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1.
J Cell Sci ; 135(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34156466

RESUMO

Store-operated Ca2+ entry is a central component of intracellular Ca2+ signaling pathways. The Ca2+ release-activated channel (CRAC) mediates store-operated Ca2+ entry in many different cell types. The CRAC channel is composed of the plasma membrane (PM)-localized Orai1 channel and endoplasmic reticulum (ER)-localized STIM1 Ca2+ sensor. Upon ER Ca2+ store depletion, Orai1 and STIM1 form complexes at ER-PM junctions, leading to the formation of activated CRAC channels. Although the importance of CRAC channels is well described, the underlying mechanisms that regulate the recruitment of Orai1 to ER-PM junctions are not fully understood. Here, we describe the rapid and transient S-acylation of Orai1. Using biochemical approaches, we show that Orai1 is rapidly S-acylated at cysteine 143 upon ER Ca2+ store depletion. Importantly, S-acylation of cysteine 143 is required for Orai1-mediated Ca2+ entry and recruitment to STIM1 puncta. We conclude that store depletion-induced S-acylation of Orai1 is necessary for recruitment to ER-PM junctions, subsequent binding to STIM1 and channel activation.


Assuntos
Canais de Cálcio , Cálcio , Acilação , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Membrana Celular/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Molécula 1 de Interação Estromal/genética , Molécula 1 de Interação Estromal/metabolismo
2.
J Cell Sci ; 135(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34080635

RESUMO

Despite the recognized significance of reversible protein lipidation (S-acylation) for T cell receptor signal transduction, the enzymatic control of this post-translational modification in T cells remains poorly understood. Here, we demonstrate that DHHC21 (also known as ZDHHC21), a member of the DHHC family of mammalian protein acyltransferases, mediates T cell receptor-induced S-acylation of proximal T cell signaling proteins. Using Zdhhc21dep mice, which express a functionally deficient version of DHHC21, we show that DHHC21 is a Ca2+/calmodulin-dependent enzyme critical for activation of naïve CD4+ T cells in response to T cell receptor stimulation. We find that disruption of the Ca2+/calmodulin-binding domain of DHHC21 does not affect thymic T cell development but prevents differentiation of peripheral CD4+ T cells into Th1, Th2 and Th17 effector T helper lineages. Our findings identify DHHC21 as an essential component of the T cell receptor signaling machinery and define a new role for protein acyltransferases in regulation of T cell-mediated immunity.


Assuntos
Linfócitos T CD4-Positivos , Cálcio , Acetiltransferases , Aciltransferases/genética , Animais , Diferenciação Celular , Camundongos , Receptores de Antígenos de Linfócitos T/genética
3.
Artigo em Chinês | MEDLINE | ID: mdl-34521171

RESUMO

Objective: To explore the influencing factors for serum potassium >4.4 mmol/L in the morning of parathyroidectomy in hemodialysis patients with secondary hyperparathyroidism (SHPT). Methods: The clinical data of 72 patients with SHPT who received regular hemodialysis and underwent parathyroidectomy in Guangdong Provincial People's Hospital from January 2012 to December 2018 were analyzed retrospectively. There were 37 males and 35 females, aged from 25 to 69 years, and the dialysis timespan was from 0.5 to 11 years. The levels of parathyroid hormone, serum potassium and serum calcium before hemodialysis were examined one day before operation, and hemodialysis time and dewatering volume after hemodialysis without heparin were recorded, and also the level of serum potassium in the morning of parathyroidectomy was detected. The occurrences of hyperkalemia during and after operation were studied. The factors related to hyperkalemia in the morning of parathyroidectomy were evaluated by Pearson or Spearman correlation analysis, and the cut-off values of risk factors were calculated by receiver operating characteristic (ROC) curve. Results: Serum potassium >4.4 mmol/L in the morning of parathyroidectomy existed in 23 of 72 patients. Correlation analysis showed that serum potassium one day before operation ((4.93±0.56)mmol/L, r=0.656, P<0.001) and dehydration volume ((2.37±0.75)L, r=0.261, P=0.027) were positively correlated with serum potassium in the morning of parathyroidectomy((4.16±0.54)mmol/L). Serum potassium before hemodialysis one day before operation was a main predictor for serum potassium in the morning of parathyroidectomy (AUC=0.791, P<0.001). The cut-off value of serum potassium before hemodialysis one day before operation was 5.0 mmol/L. Conclusion: Serum potassium before hemodialysis one day before operation in patients with SHPT can predict serum potassium in the morning of parathyroidectomy, offering imformation for the safety of operation.


Assuntos
Hiperpotassemia , Hiperparatireoidismo Secundário , Cálcio , Feminino , Humanos , Hiperpotassemia/etiologia , Hiperparatireoidismo Secundário/complicações , Hiperparatireoidismo Secundário/cirurgia , Masculino , Hormônio Paratireóideo , Paratireoidectomia , Diálise Renal , Estudos Retrospectivos
4.
JNMA J Nepal Med Assoc ; 59(238): 597-600, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34508408

RESUMO

Hereditary vitamin D dependent rickets type II is a rare genetic disorder in children characterized by early onset of rickets and deranged biochemical parameters. Low serum calcium level, high alkaline phosphatase, high parathyroid hormone, and high values of 1,25-dihydroxy vitamin D are characteristic biochemical findings. We are reporting a rare case of Vitamin D Dependent Rickets and subsequent improvement after addition of cinacalcet. This is a case report of a 2.5-year-child with Hereditary Vitamin D Dependent Rickets type II receiving cinacalcet as adjunct to oral calcium and calcitriol. Oral cinacalcet (0.25mg/kg/day) was added to the regimen as an adjunct after treatment failure with high dose of oral calcium and calcitriol. A significant improvement in radiological findings and normal homeostasis of calcium, phosphate and parathyroid hormone was achieved after initiation of cinacalcet.


Assuntos
Raquitismo Hipofosfatêmico Familiar , Cálcio , Raquitismo Hipofosfatêmico Familiar/diagnóstico , Raquitismo Hipofosfatêmico Familiar/tratamento farmacológico , Raquitismo Hipofosfatêmico Familiar/genética , Humanos , Hormônio Paratireóideo , Vitamina D , Vitaminas/uso terapêutico
5.
Blood Adv ; 5(17): 3303-3308, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34468723

RESUMO

In patients with Gárdos channelopathy (p.R352H), an increased concentration of intracellular Ca2+ was previously reported. This is a surprising finding because the Gárdos channel (KCa3.1) is a K+ channel. Here, we confirm the increased intracellular Ca2+ for patients with the KCa3.1 mutation p.S314P. Furthermore, we provide the concept of KCa3.1 activity resulting in a flickering of red blood cell (RBC) membranepotential, which activates the CaV2.1 channel allowing Ca2+ to enter the RBC. Activity of the nonselective cation channel Piezo1 modulates the aforementioned interplay in away that a closed Piezo1 is in favor of the KCa3.1-CaV2.1 interaction. In contrast, Piezo1 openings compromise the membrane potential flickering, thus limiting the activity of CaV2.1. With the compound NS309, we mimic a gain-of-function mutation of KCa3.1. Assessing the RBC Ca2+ response by Fluo-4-based flow cytometry and by measuring the membrane potential using the Macey-Bennekou-Egée method, we provide data that support the concept of the KCa3.1/CaV2.1/Piezo1 interplay as a partial explanation for an increased number of high Ca2+ RBCs. With the pharmacological inhibition of KCa3.1 (TRAM34 and Senicapoc), CaV2.1 (ω-agatoxin TK), and Piezo1 (GsMTx-4), we could project the NS309 behavior of healthy RBCs to the RBCs of Gárdos channelopathy patients.


Assuntos
Canalopatias , Agatoxinas , Cálcio/metabolismo , Eritrócitos/metabolismo , Humanos , Canais Iônicos/genética
6.
Chin J Physiol ; 64(4): 202-209, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34472451

RESUMO

Gamma-linolenic acid (GLA), a natural fatty acid obtained from oils of various vegetables and seeds, has been demonstrated as an anticancer agent. In this work, we investigated the anticancer effects of GLA on breast cancer BT-474 cells. GLA at 30 µM, a concentration reportedly within the range of circulating concentrations in clinical studies, caused apoptotic cell death. GLA caused an elevation in mitochondrial Ca2+ level and a decrease in mitochondrial membrane potential. GLA treatment depleted cyclopiazonic acid (CPA)-sensitive Ca2+ store and triggered substantial Ca2+ influx. Intracellular Ca2+ release triggered by GLA was suppressed by 3 µM xestospongin C (XeC, IP3 receptor-channel blocker) and 100 µM ryanodine (ryanodine receptor-channel blocker), suggesting that the Ca2+ release was via IP3 receptor-channel and ryanodine receptor-channel. Increased expressions of p-eIF2α and CHOP were observed in GLA-treated cells, suggesting GLA-treated cells had increased expressions of p-eIF2α and CHOP, which suggest endoplasmic reticulum (ER) stress. In addition, GLA elicited increased production of reactive oxygen species. Taken together, our results suggest a basal level of GLA induced apoptotic cell death by causing Ca2+ overload, mitochondrial dysfunction, Ca2+ store depletion, ER stress, and oxidative stress. This is the first report to show that GLA caused Ca2+ store depletion and ER stress. GLA-induced Ca2+ store depletion resulted from opening of IP3 receptor-channel and ryanodine receptor-channel.


Assuntos
Neoplasias da Mama , Ácido gama-Linolênico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Feminino , Humanos , Estresse Oxidativo , Ácido gama-Linolênico/metabolismo
8.
Int Braz J Urol ; 47(6): 1136-1147, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34469666

RESUMO

PURPOSE: to evaluate the effect of low-calorie diet on 24-hour urinary metabolic parameters of obese adults with idiopathic calcium oxalate kidney stones. MATERIALS AND METHODS: Adult idiopathic calcium oxalate stone formers, with body mass index (BMI) ≥30kg/m2 and a known lithogenic metabolic abnormality, were submitted to low-calorie diet for twelve weeks. After enrolment, anthropometric measures, serum exams, 24-hour urinary metabolic parameters and body impedance were collected one month prior to dietary intervention and at the end of twelve weeks. Correlations between weight loss, waist circumference loss, fat loss and variation in 24-hour urinary lithogenic parameters and calcium oxalate urinary supersaturation (CaOx SS) as per Tiselius equation were analysed. RESULTS: From January 2017 to January 2018, 39 patients were enrolled to participate in this study. Median (range) prescribed diet was 1300 (1100-2100) Kcal/day. Mean age was 51.7±11.0 (29-68) years old and 69.2% were female. 30.8% of the participants shifted from obesity to BMI < 30kg/m2 and none to BMI < 25kg/m2. A significant correlation was found between baseline 24-hour urinary oxalate and weight (p=0.018) and BMI (p=0.026). No correlation was found between variation of weight, waist circumference, fat mass and 24-h urinary stone risk factors or CaOx SS. CONCLUSIONS: Short-term modest weight loss induced by twelve weeks of low-calorie diet is not associated with a decrease of 24-hour urinary lithogenic parameters in idiopathic calcium oxalate stone formers. Calcium oxalate urinary stone formation is probably multifactorial and driven by other factors than weight.


Assuntos
Cálculos Renais , Cálculos Urinários , Adulto , Idoso , Cálcio , Oxalato de Cálcio , Restrição Calórica , Feminino , Humanos , Cálculos Renais/etiologia , Pessoa de Meia-Idade , Obesidade/complicações
9.
Ann Palliat Med ; 10(8): 9025-9038, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34488389

RESUMO

BACKGROUND: Cisplatin has been a vital drug used for tumor treatment because of its excellent effect on numerous malignant solid cancers. Nonetheless, its nephrotoxicity is non-negligible in clinical practice. This study aims to provide a new understanding of the molecular mechanism of transient receptor potential ankyrin 1 (TRPA1) in cisplatin-induced renal apoptosis. METHODS: We evaluated the effect on apoptosis, TRPA1 expression, and intracellular calcium concentration of human kidney 2 (HK-2) cells induced by diamminedichloroplatinum (DDP). Additionally, we also assessed DDP-induced apoptosis, the expression of Bax, caspase3, cleaved-cas3, p53, Bcl-2 and intracellular calcium concentration combined with HC-030031 and/or pifithrin-α. The effect of FK506 on apoptosis of HK-2 cells induced by DDP and the expression of the nuclear factor of activated T cells (NFAT) protein treated with HC-030031, pifithrin-α, and/or FK506 were also explored. RESULTS: The results showed that apoptosis, TRPA1 expression, and intracellular calcium concentration of HK-2 cell induced by DDP were enhanced in a dose-dependent manner. HC-030031 and pifithrin-α relieved apoptosis, and intracellular calcium concentration and the expression of NFAT and phospho-NFAT (p-NFAT) were induced by DDP. HC-030031 combined with pifithrin-α further aggravated the above-mentioned tendency, including relieved apoptosis, intracellular calcium concentration, and NFAT and p-NFAT expression. HC-030031 and FK506 decelerated the apoptosis, and NFAT and p-NFAT expression of HK-2 cells was induced by DDP, while simultaneous treatment with HC-030031 and FK506 further decreased apoptosis and protein expression. However, the expression of Bcl-2 increased when HC-030031, pifithrin-α, or FK506 was used alone, and HC-030031 combined with pifithrin-α or FK506 further improved the expression of Bcl-2. CONCLUSIONS: TRPA1 mediates cisplatin-induced apoptosis in renal tubular cells via the calcineurin-nuclear factor of activated T-cells-p53 signaling pathway.


Assuntos
Apoptose , Cálcio , Cisplatino , Túbulos Renais/citologia , Transdução de Sinais , Canal de Cátion TRPA1/metabolismo , Linhagem Celular , Cisplatino/farmacologia , Humanos
10.
Ann Palliat Med ; 10(8): 9304-9308, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34488417

RESUMO

Hypercalcemia is a clinical emergency which can cause hypercalcemic crisis and even endanger patients' lives. The increase of serum calcium concentration is caused by the redistribution of calcium in bone and the inhibition of parathyroid secretion, which is known as non-parathyroid hypercalcemia. In this report, we presented a rare case of non-parathyroid hypercalcemia during lactation in order to optimize the diagnosis and treatment of this condition. A 27-year-old female patient was admitted to Wuxi People's Hospital on July 11, 2019 due to "fatigue, anorexia, and pain in both knees for half a month". The patient had fatigue and discomfort, accompanied by pain in both knees without obvious inducement. At the same time, the patient had decreased food intake. In the past 3 days, the symptoms worsened, accompanied by limb numbness. The serum calcium level was increased and the parathyroid hormone (PTH) level was decreased. The patient was diagnosed with hypercalcemia, and was treated with calcitonin and lactation termination. The knee pain disappeared and serum calcium returned to normal during a 2-week follow-up. To conclude, the correlation between hypercalcemia and lactation needs to be considered for non-parathyroid hypercalcemia during lactation. After excluding other possible causes, lactation termination therapy may be an effective therapeutic strategy for non-parathyroid hypercalcemia caused by excessive lactation.


Assuntos
Hipercalcemia , Adulto , Cálcio , Feminino , Humanos , Hipercalcemia/etiologia , Lactação , Dor , Hormônio Paratireóideo
11.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445509

RESUMO

Ischemia-like conditions reflect almost the entire spectrum of events that occur during cerebral ischemia, including the induction of oxidative stress, Ca2+ overload, glutamate excitotoxicity, and activation of necrosis and apoptosis in brain cells. Mechanisms for the protective effects of the antioxidant enzyme peroxiredoxin-6 (Prx-6) on hippocampal cells during oxygen-glucose deprivation/reoxygenation (OGD/R) were investigated. Using the methods of fluorescence microscopy, inhibitory analysis, vitality tests and PCR, it was shown that 24-h incubation of mixed hippocampal cell cultures with Prx-6 does not affect the generation of a reversible phase of a OGD-induced rise in Ca2+ ions in cytosol ([Ca2+]i), but inhibits a global increase in [Ca2+]i in astrocytes completely and in neurons by 70%. In addition, after 40 min of OGD, cell necrosis is suppressed, especially in the astrocyte population. This effect is associated with the complex action of Prx-6 on neuroglial networks. As an antioxidant, Prx-6 has a more pronounced and astrocyte-directed effect, compared to the exogenous antioxidant vitamin E (Vit E). Prx-6 inhibits ROS production in mitochondria by increasing the antioxidant capacity of cells and altering the expression of genes encoding redox status proteins. Due to the close bond between [Ca2+]i and intracellular ROS, this effect of Prx-6 is one of its protective mechanisms. Moreover, Prx-6 effectively suppresses not only necrosis, but also apoptosis during OGD and reoxygenation. Incubation with Prx-6 leads to activation of the basic expression of genes encoding protective kinases-PI3K, CaMKII, PKC, anti-apoptotic proteins-Stat3 and Bcl-2, while inhibiting the expression of signaling kinases and factors involved in apoptosis activation-Ikk, Src, NF-κb, Caspase-3, p53, Fas, etc. This effect on the basic expression of the genome leads to the cell preconditions, which is expressed in the inhibition of caspase-3 during OGD/reoxygenation. A significant effect of Prx-6 is directed on suppression of the level of pro-inflammatory cytokine IL-1ß and factor TNFα, as well as genes encoding NMDA- and kainate receptor subunits, which was established for the first time for this antioxidant enzyme. The protective effect of Prx-6 is due to its antioxidant properties, since mutant Prx-6 (mutPrx-6, Prx6-C47S) leads to polar opposite effects, contributing to oxidative stress, activation of apoptosis and cell death through receptor action on TLR4.


Assuntos
Astrócitos/citologia , Hipocampo/citologia , Peroxirredoxina VI/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Cálcio/metabolismo , Células Cultivadas , Citosol/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Interleucina-1beta/metabolismo , Microscopia de Fluorescência , Peroxirredoxina VI/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
Int J Mol Sci ; 22(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34360637

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by increased activation of fibroblasts/myofibroblasts. Previous reports have shown that IPF fibroblasts are resistant to apoptosis, but the mechanisms remain unclear. Since inhibition of the mitochondrial permeability transition pore (mPTP) has been implicated in the resistance to apoptosis, in this study, we analyzed the role of mitochondrial function and the mPTP on the apoptosis resistance of IPF fibroblasts under basal conditions and after mitomycin C-induced apoptosis. We measured the release of cytochrome c, mPTP opening, mitochondrial calcium release, oxygen consumption, mitochondrial membrane potential, ADP/ATP ratio, ATP concentration, and mitochondrial morphology. We found that IPF fibroblasts were resistant to mitomycin C-induced apoptosis and that calcium, a well-established activator of mPTP, is decreased as well as the release of pro-apoptotic proteins such as cytochrome c. Likewise, IPF fibroblasts showed decreased mitochondrial function, while mPTP was less sensitive to ionomycin-induced opening. Although IPF fibroblasts did not present changes in the mitochondrial membrane potential, we found a fragmented mitochondrial network with scarce, thinned, and disordered mitochondria with reduced ATP levels. Our findings demonstrate that IPF fibroblasts are resistant to mitomycin C-induced apoptosis and that altered mPTP opening contributes to this resistance. In addition, IPF fibroblasts show mitochondrial dysfunction evidenced by a decrease in respiratory parameters.


Assuntos
Apoptose , Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Mitocôndrias/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Citocromos c/metabolismo , Fibroblastos/patologia , Humanos , Fibrose Pulmonar Idiopática/etiologia , Fibrose Pulmonar Idiopática/patologia , Ionomicina , Mitocôndrias/patologia , Mitomicina , Oxigênio/metabolismo , Cultura Primária de Células
13.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445119

RESUMO

The sinoatrial (SA) node is the physiological pacemaker of the heart, and resting heart rate in humans is a well-known risk factor for cardiovascular disease and mortality. Consequently, the mechanisms of initiating and regulating the normal spontaneous SA node beating rate are of vital importance. Spontaneous firing of the SA node is generated within sinoatrial nodal cells (SANC), which is regulated by the coupled-clock pacemaker system. Normal spontaneous beating of SANC is driven by a high level of cAMP-mediated PKA-dependent protein phosphorylation, which rely on the balance between high basal cAMP production by adenylyl cyclases and high basal cAMP degradation by cyclic nucleotide phosphodiesterases (PDEs). This diverse class of enzymes includes 11 families and PDE3 and PDE4 families dominate in both the SA node and cardiac myocardium, degrading cAMP and, consequently, regulating basal cardiac pacemaker function and excitation-contraction coupling. In this review, we will demonstrate similarities between expression, distribution, and colocalization of various PDE subtypes in SANC and cardiac myocytes of different species, including humans, focusing on PDE3 and PDE4. Here, we will describe specific targets of the coupled-clock pacemaker system modulated by dual PDE3 + PDE4 activation and provide evidence that concurrent activation of PDE3 + PDE4, operating in a synergistic manner, regulates the basal cardiac pacemaker function and provides control over normal spontaneous beating of SANCs through (PDE3 + PDE4)-dependent modulation of local subsarcolemmal Ca2+ releases (LCRs).


Assuntos
Relógios Biológicos/fisiologia , Miócitos Cardíacos/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Nó Sinoatrial/metabolismo , Animais , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , AMP Cíclico/metabolismo , Humanos
14.
Int J Mol Sci ; 22(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34445774

RESUMO

Polyethyleneimine (PEI) induced immune responses were investigated in human bronchial epithelial (hBE) cells and mice. PEI rapidly induced ATP release from hBE cells and pretreatment with glutathione (GSH) blocked the response. PEI activated two conductive pathways, VDAC-1 and pannexin 1, which completely accounted for ATP efflux across the plasma membrane. Moreover, PEI increased intracellular Ca2+ concentration ([Ca2+]i), which was reduced by the pannexin 1 inhibitor, 10Panx (50 µM), the VDAC-1 inhibitor, DIDS (100 µM), and was nearly abolished by pretreatment with GSH (5 mM). The increase in [Ca2+]i involved Ca2+ uptake through two pathways, one blocked by oxidized ATP (oATP, 300 µM) and another that was blocked by the TRPV-1 antagonist A784168 (100 nM). PEI stimulation also increased IL-33 mRNA expression and protein secretion. In vivo experiments showed that acute (4.5 h) PEI exposure stimulated secretion of Th2 cytokines (IL-5 and IL-13) into bronchoalveolar lavage (BAL) fluid. Conjugation of PEI with ovalbumin also induced eosinophil recruitment and secretion of IL-5 and IL-13 into BAL fluid, which was inhibited in IL-33 receptor (ST2) deficient mice. In conclusion, PEI-induced oxidative stress stimulated type 2 immune responses by activating ATP-dependent Ca2+ uptake leading to IL-33 secretion, similar to allergens derived from Alternaria.


Assuntos
Trifosfato de Adenosina/imunologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Imunidade/efeitos dos fármacos , Nanopartículas/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Polietilenoimina/farmacologia , Alérgenos/imunologia , Animais , Cálcio/imunologia , Células Cultivadas , Citocinas/imunologia , Feminino , Humanos , Imunidade/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/imunologia , RNA Mensageiro/imunologia , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/imunologia
15.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445270

RESUMO

The opening of the permeability transition pore (mPTP) in mitochondria initiates cell death in numerous diseases. The regulation of mPTP by NAD(H) in the mitochondrial matrix is well established; however, the role of extramitochondrial (cytosolic) NAD(H) is still unclear. We studied the effect of added NADH and NAD+ on: (1) the Ca2+-retention capacity (CRC) of isolated rat liver, heart, and brain mitochondria; (2) the Ca2+-dependent mitochondrial swelling in media whose particles can (KCl) or cannot (sucrose) be extruded from the matrix by mitochondrial carriers; (3) the Ca2+-dependent mitochondrial depolarization and the release of entrapped calcein from mitochondria of permeabilized hepatocytes; and (4) the Ca2+-dependent mitochondrial depolarization and subsequent repolarization. NADH and NAD+ increased the CRC of liver, heart, and brain mitochondria 1.5-2.5 times, insignificantly affecting the rate of Ca2+-uptake and the free Ca2+ concentration in the medium. NAD(H) suppressed the Ca2+-dependent mitochondrial swelling both in KCl- and sucrose-based media but did not induce the contraction and repolarization of swollen mitochondria. By contrast, EGTA caused mitochondrial repolarization in both media and the contraction in KCl-based medium only. NAD(H) delayed the Ca2+-dependent depolarization and the release of calcein from individual mitochondria in hepatocytes. These data unambiguously demonstrate the existence of an external NAD(H)-dependent site of mPTP regulation.


Assuntos
Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Hepáticas/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , NAD/metabolismo , Animais , Cálcio/metabolismo , Fluoresceínas/metabolismo , Hepatócitos/metabolismo , Masculino , Ratos , Ratos Wistar
16.
Int J Mol Sci ; 22(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34445344

RESUMO

Thyroid hormones, including 3,5,3'-triiodothyronine (T3), cause a wide spectrum of genomic effects on cellular metabolism and bioenergetic regulation in various tissues. The non-genomic actions of T3 have been reported but are not yet completely understood. Acute T3 treatment significantly enhanced basal, maximal, ATP-linked, and proton-leak oxygen consumption rates (OCRs) of primary differentiated mouse brown adipocytes accompanied with increased protein abundances of uncoupling protein 1 (UCP1) and mitochondrial Ca2+ uniporter (MCU). T3 treatment depolarized the resting mitochondrial membrane potential (Ψm) but augmented oligomycin-induced hyperpolarization in brown adipocytes. Protein kinase B (AKT) and mammalian target of rapamycin (mTOR) were activated by T3, leading to the inhibition of autophagic degradation. Rapamycin, as an mTOR inhibitor, blocked T3-induced autophagic suppression and UCP1 upregulation. T3 increases intracellular Ca2+ concentration ([Ca2+]i) in brown adipocytes. Most of the T3 effects, including mTOR activation, UCP1 upregulation, and OCR increase, were abrogated by intracellular Ca2+ chelation with BAPTA-AM. Calmodulin inhibition with W7 or knockdown of MCU dampened T3-induced mitochondrial activation. Furthermore, edelfosine, a phospholipase C (PLC) inhibitor, prevented T3 from acting on [Ca2+]i, UCP1 abundance, Ψm, and OCR. We suggest that short-term exposure of T3 induces UCP1 upregulation and mitochondrial activation due to PLC-mediated [Ca2+]i elevation in brown adipocytes.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Cálcio/metabolismo , Mitocôndrias/efeitos dos fármacos , Tri-Iodotironina/farmacologia , Tecido Adiposo Marrom/metabolismo , Animais , Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Células Cultivadas , Metabolismo Energético/efeitos dos fármacos , Feminino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos
17.
Int J Mol Sci ; 22(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34445792

RESUMO

Otolin-1 is a scaffold protein of otoliths and otoconia, calcium carbonate biominerals from the inner ear. It contains a gC1q domain responsible for trimerization and binding of Ca2+. Knowledge of a structure-function relationship of gC1q domain of otolin-1 is crucial for understanding the biology of balance sensing. Here, we show how natural variants alter the structure of gC1q otolin-1 and how Ca2+ are able to revert some effects of the mutations. We discovered that natural substitutions: R339S, R342W and R402P negatively affect the stability of apo-gC1q otolin-1, and that Q426R has a stabilizing effect. In the presence of Ca2+, R342W and Q426R were stabilized at higher Ca2+ concentrations than the wild-type form, and R402P was completely insensitive to Ca2+. The mutations affected the self-association of gC1q otolin-1 by inducing detrimental aggregation (R342W) or disabling the trimerization (R402P) of the protein. Our results indicate that the natural variants of gC1q otolin-1 may have a potential to cause pathological changes in otoconia and otoconial membrane, which could affect sensing of balance and increase the probability of occurrence of benign paroxysmal positional vertigo (BPPV).


Assuntos
Proteínas da Matriz Extracelular/genética , Mutação/genética , Domínios Proteicos/genética , Sequência de Aminoácidos , Vertigem Posicional Paroxística Benigna/genética , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Humanos
18.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445394

RESUMO

Cytotoxic effects of cannabidiol (CBD) and tamoxifen (TAM) have been observed in several cancer types. We have recently shown that CBD primarily targets mitochondria, inducing a stable mitochondrial permeability transition pore (mPTP) and, consequently, the death of acute lymphoblastic leukemia (T-ALL) cells. Mitochondria have also been documented among cellular targets for the TAM action. In the present study we have demonstrated a synergistic cytotoxic effect of TAM and CBD against T-ALL cells. By measuring the mitochondrial membrane potential (ΔΨm), mitochondrial calcium ([Ca2+]m) and protein-ligand docking analysis we determined that TAM targets cyclophilin D (CypD) to inhibit mPTP formation. This results in a sustained [Ca2+]m overload upon the consequent CBD administration. Thus, TAM acting on CypD sensitizes T-ALL to mitocans such as CBD by altering the mitochondrial Ca2+ homeostasis.


Assuntos
Cálcio/metabolismo , Canabidiol/farmacologia , Ciclofilina D/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Tamoxifeno/farmacologia , Linhagem Celular Tumoral , Ciclofilina D/química , Sinergismo Farmacológico , Homeostase/efeitos dos fármacos , Humanos , Células Jurkat , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Modelos Moleculares , Simulação de Acoplamento Molecular , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Conformação Proteica
19.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360934

RESUMO

The activity of specific populations of neurons in different brain areas makes decisions regarding proper synaptic transmission, the ability to make adaptations in response to different external signals, as well as the triggering of specific regulatory pathways to sustain neural function. The endocannabinoid system (ECS) appears to be a very important, highly expressed, and active system of control in the central nervous system (CNS). Functionally, it allows the cells to respond quickly to processes that occur during synaptic transmission, but can also induce long-term changes. The endocannabinoids (eCBs) belong to a large family of bioactive lipid mediators that includes amides, esters, and ethers of long-chain polyunsaturated fatty acids. They are produced "on demand" from the precursors located in the membranes, exhibit a short half-life, and play a key role as retrograde messengers. eCBs act mainly through two receptors, CB1R and CB2R, which belong to the G-protein coupled receptor superfamily (GPCRs), but can also exert their action via multiple non-receptor pathways. The action of eCBs depends on Ca2+, but eCBs can also regulate downstream Ca2+ signaling. In this short review, we focus on the regulation of neuronal calcium channels by the most effective members of eCBs-2-arachidonoylglycerol (2-AG), anandamide (AEA) and originating from AEA-N-arachidonoylglycine (NAGly), to better understand the contribution of ECS to brain function under physiological conditions.


Assuntos
Encéfalo/metabolismo , Canais de Cálcio/metabolismo , Cálcio/metabolismo , Endocanabinoides/metabolismo , Transmissão Sináptica , Animais , Humanos , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Transdução de Sinais
20.
Nutrients ; 13(8)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34444650

RESUMO

This systematic review assessed genotypes and changes in calcium homeostasis. A literature search was performed in EMBASE, Medline and CENTRAL on 7 August 2020 identifying 1012 references. Studies were included with any human population related to the topic of interest, and genetic variations in genes related to calcium metabolism were considered. Two reviewers independently screened references, extracted relevant data and assessed study quality using the Q-Genie tool. Forty-one studies investigating Single Nucleotide Polymorphisms (SNPs) in relation to calcium status were identified. Almost half of the included studies were of good study quality according to the Q-Genie tool. Seventeen studies were cross-sectional, 14 case-control, seven association and three were Mendelian randomization studies. Included studies were conducted in over 18 countries. Participants were mainly adults, while six studies included children and adolescents. Ethnicity was described in 31 studies and half of these included Caucasian participants. Twenty-six independent studies examined the association between calcium and polymorphism in the calcium-sensing receptor (CASR) gene. Five studies assessed the association between polymorphisms of the Vitamin D receptor (VDR) gene and changes in calcium levels or renal excretion. The remaining ten studies investigated calcium homeostasis and other gene polymorphisms such as the CYP24A1 SNP or CLDN14. This study identified several CASR, VDR and other gene SNPs associated with calcium status. However, to provide evidence to guide dietary recommendations, further research is needed to explore the association between common polymorphisms and calcium requirements.


Assuntos
Cálcio/metabolismo , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Receptores de Detecção de Cálcio/genética , Cálcio na Dieta/administração & dosagem , Suplementos Nutricionais , Feminino , Genótipo , Homeostase , Humanos , Masculino
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