Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 661
Filtrer
1.
Article de Chinois | WPRIM | ID: wpr-1039123

RÉSUMÉ

Polycystin-2 (also known as PC2, TRPP2, PKD2) is a major contributor to the underlying etiology of autosomal dominant polycystic kidney disease (ADPKD), which is the most prevalent monogenic kidney disease in the world. As a transient receptor potential (TRP) channel protein, PC2 exhibits cation-permeable, Ca2+-dependent channel properties, and plays a crucial role in maintaining normal Ca2+ signaling in systemic physiology, particularly in ADPKD chronic kidney disease. Structurally, PC2 protein consists of six transmembrane structural domains (S1-S6), a polycystin-specific “tetragonal opening for polycystins” (TOP) domain located between the S1 and S2 transmembrane structures, and cytoplasmic N- and C-termini. Although the cytoplasmic N-terminus and C-terminus of PC2 may not be significant in the gating of PC2 channels, there is still much protein structural information that needs to be thoroughly investigated, including the regulation of channel function and the assembly of homotetrameric ion channels. This is further supported by the presence of human disease-associated mutation sites on the PC2 structure. Moreover, PC2 synthesized in the endoplasmic reticulum is enriched in specific subcellular localization via membrane transport and can assemble itself into homotetrameric ion channels, as well as form heterotrimeric receptor-ion channel complexes with other proteins. These complexes are involved in a wide range of physiological functions, including the regulation of mechanosensation, cell polarity, cell proliferation, and apoptosis. In particular, PC2 assembles with chaperone proteins to form polycystic protein complexes that affect Ca2+ transport in cell membranes, cilia, endoplasmic reticulum, and mitochondria, and are involved in activating cell fate-related signaling pathways, particularly cell differentiation, proliferation, survival, and apoptosis, and more recently, autophagy. This leads to a shift of cystic cells from a normal uptake, quiescent state to a pathologically secreted, proliferative state. In conclusion, the complex structural and functional roles of PC2 highlight its critical importance in the pathogenesis of ADPKD, making it a promising target for therapeutic intervention.

2.
International Eye Science ; (12): 508-514, 2024.
Article de Chinois | WPRIM | ID: wpr-1012812

RÉSUMÉ

AIM: To investigate the effect of inhibiting Ca2+/calmodulin-dependent protein kinase Ⅱ(CAMKⅡ)expression in adult retinal pigment epithelial cell line-19(ARPE-19)cells on the migration, invasion, and tube formation of human umbilical vein endothelial cells(HUVECs)in a non-contact co-culture system.METHODS: RNA sequencing was performed on ARPE-19 cells overexpressing CAMKⅡ-δ, and bioinformatics was used to analyze the biological functions of the differentially expressed genes. Transwell inserts was used to construct a non-contact co-culture system of ARPE-19 and HUVECs. The experimental groups included: blank group: only HUVECs were inoculated without ARPE-19 cells; control group: ARPE-19 and HUVECs cells were co-cultured with complete medium; AIP group(CAMKⅡ inhibition group): ARPE-19 cells in AIP(160 nmol/L)were co-cultured with HUVECs in complete medium. The migration, invasion and tube formation abilities of HUVECs were detected. The protein expression levels of CAMKⅡ/AMPK/mTOR/VEGFA were detected by Western blotting.RESULTS:Bioinformatics analysis found that the differentially expressed genes could affect biological processes such as cell growth and death and cell movement. The scratch test and transwell migration test showed that the relative mobility of HUVECs in the AIP group was significantly lower than that in the control group(all P<0.05). However, the invasion and tube formation assay showed that the relative invasion rate and tube formation rate of the AIP group were not significantly different from those of the control group(both P>0.05). Western blotting results showed that the expression levels of CAMKⅡ, P-mTOR, and VEGFA proteins in the AIP group were significantly lower than those in the control group, while the expression level of the P-AMPK protein was significantly higher than that in the control group(all P<0.05).CONCLUSION:In the non-contact co-culture system, inhibition of CAMKⅡ expression in ARPE-19 cells significantly reduced the migration ability of HUVECs, but it cannot change the invasion and tube formation ability, which may be achieved by AMPK/mTOR/VEGFA.

3.
Biol. Res ; 572024.
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1564034

RÉSUMÉ

Background Astrocytes Ca2+ signaling play a central role in the modulation of neuronal function. Activation of metabotropic glutamate receptors (mGluR) by glutamate released during an increase in synaptic activity triggers coordinated Ca2+ signals in astrocytes. Importantly, astrocytes express the Ca2+-dependent nitric oxide (NO)-synthe-tizing enzymes eNOS and nNOS, which might contribute to the Ca2+ signals by triggering Ca2+ influx or ATP release through the activation of connexin 43 (Cx43) hemichannels, pannexin-1 (Panx-1) channels or Ca2+ homeostasis modulator 1 (CALHM1) channels. Hence, we aim to evaluate the participation of NO in the astrocytic Ca2+ signaling initiated by stimulation of mGluR in primary cultures of astrocytes from rat brain cortex. Results Astrocytes were stimulated with glutamate or t-ACPD and NO-dependent changes in [Ca2+]i and ATP release were evaluated. In addition, the activity of Cx43 hemichannels, Panx-1 channels and CALHM1 channels was also analyzed. The expression of Cx43, Panx-1 and CALHM1 in astrocytes was confirmed by immunofluorescence analysis and both glutamate and t-ACPD induced NO-mediated activation of CALHM1 channels via direct S-nitrosylation, which was further confirmed by assessing CALHM1-mediated current using the two-electrode voltage clamp technique in Xenopus oocytes. Pharmacological blockade or siRNA-mediated inhibition of CALHM1 expression revealed that the opening of these channels provides a pathway for ATP release and the subsequent purinergic receptordependent activation of Cx43 hemichannels and Panx-1 channels, which further contributes to the astrocytic Ca2+ signaling. Conclusions Our findings demonstrate that activation of CALHM1 channels through NO-mediated S-nitrosylation in astrocytes in vitro is critical for the generation of glutamate-initiated astrocytic Ca2+ signaling.

4.
Clinics ; Clinics;79: 100363, 2024. tab, graf
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1564332

RÉSUMÉ

Abstract Objective This study aimed to investigate the effect of Esketamine (ESK) on the Hypoxia/Reoxygenation (H/R) injury of cardiomyocytes by regulating TRPV1 and inhibiting the concentration of intracellular Ca2+. Methods The H/R injury model of H9c2 cardiomyocytes was established after 4h hypoxia and 6h reoxygenation. H9c2 cells were treated with different concentrations of ESK or TRPV1 agonist capsaicin (10 μM) or TRPV1 inhibitor capsazepine (1 μM). Cell viability was detected by CCK-8 method, and apoptosis by flow cytometry. Intracellular Ca2+ concentration was evaluated by Fluo-4 AM. LDH, MDA, SOD, and GSH-Px were detected with corresponding commercial kits. TRPV1 and p-TRPV1 proteins were detected by Western blot. Results After H/R, H9c2 cell viability decreased, apoptosis increased, intracellular Ca2+ concentration increased, LDH and MDA levels increased, SOD and GSH-Px levels decreased, and p-TRPV1 expression increased. ESK treatment rescued these changes induced by H/R. After up-regulating TRPV1, the protective effect of ESK on H/R injury of H9c2 cells was weakened, while down-regulating TRPV1 could further protect against H/R injury. Conclusion ESK alleviates H/R injury of cardiomyocytes by regulating TRPV1 expression and inhibiting intracellular Ca2+ concentration.

5.
Article de Chinois | WPRIM | ID: wpr-1005745

RÉSUMÉ

【Objective】 To observe the effect of puerarin on the concentration of Ca2+ and the expression of brain derived neurotrophic factor (BDNF) in hippocampal neurons of vascular dementia (VD) rats so as to explore the mechanism of puerarin in protecting nerve cells. 【Methods】 Male SD rats were randomly divided into sham operation group, model group, and puerarin intervention group. The vascular dementia model was established by ligating bilateral common carotid arteries at intervals of 3 days. Two weeks after the operation, the learning and memory abilities of the rats were evaluated by Morris water maze, and the expression of BDNF in the hippocampus of the rats was detected by immunohistochemistry and Western blotting. The mean fluorescence intensity was measured by flow cytometry to represent the intracellular free Ca2+ concentration. 【Results】 In the puerarin intervention group, the rats’ escape latency in Morris water maze was significantly shortened, the expression of BDNF in the hippocampus was significantly increased, and the concentration of Ca2+ in hippocampal neurons was decreased. Compared with the model group, the difference was statistically significant (all P<0.05). 【Conclusion】 Puerarin has neuroprotective effect on VD rats, and its mechanism may be related to the decrease of Ca2+ concentration in hippocampal neurons and the up-regulation of BDNF expression.

6.
Digital Chinese Medicine ; (4): 121-135, 2023.
Article de Anglais | WPRIM | ID: wpr-987633

RÉSUMÉ

@#【Objective】   As the main active ingredient of Tibetan medicine Hongjingtian (Rhodiolae Crenulatae Radix et Rhizoma), salidroside (Sal) has a good anti-apoptotic potential. Currently, there are some conflicting results on the anti-apoptotic mechanisms of Sal. Here we conducted a systematic review and meta-analysis to provide the preclinical evidence of its anti-apoptotic properties in preventing and treating hypoxic-ischemic cerebral damage(HICD). 【Methods】   The literature on the anti-apoptotic potential of Sal in the treatment of HICD from January 1, 1980 to November 9, 2021 was searched online using Chinese databases including Chinese National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP), and Wanfang Database, and English databases including PubMed and Web of Science. The quality of the included articles was evaluated by the Cochrane Collaboration network bias risk assessment criteria, and meta-analysis was performed using RevMan 5.3 software. 【Results】  A total of 40 articles were finally included. Among the 40 articles, 30 were about in vivo animal experiments and 17 about in vitro cell experiments, and 7 of them included both animal and cell experiments. After analysis, it was found that Sal had significant effects on disease-related indicators of HICD (P < 0.05), such as cerebral infarctsize and brain water content. As to in vivo studies, Sal mainly affects the expressions of apoptotic factors through antiinflammation, anti-oxidation, activation of complement pathway, and regulation of signal transduction and autophagy, thus exerting anti-apoptotic potential in treating HICD. While for in vitro studies, Sal plays the anti-apoptotic role in HICD models mainly through anti-oxidation, anti-inflammation, reduction of Ca2+ overload, regulation of mitochondrial function, signal transduction, and C3 complement. 【Conclusion】  Sal can take anti-apoptotic effects to prevent and treat HICD through mechanisms such as anti-inflammation, anti-oxidation, enhanced autophagy, complement and signal transduction, regulation of mitochondrial membrane potential, and reduction of Ca2 + overload.

7.
Zhongnan Daxue xuebao. Yixue ban ; (12): 641-647, 2023.
Article de Anglais | WPRIM | ID: wpr-982333

RÉSUMÉ

OBJECTIVES@#Application of ultrashort wave (USW) to rats with cerebral ischemia and reperfusion injury could inhibit the decrease of expression of secretory pathway Ca2+-ATPase 1 (SPCA1), an important participant in Golgi stress, reduce the damage of Golgi apparatus and the apoptosis of neuronal cells, thereby alleviating cerebral ischemia-reperfusion injury. This study aims to investigate the effect of USW on oxygen-glucose deprivation/reperfusion (OGD/R) injury and the expression of SPCA1 at the cellular level.@*METHODS@#N2a cells were randomly divided into a control (Con) group, an OGD/R group, and an USW group. The cells in the Con group were cultured without exposure to OGD. The cells in the OGD/R group were treated with OGD/R. The cells in the USW group were treated with USW after OGD/R. Cell morphology was observed under the inverted phase-contrast optical microscope, cell activity was detected by cell counting kit-8 (CCK-8), apoptosis was detected by flow cytometry, and SPCA1 expression was detected by Western blotting.@*RESULTS@#Most of the cells in the Con group showed spindle shape with a clear outline and good adhesion. In the OGD/R group, cells were wrinkled, with blurred outline, poor adhesion, and lots of suspended dead cells appeared; compared with the OGD/R group, the cell morphology and adherence were improved, with clearer outlines and fewer dead cells in the USW group. Compared with the Con group, the OGD/R group showed decreased cell activity, increased apoptotic rate, and down-regulating SPCA1 expression with significant differences (all P<0.001); compared with the OGD/R group, the USW group showed increased cell activity, decreased apoptotic rate, and up-regulating SPCA1 expression with significant differences (P<0.01 or P<0.001).@*CONCLUSIONS@#USW alleviates the injury of cellular OGD/R, and its protective effect may be related to its up-regulation of SPCA1 expression.


Sujet(s)
Animaux , Rats , Apoptose , Encéphalopathie ischémique , Glucose/métabolisme , Oxygène/métabolisme , Lésion d'ischémie-reperfusion/métabolisme , Activation de la transcription , Régulation positive , Calcium-Transporting ATPases/métabolisme
8.
Neuroscience Bulletin ; (6): 717-730, 2023.
Article de Anglais | WPRIM | ID: wpr-982418

RÉSUMÉ

Animal survival necessitates adaptive behaviors in volatile environmental contexts. Virtual reality (VR) technology is instrumental to study the neural mechanisms underlying behaviors modulated by environmental context by simulating the real world with maximized control of contextual elements. Yet current VR tools for rodents have limited flexibility and performance (e.g., frame rate) for context-dependent cognitive research. Here, we describe a high-performance VR platform with which to study contextual behaviors immersed in editable virtual contexts. This platform was assembled from modular hardware and custom-written software with flexibility and upgradability. Using this platform, we trained mice to perform context-dependent cognitive tasks with rules ranging from discrimination to delayed-sample-to-match while recording from thousands of hippocampal place cells. By precise manipulations of context elements, we found that the context recognition was intact with partial context elements, but impaired by exchanges of context elements. Collectively, our work establishes a configurable VR platform with which to investigate context-dependent cognition with large-scale neural recording.


Sujet(s)
Animaux , Souris , Rodentia , Réalité de synthèse , Cognition , 35416
9.
Neuroscience Bulletin ; (6): 602-616, 2023.
Article de Anglais | WPRIM | ID: wpr-982426

RÉSUMÉ

Methcathinone (MCAT) belongs to the designer drugs called synthetic cathinones, which are abused worldwide for recreational purposes. It has strong stimulant effects, including enhanced euphoria, sensation, alertness, and empathy. However, little is known about how MCAT modulates neuronal activity in vivo. Here, we evaluated the effect of MCAT on neuronal activity with a series of functional approaches. C-Fos immunostaining showed that MCAT increased the number of activated neurons by 6-fold, especially in sensory and motor cortices, striatum, and midbrain motor nuclei. In vivo single-unit recording and two-photon Ca2+ imaging revealed that a large proportion of neurons increased spiking activity upon MCAT administration. Notably, MCAT induced a strong de-correlation of population activity and increased trial-to-trial reliability, specifically during a natural movie stimulus. It improved the information-processing efficiency by enhancing the single-neuron coding capacity, suggesting a cortical network mechanism of the enhanced perception produced by psychoactive stimulants.


Sujet(s)
Souris , Animaux , Reproductibilité des résultats , Neurones , Sensation , Perception
10.
Frontiers of Medicine ; (4): 263-274, 2023.
Article de Anglais | WPRIM | ID: wpr-982570

RÉSUMÉ

Melanoma is the most aggressive cutaneous tumor. Neuropilin and tolloid-like 2 (NETO2) is closely related to tumorigenesis. However, the functional significance of NETO2 in melanoma progression remains unclear. Herein, we found that NETO2 expression was augmented in melanoma clinical tissues and associated with poor prognosis in melanoma patients. Disrupting NETO2 expression markedly inhibited melanoma proliferation, malignant growth, migration, and invasion by downregulating the levels of calcium ions (Ca2+) and the expression of key genes involved in the calcium signaling pathway. By contrast, NETO2 overexpression had the opposite effects. Importantly, pharmacological inhibition of CaMKII/CREB activity with the CaMKII inhibitor KN93 suppressed NETO2-induced proliferation and melanoma metastasis. Overall, this study uncovered the crucial role of NETO2-mediated regulation in melanoma progression, indicating that targeting NETO2 may effectively improve melanoma treatment.


Sujet(s)
Humains , Calcium-Calmodulin-Dependent Protein Kinase Type 2/métabolisme , Lignée cellulaire tumorale , Prolifération cellulaire , Mélanome/génétique , Protéines membranaires/génétique , Phosphorylation , Transduction du signal
11.
The Journal of Practical Medicine ; (24): 2750-2753, 2023.
Article de Chinois | WPRIM | ID: wpr-1020631

RÉSUMÉ

Objective To explore the molecular mechanism of prolonged atrial repolarization in rats with reperfusion atrial arrhythmia.Methods Sixteen Langendorff isolated heart perfusion models made by male SD rats were randomly divided into control group(group C,n = 8)and hypothermic ischemia-reperfusion group(group IR,n = 8).According to the occurrence of atrial arrhythmia after reperfusion,group IR was further subdivided into reperfusion non-atrial arrhythmia subgroup(group N-RAA)and reperfusion atrial arrhythmia subgroup(group R-AA).Group C was perfused with 37℃K-H solution for 120 min.In group IR,the isolated heart was perfused with 37℃K-H solution for 30 min and stopped,and the isolated heart was perfused with 4℃Thomas solution(20 mL/kg)for 60 mins.When the heart stopped for 30 mins,the isolated heart was perfused with a half dose of 4℃Thomas solution(10℃).During cardioplegia,the isolated heart was protected by low temperature Thomas solution(4℃),and then reperfused for 30 mins with 37℃K-H solution.The monophasic action potential(MAP)of the right atrium was recorded at balanced perfusion for 30 mins(T0),balanced perfusion for 105 mins in group C/reperfusion for 15 mins in group IR(T1)and balanced perfusion for 120 mins in group C/reperfusion for 30 min in group IR(T2);The duration of 50%and 90%repolarization of monophasic action potential(MAPD50 and MAPD90)was measured.After electrophysiological monitoring,the expression of Kir2.1 and CaMKⅡ in right atrium was detected by Western blot.Results Compared with T0,MAPD50 and MAPD90 at T1 and T2 were significantly prolonged in group R-AA(P<0.05),and MAPD90 at T1 and T2 in group R-NAA and group R-AA were significantly longer than those in group C(P<0.05).Compared with group R-NAA,MAPD50 and MAPD90 in group R-AA were significantly prolonged at T1 and T2(P<0.05).The results of Western blot showed that the expression of Kir2.1 in group R-NAA and group R-AA was significantly lower than that in group C(P<0.05),and that in group R-AA was significantly lower than that in group R-NAA(P<0.05).The expression of CaMKⅡ in group R-NAA and group R-AA was significantly higher than that in group C(P<0.05),and the expression of CaMKⅡ in group R-AA was significantly higher than that in group R-NAA.Conclusion The prolonged duration of atrial repolarization in rats with hypothermic ischemia-reperfusion atrial arrhythmia may be related to the down-regulation of Kir2.1 expression and the up-regulation of CaMKⅡ expression.

12.
Frontiers of Medicine ; (4): 1219-1235, 2023.
Article de Anglais | WPRIM | ID: wpr-1010811

RÉSUMÉ

Heart failure with preserved ejection fraction (HFpEF) displays normal or near-normal left ventricular ejection fraction, diastolic dysfunction, cardiac hypertrophy, and poor exercise capacity. Berberine, an isoquinoline alkaloid, possesses cardiovascular benefits. Adult male mice were assigned to chow or high-fat diet with L-NAME ("two-hit" model) for 15 weeks. Diastolic function was assessed using echocardiography and noninvasive Doppler technique. Myocardial morphology, mitochondrial ultrastructure, and cardiomyocyte mechanical properties were evaluated. Proteomics analysis, autophagic flux, and intracellular Ca2+ were also assessed in chow and HFpEF mice. The results show exercise intolerance and cardiac diastolic dysfunction in "two-hit"-induced HFpEF model, in which unfavorable geometric changes such as increased cell size, interstitial fibrosis, and mitochondrial swelling occurred in the myocardium. Diastolic dysfunction was indicated by the elevated E value, mitral E/A ratio, and E/e' ratio, decreased e' value and maximal velocity of re-lengthening (-dL/dt), and prolonged re-lengthening in HFpEF mice. The effects of these processes were alleviated by berberine. Moreover, berberine ameliorated autophagic flux, alleviated Drp1 mitochondrial localization, mitochondrial Ca2+ overload and fragmentation, and promoted intracellular Ca2+ reuptake into sarcoplasmic reticulum by regulating phospholamban and SERCA2a. Finally, berberine alleviated diastolic dysfunction in "two-hit" diet-induced HFpEF model possibly because of the promotion of autophagic flux, inhibition of mitochondrial fragmentation, and cytosolic Ca2+ overload.


Sujet(s)
Mâle , Souris , Animaux , Défaillance cardiaque/traitement médicamenteux , Débit systolique/physiologie , Fonction ventriculaire gauche/physiologie , Berbérine/usage thérapeutique , Modèles animaux de maladie humaine , Dynamique mitochondriale , Myocarde , Homéostasie
13.
Article de Chinois | WPRIM | ID: wpr-1024479

RÉSUMÉ

Objectives:To establish a model of Mycobacterium tuberculosis infection of osteoclasts(OC)and explore the mechanism of Mycobacterium tuberculosis infection on OC.Methods:Peripheral blood mononuclear cells(peripheral blood mononuclear cells,PBMCs)were isolated from healthy volunteers.Receptor activator of nuclear factor-KB ligand(RANKL)and macrophage-colony stimulating factor(M-CSF)were used to make PBMCS into OC,and tartrate resistant acid phosphatase(TRAP)staining was performed on the cells.The constructed kanamycin resistant H37Rv pMV261-GFP green fluorescent strain was resuscitated and cultured with 10%oleic albumin dextrose catalase(OADC),7H9 and kanamycin containing Mycobacterium tuberculosis special liquid medium in an incubator at 37℃ until the optical density(OD)value was about 0.5 at 600nm.The OC cells cultured alone were set as the blank control group.And OC cells were also infected with Mycobacterium tuberculosis at different multiplicity of infection(MOI)for 24h,and MTT colorimetric method was used to detect cell survival rate.The MOI with the highest cell survival rate was selected as experimental MOI,and OC cells infected with H37Rv at experimental MOI were set as the experimental group.Fluorescence microscopy and Mycobacterium tuberculosis acid-fast staining were used to observe the transfection of Mycobacterium tuberculosis at the experimental MOI.Quantitative real-time PCR(qRT-PCR)was used to detect the expressions of non-receptor tyrosine kinase C-src,cathepsin K(CK),carbonic anhydrase 2(CA2),Integrin-β3 and matrix metalloproteinase-9(MMP-9).Immunohistochemistry was used to detect the expressions of P-src,CK,CA2,Integrin-β3 and MMP-9 on the cell surface.Western blot(WB)was used to detect the protein expression levels of P-src,CK,CA2,Integrin-β3,and MMP-9.Results:TRAP staining showed that more than 90%of the cells were OC after 15d of culture,which could be used for experiments.The results of MTT colorimetric assay showed that the cell survival rate was the highest when the MOI was 20:1(P<0.05).This transfection multiplicity can be used as the concentration of experimental group.Fluorescence microscopy showed that when the transfection multiplicity ratio was 20:1,the green fluorescent Mycobacterium tuberculosis entered the OC and was successfully transfected into the OC.The results of acid-fast staining after infection of OC with Mycobacterium tuberculosis showed that when the MOI was 20:1,the acid-fast Mycobacterium tuberculosis stained red entered OC and was also successfully transfected into OC.The results of qRT-PCR,cell immunohistochemistry,and WB showed that the expressions of MMP-9,CK,C-src,CA2,and Integrin-β3 in the experimental group were higher than those in the blank control group(P<0.05).Conclusions:Mycobacterium tuberculosis can transfect OC;Compared with the blank control group,the levels of five bone destruction factors in the experimental group transfected with OC by Mycobacterium tuberculosis were increased,suggesting that bone destruction of spinal tuberculosis may be related to this,which may provide a new exploration direction for the diagnosis and treatment of bone tuberculosis diseases.

14.
Acta Pharmaceutica Sinica B ; (6): 3744-3755, 2023.
Article de Anglais | WPRIM | ID: wpr-1011141

RÉSUMÉ

The well-known insulin-like growth factor 1 (IGF1)/IGF-1 receptor (IGF-1R) signaling pathway is overexpressed in many tumors, and is thus an attractive target for cancer treatment. However, results have often been disappointing due to crosstalk with other signals. Here, we report that IGF-1R signaling stimulates the growth of hepatocellular carcinoma (HCC) cells through the translocation of IGF-1R into the ER to enhance sarco-endoplasmic reticulum calcium ATPase 2 (SERCA2) activity. In response to ligand binding, IGF-1Rβ is translocated into the ER by β-arrestin2 (β-arr2). Mass spectrometry analysis identified SERCA2 as a target of ER IGF-1Rβ. SERCA2 activity is heavily dependent on the increase in ER IGF-1Rβ levels. ER IGF-1Rβ phosphorylates SERCA2 on Tyr990 to enhance its activity. Mutation of SERCA2-Tyr990 disrupted the interaction of ER IGF-1Rβ with SERCA2, and therefore ER IGF-1Rβ failed to promote SERCA2 activity. The enhancement of SERCA2 activity triggered Ca2+ER perturbation, leading to an increase in autophagy. Thapsigargin blocked the interaction between SERCA2 and ER IGF-1Rβ and therefore SERCA2 activity, resulting in inhibition of HCC growth. In conclusion, the translocation of IGF-1R into the ER triggers Ca2+ER perturbation by enhancing SERCA2 activity through phosphorylating Tyr990 in HCC.

15.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;56: e11879, 2023. tab, graf
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1420747

RÉSUMÉ

The expression of T-type voltage-dependent Ca2+ channels (Cav3) has been previously observed in breast cancer, but their expression and subcellular localization were not evaluated in pre-neoplastic lesions. Therefore, this work aimed to evaluate protein expression and subcellular localization of T-type channel isoforms in human breast tissue samples. Protein expressions of CaV3.1, CaV3.2, and CaV3.3 were evaluated by immunohistochemistry in breast without alteration, in proliferative non-neoplastic lesions, and in neoplastic ductal epithelial lesions of the human breast. CaV3.1, CaV3.2, and CaV3.3 nuclear expressions were decreased in advanced stages of neoplastic transformation, whereas CaV3.1 and CaV3.2 cytoplasmic expression increased. Also, the decrease in nuclear expression was correlated with an increase in cytoplasmic expression for CaV3.1 isoform. The change in CaV3 protein expression and subcellular localization are consistent with the neoplastic transformation stages of mammary epithelial cells, evident in early neoplastic lesions, such as ductal carcinomas in situ. These results suggest a possible involvement of CaV3 in the carcinogenic processes and could be considered as a potential pharmacological target in new therapies for breast cancer treatment.

16.
Article | IMSEAR | ID: sea-218716

RÉSUMÉ

Synthesis and characterization of halosulphate-based phosphors is important for thermoluminescence dosimetry (TLD), radiophotoluminescence dosimetry (RPL) and scintillator materials. The enhancement of luminescence output in halosulphate-based phosphors and it may be useful for lamp, solid-state lamp and radiation. Dosimetry by activator as well as sensitizer are well known properties. The combustion technique is not applicable for the synthesis of TLD phosphors due to very fine particles, which show less TL intensity, while sol-gel, solid-state diffusion, melt method and precipitation methods are applicable for TLD phosphors. Two halosulphates namely Na21( SO4 ) 7 F6 Cl and 2K3Ca2(SO4)3F were prepared and doped with Dy and Tm for different concentration .Halosulphate , Na21( SO4 ) 7 F6 Cl was prepared by wet chemical method and Halosulphate , 2K3Ca2(SO4)3F was prepared by solid state diffusion method . The characterization was done by X - ray diffraction ( XRD ) , Thermo luminescence (TL) was also studied . For Dy doped Na21( SO4) 7 F6 Cl , The peak was observed at 1200 C and shoulder at 1750C for 0.2 % molar concentration of Dy. and for 2K3Ca2(SO4)3F doped with Tm the shoulder peak was observed at 240 0 C and at 150 0C for 0.7 % molar concentration of Tm.

17.
Invest. clín ; Invest. clín;63(3): 243-261, set. 2022. tab, graf
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1534661

RÉSUMÉ

Abstract Tetrahydroquinoline derivatives are interesting structures exhibiting a wide range of biological activities, including antitumor effects. In this investigation, the effect of the synthesized tetrahydroquinolines JS-56 and JS-92 on apoptosis, intracellular Ca2+ concentration ([Ca2+]i), and the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) activity was determined on MCF-7 breast cancer cells. Colorimetric assays were used to assess MCF-7 cells viability and SERCA activity. Fura-2 and rhodamine 123 were used to measure the intracellular Ca2+ concentration and the mitochondrial electrochemical potential, respec tively. TUNEL assay was used to analyze DNA fragmentation, while caspase activity and NF-κB-dependent gene expression were assessed by luminescence. In silico models were used for molecular docking analysis. These compounds increase intracellular Ca2+ concentration; the main contribution is the Ca2+ entry from the extracellular milieu. Both JS-56 and JS-92 inhibit the activity of SERCA and dissipate the mitochondrial electrochemical potential through processes dependent and independent of the Ca2+ uptake by this organelle. Furthermore, JS-56 and JS-92 generate cytotoxicity in MCF-7 cells. The effect of JS-92 is higher than JS-56. Both compounds activate caspases 7 and 9, cause DNA fragmentation, and potentiate the effect of phorbol 12-myristate-13-acetate on NF-κB-dependent gene expression. Molecular docking analysis suggests that both compounds have a high interaction for SERCA, similar to thapsigargin. Both tetrahydroquinoline derivatives induced cell death through a combination of apoptotic events, increase [Ca2+]i, and inhibit SERCA activity by direct interaction.


Resumen Los derivados de tetrahidroquinolina son estructuras interesantes que exhiben una amplia gama de actividades biológicas, incluyendo efectos antitumorales. Se determinó el efecto de las tetrahidroquinolinas sintetizadas JS-56 y JS-92 sobre la apoptosis, concentración intracelular de Ca2+ ([Ca2+]i) y la actividad Ca2+-ATPasa del retículo sarco(endo)plásmico (SERCA) en células de cáncer de mama MCF-7. Se usaron ensayos colorimétricos para evaluar la viabilidad de las células MCF-7 y la actividad SERCA. Se emplearon Fura-2 y rodamina 123 para medir la concentración de Ca2+ intracelular y el potencial electroquímico mitocondrial, respectivamente. El ensayo TUNEL se utilizó para analizar la fragmentación del ADN, mientras que la actividad de caspasas y la expresión génica dependiente de NF-κB se evaluaron mediante luminiscencia. Modelos in silico permitieron el análisis del acoplamiento molecular. Estos compuestos aumentan la concentración de Ca2+ intracelular; la principal contribución es la entrada de Ca2+ desde el medio extracelular. Tanto JS-56 como JS-92 inhiben la actividad de SERCA y disipan el potencial electroquímico mitocondrial a través de procesos dependientes e independientes de la captación de Ca2+ por este orgánulo. Además, JS-56 y JS-92 generan citotoxicidad en células MCF-7. El efecto de JS-92 es mayor que JS-56. Ambos compuestos activan las caspasas 7 y 9, provocan la fragmentación del ADN y potencian el efecto del 12-miristato-13-acetato de forbol en la expresión génica dependiente de NF-κB. El análisis de acoplamiento molecular sugiere que ambos compuestos tienen una alta interacción con SERCA, similar a la tapsigargina. Ambos derivados de tetrahidroquinolina indujeron la muerte celular a través de una combinación de eventos apoptóticos, aumento de [Ca2+]i e inhibición de la actividad SERCA por interacción directa.

18.
Indian J Exp Biol ; 2022 Jan; 60(1): 34-40
Article | IMSEAR | ID: sea-222490

RÉSUMÉ

Scutellaria baicalensis Georgi, locally known as HuangQin, and commonly as Baikal or Chinese skullcap, is an important herb in Chinese traditional medicine. The flavonoids from this plant are main active substances responsible for its medicinal applications. Wogonin is one such active ingredient derived from this plant. Here, we investigated the mechanism of the vasodilation effect of wogonin on isolated rat thoracic aortas. For this study, endothelium intact and endothelium removed thoracic aortic rings were prepared from rats. Using a tension transducer, the tension of the rat thoracic aortic rings was recorded. Results showed that wogonin is able to relax the endothelium-intact aortic rings, but L-NAME, indomethacin (Indo), and methylene blue (MB) could not reduce the tension in these rings. Wogonin was also able to relax endotheliumremoved rings. However, treatment with tetraethylammonium (TEA), BaCl2, glibenclamide (Gly), 4-aminopyridine (4-AP), and verapamil (Ver) had no effect on vasodilation induced by wogonin. Using wogonin to pre-treat endothelium-removed aortic rings reduced the contraction induced by K+. Pre-treatment of endothelium-removed aortic rings with wogonin markedly reduced the contraction induced by 10-6 M PE in Ca2+-free solution. It could be concluded that L-type calcium channels and intracellular Ca2+ release is inhibited by wogonin.

19.
Chin. j. integr. med ; Chin. j. integr. med;(12): 319-329, 2022.
Article de Anglais | WPRIM | ID: wpr-928950

RÉSUMÉ

OBJECTIVE@#To explore the effect of Kuanxiong Aerosol (KXA) on isoproterenol (ISO)-induced myocardial injury in rat models.@*METHODS@#Totally 24 rats were radomly divided into control, ISO, KXA low-dose and high-dose groups according to the randomized block design method, and were administered by intragastric administration for 10 consecutive days, and on the 9th and 10th days, rats were injected with ISO for 2 consecutive days to construct an acute myocardial ischemia model to evaluate the improvement of myocardial ischemia by KXA. In addition, the diastolic effect of KXA on rat thoracic aorta and its regulation of ion channels were tested by in vitro vascular tension test. The influence of KXA on the expression of calcium-CaM-dependent protein kinase II (CaMK II)/extracellular regulated protein kinases (ERK) signaling pathway has also been tested.@*RESULTS@#KXA significantly reduced the ISO-induced increase in ST-segment, interventricular septal thickness, cardiac mass index and cardiac tissue pathological changes in rats. Moreover, the relaxation of isolated thoracic arterial rings that had been precontracted using norepinephrine (NE) or potassium chloride (KCl) was increased after KXA treatment in an endothelium-independent manner, and was attenuated by preincubation with verapamil, but not with tetraethylammonium chloride, 4-aminopyridine, glibenclamide, or barium chloride. KXA pretreatment attenuated vasoconstriction induced by CaCl2 in Ca2+-free solutions containing K+ or NE. In addition, KXA pretreatment inhibited accumulation of Ca2+ in A7r5 cells mediated by KCl and NE and significantly decreased p-CaMK II and p-ERK levels.@*CONCLUSION@#KXA may inhibit influx and release of calcium and activate the CaMK II/ERK signaling pathway to produce vasodilatory effects, thereby improving myocardial injury.


Sujet(s)
Animaux , Rats , Aérosols , Aorte thoracique , Calcium/métabolisme , Endothélium vasculaire/métabolisme , Ischémie myocardique/métabolisme , Vasodilatation
20.
Neuroscience Bulletin ; (6): 474-488, 2022.
Article de Anglais | WPRIM | ID: wpr-929086

RÉSUMÉ

Astrocytes are increasingly recognized to play an active role in learning and memory, but whether neural inputs can trigger event-specific astrocytic Ca2+ dynamics in real time to participate in working memory remains unclear due to the difficulties in directly monitoring astrocytic Ca2+ dynamics in animals performing tasks. Here, using fiber photometry, we showed that population astrocytic Ca2+ dynamics in the hippocampus were gated by sensory inputs (centered at the turning point of the T-maze) and modified by the reward delivery during the encoding and retrieval phases. Notably, there was a strong inter-locked and antagonistic relationship between the astrocytic and neuronal Ca2+ dynamics with a 3-s phase difference. Furthermore, there was a robust synchronization of astrocytic Ca2+ at the population level among the hippocampus, medial prefrontal cortex, and striatum. The inter-locked, bidirectional communication between astrocytes and neurons at the population level may contribute to the modulation of information processing in working memory.


Sujet(s)
Animaux , Humains , Souris , Astrocytes , Hippocampe/physiologie , Mémoire à court terme/physiologie , Neurones/physiologie , Dynamique des populations
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE