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1.
Plant Physiol ; 192(2): 927-944, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36946208

RESUMO

Lysosome-related organelles (LROs) are a class of heterogeneous organelles conserved in eukaryotes that primarily play a role in storage and secretion. An important function of LROs is to mediate metal homeostasis. Chlamydomonas reinhardtii is a model organism for studying metal ion metabolism; however, structural and functional analyses of LROs in C. reinhardtii are insufficient. Here, we optimized a method for purifying these organelles from 2 populations of cells: stationary phase or overloaded with iron. The morphology, elemental content, and lysosomal activities differed between the 2 preparations, even though both have phosphorus and metal ion storage functions. LROs in stationary phase cells had multiple non-membrane-bound polyphosphate granules to store phosphorus. Those in iron-overloaded cells were similar to acidocalcisomes (ACs), which have a boundary membrane and contain 1 or 2 large polyphosphate granules to store more phosphorus. We established a method for quantifying the capacity of LROs to sequester individual trace metals. Based on a comparative proteomic analysis of these 2 types of LROs, we present a comprehensive AC proteome and identified 113 putative AC proteins. The methods and protein inventories provide a framework for studying the biogenesis and modification of LROs and the mechanisms by which they participate in regulating metal ion metabolism.


Assuntos
Chlamydomonas , Chlamydomonas/metabolismo , Proteômica , Organelas/metabolismo , Lisossomos/metabolismo , Polifosfatos/metabolismo , Fósforo/metabolismo
2.
Mol Hum Reprod ; 29(9)2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37471586

RESUMO

Circular RNAs (circRNAs), which exert critical functions in the regulation of transcriptional and post-transcriptional gene expression, are found in mammalian cells but their functions in mammalian preimplantation embryo development remain poorly understood. Here, we showed that circKDM5B mediated miRNA-128 (miR-128) to regulate porcine early embryo development. We screened circRNAs potentially expressed in porcine embryos through an integrated analysis of sequencing data from mouse and human embryos, as well as porcine oocytes. An authentic circRNA originating from histone demethylase KDM5B (referred to as circKDM5B) was abundantly expressed in porcine embryos. Functional studies revealed that circKDM5B knockdown not only significantly reduced blastocyst formation but also decreased the number of total cells and trophectoderm (TE) cells. Moreover, the knockdown of circKDM5B resulted in the disturbance of tight junction assembly and impaired paracellular sealing within the TE epithelium. Mechanistically, miR-128 inhibitor injection could rescue the early development of circKDM5B knockdown embryos. Taken together, the findings revealed that circKDM5B functions as a miR-128 sponge, thereby facilitating early embryonic development in pigs through the modulation of gene expression linked to tight junction assembly.


Assuntos
Blastocisto , MicroRNAs , RNA Circular , Animais , Humanos , Camundongos , Blastocisto/metabolismo , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Mamíferos/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Suínos , Histona Desmetilases com o Domínio Jumonji/genética
3.
Mol Psychiatry ; 27(12): 5070-5085, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224261

RESUMO

St. John's wort is an herb, long used in folk medicine for the treatment of mild depression. Its antidepressant constituent, hyperforin, has properties such as chemical instability and induction of drug-drug interactions that preclude its use for individual pharmacotherapies. Here we identify the transient receptor potential canonical 6 channel (TRPC6) as a druggable target to control anxious and depressive behavior and as a requirement for hyperforin antidepressant action. We demonstrate that TRPC6 deficiency in mice not only results in anxious and depressive behavior, but also reduces excitability of hippocampal CA1 pyramidal neurons and dentate gyrus granule cells. Using electrophysiology and targeted mutagenesis, we show that hyperforin activates the channel via a specific binding motif at TRPC6. We performed an analysis of hyperforin action to develop a new antidepressant drug that uses the same TRPC6 target mechanism for its antidepressant action. We synthesized the hyperforin analog Hyp13, which shows similar binding to TRPC6 and recapitulates TRPC6-dependent anxiolytic and antidepressant effects in mice. Hyp13 does not activate pregnan-X-receptor (PXR) and thereby loses the potential to induce drug-drug interactions. This may provide a new approach to develop better treatments for depression, since depression remains one of the most treatment-resistant mental disorders, warranting the development of effective drugs based on naturally occurring compounds.


Assuntos
Antidepressivos , Hypericum , Floroglucinol , Canal de Cátion TRPC6 , Terpenos , Animais , Camundongos , Antidepressivos/isolamento & purificação , Antidepressivos/farmacologia , Hypericum/química , Canal de Cátion TRPC6/agonistas , Canal de Cátion TRPC6/química , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologia , Terpenos/isolamento & purificação , Terpenos/farmacologia
4.
Surg Endosc ; 36(11): 8651-8662, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35705757

RESUMO

BACKGROUND: Intrapapillary capillary loop (IPCL) is an important factor for predicting invasion depth of esophageal squamous cell carcinoma (ESCC). The invasion depth is closely related to the selection of treatment strategy. However, diagnosis of IPCLs is complicated and subject to interobserver variability. This study aimed to develop an artificial intelligence (AI) system to predict IPCLs subtypes of precancerous lesions and superficial ESCC. METHODS: Images of magnifying endoscopy with narrow band imaging from three hospitals were collected retrospectively. IPCLs subtypes were annotated on images by expert endoscopists according to Japanese Endoscopic Society classification. The performance of the AI system was evaluated using internal and external validation datasets (IVD and EVD) and compared with that of the 11 endoscopists. RESULTS: A total of 7094 images from 685 patients were used to train and validate the AI system. The combined accuracy of the AI system for diagnosing IPCLs subtypes in IVD and EVD was 91.3% and 89.8%, respectively. The AI system achieved better performance than endoscopists in predicting IPCLs subtypes and invasion depth. The ability of junior endoscopists to diagnose IPCLs subtypes (combined accuracy: 84.7% vs 78.2%, P < 0.0001) and invasion depth (combined accuracy: 74.4% vs 67.9%, P < 0.0001) were significantly improved with AI system assistance. Although there was no significant differences, the performance of senior endoscopists was slightly elevated. CONCLUSIONS: The proposed AI system could improve the diagnostic ability of endoscopists to predict IPCLs classification of precancerous lesions and superficial ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Doença pelo Vírus Ebola , Lesões Pré-Cancerosas , Humanos , Carcinoma de Células Escamosas do Esôfago/patologia , Neoplasias Esofágicas/diagnóstico por imagem , Esofagoscopia/métodos , Inteligência Artificial , Estudos Retrospectivos , Imagem de Banda Estreita/métodos , Lesões Pré-Cancerosas/diagnóstico por imagem , Microvasos/patologia
5.
Surg Endosc ; 34(4): 1722-1728, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31321537

RESUMO

BACKGROUND: The risk factors of duodenal injury from distal migrated biliary plastic stents remain uncertain. The aim of this study was to determine the risk factors of distal migration and its related duodenal injury in patients who underwent placement of a single biliary plastic stent for biliary strictures. METHODS: We retrospectively reviewed all patients with biliary strictures who underwent endoscopic placement of a single biliary plastic stent from January 2006 to October 2017. RESULTS: Two hundred forty-eight patients with 402 endoscopic retrograde cholangiopancreatography procedures were included. The incidence of distal migration was 6.2%. The frequency of duodenal injury was 2.2% in all cases and 36% in cases with distal migration. Benign biliary strictures (BBS), length of the stent above the proximal end of the stricture (> 2 cm), and duration of stent retention (< 3 months) were independently associated with distal migration (p = 0.018, p = 0.009, and p = 0.016, respectively). Duodenal injury occurred more commonly in cases with larger angle (≥ 30°) between the distal end of the stent and the centerline of the patient's body (p = 0.018) or in cases with stent retention < 3 months (p = 0.031). CONCLUSIONS: The risk factors of distal migration are BBS and the length of the stent above the proximal end of the stricture. The risk factor of duodenal injury due to distal migration is large angle (≥ 30°) between the distal end of the stent and the centerline of the patient's body. Distal migration and related duodenal injury are more likely to present during the early period after biliary stenting.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/instrumentação , Colestase/cirurgia , Duodeno/lesões , Migração de Corpo Estranho/etiologia , Stents/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plásticos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
6.
J Neurochem ; 150(6): 678-690, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31310676

RESUMO

Recent investigations propose the acid sphingomyelinase (ASM)/ceramide system as a novel target for antidepressant action. ASM catalyzes the breakdown of the abundant membrane lipid sphingomyelin to the lipid messenger ceramide. This ASM-induced lipid modification induces a local shift in membrane properties, which influences receptor clustering and downstream signaling. Canonical transient receptor potential channels 6 (TRPC6) are non-selective cation channels located in the cell membrane that play an important role in dendritic growth, synaptic plasticity and cognition in the brain. They can be activated by hyperforin, an ingredient of the herbal remedy St. John's wort for treatment of depression disorders. Because of their role in the context of major depression, we investigated the crosstalk between the ASM/ceramide system and TRPC6 ion channels in a pheochromocytoma cell line 12 neuronal cell model (PC12 rat pheochromocytoma cell line). Ca2+ imaging experiments indicated that hyperforin-induced Ca2+ influx through TRPC6 channels is modulated by ASM activity. While antidepressants, known as functional inhibitors of ASM activity, reduced TRPC6-mediated Ca2+ influx, extracellular application of bacterial sphingomyelinase rebalanced TRPC6 activity in a concentration-related way. This effect was confirmed in whole-cell patch clamp electrophysiology recordings. Lipidomic analyses revealed a decrease in very long chain ceramide/sphingomyelin molar ratio after ASM inhibition, which was connected with changes in the abundance of TRPC6 channels in flotillin-1-positive lipid rafts as visualized by western blotting. Our data provide evidence that the ASM/ceramide system regulates TRPC6 channels likely by controlling their recruitment to specific lipid subdomains and thereby fine-tuning their physical properties.


Assuntos
Neurônios/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Canais de Cátion TRPC/metabolismo , Animais , Ceramidas/metabolismo , Células PC12 , Ratos
7.
Sensors (Basel) ; 19(14)2019 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-31337108

RESUMO

Fault diagnosis is critical to ensuring the safety and reliable operation of rotating machinery systems. Long short-term memory networks (LSTM) have received a great deal of attention in this field. Most of the LSTM-based fault diagnosis methods have too many parameters and calculation, resulting in large memory occupancy and high calculation delay. Thus, this paper proposes a low-delay lightweight recurrent neural network (LLRNN) model for mechanical fault diagnosis, based on a special LSTM cell structure with a forget gate. The input vibration signal is segmented into several shorter sub-signals in order to shorten the length of the time sequence. Then, these sub-signals are sent into the network directly and converted into the final diagnostic results without any manual participation. Compared with some existing methods, our experiments illustrate that the proposed method has less memory space occupancy and lower computational delay while maintaining the same level of accuracy.

8.
Zhongguo Zhong Yao Za Zhi ; 43(5): 1001-1007, 2018 Mar.
Artigo em Zh | MEDLINE | ID: mdl-29676100

RESUMO

Based on the anticancer mechanism of biological alkylating agent, we designed and synthesized two alpha pinene derivatives:(1R,5S)-(6,6-dimethylbicyclo[3,1,1]hept-2-en-2-yl)methyl benzenesulfonate and (1R,5S)-(6,6-dimethylbicyclo[3,1,1]hept-2-en-2-yl)methyl 4-methylbenzenesulfonate, of which structures were confirmed by ¹H-NMR, HPLC and MS date. These two compounds showed a good inhibition of tumor cells' proliferation. Further, the computer siuulation of molecular docking and metabolic kinetics indicated that these two copounds may have stable molecular complexation with protein CDK2, which closely related to the cell cycle.


Assuntos
Antineoplásicos/síntese química , Desenho de Fármacos , Monoterpenos/síntese química , Antineoplásicos/farmacologia , Monoterpenos Bicíclicos , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Simulação de Acoplamento Molecular , Monoterpenos/farmacologia , Relação Estrutura-Atividade
10.
Zhongguo Zhong Yao Za Zhi ; 41(14): 2607-2611, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-28905594

RESUMO

Rheum tanguticum from the same area was divided into 8 types of variation according to the plant morphology, content differences of free anthraquinones, combined anthraquinones, double anthrone were studied. The results showed that the functional components of different variation types were significantly different. The average content of free anthraquinone combined anthraquinone was 2.10-6.71 and 15.43-22.04 mg•g⁻¹, respectively. The average content of sennoside A plus sennoside B was 32.88-42.36 mg•g⁻¹. There were significant differences among the difference of 10 kinds of active components, except for sennoside B and physcion glycoside. Interred with the content and proportion of functional components, type B and type E might be potential special medicinal germplasm for diarrhea attack product, type G and type H might be a potential special medicinal germplasm for clearing heat and detoxifing, type C and type F might be potential special medicinal germplasm for activating blood circulation to dissipate blood stasis, type A and type D might be potential special medicinal germplasm with anastaltic funtion. The conclusion laid the foundation for the directional cultivation of fine varieties of special purpose of rhubarb.


Assuntos
Antraquinonas/análise , Medicamentos de Ervas Chinesas/química , Rheum/química , Compostos Fitoquímicos/análise
15.
Hemoglobin ; 38(1): 70-2, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24200214

RESUMO

This study reports a rare case of ß(41/42,Cap)/ß(A) genotype in a girl with ß-thalassemia (ß-thal) minor. The 13-month-old Chinese proband suffered anemia, diarrhea, stunted growth and emaciation. The routine polymerase chain reaction-reverse dot-blot (PCR-RDB) test result for ß-thal mutations indicated that she was a compound heterozygote for ß(41/42) and ß(Cap). However, the complete blood cell (CBC) test gave the following results: mean corpuscular volume (MCV) 79.8 fL, mean corpuscular hemoglobin (MCH) 19.9 pg, with a Hb A2 value of 5.66%, suggesting that the proband also was ß-thal minor. The proband's father showed typical microcytic hypochromic anemia characteristics with a decreased MCV and MCH (63.1 fL and 20.9 pg, respectively) and an increased level of Hb A2 (5.60%), while the proband's mother had normal levels of MCV, MCH and Hb A2. The PCR-RDB test result showed her father was also a compound heterozygote for the ß(41/42) (HBB: c.126_129delCTTT) and ß(Cap) (HBB: c.-11_-8delAAAC) mutations and her mother was normal. Finally, DNA sequencing identified that the ß(41/42) and ß(Cap) mutations of the proband were inherited from her father and located on one ß-globin gene, suggesting that the proband's genotype is ß(41/42,Cap)/ß(A).


Assuntos
Deleção de Sequência , Globinas beta/genética , Talassemia beta/genética , Sequência de Bases , China , Análise Mutacional de DNA , Feminino , Heterozigoto , Humanos , Lactente , Dados de Sequência Molecular , Fenótipo , Alinhamento de Sequência , Talassemia beta/sangue , Talassemia beta/diagnóstico
16.
Cancer Biol Ther ; 25(1): 2306674, 2024 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-38372700

RESUMO

DIRAS family GTPase 1 (DIRAS1) has been reported as a potential tumor suppressor in other human cancer. However, its expression pattern and role in cervical cancer remain unknown. Knockdown of DIRAS1 significantly promoted the proliferation, growth, migration, and invasion of C33A and SiHa cells cultured in vitro. Overexpression of DIRAS1 significantly inhibited the viability and motility of C33A and SiHa cells. Compared with normal cervical tissues, DIRAS1 mRNA levels were significantly lower in cervical cancer tissues. DIRAS1 protein expression was also significantly reduced in cervical cancer tissues compared with para-cancerous tissues. In addition, DIRAS1 expression level in tumor tissues was significantly negatively correlated with the pathological grades of cervical cancer patients. DNA methylation inhibitor (5-Azacytidine) and histone deacetylation inhibitor (SAHA) resulted in a significant increase in DIRAS1 mRNA levels in C33A and SiHa cells, but did not affect DIRAS1 protein levels. FTO inhibitor (FB23-2) significantly down-regulated intracellular DIRAS1 mRNA levels, but significantly up-regulated DIRAS1 protein levels. Moreover, the down-regulation of METTL3 and METTL14 expression significantly inhibited DIRAS1 protein expression, whereas the down-regulation of FTO and ALKBH5 expression significantly increased DIRAS1 protein expression. In conclusion, DIRAS1 exerts a significant anti-oncogenic function and its expression is significantly downregulated in cervical cancer cells. The m6A modification may be a key mechanism to regulate DIRAS1 mRNA stability and protein translation efficiency in cervical cancer.


Assuntos
Adenina/análogos & derivados , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/genética , Azacitidina/farmacologia , RNA Mensageiro/genética , Metiltransferases , GTP Fosfo-Hidrolases , Proteínas Supressoras de Tumor , Dioxigenase FTO Dependente de alfa-Cetoglutarato
17.
World J Gastroenterol ; 30(9): 1257-1260, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38577178

RESUMO

The increasing popularity of endoscopic submucosal dissection (ESD) as a treatment for early gastric cancer has highlighted the importance of quality assessment in achieving curative resections. This article emphasizes the significance of evaluating ESD quality, not only for curative cases but also for non-curative ones. Postoperative assessment relies on the endoscopic curability (eCura) classification, but management strategies for eCuraC-1 tumour with a positive horizontal margin are unclear. Current research primarily focuses on comparing additional surgical procedures in high-risk patients, while studies specifically targeting eCuraC-1 patients are limited. Exploring management strategies and follow-up outcomes for such cases could provide valuable insights. Furthermore, the application of molecular imaging using near-infrared fluorescent tracers holds promise for precise tumour diagnosis and navigation, potentially impacting the management of early-stage gastric cancer patients. Advancing research in these areas is essential for improving the overall efficacy of endoscopic techniques and refining treatment indications.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Resultado do Tratamento , Estudos Retrospectivos , Mucosa Gástrica/diagnóstico por imagem , Mucosa Gástrica/cirurgia , Mucosa Gástrica/patologia
18.
World J Gastrointest Endosc ; 16(5): 259-272, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38813576

RESUMO

BACKGROUND: Esophageal chromoendoscopy with iodine solution is important for detecting early esophageal cancer. The effect of routine treatment for lesions lightly stained with Lugol's iodine solution is limited, and the addition of natural substances to a regular diet is becoming increasingly common. Vinegar has antitumor effects as reported in previous studies. AIM: To evaluate whether vinegar supplementation could improve the prognosis of patients with lightly stained esophageal lesions. METHODS: This prospective single-centre trial included consecutive patients with lightly stained lesions between June 2020 and April 2022. Patients in the experimental group received increased amounts of vinegar for 6 months. The primary outcome of the study was the clinical therapeutic effect. Complications related to vinegar ingestion and adverse events were also recorded in detail. RESULTS: A total of 166 patients were included in the final analysis. There was no significant difference in the baseline data between the two groups. Intention-to-treat (ITT) analysis demonstrated that the rates at which endoscopic characteristics improved were 33.72% in the experimental group and 20.00% in the conventional group (P = 0.007); and the rates at which biopsy pathology improved were 19.77% and 8.75%, respectively (P = 0.011). Additional vinegar consumption had a statistically protective effect on the rate at which endoscopic characteristics improved [hazard ratio (HR) ITT = 2.183, 95%CI: 1.183-4.028; HRper-protocol (PP) = 2.307, 95%CI: 1.202-4.426] and biopsy pathology improved (HRITT = 2.931, 95%CI: 1.212-7.089; HRPP = 3.320, 95%CI: 1.295-8.507). No statistically significant effect of increased vinegar consumption on preventing high-grade intraepithelial neoplasia or early cancer was observed (HRITT = 0.382, 95%CI: 0.079-1.846; HRPP = 0.382, 95%CI: 0.079-1.846). The subgroup analyses indicated that the overall therapeutic improvement of endoscopic characteristics and biopsy pathology seemed more obvious in older (age > 60) male patients with small lesions (lesion size ≤ 0.5 cm). Three patients in the experimental group reported acid regurgitation and heartburn. No adverse event during gastroscopy were recorded during follow-up. CONCLUSION: A moderately increased ingestion of vinegar could not directly reduce the risk of esophageal cancer in the mucosa dysplasia population, but it improved the endoscopic characteristics and ameliorated the biopsy pathology to a certain extent. Further research is needed to verify the effect of nutritional intervention on precancerous esophageal lesions.

19.
J Eye Mov Res ; 17(1)2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699659

RESUMO

Objectives To find out the prevalence rate of pre-myopia among primary school students in the Mianyang Science City Area, analyze its related risk factors, and thus provide a reference for local authorities to formulate policies on the prevention and control of myopia for primary school students. Methods From September to October 2021, Cluster sampling was adopted by our research group to obtain the vision levels of primary school students employing a diopter test in the Science City Area. In addition, questionnaires were distributed to help us find the risk factors associated with pre-myopia. Through the statistical analysis, we identify the main risk factors for pre-myopia and propose appropriate interventions. Results The prevalence rate of pre-myopia among primary school students in the Science City Area was 45.27% (1020/2253), of which 43.82% were boys and 46.92% were girls, with no statistically significant difference in the prevalence rate of myopia between boys and girls (2 =2.171, P=0.141). The results of the linear trend test showed that the prevalence rate of pre-myopia tends to decrease with increasing age (Z=296.521, P=0.000). Logistic regression analysis demonstrated that the main risk factors for pre-myopia were having at least one parent with myopia, spending less than 2 hours a day outdoors, using the eyes continuously for more than 1 hour, looking at electronic screens for more than 2 hours, and having an improper reading and writing posture. Conclusion The Science City Area has a high prevalence rate of pre-myopia among primary school students. It is proposed that students, schools, families, and local authorities work together to increase the time spent outdoors, reduce digital screens and develop scientific use of eye habits.

20.
J Neurochem ; 127(3): 303-13, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23875811

RESUMO

The non-selective cationic transient receptor canonical 6 (TRPC6) channels are involved in synaptic plasticity changes ranging from dendritic growth, spine morphology changes and increase in excitatory synapses. We previously showed that the TRPC6 activator hyperforin, the active antidepressant component of St. John's wort, induces neuritic outgrowth and spine morphology changes in PC12 cells and hippocampal CA1 neurons. However, the signaling cascade that transmits the hyperforin-induced transient rise in intracellular calcium into neuritic outgrowth is not yet fully understood. Several signaling pathways are involved in calcium transient-mediated changes in synaptic plasticity, ranging from calmodulin-mediated Ras-induced signaling cascades comprising the mitogen-activated protein kinase, PI3K signal transduction pathways as well as Ca(2+) /calmodulin-dependent protein kinase II (CAMKII) and CAMKIV. We show that several mechanisms are involved in TRPC6-mediated synaptic plasticity changes in PC12 cells and primary hippocampal neurons. Influx of calcium via TRPC6 channels activates different pathways including Ras/mitogen-activated protein kinase/extracellular signal-regulated kinases, phosphatidylinositide 3-kinase/protein kinase B, and CAMKIV in both cell types, leading to cAMP-response element binding protein phosphorylation. These findings are interesting not only in terms of the downstream targets of TRPC6 channels but also because of their potential to facilitate further understanding of St. John's wort extract-mediated antidepressant activity. Alterations in synaptic plasticity are considered to play an important role in the pathogenesis of depression. Beside several other proteins, TRPC6 channels regulate synaptic plasticity. This study demonstrates that different pathways including Ras/MEK/ERK, PI3K/Akt, and CAMKIV are involved in the improvement of synaptic plasticity by the TRPC6 activator hyperforin, the antidepressant active constituent of St. John's wort extract.


Assuntos
Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/fisiologia , Genes ras/fisiologia , Hipocampo/fisiologia , Neuritos/fisiologia , Neurônios/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Canais de Cátion TRPC/efeitos dos fármacos , Canais de Cátion TRPC/fisiologia , Animais , Antibacterianos/farmacologia , Western Blotting , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ativação Enzimática/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Hipocampo/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Neuritos/efeitos dos fármacos , Proteína Oncogênica v-akt/fisiologia , Células PC12 , Floroglucinol/análogos & derivados , Floroglucinol/farmacologia , Fosforilação , Cultura Primária de Células , Ratos , Terpenos/farmacologia
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