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AIM: To investigate t h e impacts of theaflavins (TFs) on neuronal apoptosis and blood-brain barrier (BBB) by regulating the calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2)/5 '-adenosine monophosphate-activated protein kinase (AMPK) signaling pathway. METHODS: Ninety rats were randomly separated into sham operation group, model group, low-dose TFs group (20 mg/kg TFs), high-dose TFs group (40 mg/kg TFs), and high-dose TFs + STO-609 group (40 mg/kg TFs + 10 ΜL CaMKK2 inhibitor-STO-609), positive control group (2 mg/kg nimodipine injection), with 15 rats in each group. A rat model of intracerebral hemorrhage was induced by collagenase type VII. The behavior of rats and the water content of brain tissue were detected; the serum of rats was isolated, and the levels of inflammatory factors-vascular cell adhesion molecule-1 (VCAM-1), tumor necrosis factor-α (TNF-α), and intercellular adhesion molecule-1 (ICAM-1) were detected; brain tissue around the hematoma was collected to detect neuronal apoptosis, BBB permeability parameter-EB level, and expressions of p-CaMKK2/CaMKK2, p-AMPK/AMPK and apoptosis-related protein Bax. RESULTS: Compared with the sham operation group, the mNSS score, ICAM-1, TNF-α, VCAM-1, brain tissue water content, apoptosis rate, EB level and Bax protein expression in the model group were all increased, both pCaMKK2/CaMKK2 and p-AMPK/AMPK were decreased (P < 0.05); compared with the model group, the mNSS score, ICAM-1, TNF-α, VCAM-1, brain water content, apoptosis rate, EB level and Bax expression in the low- and high-dose TFs groups and the positive control group were all lower than those in the model group, both pCaMKK2/CaMKK2 and p-AMPK/AMPK were increased (P < 0.05); compared with the high-dose TFs group, the mNSS score, ICAM-1, TNF-α, VCAM-1, brain tissue water content, apoptosis rate, EB level and Bax expression were all increased in the high dose TFs + STO-609 group, both p-CaMKK2/CaMKK2 and p-AMPK/AMPK were decreased (P < 0.05). CONCLUSION: TFs can reduce neuronal apoptosis, inflammatory response, BBB permeability, and play a protective role in rats with cerebral hemorrhage injury. Its mechanism is related to the activation of CaMKK2/AMPK signaling pathway.
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Z-VAD-FMK was combined with hypoxia-reoxygenation (H/R) injury to establish a necroptosis model of H9c2 cells to mimic the pathological changes of myocardial ischemia reperfusion injury (MIRI) in vitro and to study the effect and mechanism of tilianin against myocardial ischemia-reperfusion injury. A cell counting kit-8 (CCK-8) was used to detect cell viability, and commercial kits were used to detect lactate dehydrogenase (LDH) and superoxide dismutase (SOD) in the cell culture supernatant. Hoechst 33342/PI immunofluorescence staining was used to detect cell death. DCFH-DA, BBcellProbeTMM61, and JC-1 probes were used to detect reactive oxygen species (ROS), mitochondrial permeability transition pore (mPTP), and mitochondrial membrane potential (MMP), respectively. An enzyme-linked immunosorbent assay (ELISA) method was used to detect the release of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6). The results show that the cell viability, SOD activity, and MMP of the model group induced by H/R injury decreased, as compared with control group, but the necroptosis rate, LDH level, and ROS release increased significantly. Furthermore, mPTP of the model group cells opened, and TNF-α, IL-1β, and IL-6 levels were significantly higher. Molecular docking modeling showed that tilianin can bind to calmodulin-dependent protein kinase II (CaMKII), and Western blot results showed that compared with control group, the expression levels of p-CaMKII and phospho-mixed lineage kinase domain-like protein increased in the model group, and tilianin could decrease the expression level of these proteins. The above results indicate that tilianin can protect H9c2 cells by inhibiting the phosphorylation of CaMKⅡ at threonine 287, protecting mitochondrial function, and inhibiting the opening of mPTP to prevent necroptosis. This study has value for research on new methods to treat H/R injury.
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Objective::To study the effect of Hei Xiaoyaosan on the expression of calcium calmodulin-dependent protein kinase Ⅱ alpha(CaMKⅡα) and its phosphorylation in hippocampus and cortex of mice with Alzheimer's disease. Method::After weighing, 30 APP/PSI transgenic male mice were divided into model group, donepezil hydrochloride group and Hei Xiaoyaosan group according to random principle and 10 in each group.At the same age, wild-type C57BL/6 10 mice of the same species were treated as blank group. Donepezil hydrochloride group (6 g·kg-1) and Hei Xiaoyaosan group (3.25 mg·kg-1) were administered for 90 days, then the behavior of all the mice were detected by Morris water maze, the expression of CaMKⅡα, p-CaMKⅡα proteins in hippocampus and cortex by immunohistochemical technique and Western blot. Result::After intervention 3 months, compared with blank group, the average escaping latency periods prolonged significantly and the number of cross-platform and effective areas were decreased distinctly in model group mice(P<0.01), CaMKⅡα protein relative expression decreased significantly(P<0.01), p-CaMKⅡα protein relative expression increased significantly(P<0.01). Compared with the model group, the escape latency of donepezil hydrochloride and Hei Xiaoyaosan group were significantly shortened, and the number of crossing platforms and effective areas was significantly increased (P<0.05, P<0.01), the expression of CaMKⅡα protein in the hippocampus and cortex of drug groups was significantly increased (P<0.01), p-CaMKⅡα protein in the hippocampus and cortex of drug groups was significantly decreased (P<0.05, P<0.01). Conclusion::Hei Xiaoyaosan can improve the learning and memory ability of AD mice by regulating the expression of CaMKⅡα and its phosphorylation, which are key proteins involved in the mechanism of cell memory formation in different brain regions of AD mice.
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Alzheimer's disease（AD） is an incipient aging neurodegenerative disease， which increases rapidly along with the development trend of social aging and seriously threatens the health of the people. In the absence of effective preventive measures， it will have an enormous impact on the socio-economic and healthcare system. The study found that abnormal cell signal transduction is a key link in many diseases. Cell signal transduction theory has been widely used to clarify the essence of traditional Chinese medicine visceral image and the mechanism of traditional Chinese medicine. 'Correlation of Liver and Kidney' is one of the core plates of the theory of 'Correlation of Five Organs'， which is suitable for explaining the pathogenesis of complex diseases and the correlation of multiple syndromes， and guiding the prescription of clinical syndrome. Hei Xiaoyaosan， as the first choice compound for the prevention and treatment of AD based on the theory of "Correlation of Liver and Kidney' in our team， can play the effects of prevention and treatment by soothing liver and nourishing blood， strengthening spleen and tonifying kidney， and promoting brain collaterals and dredging viscerab spirit. Based on the theory of 'Correlation of Liver and Kidney'， this paper expounds the pathogenesis of AD from the perspective of traditional Chinese medicine， and puts forward the methods and ideas of the preventing and treating of AD from Ca2+-calcium/calmodulin dependent protein （CaM）/calcium/calmodulin dependent protein kinaseⅡ（CaMKⅡ）-cyclic adenosine phosphate reactive element binding protein （CREB） cell signal transduction pathway by consulting literatures and previous studies.
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Objective To explore the protective effect and mechanism of swimming rehabilitation training on learning and memory impairment of cerebral ischemia reperfusion gerbil. Methods Forty adult healthy male gerbils were randomly divided into sham group,sham+swimming group (Sham+S group),cere-bral ischemia / reperfusion group ( I/R group), cerebral ischemia/reperfusion+swimming group ( I/R+S group),with 10 rats in each group. The gerbil models of cerebral ischemia/reperfusion in I/R group and I/R+S group were established by blocking bilateral common carotid artery,while for gerbils in Sham group and Sham+S group, only bilateral common carotid arteries of gerbils were exposed, but no arteries were clamped. Morris water maze was used to detect the changes of learning and memory function in rats. Oxida- tive stress injury in hippocampal neurons was detected by detection kit analysis. And the expression of Bax, Bcl-2 and CaMK Ⅱ protein in hippocampal tissue was detected by Western blot. Results Compared with Sham group,the gerbils in I/R group had longer positioning cruise time and less shuttle times ( both P<0. 01). Compared with I/R group,the positioning cruise time and shuttle times in I/R+S group were signifi-cantly shortened and increased respectively (both P<0. 01). Compared with sham group( SOD:(123. 13± 7. 50)U/mg,GSH:(42. 10±2. 17) μg/g,GSH-Px:(61. 37±2. 51) μg/g,MDA:( 2. 91± 0. 23) nmol/mg), the activities of SOD,GSH,GSH-Px in I/R group decreased significantly,while the content of MDA increased significantly(SOD:(75. 50±6. 96)U/mg,GSH:(22. 50±1. 64) μg/g,GSH-Px:(33. 15±2. 04)μg/g,MDA:(5. 96±0. 32)nmol/mg;all P<0. 01). Furthermore,compared with I/R group,the above indexes in I/R+S group were significantly reversed(SOD:(110. 30±5. 90)U/mg,GSH:(34. 31±1. 73)μg/g,GSH-Px:(50. 13 ±2. 31)μg/g,MDA:(3. 57±0. 29) nmol/mg;all P<0. 01). Compared with Sham group,the expression of Bax protein in hippocampus of gerbils in I/R group was increased,while the expression of Bcl-2 protein and p-CaMK Ⅱ protein was decreased (all P<0. 05). Compared with I/R group,the expression of Bax protein in hippocampus of gerbils in I/R+S group was decreased,while the expression of Bcl-2 protein and p-CaMK Ⅱprotein was increased (all P<0. 05). Conclusion Swimming rehabilitation training can improve learning and memory impairment of gerbils after ischemia-reperfusion through anti-oxidative stress and anti-apoptosis, which may be related to CaMK Ⅱ signaling system.
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Calcium (Ca2+) has long been recognized as a crucial intracellular messenger attaining stimuli specific cellular outcomes via localized signaling. Ca2; binding proteins, such as calmodulin (Ca.M) and its target proteins are key to Ca2;-dependent signaling events. Calcium/calmodulin-dependent protein kinase type II (CaMK II) is a highly abundant polymer enzyme comprising a significant fraction of total protein in mammalian forebrain and forming a major component of the postsynaptic density. In recent years, studies have shown that CaMK D contains four subtypes of a, (3, y and 8, in which CaMK II a and p are mainly expressed in nerve tissues and 7 and 6 are expressed in the whole body. They are essential for certain synaptic plasticity and memory consolidation processes, both in the central nervous system and in the excitability of the nervous system and in some neurological diseases. CaMK II may play an important role in the pathogenesis of some nervous system diseases. Previous studies have also shown that CaMK II 8 plays an important role in promoting neuronal survival. The structure of CaMK H and its role in nervous system and its relationship with related nervous system diseases will be reviewed.
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Objective To evaluate the relationship between NR2B subunit-containing N-methyl-D-aspartate (NMDA) receptors (NR2B receptors) and Ca2+/calmodulin-dependent protein kinase Ⅱ α (CaMK Ⅱ α) in the spinal cord during remifentanil-induced hyperalgesia in a rat model of incisional pain (IP).Methods Forty male Sprague-Dawley rats in which intrathecal and caudal catheters were successfully placed,weighing 260-280 g,aged 2-3 months,were divided into 4 groups (n=10 each) using a random number table method:control group (group C),remifentanil plus IP group (group RI),NR2B antagonist Ro 25-6981 group (group Ro) and remifentanil plus IP plus Ro 25-6981 group (group RI+Ro).In group C,normal saline 0.1 ml was intrathecally injected,and 10 min later normal saline was infused for 60 min via the tail vein at a rate of0.1 ml · kg-1 · min-1.In group RI,normal saline 0.1 ml was intrathecally injected,and 10 min later remifentanil was infused for 60 min via the tail vein at a rate of 1.0 μg · kg-1 · min-1,and IP was established immediately after onset of remifentanil infusion.In group Ro,Ro 25-6981 (0.1 ml) 10 μg was intrathecally injected,and 10 min later normal saline was infused for 60 min via the tail vein at a rate of 0.1 ml · kg-1 · min-1.In group RI+Ro,Ro 25-6981 (0.1 ml) 10 μg was intrathecally injected,and 10 min later remifentanil was infused for 60 min via the tail vein at a rate of 1.0 μg · kg-1 · min-1,and IP was established immediately after onset of remifentanil infusion.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 24 h before intravenously infusing normal saline or remifentanil and at 2,6,24 and 48 h after the end of infusion (T0-4).The rats were sacrificed after the last behavioral test,and the L4-6 segment of the spinal cord was removed for determination of the expression of NR2B in total and membrane protein (tNR2B and mNR2B) and expression of CaMK Ⅱ α in total protein (tCaMK Ⅱ α) and phosphorylated CaMK Ⅱ α (pCaMKⅡα).The ratios of mNR2B/tNR2B and pCaMKⅡα/tCaMK Ⅱα were calculated.Results Compared with group C,the MWT was significantly decreased,TWL was shortened,the expression of tNR2B,mNR2B,tCaMKⅡα and pCaMKⅡα was up-regulated,and the ratios of mNR2B/tNR2B and pCaMK Ⅱ α/tCaMK Ⅱ α were increased in group RI (P＜0.05 or 0.01).Compared with group RI,the MWT was significantly increased,TWL was prolonged,the expression of tNR2B,mNR2B,tCaMKⅡα and pCaMKⅡα was down-regulated,and the ratios of mNR2B/tNR2B and pCaMK Ⅱ α/tCaMK Ⅱ α were decreased in group RI+ Ro (P＜0.05 or 0.01).Conclusion Enhanced function of NR2B can activate CaMKⅡα during remifentanil-induced hyperalgesia,which may be involved in the mechanism of remifentanil-induced hyperalgesia in a rat model of IP.
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Objective To evaluate the effect of propofol on subunit 2B-containing N-methyl-D-aspartate receptor (NR2B)/calcium/calmodulin-dependent protein kinase Ⅱ alpha (CaMKⅡα) signaling pathway in brain injury induced by hepatic ischemia-reperfusion (I/R) in preadolescent mice.Methods Sixty-four healthy clean-grade C57BL/6 mice,aged 2 weeks,weighing 4-6 g,were randomized into 4 groups (n=16 each) using a random number table method:sham operation group (S group),hepatic I/R group (HI/R group),propofol control group (P group),and propofol plus hepatic I/R group (P+ HI/R group).The model of 70％ liver I/R injury was established by clamping the left and middle lobe vascular trunk in anesthetized mice.Propofol 20 mg/kg was intraperitoneally injected before operation at 30 min before establishing the model in P and P+HI/R groups.The equal volume of normal saline was given instead in P and P + HI/R groups.Eight mice of each group were sacrificed at 6h of reperfusion,hippocampal tissues were obtained for examination of pathological changes of hippocampal tissues and for determination of neuronal apoptosis (by TUNEL) and expression of NR2B,phosphorylated NR2B (p-NR2B),CaMKⅡα and phosphorylated CaMKⅡα (p-CaMKⅡα) (by Western blot).The remaining 8 mice in each group were used for Morris water maze test at 1 month after establishing the model.Apoptosis index was calculated.Results Compared with group S,the escape latency was significantly prolonged,the percentage of the time of staying at the original platform quadrant was decreased,the expression of p-NR2B and p-CaMKⅡα was up-regulated,and apoptosis index was increased in HI/R and P+HI/R groups (P＜0.05),and no significant change was found in the parameters mentioned above in group P (P＞0.05).Compared with group HI/R,the escape latency was significantly shortened,the percentage of the time of staying at the original platform quadrant was increased,the expression of p-NR2B and p-CaMKⅡα was down-regulated,and apoptosis index was decreased (P＜0.05),and the pathological changes of hippocampal tissues were significantly attenuated in group P+HI/R.Conclusion The mechanism by which propofol reduces brain injury induced by hepatic I/R may be related to inhibiting NR2B/CaMKⅡα signaling pathway in preadolescent mice.
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Objective To investigate the changes in the expression of Ca2+/calmodulin-dependent protein kinase Ⅱ α (CaMK Ⅱ α) in the spinal cord and dorsal root ganglia (DRG) during remifentanil-induced hyperalgesia in a rat model of incisional pain (IP).Methods Thirty-two male Sprague-Dawley rats in which caudal vein catheter was successfully placed,aged 260-280 g,were divided into 4 groups (n=8 each) using a random number table method:control group (group C),IP group,remifentanil group (group R) and remifentanil plus IP group (group RIP).Normal saline was infused via the caudal vein for 60 min at a rate of 0.1 ml · kg-1 · min-1 in group C.Normal saline was infused via the caudal vein for 60 min at a rate of 0.1 ml · kg-1 · min-1,and the model of IP was simultaneously established in group IP.Remifentanil was infused via the caudal vein for 60 min at a rate of 1.0 μg · kg-1 · min-1 in group R.Remifentanil was infused via the caudal vein for 60 min at a rate of 1.0 μg · kg-1 · min-1,and the model of IP was simultaneously established in group RIP.Mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 24 h before infusion and 2,6,24 and 48 h after infusion (T0-4).The rats were sacrificed after the last behavioral test,and L4-6 segment of the spinal cord and DRGs were removed for determination of the expression of total and phosphorylated CaMK Ⅱ α (tCaMK Ⅱ α,pCaMK Ⅱ α) by Western blot.The ratio of pCaMK Ⅱ /tCaMK Ⅱ α was calculated.Results Compared with group C,MWT was significantly decreased,TWL was shortened,the expression of tCaMK Ⅱ α and pCaMK Ⅱ α in the spinal cord and DRGs was up-regulated,and the ratio of pCaMK Ⅱ α/tCaMK Ⅱ α was increased in I,R and RIP groups (P＜0.05 or 0.01).Compared with group IP and group R,MWT was significantly decreased,TWL was shortened,the expression of tCaMK Ⅱ α and pCaMK Ⅱ α in the spinal cord and DRGs was up-regulated,and the ratio of pCaMK Ⅱ α/tCaMK Ⅱ α was increased in group RIP (P＜0.05 or 0.01).Conclusion The mechanism by which remifentanil induces hyperalgesia may be related to upregulated expression of CaMK Ⅱ α in the spinal cord and DRGs in a rat model of IP.
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Objective To evaluate the effect of propofol on the expression of programmed death-ligand-1 (PD-L1) in pancreatic cancer cells and the relationship with NMDA/Ca2+/calmodulin-dependent protein kinase Ⅱ (CaMK Ⅱ)/hypoxia-inducible factor-1α (HIF-1α) pathway.Methods Human pancreatic cancer cells were divided into 5 groups (n=16 each) by a simple random sampling method:control group (group C),propofol group (group P),KN93 (CaMK Ⅱ inhibitor) group,MK801 (NMDA receptor antagonist) group and propofol plus rapastinel (NMDA receptor agonist) group (group PR).Cells were cultured in DMEM supplemented with 10％ fetal bovine serum in group C.Cells were incubated for 8 h with 50 μmol/L propofol in group P.Cells were incubated for 8 h with 10 μmol/L KN93 in group KN93.Cells were incubated for 8 h with 500 μmol/L MK801 in group MK801.Cells were incubated for 8 h with 50 μmol/L propofol and 20 μmol/L rapastinel in group PR.After the end of treatment in each group,the cell viability was measured using CCK8 assay,the expression of PD-L1,HIF-1α,CaMK Ⅱ and phosphorylated CaMK Ⅱ (p-CaMK Ⅱ) was detected by Western blot,and intracellular calcium concentrations were determined by Fluo3/AM probe.Results Compared with group C,the cell viability was significantly decreased,the expression of PD-L1,HIF-1α and p-CaMK Ⅱ was down-regulated,and intracellular calcium concentrations were decreased in P,KN93 and MK801 groups (P＜0.05),and no significant change was found in group PR (P＞0.05).Compared with group P,the cell viability was significantly enhanced,the expression of PD-L1,HIF-1α and p-CaMK Ⅱ was up-regulated,and intracellular calcium concentrations were increased in group PR (P＜0.05).Conclusion The mechanism by which propofol inhibits the malignant potential of pancreatic cancer cells may be related to inhibiting NMDA/CaMK Ⅱ/HIF-1α pathway and down-regulating PD-L1 expression.
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Objective To evaluate the role of spinal CX3C chemokine receptor 1 (CX3CR1) in inflammatory pain and the relationship with calmodulin (CaM)-calmodulin-dependent protein kinaseⅡ(CaMKⅡ) signaling pathways in mice.Methods Ninety-six pathogen-free healthy male C57BL6 mice,weighing 25-27 g,were divided into 3 groups using a random number table:control group (group C,n=30),inflammatory pain group (group IP,n=36) and CX3CR1 antagonist group (group CA,n=30).Inflammatory pain was induced by injecting complete Freund′s adjuvant (CFA) 50 μl into the plantar surface of right hind paws in IP and CA groups,while the equal volume of normal saline was given instead in group C.In group CA,CX3CR1 antagonist (diluted to 1 μg/5 μl in phosphate buffer solution) was intrathecally injected at 1 h before CFA injection.The thermal paw withdrawal latency (TWL) was measured at 30 min before CFA injection (T0) and 30 min,1 h,2 h and 4 h after CFA injection (T2-4).The animals were then sacrificed,and the spinal cord was removed for determination of the expression of phosphorylated CaMKⅡ (p-CaMKⅡ),phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB) and c-fos (by Western blot) and expression of CaMKⅡ,CREB and c-fos mRNA (using real-time polymerase chain reaction).Immunofluorescence was used to determine that p-CAMKⅡ was expressed in microglia.Results Compared with group C,the TWL was significantly shortened at T2-4,and the expression of p-CaMKⅡ,p-CREB and c-fos protein and mRNA was up-regulated at T1-4 in IP and CA groups (P<0.05).Compared with group IP,the TWL was significantly prolonged at T2-4,and the expression of p-CaMKⅡ,p-CREB and c-fos protein and mRNA was down-regulated at T1-4 in group CA (P<0.05).p-CaMKⅡ was co-expressed with the microglial specific biomarker.Conclusion CX3CR1 is involved in the development and maintenance of inflammatory pain through activating CaM-CaMKⅡsignaling pathways in mice.
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Objective To evaluate the effect of sevoflurane on hippocampal calcium/calmodulindependent protein kinase Ⅱ (CaMK Ⅱ)/cyclic adenosine monophosphate response element-binding protein (CREB) signaling pathway in aged rats.Methods Sixty pathogen-free healthy male Sprague-Dawley rats,aged 18 months,weighing 600-750 g,were divided into 2 groups (n=30 each) using a random number table:control group (group C) and sevoflurane group (group Sev).Group Sev inhaled 2％ sevoflurane in the mixture of 50％ air and oxygen (2 L/min) for 4 h.Group C inhaled the mixture of 50％ air and oxygen (2 L/min) for 4 h.Morris water maze test was performed on 6 days before anesthesia and 1 day after anesthesia.The escape latency,swimming distance,frequency of crossing the original platform and time of staying at the platform quadrant Ⅱ were recorded.On 1,3 and 7 days after anesthesia,the rats were sacrificed,and the hippocampus was obtained for determination of the expression of CaMK Ⅱ,phosphorylated CaMK Ⅱ,CREB and phosphorylated CREB by Western blot.Results Compared with group C,the escape latency and swimming distance were significantly prolonged,the frequency of crossing the original platform was decreased,and the time of staying at the platform quadrant Ⅱ was reduced on 5th day of training and 1 day after anesthesia,and the expression of CaMK Ⅱ,phosphorylated CaMK Ⅱ,CREB and phosphorylated CREB was down-regulated after anesthesia in group Sev (P＜ 0.05).Conclusion Sevoflurane leads to cognitive decline through inhibiting hippocampal CaMK Ⅱ/CREB signaling pathway in aged rats.
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Calcium/cahnodulin-dependent protein kinase Ⅱ (CaMK Ⅱ) is a multifunctional serine/threonine protein kinase.It plays a vital role in the regulation of neurotransmitters,cell metabolism,and synaptic plasticity,as well as in many diseases of the nervous system.As CaMK Ⅱ alpha is specifically located at excitatory neurons,it has long been regarded as crucial for the treatment of epilepsy.CaMK Ⅱ shows decreased activity after seizures in different in vivo and in vitro models of epilepsy.This article provides a new theoretical basis for further research on the pathological process of epilepsy and its treatment,by exploring several recent experimental studies on CaMK Ⅱ and epilepsy.
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Objective@#To investigate the effect of zoledronate on protein interaction between Ca2+/calmodulin-dependent protein kinaseⅡ(CaMKⅡ) and calmodulin and protein expression of nuclear factor of activation of T cells-1 (NFATc1) and tartrate resistant acid phosphatase (TRAP) during osteoclast differentiation. @*Methods@#Mouse RAW264.7 cells were divided into group A and B and were cultured. Group A was induced with 50 mg/L receptor activator of NF-κB ligand (RANKL) for osteoclastogenesis, and group B was treated with 1×10-6 zoledronate for two days from day 2. Co-immunoprcipitation (Co-IP) and reverse Co-IP were used to detect the protein-binding between CaMKⅡ and calmodulin. Western-blotting and immunofluorescent cytochemistry were also used to detect the protein level of NFATc1 and TRAP in both groups. Osteoclast formation was also analyzed. @*Results@#In group B, the number of osteoclasts, number and size of dentin resorption lacunaes were 11.3±1.5, 8.7±2.1 and (5 034.4±775.4) μm2 respevtively, which were significantly lower than those (37.7±5.7, 23.0±4.0 and [15 042.7±1 906.0] μm2) in group A (P<0.01). Co-IP and reverse Co-IP examination indicated that protein-binding between CaMKⅡ and calmodulin significantly decreased by 59.8% and 50.9% in group B compared with group A (P<0.01). The protein level of calmodulin and CaMKⅡ in total cellular proteins also significantly decreased by 52.1% and 51.5% in group B compared with group A (P<0.01). NFATc1 and TRAP protein decreased by 52.4% and 38.9% in group B than in group A (P<0.01), respectively. @*Conclusions@#Zoledronate could significantly inhibit protein-binding between CaMKⅡ and calmodulin and down-regulate protein level of NFATc1 and TRAP.
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Atrial structural remodeling and electrical remodeling are the core of atrial fibrillation.Oxidative stress directly activates calcium/calmodulin-dependent protein kinase Ⅱ (CaMKⅡ), and induces electrical remodeling and atrial structural remodeling characterized by reduced atrial effective refractory period, which becomes the pathological basis of atrial fibrillation.Therefore, the study of the relationship between the oxidative CaMKⅡ and atrial remodeling will help to elucidate the pathogenesis of atrial fibrillation and to prevent or reverse atrial remodeling by lowering CaMKⅡ phosphorylation to reduce the incidence of atrial fibrillation.
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Heart failure is mainly characterized by myocardial systolic dysfunction,which is based on excitement-contraction coupling on the cellular level,and calcium (Ca2+) signaling plays a very important role in this process.The ryanodine receptor (RyR)/calcium release channel on the sarcoplasmic reticulum (SR) is the major Ca2+ source of required for cardiac muscle excitation contraction coupling.RyR2 phosphorylation is the basis of SR calcium release,and RyR2 phosphorylation is mainly controled by protein kinase A (PKA) and calcium/calmodulin dependent protein kinase Ⅱ (CaMK Ⅱ).Although widely research in this area,excessive activation of RyR2 phosphorylation involved in the pathogenesis of heart failure are still controversial,which is discussed in this review.
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OBJECTIVE: To observe the changes of intracellular calcium ([Ca2＋]i) concentration and expression of calcium/calmodulin dependent protein kinaseⅡ (CaMKⅡ) in spinal dorsal horn neurons of spared nerve injury (SNI) rats, so as to explore its mechanisms underlying improvement of neuropathic pain. METHODS: One hundred and ten SD rats were randomly divided into 5 groups: sham control, model, EA, AP-5 and L-NAME groups. The sham group underwent only a simple separation of the sciatic nerve but without ligation and abscission. The neuropathic pain model was established by abscission of the right tibial and common peroneal nerve. EA (2 Hz, 1－3 mA) was applied to right "Weizhong" (BL 40) and "Huantiao" (GB 30) for 30 min, once a day for 7 days, starting from day 11 after surgery. For rats of the AP-5 and L-NAME groups, AP-5 (a competitive antagonist for NMDA receptor, 0.7 mg·kg－1·d－1) and L-NAME (a non-selective antagonist for nitric oxide synthase [NOS], 60 mg·kg－1·d－1) were respectively administrated by intraperitoneal injection, once daily for 7 days. The mechanical pain threshold was measured, and the calcium fluorescence intensity (shown by Fluo-3/AM calcium fluorescence indicator) of the superficial layer of the lumbar spinal cord (L 4－L 6) was measured by immunohistochemical staining and the expression of spinal cord (L 4－L 6) CaMK Ⅱ protein was detected by Western blot (WB). RESULTS: After modeling, the mechanical pain threshold was significantly decreased on day 10 and 16 after operation in comparison with the sham operation group and baseline data of pre-operation in each group (P<0.01), and remarkably increased in the EA, AP-5 and L-NAME groups relevant to the model group on day 16 (P<0.01, P<0.05), while the effect of EA was significantly superior to that of AP-5 and L-NAME groups (P<0.05), suggesting a reduction of EA analgesia after administration of AP-5 and L-NAME. The concentration of intracellular [Ca2＋]i was significantly higher in the model group than in the sham group, and considerably lower in the EA, AP-5 and L-NAME groups than in the model group (P<0.01, P<0.05). Moreover, the expression level of CaMKⅡ shown by WB and immunohistochemical staining was significantly higher in the model group than in the sham group (P<0.05) and obviously lower in the EA group (not the AP-5 and L-NAME groups) than in the model group on day 16 after the intervention (P<0.05). It suggests an involvement of glutamate NMDA receptor and NMDAR-NOS/NO signaling in the analgesic effect and CaMKⅡ expression down-regulation of EA. CONCLUSIONS: EA can ease pain in rats with neuropathic pain, which is closely related to its effect in reducing the calcium concentration and the expression of CaMKⅡ in the lumbar spinal cord, possibly mediated by glutamate NMDA receptor and NMDAR-NOS/NO signaling.
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Objective To explore the effects of luteolin on cognition function in pentylenetetrazol (PTZ)-induced epileptic rats and related mechanism.Methods Fifty male SD rats were randomly divided into a normal control group(n=8), a model group(n=12), and groups of 25, 50 mg/kg luteolin(both ofn=11), as well as 100 mg/kg luteolin group(n=8). Those rats were given different doses of luteolin (25, 50 and 100 mg/kg, daily, intragastric administration) for 36 consecutive days. Similarly, rats of the normal control group and the model group were given 0.5% sodium carboxymethyl cellulose suspension liquid via intragastric administration. Thirty minutes later, a model of epilepsy was induced using PTZ (40 mg/kg, daily) via intraperitoneal injection except the control group. Learning and memory of rats were evaluated by Morris water maze and novel objective recognition trials(including escape latency and recognition index). The levels of CaM and CaMPK were determined by ELISA methods, and expression of Ras proteins in the hippocampus were detected by Western Blot.Results Compared with the model group, luteolin treatment groups significantly shorten the escape latency(28.51 ± 3.84 s, 19.77 ± 5.41 s, 14.86 ± 2.76 svs. 37.08 ± 5.18 s) in the Morris water maze, and increased recognition index(18.77% ± 2.02%, 25.06% ± 4.32%, 31.92% ± 2.65%vs. 13.87% ± 2.14%) in the novel objection trial(P<0.05 orP<0.01). Meanwhile, CaM(140.33 ± 13.52 ng/L, 124.26 ± 9.97 ng/L, 113.52 ± 11.57 ng/Lvs. 158.36 ± 10.68 ng/L) and CaMPK(8.25 ± 1.37 ng/ml, 7.69 ± 0.84 ng/ml, 6.74 ± 0.93 ng/mlvs. 9.87 ± 1.02 ng/ml) were significantly decreased(P<0.05 orP<0.01). What’s more, the expression of Ras proteins(0.99 ± 0.08, 0.76 ± 0.07, 0.52 ± 0.07vs. 1.58 ± 0.12) was obviously decreased compared with the model group(P<0.05 orP<0.01).Conclusion Luteolin could effectively improve the cognition dysfunction of epileptic rats, and the mechanism might be relevant to regulate the CaM-CaMPK signaling pathway via down-regulation of CaM, CaMPK, as well as Ras protein.
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Objective To evaluate the role of calcium/calmodulin-dependent kinase Ⅱ alpha (CaMK Ⅱα) in the central nucleus of the amygdale (CeA) in fentanyl-induced hyperalgesia in rats and the relationship with miniature excitatory postsynaptic currents (mEPSCs).Methods Thirty-two male Sprague-Dawley rats,weighing 50-80 g,in which the CeA was successfully cannulated,were randomly divided into 4 groups (n=8 each) using a random number table:control 1 group (group C1),fentanylinduced hyperalgesia 1 group (group FIH1),KN92 group,and KN93 group.Normal saline was injected subcutaneously,and dimethyl sulfoxide (DMSO) was given into the amygdale in group C1.In group FIH1,fentanyl was injected subcutaneously (60 μg/kg per time,4 times in total,15-min interval,cumulative dose of 240 μg/kg) to establish the model of hyperalgesia.In KN92 and KN93 groups,KN92 and KN93 10 nmol were given into the CeA after establishing the model.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal threshold (TWT) were measured at 6 and 7 h after fentanyl or normal saline injection.Another 12 Sprague-Dawley rats were selected and randomly divided into either control 2 group (group C2) or fentanyl-induced hyperalgesia 2 group (group FIH2) using a random number table with 6 rats in each group.The brains were removed and sliced 12 h later,and the frequency and amplitude of mEPSCs were recorded.KN93 10 nmol was then added to the artificial cerebral spinal fluid,and the frequency and amplitude of mEPSCs were recorded by whole cell patch-clamp technique.Results Compared with group C 1,the MWT and TWT were significantly decreased at 6 h after fentanyl or normal saline injection in FIH1,KN92 and KN93 groups,and at 7 h after fentanyl or normal saline injection in FIH and KN92 groups (P＜0.05).Compared with group FIH1,the MWT and TWT were significantly increased at 7 h after fentanyl or normal saline injection in group KN93 (P＜0.05),and no significant change was found in group KN92 (P＞0.05).Compared with group C2,the frequency and amplitude of mEPSCs were significantly increased before administration of KN93 (P ＜ 0.05),and no significant change was found in the frequency and amplitude of mEPSCs after administration of KN93 in group FIH2 (P＞0.05).Compared with the value before KN93 administration,no significant change was found in the frequency and amplitude of mEPSCs after administration of KN93 in group C2 (P＞0.05),and the frequency and amplitude of mEPSCs were significantly decreased after administration of KN93 in group FIH2 (P＜ 0.05).Conclusion Activation of CaMK Ⅱ α in the CeA enhances synaptic excitation in neurons,which is involved in fentanyl-induced hyperalgesia in rats.
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Objective To investigate the influence of dexmedetomidine on expressions of protein kinase c (PKC)γ, cal?cium/calmodulin-dependent protein kinase (CaMK)Ⅱαand pCaMKⅡαin spinal cord in rats with incisional pain (IP) and remifentanil-induced hyperalgesia. Methods Forty male Sprague-Dawley rats, aged 2-3 months, weighing 240-260 g, were randomly divided into 5 groups (n=8 each):blank control group (group C), remifentanil+incisional pain group (group R+I), dexmedetomidine + remifentanil + incisional pain group (group D+R+I), dexmedetomidine + remifentanil + incisional pain+phorbol myristate acetate+DMSO group (group D+R+I+P+DMSO) and dexmedetomidine+remifentanil+incisional pain+DMSO group (group D+R+I+DMSO). The incisional pain rat model was established by a plantar incision in left hind paw. Remifentanil was infused at a rate of 1.2μg·kg-1·min-1 for 90 min via the caudal vein. Dexmedetomidine was adminis?tered subcutaneously at a dose of 50μg/kg at 30 min before plantar incision. Phorbol myristate acetate and DMSO were intra?thecally injected at a dose of 10 μL. Paw withdrawal latency (PWL) to thermal stimulation and paw withdrawal threshold (PWT) to von Frey hair stimulation were measured 24 h before remifentanil infusion (T0) and at 2, 6, 24 and 48 h (T1-4) after intraveonus remifentanil injection. The rats were sacrificed after the last behavioral test and the L 4-6 segment of spinal cord was removed to determine the expressions of PKCγ, CaMKⅡαand pCaMKⅡαin spinal cord by Western blot analysis. Re? sults Compared with group C, the value of PWL was significantly shortened and PWT was significantly decreased except T0, and the expressions of PKCγ, CaMKⅡαand pCaMKⅡαwere up-regulated in other groups. Compared with group R+I, the value of PWL was significantly prolonged and PWT was significantly increased, the expressions of PKCγ, CaMKⅡαand pCaMKⅡαwere down-regulated in group D+R+I and group D+R+I+DMSO. Compared with group D+R+I, the value of PWL was significantly shortened and PWT was significantly decreased, the expressions of PKCγ, CaMKⅡαand pCaMKⅡαwere up-regulated in group D+R+I+P+DMSO. Compared with group D+R+I+P+DMSO, the value of PWL was significantly prolonged and PWT was significantly increased, the expressions of PKCγ, CaMKⅡαand pCaMKⅡαwere down-regulated in group D+R+I+DMSO. Conclusion Dexmedetomidine can reduce the expressions of PKCγ, CaMKⅡαand pCaMKⅡαin spinal cord in rats with IP and hyperalgesia induced by remifentanil.