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2.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(9): 1174-1178, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31657349

RESUMO

OBJECTIVE: Contrast induced nephropathy (CIN) is acute renal injury following administration of contrast media during angiographic or other medical procedures, which represents as the third cause of hospital-acquired renal failure. CIN is associated with prolonged hospital stay, increased health-care costs, and undesirable clinical outcome. The risk of CIN includes advanced age and diabetes mellitus. With the rapid development of iconography and the wide application of interventional techniques, the patients with CIN are increasing. The preventive measures of CIN include hydration, using appropriate contrast media, stopping nephrotoxic drugs, ischemic preconditioning, renal replacement therapy, and using appropriate drugs. In this paper, the current status and early prevention progress of CIN will be reviewed from three aspects of the high-risk factors, pathogenesis and prevention, aiming to provide guidance for the early prevention of CIN and explore new research directions.


Assuntos
Lesão Renal Aguda , Meios de Contraste , Precondicionamento Isquêmico , Angiografia , Humanos , Nefropatias , Terapia de Substituição Renal , Fatores de Risco
3.
Acta Cir Bras ; 34(8): e201900805, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618405

RESUMO

PURPOSE: To investigate the effect of sevoflurane preconditioning on ischemia/reperfusion (I/R)-induced pulmonary/hepatic injury. METHODS: Fifty-one Wistar rats were randomly grouped into sham, I/R, and sevoflurane groups. After reperfusion, the structural change of the lung was measured by Smith score, the wet and dry weights (W/D) were determined, malondialdehyde (MDA) myeloperoxidase (MPO) content was determined colorimetrically and by fluorescence, respectively, and matrix metalloprotein-9 (MMP-9) mRNA was quantified by RT-PCR. Biopsy and morphological analyses were performed on liver tissue, activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were determined, and tumor necrosis factor-alpha (TNF-α) level was determined. RESULTS: The sham group showed no changes in tissue structure. Structural lesions in the sevoflurane and I/R groups were mild and severe, respectively. Smith score, W/D, MDA, MPO, and MMP mRNA showed the same trend, and were increased in the I/R group and recovered in the sevoflurane group, compared with the sham group (both P<0.05). AST and ALT were significantly increased compared to the sham group (AST: 655±52.06 vs . 29±9.30 U/L; ALT: 693±75.56 vs . 37±6.71 U/L; P<0.05). In the sevoflurane group, AST and ALT levels were significantly decreased (464±47.71 and 516±78.84 U/L; P<0.001). TNF-α presented similar results. CONCLUSION: The protection of lung and liver by sevoflurane may be mediated by inhibited leukocyte recruitment and MMP-9 secretion.


Assuntos
Anestésicos Inalatórios/uso terapêutico , Precondicionamento Isquêmico/métodos , Fígado/irrigação sanguínea , Pulmão/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Sevoflurano/uso terapêutico , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Modelos Animais de Doenças , Isquemia/prevenção & controle , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Malondialdeído/análise , Peroxidase/análise , Ratos , Ratos Wistar , Traumatismo por Reperfusão/tratamento farmacológico , Fator de Necrose Tumoral alfa/sangue
4.
Plast Reconstr Surg ; 144(4): 619e-629e, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31568298

RESUMO

BACKGROUND: The authors hypothesize that ischemic preconditioning of the recipient site with deferoxamine will increase fat graft survival by enhancing angiogenesis in a rat model. METHODS: Cell viability, tube formation, and mRNA expression were measured in human umbilical vein endothelial cells treated with deferoxamine. A total of 36 rats were then used for an in vivo study. A dose of 100 mg/kg of deferoxamine was injected subcutaneously into the rat scalp every other day for five treatments. On the day after the final injection, the scalp skin was harvested from half the animals to evaluate the effects of deferoxamine on the recipient site. In the remaining animals, inguinal fat tissue was transplanted to the scalp. Eight weeks after transplantation, the grafts were harvested to evaluate the effects of deferoxamine preconditioning on fat graft survival. RESULTS: In human umbilical vein endothelial cells, treatment with a deferoxamine concentration higher than 400 µM decreased cell viability compared with the control (p = 0.002). Treatment with 100 and 200 µM deferoxamine increased endothelial tube formation (p = 0.001) and mRNA levels of angiogenesis-related factors (p = 0.02). Rat scalps treated with deferoxamine exhibited increased capillary neoformation (p = 0.001) and vascular endothelial growth factor protein expression (p = 0.024) compared with controls. Fat graft volume retention, capillary density (p < 0.001), and adipocyte viability (p < 0.001) in the grafted fat increased when the recipient site was preconditioned with deferoxamine. CONCLUSION: This study demonstrated that recipient site preconditioning with deferoxamine increases fat graft survival by inducing vascular endothelial growth factor and neovascularization.


Assuntos
Tecido Adiposo/transplante , Desferroxamina/farmacologia , Sobrevivência de Enxerto/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Precondicionamento Isquêmico/métodos , Neovascularização Fisiológica/efeitos dos fármacos , Fatores de Crescimento do Endotélio Vascular/biossíntese , Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos , Animais , Humanos , Masculino , Modelos Animais , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular
5.
Br J Anaesth ; 123(5): 584-591, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31521337

RESUMO

BACKGROUND: The REnal Protection Against Ischaemia-Reperfusion in transplantation (REPAIR) RCT examined whether remote ischaemic preconditioning (RIPC) improved renal function after living-donor kidney transplantation. The primary endpoint, glomerular filtration rate (GFR), quantified by iohexol at 12 months, suggested that RIPC may confer longer-term benefit. Here, we present yearly follow-up data of estimated GFR for up to 5 yr after transplantation. METHODS: In this double-blind, factorial RCT, we enrolled 406 adult live donor kidney transplant donor-recipient pairs in 15 European transplant centres. RIPC was performed before induction of anaesthesia. RIPC consisted of four 5 min inflations of a BP cuff on the upper arm to 40 mm Hg above systolic BP separated by 5 min periods of cuff deflation. For sham RIPC, cuff inflation to 40 mm Hg was undertaken. Pairs were randomised to sham RIPC, early RIPC only (immediately pre-surgery), late RIPC only (24 h pre-surgery), or dual RIPC (early and late RIPC). The pre-specified secondary outcome of estimated GFR (eGFR) was calculated from serum creatinine measurements, using the Chronic Kidney Disease Epidemiology Collaboration equation. Predefined safety outcomes were mortality and graft loss. RESULTS: There was a sustained improvement in eGFR after early RIPC, compared with control from 3 months to 5 yr (adjusted mean difference: 4.71 ml min-1 (1.73 m)-2 [95% confidence interval, CI: 1.54-7.89]; P=0.004). Mortality and graft loss were similar between groups (RIPC: 20/205 [9.8%] vs control 24/201 [11.9%]; hazard ratio: 0.79 [95% CI: 0.43-1.43]). CONCLUSIONS: RIPC safely improves long-term kidney function after living-donor renal transplantation when administered before induction of anaesthesia. CLINICAL TRIAL REGISTRATION: ISRCTN30083294.


Assuntos
Precondicionamento Isquêmico/métodos , Transplante de Rim , Traumatismo por Reperfusão/prevenção & controle , Adolescente , Adulto , Idoso , Aloenxertos , Método Duplo-Cego , Europa (Continente) , Feminino , Seguimentos , Taxa de Filtração Glomerular/fisiologia , Humanos , Rim/fisiologia , Rim/cirurgia , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Tempo , Resultado do Tratamento , Adulto Jovem
7.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(7): 601-605, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31537244

RESUMO

Objective To determine whether regulatory T cells (Tregs) are involved in sevoflurane preconditioning-induced brain protection against cerebral ischemia/reperfusion injury. Methods C57BL/6 mice were preconditioned with sevoflurane and then subjected to the middle cerebral artery occlusion modeling. The brain infarct volume and neurological score were assessed at 48 hours after cerebral reperfusion. Meanwhile, the proportion of Tregs in the spleen was analyzed by flow cytometry. Then, CD25 neutralizing antibody was administrated by intraperitoneal injection, following with the analysis of cerebral ischemia/reperfusion injury and the proportion of Tregs in the spleen after sevoflurane preconditioning. Results Compared with a control group, sevoflurane preconditioning markedly mitigated the cerebral ischemia/reperfusion injury in the mice including the infarct volume and neurological score. In the meantime, sevoflurane preconditioning significantly increased the proportion of Tregs in the spleen at 48 hours after cerebral reperfusion. Compared with the isotype antibody group, the CD25 neutralizing antibody reversed the increase of Tregs induced by sevoflurane preconditioning at 48 hours after reperfusion, which was also associated with the reversal of sevoflurane preconditioning-induced protectetion against cerebral ischemia/reperfusion injury. Conclusion Tregs are involved in sevoflurane preconditioning-induced cerebral protection against ischemia/reperfusion injury.


Assuntos
Isquemia Encefálica/prevenção & controle , Precondicionamento Isquêmico , Traumatismo por Reperfusão/prevenção & controle , Sevoflurano/farmacologia , Linfócitos T Reguladores/citologia , Animais , Encéfalo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL
8.
Acta Cir Bras ; 34(7): e201900707, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31531528

RESUMO

PURPOSE: To evaluate the effects of splenic ischemic preconditioning (sIPC) on oxidative stress induced by hepatic ischemia-reperfusion in rats. METHODS: Fifteen male Wistar rats were equally divided into 3 groups: SHAM, IRI and sIPC. Animals from IRI group were subjected to 45 minutes of partial liver ischemia (70%). In the sIPC group, splenic artery was clamped in 2 cycles of 5 min of ischemia and 5 min of reperfusion (20 min total) prior to hepatic ischemia. SHAM group underwent the same surgical procedures as in the remaining groups, but no liver ischemia or sIPC were induced. After 1h, hepatic and splenic tissue samples were harvested for TBARS, CAT, GPx and GSH-Rd measurement. RESULTS: sIPC treatment significantly decreased both hepatic and splenic levels of TBARS when compared to IRI group (p<0.01). Furthermore, the hepatic and splenic activities of CAT, GPx and GSH- Rd were significantly higher in sIPC group than in IRI group. CONCLUSION: sIPC was able to attenuate hepatic and splenic IRI-induced oxidative stress.


Assuntos
Precondicionamento Isquêmico/métodos , Hepatopatias/prevenção & controle , Fígado/irrigação sanguínea , Estresse Oxidativo/fisiologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Fígado/fisiologia , Hepatopatias/fisiopatologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Traumatismo por Reperfusão/fisiopatologia
9.
J Sports Sci ; 37(24): 2798-2805, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31500494

RESUMO

Ischaemic preconditioning (IPC) has emerged as a potential non-invasive ergogenic aid to enhance exercise performance. Repeated application of IPC has demonstrated clinical efficacy, therefore our aims were to investigate its effect on endurance cycling performance and muscle efficiency. Twenty participants undertook 7-d repeated bilateral lower limb occlusion (4 x 5-min) of IPC (220 mmHg) or sham (20 mmHg). Prior to and 72-h following the intervention, participants performed submaximal cycling at 70, 80 and 90% of ventilatory threshold (VT) followed by an incremental exercise test. IPC had no effect on V˙ O2max (P = 0.110); however, time to exhaustion increased by ~ 9% and Wmax by ~ 5 % (IPC pre 307 ± 45 to post 323 ± 51 W) relative to sham (P = 0.002). There were no changes in gross efficiency (GE) (P > 0.05); however, delta efficiency (DE) increased by 3.1% following IPC (P = 0.011). Deoxyhaemoglobin (HHb) was reduced following IPC ~ 30% (P = 0.017) with no change in total haemoglobin (tHb). Repeated IPC over 7-d enhanced muscle efficiency and extended cycling performance. The physiological effects of repeated IPC on skeletal muscle efficiency explains the notable improvements in endurance performance.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Precondicionamento Isquêmico , Músculo Esquelético/fisiologia , Constrição , Estudos Cross-Over , Teste de Esforço , Hemoglobinas/análise , Humanos , Extremidade Inferior , Masculino , Consumo de Oxigênio , Método Simples-Cego , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
10.
Artigo em Russo | MEDLINE | ID: mdl-31407685

RESUMO

AIM: To assess antidepressant properties of remote ischemic limb pre- and post-conditioning. MATERIAL AND METHODS: The study was performed with rats that were subjected to unavoidable aversive stress in the 'learned helplessness' paradigm for developing experimental depression, or were additional exposed to three brief episodes of ischemia/reperfusion of the limb before or after stressing. RESULTS: Remote ischemic preconditioning completely prevented depressive-like behavior and caused hyperactivation of the pituitary-adrenal hormonal axis. Ischemic post-conditioning did not completely correct post-stress hormone dysregulation and animal stress-reactivity. CONCLUSION: Remote ischemic pre- and post-conditioning has a pronounced antidepressant effect and prevents the formation of the main behavioral and endocrine signs of experimental depression.


Assuntos
Depressão , Pós-Condicionamento Isquêmico , Precondicionamento Isquêmico , Traumatismo por Reperfusão Miocárdica , Animais , Depressão/fisiopatologia , Extremidades , Ratos
11.
BMC Neurol ; 19(1): 206, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31443692

RESUMO

BACKGROUND: Subcortical ischemic vascular dementia (SIVD) is very common among the older people, but has no approved treatment. Preclinical trials show that remote ischemic conditioning (RIC) reduces recurrence of ischemic stroke. We hypothesize that RIC may also be an effective therapy for patients with SIVD. METHODS: Thirty-seven consecutive SIVD cases were enrolled in this randomized control study. Eighteen RIC patients underwent five brief cycles of conditioning (bilateral upper limb compression at 200 mmHg) followed by reperfusion twice daily over 6 consecutive months. Nineteen control patients underwent the same process, but at a pressure of 60 mmHg which caused no restriction on the blood flow of the upper limb. The primary outcome measures were changes in neuropsychological assessments. The secondary outcomes included the changes in high-sensitive C-reactive protein (hs-CRP) concentration, white matter lesion volume (WMLV), diffusion tension imaging (DTI) metrics of white matter. All data were collected at baseline and follow-up. RESULTS: A significant treatment difference favoring RIC at 6 months was observed on performance of Hopkins Verbal Learning Test-Revised (HVLT-R), Controlled Oral Word Association Test (COWAT), Trail Making Test A and B (TMT-A & TMT-B), and Judgment of Line Orientation (JLO) (p < 0.05). The control group did not show much improvement after the treatment, and only with a slight change in HVLT-R and TMT-R (p < 0.05). Covariance analysis of efficacy between the two groups suggested that RIC patients performed better on JLO than control patients at the 6-month follow-up (RIC 23.10 vs. control 18.56; p = 0.013). Although DTI metrics were comparable, Hs-CRP levels and WMLV in RIC patients showed a declining trend. CONCLUSIONS: Over the 6-month treatment period, we found that RIC was safe and effective for improving cognitive function in SIVD patients. TRIAL REGISTRATION: Clinical Trial Registration ( http://www.clinicaltrials.gov ), Unique identifier: NCT03022149; Retrospectively registered; Date of registration: January 16, 2017.


Assuntos
Encéfalo/irrigação sanguínea , Cognição , Demência Vascular , Precondicionamento Isquêmico/métodos , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Encéfalo/fisiopatologia , Demência Vascular/patologia , Demência Vascular/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Extremidade Superior/fisiopatologia
12.
Rev Cardiovasc Med ; 20(2): 59-71, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31344998

RESUMO

Remote ischemic conditioning of the heart (including pre-, per-, and post-conditioning) is a phenomenon where short episodes of non-lethal ischemia in the distant vessels within the heart or distant organs from the heart protects the myocardium against sustained ischemia/reperfusion injury. Several pathways have been proposed to be involved in the mechanisms of Remote ischemic conditioning. While triggers of Remote ischemic conditioning act in preconditioned areas, its mediators transduce protective signals via humoral or neuronal pathways to the heart. Remote ischemic conditioning is mediated via receptor and nonreceptor signaling through secondary mediators, which transfer the signal within the cardiomyocyte and activate cardioprotective pathways that lead to higher resistance of the heart to ischemia/reperfusion. Apparently, identification of endogenous signal molecules involved in the mechanisms of Remote ischemic conditioning have therapeutic implications in the management of patients suffering from myocardial ischemia through the development of diverse beneficial effects. Recently, different non-coding RNAs such as microRNAs or long non-coding RNAs have been identified as emerging factors that trigger protective mechanisms in the heart. These non-coding RNAs are transferred to the heart via extracellular vesicles that exert remote cardioprotection. This review is intended to summarize the existing knowledge about the potential role of extracellular vesicles as humoral transmitters of Remote ischemic conditioning and emphasize the involvement of non-coding RNAs in the mechanism of cardioprotection by Remote ischemic conditioning.


Assuntos
Vesículas Extracelulares/metabolismo , Pós-Condicionamento Isquêmico/métodos , Precondicionamento Isquêmico/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , RNA não Traduzido/metabolismo , Animais , Vesículas Extracelulares/genética , Vesículas Extracelulares/patologia , Regulação da Expressão Gênica , Humanos , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , RNA não Traduzido/genética , Transdução de Sinais
13.
Graefes Arch Clin Exp Ophthalmol ; 257(10): 2095-2101, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31273510

RESUMO

PURPOSE: Remote ischemic conditioning (RIC) implies that transient ischemia in one organ can affect blood flow and protect from ischemia in another remote organ such as the retina. The purpose of the present study was to investigate the effect of RIC on the diameter of retinal arterioles in patients with diabetic retinopathy and whether this effect differs among peripheral and macular vessels. METHODS: In twenty type 1 diabetes patients aged 20-31 years, the Dynamic Vessel Analyzer (DVA) was used to measure diameters of peripheral and macular arterioles during rest, isometric exercise, and flicker stimulation. Measurements were obtained before, immediately after, and 1 h after RIC, and were compared to responses obtained from normal persons. RESULTS: The reduced baseline diameter (p < 0.009) and contraction of peripheral retinal arterioles during isometric exercise (p = 0.025) observed immediately after RIC in normal persons were absent in the studied diabetic patients. CONCLUSIONS: RIC affects the diameter of peripheral but not macular arterioles in normal persons, but the response is abolished in diabetic patients. TRIAL REGISTRATION: NCT03906383.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Retinopatia Diabética/diagnóstico , Isquemia/diagnóstico , Fluxo Sanguíneo Regional/fisiologia , Artéria Retiniana/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Vasodilatação/fisiologia , Adulto , Arteríolas/patologia , Arteríolas/fisiopatologia , Retinopatia Diabética/complicações , Retinopatia Diabética/fisiopatologia , Feminino , Humanos , Isquemia/etiologia , Isquemia/fisiopatologia , Precondicionamento Isquêmico/métodos , Masculino , Artéria Retiniana/fisiopatologia , Adulto Jovem
14.
Acta Histochem ; 121(6): 732-741, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31270014

RESUMO

The aim of this study was to investigate neuroprotective effect of bradykinin postconditioning on the rabbit spinal cord after 20 min of ischemia and 3 days of reperfusion. Bradykinin was administered by single i.p. application at 1, 6, 12 or 24 h after ischemia. Assessment of neurological function of hind limbs (Tarlov score) was estimated. Quantitative analysis was evaluated by Fluoro Jade B method, NeuN and ubiquitin immunohistochemistry in anterior horn neurons of the spinal cord. Histomorphologically distribution of ubiquitin and endogenous antioxidant enzymes (SOD1, SOD2, catalase) immunoreaction was described. Bradykinin postconditioning showed decreased number of degenerated neurons, increased number of surviving neurons and increase in number of ubiquitin positive neurons in all bradykinin postconditioned groups versus ischemia/reperfusion group. According to our results bradykinin postconditioning applied 24 h after ischemia significantly decreased (p < 0.001) number of degenerated neurons versus ischemia/reperfusion group. The least effective time window for bradykinin postconditioning was at 12 h after ischemia. Tarlov score was significantly improved (p < 0.05) in groups with bradykinin postconditioning applied 1, 6 or 24 h after ischemia versus ischemia/reperfusion group. Tarlov score in group with bradykinin application 12 h after ischemia was significantly decreased (p < 0.05) versus sham control group. Neuronal immunoreaction of ubiquitin, SOD1, SOD2 and catalase influenced by bradykinin postconditioning was dependent on neuronal survival or degeneration. In conclusion, bradykinin postconditioning showed protective effect on neurons in anterior horns of the rabbit spinal cord and improved motor function of hind limbs.


Assuntos
Antioxidantes/metabolismo , Bradicinina/farmacologia , Catalase/metabolismo , Precondicionamento Isquêmico , Neuroproteção/efeitos dos fármacos , Medula Espinal/enzimologia , Superóxido Dismutase-1/metabolismo , Superóxido Dismutase/metabolismo , Ubiquitina/metabolismo , Animais , Masculino , Neurônios/enzimologia , Neurônios/patologia , Coelhos , Medula Espinal/patologia
15.
Chem Biol Interact ; 310: 108738, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31283913

RESUMO

Ischemic stroke and reperfusion injury are a common and serve medical situation in the elderly population. H2S is a gas neuromodulator which also possesses anti-oxidant and anti-inflammatory properties, and is found to play neuroprotective effect in neurodegenerative diseases. This study investigated the effect of endogenous and exogenous H2S in a mouse model of ischemic stroke. 129P2-Cbstm1Unc/J mice with heterozygous mutants in H2S generating enzyme cystathionine ß-synthase were used to study the effect of endogenous H2S. H2S donor NaHS was used as exogenous H2S. Animals were pretreated with H2S and then subjected to middle cerebral artery occlusion surgery. Behavioral outcome was evaluated by novel object recognition test. Inflammatory cytokines were measured using ELISA. Western blot was used to detect the activation of NF-κB. Aged 129P2-Cbstm1Unc/J mice showed exaggerated inflammation and more severe cognitive impairment after ischemia, while exogenous H2S treatment inhibited inflammation and attenuated behavioral impairment. The anti-inflammatory effect of H2S was mediated by inhibiting NF-κB. Our findings suggest that both endogenous and exogenous H2S are involved in the neuroprotection against ischemia/reperfusion-induced cerebral injury.


Assuntos
Sulfeto de Hidrogênio/uso terapêutico , Precondicionamento Isquêmico/métodos , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Comportamento Animal/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Citocinas/metabolismo , Sulfeto de Hidrogênio/farmacologia , Infarto da Artéria Cerebral Média/complicações , Inflamação/tratamento farmacológico , Camundongos , NF-kappa B/metabolismo , Traumatismo por Reperfusão/prevenção & controle
16.
Mol Med Rep ; 20(2): 1837-1845, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257533

RESUMO

Hypoxic preconditioning (HPC) is neuroprotective against ischaemic brain injury; however, the roles of potential anti­apoptotic signals in this process have not been assessed. To elucidate the molecular mechanisms involved in HPC­induced neuroprotection, the effects of HPC on the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA)/cAMP response element­binding protein (CREB) signalling pathway and apoptosis in Sprague­Dawley pups (postnatal day 7) treated with propofol were investigated. Western blot and histological analyses demonstrated that HPC exerts multiple effects on the hippocampus, including the upregulation of cAMP and phosphorylation of CREB. These effects were partially blocked by intracerebroventricular injection of the protein kinase antagonist H89 (5 µmol/5 µl). Notably, the level of cleaved caspase­3 was significantly downregulated by treatment with the cAMP agonist Sp­cAMP (20 nmol/5 µl). The results indicate that propofol increased the level of cleaved caspase­3 and Bax by suppressing the activity of cAMP­dependent proteins and Bcl­2; thus, HPC prevents propofol from triggering apoptosis via the cAMP/PKA/CREB signalling pathway.


Assuntos
Lesões Encefálicas/terapia , Precondicionamento Isquêmico/métodos , Neurônios/metabolismo , Neuroproteção/genética , Animais , Animais Recém-Nascidos , Apoptose/genética , Lesões Encefálicas/genética , Lesões Encefálicas/patologia , Lesões Encefálicas/prevenção & controle , AMP Cíclico , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/genética , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Neurônios/patologia , Fosforilação/genética , Propofol/toxicidade , Ratos , Transdução de Sinais/genética , Lobo Temporal/metabolismo , Lobo Temporal/patologia
17.
J Pineal Res ; 67(2): e12589, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31155748

RESUMO

It has been found that remote organ/limb temporary ischemia, known as remote ischemic conditioning, can provide protection against the formation of lethal ischemic outcome. Current evidence suggests that aging and age-releated comorbidities impair the cardioprotective effects of conditionings. In conjuction with aging, decrease in melatonin synthesis from pineal gland can have role in the pathogenesis of aging and age-related cardiovascular diseases. In this study, we investigated the effects of remote ischemic perconditioning (RIPerC) and physiological and pharmacological concentrations of melatonin on the infarct size, Fas gene, cytochrome b-245 beta chain (Cybb) gene, nuclear factor-kappa B (NfκB), and irisin using an in vivo model of myocardial ischemia/reperfusion (I/R) injury. Sprague-Dawley rats that were divided into two groups first as non-pinealectomized (Non-Px) and pinealectomized (Px), and then (a) Control; (b) I/R (30-minute ischemia, 120-minute reperfusion caused by left coronary artery ligation); (c) I/R + RIPerC (when myocardial ischemia initiated, three cycles of 5-minute occlusion followed by 5-minute reperfusion); (d) I/R + Mel; (e) Px; (f) Px + I/R; (g) Px + I/R + RIPerC; (h) Px + I/R + RIPerC + Mel groups. The infarct size was determined by TTC staining and analyzed by the ImageJ program. Molecular parameters were evaluated by qRT-PCR and Western blot. Results showed that increased infarct size in Non-Px groups decreased with RIPerC and melatonin. However, increased infarct size in Px groups was decreased minimally with RIPerC and significantly decreased with RIPerC + Melatonin. Fold change in Fas gene was associated with the infarct size. RIPerC and melatonin reduced expressions of Cybb, NfκB, and irisin genes. The physiological release and pharmacological concentration of melatonin may improve protective effect of RIPerC against I/R-induced infarct size by modulating Cybb, Fas, NfκB, Irisin signaling pathways.


Assuntos
Fibronectinas/metabolismo , Precondicionamento Isquêmico , Melatonina/farmacologia , Traumatismo por Reperfusão Miocárdica/metabolismo , NADPH Oxidase 2/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor fas/metabolismo , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Ratos Sprague-Dawley
18.
Scand Cardiovasc J ; 53(4): 192-196, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31169413

RESUMO

Objectives. The hypothermic circulatory arrest (HCA) is still of paramount importance in aortic arch surgery, but the safe period of the arrest is limited. Remote ischaemic preconditioning (RIPC) prepares the cerebral tissue for ischaemic insult. Prolongation of the permissible period of HCA with RIPC may have a major impact on the outcome of aortic operations requiring cessation of blood flow by decreasing the rate of neurological deficits. Design. Twenty pigs were randomised into the RIPC group (n = 10) and the control group (n = 10). The RIPC group underwent four cycles of transient hind limb ischaemia. Both groups underwent cooling with cardiopulmonary bypass to 11 °C followed by a 45-minute HCA and re-warming to 36 °C. Cerebral blood flow was measured with a transit time ultrasonic flowmeter from the right common carotid artery, and the arteriovenous oxygen difference was calculated from sagittal sinus and arterial blood samples. Measurements were taken at several time points during cooling and warming. Temperature coefficient (Q10) was calculated to determine estimated permissible periods of HCA. Results. The Q10 was 2.27 (1.98-2.58) for the RIPC group and 1.87 (1.61-2.25) for the control group. The permissible period of HCA at 18 °C was 26 minutes (20-33) in the RIPC group and 17 minutes (13-25) in the control group (p = .063)(Data expressed in medians and interquartile ranges). Conclusions. RIPC tends to suppress cerebral metabolism during cooling with cardiopulmonary bypass and may prolong estimated permissible period of HCA.


Assuntos
Encéfalo/irrigação sanguínea , Parada Circulatória Induzida por Hipotermia Profunda , Membro Posterior/irrigação sanguínea , Hipóxia Encefálica/prevenção & controle , Precondicionamento Isquêmico/métodos , Traumatismo por Reperfusão/prevenção & controle , Animais , Velocidade do Fluxo Sanguíneo , Encéfalo/metabolismo , Circulação Cerebrovascular , Parada Circulatória Induzida por Hipotermia Profunda/efeitos adversos , Metabolismo Energético , Feminino , Hipóxia Encefálica/etiologia , Hipóxia Encefálica/metabolismo , Hipóxia Encefálica/fisiopatologia , Precondicionamento Isquêmico/efeitos adversos , Duração da Cirurgia , Fluxo Sanguíneo Regional , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Fatores de Risco , Sus scrofa , Fatores de Tempo
19.
Acta Cir Bras ; 34(5): e201900501, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166464

RESUMO

PURPOSE: To analyze the effects of ischemic preconditioning (IPC) in the expression of apoptosis-related genes in rat small intestine subjected to ischemia and reperfusion. METHODS: Thirty anesthetized rats underwent laparotomy and were drive into five groups: control (CG); ischemia (IG); ischemia and reperfusion (IRG); IPC and ischemia (IG+IPC); IPC and ischemia and reperfusion (I/RG+IPC). Intestinal ischemia was performed by clamping the superior mesenteric artery for 60 minutes, whereas reperfusion lasted for 120 minutes. IPC was carried out by one cycle of 5 minutes of ischemia followed by 10 minutes of reperfusion prior to the prolonged 60-minutes-ischemia and 120-minutes-reperfusion. Thereafter, the rats were euthanized and samples of small intestine were processed for histology and gene expression. RESULTS: Histology of myenteric plexus showed a higher presence of neurons presenting pyknotic nuclei and condensed chromatin in the IG and IRG. IG+IPC and I/RG+IPC groups exhibited neurons with preserved volume and nuclei, along with significant up-regulation of the anti-apoptotic protein Bcl2l1 and down-regulation of pro-apoptotic genes. Moreover, Bax/Bcl2 ratio was lower in the groups subjected to IPC, indicating a protective effect of IPC against apoptosis. CONCLUSION: Ischemic preconditioning protect rat small intestine against ischemia/reperfusion injury, reducing morphologic lesions and apoptosis.


Assuntos
Proteínas Reguladoras de Apoptose/análise , Apoptose/genética , Precondicionamento Isquêmico/métodos , Jejuno/irrigação sanguínea , Jejuno/patologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Proteínas Reguladoras de Apoptose/genética , Constrição , Regulação para Baixo , Células Endoteliais/patologia , Expressão Gênica , Masculino , Artéria Mesentérica Superior , Isquemia Mesentérica/genética , Isquemia Mesentérica/patologia , Distribuição Aleatória , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Reprodutibilidade dos Testes
20.
Ann Vasc Surg ; 60: 246-253, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31200043

RESUMO

BACKGROUND: While the perioperative stroke rate after carotid endarterectomy (CEA) is low, "silent" microinfarctions identified by magnetic resonance imaging (MRI) are common and have been correlated with postoperative neurocognitive decline. Our study will investigate the role of remote ischemic preconditioning (RIPC) as a potential neuroprotective mechanism. RIPC is a well-tolerated stimulus that, through neuronal and humoral pathways, generates a systemic environment of greater resistance to subsequent ischemic insults. We hypothesized that patients undergoing RIPC before CEA will have improved postoperative neurocognitive scores compared with those of patients undergoing standard care. METHODS: Patients undergoing CEA will be randomized 1:1 to RIPC or standard clinical care. Those randomized to RIPC will undergo a standard protocol of 4 cycles of RIPC. Each RIPC cycle will involve 5 min of forearm ischemia with 5 min of reperfusion. Forearm ischemia will be induced by a blood pressure cuff inflated to 200 mm Hg or at least 15 mm Hg higher than the systolic pressure if it is >185 mm Hg. This will occur after anesthesia induction and during incision/dissection but before manipulation or clamping of the carotid; thus, patients will be blinded to their assignment. Before carotid endarterectomy, all patients will undergo baseline neurocognitive testing in the form of a Montreal Cognitive Assessment (MoCA) and National Institutes of Health (NIH) Toolbox. MoCA testing only will be conducted on postoperative day 1 in the hospital. The full neurocognitive testing battery will again be conducted at 1-month follow-up in the office. Changes from baseline will be compared between arms at the follow-up time points. Assuming no drop-ins or dropouts and a 10% loss to follow-up, we would need a sample size of 43 patients for 80% power per treatment arm. The primary endpoint, change in MoCA scores, will be analyzed using a random effects model, and secondary outcomes will be analyzed using either linear or logistic regression where appropriate. CONCLUSIONS: RIPC, if shown to be effective in protecting patients from neurocognitive decline after CEA, represents a safe, inexpensive, and easily implementable method of neuroprotection.


Assuntos
Estenose das Carótidas/cirurgia , Transtornos Cerebrovasculares/prevenção & controle , Endarterectomia das Carótidas/efeitos adversos , Antebraço/irrigação sanguínea , Precondicionamento Isquêmico/métodos , Oclusão Terapêutica/métodos , Idoso , Idoso de 80 Anos ou mais , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Transtornos Cerebrovasculares/etiologia , Feminino , Humanos , Precondicionamento Isquêmico/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fatores de Proteção , Ensaios Clínicos Controlados Aleatórios como Assunto , Fluxo Sanguíneo Regional , Fatores de Risco , Método Simples-Cego , Oclusão Terapêutica/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
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