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Fetal cutaneous wound closure and repair differ from that in adulthood. In this work, we identify an oxidant stress sensor protein, nonselenocysteine-containing phospholipid hydroperoxide glutathione peroxidase (NPGPx), that is abundantly expressed in normal fetal epidermis (and required for fetal wound closure), though not in adult epidermis, but is variably re-induced upon adult tissue wounding. NPGPx is a direct target of the miR-29 family. Following injury, abundance of miR-29 is lowered, permitting a prompt increase in NPGPx transcripts and protein expression in adult wound-edge tissue. NPGPx expression was required to mediate increased keratinocyte migration induced by miR-29 inhibition in vitro and in vivo. Increased NPGPx expression induced increased SOX2 expression and β-catenin nuclear localization in keratinocytes. Augmenting physiologic NPGPx expression via experimentally induced miR-29 suppression, using cutaneous tissue nanotransfection or targeted lipid nanoparticle delivery of anti-sense oligonucleotides, proved to be sufficient to overcome the deleterious effects of diabetes on this specific pathway to enhance tissue repair.

Objectives: Intra-abdominal sepsis is commonly diagnosed in the surgical population and remains the second most common cause of sepsis overall. Sepsis-related mortality remains a significant burden in the intensive care unit despite advances in critical care. Nearly a quarter of the deaths in people with heart failure are caused by sepsis. We have observed that overexpression of mammalian Pellino-1 (Peli1), an E3 ubiquitin ligase, causes inhibition of apoptosis, oxidative stress, and preservation of cardiac function in a myocardial infarction model. Given these manifold applications, we investigated the role of Peli1 in sepsis using transgenic and knockout mouse models specific to this protein. Therefore, we aimed to explore further the myocardial dysfunction seen in sepsis through its relation to the Peli 1 protein by using the loss of function and gain-of-function strategy. Methods: A series of genetic animals were created to understand the role of Peli1 in sepsis and the preservation of heart function. Wild-type, global Peli1 knock out (Peli1−/−), cardiomyocyte-specific Peli1 deletion (CP1KO), and cardiomyocyte-specific Peli1 overexpressing (alpha MHC (αMHC) Peli1; AMPEL1Tg/+) animals were divided into sham and cecal ligation and puncture (CLP) surgical procedure groups. Cardiac function was determined by two-dimensional echocardiography pre-surgery and at 6- and 24-h post-surgery. Serum IL-6 and TNF-alpha levels (ELISA) (6 h), cardiac apoptosis (TUNEL assay), and Bax expression (24 h) post-surgery were measured. Results are expressed as mean ± S.E.M. Results: AMPEL1Tg/+ prevents sepsis-induced cardiac dysfunction assessed by echocardiographic analysis, whereas global and cardiomyocyte-specific deletion of Peli1 shows significant deterioration of cardiac functions. Cardiac function was similar across the sham groups in all three genetically modified mice. ELISA assay displayed how Peli 1 overexpression decreased cardo-suppressive circulating inflammatory cytokines (TNF-alpha, IL-6) compared to both the knockout groups. The proportion of TUNEL-positive cells varied according to Peli1 expression, with overexpression (AMPEL1Tg/+) leading to a significant reduction and Peli1 gene knockout (Peli1−/− and CP1KO) leading to a significant increase in their presence. A similar trend was also observed with Bax protein expression. The improved cellular survival associated with Peli1 overexpression was again shown with the reduction of oxidative stress marker 4-Hydroxy-2-Nonenal (4-HNE). Conclusion: Our results indicate that overexpression of Peli1 is a novel approach that not only preserved cardiac function but reduced inflammatory markers and apoptosis following severe sepsis in a murine genetic model.

Our earlier studies showed that inhibiting prolyl-4-hydroxylase enzymes (PHD-1 and PHD-3) improves angiogenesis, heart function, and limb perfusion in mouse models via stabilizing hypoxia-inducible transcription factor-alpha (HIF-1α). The present study explored the effects of the prolyl-4-hydroxylase enzyme, PHD-2, on ischemic heart failure using cardiac-specific PHD-2 gene knockout (KO) mice (PHD2 -/- ).Adult wild-type (WT) and PHD2 -/- mice, 8-12 weeks old, were subjected to myocardial infarction (MI) by irreversibly ligating the left anterior descending (LAD) coronary artery. All sham group mice underwent surgery without LAD ligation. Animals were divided into 4 groups: (1) wild-type sham (WTS); (2) wild-type myocardial infarction (WTMI); (3) PHD2KO sham (PHD2 -/- S); (4) PHD2KO myocardial infarction (PHD2 -/- MI). Left ventricular tissue samples collected at various time points after surgery were used for microRNA expression profiling, Western blotting, and immunohistochemical analysis.Volcano plot analysis revealed 19 differentially-expressed miRNAs in the PHD2 -/- MI group compared with the WTMI group. Target analysis using Ingenuity Pathway Analysis showed several differentially regulated miRNAs targeting key signaling pathways such as Akt, VEGF, Ang-1, PTEN, apoptosis, and hypoxia pathways. Western blot analysis showed increased HIF-1α, VEGF, phospho-AKT, β-catenin expression and reduced Bax expression for the PHD2 -/- MI group compared with the WTMI group. Echocardiographic analysis showed preserved heart functions, and picrosirius red staining revealed decreased fibrosis in PHD2 -/- MI compared with the WTMI group.PHD2 inhibition showed preserved heart function, enhanced angiogenic factor expression, and decreased apoptotic markers after MI. Overall, cardiac PHD2 gene inhibition is a promising candidate for managing cardiovascular diseases.

Introduction: Increased production of reactive oxygen species contributes to the etiology of diabetic complications. It acts as an intracellular antioxidant by scavenging reactive oxygen species (ROS) and protect the cells against oxidative stress and cell death. Hypothesis: To determine the long-term effect of streptozotocin (STZ) induced type 1 diabetes on aging Trx-1 transgenic mice related to survivability, heart function, fibrosis, and apoptosis up to 180 days (d) compared to its corresponding wild-type (WT C57Bl/6J). Method: WT and Trx-1 overexpressed mice (Trx-1 Tg/+ ) (8-12 weeks old) were injected with STZ (i.p. 50mg/kg.body weight(bw)-male; 75mg/kg.bw-female for 5 consecutive days) for induction of diabetes (Dia). Fasting blood sugar level (FBS) was measured 30d after the final injection, and FBS >220mg/dL is used as the cut-off for diabetes. Echocardiography, Survival, FBS measurements were performed on 30, 60, 90, 120, 150, and 180d. Immunohistochemistry was performed on heart tissues (30, 90, and 180d). Results: Dia-Trx-1 Tg/+ mice maintained EF at 60d (61.14±2.3%), 120d (56.1±1.94%) and 180d (60.8±4.3%), when compared to 30d (64.4±1.94%) representing preserved cardiac functions. On the other hand, Dia-WT mice show significant progressive depression of EF at 60d (53.8±1.9%), 120d (48.8±2.1%), and 180d (48.9±1.5%), (pTg/+ mice show significantly higher EF than their corresponding Dia-WT counterparts at each time point measured after diabetic induction (n=8-12, pTg/+ mice (n=71) also exhibited increased survival rate over Dia-WT (n=47) counterparts with a median survival of 150 days compared to 60 days (Log Rank test: p=0.004). Dia-Trx-1 Tg/+ mice also showed a significant reduction in cardiac fibrosis (4.18±1.08% vs. 17.5±5.1%; p=0.03, n=4) and TUNEL positive cells (3.81±1.49 vs. 7.66±1.46; p=0.03, n=4) when compared to their counterpart (Dia-WT) after 180d of diabetes. Conclusion: These results show that Trx-1 Tg/+ mice preserved cardiac functions, increased survival, decreased apoptosis and fibrosis up to 180d under diabetic conditions, and hence suggesting Trx-1 based treatment strategy could prevent heart failure in aging.

Introduction: Sepsis remains a significant cause of mortality in the intensive care unit till today. Recent research suggests nearly one in four deaths in people with heart failure is caused by sepsis. Overexpression of mammalian Pellino-1 (Peli1), a E3 ubiquitin ligase, causes inhibition of apoptosis, oxidative stress, and preservation of cardiac function in a myocardial infarction model. Therefore, in the present study, we explored the possibility to overcome sepsis mediated heart failure by overexpressing Peli1 (AMPEL1Tg/+) in a mouse model of severe sepsis. Methods: C57BL/6J (WT) and AMPEL1 Tg/+ mice were divided into Wild-type sham (WTS), Wild-type Cecal Ligation and Puncture (WTCLP), AMPEL1 Tg/+ sham (AMPEL1 Tg/+ S) and AMPEL1 Tg/+ CLP. Cardiac function (LVEF, FS) by two-dimensional echocardiography was assessed pre-procedure, at 6, and 24 hours post-surgery. Serum IL-6 and TNF-alpha (ELISA) at 6 hours and cardiac apoptosis (TUNEL assay) at 24 hours were measured. Results are expressed as mean ± SEM. Results: Analysis of echocardiographic parameters (EF, FS) preoperatively and among the sham groups were similar however there was significant preservation of post-procedure LVEF (%) in the AMPEL1 Tg/+ CLP at the 6 hour (AMPEL1 Tg/+ :52.7 ± 3.71 vs WT:40.7 ±2.46, p=0.013, n=10-11) and 24-hour time point (AMPEL1 Tg/+ :63.1 ± 1.63 vs WT:49.3 ± 4.41, p=0.002, n=9-11) compared to WT. Similar trend was observed in estimation of FS (%) at 6 hours (AMPEL1 Tg/+ :26.3 ± 2.22 vs WT:19.3 ±1.37, p=0.014, n=10-11) and 24 hours (AMPEL1 Tg/+ :32.4 ± 1.89 vs WT:24.4 ± 2.67, p=0.031, n=9-11). A marked decrease in serum IL-6 (AMPEL1 Tg/+ :259.7 ± 18.70 vs WT:483.2 ± 24.01, pTg/+ :86.89 ± 14.36 vs WT:161.8 ± 20, p=0.012, n=6, pg/mL) was observed in the AMPEL1 Tg/+ CLP at 6 hours. The preserved cardiac function in CLP was further supported by a noticeable decrease in cardiac apoptosis (% TUNEL positive cells) at 24 hours in the AMPEL1 Tg/+ CLP group (4.7 ± 0.94 vs 11.7 ± 2.82, p=0.040, n=6,) compared to WTCLP. Conclusions: Thus, Peli1 overexpression is a novel approach that preserved cardiac function, reduced inflammatory markers, and apoptosis following severe sepsis in a murine genetic model.

Introduction: Ischemic heart disease is the leading cause of death in adults in the US. We have shown that overexpression of E3 ligase Pellino1 (Peli1) increased vessel density, triggered anti-apoptotic signaling, and preserved cardiac function in the infarcted myocardium. In the present study, we aimed to explore whether the loss of Peli1 function in cardiomyocytes has any effect on cardiac function using a genetically-modified murine myocardial infarction (MI) model. Methods: Wild type (WT) and cardiomyocyte-specific Peli1 knockout (CP1KO -/- ) mice were divided into 4 groups [wild-type-sham (WTS), CP1KO -/- sham (CP1KO -/- S), WTMI and CP1KO -/- MI] to undergo either left anterior descending artery ligation or sham surgery. Phosphorylation of Mitogen-Activated Protein Kinase-Activated Protein Kinase-2 (p-MK2) and expression of VEGF, Bcl2, and cIAP2 were quantified by Western blot analysis. Cardiac function by two-dimensional echocardiography was performed at 30 days post-op to assess ejection fraction (EF), fractional shortening (FS), left ventricular internal diameter in both systole and diastole (LVIDs and LVIDd). Results: We observed no significant change in cardiac functions between WTS and CP1KO-/-S group. However, in MI groups, CP1KO -/- mice showed significant loss of systolic functions, represented by both EF (26.60%±2.340 vs. 33.46%±1.84; p-/- group compared to WT mice. Similarly, expression of VEGF (p=0.0227), BCl-2 (p=0.0073) and cIAP2 (p=0.0483) was also found to be significantly downregulated in CP1KO -/- group compared to WTMI group at 4-day post-MI. We also analyzed oxidative stress marker, 3-NT, which was significantly upregulated (p=0.0001) in CP1KO mice compared to WTMI. Conclusion: Loss of Peli1 in cardiomyocyte results in the impairment of cardiac function along with increased oxidative stress, reduced angiogenic and survival protein expression, which suggests Peli1 plays an important role in the cardiomyocyte signaling during myocardial infarction.

Introduction: Peripheral vascular disease (PVD) is a major cause of morbidity in the US. Vascular endothelial growth factor (VEGF) induces angiogenesis through Fetal-Liver Kinase-1 (Flk-1 or VEGFR-2), an endothelial tyrosine kinase receptor which activates a downstream signaling cascade involving MAPKAPKinase2 (MK2). We have demonstrated poorer recovery in hind limb ischemia models using Flk-1 +/- and MK2 -/- knockout mice compared to wild type mice. We also demonstrated overespression of Pellino1 (Peli1), an E3 Ligase, can attenuate ischemic damage and increase neovascularization and survivability of ischemic myocardium and skin flaps. Therefore, in this study we aim to show if Peli1 gene therapy can help rescue function in Flk-1 +/- and MK2 -/- after femoral artery ligation. Methods: 8-12 week-old Flk-1 +/- and MK2 -/- mice were subjected to femoral artery ligation of the right hind limb and treated with either adenovirus carrying Peli1 (Ad.Peli1) or LacZ (Ad.LacZ), for a total of 4 groups: Flk-1 +/- Ad.LacZ, Flk-1 +/- Ad.Peli1, MK2 -/- Ad.LacZ and MK2 -/- Ad.Peli1. Perfusion was assessed with laser Doppler imaging preop and on days 0, 3, 7, 14, 21 and 28. Extent of limb ischemia was also quantified using a standardized scoring scale (0 = no ischemia, to 8 = full limb amputation). Results: Perfusion was significantly higher in the Flk-1 +/- Ad.Peli1 group compared to Flk-1 +/- Ad.LacZ on days 7 (0.19±0.03 vs 0.08±0.02), 14 (0.41±0.07 vs 0.09±0.03), 21 (0.33±0.05 vs 0.14±0.05) and 28 (0.31±0.05 vs 0.15±0.02) (n=9-15, p+/- Ad.Peli1 group when compared to Flk-1 +/- Ad.LacZ on days 3 (1.89±0.56 vs 4.88±0.85), 7 (2.11±0.54 vs 5.69±0.92), 14 (2.18±0.52 vs 6.31±1.02), 21 (1.83±0.58 vs 6.50±1.05) and 28 (1.67±0.62 vs 6.50±1.05) (n=8-9, p-/- Ad.Peli1 and MK2 -/- Ad.LacZ groups. Values are mean +/- SEM. Conclusions: Treatment with Ad.Peli1 resulted in improved perfusion and decreased tissue ischemia in Flk-1 +/- mice. These results were not paralleled in MK2 -/- mice suggesting that Peli1 acts upstream to MK2 but downstream of VEGF/Flk-1. Overall, Peli1 gene therapy is a promising candidate in the management of PVD.

Background Heat shock protein A12B expressed in endothelial cells is important and required for angiogenesis to form functional vessels in ischemic tissue. We have previously shown the cardioprotective effects of heat shock protein A12B overexpression in a rat model of diabetic myocardial infarction. In this study, we aim to explore the role of heat shock protein A12B in a surgically-induced murine hind-limb ischemia model. Materials and Methods Adult 8- to 12-week-old C57BL/6J mice were divided into 2 groups: treated with Adeno.LacZ (control group) and with Adeno.HSPA12B (experimental group) and, with both groups subjected to right femoral artery ligation. Immediately after surgery, mice in both groups received either Adeno.HSPA12B or Adeno.LacZ (1 × 109 plaque forming units) in both the semimembranosus and gastrocnemius muscles of the right limb. The left limb served as the internal control. Both groups underwent serial laser Doppler imaging preoperatively, and again postoperatively until 28 days. Immunohistochemical analysis was performed 3 and 28 days post-surgery. Results Mice in the Adeno.HSPA12B gene therapy group showed improved motor function and a significantly higher blood perfusion ratio on postoperative days 21 and 28, along with better motor function. Immunohistochemical analysis showed increased expression of vascular endothelial growth factor, thioredoxin-1, heme oxygenase, and hypoxia-inducible factor 1α, along with a decreased expression of A-kinase-anchoring protein 12 and thioredoxin-interacting protein levels. The Adeno.HSPA12B-treated group also showed increased capillary and arteriolar density and an increased capillary-myocyte ratio, along with reduced fibrosis compared to the Adeno.LacZ group. Conclusion Our study demonstrates that targeted Adeno.HSPA12B gene delivery into ischemic muscle enhances perfusion and angiogenic protein expression. This molecule shows promise for the management of peripheral vascular disease as a potential target for clinical trials and subsequent drug therapy.

Despite recent advancements, mortality due to coronary heart disease (CHD) remains high. Recently, the use of tissue-engineered grafts and scaffolds has emerged as a candidate for supporting the myocardium after an ischemic event. Resveratrol is a naturally occurring plant-based non-flavonoid polyphenolic compound found in many natural foods, including grapes and red wine. We embedded resveratrol in a polycaprolactone (PCL) scaffold and evaluated the cardio-therapeutic effects in a murine model of myocardial infarction (MI), with animals being grouped into Sham (S), Myocardial Infarction (MI), MI + PCL, and MI + PCL-Resveratrol (MI + PCL-R). After 4 and 8 weeks, echocardiography was performed to assess ejection fraction (EF) and fractional shortening (FS), which was followed by immunohistochemistry and immunofluorescence analysis at 8 weeks. The MI + PCL-R group showed a significant improvement in EF and FS compared with the MI + PCL group at 4 and 8-weeks post-surgery. PCL-R scaffolds treated hearts revealed decreased inflammatory cell infiltration, improved collagen extracellular matrix (ECM) secretion and blood vessel network formation following MI. The immunofluorescence analysis revealed resveratrol-loaded scaffolds promote increased expression of cTnT, Cx-43, Trx-1, and VEGF proteins. This study reports resveratrol-mediated rescue of ischemic myocardium when delivered through a biodegradable polymeric scaffold system after MI.

In the present study, we aimed to explore the functional role of Pellino-1 (Peli1) in inducing neovascularization after myocardial infarction (MI) and hindlimb ischemia (HLI) using Peli1 global knockout mice (Peli1−/−). Recently we have shown that Peli1, an E3 ubiquitin ligase, induce angiogenesis and improve survivability, with decreased necrosis of ischemic skin flaps. Peli1fl/fl and Peli1−/− mice were subjected to either permanent ligation of the left anterior descending coronary artery (LAD) or sham surgery (S). Tissues from the left ventricular risk area were collected at different time points post-MI. In addition, Peli1fl/fl and Peli1−/− mice were also subjected to permanent ligation of the right femoral artery followed by motor function scores, Doppler analysis for blood perfusion and immunohistochemical analysis. Global Peli1 knockout exacerbated myocardial dysfunction, 30 and 60 days after MI compared to wild type (WT) mice as measured by echocardiogram. In addition, Peli1−/− mice also showed decreased motor function scores and perfusion ratios compared with Peli1fl/fl mice 28 days after the induction of HLI. The use of Peli1 in adenoviral gene therapy following HLI in CD1 mice improved the perfusion ratio at 28 days compared to Ad.LacZ-injected mice. These results suggest new insights into the protective role of Peli1 on ischemic tissues and its influence on survival signaling.

Personalized nutrition refers to the creation and delivery of dietary advice based on an individual’s unique set of intrinsic and extrinsic factors, meant to treat or prevent disease and develop eating behaviors that promote health. Thanks to the Human Genome Project as well as other historical advances in science and technology, it has become feasible to entertain the idea of truly personalized nutritional guidance. It is hoped that the implementation of such feedback will promote overall social health, and it is estimated that sometime in the near future more and more people will base food choices at least partly on their genetic, phenotypic and metabolic makeup, as well as external circumstances. This chapter seeks to provide an overview of personalized nutrition, starting at its inception and culminating with modern perspectives that delineate its importance as a possible therapeutic and preventative clinical tool in the 21st century.

Background Sepsis is a leading cause of mortality among patients in intensive care units across the USA. Thioredoxin-1 (Trx-1) is an essential 12 kDa cytosolic protein that, apart from maintaining the cellular redox state, possesses multifunctional properties. In this study, we explored the possibility of controlling adverse myocardial depression by overexpression of Trx-1 in a mouse model of severe sepsis. Methods Adult C57BL/6J and Trx-1Tg/+ mice were divided into wild-type sham (WTS), wild-type cecal ligation and puncture (WTCLP), Trx-1Tg/+sham (Trx-1Tg/+S), and Trx-1Tg/+CLP groups. Cardiac function was evaluated before surgery, 6 and 24 hours after CLP surgery. Immunohistochemical and Western blot analysis were performed after 24 hours in heart tissue sections. Results Echocardiography analysis showed preserved cardiac function in the Trx-1Tg/+ CLP group compared with the WTCLP group. Similarly, Western blot analysis revealed increased expression of Trx-1, heme oxygenase-1 (HO-1), survivin (an inhibitor of apoptosis [IAP] protein family), and decreased expression of thioredoxin-interacting protein (TXNIP), caspase-3, and 3- nitrotyrosine in the Trx-1Tg/+CLP group compared with the WTCLP group. Immunohistochemical analysis showed reduced 4-hydroxynonenal, apoptosis, and vascular leakage in the cardiac tissue of Trx-1Tg/+CLP mice compared with mice in the WTCLP group. Conclusions Our results indicate that overexpression of Trx-1 attenuates cardiac dysfunction during CLP. The mechanism of action may involve reduction of oxidative stress, apoptosis, and vascular permeability through activation of Trx-1/HO-1 and anti-apoptotic protein survivin.

Background There is keen interest in finding nonsurgical treatments for peripheral vascular disease (PVD). Previously, we demonstrated that selective activation of Thioredoxin1 (Trx1), a 12-kDa cytosolic protein, initiates redox-dependent signaling and promotes neovascularization after ischemic heart disease. Therefore, Trx1 might possess immense potential to not only treat murine hind limb ischemia (HLI) through effective angiogenesis but also provide PVD patients with nonsurgical therapy to enhance neovascularization and improve blood perfusion. Methods To determine whether activation of Trx1 increases blood perfusion in HLI, two different strategies were used—gene therapy and transgenic model system. In adenoviral-mediated gene therapy, 8- to 12-wk-old mice were divided into two groups: (1) control Adeno-LacZ (Ad-LacZ) and (2) Adeno-Thiroedoxin1 (Ad-Trx1). The mice underwent surgical intervention to induce right HLI followed by injection with Ad-LacZ or Ad-Trx1, respectively. In the second strategy, we used wild-type and transgenic mice overexpressing Trx1 (Trx1 Tg/+ ). All the animals underwent Doppler imaging for the assessment of limb perfusion followed by immunohistochemistry and Western blot analysis. Results Significant increases in perfusion ratio were observed in all the Trx1 overexpressed groups compared with their corresponding controls. Expressions of heme oxygenase-1, vascular endothelial growth factor, and the vascular endothelial growth factor receptors Flk-1 and Flt-1 were increased in Trx1 overexpressed mice compared with their respective controls. Blood perfusion in the ischemic limb gradually improved and significantly recovered in Trx1 Tg/+ and Ad-Trx1 groups compared with their corresponding controls. The capillary and arteriolar density in the ischemic zone were found to be higher in Trx1 Tg/+ group compared with wild type. Conclusions The overall outcomes of our study demonstrate that Trx1 enhances blood perfusion and increases angiogenic protein expression in a rodent HLI model. These results suggest that Trx1 is a potential target for clinical trials and drug therapy for the treatment of PVD.

The complete loss of dermal tissue due to ischemia is a serious challenge facing clinicians. Frequently, the failure of wound healing is due to ischemic conditions prevailing at the site of damaged tissue. Restoration of lost vasculature at the ischemic site can be achieved by supplementing proangiogenic stimuli through an engineered scaffold mimicking dermal extracellular matrix. Towards this objective, we have developed an electrospun scaffold loaded with the pro-angiogenic molecule resveratrol. The physical and chemical changes in the polymeric scaffold before and after loading of resveratrol were characterized using field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), coherence scanning interferometry (CSI) and X-ray diffraction (XRD). A sustained release of resveratrol from the scaffold was elucidated by UV-spectrophotometer analysis. The enhancement in cell-matrix interaction was studied using human umbilical vein endothelial cells (HUVECs) seeded on the scaffolds. The biocompatibility analysis of resveratrol loaded scaffolds was evaluated through a subcutaneous implantation study in mice. The therapeutic potential of resveratrol loaded scaffolds to accelerate tissue repair was analyzed in a full-thickness ischemic wound model in mice. Wound closure and H&E staining analysis showed rapid closure of ischemic wound area and re-epithelialization in resveratrol loaded scaffold treated groups compared to collagen and negative control groups. The immunostaining analysis further revealed the activation of thioredoxin-1 (Trx-1), heme oxygenase-1 (HO-1) mediated vascular endothelial growth factor (VEGF) signaling in resveratrol loaded scaffold treated group. The expression of Bcl-2 in healing wound edges post-treatment with resveratrol loaded scaffold confirmed the anti-apoptotic effect mediated by resveratrol. From this study, we explored a synergistic effect mediated by resveratrol and fibrous scaffolds to aid the ischemic wound healing process through effective vascularization.

Background Nonhealing wounds are a continuing health problem in the United States. Overproduction of reactive oxygen species is a major causative factor behind delayed wound healing. Previously we reported that thioredoxin-1 treatment could alleviate oxidative stress under ischemic conditions, such as myocardial infarction and hindlimb ischemia. In this study, we explored the potential for thioredoxin-1 gene therapy to effectively aid wound healing through improved angiogenesis in a murine ischemic wound model. Methods Full-thickness, cutaneous, ischemic wounds were created in the dorsum skin flap of 8- to 12-week-old CD1 mice. Nonischemic wounds created lateral to the ischemic skin flap served as internal controls. Mice with both ischemic wounds and nonischemic wounds were treated with Adeno-LacZ (1 × 109 pfu) or Adeno-thioredoxin-1 (1 × 109 pfu), injected intradermally around the wound. Digital imaging was performed on days 0, 3, 6, and 9 to assess the rate of wound closure. Tissue samples collected at predetermined time intervals were processed for immunohistochemical analysis. Results No significant differences in wound closure were identified among the nonischemic wounds control, nonischemic wounds-LacZ, and nonischemic wounds–thioredoxin-1 groups. Hence, only mice with ischemic wounds were further analyzed. The ischemic wounds–thioredoxin-1 group had significant improvement in wound closure on days 6 and 9 after surgery compared with the ischemic wounds control and ischemic wounds-LacZ groups. Immunohistochemical analysis indicated increased thioredoxin-1, vascular endothelial cell growth factor, and β-catenin levels in the ischemic wounds–thioredoxin-1 group compared with the ischemic wounds control and ischemic wounds-LacZ groups, as well as increased capillary density and cell proliferation, as represented by Ki-67 staining. Conclusion Taken together, thioredoxin-1 gene therapy promotes vascular endothelial cell growth factor signaling and re-epithelialization and activates wound closure in mice with ischemic wounds.

Introduction Engraftment of mesenchymal stem cells (MSCs) has emerged as a powerful candidate for mediating myocardial repair. In this study, we genetically modified MSCs with an adenovector encoding thioredoxin-1 (Ad.Trx1). Trx1 has been described as a growth regulator, a transcription factor regulator, a cofactor, and a powerful antioxidant. We explored whether engineered MSCs, when transplanted, are capable of improving cardiac function and angiogenesis in a rat model of myocardial infarction (MI). Methods Rat MSCs were cultured and divided into MSC, MSC+Ad.LacZ, and MSC+Ad.Trx1 groups. The cells were assayed for proliferation, and differentiation potential. In addition, rats were divided into control-sham (CS), control-MI (CMI), MSC+Ad.LacZ-MI (MLZMI), and MSC+Ad.Trx1-MI (MTrxMI) groups. MI was induced by left anterior descending coronary artery (LAD) ligation, and MSCs preconditioned with either Ad.LacZ or Ad.Trx1 were immediately administered to four sites in the peri-infarct zone. Results The MSC+Ad.Trx1 cells increased the proliferation capacity and maintained pluripotency, allowing them to divide into cardiomyocytes, smooth muscle, and endothelial cells. Western blot analysis, 4days after treatment showed increased vascular endothelial growth factor (VEGF), heme oxygenase-1 (HO-1), and C-X-C chemokine receptor type 4 (CXCR4). Also capillary density along with myocardial function as examined by echocardiography was found to be increased. Fibrosis was reduced in the MTrxMI group compared to MLZMI and CMI. Visualization of Connexin-43 by immunohistochemistry confirmed increased intercellular connections in the MTrxMI rats compared to MLZMI. Conclusion Engineering MSCs to express Trx1 may prove to be a strategic therapeutic modality in the treatment of cardiac failure.

Clinical studies of Phyllanthus emblica (P. emblica) have shown that it increases production of nitric oxide, glutathione, and high-density lipoprotein (HDL); decreases low-density lipoprotein (LDL), total cholesterol, triglycerides, and high-sensitivity C-reactive protein (hsCRP); and significantly inhibits platelet aggregation. The following study was designed to examine the effect of P. emblica treatment on myocardial ischemia-reperfusion (I/R) injury and identify the molecular targets and its underlying mechanism(s). Experimental animals were divided into four groups: control sham (CS), P. emblica sham (PS), control I/R (CIR), and P. emblica I/R (PIR). Rats in the P. emblica groups were gavaged with aqueous P. emblica solution (100 mg/kg body weight) for 30 days. After 30 days of gavaging, the I/R group underwent I/R surgery (45-min ischemia) followed by 4 or 30 days of reperfusion. Rats in the sham group underwent surgery without ligation. Left ventricular tissue samples, 4 and 30 days after I/R, were used for Western blot analysis and immunohistochemistry, respectively. Western blot analysis showed upregulation of phosphorylated Akt and GSK3-β and increased nuclear translocation of β-catenin in the PIR group versus CIR. PIR rats also indicated reduced 3-nitrotyrosine and Caspase-3 expression. Increased phosphorylation of endothelial nitric oxide synthase (p-eNOS) and upregulation of anti-apoptotic protein Bcl-2 were found in the PIR group. Echocardiography showed increased ejection fraction and fractional shortening and decreased left ventricular internal diameter in experimental subjects compared to controls. There was decreased fibrosis in P. emblica-treated rats compared to controls. The results of this study indicate that P. emblica is capable of upregulating the PI3K/Akt/GSK3β/β-catenin cardioprotective pathway, thereby preserving cardiac tissue during ischemia-reperfusion injury.

Objective— Neuropilin-1 (NRP-1) is a multidomain membrane receptor involved in angiogenesis and development of neuronal circuits, however, the role of NRP-1 in cardiovascular pathophysiology remains elusive. Approach and Results— In this study, we first observed that deletion of NRP-1 induced peroxisome proliferator–activated receptor γ coactivator 1α in cardiomyocytes and vascular smooth muscle cells, which was accompanied by dysregulated cardiac mitochondrial accumulation and induction of cardiac hypertrophy- and stress-related markers. To investigate the role of NRP-1 in vivo, we generated mice lacking Nrp-1 in cardiomyocytes and vascular smooth muscle cells (SM22-α- Nrp-1 KO), which exhibited decreased survival rates, developed cardiomyopathy, and aggravated ischemia-induced heart failure. Mechanistically, we found that NRP-1 specifically controls peroxisome proliferator–activated receptor γ coactivator 1 α and peroxisome proliferator–activated receptor γ in cardiomyocytes through crosstalk with Notch1 and Smad2 signaling pathways, respectively. Moreover, SM22-α- Nrp-1 KO mice exhibited impaired physical activities and altered metabolite levels in serum, liver, and adipose tissues, as demonstrated by global metabolic profiling analysis. Conclusions— Our findings provide new insights into the cardioprotective role of NRP-1 and its influence on global metabolism.

Background Statins (HMG-CoA reductase inhibitors), are known to improve cardiac function in diabetes-induced cardiovascular disease. We investigated the mechanism by which statins ameliorate cardiac function after myocardial infarction (MI). Simvastatin (S) increased tube formation and migration of HUVEC in vitro . We examined the role of simvastatin on cardiac function in streptozotocin (STZ) induced diabetic rats subjected to MI. Methods Rats were randomly assigned to 1) Control (non-diabetic) Sham (CS); 2) Control (non-diabetic) MI (CMI); 3) Control Statin treated Sham (CSS); 4) Control Statin treated MI (CSMI); 5) Diabetic Sham (DS); 6) Diabetic MI (DMI); 7) Diabetic Statin treated Sham (DSS); 8) Diabetic Statin treated MI (DSMI). Two weeks after STZ/saline injection Simvastatin (1mg/kg.b.wt) was gavaged for 15days (d). MI was induced 30 d after treatment by permanent LAD ligation. Results The S treated MI groups exhibited increased arteriolar density (23±0.6 vs. 14.8±0.4 counts/mm 2 , DSMI vs. DMI) and reduced fibrosis at 30d post-MI. VEGF measurement by ELISA after 4d post-MI showed increased expression in DSMI group compared to DMI group. Western blot analysis showed decreased Prolyl-4-Hydroxylase 3 (PHD-3) in DSMI group as compared to DMI group. Echocardiographic analysis 4weeks after post-MI showed significant improvement in ejection fraction (50.11±1.83 vs. 32.46±2.19%; DSMI vs. DMI) and fractional shortening (26.77±1.12 vs.16.36±1.22%; DSMI vs. DMI) in both statin-treated MI groups regardless of diabetic status. Conclusion These results suggest that statin therapy mitigates impairment of angiogenesis and myocardial dysfunction following MI in the diabetic rat through PHD3 inhibition.

We examined the effects of overexpressing HSPA12B on angiogenesis and myocardial function by intramyocardial administration of adenovirus encoding HSPA12B (Ad. HSPA12B) in a streptozotocin-induced diabetic rat subjected to myocardial infarction. Rats were divided randomly into six groups: control sham (CS) + Ad.LacZ, control myocardial infarction (CMI) + Ad.LacZ, control MI + Ad.HSPA12B, diabetic sham (DS) + Ad.LacZ, diabetic MI + Ad.LacZ and diabetic MI + Ad.HSPA12B. Following MI or sham surgery, the respective groups received either Ad.LacZ or Ad.HSPA12B via intramyocardial injections. We observed increased capillary and arteriolar density along with reduced fibrosis and preserved heart functions in DMI-AdHSPA12B compared to DMI-AdLacZ group. Western blot analysis demonstrated enhanced HSPA12B, vascular endothelial growth factor (VEGF), thioredoxin-1 (Trx-1) expression along with decreased expression of thioredoxin interacting protein (TXNIP) and A kinase anchoring protein 12 (AKAP12) in the DMI-AdHSPA12B compared to DMI-AdLacZ group. Our findings reveal that HSPA12B overexpression interacts with AKAP12 and downregulate TXNIP in diabetic rats following acute MI.

Reduced skin flap survival due to ischemia is a serious concern during reconstructive cosmetic surgery. The absence of VEGF and its receptors during ischemia may lead to flap failure. We identified Peli1, a 46-kDa protein, as a proangiogenic molecule and is directly regulated by VEGF. Therefore, we hypothesized that Peli1 acts downstream of Flk-1/VEGFR2 and aids in skin flap survival during ischemia.Scratch and matrigel assays were performed to observe cell proliferation, migration, and tube formation in vitro. Western blot analysis was carried out to detect the phosphorylation of Akt (p-Akt) and MAPKAPK2 (p-MK2) in HUVECs. The translational potential of Peli1 pretreatment in the rescue of skin flap tissue was studied in vivo using Flk-1Western blot analysis revealed a direct relationship between Peli1 and VEGF, as demonstrated by loss-of-function and gain-of-function studies. In addition, pretreatment with Ad.Peli1 restored the phosphorylation of Akt and MK2 and improved the migration potential of Flk-1-knockdown cells. Ad.Peli1 pretreatment salvaged the ischemic skin flap of Flk-1Our findings reveal that Peli1 is a proangiogenic molecule that acts downstream of VEGF-Flk-1 and restores angiogenesis and enhances skin flap survivability.

Hypoxia-inducible transcription factor (HIF)-prolyl hydroxylases domain (PHD-1–3) are oxygen sensors that regulate the stability of the HIFs in an oxygen-dependent manner. Suppression of PHD enzymes leads to stabilization of HIFs and offers a potential treatment option for many ischemic disorders, such as peripheral artery occlusive disease, myocardial infarction, and stroke. Here, we show that homozygous disruption of PHD-1 (PHD-1−/−) could facilitate HIF-1α-mediated cardioprotection in ischemia/reperfused (I/R) myocardium. Wild-type (WT) and PHD-1−/− mice were randomized into WT time-matched control (TMC), PHD-1−/− TMC (PHD1TMC), WT I/R, and PHD-1−/− I/R (PHD1IR). Isolated hearts from each group were subjected to 30 min of global ischemia followed by 2 h of reperfusion. TMC hearts were perfused for 2 h 30 min without ischemia. Decreased infarct size (35% ± 0.6% vs. 49% ± 0.4%) and apoptotic cardiomyocytes (106 ± 13 vs. 233 ± 21 counts/100 high-power field) were observed in PHD1IR compared to wild-type ischemia/reperfusion (WTIR). Protein expression of HIF-1α was significantly increased in PHD1IR compared to WTIR. mRNA expression of β-catenin (1.9-fold), endothelial nitric oxide synthase (1.9-fold), p65 (1.9-fold), and Bcl-2 (2.7-fold) were upregulated in the PHD1IR compared with WTIR, which was studied by real-time quantitative polymerase chain reaction. Further, gel-shift analysis showed increased DNA binding activity of HIF-1α and nuclear factor-kappaB in PHD1IR compared to WTIR. In addition, nuclear translocation of β-catenin was increased in PHD1IR compared with WTIR. These findings indicated that silencing of PHD-1 attenuates myocardial I/R injury probably by enhancing HIF-1α/β-catenin/endothelial nitric oxide synthase/nuclear factor-kappaB and Bcl-2 signaling pathway. Antioxid. Redox Signal. 15, 1789–1797.

Circumstantial evidence frequently implicates oxygen-derived free radicals and oxidative stress as mediators of myocardial ischemia/reperfusion (I/R) injury. Therefore, external supplementation of natural antioxidants plays a main role as cardioprotective compounds. This study was designed to evaluate the cardioprotective effect of VitaePro (70 mg/kg body weight, 21 days), a novel antioxidant mix of astaxanthin, lutein and zeaxanthin in a rat ex vivo model of ischemia/reperfusion injury. The cardioprotective effect of VitaePro was also compared with vitamin E (70 mg/kg body weight, 21 days) treatment. Rats were randomized into control I/R (CIR), VitaePro I/R (VPIR) and Vitamin E I/R (VEIR). After 21 days of oral treatment, isolated hearts from each group were subjected to 30 min of ischemia followed by 2 h of reperfusion. In the VPIR group compared to CIR and VEIR groups at 2 h of reperfusion, increased left ventricular functional recovery, such as left ventricular developed pressure (92.7 ± 0.7 vs. 85.3 ± 0.3 and 89.4 ± 1.2 mm Hg), dp/dt max (2518.7 ± 77.9 vs. 1962.5 ± 24 and 2255.7 ± 126.6 mm Hg/s), and aortic flow (21.5 ± 1.36 vs. 4.4 ± 0.6 and 13.2 ± 1.02 ml/min) were observed. The infarct size (27.68 ± 1.7 vs. 45.4 ± 1.8 and 35.4 ± 0.6%), apoptotic cardiomyocytes (61.7 ± 10.6 vs. 194.1 ± 14.8 and 118.7 ± 15.4 counts/100 HPF) and thiobarbituric acid reactive substances levels (80 ± 3 vs. 127 ± 5 and 103 ± 2 nM/mg tissue) also were decreased in VPIR group when compared to CIR and VEIR. As evidenced by the data, administration of vitamin E offered substantial cardioprotection to I/R injury, but VitaePro enhanced cardioprotection significantly more than vitamin E treatment. Taken in concert, the results of this study suggests that the oral ingestion of VitaePro protects myocardium from ischemia/reperfusion injury by decreasing oxidative stress and apoptosis, which may be of therapeutic benefit in the treatment of cardiovascular complications. However, further in vivo animal and human intervention studies are warranted before establishing any recommendations about usage of VitaePro for human cardiovascular complications.

Oxidative stress plays a crucial role in disruption of neovascularization by alterations in thioredoxin 1 (Trx1) expression and its interaction with other proteins after myocardial infarction (MI). We previously showed that Trx1 has angiogenic properties, but the possible therapeutic significance of overexpressing Trx1 in chronic MI has not been elucidated. Therefore, we explored the angiogenic and cardioprotective potential of Trx1 in an in vivo MI model using transgenic mice overexpressing Trx1. Wild-type (W) and Trx1 transgenic (Trx1(Tg/+)) mice were randomized into W sham (WS), Trx1(Tg/+) sham (TS), WMI, and TMI. MI was induced by permanent occlusion of LAD coronary artery. Hearts from mice overexpressing Trx1 exhibited reduced fibrosis and oxidative stress and attenuated cardiomyocyte apoptosis along with increased vessel formation compared to WMI. We found significant inhibition of Trx1 regulating proteins, TXNIP and AKAP 12, and increased p-Akt, p-eNOS, p-GSK-3β, HIF-1α, β-catenin, VEGF, Bcl-2, and survivin expression in TMI compared to WMI. Echocardiography performed 30days after MI revealed significant improvement in myocardial functions in TMI compared to WMI. Our study identifies a potential role for Trx1 overexpression and its association with its regulatory proteins TXNIP, AKAP12, and subsequent activation of Akt/GSK-3β/β-catenin/HIF-1α-mediated VEGF and eNOS expression in inducing angiogenesis and reduced ventricular remodeling. Hence, Trx1 and other proteins identified in our study may prove to be potential therapeutic targets in the treatment of ischemic heart disease.

Aldose reductase (AR) is a multifunctional enzyme that catalyzes the reduction of glucose and lipid peroxidation-derived aldehydes. During myocardial ischemia, the activity of AR is increased due to the oxidation of its cysteine residues to sulfenic acids. It is not known, however, whether the activated, sulfenic form of the protein (AR-SOH) is converted back to its reduced, unactivated state (AR-SH). We report here that in perfused mouse hearts activation of AR during 15 min of global ischemia is completely reversed by 30 min of reperfusion. During reperfusion, AR-SOH was converted to a mixed disulfide (AR-SSG). Deactivation of AR and the appearance of AR-SSG during reperfusion were delayed in hearts of mice lacking glutathione S-transferase P (GSTP). In vitro, GSTP accelerated glutathiolation and inactivation of AR-SOH. Reduction of AR-SSG to AR-SH was facilitated by glutaredoxin (GRX). Ischemic activation of AR was increased in GRX-null hearts but was attenuated in the hearts of cardiospecific GRX transgenic mice. Incubation of AR-SSG with GRX led to the regeneration of the reduced form of the enzyme. In ischemic cardiospecific AR transgenic hearts, AR was co-immunoprecipitated with GSTP, whereas in reperfused hearts, the association of AR with GRX was increased. These findings suggest that upon reperfusion of the ischemic heart AR-SOH is converted to AR-SSG via GSTP-assisted glutathiolation. AR-SSG is then reduced by GRX to AR-SH. Sequential catalysis by GSTP and GRX may be a general redox switching mechanism that regulates the reduction of protein sulfenic acids to cysteines.

Diabetes, one of the major risk factors of metabolic syndrome culminates in the development of Ischemic Heart Disease (IHD). Refined diets that lack micronutrients, mainly trivalent chromium (Cr3+) have been identified as the contributor in the rising incidence of diabetes. We investigated the effect of niacin-bound chromium (NBC) during ischemia/reperfusion (IR) injury in streptozotocin induced diabetic rats. Rats were randomized into: Control (Con); Diabetic (Dia) and Diabetic rats fed with NBC (Dia+NBC). After 30 days of treatment, the isolated hearts were subjected to 30 min of global ischemia followed by 2 h of reperfusion. NBC treatment demonstrated significant increase in left ventricular functions and significant reduction in infarct size and cardiomyocyte apoptosis in Dia+NBC compared with Dia. Increased Glut-4 translocation to the lipid raft fractions was also observed in Dia+NBC compared to Dia. Reduced Cav-1 and increased Cav-3 expression along with phosphorylation of Akt, eNOS and AMPK might have resulted in increased Glut-4 translocation in Dia+NBC. Our results indicate that the cardioprotective effect of NBC is mediated by increased activation of AMPK, Akt and eNOS resulting in increased translocation of Glut-4 to the caveolar raft fractions thereby alleviating the effects of IR injury in the diabetic myocardium.

Sildenafil citrate (SC), a drug for erectile dysfunction, is now emerging as a cardiopulmonary drug. Our study aimed to determine a novel role of sildenafil on cardioprotection through stimulating angiogenesis during ischaemia (I) reperfusion (R) at both capillary and arteriolar levels and to examine the role of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1) in this mechanistic effect. Rats were divided into: control sham (CS), sildenafil sham (SS), control + IR (CIR) and sildenafil + IR (SIR). Rats were given 0.7 mg/kg, (i.v) of SC or saline 30 min. before occlusion of left anterior descending artery followed by reperfusion (R). Sildenafil treatment increased capillary and arteriolar density followed by increased blood flow (2-fold) compared to control. Treatment with sildenafil demonstrated increased VEGF and Ang-1 mRNA after early reperfusion. PCR data were validated by Western blot analysis. Significant reduction in infarct size, cardiomyocyte and endothelial apoptosis were observed in SC-treated rats. Increased phosphorylation of Akt, eNOS and expression of anti-apoptotic protein Bcl-2, and thioredoxin, hemeoxygenase-1 were observed in SC-treated rats. Echocardiography demonstrated increased fractional shortening and ejection fraction following 45 days of reperfusion in the treatment group. Stress testing with dobutamine infusion and echocardiogram revealed increased contractile reserve in the treatment group. Our study demonstrated for the first time a strong additional therapeutic potential of sildenafil by up-regulating VEGF and Ang-1 system, probably by stimulating a cascade of events leading to neovascularization and conferring myocardial protection in in vivo I/R rat model.

Bromelain (Br), a proteolytic enzyme extracted from the stem of the pineapple, is known to possess anti-inflammatory activity and has been shown to reduce blood viscosity, prevent the aggregation of blood platelets, and improve ischemia-reperfusion (I/R) injury in a skeletal muscle model. We investigated the capacity of Br to limit myocardial injury in a global I/R model. Adult male Sprague-Dawley rats were divided into two groups: control (PBS) and Br at 10 mg/kg in PBS administered via intraperitoneal injection (twice/day) for 15 consecutive days. On day 16, the hearts were excised and subjected to 30 min of global ischemia followed by 2 h of reperfusion. Br treatment showed higher left ventricular functional recovery throughout reperfusion compared with the controls [maximum rate of rise in intraventricular pressure (dP/d tmax), 2,225 vs. 1,578 mmHg/s at 2 h reperfusion]. Aortic flow was also found to be increased in Br treatment when compared with that in untreated rats (11 vs. 1 ml). Furthermore, Br treatment reduced both the infarct size (34% vs. 43%) and the degree of apoptosis (28% vs. 37%) compared with the control animals. Western blot analysis showed an increased phosphorylation of both Akt and FOXO3A in the treatment group compared with the control. These results demonstrated for the first time that Br triggers an Akt-dependent survival pathway in the heart, revealing a novel mechanism of cardioprotective action and a potential therapeutic target against I/R injury.

This study addresses an important clinical issue by identifying potential candidates of vascular endothelial growth factor (VEGF) signalling through the Flk-1 receptor that trigger cardioprotective signals under ischaemic stress. Isolated working mouse hearts of both wild-type (WT) and Flk-1(+/-) were subjected to global ischaemia (I) for 30 min. followed by 2 hrs of reperfusion (R). Flk-1(+/-) myocardium displayed almost 50% reduction in Flk-1 mRNA as examined by quantitative real-time RT-PCR at the baseline level. Flk-1(+/-) mouse hearts displayed reduction in left ventricular functional recovery throughout reperfusion (dp/dt 605 versus 884), after 2 hrs (P0.05). Coronary (1.9 versus 2.4 ml) and aortic flow (AF) (0.16 versus 1.2 ml) were reduced in Flk-1(+/-) after 2 hrs of reperfusion. In addition, increased infarct size (38.4%versus 28.41%, P0.05) and apoptotic cardiomyocytes (495 versus 213) were observed in Flk-1(+/-) knockout (KO) mice. We also examined whether ischaemic preconditioning (PC), a novel method to induce cardioprotection against ischaemia reperfusion injury, through stimulating the VEGF signalling pathway might function in Flk-1(+/-) mice. We found that knocking down Flk-1 resulted in significant reduction in the cardioprotective effect by PC compared to WT. Affymetrix gene chip analysis demonstrated down-regulation of important genes after IR and preconditioning followed by ischaemia reperfusion in Flk-1(+/-) mice compared to WT. To get insight into the underlying molecular pathways involved in ischaemic PC, we determined the distinct and overlapping biological processes using Ingenuity pathway analysis tool. Independent evidence at the mRNA level supporting the Affymetrix results were validated using real-time RT-PCR for selected down-regulated genes, which are thought to play important roles in cardioprotection after ischaemic insult. In summary, our data indicated for the first time that ischaemic PC modifies genomic responses in heterozygous VEGFR-2/Flk-1 KO mice and abolishes its cardioprotective effect on ischaemic myocardium.

Despite significant advances in myocardial revascularization and reperfusion, coronary artery disease and subsequently myocardial infarction, are the leading cause of morbidity and mortality in the US. Thus one of the main goals in the treatment of myocardial ischemia is the development of effective therapy for angiogenesis. The first evidence is the demonstration of alleviation of myocardial ischemia and increased number of collateral blood vessels in the early 1990s following intra-coronary administration of basic fibroblast growth factor protein in dog. Multiple animal studies, has confirmed the concept of stimulation of collateral development by pharmacological and molecular means. This includes direct delivery of growth factors into the ischemic target tissues, or of genes that encode for synthesis of growth factors by target tissues. Both cell therapy and gene therapy have proven to be effective to promote neovascularization in various animal models. Cell therapy alone is proven to be beneficial however the combination of cell and gene therapy (growth factors) may enhance therapeutic neovascularization. Thus clinically relevant, combined strategy could be an excellent strategy for treating patients with myocardial infarction.

This report demonstrates that mice deficient in Flt-1 failed to establish ischemic preconditioning (PC)-mediated cardioprotection in isolated working buffer-perfused ischemic/reperfused (I/R) hearts compared to wild type (WT) subjected to the same PC protocol. WT and Flt-1+/- mice were divided into four groups: (1) WT I/R, (2) WT + PC, (3) Flt-1+/- I/R, and (4) Flt-1+/- + PC. Group 1 and 3 mice were subjected to 30 min of ischemia followed by 2 h of reperfusion and group 2 and 4 mice were subjected to four episodes of 4-min global ischemia followed by 6 min of reperfusion before ischemia/reperfusion. For both wild-type and Flt-1+/- mice, the postischemic functional recovery for the hearts was lower than the baseline, but the recovery for the knockout mice was less compared to the WT mice even in preconditioning. The myocardial infarction and apoptosis were higher in Flt-1+/- compared to wild-type I/R. Flt-1+/- KO mice demonstrated pronounced inhibition of the expression of iNOS, p-AKT & p-eNOS. Significant inhibition of STAT3 & CREB were also observed along with the inhibition of HO-1 mRNA. Results demonstrate that Flt-1+/- mouse hearts are more susceptible to ischemia/reperfusion injury and also document that preconditioning is not as effective as found in WT and therefore suggest the importance of VEGF/Flt-1 signaling in ischemic/reperfused myocardium.

Hypercholesterolemia (HC) is a common health problem that significantly increases risk of cardiovascular disease. Both statin (S) and resveratrol (R) demonstrated cardioprotection through nitric oxide-dependent mechanism. Therefore, the present study was undertaken to determine whether combination therapy with statin and resveratrol is more cardioprotective than individual treatment groups in ischemic rat heart model. The rats were fed with 2% high cholesterol diet and after 8 weeks of high cholesterol diet the animals were treated with statin (1 mg/kg bw/day) and resveratrol (20 mg/kg bw/day) for 2 weeks. The rats were assigned to: (1) Control (C), (2) HC, (3) HCR, (4) HCS and (5) HCRS. The hearts, subjected to 30-min global ischemia followed by 120-min reperfusion were used as experimental model. The left ventricular functional recovery (+dp/dt(max)) was found to be significantly better in the HCRS (1926+/-43), HCR (1556+/-65) and HCS (1635+/-40) compared to HC group (1127+/-16). The infarct sizes in the HCRS, HCS and HCR groups were 37+/-3.6, 43+/-3.3 and 44+/-4.2 respectively compared to 53+/-4.6 in HC. The lipid level was found to be decreased in all the treatment groups when compared to HC more significantly in HCS and HCRS groups when compared to HCR. Increased phosphorylation of Akt and eNOS was also observed in all the treatment groups resulting in decreased extent of cardiomyocyte apoptosis but the extent of reduction in apoptosis was more significant in HCRS group compared to all other groups. In vivo rat myocardial infarction (MI) model subjected to 1 week of permanent left descending coronary artery (LAD) occlusion documented increased capillary density in HCR and HCRS treated group when compared to HCS treatment group. We also documented increased beta-catenin translocation and increased VEGF mRNA expression in all treatment groups. Thus, we conclude that the acute as well as chronic protection afforded by combination treatment with statin and resveratrol may be due to pro-angiogenic, anti-hyperlipidemic and anti-apoptotic effects and long-term effects may be caused by increased neo-vascularization of the MI zone leading to less ventricular remodeling.

The reactive oxygen species (ROS) and reactive nitrogen species (RNS) generated from the enzymatic and nonenzymatic sources from superoxide (O2∙−) and nitric oxide (NO), respectively, are established to cause oxidative, nitroxidative, nitrative, and nitrosative stresses in the biological systems. Scientific evidence is mounting in favor of the involvement of ROS-induced oxidative stress and RNS stress in diverse pathophysiological states in experimental animal models and humans including the cardiovascular, cerebrovascular, and renal diseases to name a few. Among many proposed and tested theories of aging, the oxidative stress theory of aging underscores the ROS-induced damage as being instrumental in the progressive and unalterable alterations at the molecular, cellular, and organ levels during aging and shortening of life span. The balance between the ROS/RNS and antioxidants is highly critical to maintain the cellular health and any alteration in that balance caused by either the elevation of production of ROS/RNS or decrease of antioxidant status in the cells will lead to diverse pathophysiological states. Antioxidants (enzymatic and nonenzymatic), either endogenous or exogenous, are known to counteract the deleterious actions of ROS/RNS leading to protection against the oxidative stress and RNS stress. Therefore, this special issue focuses on the possibilities of protection against the ROS-induced oxidative stress and RNS stress which could potentially impact aging, life span, and diseases among humans. Several experts in the fields of ROS and RNS biology have contributed original research and review articles highlighting the state-of-the-art cellular and molecular mechanisms and protection of pathophysiology of oxidative stress and RNS stress in diseases, aging, and age-associated pathophysiological states.

Therapeutic angiogenesis represents a novel approach for the prevention and treatment of ischemic heart disease. This study examined a novel method of stimulating myocardial angiogenesis using secoisolariciresinol diglucoside (SDG), a plant lignan isolated from flaxseed. SDG has been shown to decrease serum cholesterol and reduce the extent of atherosclerosis. In the present study, the angiogenic properties of SDG were investigated in three different models. First, in the in vitro model, human coronary arteriolar endothelial cells (HCAEC) treated with SDG (50 and 100 microM) showed a significant increase in tubular morphogenesis compared with control. Western blot analysis indicated an increased expression of vascular endothelial growth factor (VEGF), kinase insert domain-containing receptor (KDR), Flt-1, angiopoietin-1 (Ang-1), Tie-1, and phosphorylated endothelial nitric oxide synthase (p-eNOS) in the SDG-treated cells. Second, in the ex vivo ischemia/reperfusion model, SDG-treated rats (20 mg/kg b.wt./day for 2 weeks orally) showed an increased level of aortic flow and functional recovery after 2 h of reperfusion following 30 min of ischemia compared with the control group [dP/dt (mm Hg/s) of 2110 +/- 35 versus 1752 +/- 62]. SDG reduced infarct size compared with the control group by 32% (38 versus 26%) and also decreased cardiomyocyte apoptosis. Increased protein expression of VEGF, Ang-1, and p-eNOS was also observed in the SDG-treated group. Third, in the in vivo myocardial infarction model, SDG increased capillary density and myocardial function as evidenced by increased fractional shortening and ejection fraction. In conclusion, these results suggest that SDG has potent angiogenic and antiapoptotic properties that may contribute to its cardioprotective effect in ischemic models.

This study was undertaken to investigate the effect of phosphodiesterase-5 (PDE5) inhibitor, sildenafil, on angiogenic response in human coronary arteriolar endothelial cells (HCAEC). The cells exposed to sildenafil (1-20 microM) demonstrated significantly accelerated tubular morphogenesis with the induction of thioredoxin-1 (Trx-1), hemeoxygenase-1 (HO-1) and VEGF. Sildenafil induced VEGF and angiopoietin specific receptors such as KDR, Tie-1 and Tie-2. This angiogenic response was repressed by tinprotoporphyrin IX (SnPP), an inhibitor of HO-1 enzyme activity. Sildenafil below 1 muM has no angiogenic effect as evidenced by reduced tuborogenesis. Sildenafil along with SnPP inhibited both VEGF and Angiopoietin-1 (Ang-1) protein expression. Therefore our results demonstrated for the first time that sildenafil is a very potent pro-angiogenic factor.

Objective Reduced skin flap survival due to ischemia is a serious concern during reconstructive cosmetic surgery. The absence of VEGF and its receptors during ischemia may lead to flap failure. We identified Peli1, a 46-kDa protein, as a proangiogenic molecule and is directly regulated by VEGF. Therefore, we hypothesized that Peli1 acts downstream of Flk-1/VEGFR2 and aids in skin flap survival during ischemia. Methods Scratch and matrigel assays were performed to observe cell proliferation, migration, and tube formation in vitro. Western blot analysis was carried out to detect the phosphorylation of Akt (p-Akt) and MAPKAPK2 (p-MK2) in HUVECs. The translational potential of Peli1 pretreatment in the rescue of skin flap tissue was studied in vivo using Flk-1+/− mice. Animals underwent dorsal ischemic skin flap surgery, and the tissue was collected on day 12 for analysis. Results Western blot analysis revealed a direct relationship between Peli1 and VEGF, as demonstrated by loss-of-function and gain-of-function studies. In addition, pretreatment with Ad.Peli1 restored the phosphorylation of Akt and MK2 and improved the migration potential of Flk-1-knockdown cells. Ad.Peli1 pretreatment salvaged the ischemic skin flap of Flk-1+/− mice by increasing blood perfusion and reducing the inflammatory response and the extent of necrosis. Conclusion Our findings reveal that Peli1 is a proangiogenic molecule that acts downstream of VEGF-Flk-1 and restores angiogenesis and enhances skin flap survivability.

Background: Our earlier studies showed that AKAP12 and Thioredoxin-Interacting Protein (TXNIP) interfere with HSPA12B-induced angiogenic signaling in rat myocardium. HSPA12B appears to play an essential role in myocardial angiogenesis, which is impaired during diabetes. This study explores the impact of HSPA12B overexpression on heart function, neovascularization, and downstream target proteins, AKAP12, Thioredoxin-1 (Trx-1) and VEGF, in non-diabetic and diabetic animals following myocardial infarction (MI). Methods: Rats were divided into 6 groups: 1) Non-Diabetic Sham (NDS), 2) Non-Diabetic LacZ MI (NDLZMI), 3) Non-Diabetic HSPA12B MI (NDHSPMI), 4) Diabetic Sham (DS), 5) Diabetic LacZ MI (DLZMI), 6) Diabetic HSPA12B MI (DHSPMI). Ad.LacZ/Ad.HSPA12B was administered intramyocardially at 4 sites around the infarct border zone in NDLZMI/DiaLZMI or NDHSPMI/DiaHSPMI animals immediately after permanent LAD ligation. Results: Co-immunoprecipitation followed by immunoblot analysis showed significant increase in HSPA12B/AKAP12 association in diabetic group suggesting that diabetes impairs HSPA12B availability triggering impairment of angiogenesis. This result was also confirmed by docking analysis (insilico models). Trx-1 activity (1.73 fold) along with HSPA12B and VEGF expression was increased in DHSPMI and NDHSPMI compared to respective controls. Both AKAP12 (1.31 fold) and TXNIP (2.22 fold) appeared to be down-regulated in HSPA12B-treated groups compared to controls. Echocardiography demonstrated increased fractional shortening and ejection fraction 4 weeks post-MI in DHSPMI-treated rats compared to DLZMI. Increased capillary and arteriolar density in DHSPMI compared to DLZMI was obesrved by morphometric analysis. In addition Picrosirius red staining documented decreased fibrosis in DHSPMI vs. DLZMI myocardium. Conclusion: Therefore overexpression of HSPA12B enhances neovascularization and cardiac function following MI in diabetic animals by down-regulating Trx-1/TXNIP and HSPA12B/AKAP12 association, resulting in increased HSPA12B, Trx-1 and VEGF. These findings support a role for HSPA12B gene therapy in mitigating the morbid expression of ischemic heart disease in the setting of diabetes.

Introduction: Our present study attempted to evaluate the effect of Pellino1 (Peli1) overexpression on angiogenesis and myocardial function by intramyocardial administration of adenovirus encoding Peli1 (Ad.Peli1) following myocardial infarction (MI) in mice. Methods: CD-1/ICR mice were divided into six groups: Control Sham (CS); Control MI (CMI); Adeno-LacZ Sham (Ad.LacZS); Adeno-LacZ MI (Ad.LacZMI); Adeno-Pellino1 Sham (Ad.Peli1S) and Adeno-Pellino1 MI (Ad.Peli1MI). MI was induced by permanent ligation of left anterior descending coronary artery (LAD). Following LAD ligation or sham surgery Ad.LacZ or Ad.Peli1 was injected at 4 border zone sites to either Ad.LacZS/Ad.LaczMI or Ad.Peli1S/Ad.Peli1MI groups respectively. Heart tissue was collected 24 hours post MI for Western blot analysis,4 days for gap junction protein and 30 days later for immunohistochemistry after echocardiographic analysis. Results: Echocardiographic analysis revealed increased ejection fraction [48±0.75 vs. 33±0.98% (n=10-11);p Conclusion: Taken together, these data shows the potential of Peli1 gene therapy in inducing angiogenesis and reducing ventricular remodeling in the infarcted myocardium.

Introduction: Peripheral artery disease affects 12-20% Americans over the age of 60. Thioredoxin-1 (Trx-1) is a class of small redox proteins. We have demonstrated earlier that Trx-1 reduces oxidative stress resulting in less inflammation and increased angiogenesis in cardiac muscle via heme oxygenase-1 (HO-1) and VEGF after myocardial infarction. In the current study, we evaluate the effect of Trx-1 on post-ischemic hindlimb recovery. Methods: Peripheral artery disease was mimicked using a hindlimb ischemia (HLI) model. Wild type (WT) and Trx-1 transgenic (Trx-1Tg/+) mice (8-12 weeks old) were subjected to femoral artery ligation. Following surgery, mice were observed for 5 weeks. Serial laser doppler images were obtained, and perfusion ratios between the ischemic and non-ischemic limbs were calculated at set time intervals. The perfusion ratios were compared between WT and Trx-1Tg/+ groups. Immunohistochemical analysis of the skeletal muscle was performed to quantify the extent of fibrosis, capillary and arteriolar density 35 days after surgery. In addition, another set of experiments was designed with Ad.Trx-1 gene therapy after femoral artery ligation to study the molecular mechanism of neovascularization with Trx-1. Results: The recovery of hind limb perfusion was significantly increased in Trx-1Tg/+ mice at day 7 (0.19 ± 0.03 vs. 0.36 ± 0.07 (n=12-9), day-21 (0.37 ± 0.05 vs. 0.62 ± 0.03 (n=12-9), and day 28 (0.40 ± 0.04 vs. 0.79 ± 0.04 (n=10-9); p Conclusions: Our results suggest that Trx-1 is a potential therapeutic agent to increase blood perfusion and angiogenesis for the treatment of critical limb ischemia patients.