Effect of Yes-associated protein in regulation of electroacupuncture pretreatment on cerebral ischemia reperfusion injury rats / 中国针灸

OBJECTIVE@#To observe the effect of electroacupuncture (EA) pretreatment on inflammatory reaction, apoptosis and expression of Yes-associated protein (YAP) of ischemic penumbra of cerebral cortex in cerebral ischemia reperfusion injury rats, and to explore the possible mechanism of its neuroprotection effect.@*METHODS@#A total of 84 SD rats were randomized into a sham operation group (12 rats), a model group (18 rats), an EA group (18 rats), an EA+YAP virus transfection group (18 rats) and an EA+virus control group (18 rats). Except for the sham operation group, thread embolization method was adopted to establish the middle cerebral artery occlusion (MCAO) model in rats of the other groups. EA was applied at "Baihui" (GV 20) and "Dazhui" (GV 14) for 30 min in the 3 EA intervention groups 2 h before model establishment, disperse-dense wave, 2 Hz/15 Hz in frequency and 1 mA in intensity. Adenovirus transfection technique was used to induce gene silencing of YAP in the EA+YAP virus transfection group, and adenovirus vectors was injected as negative control in the EA+virus control group 4 d before model establishment. Twenty-four hours after model establishment, neurological function score was evaluated, the relative cerebral infarction area was observed by TTC staining, the apoptosis in the ischemic penumbra of cerebral cortex was detected by TUNEL staining, the levels of inflammatory factors IL-1β, IL-6 and TNF-α in the ischemic penumbra of cerebral cortex was detected by ELISA method, the expression of YAP was detected by Western blot and immunofluorescence.@*RESULTS@#Compared with the sham operation group, the expression of YAP was increased in the model group (@*CONCLUSION@#Electroacupuncture pretreatment can effectively improve the ischemia reperfusion injury, its mechanism may be related to up-regulating the expression of YAP in the ischemic penumbra of cerebral cortex and relieving the apoptosis and inflammatory reaction.

Combinación de bardoxolona y DMF Mejora la isquemia cerebral/reperfusión Lesión en ratas macho / Combination of Bardoxolone and DMF Ameliorates Cerebral Ischemia / Reperfusion Injury in Male Rats

Background: Ischemic stroke has been ranked as the second cause of death in patients worldwide. Inflammation which is activated during cerebral ischemia/reperfusion (I/R) is an important mechanism leading to brain injury. The present study aimed to investigate the effect of Berberine on cerebral I/R injury and the role of inflammation in this process. Material and Methods: The study was carried out on 36 Wistar-albino rats, divided into four groups including: Sham group, I/R group, I/R+ (control-vehicle DMSO) and I/R+ Berberine 5 mg/kg injected intraperitoneally 1 hour before induction of ischemia. Measurement of brain tissue IL-1ß, ICAM1, caspase-3, Notch 1 and Jagged 1 was done after one hour of reperfusion in addition to assessment of the brain infracted area and histopathological analysis. Results: Berberine attenuates cerebral I/R injury induced increase in inflammatory cytokine (IL-1ß), adhesion molecule (ICAM-1) and proapoptotic enzyme (caspase-3). Additionally, it reduces the size of infracted area and histopathological damage; such protective effect could be mediated by Notch 1 signaling pathway since Berberine further unregulated the increased levels of Notch 1 and Jagged 1 seen in brain with I/R injury. Conclusions: Berberine has a neurocytoprotective outcome against cerebral I/R injury which is manifested as anti-inflammatory anti-apoptotic effect that preserved cell structure and viability, in the meantime this effect could be mediated by Notch 1 signaling pathway.

Liver ischemia and reperfusion injury. Pathophysiology and new horizons in preconditioning and therapy

Abstract It is well known that during hepatic operative procedures, it is often critical that the irrigation is interrupted to avoid possible bleeding, blood transfusions, variable intensities, and their short and long-term consequences. It was believed in the past that the flow interruption should not exceed 20 minutes, which limited the use of this maneuver. However, it has been postulated that ischemia could be maintained for more than 60 minutes in healthy livers. The present paper review includes: 1) A brief introduction to justify the rationale of the review design; 2) Aspects of the pathophysiology of the three stages of the liver ischemia-reperfusion injury; 3) The innate and acquired immunity; 4) Oxidative stress; 5) Apoptosis and autophagy, Some essential biomarkers (Tumor Necrosis Factor-α, nitric oxide, metalloproteinases); and, finally; 6) Preventive ("cheating") strategies, non-pharmacological and pharmacological options to treat the liver IR injury.

Effect of mild hypothermia on renal ischemia/reperfusion injury after cardiopulmonary resuscitation in a swine model

Abstract Purpose: To investigate the effect of intravascular cooling on renal function after resuscitation. Methods: Twenty four pigs were randomized into three groups (n=8 in each group): therapeutic hypothermia group (TH group), normothermia group (NH group) and sham operation group (SHAM group). After 6 minutes of untreated VF, CPR was performed. Upon ROSC, the TH group received the intravascular cooling. The NH and SHAM group did not undergo therapeutic hypothermia. Haemodynamic parameters were recorded. The bloods were analyzed for serum creatinine (sCr), CysC and NGAL. The kidney was surgically removed observe pathologic changes under a light microscope. Results: The sCr increased in both TH and NH groups after ROSC, compared to baseline. Between two groups, the sCr and creatinine clearance (Cc) showed lower level in the TH group. The urine volume per hour in the TH group were higher during cooling. After resuscitation, NGAL and CysC in the NH group were higher than in the TH group. Under the light microscope, compared with the TH group, the renal injury was prominent in the NH group. Conclusion: Mild hypothermia had a protection to renal ischemia reperfusion injury after resuscitation.

Low-energy shock wave preconditioning reduces renal ischemic reperfusion injury caused by renal artery occlusion

Abstract Purpose: To evaluate whether low energy shock wave preconditioning could reduce renal ischemic reperfusion injury caused by renal artery occlusion. Methods: The right kidneys of 64 male Sprague Dawley rats were removed to establish an isolated kidney model. The rats were then divided into four treatment groups: Group 1 was the sham treatment group; Group 2, received only low-energy (12 kv, 1 Hz, 200 times) shock wave preconditioning; Group 3 received the same low-energy shock wave preconditioning as Group 2, and then the left renal artery was occluded for 45 minutes; and Group 4 had the left renal artery occluded for 45 minutes. At 24 hours and one-week time points after reperfusion, serum inducible nitric oxide synthase (iNOS), neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), creatinine (Cr), and cystatin C (Cys C) levels were measured, malondialdehyde (MDA) in kidney tissue was detected, and changes in nephric morphology were evaluated by light and electron microscopy. Results: Twenty-four hours after reperfusion, serum iNOS, NGAL, Cr, Cys C, and MDA levels in Group 3 were significantly lower than those in Group 4; light and electron microscopy showed that the renal tissue injury in Group 3 was significantly lighter than that in Group 4. One week after reperfusion, serum NGAL, KIM-1, and Cys C levels in Group 3 were significantly lower than those in Group 4. Conclusion: Low-energy shock wave preconditioning can reduce renal ischemic reperfusion injury caused by renal artery occlusion in an isolated kidney rat model.

Remote limb ischemic post-conditioning attenuates ischemia-reperfusion injury in rat skin flapby limiting oxidative stress

PURPOSE: To investigate the effect of remote ischemic post-conditioning (RIPoC) against ischemia-reperfusion (I/R) injury on flaps of rats. METHODS: Sprague-Dawley rats were randomized into the Sham, Control, RIPoC1 and RIPoC2 groups. All the animals were submitted to a 5×4 cm superficial inferior epigastric artery flap. Eight hours of flap ischemia was induced and two protocols of limb RIPoC were applied. Tissue MDA level and SOD activity in 24-h reperfusion were assessed. Flap survival was assessed 7 days postoperatively. RESULTS: Compared to the Control group, the RIPoC1 group showed statistically decreased MDA level at 6-, 12-, and 24-h reperfusion (P = 0.01, P < 0.01 and P < 0.01, respectively), and statistically increased SOD activity at 12- and 24-h reperfusion (P < 0.05 and P < 0.01, respectively). Flap survival rate on the 7th day was significantly higher in the RIPoC1 group than the control group (47.9 ± 6.4 vs . 29.4 ± 7.1 %, P < 0.01). CONCLUSION: Three cycles of 5-min Limb remote ischemic post-conditioning rather than a single cycle of 15-min limb RIPoC has protective effect on flaps against ischemia-reperfusion injury by attenuating oxidative stress.

Effects of Human Umbilical Cord Mesenchymal Stem Cells on Renal Ischaemia-reperfusion Injury in Rats

Objective This study aims to observe the function of umbilical cord-mesenchymal stem cells (UC-MSCs) labelled with enhanced green fluorescent protein (eGFP) in the repair of renal ischaemia-reperfusion (I/R) injury, to determine the effects on inflammatory cascade in an established rat model and to explore possible pathogenesis. Materials and Methods Sixty rats were randomly divided into three groups: the sham-operated, I/R and UC-MSC treatment groups. All rats underwent right nephrectomy. Ischaemia was induced in the left kidney by occlusion of the renal artery and vein for 1hour, followed by reperfusion for 24 hours or 48 hours. Kidney samples were collected to observe morphological changes. Immunohistochemistry was performed to assess the expression of intercellular adhesion molecule 1 (ICAM-1) in the renal tissue sample, as well as the number of infiltrating polymorphonuclear neutrophils (PMNLs) and UC-MSCs with positive eGFP. Results Renal histopathological damages and the expression of ICAM-1 and PMNL increased significantly in the I/R group compared with those in the sham-operated group, whereas the damages were less conspicuous in the UC-MSC treatment group. Conclusions Renal ICAM-1, which mediated PMNL infiltration and contributed to renal damage, was significantly up-regulated in the I/R group. UC-MSCs were identified to inhibit these pathological processes and protect the kidney from I/R injury. .

Protective effects of abdominal electroacupuncture on oxidative stress and inflammation due to testis torsion/detorsion in rats

PURPOSE: To evaluate the effects of acupuncture (Ac) and electroacupuncture (EAc) on oxidative stress and inflammation in testis torsion/detorsion (T/D) model in rats. METHODS: Thirty male Wistar rats were randomized into five groups. G1 Group (Sham) served as control. The remaining groups were submitted to spermatic cord torsion (720°) for 3 hours, followed by detorsion and reperfusion for 4 hours. Before detorsion G3, G4 and G5 rats were treated with Ac, EAc 2Hz and EAc 10 Hz, respectively, applied to acupoint Gulai (S-29) bilaterally under anesthesia for 5 minutes. Next, the testes were detorsioned and reperfused for 4 hours. Afterwards, blood samples and the right testis were collected for biochemical assays: reduced Glutathione (GSH), Malonaldehyde (MDA), Myeloperoxidase (MPO). RESULTS: EAc stimulation (2 and 10 Hz) promoted significant increase in concentrations of GSH in plasma and testis of G4-G5 rats, compared with G1. There was significant increase of tissue MDA in groups G4-G5 and plasma MDA in all groups, compared with G1. There was a significant reduction in MPO activity in groups G4-G5 compared with G1. CONCLUSION: Electroacupuncture stimulation (2 and 10 Hz) attenuates oxidative stress and inflammatory response in rats subjected to testicular torsion/detorsion. .

Effects of ischemic preconditioning and cilostazol on muscle ischemia-reperfusion injury in rats

PURPOSE: To evaluate effects of ischemic preconditioning and Cilostazol on muscle ischemia-reperfusion injury. METHODS: Male Wistar rats were submitted to muscle ischemic and reperfusion injury (4h of the left common iliac artery occlusion followed by 1h of reperfusion). Five experimental groups were constituted: Control group (n=4); Ischemia-Reperfusion (IR, n=5); Ischemic preconditioning group (IP, n=6); Ischemia-Reperfusion group treated with cilostazol (IRCi, n=6) and Ischemic preconditioning group treated with cilostazol (IPCi, n=6). At the end, left gracile muscle was removed and embedded in paraffin. Histopathology, neutrophil infiltration, myocyte necrosis and edema were analyzed. RESULTS: When compared with the control group, IR group showed increased neutrophil infiltration, severe necrosis and edema. There was significant difference between myocytes necrosis of IR group and IP group. There was no difference between the histopathological changes between IP, IRCi and IPCi groups. CONCLUSIONS: The model of IR caused severe muscle injury in the rat hind limb and ischemic preconditioning has a protective effect, reducing myocyte necrosis, however, treatment with cilostazol and also the association between cilostazol and preconditioning has no protective effect on the skeletal muscle subjected to ischemia and reperfusion injury. .

possible protective effect of exercise on liver damage following hind-limb ischemia reperfusion injury in the adult male albino rat: light and electron microscopic study

Hind-limb ischemia-reperfusion [I/R] injury is not limited to the lower extremities; it also causes damage to remote organs. This study was undertaken to investigate the role of exercise in attenuating remote hepatic damage following hind-limb I/R injury. Forty-five adult male rats were divided into three groups: the control group, the I/R group, and the exercise+I/R group. The rats were left to swim for 1 h, five times a week, for 4 weeks before I/R. Bilateral hind-limb ischemia was induced by application of rubber bands above the greater trochanter for 3 h. Blood samples were taken after 3 h of reperfusion for determination of malondialdehyde, superoxide dismutase, tumor necrosis factor-alpha, and interleukin-6. Liver specimens were processed for light and electron microscopic study. In the I/R group, the superoxide dismutase level decreased and plasma levels of malondialdehyde, tumor necrosis factor-alpha, and interleukin-6 significantly increased when compared with the control group. Light microscopic examination showed hepatocytes with vacuolated cytoplasm, dilated blood sinusoids, and portal vessels. An extensive amount of collagen fibers around portal tracts and intense immune reaction for caspase-3 were observed. The ultrastructure showed hepatocytes with swollen mitochondria and disrupted cristae and others with an electron-dense matrix. Kupffer cells showed apoptotic bodies. Ito cells appeared surrounded by wide areas of collagen fibers. The exercise+I/R group showed significant attenuation of the biochemical and histological alterations of I/R-induced liver injury. Exercise could attenuate remote liver damage following hind-limb I/R injury

Effects of hyperbaric oxygen therapy on the liver after injury caused by the hepatic ischemia-reperfusion process

PURPOSE: To evaluate the effects of hyperbaric oxygen on rats submitted to hepatic ischemia and reperfusion. METHODS: Twenty-three Wistar rats were divided at random into 3 groups: SHAM, rats submitted to surgical and anesthetic stress without induction of hepatic ischemia/reperfurion; I/R, rats submitted to total ischemia of the hepatic pedicle for 25 min followed by 5 min of reperfusion; HBOI/R, rats submitted to 60 min of hyperbaric oxygen therapy at a pressure of 2 absolute atmospheres immediately after the experimental protocol of ischemia/reperfusion. Hepatic function was evaluated by quantitation of serum alanine aminotranferase (ALT) and aspartate aminotransferase (AST), and by mitochondrial function through the determination of states 3 and 4 of mitochondrial respiration, respiratory control ratio (RCR) and mitochondrial swelling. Data were analyzed by the Mann-Whitney test, with the level of significance set at p <0.05. RESULTS: There was a significant difference in state 3 values for the SHAM group vs I/R and I/R vs IRHBO, in state 4 values for the SHAM group vs I/R; and in mitochondrial swelling for the SHAM groups vs I/RHBO, SHAM vs I/R, and IR vs I/RHBO. CONCLUSION: The use of hyperbaric oxygen after I/R improved in a relative manner both the production of energy and the effects on the mitochondrial wall. .

Effect of hyperbaric hepatic hyperoxia on the liver of rats submitted to intermittent ischemia/reperfusion injury

PURPOSE: To determine the effect of hyperbaric hyperoxia as hepatic preconditioning on hepatocellular integrity in rats submitted to intermittent hepatic ischemia/reperfusion injury. METHODS: Twenty male Wistar rats were divided into 4 groups (SHAM, I/R, HBO-I/R and CONTROL). The surgical technique consisted of total clamping of the hepatic pedicle for 15 min, followed by reperfusion for 5 min, performed twice. The application of hyperbaric oxygen (HBO) was carried out in a collective chamber (simultaneous exposure of 4 rats) pressurized directly with oxygen at 2 ATA for 60 min. Tissue malondialdehyde (MDA) levels were determined and blood samples were collected for the determination of serum AST and ALT levels. Data were analyzed statistically by the Mann-Whitney test, with the level of significance set at p < 0.05. RESULTS: A statistically significant difference in MDA (p< 0.05) was observed between control and HBO-I/R, but not between control and I/R. Regarding AST, there was a difference between control and I/R and HBO-I/R. Analysis of ALT revealed a significant difference between control and I/R (p<0.05) and between I/R and HBO-I/R, with no difference between control and HBO-IR. CONCLUSION: Hyperoxic preconditioning proved to be favorable regarding alanine transaminase, but not aspartate aminotranserase or malondialdehyde levels. .

Hyperoxic preconditioning in partial liver ischemia

PURPOSE: To evaluate the effect of the hyperbaric oxygen (HBO) treatment as a pre-conditioning for I/R effects in the liver ischemia. METHODS: Fifty-seven male Wistar rats (260-300g) were submitted to the following procedures: SHAM; I/R, rats submitted to I/R, consisting of partial ischemia of 70% of the liver for 90 minutes followed by 15 minutes of reperfusion; HBO I/R 1 ATA, 30 minutes of HBO treatment at the pressure of 1 absolute atmosphere (ATA) during the ischemia time. HBO I/R 2 ATA, 30 minutes of HBO (2 ATA) during the ischemia time. Pre HBO I/R 30', rats submitted to 30 minutes of HBO (2 ATA) immediately before the I/R time. Pre HBO I/R 90', rats submitted to 90 minutes of HBO (2 ATA) immediately before the I/R time. RESULTS: There was a significant worsening of all the parameters of mitochondrial energy production (state 3, 4, RCR and Swelling) in the I/R group, when compared to the Sham group (I/R <Sham, p<0.05). There was also a significant worsening in state 4, RCR and mitochondrial edema in the Pre HBO I/R 90' group compared to the I/R group. Hepatic enzyme concentrations were significantly higher in the I/R group. CONCLUSION: The use of hyperbaric oxygen before and during I/R did not improve the production of hepatocellular energy reduced by I/R, nor did it prevent the installation of mitochondrial edema induced by Iischemia/reperfusion. .

Heart injury following intestinal ischemia reperfusion in rats is attenuated by association of ischemic preconditioning and adenosine

PURPOSE: To investigate the effect of ischemic preconditioning (IPC) and adenosine as strategies to protect cardiac injury caused by intestinal IR in rats, based on increasing in adenosine bioavailability and improvement of cell energy state by IPC. METHODS: Male Wistar rats were submitted to 60 minutes of intestinal ischemia and 120 minutes of reperfusion. Intravenous injections of saline or Adenosine (AD) was administered five minutes before ischemia, five minutes before reperfusion and after 55 minutes reperfusion. Cardiac samples were obtained, fixed in formalin solution, embedded in paraffin, and sections of 5 μm were stained by hematoxylin-eosin. Histological analysis of myocardium was performed according occurrence of necrosis signs: piknosis, band contraction, eosinophilic cytoplasm, karyorrhexis and vacuolization (score - zero to 5). RESULTS: The groups submitted to ischemia alone (I=4.0), and reperfusion (IR=4.5) showed highest level of lesion compared to the others (I+IPC=3.3, IR+IPC=3.6, I+AD=3.0, IR+AD=3.8). The most interesting result was association of IPC and AD in IR model (IR+IPC+AD=1.2, p=0.002), showing preservation of the heart tissue, with fibers showing typical cross-striations and nuclei characteristics. Rare and small areas of tissue necrosis was observed and suggestion of capillaries congestion. CONCLUSION: Intestinal ischemia reperfusion promotes cardiac tissue injury. Ischemic preconditioning in association with adenosine is an efficient strategy to protect the heart against ischemia and reperfusion injury. .

Hyperbaric oxygen therapy and ischemia and reperfusion: a valuable association to attenuate ischemic lesion and hepatic reperfusion

PURPOSE: To investigate the consequences of the association between hyperbaric oxygen therapy and hepatic ischemia / reperfusion. METHODS: Wistar rats were divided into three groups: SHAM, rats submitted to surgical stress and anesthetic but not hepatic ischemia or reperfusion, I / R, rats submitted to total hepatic pedicle ischemia for 30 min, followed by 5 min of reperfusion; HBO120, rats submitted to 120 min of hyperbaric oxygen therapy at two absolute atmospheres and immediately after submitted to the experimental protocol of ischemia and reperfusion. The preservation of the hepatic function was evaluated by determining mitochondrial swelling and malondialdehyde tissue level, as well as alanine aminotransferase and aspartate aminotranferase serum levels. The results were analyzed using the Mann-Whitney test and differences were considered significant for p<0.05. RESULTS: There were significant differences in values: mitochondrial swelling of the I / R group compared to SHAM and HBO120; malondialdehyde between SHAM vs. I / R, SHAM vs HBO120, and I / R vs HBO120, alanine aminotransferase between SHAM vs. I / R . There was no significant difference between groups in aspartate aminotransferase serum levels. CONCLUSION: The association between hyperbaric oxygen therapy and hepatic ischemia and reperfusion process was positive.

effect of selenium on induced ischemia / reperfusion injury in ovaries of female albino rat: a histological and biochemical study

Ovarian torsion is a serious cause of gynecological surgical emergency. Recently, a conservative approach including detorsion and releasing the pedicle to preserve fertility was advocated. However, detorsion worsens the tissue injury leading to ischemia/reperfusion [I/R] and production of reactive oxygen species. Selenium [Se] is an essential trace element and a component of the antioxidant enzymes that protect the cells against the effects of free radicals. This study was designed to investigate the possible protective effect of Se on I/R-induced injury of ovary in a rat model [using histological and biochemical studies]. Twenty-six adult female albino rats were divided into three groups: group I [control], group II [the I/R group] including rats exposed to right ovarian ischemia for 3 h and then reperfused for 12 h, and group III [the Se-treated group] including rats exposed to I/R as group II, in addition to 0.2 mg/kg Se injected intraperitoneally 30 min before reperfusion. Ovarian tissues were excised for histological, immunohistochemical, morphometric, and biochemical studies. Statistical analysis was performed. In the I/R group, the right ovary showed secondary follicles with desquamated cells into the antral cavity, congested vessels, multiple distorted follicles, massive extravasated red blood cells [RBCs], multiple dark nuclei, and vacuolations in the corpora lutea. The left ovary recruited congested vessels and extravasated RBCs in the corpora lutea. In the Se-treated group, the right ovary revealed some dark nuclei and vacuolations in some atretic follicles besides few extravasated RBCs. A significant increase in the mean area% of caspase-3 immunoreactivity was found in the right ovary in the I/R group compared with the other groups. A significant increase in DNA fragmentation percentage, a significant decrease in reduced glutathione concentration, a significant decrease in catalase activity, and a significant increase in malondialdehyde concentration were found in the I/R group compared with the other groups. Furthermore, administration of Se restored these values to normal levels. Se proved to be effective in preventing tissue damage induced by I/R in rat ovaries

Effects of hyperbaric oxygen (HBO), as pre-conditioning in liver of rats submitted to periodic liver ischemia/reperfusion / Efeitos da oxigenoterapia hiperbárica como pré-condicionamento em fígados de ratos submetidos à lesão hepática de isquemia/reperfusão intermitente

PURPOSE: to assess the effect of hyperbaric oxygen (HBO) as pre-conditioning on periodic liver ischemia/reperfusion injury. METHODS: Thirty-six male Wistar rats were divided into 4 groups (SHAM, I/R , HBO-I/R and CONTROL). The surgical technique consisted of total clamping of the hepatic pedicle for 15 min followed by twice repeated reperfusion for 5 min (unclamping). HBO was applied in a collective chamber (simultaneous exposure of 4 rats) directly pressurized with oxygen at 2 ATA for 60 min. Hepatic mitochondrial function was determined using samples of the median lobe obtained after exactly 5 min of reperfusion for the analysis of mitochondrial respiration based on the determination of states 3 and 4, the respiratory control ratio and the transition of mitochondrial permeability (mitochondrial swelling).Data were analyzed by the Mann-Whitney test and the level of significance was set at p < 0.05. RESULTS: There was a statistically significant difference (p< 0.05) in state 3 between the CONTROL and I/R and HBO-I/R groups, in state 4 between the CONTROL and I/R and HBO-I/R groups; in respiratory control ratio (RCR) between the CONTROL and I/R and HBO-I/R groups and between the CONTROL and Sham groups, and in mitochondrial swelling between the CONTROL and I/R and HBO-/R groups and between the Sham and I/R and HBO-I/R groups. CONCLUSION: In this process of periodic ischemia and reperfusion, hyperbaric pre-conditioning did not improve significantly hepatic mitochondrial function.

OBJETIVO: Avaliar os efeitos da oxigenoterapia hiperbárica (HBO), como pré-condicionamento, em lesão hepática de isquemia/reperfusão intermitente. MÉTODOS: Foram avaliados 36 ratos Wistar machos, distribuídos em 4 grupos (SHAM, I/R , HBO - I/R e CONTROLE). A técnica operatória consistiu em pinçamento total do pedículo hepático durante 15min, seguido de reperfusão por 5 min (desclampeamento), por duas vezes. A aplicação de HBO foi realizada em câmara coletiva (exposição simultânea de 4 ratos) diretamente pressurizada com oxigênio a 2ATA, durante 60min. Determinou-se a função mitocondrial hepática através de amostras do lobo mediano colhidas com exatos 5min de reperfusão para análise da respiração mitocondrial, através da determinação dos estados 3 e 4, razão de controle respiratório e transição de permeabilidade mitocondrial (intumescimento osmótico - swelling mitocondrial).Os resultados foram analisados pelo teste de Mann-Whitney e foi considerado significativo todo valor de p < 0,05. RESULTADOS: Houve diferença estatistica significativa (p< 0,05) no Estado 3 nos grupos CONTROLE vs I/R e HBO - I/R, no Estado 4 nos grupos CONTROLE vs I/R e HBO - I/R; na Razão de controle respiratório(RCR) nos grupos CONTROLE vs I/R e HBO-IRe CONTROLE vs Sham e no Swelling mitocondrial nos grupos CONTROLE vs I/R e HBO - I/R, I/R vs HBO-IRe Sham vs I/R e HBO-IR. CONCLUSÃO: O pré-condicionamento hiperbárico não melhorou a função mitocondrial hepática significativamente neste processo de isquemia e reperfusão intermitente.

Efeito da cinesioterapia na lesão isquêmica e reperfusão em ratos / Effects of kinesiotherapy in ischemic lesion and reperfusion in rats

OBJETIVO: Verificar o efeito da cinesioterapia na funcionalidade do membro pélvico de ratos após lesão isquêmica e reperfusão. MÉTODOS: Foram utilizados 10 ratos, divididos em dois grupos, GI (controle) e GII (cinesioterapia). Todos os animais foram submetidos à isquemia por um período de três horas, seguido de reperfusão tecidual. No Grupo GII foi realizado cinesioterapia sistêmica (natação) não resistida em três sessões semanais de 50 minutos durante quatro semanas, enquanto que no grupo GI os animais permaneceram em repouso. A análise funcional do comportamento motor foi realizada semanalmente. Posteriormente, os animais foram mortos e retirados os músculos sóleo, gastrocnêmio e nervo ciático para análise histopatológica. RESULTADOS: Houve uma recuperação significativa do comportamento motor com o tratamento cinesioterapêutico ao longo das quatro semanas de tratamento. No entanto, na avaliação histológica os tecidos não mostraram alterações morfológicas de lesão e reparação celular. CONCLUSÃO: Não foi possível afirmar que o exercício mostrou-se eficiente na reparação celular, pois, tanto no grupo controle como no experimental, não apresentou diferença histológica. Por outro lado, a cinesioterapia sistêmica apresentou um efeito benéfico na reabilitação funcional após isquemia e reperfusão. Nível de Evidência III, Estudo Caso-Controle.

OBJECTIVE: To investigate the effect of kinesiotherapy on the functionality of the pelvic limb of rats after ischemic and reperfusion injury. METHODS: 10 rats were divided into two groups, GI (control) and GII (kinesiotherapy). All the animals underwent ischemia for a period of three hours, followed by tissue reperfusion. In Group GII, non-resistive systemic kinesiotherapy was performed (swimming) in three weekly sessions of 50 minutes, over a period of four weeks, while the GI animals remained at rest. Functional analysis of motor behavior was evaluated weekly. The animals were then sacrificed, and the soleus, gastrocnemius and sciatic nerve removed for histopathological analysis. RESULTS: There was a significant recovery of motor behavior with kinesiotherapeutic treatment during the four weeks of treatment. However, the histological tissues showed no morphological changes of cell injury and repair. CONCLUSION: It was not possible to affirm that the exercise was effective in cell repair, because neither of the groups (control and experimental) showed any histological difference. On the other hand, systemic kinesiotherapy showed a beneficial effect on functional rehabilitation after ischemia and reperfusion. Level of evidence III, Case-Control Study.

Effect of hyperbaric oxygen therapy on the intestinal ischemia reperfusion injury / Efeito da oxigenoterapia hiperbárica na lesão por isquemia reperfusão intestinal

PURPOSE: Adequate tissue oxygenation is essential for healing. Hyperbaric oxygen therapy (HBOT) has potential clinical applications to treat ischemic pathologies, however the exact nature of any protective effects are unclear at present. We therefore investigated the potential role of HBOT in modulating the ischemia/reperfusion (I/R) injury response in intestinal model of I/R injury. METHODS: Male Wistar rats were subjected to surgery for the induction of intestinal ischemia followed by reperfusion. HBOT was provided before and/or after intestinal ischemia. Cell viability in the intestinal tissue was assessed using the MTT assay and by measuring serum malondealdehyde (MDA). Microvascular density and apoptosis were evaluated by immunohistochemistry. RESULTS: The results indicate that HBOT treatment pre- and post-ischemia reduces lesion size to the intestinal tissue. This treatment increases cell viability and reduces the activation of caspase-3, which is associated with increased number of tissue CD34 cells and enhanced VEGF expression. CONCLUSION: The hyperbaric oxygen therapy can limit tissue damage due to ischemia/reperfusion injury, by inducing reparative signaling pathways.

OBJETIVO: Oxigenação tissular adequada é essencial para cicatrização. Oxigenoterapia hiperbárica (HBOT) tem aplicação clínica para tratar lesões isquêmicas, entretanto a natureza exata dos mecanismos envolvidos permanece incerta. Procuramos investigar o papel potencial da HBOT na modulação da resposta a uma lesão por isquemia reperfusão (I/R) intestinal em modelo de lesão de I/R. MÉTODOS: Ratos machos Wistar foram submetidos à cirurgia para a indução da isquemia intestinal seguida de reperfusão. HBOT foi fornecido antes e / ou após a isquemia intestinal. A viabilidade das células no tecido intestinal foi avaliada através do ensaio de MTT e pela medição malondealdeido (MDA) no plasma. Densidade microvascular e apoptose foram avaliados por imuno-histoquímica. RESULTADOS: Os resultados indicam que o tratamento HBOT pré e pós-isquemia reduz o tamanho da lesão ao tecido intestinal. Este tratamento aumenta a viabilidade celular e reduz a ativação da caspase-3, que está associada com aumento do número de células CD 34 no tecido e da expressão da VEGF. CONCLUSÃO: A oxigenoterapia hiperbárica pode limitar os danos do tecido devido à lesão por isquemia/reperfusão, induzindo às vias de sinalização reparadora.

Neuroprotective effects of selenium and ginkgo biloba extract [EGb761] against ischemia and reperfusion injury in rat brain

To determine the neuroprotective effects of Ginkgo biloba extract [EGb761] and Selenium [Se], and the combination of these agents on ischemia/reperfusion [I/R] injury in a rat model of transient global cerebral I/R. This experimental study took place in the Animal Research Laboratory at Dokuz Eylul University, Izmir, Turkey in the year 2006. Fifty rats were subjected to cerebral I/R induced by right carotid artery occlusion technique for a duration of 45 minutes, and then were treated with EGb761 [50 mg/kg/day, ip] and Se [0.625 mg/kg, ip], alone or in combination for 14 days after surgery. Superoxide dismutase, and glutathione peroxidase activities were measured in the hippocampal tissues from 25 animals. Histopathological examinations were also carried out under light and electron microscopy from the rest of animals. The results suggest that EGb761 has a potent neuroprotective effect against cerebral I/R induced injury in rat brain that is comparable with that of Se. However, the combined use of EGb761 and Se does not further protect from neuronal injury when compared with the use of both agents alone. Our results suggest that administration of EGb761, Se and its combination with EGb761 have significant neuroprotective effects on I/R injury in rats via suppression of oxidative stress