fragments of human AAAs in vitro, and in animal models of AAA in vivo. CsA prevented AAA formation at 14 days in the rat elastase (diameter increase: CsA: 131.9±44.2%; vehicle: 225.9±57.0%, P = 0.003) and calcium chloride mouse models (diameters: CsA: 0.72±0.14 mm; vehicle: 1.10±0.11 mm, P = .008), preserved elastic fiber network and VSMC content, and decreased inflammation. A seven day administration of CsA stabilized formed AAAs in rats seven weeks after drug withdrawal (diameter increase: CsA: 14.2±15.1%; vehicle: 45.2±13.7%, P = .017), down-regulated wall inflammation, and increased αSMA-positive cell content. Co-administration of a blocking anti-TGF-beta antibody abrogated CsA impact on inflammation, αSMA-positive cell accumulation and diameter control in expanding AAAs. Our study demonstrates that pharmacological induction of TGF-beta1 by a short course of CsA administration represents a new approach to induce aneurysm stabilization by shifting the degradation/repair balance towards healing.

Combination of cyclosporine and erythropoietin improves brain infarct size and neurological function in rats after ischemic stroke

BACKGROUND

This study tested the superiority of combined cyclosporine A (CsA)-erythropoietin (EPO) therapy compared with either one in limiting brain infarction area (BIA) and preserving neurological function in rat after ischemic stroke (IS).

METHODS

Fifty adult-male SD rats were equally divided into sham control (group 1), IS plus intra-peritoneal physiological saline (at 0.5/24/48 h after IS) (group 2), IS plus CsA (20.0 mg/kg at 0.5/24h, intra-peritoneal) (group 3), IS plus EPO (5,000IU/kg at 0.5/24/48h, subcutaneous) (group 4), combined CsA and EPO (same route and dosage as groups 3 and 4) treatment (group 5) after occlusion of distal left internal carotid artery.

RESULTS

BIA on day 21 after acute IS was higher in group 2 than in other groups and lowest in group 5 (all p < 0.01). The sensorimotor functional test showed higher frequency of left turning in group 2 than in other groups and lowest in group 5 (all p < 0.05). mRNA and protein expressions of apoptotic markers and number of apoptotic nuclei on TUNEL were higher in group 2 than in other groups and lowest in group 1 and 5, whereas the anti-apoptotic markers exhibited an opposite trend (all p < 0.05). The expressions of inflammatory and oxidized protein were higher in group 2 than in other groups and lowest in group 1 and 5, whereas anti-inflammatory markers showed reversed changes in group 1 and other groups (all p < 0.05). The number of aquaporin-4+ and glial fibrillary acid protein+ stained cells were higher in group 2 as compared to other groups and lowest in groups 1 and 5 (all p < 0.01).

CONCLUSION

combined treatment with CsA and EPO was superior to either one alone in protecting rat brain from ischemic damage after IS.

Cyclosporine A, 2.5 mg/kg, does not reduce myocardial infarct size in a porcine model of ischemia and reperfusion

BACKGROUND

In recent years, cyclosporine A (CsA) has emerged as a promising therapy to limit myocardial ischemic-reperfusion injury, presumably by inhibiting the opening of the mitochondrial permeability transition pore. Results from different large animal models are conflicting, however, with failure to prove beneficial effects of 10 mg/kg CsA administered at reperfusion. Recently, a small clinical study using a bolus of 2.5 mg/kg CsA showed promising but not unequivocal results. The aim of the present study was to estimate the magnitude of a possible infarct reduction with the use of the latter regimen in a closed-chest porcine model for ischemia and reperfusion. Materials and

METHODS

Pigs underwent catheterization with balloon occlusion of the left descending coronary artery for 40 minutes, followed by reperfusion for 4 hours. They were randomized to receive an intravenous bolus 7 minutes before reperfusion of either 2.5 mg/kg CsA (n = 12) or saline (control, n = 11). Hearts were stained to quantify area at risk and infarct size.

RESULTS

Throughout the experiment, there were no differences between the groups in baseline characteristics or hemodynamic variables. CsA treatment did not reduce infarct size as a proportion of area at risk compared with control (51% ± 6% and 54% ± 6%, respectively, P = .75).

CONCLUSION

In a closed-chest porcine model for myocardial ischemia and reperfusion injury, 2.5 mg/kg CsA administered before reperfusion did not reduce infarct size.