Effects of Gingko biloba Extract on Gap Junction Changes Induced by Reperfusion/Reoxygenation After Ischemia/Hypoxia in Rat Brain

2005 ◽  
Vol 33 (06) ◽  
pp. 923-934 ◽  
Author(s):  
Zhen Li ◽  
Xian-Ming Lin ◽  
Pei-Li Gong ◽  
Fan-Dian Zeng ◽  
Guan-Hua Du
Keyword(s):  
Protein Expression ◽  
Gap Junction ◽  
Neurological Deficit ◽  
Ischemia Reperfusion ◽  
Cx43 Expression ◽  
Expression Levels ◽  
Gingko Biloba ◽  
Mrna And Protein Expression ◽  
Cx43 Mrna ◽  
Hypoxia Reoxygenation

Gap junction communication between astrocytes plays an important role in the brain. The purpose of this study was to investigate the effects of Gingko biloba extract (GBE) on the changes of connexin 43 (Cx43) mRNA and protein expression levels of rat cortex and hippocampus induced by ischemia-reperfusion and astrocyte gap junction intercellular communication (GJIC) induced by hypoxia-reoxygenation. After 2 hours of middle cerebral artery occlusion (MCAO) followed by 24 hours of reperfusion, there was obvious neurological deficit in rats. Cx43 mRNA and protein expression levels of rat cortex and hippocampus in the ischemia hemisphere were decreased significantly. When GBE at doses of 50 and 100 mg/kg body weight was administrated by p.o. daily for 7 days, the neurological deficit was improved, and lower Cx43 mRNA and protein expression levels induced by ischemia-reperfusion were recovered to normal. The i.p. injection of nimodipine (0.7 mg/kg weight body) also showed improvement on neurological deficit and Cx43 expression levels. Astrocyte GJIC was measured by the fluorescence recovery after photobleaching (FRAP). Hypoxia-reoxygenation induced a significant decrease in GJIC. Pretreatment with GBE (100 mg/l) and nimodipine (1.6 mg/l) significantly prevented the hypoxia-reoxygenation inhibition of GJIC. These results suggest that GBE could exert its neuroprotective effects by improvement of Cx43 expression and GJIC induced by hypoxia/ischemia-reoxygenation/ reperfusion injury.

scholarly journals P6 Electroacupuncture Improved QTc Interval Prolongation by Upregulation of Connexin43 in Droperidol Treated Rats

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Feng Zhao ◽  
Suyang Cui ◽  
Libing Huang
Keyword(s):  
Protein Expression ◽  
Control Group ◽  
Qtc Interval ◽  
Interval Prolongation ◽  
Cx43 Expression ◽  
Qtc Interval Prolongation ◽  
Mrna And Protein Expression ◽  
Cx43 Mrna ◽  
And Control ◽  
Group D

Aim. This study investigated the effect of P6 EA on droperidol-induced QTc interval prolongation and Cx43 expression in ventricular muscle of rats.Methods. Twenty-four rats were randomly divided into control group (C), droperidol group (D), or EA group (E). C group rats were injected with normal saline. D group rats were injected with droperidol 0.13 mg/kg. E group rats were pretreated with EA at left P6 acupoint for 30 min and then injected with droperidol (0.13 mg/kg). QTc intervals were recorded at lead II in ECG within 120 min. Cx43 expression was measured by RT-PCR and western blotting.Result. Droperidol significantly prolonged QTc intervals compared with controls at 5 min, 10 min, 15 min, and 30 min (P<0.05). P6 EA could significantly abbreviate the prolongation of QTc interval compared with droperidol group at 5 min, 10 min, 15 min, and 30 min (P<0.05). Cx43 mRNA and proteins were significantly increased by P6 EA compared with droperidol group at 120 min (P<0.05). There were no significant differences in Cx43 mRNA and protein expression between droperidol and control group at 120 min (P>0.05).Conclusion. P6 EA could improve QTc interval prolongation induced by droperidol, which may relate to upregulation of Cx43 mRNA and protein. Antiemetic dose of droperidol had minor effects on Cx43 mRNA and protein expression at 120 min.

scholarly journals Estradiol Reduces Connexin43 Gap Junctions in the Uterus during Adenomyosis in Cows

2016 ◽  
Vol 19 (3) ◽  
pp. 609-617 ◽  
Author(s):  
A.J. Korzekwa ◽  
M. Łupicka ◽  
B.M. Socha ◽  
A.A. Szczepańska
Keyword(s):  
Protein Expression ◽  
Gap Junctions ◽  
Mrna Expression ◽  
Uterine Tissue ◽  
Cx43 Expression ◽  
Junction Protein ◽  
Uterine Adenomyosis ◽  
Mrna And Protein Expression ◽  
Gap Junction Protein ◽  
Cx43 Mrna

Abstract Adenomyosis is defined as the presence of glandular foci external to the endometrium of the uterus, either in the myometrium or/and perimetrium, depending on the progress of this dysfunction. To date, we showed that steroids secretion and prolactin expression and proliferative processes are disturbed during uterine adenomyosis in cows. During endometriosis in eutopic endometrium in women, gap junctions are down regulated. The transmembrane gap junction protein, connexin (Cx43) is necessary for endometrial morphological, biochemical and angiogenic functions. The aim of this study is recognition of adenomyosis etiology by determination of the role of Cx43 in this process. Immunolocalization and comparison of Cx43 mRNA and protein expression in healthy (N=9) and adenomyotic uterine tissue (N=9), and Cx43 mRNA expression (real time PCR) in uterine stromal – myometrium co-culture under 24-hour stimulation with 17-beta estradiol (10−7M) isolated from healthy (N=5) and adenomyotic (N=5) cows were determined. Cx43 was localized in healthy and adenomyotic uteri. mRNA and protein expression was down-regulated in uterine tissue in adenomyotic compared with healthy cows (p<0.05). Estradiol stimulated Cx43 mRNA expression in myometrial cell culture and co-culture of stromal and myometrial cells in adenomyotic compared with healthy cows (p<0.05). In summary, down-regulation of Cx43 expression in the junction zone might play an important role in pathogenesis of adenomyosis. Estradiol modulates gap junctions during adenomyosis.

BW373U86 upregulates autophagy by inhibiting the PI3K/Akt pathway and regulating the mTOR pathway to protect cardiomyocytes from hypoxia–reoxygenation injury

2020 ◽  
Vol 98 (10) ◽  
pp. 684-690
Author(s):  
Qianyi Liang ◽  
Xiaoling Huang ◽  
Chaokun Zeng ◽  
Dewei Li ◽  
Yongyong Shi ◽  
...  
Keyword(s):  
Protein Expression ◽  
Cell Viability ◽  
Ischemia Reperfusion ◽  
Underlying Mechanism ◽  
Rat Cardiomyocytes ◽  
Expression Levels ◽  
Test Kit ◽  
Reoxygenation Injury ◽  
Δ Opioid Receptor ◽  
Hypoxia Reoxygenation

The purpose of this study was to explore the protective effect of BW373U86 (a δ-opioid receptor (DOR) agonist) on ischemia–reperfusion (I/R) injury in rat cardiomyocytes and its underlying mechanism. Primary rat cardiomyocytes were cultured and pretreated with BW373U86 for intervention. The cardiomyocytes were cultured under the condition of 94% N2 and 5% CO2 for 24 h to perform hypoxia culture and conventionally cultured for 12 h to perform reoxygenation culture. The cell viability of cardiomyocytes was detected by an MTT assay (Sigma–Aldrich). The autophagy lysosome levels in cardiomyocytes were evaluated by acidic vesicular organelles with dansylcadaverine (MDC) staining (autophagy test kit, Kaiji Biology, kgatg001). The protein expression levels of LC3, p62, and factors in the PI3K/Akt/mTOR signaling pathway were detected by Western blot. Pretreatment with BW373U86 could improve the cell viability of cardiomyocytes with hypoxia–reoxygenation (H/R) injury (p < 0.05). Interestingly, after coculture of BW373U86 and PI3K inhibitor (3-methyladenine), the protein expression levels of p-Akt in cardiomyocytes were markedly increased in comparison with those in the BW373U86 group (p < 0.05). However, there were no significant differences in the protein expression levels of mTOR between the coculture group and the BW373U86 group (p > 0.05). BW373U86 upregulated autophagy to protect cardiomyocytes from H/R injury, which may be related to the PI3K/Akt/m TOR pathway.

Changes of Blood Pressure Rhythm and Clock Protein Expression Levels in Spontaneously Hypertensive Rats After Ischemia-Reperfusion

2021 ◽  
Author(s):  
Jing Jin ◽  
Yumeng Liu ◽  
Jing Huang ◽  
Dong Zhang ◽  
Jian Ge ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Protein Expression ◽  
Circadian Clock ◽  
Spontaneously Hypertensive Rats ◽  
Ischemia Reperfusion ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Expression Levels ◽  
The Relationship ◽  
Clock Protein

Abstract Objective A variety of circadian patterns of blood pressure after ischemic stroke in patients with essential hypertension appear to be a potential risk of stroke recurrence, but the mechanism is still unclear. This study intends to reveal the changes in blood pressure rhythm and circadian clock protein expression levels in spontaneously hypertensive rats (SHR) after ischemia-reperfusion, and the relationship between the two. Methods Using the SHR middle cerebral artery occlusion experimental model, the systolic blood pressure was continuously monitored for 24 hours after the operation to observe the blood pressure rhythm. The rat tail vein blood was taken every 3h, and the serum CLOCK, BMAL1, PER1 and CRY1 protein expression levels were detected by Elisa. Pearson correlation analysis counted the relationship between SHR blood pressure rhythm and circadian clock protein fluctuation after ischemia-reperfusion. Results The proportion of abnormal blood pressure patterns in the SHR + tMCAO group was significantly higher than that in the SHR group, the serum CLOCK expression was relatively constant, and the circadian rhythm of BMAL1, PER1 and CRY1 protein expression changed significantly. Pearson analysis showed that PER1 protein level was negatively correlated with dipper (r = -0.565, P = 0.002) and extreme-dipper (r = -0.531, P = 0.001) blood pressure, and was significantly positively correlated with non-dipper blood pressure (r = 0.620, P < 0.001). Conclusion The rhythm pattern of blood pressure after ischemia-reperfusion in SHR is obviously disordered, and it is closely related to the regulation of Per1 gene.

The effect of miR-6523a on growth hormone secretion in pituitary cells of Yanbian yellow cattle

2020 ◽  
Vol 100 (4) ◽  
pp. 657-664
Author(s):  
Jiuxiu Ji ◽  
Taihua Jin ◽  
Rui Zhang ◽  
Angang Lou ◽  
Yingying Chen ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Protein Expression ◽  
Luciferase Reporter ◽  
Control Group ◽  
Pituitary Cells ◽  
Expression Levels ◽  
Gh Secretion ◽  
Yellow Cattle ◽  
Mrna And Protein Expression ◽  
In Cells

Yanbian yellow cattle breeding is limited by its slow growth. We previously found that the miRNA miR-6523a is differentially expressed between Yanbian yellow cattle and Han Yan cattle, which differ in growth characteristics. In this study, we evaluated the effects of miR-6523a on growth hormone (GH) secretion in pituitary cells of Yanbian yellow cattle. Bioinformatics analyses using TargetScan and RNAhybrid, as well as dual luciferase reporter assays, showed that miR-6523a targets the 3′ untranslated region of somatostatin receptor 5 (SSTR5). We further found that the mRNA and protein expression levels of GH in pituitary cells were significantly higher in cells treated with miR-6523a mimic than in the control group (P = 0.0082 and P = 0.0069). The GH mRNA and protein expression levels were lower in cells treated with miR-6523a inhibitor than in the control group, but the difference was not significant (P = 0.064 and P = 0.089). SSTR5 mRNA and protein levels were inhibited by miR-6523a mimic compared with the control group (P = 0.0024 and P = 0.0028) and were elevated slightly by miR-6523a inhibitor (P = 0.093 and P = 0.091). These results prove that miR-6523a regulates GH secretion in pituitary cells by SSTR5. More broadly, these findings provide a basis for studies of the roles of miRNAs in animal growth and development.

scholarly journals Effects of GGT and C-S Lyase on the Generation of Endogenous Formaldehyde in Lentinula edodes at Different Growth Stages

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4203 ◽  
Author(s):  
Lei ◽  
Gao ◽  
Feng ◽  
Huang ◽  
Bian ◽  
...  
Keyword(s):  
Protein Expression ◽  
Lentinula Edodes ◽  
Growth Stages ◽  
Formaldehyde Content ◽  
Expression Levels ◽  
Mrna And Protein Expression ◽  
Relationship Of ◽  
First Time ◽  
Glutamyl Transpeptidase ◽  
Different Growth Stages

Endogenous formaldehyde is generated as a normal metabolite via bio-catalysis of γ-glutamyl transpeptidase (GGT) and L-cysteine sulfoxide lyase (C-S lyase) during the growth and development of Lentinula edodes. In this study, we investigated the mRNA and protein expression levels, the activities of GGT and C-S lyase, and the endogenous formaldehyde content in L. edodes at different growth stages. With the growth of L. edodes, a decrease was found in the mRNA and protein expression levels of GGT, while an increase was observed in the mRNA and protein expression levels of C-S lyase as well as the activities of GGT and C-S lyase. Our results revealed for the first time a positive relationship of formaldehyde content with the expression levels of Csl (encoding Lecsl) and Lecsl (C-S lyase protein of Lentinula edodes) as well as the enzyme activities of C-S lyase and GGT during the growth of L. edodes. This research provided a molecular basis for understanding and controlling the endogenous formaldehyde formation in Lentinula edodes in the process of growth.

scholarly journals MicroRNA-204-5p regulates apoptosis by targeting Bcl2 in rat ovarian granulosa cells exposed to cadmium†

2020 ◽  
Vol 103 (3) ◽  
pp. 608-619
Author(s):  
Ping Zhong ◽  
Jin Liu ◽  
Hong Li ◽  
Senbin Lin ◽  
Lingfeng Zeng ◽  
...  
Keyword(s):  
Protein Expression ◽  
Granulosa Cells ◽  
B Cell Lymphoma ◽  
Experimental Conditions ◽  
Expression Levels ◽  
Ovarian Granulosa Cells ◽  
Mrna And Protein Expression ◽  
Induced Apoptosis ◽  
Apoptosis Regulation

Abstract This study aimed to investigate whether cadmium (Cd) cytotoxicity in rat ovarian granulosa cells (OGCs) is mediated through apoptosis or autophagy and to determine the role of microRNAs (miRNAs) in Cd cytotoxicity. To test this hypothesis, rat OGCs were exposed to 0, 10, and 20 μM CdCl2 in vitro. As the Cd concentration increased, OGC apoptosis increased. In addition, Cd promoted apoptosis by decreasing the mRNA and protein expression levels of inhibition of B-cell lymphoma 2 (Bcl2). However, under our experimental conditions, no autophagic changes in rat OGCs were observed, and the mRNA and protein expression levels of the autophagic markers microtubule-associated protein 1 light chain 3 alpha (Map1lc3b) and Beclin1 (Becn1) were not changed. Microarray chip analysis, miRNA screening, and bioinformatics approaches were used to further explore the roles of apoptosis regulation-related miRNAs. In total, 19 miRNAs putatively related to Cd-induced apoptosis in rat OGCs were identified. Notably, miR-204-5p, which may target Bcl2, was identified. Then, rat OGCs were cultured in vitro and used to construct the miR-204-5p-knockdown cell line LV2-short hairpin RNA (shRNA). LV2-shRNA cells were exposed to 20 μM Cd for 12 h, and the mRNA and protein expression levels of Bcl2 were increased. Our findings suggest that Cd is cytotoxic to rat OGCs, and mitochondrial apoptosis rather than autophagy mediates Cd-induced damage to OGCs. Cd also affects apoptosis-related miRNAs, and the underlying apoptotic mechanism may involve the Bcl2 gene.

scholarly journals Uric Acid Protects against Focal Cerebral Ischemia/Reperfusion-Induced Oxidative Stress via Activating Nrf2 and Regulating Neurotrophic Factor Expression

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Bai-liu Ya ◽  
Qian Liu ◽  
Hong-fang Li ◽  
Hong-ju Cheng ◽  
Ting Yu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Uric Acid ◽  
Cerebral Ischemia ◽  
Neurological Deficit ◽  
Focal Cerebral Ischemia ◽  
Ischemia Reperfusion ◽  
Tunel Staining ◽  
Expression Levels ◽  
Cerebral Ischemia Reperfusion ◽  
Nrf2 Signaling Pathway

The aim of this study was to investigate whether uric acid (UA) might exert neuroprotection via activating the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and regulating neurotrophic factors in the cerebral cortices after transient focal cerebral ischemia/reperfusion (FCI/R) in rats. UA was intravenously injected through the tail vein (16 mg/kg) 30 min after the onset of reperfusion in rats subjected to middle cerebral artery occlusion for 2 h. Neurological deficit score was performed to analyze neurological function at 24 h after reperfusion. Terminal deoxynucleotidyl transferase-mediated dNTP nick end labeling (TUNEL) staining and hematoxylin and eosin (HE) staining were used to detect histological injury of the cerebral cortex. Malondialdehyde (MDA), the carbonyl groups, and 8-hydroxyl-2′-deoxyguanosine (8-OHdG) levels were employed to evaluate oxidative stress. Nrf2 and its downstream antioxidant protein, heme oxygenase- (HO-) 1,were detected by western blot. Nrf2 DNA-binding activity was observed using an ELISA-based measurement. Expressions of BDNF and NGF were analyzed by immunohistochemistry. Our results showed that UA treatment significantly suppressed FCI/R-induced oxidative stress, accompanied by attenuating neuronal damage, which subsequently decreased the infarct volume and neurological deficit. Further, the treatment of UA activated Nrf2 signaling pathway and upregulated BDNF and NGF expression levels. Interestingly, the aforementioned effects of UA were markedly inhibited by administration of brusatol, an inhibitor of Nrf2. Taken together, the antioxidant and neuroprotective effects afforded by UA treatment involved the modulation of Nrf2-mediated oxidative stress and regulation of BDNF and NGF expression levels. Thus, UA treatment could be of interest to prevent FCI/R injury.

scholarly journals The Effect and Mechanism of KLF7 in the TLR4/NF-κB/IL-6 Inflammatory Signal Pathway of Adipocytes

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Meixiu Zhang ◽  
Cuizhe Wang ◽  
Jinxiu Wu ◽  
Xiaodan Ha ◽  
Yuchun Deng ◽  
...  
Keyword(s):  
Protein Expression ◽  
Signaling Pathway ◽  
Transcriptional Activation ◽  
Inflammatory Cytokine ◽  
Luciferase Reporter ◽  
Signal Pathways ◽  
High Concentration ◽  
Inflammatory Signaling ◽  
Expression Levels ◽  
Mrna And Protein Expression

Objective. To investigate the role and possible molecular mechanism of Krüppel-like factor 7 (KLF7) in the TLR4/NF-κB/IL-6 inflammatory signaling pathway activated by free fatty acids (FFA). Methods. The mRNA and protein expression levels of KLF7 and the factors of TLR4/NF-κB/IL-6 inflammatory signal pathways were detected by qRT-PCR and Western blotting after cell culture with different concentrations of palmitic acid (PA). The expression of KLF7 or TLR4 in adipocytes was upregulated or downregulated; after that, the mRNA and protein expression levels of these key factors were detected. KLF7 expression was downregulated while PA stimulated adipocytes, and then the mRNA and protein expressions of KLF7/p65 and downstream inflammatory cytokine IL-6 were detected. The luciferase reporter assay was used to determine whether KLF7 had a transcriptional activation effect on IL-6. Results. (1) High concentration of PA can promote the expression of TLR4, KLF7, and IL-6 in adipocytes. (2) TLR4 positively regulates KLF7 expression in adipocytes. (3) KLF7 positively regulates IL-6 expression in adipocytes. (4) PA promotes IL-6 expression via KLF7 in adipocytes. (5) KLF7 has a transcriptional activation on IL-6. Conclusion. PA promotes the expression of the inflammatory cytokine IL-6 by activating the TLR4/KLF7/NF-κB inflammatory signaling pathway. In addition, KLF7 may directly bind to the IL-6 promoter region and thus activate IL-6.

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