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1.
Nature ; 629(8014): 1118-1125, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38778102

RESUMO

Higher plants survive terrestrial water deficiency and fluctuation by arresting cellular activities (dehydration) and resuscitating processes (rehydration). However, how plants monitor water availability during rehydration is unknown. Although increases in hypo-osmolarity-induced cytosolic Ca2+ concentration (HOSCA) have long been postulated to be the mechanism for sensing hypo-osmolarity in rehydration1,2, the molecular basis remains unknown. Because osmolarity triggers membrane tension and the osmosensing specificity of osmosensing channels can only be determined in vivo3-5, these channels have been classified as a subtype of mechanosensors. Here we identify bona fide cell surface hypo-osmosensors in Arabidopsis and find that pollen Ca2+ spiking is controlled directly by water through these hypo-osmosensors-that is, Ca2+ spiking is the second messenger for water status. We developed a functional expression screen in Escherichia coli for hypo-osmosensitive channels and identified OSCA2.1, a member of the hyperosmolarity-gated calcium-permeable channel (OSCA) family of proteins6. We screened single and high-order OSCA mutants, and observed that the osca2.1/osca2.2 double-knockout mutant was impaired in pollen germination and HOSCA. OSCA2.1 and OSCA2.2 function as hypo-osmosensitive Ca2+-permeable channels in planta and in HEK293 cells. Decreasing osmolarity of the medium enhanced pollen Ca2+ oscillations, which were mediated by OSCA2.1 and OSCA2.2 and required for germination. OSCA2.1 and OSCA2.2 convert extracellular water status into Ca2+ spiking in pollen and may serve as essential hypo-osmosensors for tracking rehydration in plants.


Assuntos
Arabidopsis , Sinalização do Cálcio , Cálcio , Germinação , Concentração Osmolar , Pólen , Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Germinação/genética , Mutação , Pólen/genética , Pólen/metabolismo , Água/metabolismo , Células HEK293 , Humanos , Desidratação
2.
J Pharm Pharmacol ; 75(12): 1530-1543, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-37774413

RESUMO

OBJECTIVES: The activation of store-operated calcium entry (SOCE) channel and endoplasmic reticulum stress (ERS) induced by high glucose (HG) is recognized as a major cause of vascular endothelial dysfunction. This study aims to investigate the protective effect of homoplantaginin (Hom) on HG-induced endothelial dysfunction. METHODS: HG-induced vascular endothelial dysfunction model in human umbilical vein endothelial cells (HUVECs) and rat-isolated thoracic aortas were established to observe the protective effect of Hom, further evaluated the mechanism of SOCE channel and ERS in the pathogenesis. KEY FINDINGS: Hom increased the levels of nitric oxide (NO) and phospho-endothelial nitric oxide synthase (p-eNOS) in HUVECs and isolated rat thoracic aortas in a dose-dependent manner, restored acetylcholine-mediated endothelium-dependent vasodilation. Network pharmacology showed that the pathogenesis of diabetic vascular complications may involve calcium (Ca2+) signal pathway. Hom reduced Ca2+ concentration via blocking SOCE channel in HUVECs, and resisted ERS activation by down-regulating ERS-related proteins expression. Importantly, SKF96365 (SOCE inhibitor) intervention experiment showed that Hom inhibited ERS activation by blocking the SOCE channel, further increased the levels of NO and p-eNOS. CONCLUSION: Hom could alleviate HG-induced vascular endothelial dysfunction by inhibiting SOCE channel and ERS. This provided a potential pharmacological intervention strategy for the treatment of vascular endothelial dysfunction.


Assuntos
Cálcio , Glucose , Humanos , Ratos , Animais , Cálcio/metabolismo , Células Endoteliais da Veia Umbilical Humana , Glucose/farmacologia , Estresse do Retículo Endoplasmático
3.
J Plant Physiol ; 287: 154045, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37356321

RESUMO

Plant cell walls are embedded in a pectin matrix which is physically linked with the wall-associated kinases (WAKs), a subfamily of receptor-like kinases that participate in the cell wall integrity (CWI) sensing. Since cell walls are also the main binding sites for boron (B) and aluminum (Al), WAK may be potentially associated with the regulation of plant responses to Al toxicity and B deficiency. Using pea as a model species, we have identified a total of 28 WAK genes in the genome and named them according to its chromosomal location. All the PsWAKs were phylogenetically grouped into three clades. Phylogenetic relationship and synteny analysis showed that the PsWAKs in pea and Glycine max or Medicago truncatula shared a relatively conserved evolutionary history. Protein domain, motif, and transmembrane analysis indicated that all PsWAK proteins were predicted to be localized to the plasma membrane, and most PsWAKs shared a similar structure to their homologs. The RNA-seq data showed that the expression pattern of WAK genes in response to B deficiency was similar to that of Al toxicity, with most of PsWAKs being up-regulated. The qRT-PCR results further confirmed that PsWAK5, PsWAK9 and PsWAK14 were more specific for both B-deficiency and Al toxicity, and the expression levels of PsWAK5, PsWAK9 and PsWAK14 were significantly higher in the Al-sensitive cultivar Hyogo than in the Al-resistant cultivar Alaska under Al toxicity. This study provided an important basis for the functional and evolutionary analysis of PsWAKs and linked them to responses to cell wall damage induced by B-deficiency and Al toxicity, suggesting that PsWAKs may play a key role in the perception of cell wall integrity under Al toxicity or B-deficiency, as well as in the regulation of Al tolerance in pea.


Assuntos
Alumínio , Pisum sativum , Pisum sativum/genética , Pisum sativum/metabolismo , Alumínio/toxicidade , Alumínio/metabolismo , Filogenia , Proteínas Quinases/metabolismo , Parede Celular/genética , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas
4.
Plant Physiol Biochem ; 196: 1122-1136, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36907700

RESUMO

Pinus massoniana is an important industrial crop tree species commonly used for timber and wood pulp for papermaking, rosin, and turpentine. This study investigated the effects of exogenous calcium (Ca) on P. massoniana seedling growth, development, and various biological processes and revealed the underlying molecular mechanisms. The results showed that Ca deficiency led to severe inhibition of seedling growth and development, whereas adequate exogenous Ca markedly improved growth and development. Many physiological processes were regulated by exogenous Ca. The underlying mechanisms involved diverse Ca-influenced biological processes and metabolic pathways. Calcium deficiency inhibited or impaired these pathways and processes, whereas sufficient exogenous Ca improved and benefited these cellular events by regulating several related enzymes and proteins. High levels of exogenous Ca facilitated photosynthesis and material metabolism. Adequate exogenous Ca supply relieved oxidative stress that occurred at low Ca levels. Enhanced cell wall formation, consolidation, and cell division also played a role in exogenous Ca-improved P. massoniana seedling growth and development. Calcium ion homeostasis and Ca signal transduction-related gene expression were also activated at high exogenous Ca levels. Our study facilitates the elucidation of the potential regulatory role of Ca in P. massoniana physiology and biology and is of guiding significance in Pinaceae plant forestry.


Assuntos
Fenômenos Biológicos , Pinus , Cálcio/metabolismo , Pinus/genética , Pinus/metabolismo , Proteômica/métodos , Plântula/metabolismo , Crescimento e Desenvolvimento
5.
Phytother Res ; 37(7): 3025-3041, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36879478

RESUMO

Vascular endothelial cell (VEC) injury is a key factor in the development of diabetic vascular complications. Homoplantaginin (Hom), one of the main flavonoids from Salvia plebeia R. Br. has been reported to protect VEC. However, its effects and mechanisms against diabetic vascular endothelium remain unclear. Here, the effect of Hom on VEC was assessed using high glucose (HG)-treated human umbilical vein endothelial cells and db/db mice. In vitro, Hom significantly inhibited apoptosis and promoted autophagosome formation and lysosomal function such as lysosomal membrane permeability and the expression of LAMP1 and cathepsin B. The antiapoptosis effect of Hom was reversed by autophagy inhibitor chloroquine phosphate or bafilomycin A1. Furthermore, Hom promoted gene expression and nuclear translocation of transcription factor EB (TFEB). TFEB gene knockdown attenuated the effect of Hom on upregulating lysosomal function and autophagy. Moreover, Hom activated adenosine monophosphate-dependent protein kinase (AMPK) and inhibited the phosphorylation of mTOR, p70S6K, and TFEB. These effects were attenuated by AMPK inhibitor Compound C. Molecular docking showed a good interaction between Hom and AMPK protein. Animal studies indicated that Hom effectively upregulated the protein expression of p-AMPK and TFEB, enhanced autophagy, reduced apoptosis, and alleviated vascular injury. These findings revealed that Hom ameliorated HG-mediated VEC apoptosis by enhancing autophagy via the AMPK/mTORC1/TFEB pathway.


Assuntos
Proteínas Quinases Ativadas por AMP , Autofagia , Camundongos , Animais , Humanos , Proteínas Quinases Ativadas por AMP/metabolismo , Simulação de Acoplamento Molecular , Flavonoides/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Glucose/efeitos adversos , Apoptose , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/farmacologia
6.
Plant J ; 114(1): 176-192, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36721978

RESUMO

The supply of boron (B) alleviates the toxic effects of aluminum (Al) on root growth; however, the mechanistic basis of this process remains elusive. This study filled this knowledge gap, demonstrating that boron modifies auxin distribution and transport in Al-exposed Arabidopsis roots. In B-deprived roots, treatment with Al induced an increase in auxin content in the root apical meristem zone (MZ) and transition zone (TZ), whereas in the elongation zone (EZ) the auxin content was decreased beyond the level required for adequate growth. These distribution patterns are explained by the fact that basipetal auxin transport from the TZ to the EZ was disrupted by Al-inhibited PIN-FORMED 2 (PIN2) endocytosis. Experiments involving the modulation of protein biosynthesis by cycloheximide (CHX) and transcriptional regulation by cordycepin (COR) demonstrated that the Al-induced increase of PIN2 membrane proteins was dependent upon the inhibition of PIN2 endocytosis, rather than on the transcriptional regulation of the PIN2 gene. Experiments reporting on the profiling of Al3+ and PIN2 proteins revealed that the inhibition of endocytosis of PIN2 proteins was the result of Al-induced limitation of the fluidity of the plasma membrane. The supply of B mediated the turnover of PIN2 endosomes conjugated with indole-3-acetic acid (IAA), and thus restored the Al-induced inhibition of IAA transport through the TZ to the EZ. Overall, the reported results demonstrate that boron supply mediates PIN2 endosome-based auxin transport to alleviate Al toxicity in plant roots.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Alumínio/toxicidade , Alumínio/metabolismo , Boro/metabolismo , Proteína 1 de Ligação a Repetições Teloméricas/metabolismo , Raízes de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Arabidopsis/metabolismo
7.
Food Funct ; 13(4): 1890-1905, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35084418

RESUMO

Vascular endothelial cell injury induced by high glucose (HG) plays an important role in the occurrence and development of diabetic vascular complications. Yellow tea has a protective effect on vascular endothelial cells. However, the molecular mechanisms underlying this effect are unclear. In this study, the effects of the n-butanol fraction of Huoshan large-leaf yellow tea extract (HLYTBE) on vascular endothelial injury were investigated using human umbilical vein endothelial cells (HUVECs) and diabetic mice. In HUVECs, HLYTBE significantly reduced the production of reactive oxygen species, increased the activity of anti-oxidases (superoxide dismutase and glutathione peroxidase), enhanced the production of reduced glutathione, and decreased the level of oxidized glutathione, thereby improving cell viability. HLYTBE also promoted autophagosome formation, increased the LC3-II/LC3-I ratio, increased the expressions of Beclin1 and Atg 5, and decreased the expression of p62. HLYTBE up-regulated p-AMPK and down regulated p-mTOR, and these effects were reversed by compound C, an AMPK inhibitor. HLYTBE reduced apoptosis and cytochrome C expression, and these effects were attenuated by the autophagy inhibitor 3-methyladenine. In vivo studies showed that HLYTBE improved the impaired pyruvate tolerance, glucose tolerance, and insulin resistance; reduced the concentrations of blood glucose, glycated serum protein, lipids, and 8-isomeric prostaglandin 2α; increased the anti-oxidase activity in serum; and alleviated pathological damage in the thoracic aorta of diabetic mice induced by high sucrose-high fat diet along with streptozotocin. The results suggest that HLYTBE protects the vascular endothelium by up-regulating autophagy via the AMPK/mTOR pathway and inhibiting oxidative stress.


Assuntos
Autofagia/efeitos dos fármacos , Endotélio Vascular , Glucose/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Chá , Animais , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Camundongos , Preparações de Plantas/química , Preparações de Plantas/farmacologia , Regulação para Cima/efeitos dos fármacos
8.
Phytother Res ; 36(1): 433-447, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34859513

RESUMO

Nonalcoholic fatty liver disease is the most prevalent liver disease characterized by excessive lipid accumulation in hepatocytes. Endoplasmic reticulum (ER) stress and autophagy play an important role in lipid accumulation. In this study, scutellarin (Scu) was examined in palmitic acid-treated HepG2 cells and C57/BL6 mice fed a high-fat diet (HFD). Scu reduced intracellular lipid content and inhibited sterol regulatory element binding protein-1c (SREBP-1c)-mediated lipid synthesis and fatty acid translocase-mediated lipid uptake in HepG2 cells. Additionally, Scu restored impaired autophagy and inhibited excessive activation of ER stress in vivo and in vitro. Moreover, Scu upregulated forkhead box O transcription factor 1-mediated autophagy by inhibiting inositol-requiring enzyme 1α (IRE1α)/X-box-binding protein 1 (XBP1) branch activation, while XBP1s overexpression exacerbated the lipid accumulation and impaired autophagy in HepG2 cells and also weakened the positive effects of Scu. Furthermore, Scu attenuated ER stress by activating autophagy, ultimately downregulating SREBP-1c-mediated lipid synthesis, and autophagy inhibitors offset these beneficial effects. Scu inhibited the crosstalk between autophagy and ER stress and downregulated saturated fatty acid-induced lipid accumulation in hepatocytes. These findings demonstrate that Scu ameliorates hepatic lipid accumulation by enhancing autophagy and suppressing ER stress via the IRE1α/XBP1 pathway.


Assuntos
Endorribonucleases , Hepatopatia Gordurosa não Alcoólica , Animais , Apigenina , Autofagia , Ácidos Graxos , Glucuronatos , Inositol , Metabolismo dos Lipídeos , Camundongos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Proteínas Serina-Treonina Quinases , Proteína 1 de Ligação a X-Box/genética
9.
J Exp Bot ; 73(3): 631-635, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34661650

RESUMO

Programmed cell death is a tightly regulated genetically controlled process that leads to cell suicide and eliminates cells that are either no longer needed or damaged/harmful. Nucleotide-binding leucine-rich repeat proteins have recently emerged as a novel class of Ca2+-permeable channels that operate in plant immune responses. This viewpoint argues that the unique structure of this channel, its permeability to other cations, and specificity of its operation make it an ideal candidate to mediate cell signaling and adaptive responses not only to pathogens but also to a broad range of abiotic stress factors.


Assuntos
Proteínas de Repetições Ricas em Leucina , Plantas , Adaptação Fisiológica , Nucleotídeos/metabolismo , Imunidade Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/genética , Plantas/metabolismo , Transdução de Sinais
10.
Artigo em Inglês | MEDLINE | ID: mdl-34594392

RESUMO

OBJECTIVE: To analyze the influence of Bushen Tiaochong cycle therapy on Th1/Th2 deviation, sex hormone level, and pregnancy outcome of alloimmune recurrent spontaneous abortion (RSA). METHODS: From August 2018 to April 2020, 130 patients with alloimmune RSA who met the inclusion criteria were randomly divided into the control group (n = 65) and the study group (n = 65). The former received lymphocyte immunotherapy (LIT), and the latter received Bushen Tiaochong cycle therapy on the basis of LIT. The treatment ended at 12 w of pregnancy. The total score of traditional Chinese medicine (TCM) syndromes, Th1 cytokine (IL-2), Th2 cytokine (IL-10), and related hormones (chorionic gonadotropin (hCG) and progesterone (P)) were compared between the two groups before and after treatment. The positive rate of blocking antibody (BA), pregnancy success rate, and preterm birth rate were counted. RESULT: After treatment, the total score of TCM syndromes, IL-2 level, and Th1/Th2 ratio in the two groups decreased significantly, while the levels of IL-10, hCG, and P increased significantly, and the study group improved significantly compared with the control group (P < 0.05). The positive rate of BA and pregnancy success rate in the study group were higher than those in the control group (P < 0.05). There was no significant difference in the preterm birth rate between the two groups (P > 0.05). CONCLUSION: On the basis of routine western medicine treatment, a combined application of Bushen Tiaochong cycle therapy can significantly improve the Th1/Th2 deviation, serum sex hormone level, and pregnancy outcome in patients with alloimmune RSA.

11.
Plant Cell Environ ; 44(12): 3563-3575, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34536020

RESUMO

The flagellin epitope flg22, a pathogen-associated molecular pattern (PAMP), binds to the receptor-like kinase FLAGELLIN SENSING2 (FLS2), and triggers Ca2+ influx across the plasma membrane (PM). The flg22-induced increases in cytosolic Ca2+ concentration ([Ca2+ ]i ) (FICA) play a crucial role in plant innate immunity. It's well established that the receptor FLS2 and reactive oxygen species (ROS) burst undergo sensitivity adaptation after flg22 stimulation, referred to as desensitization and resensitization, to prevent over responses to pathogens. However, whether FICA also mount adaptation mechanisms to ensure appropriate and efficient responses against pathogens remains poorly understood. Here, we analysed systematically [Ca2+ ]i increases upon two successive flg22 treatments, recorded and characterized rapid desensitization but slow resensitization of FICA in Arabidopsis thaliana. Pharmacological analyses showed that the rapid desensitization might be synergistically regulated by ligand-induced FLS2 endocytosis as well as the PM depolarization. The resensitization of FICA might require de novo FLS2 protein synthesis. FICA resensitization appeared significantly slower than FLS2 protein recovery, suggesting additional regulatory mechanisms of other components, such as flg22-related Ca2+ permeable channels. Taken together, we have carefully defined the FICA sensitivity adaptation, which will facilitate further molecular and genetic dissection of the Ca2+ -mediated adaptive mechanisms in PAMP-triggered immunity.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Cálcio/metabolismo , Endocitose/genética , Regulação da Expressão Gênica de Plantas , Proteínas Quinases/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Ligantes , Proteínas Quinases/metabolismo
12.
Science ; 373(6553): 420-425, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34140391

RESUMO

Plant nucleotide-binding leucine-rich repeat receptors (NLRs) regulate immunity and cell death. In Arabidopsis, a subfamily of "helper" NLRs is required by many "sensor" NLRs. Active NRG1.1 oligomerized, was enriched in plasma membrane puncta, and conferred cytoplasmic calcium ion (Ca2+) influx in plant and human cells. NRG1.1-dependent Ca2+ influx and cell death were sensitive to Ca2+ channel blockers and were suppressed by mutations affecting oligomerization or plasma membrane enrichment. Ca2+ influx and cell death mediated by NRG1.1 and ACTIVATED DISEASE RESISTANCE 1 (ADR1), another helper NLR, required conserved negatively charged N-terminal residues. Whole-cell voltage-clamp recordings demonstrated that Arabidopsis helper NLRs form Ca2+-permeable cation channels to directly regulate cytoplasmic Ca2+ levels and consequent cell death. Thus, helper NLRs transduce cell death signals directly.


Assuntos
Proteínas de Arabidopsis/química , Canais de Cálcio/química , Cálcio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/química , Proteínas NLR/química , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Morte Celular , Membrana Celular/metabolismo , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas NLR/metabolismo , Técnicas de Patch-Clamp , Domínios Proteicos , Estrutura Secundária de Proteína
13.
Phytother Res ; 35(7): 3799-3811, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33763888

RESUMO

Sclerosing cholangitis, characterized by biliary inflammation, fibrosis, and stricturing, remains one of the most challenging conditions of clinical hepatology. Geniposide (GE) has anti-inflammatory, hepatoprotective, and cholagogic effects. Whether GE provides inhibition on the development of sclerosing cholangitis is unknown. Here, we investigated the role of GE in a mouse model in which mice were fed with 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) for 4 weeks to induce sclerosing cholangitis. The results demonstrated that the increased hepatic gene expressions of pro-inflammatory (IL-6, VCAM-1, MCP-1, and F4/80) and profibrogenic markers (Col1α1, Col1α2, TGF-ß, and α-SMA) in DDC feeding mice were reversed after treatment with GE. GE also suppressed expressions of CK19 and Ki67 in DDC-fed mice, suggesting that GE could ameliorate DDC-induced hepatocytes and cholangiocytes proliferation. In addition, GE significantly increased bile acids (BAs) secretion in bile, which correlated with induced expressions of hepatic FXR, BAs secretion transporters (BSEP, MRP2, MDR1, and MDR2), and reduced CYP7A1 mRNA expression. Furthermore, higher expressions of ileal FXR-FGF15 signaling and reduced ASBT were also observed after GE treatment. Taken together, these data showed that GE could modulate inflammation, fibrosis, and BAs homeostasis in DDC-fed mice, which lead to efficiently delay the progression of sclerosing cholangitis.


Assuntos
Colangite Esclerosante , Iridoides , Animais , Colangite Esclerosante/induzido quimicamente , Colangite Esclerosante/tratamento farmacológico , Modelos Animais de Doenças , Iridoides/farmacologia , Fígado/efeitos dos fármacos , Camundongos , Camundongos Knockout
14.
J Mol Endocrinol ; 66(1): R15-R21, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33434146

RESUMO

Discovered as a b-ZIP transcription repressor 30 years ago, E4 promoter-binding protein 4 (E4BP4) has been shown to play critical roles in immunity, circadian rhythms, and cancer progression. Recent research has highlighted E4BP4 as a novel regulator of metabolisms in various tissues. In this review, we focus on the function and mechanisms of hepatic E4BP4 in regulating lipid and glucose homeostasis, bile metabolism, as well as xenobiotic metabolism. Finally, E4BP4-specific targets will be discussed for the prevention and treatment of metabolic disorders.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Metabolismo Energético , Fígado/metabolismo , Animais , Ácidos e Sais Biliares/metabolismo , Núcleo Celular/metabolismo , Glucose/metabolismo , Humanos , Insulina/metabolismo , Metabolismo dos Lipídeos
15.
J Ethnopharmacol ; 271: 113855, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33485979

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellarin (Scu) is one of the main active ingredients of Erigeron breviscapus (Vant.) Hand.-Mazz which has been used to treat cardiovascular disease including vascular dysfunction caused by diabetes. Scu also has a protective effect on vascular endothelial cells against hyperglycemia. However, molecular mechanisms underlying this effect are not clear. AIM OF THE STUDY: This aim of this study was to investigate the effect of Scu on human umbilical vein endothelial cells (HUVECs) injury induced by high glucose (HG), especially the regulation of PTEN-induced kinase 1 (PINK1)/Parkin-mediated mitophagy. MATERIALS AND METHODS: HUVECs were exposed to HG to induce vascular endothelial cells injury in vitro. Cell viability was assessed by MTT assay. The extent of cell apoptosis was measured by Hoechst staining and flow cytometry. Mitophagy was assayed by fluorescent immunostaining, transmission electron microscope and immunoblot. Besides, virtual docking was conducted to validate the interaction of PINK1 protein and Scu. RESULTS: We found that Scu significantly increased cell viability in HG-treated HUVECs. Scu reduces the expression of Bcl-2, Bax and cytochrome C (Cyt.c) to inhibit apoptosis through a mitochondria-dependent pathway. Meanwhile, Scu improved the overload of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and SOD2 protein expression, and reversed the collapse of mitochondrial membrane potential. Besides, Scu increased autophagic flux, improved the expression of microtubule-associated protein 1 light chain 3 Ⅱ (LC3 II), Beclin 1 and autophagy-related gene 5 (Atg 5) and decreased the expression of Sequestosome1/P62 in HG-treated HUVECs. Furthermore, Scu improved the expressions of PINK1, Parkin, and Mitofusin2, which revealed the enhancement of mitophagy. Moreover, the beneficial effects of Scu on HG-induced low expression of Parkin, overproduction of ROS, and over expressions of P62, Cyt.c and Cleaved caspase-3 were weakened by PINK1 gene knockdown. Molecular docking suggested good interaction of Scu and PINK1 protein. CONCLUSION: These results suggest that Scu may protect vascular endothelial cells against hyperglycemia-induced injury by up-regulating mitophagy via PINK1/Parkin signal pathway.


Assuntos
Apigenina/farmacologia , Glucuronatos/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Mitofagia/efeitos dos fármacos , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Apigenina/química , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Angiopatias Diabéticas/tratamento farmacológico , Angiopatias Diabéticas/metabolismo , Inativação Gênica , Glucose/toxicidade , Glucuronatos/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Hiperglicemia/induzido quimicamente , Hiperglicemia/complicações , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitofagia/genética , Simulação de Acoplamento Molecular , Estresse Oxidativo/efeitos dos fármacos , Proteínas Quinases/química , Proteínas Quinases/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
16.
Oncol Lett ; 20(1): 346-356, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32537024

RESUMO

Standard chemotherapy is commonly used in clinical practice for the treatment of non-small cell lung cancer (NSCLC). However, its therapeutic efficacy remains low. Combination therapy for cancer treatment has attracted attention in recent years. The present study aimed to investigate the antitumor effect of the combination treatment with gemcitabine and sorafenib on NSCLC in vitro and in vivo, and to determine its underlying molecular mechanisms. The anti-NSCLC effects of combination therapy were analyzed by flow cytometry analysis, MTT, western blotting, reverse transcription-quantitative PCR, wound healing and Transwell invasion assays. A549 cells subjected to combination treatment with gemcitabine and sorafenib demonstrated a more irregular cellular morphology and lower cell viability compared with the monotherapy groups. Combination of gemcitabine and sorafenib significantly induced cell cycle arrest and apoptosis in A549 cells. Additionally, combination therapy was demonstrated to restrain the migration and invasion of tumor cells by suppressing epithelial-to-mesenchymal transition (EMT) of A549 cells. In vivo analyses confirmed that co-treatment with gemcitabine and sorafenib decreased NSCLC tumor growth and tumor weight in nude mice. Taken together, the results of the present study suggested that combination treatment with gemcitabine and sorafenib exerted a synergistic inhibitory effect on NSCLC in vitro and in vivo via the EMT process.

17.
Int J Nanomedicine ; 15: 1661-1675, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210559

RESUMO

BACKGROUND: Breviscapine (BRE) has significant efficacy in cardiovascular disease, but the poor water solubility of breviscapine affects its oral absorption and limits its clinical application. In this study, supercritical carbon dioxide (SCF-CO2) technology was used to improve the solubility and bioavailability of BRE loaded into mesoporous silica nanoparticles (MSNs). METHODS: The solubility of BRE in SCF-CO2 was measured under various conditions to investigate the feasibility of preparing drug-loaded MSNs by using ultrasound-assisted solution-enhanced dispersion by supercritical fluids (USEDS). The preparation process of drug-loaded MSNs was optimized using the central composite design (CCD), and the optimized preparation was comprehensively characterized. Furthermore, the drug-loaded MSNs prepared by the conventional method were compared. Finally, the dissolution and bioavailability of the preparations were evaluated by in vitro release and pharmacokinetics study. RESULTS: The solubility of BRE in SCF-CO2 was extremely low which was suitable to prepare BRE-loaded MSNs by USEDS technology. The particle size of the preparation was 177.24 nm, the drug loading was 8.63%, and the specific surface area was 456.3m2/g. As compared to the conventional preparation method of solution impregnation-evaporation (SIV), the formulation prepared by USEDS technology has smaller particle size, higher drug loading, less residual solvent and better stability. The results of the in vitro release study showed that drug-loaded MSNs could significantly improve drug dissolution. The results of pharmacokinetics showed that the bioavailability of drug-loaded MSNs was increased 1.96 times compared to that of the BRE powder. CONCLUSION: Drug-loaded MSNs can significantly improve the solubility and bioavailability of BRE, indicating a good application prospect for MSNs in improving the oral absorption of drugs. In addition, as a solid dispersion preparation technology, USEDS technology has incomparable advantages.


Assuntos
Flavonoides/farmacologia , Nanopartículas/química , Dióxido de Silício/química , Ultrassom , Adsorção , Animais , Disponibilidade Biológica , Células CACO-2 , Varredura Diferencial de Calorimetria , Morte Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Humanos , Masculino , Modelos Teóricos , Nanopartículas/ultraestrutura , Nitrogênio/química , Ratos Wistar , Solubilidade , Soluções , Solventes
18.
Nature ; 578(7796): 577-581, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32076270

RESUMO

Hydrogen peroxide (H2O2) is a major reactive oxygen species in unicellular and multicellular organisms, and is produced extracellularly in response to external stresses and internal cues1-4. H2O2 enters cells through aquaporin membrane proteins and covalently modifies cytoplasmic proteins to regulate signalling and cellular processes. However, whether sensors for H2O2 also exist on the cell surface remains unknown. In plant cells, H2O2 triggers an influx of Ca2+ ions, which is thought to be involved in H2O2 sensing and signalling. Here, by using forward genetic screens based on Ca2+ imaging, we isolated hydrogen-peroxide-induced Ca2+ increases (hpca) mutants in Arabidopsis, and identified HPCA1 as a leucine-rich-repeat receptor kinase belonging to a previously uncharacterized subfamily that features two extra pairs of cysteine residues in the extracellular domain. HPCA1 is localized to the plasma membrane and is activated by H2O2 via covalent modification of extracellular cysteine residues, which leads to autophosphorylation of HPCA1. HPCA1 mediates H2O2-induced activation of Ca2+ channels in guard cells and is required for stomatal closure. Our findings help to identify how the perception of extracellular H2O2 is integrated with responses to various external stresses and internal cues in plants, and have implications for the design of crops with enhanced fitness.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Peróxido de Hidrogênio/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Cisteína/química , Cisteína/metabolismo , Ativação Enzimática , Proteínas de Membrana/química , Proteínas de Membrana/genética , Mutação , Oxirredução , Células Vegetais/metabolismo , Domínios Proteicos , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética
19.
Phytother Res ; 34(6): 1455-1466, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31828866

RESUMO

High levels of consumption of saturated lipids have been largely associated with the increasing prevalence of metabolic diseases. In particular, saturated fatty acids such as palmitic acid (PA) have been implicated in the development of insulin resistance (IR). Scutellarin (Scu) is one of the effective traditional Chinese medicines considered beneficial for liver diseases and diabetes. In this study, we investigated the effect of Scu on IR and lipid metabolism disorders in vitro and in high fat diet (HFD)-fed mice. In vitro, we found that Scu decreased insulin-dependent lipid accumulation and the mRNA expression of CD36, Fasn, and ACC in PA-treated HepG2 cells. Additionally, Scu upregulated Akt phosphorylation and improved the insulin signalling pathway. Moreover, Scu downregulated mammalian target of rapamycin (mTOR) phosphorylation and the n-SREBP-1c protein level and also reduced lipid accumulation via the mTOR-dependent pathway, as confirmed by the molecular docking of Scu to mTOR. In HFD-fed C57BL/6 mice, Scu improved oral glucose tolerance, pyruvate tolerance and the IR index and also increased the Akt phosphorylation level. Moreover, Scu reduced hepatocyte steatosis, decreased lipid accumulation and triglyceride levels, inhibited mTOR phosphorylation, and decreased the SREBP-1c level in the liver. Taken together, these findings suggest that Scu ameliorates hepatic IR by regulating hepatocyte lipid metabolism via the mTOR-dependent pathway through SREBP-1c suppression.


Assuntos
Apigenina/uso terapêutico , Glucuronatos/uso terapêutico , Hepatócitos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Simulação de Acoplamento Molecular/métodos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Serina-Treonina Quinases TOR/efeitos dos fármacos , Animais , Apigenina/farmacologia , Técnicas de Cultura de Células , Glucuronatos/farmacologia , Humanos , Masculino , Camundongos
20.
Minerva Chir ; 75(1): 25-29, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30600962

RESUMO

BACKGROUND: This study aims to investigate the impacts of preoperative maximum detrusor pressure (Pdet.max) on minimally invasive surgery effect on patients with benign prostatic hyperplasia. METHODS: The clinical data of a total of 156 patients receiving minimally invasive surgery for benign prostatic hyperplasia in Hospital of Nanchang Institute of Medical Sciences from August 2014 to June 2017 were retrospectively reviewed and summarized. The patients were divided into three groups according to different Pdet.max in the urodynamic examination results before the surgery, namely, group A (Pdet.max <50 cmH2O), group B (50≤ Pdet.max <90 cmH2O) and group C (Pdet.max ≥90 cmH2O). The International Prostate Symptom Score (IPSS) and Quality-of-Life score (QOLS) were compared. RESULTS: Compared with those in group A, the IPSS and QOLS of the patients in group B and group C at 1 month, 3 months and 12 months after the surgery were decreased notably (all P<0.05). Moreover, the IPSS and QOLS of the patients in group C were obviously lower than those in group B (all P<0.05). CONCLUSIONS: The results indicated that as the preoperative Pdet.max was increased, the symptoms of the patients receiving minimally invasive surgery for benign prostatic hyperplasia were ameliorated more significantly, and the patients had higher quality of life. The preoperative Pdet.max can judge the treatment effect of minimally invasive surgery on the patients with benign prostatic hyperplasia and help to guide the patients' prognosis. The greater the preoperative Pdet.max is, the better the treatment effect of the patients after the surgery will be, and the higher the quality of life will be.


Assuntos
Músculo Liso/fisiopatologia , Hiperplasia Prostática/cirurgia , Bexiga Urinária/fisiopatologia , Idoso , Estatura , Peso Corporal , Humanos , Masculino , Estado Civil , Procedimentos Cirúrgicos Minimamente Invasivos , Período Pré-Operatório , Pressão , Hiperplasia Prostática/fisiopatologia , Qualidade de Vida , Estudos Retrospectivos , Avaliação de Sintomas , Resultado do Tratamento
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