ABSTRACT
Introdução: O câncer de pele não melanoma compeende grupo de neoplasias com alta incidência na população mundial. É dividido em carcinoma basocelular e de células escamosas. Por ser de grande prevalência, entender o processo de oncogênese e a relação com íons, proteínas e receptores celulares no câncer de pele não melanoma pode contribuir para que novas terapêuticas sejam avaliadas. Objetivo: Entender o processo da oncogênese dos tumores de pele não melanomas e sua relação com a imunolocalização do IP3R. Métodos: Revisão integrativa da literatura com síntese de evidências. A base de dados foi o PubMed; a estratégia de busca: "carcinoma espinocelular, AND/ OR carcinoma basocelular, AND/OR IP3R, AND/OR imunoistoquímica". Foram considerados para revisão os trabalhos publicados entre 2018 e 2023. Foram incluídos 40 trabalhos, integralmente lidos e resumidos. Resultados: Câncer de pele não melanoma são os tumores malignos mais comuns em todo o mundo, sendo 75-80% o carcinoma basocelular, e até 25% o de células escamosas. As interações moleculares de forma geral, envolvem grande participação de moléculas supressoras tumorais, assim como de procto-oncogenes. Além disso, canais iônicos voltagem dependente controlam o fluxo citosólico de íons, dentre eles o cálcio. O IP3R (receptor do fosfatidil inositol-3) permite a saída de cálcio do retículo endoplasmático para que seja utilizado pela célula para atividades fisiológias como proliferação, angiogênese, motilidade e capacidade de invasão. Conclusão: O IP3R, pelas características de expressão imunoistoquímica, parece estar relacionado também, à fisiopatologia do câncer de pele não melanoma.
Introduction: Non-melanoma skin cancer comprises a group of neoplasms with a high incidence in the world population. It is divided into basal cell carcinoma and squamous cell carcinoma. As it is highly prevalent, understanding the process of oncogenesis and the relationship with ions, proteins and cellular receptors in nonmelanoma skin cancer can contribute to the evaluation of new therapies. Objective: To understand the oncogenesis process of non-melanoma skin tumors and its relationship with the immunolocalization of IP3R. Methods: Integrative literature review with evidence synthesis. The database was PubMed; the search strategy: "squamous cell carcinoma, AND/OR basal cell carcinoma, AND/OR IP3R, AND/OR immunohistochemistry". Works published between 2018 and 2023 were considered for review; 40 works were included, fully read and summarized. Results: Non-melanoma skin cancer is the most common malignant tumor worldwide, with 75-80% being basal cell carcinoma, and up to 25% being cell carcinoma. Molecular interactions in general involve a large participation of tumor suppressor molecules, as well as procto-oncogenes. Furthermore, voltage-dependent ion channels control the cytosolic flow of ions, including calcium. The IP3R (phosphatidyl inositol-3 receptor) allows the exit of calcium from the endoplasmic reticulum so that it can be used by the cell for physiological activities such as proliferation, angiogenesis, motility and invasion capacity. Conclusion: The IP3R, due to its immunohistochemical expression characteristics, appears may also be related to the pathophysiology of nonmelanoma skin cancer.
ABSTRACT
【Objective】 To explore the roles of 1,4,5-trisphosphate receptor (IP3Rs) and ryanodine receptors (RyRs), the two main Ca2+ release channels in sarcoplasmic reticulum (SR), in the regulation of intracellular Ca2+ oscillations in neonatal rat cardiomyocytes (NRCMs). 【Methods】 We isolated and cultured NRCMs for different days, then loaded them with Ca2+ indicator fura-2 and performed real-time fluorescent imaging. To distinguish the effects of IP3Rs and RyRs, NRCMs were pre-treated with phenylephrine (PE, IP3Rs agonist), caffeine (RyRs agonist), 2-APB (IP3Rs antagonist), and tetracaine (RyRs antagonists), respectively. 【Results】 The cultured monolayer NRCMs showed spontaneous synchronized Ca2+ oscillations. PE activation or 2-APB blockade of IP3Rs increased or reduced the frequency of Ca2+ oscillations in NRCMs, accordingly, with no significant effect on the amplitude of Ca2+ oscillations. Activation of RyRs with caffeine increased the frequency of Ca2+ oscillations, but unsynchronized the intercellular rhythm of calcium release and beating pace, while blocking RyRs with tetracaine completely abolished the Ca2+ oscillations and beats in NRCMs. In addition, the effect of PE stimulation on Ca2+ oscillation frequency gradually decreased along with cultured days. 【Conclusion】 IP3Rs regulate the rhythm of calcium oscillations, whereas RyRs are the main channel for bulky store Ca2+ release.
ABSTRACT
ABSTRACT Large conductance calcium-activated potassium (BK) channels carry out many functions in the central nervous system. These channels open in response to increased cytosolic calcium ([Ca2+]cyt) concentration. The influx of calcium ions to the cytosol can occur through voltage-gated calcium channels (VGCCs) on the plasma membrane and/ or through IP3 receptors (IP3-Rs) and ryanodine receptors (RyRs) on the endoplasmic reticulum membrane. The BK channel/IP3-R/RyR interaction has been widely reported in smooth muscle but scarcely investigated in relation to neurons. The aim of this study was to theoretically explore the function of the BK/IP3-R complex by means of a computational model of a neuron that replicates the interaction between the release of Ca2+ from the endoplasmic reticulum (through IP3-Rs) and the opening of the BK channels. The mathematical models are based on the Hodgkin-Huxley formalism and the Goldbeter model. These models were implemented on Visual Basic® and differential equations were solved numerically. Distinct conditions were contemplated for BK conductance and the efflux of endoplasmic Ca2+ to the cytosol. An abrupt rise in [Ca2+]cyt (≥ 5 μM) and short duration (spark) was found to activate BK channels and either pause or stop the action potential train.
RESUMEN Los canales de potasio activados por calcio de gran conductancia (canales BK) cumplen múltiples funciones en el sistema nervioso central. Estos canales se abren en respuesta al incremento de la concentración de calcio citosólico ([Ca2+]cyt). La entrada de Ca2+ puede ocurrir a través de canales de calcio dependientes de voltaje (VGCCs) localizados en la membrana plasmática y por eflujo de Ca2+ del retículo endoplásmico (ER) causado por 1,4,5-Trifosfato (IP3) o rianodina (RyR). La interacción BK/IP3/RyR ha sido ampliamente estudiada en músculo liso, pero escasamente en neuronas. El objetivo de este estudio fue explorar teóricamente la función del complejo BK/IP3-R mediante un modelo computacional de una neurona que replica la interacción entre la liberación de Ca2+ del retículo endoplásmico (a través de IP3-Rs) y la apertura de los canales BK. Los modelos matemáticos se basan en el formalismo de Hodgkin-Huxley y el modelo de Goldbeter. Estos modelos fueron implementados en Visual Basic® y las ecuaciones diferenciales fueron resueltas por métodos numéricos. Se contemplaron distintas condiciones para la conductancia del canal BK y la salida de Ca2+ endoplásmico al citosol. Los resultados muestran que un incremento abrupto de [Ca2+] cyt (≥ 5 μM) y de corta duración (spark) activa los canales BK y producen una pausa o detiene el tren de potenciales de acción.
ABSTRACT
Food deprivation can rescue obesity and overweight-induced mood disorders, and promote mood performance in normal subjects. Animal studies and clinical research have revealed the antidepressant-like effect of calorie restriction, but little is known about the mechanism of calorie restriction-induced mood modification. Previous studies have found that astrocytes modulate depressive-like behaviors. Inositol 1,4,5-trisphosphate receptor type 2 (IP3R2) is the predominant isoform in mediating astrocyte Ca
Subject(s)
Animals , Mice , Adenosine Triphosphate , Antidepressive Agents/therapeutic use , Caloric Restriction , Mice, Knockout , Prefrontal CortexABSTRACT
Food deprivation can rescue obesity and overweight-induced mood disorders, and promote mood performance in normal subjects. Animal studies and clinical research have revealed the antidepressant-like effect of calorie restriction, but little is known about the mechanism of calorie restriction-induced mood modification. Previous studies have found that astrocytes modulate depressive-like behaviors. Inositol 1,4,5-trisphosphate receptor type 2 (IP3R2) is the predominant isoform in mediating astrocyte Ca
ABSTRACT
Huangpu Tongqiao Capsules(HPTQC), with the functions of invigorating Qi and kidney, eliminating phlegm and removing blood stasis, have the effect of treating Alzheimer's disease(AD), but its mechanism needs further exploration. To explore the relationship between the therapeutic mechanism of HPTQC on Alzheimer's disease and EGFR-PLCγ signal pathway, 40 healthy male SD rats were selected and divided into 4 groups randomly: sham operation group(sham), model group(model), HPTQC group(HPTQC), and nimodipine group(NMP). AD rat model was established by intraperitoneal injection of D-galactose combined with an intracerebral injection of amyloid-β peptide(25-35). After 28 days of administration, Morris water maze test and HE staining showed that the learning and memory ability of AD rats were significantly decreased(P<0.01), and hippocampal neurons were obviously da-maged. However, HPTQC could improve the learning and memory ability of AD rats(P<0.05) and reduce the damage of hippocampal neurons. Immunofluorescence test results showed that the expression levels of EGFR and p-Tau in hippocampal CA1 region of AD rats were significantly increased(P<0.01), and HPTQC could reduce the expression of EGFR and p-Tau in hippocampus of AD rats(P<0.01). Western blot results showed that the protein expression levels of EGFR, PLCγ, IP3 R and p-Tau in hippocampus of AD rats were significantly increased(P<0.01), and HPTQC could reduce the protein expression of EGFR, PLCγ, IP3 R and p-Tau in AD rats(P<0.05). RT-PCR results showed that the mRNA levels of EGFR, PLCγ, IP3 R and Tau in hippocampus of AD rats were significantly increased(P<0.01), and HPTQC could reduce the mRNA levels of EGFR, PLCγ, IP3 R and Tau in AD rats(P<0.05). The results indicate that HPTQC can improve the learning and memory ability of AD rats, and its mechanism of action may be related to regulating EGFR-PLCγ signal pathway.
Subject(s)
Animals , Male , Rats , Alzheimer Disease , Amyloid beta-Peptides , Capsules , Disease Models, Animal , ErbB Receptors , Hippocampus , Rats, Sprague-Dawley , Signal TransductionABSTRACT
Objective To observe the curative effect of 17β-estradiol on idiopathic ventricular arrhythmia (IVA) during peri-menopausal period and explore the association with IP3/Ryn expression of receptor-regulated calcium pool. Methods 32 cases IVA during peri-menopausal period (IVA group) and 32 cases healthy women during peri-menopausal period of the same levels of age (normal control group) were selected. The IVA group received oral 17β-estradiol for 2 months. The count of arrhythmia in IVA group was recorded, the IP3/Ryn 2 expression pre- and post-treatment in IVA group and normal control group were detected. Results Compared with pre-treatment, 17β-estradiol significantly reduced the occurrence of IVA (P<0.05). Compared with pre-treatment, 17β-estradiol significantly reduced IP3 expression(P<0.05), while there was no significant difference compared with normal control group. 17β-estradiol had no significant effect on Ryn 2 expression. Conclusion The anti-IVA effect of 17β-estradiol may be associated with the IP3 receptor gene expression.
ABSTRACT
Angiotensin converting enzyme (ACE) inhibitors therapy is aassociated with bothersome dry cough as an adverse effect. The mechanisms underlying this adverse effect are not clear. Therefore, influence of captopril (an ACE inhibitor) on acetylcholine (ACh)-induced bronchial smooth muscle contractions was investigated. Further, the mechanisms underlying the captopril-induced changes were also explored. In vitro contractions of rat bronchial smooth muscle to cumulative concentrations of ACh were recorded before and after exposure to captopril. Further, the involvement of kinin and inositol triphosphate (IP3) pathways for captopril-induced alterations were explored. ACh produced concentration-dependent (5-500 μM) increase in bronchial smooth muscle contractions. Pre-treatment with captopril augmented the ACh-induced contractions at each concentration significantly. Pre-treatment with aprotinin (kinin synthesis inhibitor) or heparin (inositol triphosphate, IP3-inhibitor), blocked the captopril-induced augmentation of bronchial smooth muscle contractions evoked by ACh. Further, captopril-induced augmentation was absent in calcium-free medium. These results suggest that captopril sensitizes bronchial smooth muscles to ACh-induced contractions. This sensitization may be responsible for dry cough associated with captopril therapy.
ABSTRACT
The worldwide increase in the use of antibiotics as an integral part of poultry and livestock production industry has recently received increasing attention as a contributory factor in the international emergence of antibiotic-resistant bacteria in human beings. To gauge the presence of the aforementioned scenario in the Indian context, a preliminary survey was conducted to assess the use of chlortetracycline (CTC) in 12 commercial layer farms and to quantify and confirm its residue in the egg. Samples of feed and eggs were collected at day 0 (prior to CTC addition), 3rd, 5th and 7th day during treatment and on the 9th and 14th day (2nd and 7th day after withdrawal of CTC) from each of the 12 commercial poultry farms studied. Concentration of CTC in feed was significantly (P<0.01) high on the 3rd, 5th and 7th day. On the 9th day and 14th day CTC concentration in feed was significantly (P<0.01) lower compared to the earlier 3 days studied. A highly significant difference (P<0.01) of the antibiotic residue in egg was observed in all the 5 days with high residual levels of CTC in egg. CTC in feed and its residue in egg were detected even on the 9th and 14th day respectively.
ABSTRACT
In this study, we prepared cordycepin-enriched (CE)-WIB801C, a n-butanol extract of Cordyceps militaris-hypha, and investigated the effect of CE-WIB801C on collagen-induced human platelet aggregation. CE-WIB801C dose-dependently inhibited collagen-induced platelet aggregation, and its IC50 value was 175 microg/ml. CE-WIB801C increased cAMP level more than cGMP level, but inhibited collagen-elevated [Ca2+]i mobilization and thromboxane A2 (TXA2) production. cAMP-dependent protein kinase (A-kinase) inhibitor Rp-8-Br-cAMPS increased the CE-WIB801C-downregulated [Ca2+]i level in a dose dependent manner, and strongly inhibited CE-WIB801C-induced inositol 1, 4, 5-trisphosphate receptor (IP3R) phosphorylation. These results suggest that the inhibition of [Ca2+]i mobilization by CE-WIB801C is resulted from the cAMP/A-kinase-dependent phosphorylation of IP3R. CE-WIB801C suppressed TXA2 production, but did not inhibit the activities of cyclooxygenase-1 (COX-1) and TXA2 synthase (TXAS). These results suggest that the inhibition of TXA2 production by WIB801C is not resulted from the direct inhibition of COX-1 and TXAS. In this study, we demonstrate that CE-WIB801C with cAMP-dependent Ca2+-antagonistic antiplatelet effects may have preventive or therapeutic potential for platelet aggregation-mediated diseases, such as thrombosis, myocardial infarction, atherosclerosis, and ischemic cerebrovascular disease.
Subject(s)
Humans , 1-Butanol , Atherosclerosis , Blood Platelets , Cordyceps , Cyclic AMP-Dependent Protein Kinases , Cyclooxygenase 1 , Inhibitory Concentration 50 , Inositol , Myocardial Infarction , Phosphorylation , Platelet Aggregation , Thrombosis , Thromboxane A2ABSTRACT
Objective To investigate the effects of specific protein 1 ( Sp1 ) on the TNF-αin-duced expression of inositol 1, 4, 5 trisphosphate receptor type 1 ( IP3R1 ) in human mesangial cells ( HMCs) and to further elucidate the molecular mechanism regarding the decreased glomerular filtration rate ( GFR ) during hepatorenal syndrome .Methods Quantitative real-time polymerase chain reaction and Western blot assay were used to analyze the effects of TNF-αon the expression of IP3R1 at mRNA level and the expression of IP3R1 and Sp1 at protein level in HMCs , respectively.HMCs were transfected with a re-combinant plasmid PGL3-IP3R1 promoter to determine the effects of TNF-αon the activity of IP3R1 promot-er.HMCs were treated with Mithramycin A , an inhibitor of Sp1 binding, and transfected with Sp1-siRNA plasmid respectively to evaluate the expression of IP 3R1 regulated by TNF-α.The role of TNFR1 and TNFR2 in the TNF-αinduced expression of Sp 1 and IP3R1 proteins were detected by Western blot .Results TNF-αincreased the expression of IP3R1 at mRNA level and the expression of IP3R1 and Sp1 at protein lev-el in HMCs.Moreover, the activity of IP3R1 promoter in HMCs was remarkably increased by TNF-αas well.TNF-αinduced expression of IP3R1 was inhibited by Mithramycin A in a concentration dependent manner.HMCs transfected with Sp1-siRNA plasmid showed a significantly decreased expression of IP 3R1 protein.Both anti-TNFR1 and anti-TNFR2 antibodies blocked the TNF-αinduced IP3R1 expression, while only anti-TNFR1 antibodies inhibited the TNF-αinduced Sp1 expression.Conclusion TNF-αmight in-crease the expression of IP3R1 through the TNFR1/Sp1 signaling pathways in HMCs .
ABSTRACT
Objective To explore the effects of TNF-α on the expression of IP33R1 mRNA and protein in human mesangial cells (HMCs) and elucidate the mechnism of TNF-α indnces the IP3R1 expression in the occurrence of hepatorenal syndrome (HRS).Methods HMCs was stimulated by tumor (TNF-α) with 100 ng/mL for different hours (2,4,8,24 hours).The expression change of IP3R1 mRNA and protein were detected by quantitative real-time polymerase chain reaction and immunoblot assay.Several inhibitors including D609,U73122,PP1,Safingol,Rottlerin and non-radioactive PKC assay to examine the mechanism of signal transduction of TNF-α-regulated IP3R1 in HMCs.Results The levels of IP3R1 mRNA at 2 h post-TNF-α exposure were significantly enhanced and reached peak at 8 h in HMCs (P ＜ 0.01),then descened at 24 h (P ＜ 0.01).The levels of IP3R1 protein at 4 h post-TNF-α exposure were obviously increased and reached peak at 24 h post-TNF-α exposure (P ＜ 0.01).Compared with the control group,safingol (PKC-α inhibitor) and D609 (PC-PLC inhibitor) each significantly suppressed TNF-α-induced expression of IP3R1 mRNA (3.30 ± 0.81) vs.(1.95 ± 0.130,P ＜ 0.05 ; (2.10 ± 0.49),P ＜ 0.01 andIP3R1 protein (3.09±0.13) vs.(1.86+0.39),P＜0.01; (1.98±0.02),P＜0.01.TNF-αpromoted autophosphorylation,and hence the activation,of PKC-α with maximal phosphorylation that occurred 8 h post-stimulation measured by non-radioactive PKC assay,and the effect was marked attenuated by pretreated with D609 or safingol.Conclusions TNF-α increased the expression of IP3R1 and this was mediated,at least in part,through the PC-PLC/PKC-α signaling pathways in HMCs.
ABSTRACT
Objective To explore the effects of TNF-α on the expression of IP3 R1 mRNA and protein in human mesangial cells (HMCs) and elucidate the role of protein kinase C (PKC) in this signal pathway.Methods Quantitative real-time polymerase chain reaction and immunoblot assay were used to examine the effects of TNF-α on IP3R1 mRNA and protein expression.Depletion PKC,the selective inhibitor of PKCα Safingol and inhibitor of PKCδ Rottlerin,overexpression of dominant negative mutant of PKC to examine the mechanism of signal transduction of TNF-α-regulated IP3 R1 in HMCs.PKCα activation was assayed by Western blot.Results TNF-α increased IP3R1 mRNA and protein expression in HMCs,effects that were blocked by prolonged incubted chronic PMA,Safingol and also by domain negative PKCα construct.TNF-α promoted PKCα activation with maximal PKCα phosphorylation that occurred 8 h post-stimulation.Conclusion TNF-α increased the expression of IP3 R1 and this was mediated through the PKCα activation signaling pathways in HMCs.
ABSTRACT
We previously reported that mice lacking JSAP1 (jsap1-/-) were lethal and the brain of jsap1-/- at E18.5 exhibited multiple types of developmental defects, which included impaired axon projection of the corpus callosum and anterior commissures. In the current study, we examined whether the early telencephalic commissures were formed abnormally from the beginning of initial development or whether they arose normally, but have been progressively lost their maintenance in the absence of JSAP1. The early corpus callosum in the brain of jsap1+/+ at E15.5-E16.5 was found to cross the midline with forming a distinct U-shaped tract, whereas the early axonal tract in jsap1-/- appeared to cross the midline in a diffuse manner, but the lately arriving axons did not cross the midline. In the brain of jsap1-/- at E17.5, the axon terminals of lately arriving collaterals remained within each hemisphere, forming an early Probst's bundle-like shape. The early anterior commissure in the brain of jsap1+/+ at E14.5-E15.5 crossed the midline, whereas the anterior commissure in jsap1-/- developed, but was deviated from their normal path before approaching the midline. The axon tracts of the corpus callosum and anterior commissure in the brain of jsap1-/- at E16.5-E17.5 expressed phosphorylated forms of FAK and JNK, however, their expression levels in the axonal tracts were reduced compared to the respective controls in jsap1+/+. Considering the known scaffolding function of JSAP1 for the FAK and JNK pathways, these results suggest that JSAP1 is required for the pathfinding of the developing telencephalic commissures in the early brains.
Subject(s)
Animals , Female , Mice , Pregnancy , Adaptor Proteins, Signal Transducing/genetics , Brain/embryology , Focal Adhesion Kinase 1/genetics , Immunohistochemistry , In Situ Nick-End Labeling , JNK Mitogen-Activated Protein Kinases/genetics , Mice, Knockout , Nerve Tissue Proteins/genetics , Telencephalon/embryologyABSTRACT
Objective To investigate the role of calcitonin gene-related peptide(CGRP)and IP3 signal pathway in ischemic preconditioning(IPC)in the isolated perfused hearts of rats with type 1 diabetes mellitus. Methods Type 1 diabetes mellitus rat models were established in 80 SD rats,and were randomly divided into 4 week(D-4w)group and 8 week (D-8w)group.These two groups were randomly subdivided into model control(D-Cont)group,type 1 diabetes mellitus ischemia-reperfusion(IR)group,IPC group,CGRP(IPC+CGRP)group and IP3 inhibitor wortmanin(IPC+WMN) group.Another 16 rats were served as normal control(N-Cont)group.In vitro perfusion models of isolated hearts were established by Langendorff methods,and CGRP or wortmanin(WMN)were administered during perfusion.The left ventricle function of isolated heart in each group was monitored by multichannel biosignal analysis system,and coronary artery flow was recorded.The serum CGRP levels were detected by ELISA.The activity of lactate dehydrogenase(LDH)and creatine kinase(CK)in effluent of coronary artery was detected by biochemical method.The size of myocardial infarction was determined by NBT staining,and apoptosis of cadiocytes was detected by TUNEL method. Results Compared with N- Cont group,the CGRP level in serum of rats with type 1 diabetes mellitus decreased with time,the basic left ventricle function decreased,while the activity of LDH and CK in effluent of coronary artery,size of myocardial infarction and cardiomyocyte apoptosis index increased(P<0.05).Compared with N-Cont group,the left ventricle function was significantly lower in IR group,and more severe myocardial damage was observed.IPC improved myocardial damage of D-4w IR group,while had no protection on D-8w IR group.Compared with IPC group,the left ventricle function was significantly improved in IPC+CGRP group.IPC+WMN blocked the myocardial protection of D-4w group from IPC.Conclusion CGRP and IP3 signal pathway are involved in the protection provided by IPC in isolated hearts of rats with type 1 diabetes mellitus.
ABSTRACT
The purpose of the present study was to explore changes in rat colon motility, and determine the roles of calcium and inositol (1,4,5)-triphosphate (IP3) in colon dysmotility induced by multiple organ dysfunction syndrome (MODS) caused by bacteria peritonitis. The number of stools, the contractility of the muscle strips and the length of smooth muscle cells (SMC) in the colon, the concentration of calcium and IP3 in SMC, and serum nitric oxide were measured. Number of stools, fecal weight, IP3 concentration in SMC and serum nitric oxide concentration were 0.77 ± 0.52 pellets, 2.51 ± 0.39 g, 4.14 ± 2.07 pmol/tube, and 113.95 ± 37.89 mumol/L, respectively, for the MODS group (N = 11) vs 1.54 ± 0.64 pellets, 4.32 ± 0.57 g, 8.19 ± 3.11 pmol/tube, and 37.42 ± 19.56 mumol/L for the control group (N = 20; P < 0.05). After treatment with 0.1 mM acetylcholine and 0.1 M potassium chloride, the maximum contraction stress of smooth muscle strips, the length of SMC and the changes of calcium concentration were 593 ± 81 and 458 ± 69 g/cm³, 48.1 ± 11.8 and 69.2 ± 15.7 muM, 250 ± 70 and 167 ± 48 percent, respectively, for the control group vs 321 ± 53 and 284 ± 56 g/cm³, 65.1 ± 18.5 and 87.2 ± 23.7 muM, 127 ± 35 and 112 ± 35 percent for the MODS group (P < 0.05). Thus, colon contractility was decreased in MODS, a result possibly related to reduced calcium concentration and IP3 in SMC.
Subject(s)
Animals , Male , Rats , Calcium/physiology , Colon/physiopathology , Gastrointestinal Motility/physiology , /physiology , Multiple Organ Failure/physiopathology , Myocytes, Smooth Muscle/chemistry , Calcium/analysis , Colon/cytology , Immunohistochemistry , /analysis , Nitric Oxide/blood , Rats, WistarABSTRACT
BACKGROUND AND OBJECTIVES: Elevated intracellular calcium level is known to play important roles in the apoptotic pathway. IP3 receptor (ligand-gated channels that release Ca2+ from intracellular stores) is emerging as a key site for regulation of apoptosis. 2-Aminoethoxydiphenyl borate (2-APB) is one of the reliable IP3 receptor antagonists. We examined the effect of 2-APB on gentamicin ototoxicity in vitro, using the HEI-OC1 cell line. MATERIALS AND METHOD: HEI-OC1 cells were trWWeated with 100micrometer gentamicin. Using a CaspACE assay, we measured the caspases-3 activity in the gentamicin treated hair cells with and without 2-APB pre-incubation. We also observed intra-cellular calcium concentrations in HEI-OC1 cells using a confocal microscopy (calcium green-1 stain). Live cell imaging was performed by using fluorescence video-time lapse system. RESULTS: Cytosolic calcium elevation by gentamicin was remarkably inhibited by 2-APB. Caspases-3 activities of gentamicin treated cells were higher than those of the control. After incubation with 2-APB, caspases-3 activities and cell death of gentamicin treated cells were shown to decrease. CONCLUSION: 2-APB reduces Caspases-3 activity in the gentamicin treated HEI-OC1 cells by inhibition of cytosolic calcium increase.
Subject(s)
Apoptosis , Calcium , Caspase 3 , Cell Death , Cell Line , Cytosol , Fluorescence , Gentamicins , Hair , Inositol 1,4,5-Trisphosphate Receptors , Microscopy, ConfocalABSTRACT
OBJECTIVE: We reported the overcoming effect of Ni2+ on the in vitro 2-cell block of mouse embryos. In this study, we aim to investigate whether Ni2+ should induce intracellular Ca2+ transient in the mouse embryos. MATERIALS AND METHODS: Embryos were collected at post hCG 32hr from the oviduct of the ICR mouse and cultured in M2 medium omitted phenol red. Intracellular Ca2+ was checked by using a confocal laser scanning microscope and fluo-3AM by using various intracellular Ca2+ antagonists. RESULTS: In 1mM Ni2+ treated medium which contained Ca2+(1.71mM), 75.7% of the embryos showed [Ca2+]i transient about 200 sec later. In the Ca2+-free medium, 69.8% of the embryos showed [Ca2+]i transient. In U73122, phospholipaseC(PLC) inhibitor (5uM, 10min) pretreated group, 33.3% of the embryos showed [Ca2+]i transient. Heparine, inositol 1,4,5-triphosphate receptor(IP3R) antagonist preinjected embryos showed no response with 1mM Ni2+. In danthrolene treatment, ryanodine receptor(RyR)-antagonist, 43% embryos showed [Ca2+]i transient but they showed delayed response about 340sec in the presence of Ca2+. CONCLUSIONS: Summing up the above results, Ni2+ seems to induce Ca2+-release from the Ca2+-store even in the Ca2+-free medium. IP3 receptors of the mouse 2-cell embryos might have an essential role for the intracellular Ca2+ increase by Ni2+.
Subject(s)
Animals , Mice , Embryonic Structures , Heparin , Inositol 1,4,5-Trisphosphate , Inositol 1,4,5-Trisphosphate Receptors , Mice, Inbred ICR , Oviducts , Phenolsulfonphthalein , RyanodineABSTRACT
Aim To determine the effect of phospholipase C(PLC) on the rabbit platelet triphosphoryl inositol(IP_3) induced by ADP,and then to explore the mechanism of anti-aggregation to platelet by PLC.Method PRP was made from rabbit blood by removing red cells,and then was parted to eight groups.The first group was treated with PSS.The second was treated with with ADP.The third was treated with ASP and then induced by ADP.Four to eight groups were treated with different dose of PLC respectively and then induced by ADP.IP_3 of rabbit platelet was made by trichloro-acetic acid method,and its content was tested by radioimmunological assay.Result IP_3 of rabbit platelet treated with PSS was 0.29 pmol/10~8 platelet.IP_3 of rabbit platelet treated with ADP was 0.39 pmol/10~8 platelet.IP_3 of rabbit platelet,which were treated with ASP 668 ?mol?L~(-1),5,10,15,20 and 25 U PLC?ml~(-1) respectively and then induced by ADP,were 0.29,0.19,0.08,0.15,0.25,0.04 and 0.18 pmoL/10~8 platelet respectively.IP_3 of ADP group was apparently higher than that of PSS group,but the IP_3 of ASP group and different dose PLC group were significantly lower than ADP group(P
ABSTRACT
BACKGORUND: The physiological activity of osteoblsts is known to be closely related to increased intracellular Ca2+ activity ([Ca2+ ]i) in osteoblasts. The cellular regulation of ([Ca2+ ]i) in osteoblasts is mediated by Ca2+ movements associated with Ca2+ release from intracellular Ca2+ stores, and transmembrane Ca2+ influx via Na Ca2+ exchanger, and Ca2+ ATPase. Reactive oxygen species, such as H2O2, play an important role in the regulation of cellular functions, and act as signaling molecules or as toxins in cells. METHODS: Osteoblasts were isolated from the femurs and tibias of neonatal Sprague-Dawley rats, and cultured for 7 days. The cultured osteoblasts were loaded with a Ca2+ -sensitive fluorescent dye, Fura-2 AM ester, and fluorescence images were monitored using a cooled CCD camera. Ca-spike changes upon ATP application were checked for (1) osteoblasts in Ca2+ -free and 2.5 mM CaCl2 normal Tyrode solution, (2) osteoblasts in which the Ca2+ of the endoplastic reticulumin had been depleted with ryanodine, thapsigargin ord caffein, and (3) osteoblasts pretreated with H2O2, in which the expression of iP3 receptor was checked by Western blotting. RESULTS: ATP increased intracellular free Ca2+ regardless of extracellular Ca2+ concentration. When the intracellular Ca2+ store was depleted, the level of increased Ca2+ activity by ATP was suppressed. H2O2 sustained the Ca2+ increase induced by ATP. The expression of iP3 receptor was enhanced by H2O2. CONCLUSiONS:H2O2 modulates intracellular Ca2+ activity in osteoblasts by increasing Ca2+ release from the intracellular Ca2+ stores.