scholarly journals Diazoxide Attenuates Postresuscitation Brain Injury in a Rat Model of Asphyxial Cardiac Arrest by Opening Mitochondrial ATP-Sensitive Potassium Channels

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Haidong Wu ◽  
Peng Wang ◽  
Yi Li ◽  
Manhui Wu ◽  
Jiali Lin ◽  
...  

Objective. We investigated whether and how diazoxide can attenuate brain injury after cardiopulmonary resuscitation (CPR) by selective opening of mitochondrial ATP-sensitive potassium (mitoKATP) channels.Methods. Adult male Sprague-Dawley rats with induced cerebral ischemia (n=10per group) received an intraperitoneal injection of 0.1% dimethyl sulfoxide (1 mL; vehicle group), diazoxide (10 mg/kg; DZ group), or diazoxide (10 mg/kg) plus 5-hydroxydecanoate (5 mg/kg; DZ + 5-HD group) 30 min after CPR. The control group (sham group,n=5) underwent sham operation, without cardiac arrest. Mitochondrial respiratory control rate (RCR) was determined. Brain cell apoptosis was assessed using TUNEL staining. Expression of Bcl-2, Bax, and protein kinase C epsilon (PKCε) in the cerebral cortex was determined by Western blotting and immunohistochemistry.Results. The neurological deficit scores (NDS) in the vehicle group decreased significantly at 24 h and 48 h after CPR. Diazoxide significantly improved NDS and mitochondrial RCR after CPR at both time points; 5-HD cotreatment abolished these effects. Diazoxide decreased TUNEL-positive cells following CPR, upregulated Bcl-2 and PKCε, downregulated Bax, and increased the Bcl-2/Bax ratio; 5-HD cotreatment reversed these effects.Conclusions. Diazoxide attenuates postresuscitation brain injury, protects mitochondrial function, inhibits brain cell apoptosis, and activates the PKC pathway by opening mitoKATP channels.

2016 ◽  
Vol 40 (3-4) ◽  
pp. 621-632 ◽  
Author(s):  
Qing Zhao ◽  
Jianyong Yin ◽  
Zeyuan Lu ◽  
Yiwei Kong ◽  
Guangyuan Zhang ◽  
...  

Background: Sulodexide is a powerful antithrombin agent with reno-protective property. However, whether it has beneficial effects on Contrast-Induced Nephropathy (CIN) remained elusive. In the current study, we evaluated the therapeutic effects of Sulodexide on CIN and investigated the potential mechanisms. Methods: CIN model was induced by intravenous injection of indomethacin, followed by Ioversol and L-NAME. Sprague-Dawley rats were divided into 4 groups: control group, CIN group, CIN+vehicle group (CIN rats pretreated with vehicle) and CIN+ Sulodexide (CIN rats pretreated with Sulodexide). Sulodexide or an equivalent volume of vehicle was intravenously delivered 30 min before the induction of CIN. All the animals were sacrificed at 24h after CIN and tissues were harvested to evaluate renal injury, kidney oxidative stress and apoptosis levels. Plasma antithrombin III (ATIII) activities were also measured. Results: Compared to the untreated CIN group, improved renal function, reduced tubular injury, decreased levels of oxidative stress and apoptosis were observed in CIN rats receiving Sulodexide injection. In addition, we also found that ATIII activity was significantly higher in Sulodexide-administered group than that in vehicle-injected CIN rats. For in vitro studies, HK2 cells were exposed to Ioversol and the cyto-protective effects of Sulodexide were also determined. Sulodexide pretreatment protected HK2 cells against the cytotoxicity of Ioversol via inhibiting caspase-3 activity. Preincubation with Sulodexide could also attenuate H2O2-induced increases in ROS, apoptosis and caspase-3 levels. Conclusions: Taken together, Sulodexide could protect against CIN through activating ATIII, and inhibiting oxidative stress, inflammation and apoptosis.


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Aiming Wu ◽  
Jianying Zhai ◽  
Dongmei Zhang ◽  
Lixia Lou ◽  
Haiyan Zhu ◽  
...  

Aim. To determine the effect of a Chinese herbal compound named Wenxin Granule on ventricular remodeling and myocardial apoptosis in rats with myocardial infarction (MI).Methods. Male Sprague-Dawley (SD) rats were randomly divided into four groups: the control group, the model group, the metoprolol group, and the Wenxin Granule group (WXKL group) with sample size (n) of 7 rats in each group. An MI model was established in all rats by occlusion of the left anterior descending coronary artery (the control group was without occlusion). Wenxin Granule (1.35 g/kg/day), metoprolol (12 mg/kg/day), and distilled water (5 mL/kg/day for the control and model groups) were administered orally for 4 weeks. Ultrasonic echocardiography was used to examine cardiac structural and functional parameters. Myocardial histopathological changes were observed using haematoxylin and eosin (H&E) dyeing. Myocardial apoptosis was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) staining. Serum angiotensin II (Ang II) concentration was measured using the enzyme-linked immunosorbent assay (ELISA).Results. It was found that Wenxin Granule could partially reverse ventricular remodeling, improve heart function, alleviate the histopathological damage, inhibit myocardial apoptosis, and reduce Ang II concentration in rats with MI.Conclusions. The results of the current study suggest that Wenxin Granule may be a potential alternative and complementary medicine for the treatment of MI.


2020 ◽  
Vol 8 (A) ◽  
pp. 837-840
Author(s):  
Andre Marolop Pangihutan Siahaan ◽  
Rr Suzy Indharty ◽  
Jessy Chrestella ◽  
Wismaji Sadewo ◽  
Steven Tandean ◽  
...  

BACKGROUND: Repetitive traumatic brain injury (TBI), even without acute sequela, can induce a delayed neurodegenerative with overexpression of phosphorylated tau (p-tau) as hallmark, caused by chronic inflammation mediated in part by microglial activation. AIM: The aim of this study was to examine the dynamics of p-tau accumulation and microglial activation following repetitive TBI. MATERIALS AND METHODS: Thirty Sprague–Dawley rats were randomized into a sham control group and two treatment groups receiving three successive closed-skull impacts (TBI model) from a 40-g mass dropped from a 1-m height on alternating days (days 0, 1, 3, and 7). The first treatment group was sacrificed on the last day of trauma and the second treatment group after 7 days of no trauma. The expression level of p-tau was evaluated by AT-8 antibody immunostaining and microglial activation by anti-CD-68 immunostaining. RESULTS: Immunoexpression of AT-8 was significantly elevated 7 days after TBI compared to the last day of trauma and compared to the sham control group, while CD-68 expression was significantly higher than sham controls on the last day of trauma and remained elevated for 7 days without trauma. CONCLUSION: The study showed that brain trauma can induce p-tau overexpression and microglial activation that is sustained during the non-trauma period.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Jiangfeng Liu ◽  
Huijun Kang ◽  
Jiangfeng Lu ◽  
Yike Dai ◽  
Fei Wang

Abstract Background Poor osseointegration is the key reason for implant failure after arthroplasty,whether under osteoporotic or normal bone conditions. To date, osseointegration remains a major challenge. Recent studies have shown that deferoxamine (DFO) can accelerate osteogenesis by activating the hypoxia signaling pathway. The purpose of this study was to test the following hypothesis: after knee replacement, intra-articular injection of DFO will promote osteogenesis and osseointegration with a 3D printed titanium prosthesis in the bones of osteoporotic rats. Materials and methods Ninety female Sprague–Dawley rats were used for the experiment. Ten rats were used to confirm the successful establishment of the osteoporosis model: five rats in the sham operation group and five rats in the ovariectomy group. After ovariectomy and knee arthroplasty were performed, the remaining 80 rats were randomly divided into DFO and control groups (n = 40 per group). The two groups were treated by intraarticular injection of DFO and saline respectively. After 2 weeks, polymerase chain reaction (PCR) and immunohistochemistry were used to evaluate the levels of HIF-1a, VEGF, and CD31. HIF-1a and VEGF have been shown to promote angiogenesis and bone regeneration, and CD31 is an important marker of angiogenesis. After 12 weeks, the specimens were examined by micro-computed tomography (micro-CT), biomechanics, and histopathology to evaluate osteogenesis and osseointegration. Results The results of PCR showed that the mRNA levels of VEGF and CD31 in the DFO group were significantly higher than those in the control group. The immunohistochemistry results indicated that positive cell expression of HIF-1a, VEGF, and CD31 in the DFO group was also higher. Compared with the control group, the micro-CT parameters of BMD, BV/TV, TB. N, and TB. Th were significantly higher. The maximal pull-out force and the bone-to-implant contact value were also higher. Conclusions The local administration of DFO, which is used to activate the HIF-1a signaling pathway, can promote osteogenesis and osseointegration with a prosthesis in osteoporotic bone.


Author(s):  
Jun-Li Zhao ◽  
Ting Zhang ◽  
Xia Shao ◽  
Jun-Jun Zhu ◽  
Mei-Zi Guo

Abstract Background Peritoneal fibrosis (PF) remains a serious complication of long-term peritoneal dialysis (PD). The goal of this study was to investigate the anti-fibrotic effects of curcumin on the PF response to PD and its’ mechanism. Methods Male Sprague–Dawley rats were infused with 20 mL of 4.25% glucose-based standard PD fluid for 8 consecutive weeks to establish PF model and then divided into five groups: Control, received sham operation and 0.9% physiological saline; PD, received 4.25% standard PD fluid; Curcumin, PD rats injected intraperitoeally with curcumin for 8 weeks at doses of 10, 20 or 40 mg/kg. Masson’s staining was performed to evaluate the extent of PF. Peritoneal Equilibration Test (PET) was conducted to assess ultrafiltration volume (UFV) and mass transfer of glucose (MTG), quantitative RT-PCR, and immunohistochemistry or western blotting were performed to measure the expression levels of inflammation and fibrosis-associated factors. We also detected the TGF-β1 in peritoneal fluid by ELISA. Results Compared with the control group, the PD rats showed decreased UFV (2.54 ± 0.48 to 9.87 ± 0.78 mL, p < 0.05] and increased MTG (18.99 ± 0.86 to 10.85 ± 0.65 mmol/kg, p < 0.05) as well as obvious fibroproliferative response, with markedly increased peritoneal thickness (178.33 ± 4.42 to 25.26 ± 0.32um, p < 0.05) and higher expression of a-SMA, collagen I and TGF-β1. Treatment with curcumin significantly increased UFV, reduced MTG and peritoneal thickness of PD rats. The elevated TGF-β1 in peritoneal fluid of PD rats was significantly decreased by curcumin. It attenuated the increase in protein and mRNA of TGF-β1, α-SMA and collagen I in peritoneum of PD rats. The mRNA expressions of TAK1, JNK and p38, as well as the protein expressions of p-TAK1, p-JNK and p-p38 in peritoneum of PD rats were reduced by curcumin. Conclusions Present results demonstrate that curcumin showed a protective effect on PD-related PF and suggest an implication of TAK1, p38 and JNK pathway in mediating the benefical effects of curcumin.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Kyung-Jin Oh ◽  
Hyun-Suk Lee ◽  
Kyuyoun Ahn ◽  
Kwangsung Park

Background. The objectives of this study were to investigate the localization of tight junctions and the modulation of zonula occludens- (ZO-) 1, occludin and claudin-1 expression by estrogen in castrated female rat vagina. Female Sprague-Dawley rats (230–240 g,n=45) were divided into three groups and subjected to a sham operation (control group,n=15), bilateral ovariectomy (Ovx group,n=15), or bilateral ovariectomy followed by daily subcutaneous injection of 17β-estradiol (50 μg/kg/day, Ovx + Est group,n=15). The cellular localization and expression of ZO-1, occludin, and claudin-1 were determined in each group by immunohistochemistry and western blot.Results. Expression of ZO-1 was diffuse in all groups, with the highest intensity in the superficial epithelium in the control group. Occludin was localized in the intermediate and basal epithelium. Claudin-1 was most intense in the superficial layer of the vaginal epithelium in the control group. Expression of ZO-1, occludin, and claudin-1 was significantly decreased after ovariectomy and was restored to the level of the control after estrogen replacement.Conclusions. Tight junctions are distinctly localized in rat vagina, and estrogen modulates the expression of tight junctions. Further researches are needed to clarify the functional role of tight junctions in vaginal lubrication.


2019 ◽  
Author(s):  
Jie Guo ◽  
Xiaolu Cao ◽  
Xianmin Hu ◽  
Shulan Li ◽  
Jun Wang

Abstract Background: As a chemical extensively used in industrial areas as well as formed during heating of carbohydrate-rich food and tobacco, acrylamide (ACR) has been known as well-established neurotoxic pollutant. Although the precise mechanism is unclear, enhanced apoptosis, oxidative stress and inflammation have been demonstrated to contribute to the ACR-induced neurotoxicity. In this study, we assessed the possible anti-apoptotic, antioxidant and anti-inflammatory effects of curcumin, the most active component in a popular spice known as turmeric, on the neurotoxicity caused by ACR in rats. Methods: Curcumin at the dose of 50 and 100 mg/kg was orally given to ACR- intoxicated Sprague-Dawley rats exposed by ACR at 40mg/kg for 4 weeks. All rats were subjected to behavioral analysis. The HE staining and terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (TUNEL) staining were used to detect histopathological changes and apoptotic cells, respectively. The mRNA and protein expressions of apoptosis-related molecule telomerase reverse transcriptase (TERT) were detected using real-time PCR and immunohistochemistry, respectively. The contents of malondialdehyde (MDA) and glutathione (GSH) as well as the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured as the indicators for evaluating the level of oxidative stress in brain. The levels of pro-inflammatory cytokinestumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in cerebral homogenates were detected using ELISA assay. Results: Concurrent administration of curcumin at the oral doses of 50 and 100 mg/kg with ACR significantly protected the rats from ACR-induced weigh loss and motor function deficits, and improved the pathological alterations in the ACR-intoxicated brains. Curcumin treatment especially at a high dose enhanced the TERT mRNA expression level and increased the number of TERT-positive nerve cells in cortex tissues of ACR intoxicated rats. The levels of MDA, TNF-α and IL-1β in the cerebral homogenates were reduced, the contents of GSH as well as the activities of SOD and GSH-Px were increased by curcumin treatment, compared to ACR control group. Conclusions: These data suggested the anti-apoptotic, antioxidant and anti-inflammatory effects of curcumin on ACR-induced neurotoxicity in rats. And maintaining TERT-related anti-apoptotic function might be one mechanism underlying the protective effect of curcumin on ACR-intoxicated brains.


Antibodies ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 51
Author(s):  
Ellinor I. Peerschke ◽  
Elisa de Stanchina ◽  
Qing Chang ◽  
Katia Manova-Todorova ◽  
Afsar Barlas ◽  
...  

gC1qR is highly expressed in breast cancer and plays a role in cancer cell proliferation. This study explored therapy with gC1qR monoclonal antibody 60.11, directed against the C1q binding domain of gC1qR, in a murine orthotopic xenotransplant model of triple negative breast cancer. MDA231 breast cancer cells were injected into the mammary fat pad of athymic nu/nu female mice. Mice were segregated into three groups (n = 5, each) and treated with the vehicle (group 1) or gC1qR antibody 60.11 (100 mg/kg) twice weekly, starting at day 3 post-implantation (group 2) or when the tumor volume reached 100 mm3 (group 3). At study termination (d = 35), the average tumor volume in the control group measured 895 ± 143 mm3, compared to 401 ± 48 mm3 and 701 ± 100 mm3 in groups 2 and 3, respectively (p < 0.05). Immunohistochemical staining of excised tumors revealed increased apoptosis (caspase 3 and TUNEL staining) in 60.11-treated mice compared to controls, and decreased angiogenesis (CD31 staining). Slightly decreased white blood cell counts were noted in 60.11-treated mice. Otherwise, no overt toxicities were observed. These data are the first to demonstrate an in vivo anti-tumor effect of 60.11 therapy in a mouse model of triple negative breast cancer.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Guangqian Li ◽  
LeiQian ◽  
Pan Gu ◽  
Dan Fan

Abstract Background Neuroprotection strategies after cardiac arrest (CA)/cardiopulmonary resuscitation (CPR) remain key areas of basic and clinical research. This study was designed to investigate the neuroprotective effects of dexmedetomidine following resuscitation and potential mechanisms. Methods Anesthetized rats underwent 6-min asphyxia-based cardiac arrest and resuscitation, after which the experimental group received a single intravenous dose of dexmedetomidine (25 μg/kg). Neurological outcomes and ataxia were assessed after the return of spontaneous circulation. The serum levels and brain expression of inflammation markers was examined, and apoptotic cells were quantified by TUNEL staining. Results Neuroprotection was enhanced by dexmedetomidine post-conditioning after the return of spontaneous circulation. This enhancement was characterized by the promotion of neurological function scores and coordination. In addition, dexmedetomidine post-conditioning attenuated the serum levels of the pro-inflammatory cytokine tumor necrosis factor (TNF)-α at 2 h, as well as interleukin IL-1β at 2, 24, and 48 h. TUNEL staining showed that the number of apoptotic cells in the dexmedetomidine post-conditioning group was significantly reduced compared with the control group. Further western blot analysis indicated that dexmedetomidine markedly reduced the levels of caspase-3 and nuclear factor-kappa B (NF-κB) in the brain. Conclusions Dexmedetomidine post-conditioning had a neuroprotective effect against cerebral injury following asphyxia-induced cardiac arrest. The mechanism was associated with the downregulation of apoptosis and neuroinflammation.


2019 ◽  
Author(s):  
Chunlin Xing ◽  
Yang Chen ◽  
Xuemei Zhu ◽  
Guoping Lu ◽  
Weiming Chen

AbstractCardiac arrest (CA) is a prominent cause of mortality worldwide. A large number of patients after post-cardiac arrest is often associated with a phase of impaired immunity. Through an asphyxial cardiac arrest rat model, we investigate the peripheral blood T cells subsets and the expressions of surface molecules after restoration of spontaneous circulation (ROSC). Sprague-Dawley rats (weight, 300-400 g) were randomly divided into cardiac arrest (CA) group and sham-operated group. CA group rats were induced by 6 minutes of asphyxia. After successful ROSC, 24 surviving rats in two groups were randomly assigned to be sacrificed (n = 8 per subgroup) at 3, 24 and 72 h. The proportion of T cells and CD4+, CD8+ subsets as well as the expression of surface molecules (CTLA-4, PD-1, CD28) on T cells were identified by flow cytometry. The protein concentrations of cytokines (TNF-α, IL-6, IL-10, IL-4, IFN-γ, IL-17A) in serum were measured by ELISA. Compared with sham-operated control group, CD3+ lymphocytes in CA group were significantly decreased at 24 and 72 h post-ROSC. The expression levels of CD28, PD-1, and CTLA-4 on T cells were markedly increased in CA groups at 24 h post-ROSC. Additionally, the concentrations of IFN-γ were significantly declined, while IL-4 was markedly elevated in the CA group at 24 and 72 h post-ROSC. T cells function is moderately changed after CA, which is associated with decreased percentage of T cells, the upregulation of co-inhibitory molecules, and the shift from T helper (Th) 1 to Th2.


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