Effects of daidzein on rat ovary against ischemia-reperfusion.

PURPOSE: Our aim was to investigate protective effects of daidzein treatment on ischemia-reperfusion (I/R) injury-induced ovarian tissue by immunohistochemical techniques. METHODS: Thirty Sprague Dawley female rats were categorized into three groups as sham, I/R group, and I/R+daidzein groups. Bloods were analyzed for malondialdehyde (MDA), glutathione peroxidase (GSH), and myeloperoxidase (MPO), and ovaries were processed for histological tissue protocol. RESULTS: Both MDA and MPO values were increased in I/R group compared to sham and I/R+daidzein groups. GSH content was increased in I/R+daidzein group compared to I/R groups. In I/R group, theca and follicular cells were degenerated with apoptosis and dilatation and congestion, edema. In I/R+daidzein group, daidzein improved pathologies. In the I/R group, Bax expression was positive with follicular cells, granulosa cells and inflammatory cells. In the I/R+daidzein group, positive Bax reaction was observed in the epithelial, antral, and inflammatory cells. In I/R group, Bcl-2 reaction was in germinative epithelial cells, cells of antral follicle. In the I/R+daidzein group, Bcl-2 expression level was reduced after daidzein treatment. CONCLUSIONS: After the I/R procedure, ovarian cells and follicles were degenerated with apoptosis and inflammation. After daidzein treatment, Bax and Bcl-2 signal were decreased. It was observed that daidzein stopped the apoptotic process.

Does fasting protect liver from ischemia and reperfusion injury?

PURPOSE: To evaluate local and systemic effects of 24-hour fasting in liver ischemia and reperfusion injury. METHODS: Twenty-one adult male Wistar rats (330-390 g) were submitted to 60 minutes of hepatic ischemia followed by 24 hours of reperfusion. Before the day of the experiment, the animals fasted, but free access to water was allowed. Two groups were constituted: Control: non-fasted, that is, feeding ad libitum before surgical procedure; Fasting: rats underwent previous fasting of 24 hours. Hepatic ischemia was performed using vascular clamp in hepatic pedicle. At 24 hours after liver reperfusion, blood and tissue samples were collected. To analysis, liver lobes submitted to ischemia was identified as ischemic liver and paracaval non-ischemic lobes as non-ischemic liver. We evaluated: malondialdehyde levels, hepatocellular function (alanine aminotransferase, aspartate aminotransferase activities, and both ratio), cytokines (interleukins-6, -10, and tumor necrosis factor-alpha), hepatic ischemia and reperfusion injury (histology). RESULTS: Malondialdehyde measured in non-ischemic and ischemic liver samples, hepatocellular function and cytokines were comparable between groups. Histological findings were distinct in three regions evaluated. Microvesicular steatosis was comparable between 24-hour fasting and non-fasted control groups in periportal region of hepatic lobe. In contrast, steatosis was more pronounced in zones 2 and 3 of ischemic liver samples of fasting compared to control groups. CONCLUSIONS: These data indicates that fasting does not protect, but it can be also detrimental to liver submitted to ischemia/reperfusion damage. At that time, using long fasting before liver surgery in the real world may be contraindicated.

Myocardial tissue microstructure with and without stress-induced ischemia assessed by T1 mapping in patients with stable coronary artery disease.

BACKGROUND: Stress-induced myocardial ischemia seems not to be associated with cardiovascular events. However, its effects on myocardial tissue characteristics remain under debate. Thus, we sought to assess whether documented stress-induced ischemia is associated with changes in myocardial microstructure evaluated by magnetic resonance native T1 map and extracellular volume fraction (ECV). METHODS: This is a single-center, analysis of the previously published MASS V Trial. Multivessel patients with a formal indication for myocardial revascularization and with documented stress-induced ischemia were included in this study. Native T1 and ECV values evaluated by cardiac magnetic resonance imaging of ischemic and nonischemic myocardial segments at rest and after stress were compared. Myocardial ischemia was detected by either nuclear scintigraphy or stress magnetic cardiac resonance protocol. RESULTS: Between May 2012 and March 2014, 326 prospective patients were eligible for isolated CABG or PCI and 219 were included in the MASS V trial. All patients underwent resting cardiac magnetic resonance imaging. Of a total of 840 myocardial segments, 654 were nonischemic segments and 186 were ischemic segments. Native T1 and ECV values of ischemic segments were not significantly different from nonischemic segments, both at rest and after stress induction. In addition, native T1 and ECV values of myocardial segments supplied by vessels with obstructive lesions were similar to those supplied by nonobstructive ones. CONCLUSION AND RELEVANCE: In this study, cardiac magnetic resonance identified similar T1 mapping values between ischemic and nonischemic myocardial segments. This finding suggests integrity and stability of myocardial tissue in the presence of stress-induced ischemia.

The effects of metyrosine on ischemia-reperfusion-induced oxidative ovarian injury in rats: Biochemical and histopathological assessment.

The aim of this study is to investigate the effect of metyrosine on ischemia-reperfusion (I/R) induced ovarian injury in rats in terms of biochemistry and histopathology. Rats were divided into: ovarian I/R (OIR), ovarian I/R+50 mg/kg metyrosine (OIRM) and sham (SG) operations. OIRM group received 50 mg/kg metyrosine one hour before the application of the anesthetic agent, OIR and SG group rats received equal amount of distilled water to be used as a solvent orally through cannula. Following the application of the anesthetic agent, ovaries of OIRM and OIR group rats were subjected to ischemia and reperfusion, each of which took two hours. This biochemical experiment findings revealed high levels of malondialdehyde (MDA) and cyclo-oxygenase-2 (COX-2) and low levels of total glutathione (tGSH), superoxide dismutase (SOD) and cyclo-oxygenase-1 (COX-1) in the ovarian tissue of OIR group, with significant histopathological injury. In metyrosine group, MDA and COX-2 levels were lower than the OIR group whereas tGSH, SOD and COX-1 levels were higher, with slighter histopathological injury. Our experimental findings indicate that metyrosine inhibits oxidative and pro-inflammatory damage associated with ovarian I/R in rats. These findings suggest that metyrosine could be useful in the treatment of ovarian injury associated with I/R.

Pre-treatment of the beta3-adrenergic receptor agonist BRL37344 reduces in vivo myocardial ischemia/reperfusion injury by improving AMPK and SIRT1 activity and by suppressing mTOR and p70S6K signaling pathways

Abstract This study aimed to investigate the role and signaling pathways of β3-AR in myocardial ischemia/reperfusion (I/R) injury, which is one of the leading causes of death worldwide. 47 male rats were randomly divided into two main groups to evaluate infarct size and molecular parameters. Rats in both groups were randomly divided into 4 groups. Control (sham), I/R (30 min ischemia/120 min reperfusion), BRL37344 (BRL) (A) (5 µg/kg single-dose pre-treatment (preT) before I/R) and BRL (B) (5 µg/kg/day preT for 10 days before I/R). Infarct size was determined with triphenyltetrazolium chloride staining and analyzed with ImageJ program. The levels of AMPK, SIRT1, mTOR, and p70SK6 responsible for cellular energy and autophagy were evaluated by western blot. Infarct size increased in the I/R group (44.84 ± 1.47%) and reduced in the single-dose and 10-day BRL-treated groups (32.22 ± 1.57%, 29.65 ± 0.55%; respectively). AMPK and SIRT1 levels were decreased by I/R but improved in the treatment groups. While mTOR and p70S6K levels increased in the I/R group, they decreased with BRL preT. BRL preT protects the heart against I/R injury. These beneficial effects are mediated in part by activation of AMPK and SIRT1, inhibition of mTOR and p70S6K, and consequently protected autophagy.

Effect of melatonin on electrical impedance and biomarkers of damage in a gastric ischemia/reperfusion model.

The damage to the gastrointestinal mucosa induced by ischemia/reperfusion (I/R) is closely related to high mortality in critically ill patients, which is attributable, in part, to the lack of an early method of diagnosis to show the degree of ischemia-induced injury in this type of patients. Electrical Impedance Spectroscopy (EIS) has been shown to be a tool to early diagnose gastric mucosal damage induced by ischemia. A therapeutic alternative to reduce this type of injury is melatonin (MT), which has gastroprotective effects in I/R models. In this work, the effect of treatment with MT on the electrical properties of gastric tissue, biomarkers of inflammatory (iNOS and COX-2), proliferation, and apoptotic process under I/R conditions in male Wistar rats was evaluated through EIS, histological and immunohistochemical analysis. Treatment with MT prevents gastric mucosa damage, causing a decrease in gastric impedance parameters related to the inflammatory process and cellular damage. This suggests that EIS could be used as a tool to diagnose and monitor the evolution of gastric mucosal injury, as well as in the recovery process in critically ill patients.

Therapeutic hypothermia for the treatment of neonatal hypoxia-ischemia: sex-dependent modulation of reactive astrogliosis.

Therapeutic hypothermia (TH) is the standard treatment for neonatal hypoxia-ischemia (HI) with a time window limited up to 6 h post injury. However, influence of sexual dimorphism in the therapeutic window for TH has not yet been elucidated in animal models of HI. Therefore, the aim of this study was to investigate the most effective time window to start TH in male and female rats submitted to neonatal HI. Wistar rats (P7) were divided into the following groups: NAÏVE and SHAM (control groups), HI (submitted to HI) and TH (submitted to HI and TH; 32ºC for 5 h). TH was started at 2 h (TH-2 h group), 4 h (TH-4 h group), or 6 h (TH-6 h group) after HI. At P14, animals were subjected to behavioural tests, volume of lesion and reactive astrogliosis assessments. Male and female rats from the TH-2 h group showed reduction in the latency of behavioral tests, and decrease in volume of lesion and intensity of GFAP immunofluorescence. TH-2 h females also showed reduction of degenerative cells and morphological changes in astrocytes. Interestingly, females from the TH-6 h group showed an increase in volume of lesion and in number of degenerative hippocampal cells, associated with worse behavioral performance. Together, these results indicate that TH neuroprotection is time- and sex-dependent. Moreover, TH started later (6 h) can worsen volume of brain lesion in females. These data indicate the need to develop specific therapeutic protocols for each sex and reinforce the importance of early onset of the hypothermic treatment.

A ketogenic diet attenuates acute and chronic ischemic kidney injury and reduces markers of oxidative stress and inflammation.

BACKGROUND: Ischemic kidney injury is a common clinical condition resulting from transient interruption of the kidney's normal blood flow, leading to oxidative stress, inflammation, and kidney dysfunction. The ketogenic diet (KD), a low-carbohydrate, high-fat diet that stimulates endogenous ketone body production, has potent antioxidant and anti-inflammatory effects in distinct tissues and might thus protect the kidney against ischemia and reperfusion (IR) injury. MAIN METHODS: Male Wistar rats were fed a KD or a control diet (CD) for three days before analyzing metabolic parameters or testing nephroprotection. We used two different models of kidney IR injury and conducted biochemical, histological, and Western blot analyses at 24 h and two weeks after surgery. KEY FINDINGS: Acute KD feeding caused protein acetylation, liver AMPK activation, and increased resistance to IR-induced kidney injury. At 24 h after IR, rats on KD presented reduced tubular damage and improved kidney functioning compared to rats fed with a CD. KD attenuated oxidative damage (protein nitration, 4-HNE adducts, and 8-OHdG), increased antioxidant defenses (GPx and SOD activity), and reduced inflammatory intermediates (IL6, TNFα, MCP1), p50 NF-κB expression, and cellular infiltration. Also, KD prevented interstitial fibrosis development at two weeks, up-regulation of HSP70, and chronic Klotho deficiency. SIGNIFICANCE: Our findings demonstrate for the first time that short-term KD increases tolerance to experimental kidney ischemia, opening the opportunity for future therapeutic exploration of a dietary preconditioning strategy to convey kidney protection in the clinic.

The effects of methanol extract of Galium verum L on cardiac redox state in hypertensive rats

Abstract The aim of this study was to assess the effects of methanol extract of G. verum on redox status of isolated heart of spontaneously hypertensive rats after ischemia. Twenty-four Wistar albino rats were divided into three groups: untreated control rats and rats that received 125 and 250 mg/kg G. verum extract for 4 weeks per os. Index of lipid peroxidation (measured as TBARS) and parameters of antioxidative defence system such as level of reduced glutathione (GSH) and activities of catalase (CAT) and superoxide dismutase (SOD) were spectrophotometrically determined in heart homogenate. The index of lipid peroxidation in heart tissue was lower in both treated groups compared to the control group. On the other hand, the activity of SOD was significantly higher after consumption of both doses, while the activity of CAT was significantly higher only after treatment with a higher dose of extract. Based on our results we might conclude that 4-week treatment with methanol extracts of G. verum has the potential to modulate myocardial redox signaling after ischemia, thus significantly alleviating cardiac oxidative stress and exerting dose-dependent antioxidant properties. Future studies are certainly necessary to fully clarify the role of this plant species in myocardial I-R injury.

A new combination of naringin and trimetazidine protect kidney Mitochondria dysfunction induced by renal Ischemia / Reperfusion injury in rat

Abstract Ischemia/reperfusion (IR) injury leads to overproduction of Reactive Oxygen Species (ROS), and disrupts membrane potential that contributes to cell death. The aim of this study was to determine if naringin (NAR), trimetazidine (TMZ) or their combination, protect the kidney mitochondrial from IR injury. Forty rats were randomly allocated into five groups, harboring eight rats each: Sham, IR, NAR (100 mg/kg), TMZ (5 mg/kg) and NAR plus TMZ. Ischemia was induced by obstructing both renal pedicles for 45 min, followed by reperfusion for 4 hours. The mitochondria were isolated to examine the ROS, Malondialdehyde (MDA), Glutathione (GSH), mitochondrial membrane potential (MMP) and mitochondrial viability (MTT). Our findings indicated that IR injury resulted in excessive ROS production, increased MDA levels and decreased GSH, MMP and MMT levels. However, NAR, TMZ or their combination reversed these changes. Interestingly, a higher protection was noted with the combination of both, compared to each drug alone. We speculate that this combination demonstrates a promising process for controlling renal failure, especially with the poor clinical outcome, acquired with NAR alone. This study revealed that pretreatment their combination serves as a promising compound against oxidative stress, leading to suppression of mitochondrial stress pathway and elevation of GSH level.

The effects of silymarin plus glutathione on the prevention of liver ischemia-reperfusion injury

Abstract Liver ischemia-reperfusion (IR) injury is a major clinical trouble encountered in clinical practice. This study aimed to examine the therapeutic effects of silymarin (SM) plus glutathione (GSH) on hepatic IR injury using a rat model of liver IR. Fifty male rats were randomly divided into five groups, each consisting of 10 rats as follows: Sham, IR, SM-IR, GSH-IR and SM plus GSH-IR. All groups except sham were subjected to 30-min ischemia and 24-h reperfusion. The treated groups received 100 mg/kg of SM, GSH and a mixture of SM plus GSH, 60 min prior to the IR. After a period of 24 h, blood and liver samples were collected for biochemical and histopathological evaluations. Pretreatment with SM, GSH and SM plus GSH before hepatic IR significantly decreased IR-induced elevations of aminotransferases, and significantly reduced the histopathological damage scores of the liver in the late phase of IR injury. Moreover, SM plus GSH treatment prior to liver IR significantly suppressed inflammatory process and oxidative stress as demonstrated by attenuations in tumor necrosis factor-α, myeloperoxidase and the thiobarbituric acid-reactive substances. These findings suggest that administration of SM plus GSH prior to liver IR may protect the liver parenchyma from the effects of an IR injury

Protection of intestinal immune barrier against ischemia/reperfusion injury in a swine model using anisodamine hydrobromide

Abstract Intestinal ischemia/reperfusion (I/R) causes barrier impairment and bacterial influx. This study explored the protective effects of anisodamine hydrobromide (AH) on intestinal I/R injury caused by cardiopulmonary resuscitation (CPR) after cardiac arrest (CA). After successful CPR, minipigs were randomly divided into two groups (n = 8): saline and AH (4 mg/kg), and then treated with saline or AH via central venous injection, respectively. The same procedures without ventricular fibrillation initiation were conducted in the Sham group (n = 8). Levels of interferon gamma (IFN-γ) and interleukin 4 (IL-4) were measured at different time points (0, 0.5, 1, 2, 4, and 6 h) in serum and 6 h in gut associated lymphoid tissues (GALTs) after the return of spontaneous circulation (ROSC) to evaluate changes in the proportion of T-helper type 1 (Th1) and T-helper type 2 (Th2). Moreover, the positive culture rates of GALTs were examined to evaluate bacterial translocation. AH treatment markedly alleviated aberrant arterial blood gas and hemodynamics as well as intestinal macroscopic and morphological changes after CPR. Moreover, AH treatment significantly increased IFN-γ and decreased IL-4 in both serum and GALTs. Furthermore, AH treatment dramatically decreased positive bacterial growth in GALTs. AH treatment mitigated immunosuppression caused by intestinal I/R and protected the intestinal immune barrier against bacterial translocation, thereby reducing the risk of secondary intestinal infection

Angiotensin II type 2 receptor agonist, compound 21, prevents tubular epithelial cell damage caused by renal ischemia.

During ischemic acute kidney injury (AKI), loss of cytoskeletal integrity and disruption of intercellular junctions are rapid events in response to ATP depletion. Angiotensin II type 2 receptor (AT2R) is overexpressed in injury situations and its stimulation by angiotensin II (AngII) is related to beneficial renal effects. Its role on ischemic AKI has not been deeply studied. The aim of the present study was to investigate whether pretreatment with the AT2R agonist, C21, prevents ischemic renal epithelial cell injury. Studies in a model of 40 min of renal ischemia followed by 24 h of reperfusion (IR) in rats demonstrated that C21 pretreatment attenuated renal dysfunction and induced better preservation of tubular architecture. In addition, we studied the expression of Rho GTPases, RhoA and Cdc42, since they are key proteins in the regulation of the actin cytoskeleton and the stability of epithelial intercellular junctions. IR downregulated RhoA and Cdc42 abundance in rat kidneys. C21 pretreatment prevented RhoA reduction and increased Cdc42 abundance compared to controls. We also used an in vitro model of ATP depletion in MDCK cells grown on filter support. Using immunofluorescence we observed that in MDCK cells, C21 pretreatment prevented the ATP depletion-induced reduction of actin in brush border microvilli and in stress fibers. Moreover, C21 prevented membrane E-cadherin reduction, and RhoA and Cdc42 downregulation. The present study describes for the first time a renoprotective effect of the AT2R agonist, C21, against AKI, and provides evidence supporting that stimulation of AT2R triggers cytoprotective mechanisms against an ischemic event.

Mitotherapy: Unraveling a Promising Treatment for Disorders of the Central Nervous System and Other Systemic Conditions.

Mitochondria are key players of aerobic respiration and the production of adenosine triphosphate and constitute the energetic core of eukaryotic cells. Furthermore, cells rely upon mitochondria homeostasis, the disruption of which is reported in pathological processes such as liver hepatotoxicity, cancer, muscular dystrophy, chronic inflammation, as well as in neurological conditions including Alzheimer's disease, schizophrenia, depression, ischemia and glaucoma. In addition to the well-known spontaneous cell-to-cell transfer of mitochondria, a therapeutic potential of the transplant of isolated, metabolically active mitochondria has been demonstrated in several in vitro and in vivo experimental models of disease. This review explores the striking outcomes achieved by mitotherapy thus far, and the most relevant underlying data regarding isolated mitochondria transplantation, including mechanisms of mitochondria intake, the balance between administration and therapy effectiveness, the relevance of mitochondrial source and purity and the mechanisms by which mitotherapy is gaining ground as a promising therapeutic approach.

Bioelectric, tissue, and molecular characteristics of the gastric mucosa at different times of ischemia.

Gastrointestinal ischemia may be presented as a complication associated with late shock detection in patients in critical condition. Prolonged ischemia can cause mucosal integrity to lose its barrier function, triggering alterations that can induce organ dysfunction and lead to death. Electrical impedance spectroscopy has been proposed to identify early alteration in ischemia-induced gastric mucosa in this type of patients. This work analyzed changes in impedance parameters, and tissue and molecular alterations that allow us to identify the time of ischemia in which the gastric mucosa still maintains its barrier function. The animals were randomly distributed in four groups: Control, Ischemia 60, 90, and 120 min. Impedance parameters were measured and predictive values were determined to categorize the degree of injury using a receiver operating characteristic curve. Markers of inflammatory process and apoptosis (iNOS, TNFα, COX-2, and Caspase-3) were analyzed. The largest increase in impedance parameters occurred in the ischemia 90 and 120 min groups, with resistance at low frequencies (RL) and reactance at high frequencies (XH) being the most related to damage, allowing prediction of the occurrence of reversible and irreversible tissue damage. Histological analysis and apoptosis assay showed progressive mucosal deterioration with irreversible damage (p < 0.001) starting from 90 min of ischemia. Furthermore, a significant increase in the expression of iNOS, TNFα, and COX-2 was identified in addition to apoptosis in the gastric mucosa starting from 90 min of ischemia. Tissue damage generated by an ischemia time greater than 60 min induces loss of barrier function in the gastric mucosa.

Vegfa promoter gene hypermethylation at HIF1α binding site is an early contributor to CKD progression after renal ischemia.

Chronic hypoxia is a major contributor to Chronic Kidney Disease (CKD) after Acute Kidney Injury (AKI). However, the temporal relation between the acute insult and maladaptive renal response to hypoxia remains unclear. In this study, we analyzed the time-course of renal hemodynamics, oxidative stress, inflammation, and fibrosis, as well as epigenetic modifications, with focus on HIF1α/VEGF signaling, in the AKI to CKD transition. Sham-operated, right nephrectomy (UNx), and UNx plus renal ischemia (IR + UNx) groups of rats were included and studied at 1, 2, 3, or 4 months. The IR + UNx group developed CKD characterized by progressive proteinuria, renal dysfunction, tubular proliferation, and fibrosis. At first month post-ischemia, there was a twofold significant increase in oxidative stress and reduction in global DNA methylation that was maintained throughout the study. Hif1α and Vegfa expression were depressed in the first and second-months post-ischemia, and then Hif1α but not Vegfa expression was recovered. Interestingly, hypermethylation of the Vegfa promoter gene at the HIF1α binding site was found, since early stages of the CKD progression. Our findings suggest that renal hypoperfusion, inefficient hypoxic response, increased oxidative stress, DNA hypomethylation, and, Vegfa promoter gene hypermethylation at HIF1α binding site, are early determinants of AKI-to-CKD transition.

P-selectin deficiency promotes liver senescence in sickle cell disease mice.

Sickle cell disease (SCD) is caused by a homozygous mutation in the ß-globin gene, which leads to erythrocyte sickling, vasoocclusion, and intense hemolysis. P-selectin inhibition has been shown to prevent vasoocclusive events in patients with SCD; however, the chronic effect of P-selectin inhibition in SCD remains to be determined. Here, we used quantitative liver intravital microscopy in our recently generated P-selectin-deficient SCD mice to show that chronic P-selectin deficiency attenuates liver ischemia but fails to prevent hepatobiliary injury. Remarkably, we find that this failure in resolution of hepatobiliary injury in P-selectin-deficient SCD mice is associated with the increase in cellular senescence and reduced epithelial cell proliferation in the liver. These findings highlight the importance of investigating the long-term effects of chronic P-selectin inhibition therapy on liver pathophysiology in patients with SCD.

Effect of intramuscular baculovirus encoding mutant hypoxia-inducible factor 1-alpha on neovasculogenesis and ischemic muscle protection in rabbits with peripheral arterial disease.

BACKGROUND AIMS: Peripheral arterial disease (PAD) is a progressive, disabling ailment for which no effective treatment exists. Gene therapy-mediated neovascularization has emerged as a potentially useful strategy. We tested the angiogenic and arteriogenic efficacy and safety of a baculovirus (BV) encoding mutant, oxygen-resistant hypoxia-inducible factor 1-alpha (mHIF-1α), in rabbits with PAD. METHODS: After assessing the transfection efficiency of the BV.mHIF-1α vector and its tubulogenesis potential in vitro, we randomized rabbits with experimental PAD to receive 1 × 109 copies of BV.mHIF-1α or BV.null (n = 6 per group) 7 days after surgery. Two weeks post-treatment, collateralization (digital angiography) and capillary and arteriolar densities (immunohistochemistry) were measured in the posterior limbs. Ischemic damage was evaluated in adductor and gastrocnemius muscle samples. Tracking of viral DNA in injected zones and remote tissues at different time points was performed in additional rabbits using a BV encoding GFP. RESULTS: Angiographically visible collaterals were more numerous in BV.mHIF-1α-treated rabbits (8.12 ± 0.42 vs 6.13 ± 1.15 collaterals/cm2, P < 0.05). The same occurred with arteriolar (27.9 ± 7.0 vs 15.3 ± 4.0 arterioles/mm2) and capillary (341.8 ± 109.9 vs 208.8 ± 87.7 capillaries/mm2, P < 0.05) densities. BV.mHIF-1α-treated rabbits displayed less ischemic muscle damage than BV.null-treated animals. Viral DNA and GFP mRNA were detectable only at 3 and 7 days after injection in hind limbs. Neither the virus nor GFP mRNA was detected in remote tissues. CONCLUSIONS: In rabbits with PAD, BV.mHIF-1α induced neovascularization and reduced ischemic damage, exhibiting a good safety profile at 14 days post-treatment. Complementary studies to evaluate its potential usefulness in the clinic are needed.

Effect of preconditioning and postoperative hyperbaric oxygen therapy on colonic anastomosis healing with and without ischemia in rats.

PURPOSE: To investigate the effect of hyperbaric oxygen therapy on colonic anastomosis healing with and without ischemia in rats. METHODS: Forty female rats underwent segmental resection of 1 cm of the left colon followed by end-to-end anastomosis. They were randomly assigned to four groups (n=10 each), a sham group; two groups were submitted to Hyperbaric Oxygen therapy (HBOT) with and without induced ischemia and the induced ischemia group without HBOT. The HBOT protocol evaluated was 100% O2 at 2.4 Atmosphere absolute pressure (ATA) for 60 minutes, two sessions before as a preconditioning protocol and three sessions after the operation. Clinical course and mortality were monitored during all experiment and on the day of euthanasia on the fourth day after laparotomy. Macroscopic appearance of the abdominal cavity were assessed and samples for breaking strength of the anastomosis and histopathological parameters were collected. RESULTS: There was no statistically significant difference in mortality or anastomosis leak between the four experimental groups. Anastomosis breaking strength was similar across groups. CONCLUSION: The HBOT protocol tested herein at 2.4 ATA did not affect histopathological and biomechanical parameters of colonic anastomotic healing, neither the clinical outcomes death and anastomosis leak on the fourth day after laparotomy.

Induction of selective liver hypothermia prevents significant ischemia/reperfusion injury in Wistar rats after 24 hours.

Purpose To investigate the effects of induction of selective liver hypothermia in a rodent model. Methods Seven male Wistar rats were subjected to 90 minutes of partial 70% liver ischemia and topic liver 26°C hypothermia (H group). Other seven male Wistar rats were subjected to 90 minutes of partial 70% normothermic liver ischemia (N group). Five additional rats underwent a midline incision and section of liver ligaments under normothermic conditions and without any liver ischemia (sham group). All animals were sacrificed 24-h after reperfusion, and livers were sampled for analyses. Pathology sections were scored for sinusoidal congestion, ballooning, hepatocelllular necrosis and the presence of neutrophilic infiltrates. Results At the end of the experiment, liver tissue expressions of TNF-ɑ, IL-1ß, iNOS and TNF-ɑ/IL-10 ratio were significantly reduced in the H group compared to N group, whereas IL-10 and eNOS were significantly increased in H group. Histopathological injury scores revealed a significant decrease in ischemia/reperfusion (I/R) injuries in H group. Conclusion Selective liver hypothermia prevented I/R injury by inhibiting the release of inflammatory cytokines, preserves microcirculation, prevents hepatocellular necrosis and leukocyte infiltration, allowing maintenance of the liver architecture.