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1.
Acta Pharmacol Sin ; 44(12): 2388-2403, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37580494

RESUMO

Diabetic peripheral neuropathy (DPN) is a common complication of diabetes, which has yet no curable medication. Neuroinflammation and mitochondrial dysfunction are tightly linked to DPN pathology. G-protein-coupled receptor 40 (GPR40) is predominantly expressed in pancreatic ß-cells, but also in spinal dorsal horn and dorsal root ganglion (DRG) neurons, regulating neuropathic pain. We previously have reported that vincamine (Vin), a monoterpenoid indole alkaloid extracted from Madagascar periwinkle, is a GPR40 agonist. In this study, we evaluated the therapeutic potential of Vin in ameliorating the DPN-like pathology in diabetic mice. Both STZ-induced type 1 (T1DM) and db/db type 2 diabetic (T2DM) mice were used to establish late-stage DPN model (DPN mice), which were administered Vin (30 mg·kg-1·d-1, i.p.) for 4 weeks. We showed that Vin administration did not lower blood glucose levels, but significantly ameliorated neurological dysfunctions in DPN mice. Vin administration improved the blood flow velocities and blood perfusion areas of foot pads and sciatic nerve tissues in DPN mice. We demonstrated that Vin administration protected against sciatic nerve myelin sheath injury and ameliorated foot skin intraepidermal nerve fiber (IENF) density impairment in DPN mice. Moreover, Vin suppressed NLRP3 inflammasome activation through either ß-Arrestin2 or ß-Arrestin2/IκBα/NF-κB signaling, improved mitochondrial dysfunction through CaMKKß/AMPK/SIRT1/PGC-1α signaling and alleviated oxidative stress through Nrf2 signaling in the sciatic nerve tissues of DPN mice and LPS/ATP-treated RSC96 cells. All the above-mentioned beneficial effects of Vin were abolished by GPR40-specific knockdown in dorsal root ganglia and sciatic nerve tissues. Together, these results support that pharmacological activation of GPR40 as a promising therapeutic strategy for DPN and highlight the potential of Vin in the treatment of this disease.


Assuntos
Diabetes Mellitus Experimental , Neuropatias Diabéticas , Vincamina , Animais , Camundongos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/patologia , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Monoterpenos/química , Monoterpenos/farmacologia , Receptores Acoplados a Proteínas G , Nervo Isquiático/patologia , Transdução de Sinais , Vincamina/farmacologia , Vincamina/uso terapêutico
2.
Biol Reprod ; 107(4): 1026-1034, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-35774023

RESUMO

G protein-coupled estrogen receptor (GPER), a seven-transmembrane G protein-coupled receptor, mediates the rapid pre-genomic signaling actions of estrogen and derivatives thereof. The expression of GPER is extensive in mammal male reproductive system. However, the functional role of GPER in mouse sperm has not yet been well recognized. This study revealed that GPER was expressed at the acrosome and the mid-flagellum of the mouse sperm. The endogenous GPER ligand 17ß-estradiol and the selective GPER agonist G1 increased intracellular Ca2+ concentration ([Ca2+]i) in mouse sperm, which could be abolished by G15, an antagonist of GPER. In addition, the G1-stimulated Ca2+ response was attenuated by interference with the phospholipase C (PLC) signaling pathways or by blocking the cation channel of sperm (CatSper). Chlortetracycline staining assay showed that the activation of GPER increased the incidence of acrosome-reacted sperm. Conclusively, GPER was located at the acrosome and mid-flagellum of the mouse sperm. Activation of GPER triggered the elevation of [Ca2+]i through PLC-dependent Ca2+ mobilization and CatSper-mediated Ca2+ influx, which promoted the acrosome reaction of mouse sperm.


Assuntos
Reação Acrossômica , Clortetraciclina , Animais , Cálcio/metabolismo , Clortetraciclina/metabolismo , Estradiol/metabolismo , Estrogênios/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Ligantes , Masculino , Mamíferos/metabolismo , Camundongos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Sêmen/metabolismo , Espermatozoides/metabolismo , Fosfolipases Tipo C/metabolismo
3.
Am J Physiol Cell Physiol ; 319(4): C630-C640, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32726160

RESUMO

The neurohypophyseal hormone oxytocin (OT) plays critical roles in lactation and parturition, while its function in male reproduction system is largely unknown. This study aims to investigate the effect of OT on regulating transepithelial ion transport in rat cauda epididymal epithelium. With the use of RT-PCR, Western blot, and immunohistochemical analysis, we found that OT receptor (OTR) was expressed and localized at the basal membrane of rat cauda epididymal epithelium. The short-circuit current (Isc) measurement showed that basolateral application of OT to the primary cultured rat cauda epididymal epithelial cells elicited an increase in Isc, which was abrogated by pretreating the epithelial cells with CFTRinh-172, a blocker of cystic fibrosis transmembrane conductance regulator (CFTR). Pretreatment with the prostaglandin H synthase inhibitors indomethacin and piroxicam, or the nonselective antagonists of prostaglandin E2 (PGE2) receptor EP2 or EP4, AH-6809, and AH-23848, significantly attenuated OT-stimulated Isc response. Furthermore, the generation of PGE2 was measured using enzyme-linked immunosorbent assay, demonstrating that OT induced a substantial increase in PGE2 release from primary cultured rat cauda epididymal epithelial cells. In conclusion, activation of OTR by OT triggered PGE2 release, resulting in CFTR-dependent Cl- secretion through paracrine/autocrine pathways in rat cauda epididymal epithelium.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Dinoprostona/genética , Ocitocina/genética , Receptores de Ocitocina/genética , Animais , Comunicação Autócrina/efeitos dos fármacos , Compostos de Bifenilo/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Epididimo/efeitos dos fármacos , Epididimo/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Lactação/genética , Masculino , Comunicação Parácrina/efeitos dos fármacos , Cultura Primária de Células , Ratos
4.
5.
Nitric Oxide ; 100-101: 30-37, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32283263

RESUMO

Epididymal epithelium possesses active ion transport properties conducive to the maintenance of appropriate epididymal intraluminal microenvironment. The endogenous gasotransmitter carbon monoxide (CO) regulates numerous cellular processes including water and electrolyte transport in various epithelia. However, the functional role of CO in epididymal epithelium is still elusive. This study aims to explore the potential regulatory effect of CO on transepithelial ion transport in rat epididymis. Using qPCR technique, we verified that endogenous CO synthase heme oxygenase 1 was expressed in rat caput, corpus, and cauda epididymis. In addition, endogenous CO was detected in rat cauda epididymis. Ussing chamber experiments showed that CORM-2, a CO donor, induced an increase of the short-circuit current (ISC) in a concentration-dependent manner in rat cauda epididymal epithelium. The ISC response could be abrogated by removing the ambient Cl- or HCO3-. Interfering with the cAMP signaling pathway or blocking cystic fibrosis transmembrane regulator (CFTR) partially suppressed the CO-stimulated ISC response. Moreover, the CO-evoked ISC response was significantly attenuated by blocking Ca2+-activated Cl- channel (CaCC) or chelating intracellular Ca2+. Elevation of intracellular Ca2+ level was also observed after CO stimulation in rat cauda epididymal epithelial cells. Collectively, this study demonstrated that CO stimulated anion secretion via activation of CFTR and CaCC in rat cauda epididymal epithelium, which might contribute to the formation of the appropriate microenvironment essential for sperm storage.


Assuntos
Monóxido de Carbono/metabolismo , Epididimo/fisiologia , Epitélio/fisiologia , Transporte de Íons/fisiologia , Animais , Canais de Cloreto/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Epididimo/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Heme Oxigenase (Desciclizante)/metabolismo , Transporte de Íons/efeitos dos fármacos , Masculino , Compostos Organometálicos/farmacologia , Ratos Sprague-Dawley
6.
J Cell Physiol ; 234(9): 15790-15799, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30697740

RESUMO

The vagina provides a characteristic low-Na+ and low-pH fluid microenvironment that is considered generally protective. Previous studies have shown that various types of epithelial cells harbor the capacity of intracellular pH (pHi) regulation. However, it remains elusive whether vaginal epithelium could actively regulate pHi by transporting acid-base ions. In this study, we verified that after transient exposure to NH4 Cl, the pHi values could rapidly recover from acidification via Na+ -H+ exchanger (NHE), Na+ -HCO3 - cotransporter (NBC), and carbonic anhydrase in human vaginal epithelial cell line VK2/E6E7. Positive expression of the main acid-base transporters including NHE1-2, NBCe1-2, and NBCn1 mRNA was also detected in VK2/E6E7 cells. Moreover, the in vivo study further showed that interfering with the function of V-type H+ -ATPase, NHE or NBC expressed in vagina impaired vaginal luminal pH homeostasis in rats. Taken together, our study reveals the property of pH regulation in vaginal epithelial cells, which might provide novel insights into the potential role of vaginal epithelium in the formation of the vaginal acidic microenvironment.

7.
J Neurochem ; 151(5): 595-607, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31520526

RESUMO

High-mobility group box-1 (HMGB-1) acts as a pro-inflammatory cytokine contributing to the occurrence of many central inflammatory and infectious disorders. Brain mast cells (MCs) are the first responders to peripheral inflammatory stimulation because of their rapid response to external stimuli coupled with their release of preformed and newly synthesized reactive chemicals. Little is known about the involvement of brain MCs in the pro-inflammatory effects of HMGB-1 on the central nervous system (CNS). Thus, we investigated the activation process of MCs by HMGB-1 and explored whether this process is involved in the pro-inflammatory effects of HMGB-1 on the CNS. In this study, we used P815 cells to study the activating role of HMGB-1 on MCs and to explore its potential mechanism in vitro. In an in vivo study, adult male Sprague-Dawley rats received i.c.v. injection of sterile saline or cromoglycate (stabilizer of MCs) 30 min prior to i.p. injection of HMGB-1. Increased levels of tumor necrosis factor and IL-1ß were observed in the P815 cells, as well as in the rats' brains, after HMGB-1 treatment. Pretreatment with the receptor of advanced glycation endproducts (RAGE)-siRNA inhibited the HMGB-1-induced inflammatory process in the P815 cells. Activation of the RAGE/nuclear factor-κB (NF-κB) pathway was observed in both the P815 cells and rats' brains. In addition, HMGB-1 induced the accumulation of brain MCs in the hippocampal CA1 region, and the blood-brain barrier was disrupted. Pretreatment with cromoglycate, a stabilizer of MCs, mitigated these HMGB-1-induced pro-inflammatory processes in rats. These findings indicate that brain MCs are involved in the pro-inflammatory effect of HMGB-1 on the CNS, probably via activating the RAGE/NF-κB pathway.


Assuntos
Encéfalo/imunologia , Proteína HMGB1/imunologia , Mastócitos/imunologia , Transdução de Sinais/imunologia , Animais , Encéfalo/metabolismo , Proteína HMGB1/metabolismo , Masculino , Mastócitos/metabolismo , Camundongos , NF-kappa B/imunologia , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada/imunologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo
8.
Nitric Oxide ; 90: 37-46, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31175932

RESUMO

Endometrial epithelium exhibits a robust ion transport activity required for dynamical regulation of uterine fluid environment and thus embryo implantation. However, there still lacks a thorough understanding of the ion transport processes and regulatory mechanism in peri-implantation endometrial epithelium. As a gaseous signaling molecule or gasotransmitter, hydrogen sulfide (H2S) regulates a myriad of cellular and physiological processes in various tissues, including the modulation of ion transport proteins in epithelium. This study aimed to investigate the effects of H2S on ion transport across mouse endometrial epithelium and its possible role in embryo implantation. The existence of endogenous H2S in pregnant mouse uterus was tested by the detection of two key H2S-generating enzymes and measurement of H2S production rate in tissue homogenates. Transepithelial ion transport processes were electrophysiologically assessed in Ussing chambers on early pregnant mouse endometrial epithelial layers, demonstrating that H2S suppressed the anion secretion by blocking cystic fibrosis transmembrane conductance regulator (CFTR). H2S increased intracellular Cl- concentration ([Cl-]i) in mouse endometrial epithelial cells, which was abolished by pretreatment with the CFTR selective inhibitor CFTRinh-172. The cAMP level in mouse endometrial epithelial cells was not affected by H2S, indicating that H2S blocked CFTR in a cAMP-independent way. In vivo study showed that interference with H2S synthesis impaired embryo implantation. In conclusion, our study demonstrated that H2S inhibits the transepithelial anion secretion of early pregnant mouse endometrial epithelium via blockade of CFTR, contributing to the preparation for embryo implantation.


Assuntos
Endométrio/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Gasotransmissores/farmacologia , Sulfeto de Hidrogênio/farmacologia , Animais , Ânions/antagonistas & inibidores , Ânions/metabolismo , Transporte Biológico/efeitos dos fármacos , Endométrio/metabolismo , Células Epiteliais/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Gravidez
9.
Cell Physiol Biochem ; 44(3): 1146-1160, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29179179

RESUMO

BACKGROUND/AIMS: Sputum symptoms are commonly seen in the elderly. This study aimed to identify an efficacious expectorant treatment stratagem through evaluating the secretion-promoting activation and cystic fibrosis transmembrane conductance regulator (CFTR) expression of the bioactive herbal monomer naringenin. METHODS: Vectorial Cl- transport was determined by measuring short-circuit current (ISC) in rat airway epithelium. cAMP content was measured by ELISA in primary cultured epithelial cells and Calu-3 cells. CFTR expression in Calu-3 cells was determined by qPCR. RESULTS: Addition of naringenin to the basolateral side of the rat airway led to a concentration-dependent sustained increase in ISC. The current was suppressed when exposed to Cl--free solution or by bumetanide, BaCl2, and DPC but not by DIDS and IBMX. Forskolin-induced ISC increase and CFTRinh-172/MDL-12330A-induced ISC inhibition were not altered by naringenin. Intracellular cAMP content was significantly increased by naringenin. With lipopolysaccharide stimulation, CFTR expression was significantly reduced, and naringenin dose-dependently enhanced CFTR mRNA expression. CONCLUSION: These results demonstrate that naringenin has the ability to stimulate Cl- secretion, which is mediated by CFTR through a signaling pathway by increasing cAMP content. Moreover, naringenin can increase CFTR expression when organism CFTR expression is seriously hampered. Our data suggest a potentially effective treatment strategy for sputum.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Células Epiteliais/efeitos dos fármacos , Flavanonas/farmacologia , Animais , Compostos de Bário/farmacologia , Benzoatos/farmacologia , Células Cultivadas , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/metabolismo , Cloretos/farmacologia , Colforsina/farmacologia , AMP Cíclico/análise , Regulador de Condutância Transmembrana em Fibrose Cística/antagonistas & inibidores , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Humanos , Iminas/farmacologia , Transporte de Íons/efeitos dos fármacos , Masculino , Microscopia de Fluorescência , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Tiazolidinas/farmacologia , Traqueia/citologia , ortoaminobenzoatos/farmacologia
10.
Biochem Biophys Res Commun ; 487(3): 517-524, 2017 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-28412354

RESUMO

Several studies have implicated estrogen and the estrogen receptor (ER) in the pathogenesis of benign prostatic hyperplasia (BPH); however, the mechanism underlying this effect remains elusive. In the present study, we demonstrated that estrogen (17ß-estradiol, or E2)-induced activation of the G protein-coupled receptor 30 (GPR30) triggered Ca2+ release from the endoplasmic reticulum, increased the mitochondrial Ca2+ concentration, and thus induced prostate epithelial cell (PEC) apoptosis. Both E2 and the GPR30-specific agonist G1 induced a transient intracellular Ca2+ release in PECs via the phospholipase C (PLC)-inositol 1, 4, 5-triphosphate (IP3) pathway, and this was abolished by treatment with the GPR30 antagonist G15. The release of cytochrome c and activation of caspase-3 in response to GPR30 activation were observed. Data generated from the analysis of animal models and human clinical samples indicate that treatment with the GPR30 agonist relieves testosterone propionate (TP)-induced prostatic epithelial hyperplasia, and that the abundance of GPR30 is negatively associated with prostate volume. On the basis of these results, we propose a novel regulatory mechanism whereby estrogen induces the apoptosis of PECs via GPR30 activation. Inhibition of this activation is predicted to lead to abnormal PEC accumulation, and to thereby contribute to BPH pathogenesis.


Assuntos
Apoptose/efeitos dos fármacos , Estrogênios/farmacologia , Próstata/efeitos dos fármacos , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/patologia , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Benzodioxóis/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cães , Relação Dose-Resposta a Droga , Humanos , Masculino , Camundongos , Próstata/citologia , Hiperplasia Prostática/metabolismo , Quinolinas/farmacologia , Receptores de Estrogênio/antagonistas & inibidores , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/genética , Relação Estrutura-Atividade
11.
J Neuroinflammation ; 14(1): 233, 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29179727

RESUMO

BACKGROUND: Neuroinflammation, which ultimately leads to neuronal loss, is considered to play a crucial role in numerous neurodegenerative diseases. The neuroinflammatory process is characterized by the activation of glial cells such as microglia. Endoplasmic reticulum (ER) stress is commonly associated with impairments in neuronal function and cognition, but its relationship and role in neurodegeneration is still controversial. Recently, it was confirmed that nonharmful levels of ER stress protected against experimental Parkinson's disease. Here, we investigated mild ER stress-based regulation of lipopolysaccharide (LPS)-driven neuroinflammation in rats and in primary microglia. METHODS: Male Sprague-Dawley (SD) rats received the intracerebroventricular injection of the ER stress activator tunicamycin (TM) with or without intraperitoneal injection of the ER stress stabilizer sodium 4-phenylbutyrate (4-PBA) 1 h before LPS administration. The levels of neuroinflammation and memory dysfunction were assessed 24 h after treatment. In addition, the effect of mild ER stress on microglia was determined in vitro. RESULTS: Here, we found that low doses of TM led to mild ER stress without cell or organism lethality. We showed that mild ER stress preconditioning reduced microglia activation and neuronal death as well as improved LPS-induced memory impairment in rats. In addition, pre-exposure to nonlethal doses of TM in microglia showed significant protection against LPS-induced proinflammatory cytokine production and M1/2b polarization. However, sodium 4-PBA, a compound that ameliorates ER stress, ablated this protective effect in vivo and in vitro. CONCLUSIONS: Based on our findings, we conclude that the mild ER stress not only limits the accumulation of misfolded proteins but also protects tissues from harmful endotoxemia insults. Therefore, ER stress preconditioning has potential therapeutic value for the treatment of neurodegenerative diseases.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Inflamação/fisiopatologia , Microglia/metabolismo , Animais , Inflamação/induzido quimicamente , Lipopolissacarídeos/toxicidade , Masculino , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/fisiopatologia , Degeneração Neural/fisiopatologia , Ratos , Ratos Sprague-Dawley
12.
Planta Med ; 83(7): 624-630, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27936472

RESUMO

Sodium tanshinone IIA sulphonate, a water-soluble derivative of tanshinone IIA, has been proven to possess versatile biological properties, but its pharmacological effect on tracheal smooth muscle remains elusive. This paper presents a study on the relaxant effect and underlying mechanisms of sodium tanshinone IIA sulphonate on mouse tracheal smooth muscle. The relaxant effect of sodium tanshinone IIA sulphonate was evaluated in mouse tracheal rings using a mechanical recording system. Intracellular Ca2+ concentration was measured in primary cultured tracheal smooth muscle cells using confocal imaging system. The results showed that sodium tanshinone IIA sulphonate induced dose-dependent relaxation of mouse tracheal rings in a ß-adrenoceptor- and epithelium-independent manner. Pretreatment with the ATP-sensitive K+ channel blocker glibenclamide partly attenuated the relaxation response. Administration of sodium tanshinone IIA sulphonate notably inhibited the extracellular Ca2+-induced contraction. High KCl or carbachol-evoked elevation in the intracellular Ca2+ concentration was also abrogated by sodium tanshinone IIA sulphonate in tracheal smooth muscle cells. In conclusion, the tracheal relaxant effect of sodium tanshinone IIA sulphonate was independent of ß-adrenoceptor and airway epithelium, mediated primarily by inhibition of extracellular Ca2+ influx via L-type voltage-dependent Ca2+ channels and partially by activation of the ATP-sensitive K+ channel. These results indicate the potential therapeutic value of sodium tanshinone IIA sulphonate for asthma treatment.


Assuntos
Antiasmáticos/uso terapêutico , Músculo Liso/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Fenantrenos/farmacologia , Salvia miltiorrhiza/química , Animais , Células Cultivadas , Feminino , Masculino , Camundongos , Traqueia
13.
Sci Total Environ ; 915: 170104, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38232826

RESUMO

Phyllostachys pubescens (moso bamboo) has extensively expanded to subtropical broadleaf forests. However, how moso bamboo expansion influences litter-leached dissolved organic matter (DOM) biodegradation is unclear. In this study, we collected fresh leaf litter of moso bamboo and 10 broadleaf tree species from a subtropical forest in southern China and extracted litter-leached dissolved organic carbon (DOC), dissolved total nitrogen (DTN), and dissolved total phosphorus (DTP). Then, using a 42-day incubation experiment, we measured litter-leached DOM biodegradation of the selected 11 species and assessed the relative mixing effects on biodegradation of bamboo litter- and broadleaf tree litter-leached DOM mixtures with volume mixing ratios of 1:3, 1:1, and 3:1. In the litter leachates, bamboo had lower DOC:DTN ratio, DOC:DTP ratio, and DOM aromaticity (i.e., lower SUVA254 and SUVA350 values) than most broadleaf tree species. Litter-leached DOM biodegradation did not differ among bamboo, Liquidambar formosana, Vernicia fordii, and Cyclobalanopsis glauca, but was greater for bamboo than for the other seven broadleaf tree species. Leaf litter-leached DOM biodegradation correlated negatively with DOC:DTN and DOC:DTP ratios, but exhibited no significant relationship with DOM aromaticity. Regardless of volume mixing ratios, antagonistic effects were observed when bamboo litter-leached DOM was mixed with broadleaf tree litter-leached DOM with comparable biodegradation, whereas synergistic effects occurred when bamboo litter-leached DOM was mixed with broadleaf tree litter-leached DOM with lower biodegradation. The relative mixing effects on DOM biodegradation increased linearly with elevated interspecific difference in litter-leached DOM biodegradation between bamboo and broadleaf tree species across the incubation periods. These findings indicate that moso bamboo expansion will substantially alter litter-leached DOM biodegradation by improving substrate quality and changing species interactions, and the magnitudes of such changing trends are dependent on the native tree litter-leached DOM biodegradation in subtropical broadleaf forests.


Assuntos
Matéria Orgânica Dissolvida , Árvores , Árvores/metabolismo , Solo , Carbono/análise , Florestas , Poaceae/metabolismo , China , Nitrogênio
14.
Behav Brain Res ; 472: 115139, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969017

RESUMO

Numerous studies have demonstrated that chronic stress during pregnancy (CSDP) can induce depression and hippocampal damage in offspring. It has also been observed that high levels of corticotropin-releasing hormone (CRH) can damage hippocampal neurons, and intraperitoneal injection of a corticotropin releasing hormone receptor 1 (CRHR1) antagonist decreases depression-like behavior and hippocampal neuronal damage in a mouse depression model. However, whether CSDP causes hippocampal damage and depression in offspring through the interaction of CRH and hippocampal CRHR1 remains unknown and warrants further investigation. Therefore, hippocampal Crhr1 conditional gene knockout mice and C57/BL6J mice were used to study these questions. Depression-related indexs in male offspring mice were examined using the forced swim test (FST), sucrose preference test (SPT), tail suspension test (TST) and open field test (OFT). Serum CRH levels were measured by enzyme-linked immunosorbent assay (ELISA). Golgi-Cox staining was used to examine the morphological changes of hippocampal neuronal dendrites. Neuronal apoptosis in the hippocampal CA3 regions was detected by terminal deoxynucleotidy transferase dUTP nick end labeling (TUNEL) staining. The levels of mammalian target of rapamycin (mTOR), phosphorylated mTOR (p-mTOR) and protein kinase B (AKT) proteins were measured by Western blot analysis. This study showed that CSDP induces depression-like behavior, hippocampal neuronal dendrite damage and apoptosis in male offspring mice. Conditional gene knockout of hippocampal Crhr1 in mice reduced CSDP-induced depression-like behavior, hippocampal neuronal dendrite damage and apoptosis in male offspring, and counteracted the CSDP-induced decreased expression of p-Akt and mTOR activity in male offspring hippocampus. These findings demonstrated that CSDP might inhibit the Akt/mTOR pathway by increasing the levels of CRH, leading to increased CRH-mediated activation of hippocampal CRHR1, thereby inducing synaptic impairment and apoptosis in hippocampal neurons, which in turn leads to depression-like behavior in offspring.

15.
Dev Cell ; 58(1): 63-79.e4, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36626872

RESUMO

Anterior-posterior axis formation regulated by the distal visceral endoderm (DVE) and anterior visceral endoderm (AVE) is essential for peri-implantation embryogenesis. However, the principles of the origin and specialization of DVE and AVE remain elusive. Here, with single-cell transcriptome analysis and pseudotime prediction, we show that DVE and AVE independently originate from the specialized primary endoderm in mouse blastocysts. Along distinct developmental paths, these two lineages, respectively, undergo four representative states with stage-specific transcriptional patterns around implantation. Further comparative analysis shows that AVE, but not DVE, is detected in human and non-human primate embryos, defining differences in polarity formation across species. Moreover, stem cell-assembled human blastoids lack DVE or AVE precursors, implying that additional induction of stem cells with DVE/AVE potential could promote the current embryo-like models and their post-implantation growth. Our work provides insight into understanding of embryonic polarity formation and early mammalian development.


Assuntos
Padronização Corporal , Embrião de Mamíferos , Camundongos , Animais , Humanos , Haplorrinos , Movimento Celular , Endoderma , Regulação da Expressão Gênica no Desenvolvimento , Mamíferos
16.
J Diabetes ; 15(6): 496-507, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37052293

RESUMO

BACKGROUND: Existing evidence concerning the relationship between daytime napping and type 2 diabetes (T2D) is inconsistent, and whether the effects of napping differ by body fat percentage (BFP) and C-reactive protein (CRP) is unclear. We aimed to investigate the association between daytime napping frequency and T2D risk and whether such an association was modified by BFP and CRP. METHODS: We included 435 342 participants free of diabetes from the UK Biobank. Participants were categorized as nonnappers, occasional nappers, and frequent nappers based on napping frequency, and BFP/CRP was divided into quartiles. Cox proportional hazards models were used. RESULTS: During a median follow-up of 9.2 years, 17 592 T2D cases occurred. Higher frequency of daytime napping was significantly associated with an increased risk of T2D. Compared with nonnappers, the adjusted hazard ratios (HRs) for occasional nappers and habitual nappers were 1.28 (95% confidence interval [CI]: 1.24-1.32) and 1.49 (95% CI: 1.41-1.57), respectively. There was a significant additive and multiplicative interaction (relative excess risk due to interaction [RERI] = 0.490, 95% CI 0.307-0.673; p for multiplicative interaction <.001) between napping and BFP, whereby a higher hazard of T2D associated with more frequent napping was greatest among participants in the highest BFP quartile (HR = 4.45, 95% CI: 3.92-5.06). The results for CRP were similar (RERI = 0.266, 95% CI: 0.094-0.439; p for multiplicative interaction <.001). CONCLUSIONS: Higher daytime napping frequency is associated with an increased T2D risk, and such relationships are modified by BFP and CRP. These findings underscore the importance of adiposity and inflammation control to mitigate diabetes risk.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Adiposidade , Bancos de Espécimes Biológicos , Sono , Inflamação/epidemiologia , Obesidade , Proteína C-Reativa/análise , Reino Unido/epidemiologia , Fatores de Risco
17.
J Infect ; 86(1): 47-59, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334726

RESUMO

Toxoplasma gondii is a widespread parasitic protozoan causing toxoplasmosis including pulmonary toxoplasmosis. As the first line of host defense, airway epithelial cells play critical roles in orchestrating pulmonary innate immunity. However, the mechanism underlying the airway inflammation induced by the T. gondii infection remains largely unclear. This study demonstrated that after infection with T. gondii, the major anion channel located in the apical membranes of airway epithelial cells, cystic fibrosis transmembrane conductance regulator (CFTR), was degraded by the parasite-secreted cysteine proteases. The intracellular Cl- concentration ([Cl-]i) was consequently elevated, leading to activation of nuclear factor-κB (NF-κB) signaling via serum/glucocorticoid regulated kinase 1. Furthermore, the heightened [Cl-]i and activated NF-κB signaling could be sustained in a positive feedback regulatory manner resulting from decreased intracellular cAMP level through NF-κB-mediated up-regulation of phosphodiesterase 4. Conversely, the sulfur-containing compound allicin conferred anti-inflammatory effects on pulmonary toxoplasmosis by decreasing [Cl-]i via activation of CFTR. These results suggest that the intracellular Cl- dynamically modulated by T. gondii mediates sustained airway inflammation, which provides a potential therapeutic target against pulmonary toxoplasmosis.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Epitélio , Toxoplasmose , Humanos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Epitélio/metabolismo , Inflamação , Pulmão , NF-kappa B/metabolismo , Toxoplasma
18.
Apoptosis ; 17(5): 492-502, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22307857

RESUMO

CCAAT enhancer binding protein-α (C/EBP-α) is a transcript factor that regulates adipocyte differentiation and induces apoptosis in hepatic stellate cells (HSCs) in vivo and in vitro. However, the effect of C/EBP-α on hepatocytes in vivo remains unknown. This study investigated whether C/EBP-α exerts different apoptotic effects on hepatocytes and HSCs in vitro and in vivo. An adenovirus vector-expressing C/EBP-α gene was constructed, and a rat hepatic stellate cell lines (HSC-T6) and hepatocytes were transfected. A CCl(4)-induced liver fibrosis model in mice was also utilized. C/EBP-α induced apoptosis in hepatocytes and HSCs, but a significant difference between these cell types was observed in vitro. The mitochondrial pathway was involved in the apoptotic process and was predominant in HSC-T6 apoptosis. In the CCl(4)-induced mice liver fibrosis model, the administration of Ad-C/EBP-α decreased extracellular matrix deposition, including collagen and hydroxyproline content, and γ-GT levels, a marker of liver damage, were reduced significantly. Immunohistochemistry and TUNEL assay results showed an increase of apoptosis in HSCs, but hepatocytes were less affected. C/EBP-α induced differential apoptotic effects in hepatocytes and HSCs in vitro and in vivo. This differential effect could be a potential target for the treatment of hepatic fibrosis with little hepatic toxicity.


Assuntos
Apoptose , Proteína alfa Estimuladora de Ligação a CCAAT/fisiologia , Células Estreladas do Fígado/fisiologia , Hepatócitos/fisiologia , Cirrose Hepática/metabolismo , Actinas/metabolismo , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/biossíntese , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Tetracloreto de Carbono , Caspases/genética , Caspases/metabolismo , Células Cultivadas , Colágeno/metabolismo , Fragmentação do DNA , Matriz Extracelular/metabolismo , Expressão Gênica , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Hidroxiprolina/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , gama-Glutamiltransferase/metabolismo
19.
J Pathol ; 223(3): 400-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21171085

RESUMO

The reason for and consequences of BCL2L10 down-regulation in gastric carcinoma are poorly understood. Our aim was to investigate the function of the protein BCL2L10 in gastric carcinoma. We investigated BCL2L10 expression using quantitative real-time PCR and immunoblotting. The methylation status of the BCL2L10 gene promoter was examined by bisulphite sequencing in fresh gastric normal and carcinoma tissues. We studied apoptosis and proliferation regulation in gastric cancer cell lines using flow cytometry, fluorescence staining, murine xenografting and immunoblotting. Pathway inhibitors were applied to confirm the major pathways involved in apoptosis or proliferation regulation. We observed significant correlations between lower BCL2L10 expression and CpG island hypermethylation of the BCL2L10 gene promoter in gastric carcinoma, apoptosis induced by over-expressed BCL2L10 through mitochondrial pathways, and proliferation accelerated by BCL2L10 siRNA via the PI3K-Akt signalling pathway in gastric cancer cell lines. The pro-apoptotic effect of BCL2L10 and growth promotion by BCL2L10 siRNA in gastric cancer cells suggest that it may be a tumour suppressor.


Assuntos
Apoptose/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Neoplasias Gástricas/patologia , Animais , Proliferação de Células , Ilhas de CpG/genética , Metilação de DNA , Feminino , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Camundongos Nus , Mitocôndrias/fisiologia , Transplante de Neoplasias , Fosfatidilinositol 3-Quinases/fisiologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transdução de Sinais/fisiologia , Neoplasias Gástricas/metabolismo , Transplante Heterólogo , Células Tumorais Cultivadas
20.
Int Immunopharmacol ; 109: 108811, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35512563

RESUMO

BACKGROUND: The increasing administration of belimumab has demonstrated its biological benefits. Prior meta-analyses have examined the overall adverse events (AEs) associated with belimumab, but such knowledge needs to be updated with a high volume of new trials. However, little is known about the occurrence of AEs associated with different underlying diseases. This study aimed to address the safety of the intravenous (IV) administration of belimumab combined with standard of care (SoC) therapy in Systemic lupus erythematosus (SLE) patients. METHODS: We used PubMed, Embase, and the Cochrane Library to systematically search for randomised controlled trials (RCTs) reporting AEs and specific AEs in SLE patients receiving belimumab and SoC therapy before 30 November 2021. We extracted the data of the eligible studies and calculated pooled risk ratios (RRs) and their 95% confidence intervals (CIs) in SLE patients receiving belimumab and SoC therapy and experiencing various AEs. The main outcomes were as follows: (1) any AEs, any serious AEs (SAEs), and any severe AEs; (2) serious organ specific adverse events; (3) adverse events of special interest (AESIs). RESULTS: Of the 1,621 studies identified, nine RCTs involving 7,974 patients were eligible for the meta-analysis. There were no significant differences between the experimental and control groups in terms of the incident of AEs: AEs (RR = 0.99, 95% CI: 0.97-1.02, P = 0.68), SAEs (RR = 0.91, 95% CI: 0.81-1.02, P = 0.09), and severe AEs (RR = 0.92, 95% CI: 0.75-1.14, P = 0.46). The pooled data also showed that there was no significant correlation between five types of SAEs grouped by organ class and the IV belimumab (10 mg/kg) intervention, except for 'infections and infestations' (RR = 0.82, 95% CI: 0.70-0.97, P = 0.02) and 'musculoskeletal and connective tissue disorders' (RR = 0.46, 95% CI: 0.32-0.67, P < 0.0001). In addition, we found no significant association between AESIs and the IV administration of belimumab (10 mg/kg) (all malignancies: RR = 1.53, 95% CI: 0.69-3.36, P = 0.3; all post-infusion systemic reactions: RR = 1.05, 95% CI: 0.85-1.30, P = 0.63; depression: RR = 1.42, 95% CI: 0.92-2.20, P = 0.11; serious depression: RR = 2.60, 95% CI: 0.85-7.93, P = 0.09; suicide or self-injury: RR = 0.97, 95% CI: 0.48-1.96, P = 0.92; serious suicide or self-injury: RR = 1.26, 95% CI: 0.59-2.70, P = 0.56). CONCLUSIONS: According to the results of the meta-analysis, SLE patients did not have significantly increased risk of experiencing any type of AEs when receiving SoC therapy. Special caution should be exercised during close follow-ups and individual clinical management before drug prescription.


Assuntos
Lúpus Eritematoso Sistêmico , Padrão de Cuidado , Anticorpos Monoclonais Humanizados/efeitos adversos , Humanos , Imunoterapia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
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