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1.
Mol Psychiatry ; 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-34997190

RESUMO

Acetylcholine (ACh) levels are elevated in actively depressed subjects. Conversely, antagonism of either nicotinic or muscarinic ACh receptors can have antidepressant effects in humans and decrease stress-relevant behaviors in rodents. Consistent with a role for ACh in mediating maladaptive responses to stress, brain ACh levels increase in response to stressful challenges, whereas systemically blocking acetylcholinesterase (AChE, the primary ACh degradative enzyme) elicits depression-like symptoms in human subjects, and selectively blocking AChE in the hippocampus increases relevant behaviors in rodents. We used an ACh sensor to characterize stress-evoked ACh release, then used chemogenetic, optogenetic and pharmacological approaches to determine whether cholinergic inputs from the medial septum/diagonal bands of Broca (MSDBB) or ChAT-positive neurons intrinsic to the hippocampus mediate stress-relevant behaviors in mice. Chemogenetic inhibition or activation of MSDBB cholinergic neurons did not result in significant behavioral effects, while inhibition attenuated the behavioral effects of physostigmine. In contrast, optogenetic stimulation of septohippocampal terminals or selective chemogenetic activation of ChAT-positive inputs to hippocampus increased stress-related behaviors. Finally, stimulation of sparse ChAT-positive hippocampal neurons increased stress-related behaviors in one ChAT-Cre line, which were attenuated by local infusion of cholinergic antagonists. These studies suggest that ACh signaling results in maladaptive behavioral responses to stress if the balance of signaling is shifted toward increased hippocampal engagement.

3.
Sci Total Environ ; 804: 150217, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34520910

RESUMO

Co-pyrolysis technology of urban solid waste and biomass has broad application prospects in alleviating energy crisis and environmental pollution. In this study, thermogravimetric-Fourier transform infrared spectroscopy (TG-FTIR) was used to study the co-pyrolysis characteristics of coal gangue (CG) and coffee industry residue (CIR). CG and CIR were uniformly mixed according to the mass ratios of 1: 0, 7:3, 5:5, 3:7, and 0:1. Then the samples were heated and pyrolyzed in an atmosphere with a nitrogen flow rate of 60 mL/min. As the proportion of CG increased, the comprehensive pyrolysis index (CPI) showed an exponential decrease. FTIR detected that the gas produced by pyrolysis of CG-CIR contained hydroxyl compounds, hydrocarbons, CO2, CO, Phenols, and NH3. CG-CIR co-pyrolysis had obvious interaction. By using Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods, the relationship between activation energy (Eα) and kinetic parameters and conversion degree was studied. Principal component analysis (PCA) was used to determine the principal reaction of CG-CIR pyrolysis. ANN 21 was the best model for predicting the pyrolysis of CG-CIR.


Assuntos
Carvão Mineral , Pirólise , Biomassa , Carvão Mineral/análise , Café , Cinética , Idioma , Termodinâmica , Termogravimetria
4.
Am J Pathol ; 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34756873

RESUMO

The proinflammatory cytokine tumor necrosis factor-α (TNF-α) augments intracellular Ca2+ signaling and contractile responses of airway smooth muscles, leading to airway hyperresponsiveness. However, the underlying mechanism has not been fully elucidated. This study aimed to investigate the cellular mechanism of the potentiated contraction of mouse tracheal smooth muscle induced by TNF-α. The results showed that TNF-α triggered facilitation of mouse tracheal smooth muscle contraction in an epithelium-independent manner. The TNF-α-induced hypercontractility could be suppressed by the protein kinase C inhibitor GF109203X, the tyrosine kinase inhibitor genistein, the Src inhibitor PP2, or the L-type voltage-dependent Ca2+ channel blocker nifedipine. After TNF-α incubation, the α1C L-type Ca2+ channel (CaV1.2) was up-regulated in primary cultured mouse tracheal smooth muscle cells. Pronounced phosphotyrosine levels also were observed in mouse tracheas. In conclusion, this study showed that TNF-α enhanced airway smooth muscle contraction via protein kinase C-Src-CaV1.2 pathways, which provides novel insights into the pathologic role of proinflammatory cytokines in mediating airway hyperresponsiveness.

5.
Microbiome ; 9(1): 192, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34548111

RESUMO

BACKGROUND: Flavonoids are important plant secondary metabolites (PSMs) that have been widely used for their health-promoting effects. However, little is known about overall flavonoid metabolism and the interactive effects between flavonoids and the gut microbiota. The flavonoid-rich bamboo and the giant panda provide an ideal system to bridge this gap. RESULTS: Here, integrating metabolomic and metagenomic approaches, and in vitro culture experiment, we identified 97 flavonoids in bamboo and most of them have not been identified previously; the utilization of more than 70% flavonoid monomers was attributed to gut microbiota; the variation of flavonoid in bamboo leaves and shoots shaped the seasonal microbial fluctuation. The greater the flavonoid content in the diet was, the lower microbial diversity and virulence factor, but the more cellulose-degrading species. CONCLUSIONS: Our study shows an unprecedented landscape of beneficial PSMs in a non-model mammal and reveals that PSMs remodel the gut microbiota conferring host adaptation to diet transition in an ecological context, providing a novel insight into host-microbe interaction. Video abstract.


Assuntos
Microbioma Gastrointestinal , Ursidae , Animais , Dieta , Microbioma Gastrointestinal/genética , Metagenoma , Metagenômica
6.
Sci Total Environ ; 798: 149290, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340093

RESUMO

The pyrolysis experiment of biomass added to coal gangue was studied by thermogravimetric-Fourier transform infrared spectroscopy-mass spectrometry (TG-FTIR-MS) method. The multi-component reaction model was used to simulate the pyrolysis reaction of coal gangue and biomass. The most suitable model was obtained, and the pyrolysis mechanism was analyzed. According to the two-component reaction model of CG pyrolysis, the decomposition temperature range of components in CG is 340-800 °C and 400-620 °C. The five-component reaction model can well simulate the pyrolysis process of coal gangue and biomass. Meanwhile, the effects of different proportions of biomass in the mixture on the gas products of coal gangue pyrolysis were analyzed. It was found that the addition of biomass to coal gangue could promote the release of gaseous organic matter during pyrolysis. CG75PS25 only has a synergistic effect in the high temperature zone greater than 600 °C. CG25PS75 only has a synergistic effect in a small range of 230-300 °C, and there is an inhibitory effect in other temperature ranges. In general, there is an inhibitory effect between coal gangue and biomass on CO2 formation, which is of positive significance for greenhouse gas emission reduction.


Assuntos
Carvão Mineral , Pirólise , Biomassa , Carvão Mineral/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
7.
Bioengineered ; 12(1): 2750-2762, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34130591

RESUMO

Identifying biomarkers for hepatocellular carcinoma (HCC) survival is of great importance for the early detection, monitoring, and predicting for prognosis. This study aimed to investigate the candidate biomarkers for predicting overall survival (OS) in HCC patients. Using RTCGAToolbox, top 50 upregulated differential expressed genes (DEGs) were identified. The least absolute shrinkage and selection operator (LASSO) and Cox models were used to select powerful candidate genes, and log rank method was used to address the survivor functions of potential biomarkers. Selected by LASSO model, ANLN, TTK, AIM1L and person neoplasm cancer status might be candidate parameters associated with OS in HCC patients. After adjusting person neoplasm cancer status, ANLN and TTK levels in Cox model, AIM1L was identified as a risk factor for predicting OS in HCC patients (HR = 1.5, P = 0.037). Validated in The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC) and Gene Expression Omnibus (GEO) series, AIM1L was significantly overexpressed in tumor tissues compared to nontumor tissues (all P < 0.0001). HCC patients with high AIM1L in tumor tissues had significantly unfavorable OS compared to those with low AIM1L in TCGA, ICGC, Gene Expression Profiling Interactive Analysis (GEPIA) and Kaplan-Meier Plotter datasets (all P < 0.05). Conclusively, AIM1L is upregulated in tumor samples and serves as a novel candidate for predicting unfavorable OS in HCC patients.

8.
PLoS Negl Trop Dis ; 15(4): e0009319, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33861752

RESUMO

Trichomonas vaginalis is a common protozoan parasite, which causes trichomoniasis associated with severe adverse reproductive outcomes. However, the underlying pathogenesis has not been fully understood. As the first line of defense against invading pathogens, the vaginal epithelial cells are highly responsive to environmental stimuli and contribute to the formation of the optimal luminal fluid microenvironment. The cystic fibrosis transmembrane conductance regulator (CFTR), an anion channel widely distributed at the apical membrane of epithelial cells, plays a crucial role in mediating the secretion of Cl- and HCO3-. In this study, we investigated the effect of T. vaginalis on vaginal epithelial ion transport elicited by prostaglandin E2 (PGE2), a major prostaglandin in the semen. Luminal administration of PGE2 triggered a remarkable and sustained increase of short-circuit current (ISC) in rat vaginal epithelium, which was mainly due to Cl- and HCO3- secretion mediated by the cAMP-activated CFTR. However, T. vaginalis infection significantly abrogated the ISC response evoked by PGE2, indicating impaired transepithelial anion transport via CFTR. Using a primary cell culture system of rat vaginal epithelium and a human vaginal epithelial cell line, we demonstrated that the expression of CFTR was significantly down-regulated after T. vaginalis infection. In addition, defective Cl- transport function of CFTR was observed in T. vaginalis-infected cells by measuring intracellular Cl- signals. Conclusively, T. vaginalis restrained exogenous PGE2-induced anion secretion through down-regulation of CFTR in vaginal epithelium. These results provide novel insights into the intervention of reproductive complications associated with T. vaginalis infection such as infertility and disequilibrium in vaginal fluid microenvironment.


Assuntos
Ânions/metabolismo , Cloretos/metabolismo , Vaginite por Trichomonas/tratamento farmacológico , Vagina/patologia , Animais , Ânions/farmacologia , Transporte Biológico , Linhagem Celular , Células Cultivadas , Antiportadores de Cloreto-Bicarbonato/fisiologia , AMP Cíclico/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Dinoprostona/metabolismo , Células Epiteliais/efeitos dos fármacos , Epitélio/metabolismo , Epitélio/parasitologia , Epitélio/patologia , Feminino , Humanos , Ratos , Ratos Sprague-Dawley , Vaginite por Trichomonas/parasitologia , Trichomonas vaginalis/metabolismo , Vagina/metabolismo , Vagina/parasitologia
10.
Ann Transl Med ; 9(4): 313, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33708940

RESUMO

Background: Previous studies have suggested the involvement of epithelium in modulating the contractility of neighboring smooth muscle cells. However, the mechanism underlying epithelium-derived relaxation in airways remains largely unclear. This study aimed to investigate the mechanism underlying epithelium-dependent smooth muscle relaxation mediated by neurotransmitters. Methods: The contractile tension of Sprague-Dawley (SD) rat tracheal rings were measured using a mechanical recording system. Intracellular Ca2+ level was measured using a Ca2+ fluorescent probe Fluo-3 AM, and the fluorescence signal was recorded by a laser scanning confocal imaging system. The prostaglandin E2 (PGE2) content was measured using an enzyme-linked immunosorbent assay kit. Results: We observed that the neurotransmitter acetylcholine (ACh) restrained the electric field stimulation (EFS)-induced contraction in the intact but not epithelium-denuded rat tracheal rings. After inhibiting the muscarinic ACh receptor (mAChR) or cyclooxygenase (COX), a critical enzyme in prostaglandin synthesis, the relaxant effect of ACh was attenuated. Exogenous PGE2 showed a similar inhibitory effect on the EFS-evoked contraction of tracheal rings. Moreover, ACh triggered phospholipase C (PLC)-coupled Ca2+ release from intracellular Ca2+ stores and stimulated COX-dependent PGE2 production in primary cultured rat tracheal epithelial cells. Conclusions: Collectively, this study demonstrated that ACh induced rat tracheal smooth muscle relaxation by promoting PGE2 release from tracheal epithelium, which might provide valuable insights into the cross-talk among neurons, epithelial cells and neighboring smooth muscle cells in airways.

12.
Mol Cell Endocrinol ; 526: 111219, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33610642

RESUMO

Prostaglandin E2 (PGE2) is a principal lipid mediator mediating various biological processes including immune responses and fluid secretion. As the first line of host defense against infection, vaginal epithelium plays orchestrated roles in vaginal innate immunity. However, the effect of PGE2 triggered by pro-inflammatory stimuli on vaginal epithelium remains elusive. This study aimed to investigate the regulatory role of PGE2 on vaginal epithelium after lipopolysaccharide (LPS) stimulation. RT-PCR and western blot analysis revealed that E-prostanoid (EP) receptors EP2 and EP4 were expressed in rat vagina. Basolateral application of PGE2 induced anion secretion mediated by cystic fibrosis transmembrane conductance regulator (CFTR) via EP-adenylate cyclase-cAMP signaling pathway in rat vaginal epithelial cells. The in vivo study showed that PGE2 promoted fluid secretion in rat vagina. Moreover, LPS stimulation facilitated cyclooxygenase-dependent PGE2 synthesis and vaginal fluid secretion in vivo. Conclusively, LPS stimulation triggered epithelium-derived PGE2 production in vaginal epithelium, leading to CFTR-mediated anion secretion and luminal flushing. This study provides valuable insights into the physiological role of PGE2 during vaginal bacterial infection.


Assuntos
Líquidos Corporais/metabolismo , Dinoprostona/farmacologia , Epitélio/metabolismo , Lipopolissacarídeos/farmacologia , Vagina/metabolismo , Animais , Ânions , Líquidos Corporais/efeitos dos fármacos , AMP Cíclico/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Feminino , Modelos Biológicos , Ratos Sprague-Dawley , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Vagina/efeitos dos fármacos
13.
ISME J ; 15(7): 2070-2080, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33568789

RESUMO

Mammalian chemosignals-or scent marks-are characterized by astounding chemical diversity, reflecting both complex biochemical pathways that produce them and rich information exchange with conspecifics. The microbiome of scent glands was thought to play prominent role in the chemical signal synthesis, with diverse microbiota metabolizing glandular products to produce odorants that may be used as chemosignals. Here, we use gas chromatography-mass spectrometry and metagenomic shotgun sequencing to explore this phenomenon in the anogenital gland secretions (AGS) of the giant panda (Ailuropoda melanoleuca). We find that this gland contains a diverse community of fermentative bacteria with enzymes that support metabolic pathways (e.g., lipid degradation) for the productions of volatile odorants specialized for chemical communication. We found quantitative and qualitative differences in the microbiota between AGS and digestive tract, a finding which was mirrored by differences among chemical compounds that could be used for olfactory communication. Volatile chemical compounds were more diverse and abundant in AGS than fecal samples, and our evidence suggests that metabolic pathways have been specialized for the synthesis of chemosignals for communication. The panda's microbiome is rich with genes coding for enzymes that participate in the fermentation pathways producing chemical compounds commonly deployed in mammalian chemosignals. These findings illuminate the poorly understood phenomena involved in the role of symbiotic bacteria in the production of chemosignals.


Assuntos
Glândulas Odoríferas , Ursidae , Animais , Bactérias/genética , Odorantes , Feromônios
14.
J Neurophysiol ; 125(1): 23-42, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33085562

RESUMO

Dendritic spikes in thin dendritic branches (basal and oblique dendrites) are traditionally inferred from spikelets measured in the cell body. Here, we used laser-spot voltage-sensitive dye imaging in cortical pyramidal neurons (rat brain slices) to investigate the voltage waveforms of dendritic potentials occurring in response to spatially restricted glutamatergic inputs. Local dendritic potentials lasted 200-500 ms and propagated to the cell body, where they caused sustained 10- to 20-mV depolarizations. Plateau potentials propagating from dendrite to soma and action potentials propagating from soma to dendrite created complex voltage waveforms in the middle of the thin basal dendrite, comprised of local sodium spikelets, local plateau potentials, and backpropagating action potentials, superimposed on each other. Our model replicated these voltage waveforms across a gradient of glutamatergic stimulation intensities. The model then predicted that somatic input resistance (Rin) and membrane time constant (tau) may be reduced during dendritic plateau potential. We then tested these model predictions in real neurons and found that the model correctly predicted the direction of Rin and tau change but not the magnitude. In summary, dendritic plateau potentials occurring in basal and oblique branches put pyramidal neurons into an activated neuronal state ("prepared state"), characterized by depolarized membrane potential and smaller but faster membrane responses. The prepared state provides a time window of 200-500 ms, during which cortical neurons are particularly excitable and capable of following afferent inputs. At the network level, this predicts that sets of cells with simultaneous plateaus would provide cellular substrate for the formation of functional neuronal ensembles.NEW & NOTEWORTHY In cortical pyramidal neurons, we recorded glutamate-mediated dendritic plateau potentials with voltage imaging and created a computer model that recreated experimental measures from dendrite and cell body. Our model made new predictions, which were then tested in experiments. Plateau potentials profoundly change neuronal state: a plateau potential triggered in one basal dendrite depolarizes the soma and shortens membrane time constant, making the cell more susceptible to firing triggered by other afferent inputs.


Assuntos
Potenciais de Ação , Dendritos/fisiologia , Modelos Neurológicos , Células Piramidais/fisiologia , Animais , Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Dendritos/metabolismo , Feminino , Ácido Glutâmico/metabolismo , Masculino , Células Piramidais/metabolismo , Ratos , Ratos Sprague-Dawley , Potenciais Sinápticos
15.
Proc Natl Acad Sci U S A ; 117(51): 32493-32498, 2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33288697

RESUMO

Attraction to feces in wild mammalian species is extremely rare. Here we introduce the horse manure rolling (HMR) behavior of wild giant pandas (Ailuropoda melanoleuca). Pandas not only frequently sniffed and wallowed in fresh horse manure, but also actively rubbed the fecal matter all over their bodies. The frequency of HMR events was highly correlated with an ambient temperature lower than 15 °C. BCP/BCPO (beta-caryophyllene/caryophyllene oxide) in fresh horse manure was found to drive HMR behavior and attenuated the cold sensitivity of mice by directly targeting and inhibiting transient receptor potential melastatin 8 (TRPM8), an archetypical cold-activated ion channel of mammals. Therefore, horse manure containing BCP/BCPO likely bestows the wild giant pandas with cold tolerance at low ambient temperatures. Together, our study described an unusual behavior, identified BCP/BCPO as chemical inhibitors of TRPM8 ion channel, and provided a plausible chemistry-auxiliary mechanism, in which animals might actively seek and utilize potential chemical resources from their habitat for temperature acclimatization.


Assuntos
Comportamento Animal , Esterco , Canais de Cátion TRPM/genética , Ursidae , Animais , Feminino , Células HEK293 , Cavalos , Humanos , Masculino , Esterco/análise , Camundongos Endogâmicos C57BL , Filogenia , Sesquiterpenos Policíclicos/análise , Sesquiterpenos Policíclicos/farmacologia , Pirimidinonas/farmacologia , Ratos Wistar , Canais de Cátion TRPM/metabolismo , Temperatura
16.
Conserv Physiol ; 8(1): coaa085, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014375

RESUMO

Many factors, including the inner status of the individuals and external environment, can influence the parasite infections and stress physiology in mammals. Here, we explored the influence of the sex, age, reproductive season and seasonal food availability on the parasitism and stress physiology in wild giant pandas (Ailuropoda melanoleuca) through nutrient and steroid hormone analysis and parasitic infection measurement. Diet composition had significant influences on the faecal cortisol levels and parasite load of wild giant pandas. The seasonal dynamic of the cortisol levels and parasite load in faeces co-vary with the seasonal nutrient intake levels of the pandas, which concurrently arrived the peaks at the wood bamboo shoot-eating period in May (parasite infection intensity, 41.47 ± 12.11 eggs/g of wet faeces; cortisol levels, 619.34 ± 70.55 ng/g dry faeces) that the nutrition intake by wild pandas was the highest (protein/fibre, 69.23 ± 9.93). Meanwhile, age class is also as an important factor to affect the parasite load and stress physiology of wild giant pandas. Cubs and sub-adults suffered more helminth burden and stress physiology than adults and old individuals. This is the first study to evaluate the inner and external factors influence on parasitism and stress physiology in wild giant pandas. The findings facilitate a better understanding of how environmental factors might influence the physiology, behaviour and health of pandas and other species and have implications for the conservation and management of the endangered species.

17.
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
18.
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
19.
Zool Res ; 41(3): 273-280, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32279465

RESUMO

Interspecific killing is a primary reason for the low survival rates of some animal species. The giant panda ( Ailuropoda melanoleuca) is an altricial eutherian mammal and thus, in comparison to other infants, panda cubs are highly vulnerable, which may significantly influence the selection of breeding sites by females. Here, we used infrared camera traps to monitor giant panda dens for 5.5 years in Foping National Nature Reserve (FNNR) to determine how interspecific factors affect den selection by wild female pandas. Results indicated that Asian black bears ( Ursus thibetanus), yellow-throated martens ( Martes flavigula), leopard cats ( Prionailurus bengalensis), and masked palm civets ( Paguma larvata) visited the dens frequently, and the presence of these species negatively influenced den selection by female pandas. Interestingly, the presence of rodents and terrestrial birds appeared to indicate den safety, and female giant pandas were not averse and even preferred dens with a high abundance index of rodents and terrestrial birds. The den suitability index (DSI) was a reliable tool for evaluating whether dens were suitable for female giant pandas to give birth to and rear cubs, with preference for dens with high DSI values. This study increases our understanding of the den selection criteria of female giant pandas and the main threats to the survival of their cubs, thus providing important guidance for the conservation and management of this species.


Assuntos
Comportamento Animal , Ursidae/fisiologia , Animais , Animais Selvagens , Carnívoros/fisiologia , China , Conservação dos Recursos Naturais , Ecossistema , Feminino , Reprodução
20.
J Med Food ; 22(9): 963-970, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31259654

RESUMO

Naringin and its aglycone, naringenin, occur naturally in our regular diet and traditional Chinese medicines. This study aimed to detect an effective therapeutic approach for cough variant asthma (CVA) through evaluating the relaxant effect of these two bioactive herbal monomers as antitussive and antiasthmatic on rat tracheal smooth muscle. The relaxant effect was determined by measuring muscular tension with a mechanical recording system in rat tracheal rings. Cytosolic Ca2+ concentration was measured using a confocal imaging system in primary cultured tracheal smooth muscle cells. In rat tracheal rings, addition of both naringin and naringenin could concentration dependently relax carbachol (CCh)-evoked tonic contraction. This epithelium-independent relaxation could be suppressed by BaCl2, tetraethylammonium, and iberiotoxin (IbTX), but not by glibenclamide. After stimulating primary cultured tracheal smooth muscle cells by CCh or high KCl, the intracellular Ca2+ increase could be inhibited by both naringin and naringenin, respectively. This reaction was also suppressed by IbTX. These results demonstrate that both naringin and naringenin can relax tracheal smooth muscle through opening big conductance Ca2+-activated K+ channel, which mediates plasma membrane hyperpolarization and reduces Ca2+ influx. Our data indicate a potentially effective therapeutic approach of naringin and naringenin for CVA.


Assuntos
Antiasmáticos/administração & dosagem , Antitussígenos/administração & dosagem , Asma/tratamento farmacológico , Flavanonas/administração & dosagem , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Extratos Vegetais/administração & dosagem , Traqueia/efeitos dos fármacos , Animais , Asma/genética , Asma/metabolismo , Asma/fisiopatologia , Cálcio/metabolismo , Citrus/química , Humanos , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/genética , Masculino , Relaxamento Muscular/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Traqueia/fisiopatologia
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