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An unfavorable lifestyle disrupts the circadian rhythm, leading to metabolic dysfunction in adult humans and animals. Increasing evidence suggests that night-restricted feeding (NRF) can effectively prevent ectopic fat deposition caused by circadian rhythm disruption, and reduce the risk of metabolic diseases. However, previous studies have mainly focused on the prevention of obesity in adults by regulating dietary patterns, whereas limited attention has been paid to the effect of NRF on metabolism during growth and development. Here, we used weaning rabbits as models and found that NRF increased body weight gain without increasing feed intake, and promoted insulin-mediated protein synthesis through the mTOR/S6K pathway and muscle formation by upregulating MYOG. NRF improved the circadian clock, promoted PDH-regulated glycolysis and CPT1B-regulated fatty-acid ß-oxidation, and reduced fat content in the serum and muscles. In addition, NRF-induced body temperature oscillation might be partly responsible for the improvement in the circadian clock and insulin sensitivity. Time-restricted feeding could be used as a nondrug intervention to prevent obesity and accelerate growth in adolescents.
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Relógios Circadianos , Ritmo Circadiano , Ingestão de Alimentos , Comportamento Alimentar , Obesidade , Animais , Masculino , Obesidade/metabolismo , Obesidade/patologia , Obesidade/prevenção & controle , CoelhosRESUMO
In this study, an efficient screening method based on a modified quick, easy, cheap, effective, rugged, and safe extraction method combined with ultra-high-performance liquid chromatography coupled to tandem quadrupole time-of-flight mass spectrometry was established for the determination of 90 pesticides residues in Panax Ginseng. The accuracy of the method was then verified by analyzing the false positive rate and the screening detection limit in Ginseng. The results revealed that the screening detection limit of 33 of 90 pesticide residues were 0.01 mg·kg-1 , 22 species were 0.05 mg·kg-1 , 11 species were 0.10 mg·kg-1 , 8 species were 0.20 mg·kg-1 , and another 16 species were greater than 0.20 mg·kg-1 . A total of 73 pesticides were ultimately suitable to be practically applied for rapid analysis of pesticide residues in Ginseng. Finally, the established method was used to analyze the pesticide residues in 35 Ginseng samples available on the market. And the residual of dimethomorph, azoxystrobin, tebuconazole, and pyraclostrobin was relatively severe in Ginseng samples. This work expanded the range of pesticides detected and provided a rapid, effective method for pesticides screening in Ginseng.
Assuntos
Panax , Resíduos de Praguicidas , Praguicidas , Cromatografia Líquida de Alta Pressão/métodos , Panax/química , Resíduos de Praguicidas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem/métodosRESUMO
BACKGROUND: Progressive axon degeneration is a common pathological feature of neurodegenerative diseases. Cdc42 is a member of the Rho GTPase family that participates in axonogenesis. GSK-3ß is a serine/threonine kinase highly implicated in neuronal development and neurodegeneration. This study aimed to examine whether cdc42 promotes axonogenesis by regulating GSK-3ß activity. METHODS: Hippocampal neurons were isolated from neonatal Sprague-Dawley rats and transfected with designated plasmid vectors to alter the activities of cdc42 and GSK-3ß. LiCl treatment was used to inhibit the GSK-3ß activity in primary neurons. GSK-3ß activity was determined by an enzyme activity assay kit. Immunofluorescence staining was used to detect axons stained with anti-Tau-1 antibody and dendrites stained with anti-MAP2 antibody. RESULTS: Transfection with an active cdc42 mutant (cdc42F28L) decreased the activity of GSK-3ß and induced axonogenesis in primary rat hippocampal neurons, while transfection with a negative cdc42 mutant (cdc42N17) resulted an opposite effect. Moreover, transfection with plasmid vectors carrying wild-type GSK-3ß or a constitutively active GSK3ß mutant (GSK-3ß S9A) increased the activity of GSK-3ß and attenuated axonogenesis of primary hippocampal neurons with excessive cdc42 activity, whereas inhibition of GSK-3ß by LiCl abolished the inhibitory effect of the negative cdc42 mutant on axonogenesis. CONCLUSIONS: This study suggests that cdc42 induces axonogenesis of primary rat hippocampal neurons via inhibiting GSK-3ß activity. These findings support further investigation into the mechanisms of cdc42/GSK-3ß-mediated axonogenesis.
Assuntos
Hipocampo , Neurônios , Proteína cdc42 de Ligação ao GTP , Animais , Glicogênio Sintase Quinase 3 beta , Hipocampo/citologia , Neurônios/fisiologia , Fosforilação , Proteínas Serina-Treonina Quinases , Ratos , Ratos Sprague-Dawley , Serina/farmacologia , Proteína cdc42 de Ligação ao GTP/fisiologiaRESUMO
The establishment of polarity is an essential process in early neuronal development. Cdc42, a GTPase of the Rho family, is a key regulator of cytoskeletal dynamics and neuronal polarity. However, the mechanisms underlying the action of cdc42 in regulating axonogenesis have not been elucidated. Here, we expressed wild-type cdc42, a constitutively active cdc42 mutant (cdc42F28L) and a dominant negative cdc42 mutant (cdc42N17), respectively, in the primary hippocampal neurons to alter the activity of cdc42. We found that cdc42 activities were paralleled with the capacities to promote axonogenesis in the cultured neurons. Cdc42 also enhanced microtubule stability in the cultured neurons. Pharmacologically stabilizing microtubules significantly abrogated the defective axonogenesis induced by cdc42 inhibition. Moreover, cdc42 promoted the dephosphorylation of collapsing response mediator protein-2 (CRMP-2) at Thr514 by increasing GSK-3ß phosphorylation at Ser9 in the cultured neurons. These findings suggest that cdc42 may facilitate axonogenesis by promoting microtubule stabilization in rat primary hippocampal neurons.
Assuntos
Axônios/metabolismo , Hipocampo/metabolismo , Microtúbulos/metabolismo , Neurônios/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Animais , Axônios/patologia , Polaridade Celular/fisiologia , Células Cultivadas , Dendritos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurogênese/fisiologia , Fosforilação/fisiologia , Ratos Sprague-DawleyRESUMO
The vertebrate heart tube originates from cardiogenic mesodermal cells in the early embryo, and subsequently elongates by progressive addition of second heart field (SHF) progenitor cells from adjacent pharyngeal mesoderm and splanchnic mesoderm. Insufficient addition of SHF cells to the heart tube causes the failure of maximal elongation of the heart tube, which results in a series of developmental defects including the most common congenital birth defects, such as right ventricular dysplasia and outflow tract septation, and alignment anomalies. SHF cells form an atypical, apicobasally polarized epithelium which is characterized by apical monocilia, and dynamic actin-rich basal filopodia. In this review, we summarize recent research progresses of actin cytoskeleton in the deployment process of mouse SHF progenitor cells, and reveal the significance of actin cytoskeleton in SHF development, especially in the deployment of SHF cells to the outflow tract, to provide theoretical reference for elucidating and understanding the biological characteristics of SHF deployment.
Assuntos
Citoesqueleto de Actina/fisiologia , Coração/embriologia , Mesoderma/citologia , Miocárdio/citologia , Células-Tronco/citologia , Animais , Camundongos , OrganogêneseRESUMO
A stable mouse model of hyperuricemia was established by intraperitoneal injection of xanthine and oxonate, comparing the water extracts (containing crude drug 360 mg · mL(-1)) of Ermiao pill categorized formula (The ratio of atractylodes lancea to cortex phellodendri was 1:1, 1:2 and 2:1, respectively) and Ermiao pill (360 mg · mL(-1)) administered to different groups of animals continuously for two weeks and assessing the protection or treatment of drug on hyperuricemia. The xanthine oxidase (XOD) activities in serum and liver were detected by ultraviolet-visible spectroscopy at 570 nm wavelength, The results showed that as compared with each group, the XOD activity of the model group was significantly increased in serum (p < 0.01), XOD activity showed no significant difference in liver (p > 0.05), but compared with the model group, the XOD activity of each treatment group was significantly lower in serum and liver (p < 0.01), especially for the group treated with Ermiao pill categorized formula with the ratio of Atractylodes lancea to Cortex Phellodendri being 1:2. The morphological changes of glomerular and tubular interstitial fibrosis were measured by Hematoxylin-eosin staining (HE staining) and Masson trichrome staining (Masson staining)for kidney paraffin sections. The results showed that the glomerular atrophy, vascular loops confusion, a certain degree of inflammatory cell infiltration, interstitial fibrosis and other phenomena appeared in the model group. Compared to model group, these pathological phenomena of the treatment groups were significantly improved. The area showed that compared with each group, the fibrosis of the model group was significantly increased (p < 0.01 or p < 0.05), but compared with Ermiao pill categorized formula, the differences for the group of Ermiao pill was lower (p < 0.01), especially for the group treated with Ermiao pill categorized formula with the ratio of Atractylodes lancea to Cortex Phellodendri being 1 : 2. In this experiment, the damage of kidney and XOD activity serve as the index to evaluate the protection or treatment of drug on hyperuricemia, providing a scientific basis for the development of Ermiao pill categorized formula.
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Medicamentos de Ervas Chinesas/uso terapêutico , Hiperuricemia/tratamento farmacológico , Animais , Modelos Animais de Doenças , Rim/patologia , Fígado/enzimologia , Camundongos , Ratos , Xantina Oxidase/sangue , Xantina Oxidase/metabolismoRESUMO
AIM: Daidzein (4',7-dihydroxyisoflavone) is an isoflavone exiting in many herbs that has shown anti-inflammation activity. The aim of this study was to investigate the mechanism underlying its anti-inflammatory action in murine lung epithelial cells. METHODS: C57BL/6 mice were intranasally exposed to TNF-α to induce lung inflammation. The mice were injected with daidzein (400 mg/kg, ip) before TNF-α challenge, and sacrificed 12 h after TNF-α challenge, and lung tissues were collected for analyisis. In in vitro studies, murine MLE-12 epithelial cells were treated with TNF-α (20 ng/mL). The expression of pro-inflammatory chemokine Cxcl2 mRNA and NF-κB transcriptional activity were examined using real-time PCR and a dual reporter assay. Protein poly-adenosine diphosphate-ribosylation (PARylation) was detecyed using Western blotting and immunoprecipitation assays. RESULTS: Pretreatment of the mice with daidzein markedly attenuated TNF-α-induced lung inflammation, and inhibited Cxcl2 expression in lung tissues. Furthermore, daidzein (10 µmol/L) prevented TNF-α-induced increases in Cxcl2 expression and activity and NF-κB transcriptional activity, and markedly inhibited TNF-α-induced protein PARylation in MLE-12 cells in vitro. In MLE-12 cells co-transfected with the PARP-1 expression plasmid and NF-κB-luc (or Cxcl2-luc) reporter plasmid, TNF-α markedly increased NF-κB (or Cxcl2) activation, which were significantly attenuated in the presence of daidzein (or the protein PARylation inhibitor PJ 34). PARP-1 activity assay showed that daidzein (10 µmol/L) reduced the activity of PARP-1 by â¼75%. CONCLUSION: The anti-inflammatory action of daidzein in murine lung epithelial cells seems to be mediated via a direct interaction with PARP-1, which inhibits RelA/p65 protein PARylation required for the transcriptional modulation of pro-inflammatory chemokines such as Cxcl2.
Assuntos
Anti-Inflamatórios/farmacologia , Quimiocina CXCL2/metabolismo , Células Epiteliais/efeitos dos fármacos , Isoflavonas/farmacologia , Pulmão/efeitos dos fármacos , Pneumonia/prevenção & controle , Poli(ADP-Ribose) Polimerases/metabolismo , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa , Animais , Linhagem Celular , Quimiocina CXCL2/genética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Genes Reporter , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Pneumonia/induzido quimicamente , Pneumonia/imunologia , Pneumonia/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , TransfecçãoRESUMO
This study aims to observe the protective effects of ginsenoside Rb1 on liver and lung in rats with septic shock and reveal its mechanism. Rats were randomly divided into three groups: sham, cecal ligation and puncture (CLP), and CLP with ginsenoside Rb1. Then, the survival rate, arterial blood pressure, TLR4 mRNA, and TNF-α levels were determined. The liver and lung tissues were stained with hematoxylin-eosin (HE). The overall survival rate of the Rb1 group was significantly higher than that of the CLP group. Mean arterial blood pressure went down in both the CLP and Rb1 groups after CLP, and there was a significant difference both in the sham and Rb1 groups when compared with the CLP group. The Rb1 treatment group had markedly lower TLR4 mRNA expression and TNF-α levels than the CLP group. In the CLP group, pathology showed swelling, degeneration, necrosis, and neutrophil infiltration in the liver and alveolar epithelial cells. However, in the Rb1 group, there was mild degeneration and slight neutrophil infiltration, but no obvious necrosis. Rb1 may improve the survival rate, ameliorate arterial blood pressure, and protect the liver and lung in septic shock rats by downregulating the expression of TLR4 mRNA and inhibiting the production of TNF-α.
Assuntos
Ginsenosídeos/uso terapêutico , Insuficiência Hepática/prevenção & controle , Lesão Pulmonar/prevenção & controle , Sepse/tratamento farmacológico , Animais , Avaliação Pré-Clínica de Medicamentos , Ginsenosídeos/farmacologia , Insuficiência Hepática/etiologia , Lesão Pulmonar/etiologia , Miocárdio/metabolismo , Panax , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sepse/complicações , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/sangueRESUMO
Seasonal environmental shifts and improper eating habits are the important causes of diarrhea in children and growing animals. Whether adjusting feeding time at varying temperatures can modify cecal bacterial structure and improve diarrhea remains unknown. Three batches growing rabbits with two groups per batch were raised under different feeding regimens (fed at daytime vs. nighttime) in spring, summer and winter separately, and contents were collected at six time points in 1 day and used 16S rRNA sequencing to investigate the effects of feeding regimens and season on the composition and circadian rhythms of cecum bacteria. Randomized forest regression screened 12 genera that were significantly associated with seasonal ambient temperature changes. Nighttime feeding reduced the abundance of the conditionally pathogenic bacteria Desulfovibrio and Alistipes in summer and Campylobacter in winter. And also increases the circadian rhythmic Amplicon Sequence Variants in the cecum, enhancing the rhythm of bacterial metabolic activity. This rhythmic metabolic profile of cecum bacteria may be conducive to the digestion and absorption of nutrients in the host cecum. In addition, this study has identified 9 genera that were affected by the combination of seasons and feeding time. In general, we found that seasons and feeding time and their combinations affect cecum composition and circadian rhythms, and that daytime feeding during summer and winter disrupts the balance of cecum bacteria of growing rabbits, which may adversely affect cecum health and induce diarrhea risk.
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Chronic myeloid leukemia (CML) is a blood cancer characterized by dysregulated production of maturing myeloid cells driven by the product of the Philadelphia chromosome, the BCR-ABL1 tyrosine kinase. Tyrosine kinase inhibitors (TKIs) have proved effective in treating CML, but there is still a cohort of patients who do not respond to TKI therapy even in the absence of mutations in the BCR-ABL1 kinase domain that mediate drug resistance. To discover novel strategies to improve TKI therapy in CML, we developed a nonlinear mathematical model of CML hematopoiesis that incorporates feedback control and lineage branching. Cell-cell interactions were constrained using an automated model selection method together with previous observations and new in vivo data from a chimeric BCR-ABL1 transgenic mouse model of CML. The resulting quantitative model captures the dynamics of normal and CML cells at various stages of the disease and exhibits variable responses to TKI treatment, consistent with those of CML patients. The model predicts that an increase in the proportion of CML stem cells in the bone marrow would decrease the tendency of the disease to respond to TKI therapy, in concordance with clinical data and confirmed experimentally in mice. The model further suggests that, under our assumed similarities between normal and leukemic cells, a key predictor of refractory response to TKI treatment is an increased maximum probability of self-renewal of normal hematopoietic stem cells. We use these insights to develop a clinical prognostic criterion to predict the efficacy of TKI treatment and design strategies to improve treatment response. The model predicts that stimulating the differentiation of leukemic stem cells while applying TKI therapy can significantly improve treatment outcomes.
Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Camundongos , Animais , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Mielopoese , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/farmacologia , Camundongos Transgênicos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genéticaRESUMO
The dry root and rhizome of Panax ginseng C. A. Mey has garnered much interest owing to its medicinal properties against diabetes and cardiovascular diseases. In this study, an ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS)-based metabolomics approach was used to illustrate the therapeutic mechanisms of ginseng extract on the serum and urinary metabolic profiles in streptozotocin-induced type 1 diabetes mellitus (T1DM) rats. Pharmacological and renal parameters in response to the administration of ginseng were also evaluated. In total, 16 serum endogenous metabolites and 14 urine endogenous metabolites, including pyruvic acid, indoleacetic acid, and phenylacetylglycine, were identified as potential biomarkers for diabetes. Pathway enrichment and network analysis revealed that the biomarkers modulated by ginseng were primarily involved in phenylalanine and pyruvate metabolism, as well as in arginine biosynthesis. Moreover, the levels of several renal injury-related biomarkers in T1DM rats were significantly restored following treatment with ginseng. The administration of the extract helped maintain tissue structure integrity and ameliorated renal injury. The findings suggest that the regulatory effect of ginseng extract on T1DM involves metabolic management of diabetic rats, which subsequently attenuates T1DM-induced early renal dysfunction.
Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Panax , Animais , Biomarcadores , Cromatografia Líquida de Alta Pressão/métodos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/tratamento farmacológico , Rim , Metabolômica/métodos , Panax/química , Extratos Vegetais/farmacologia , RatosRESUMO
BACKGROUND: Misuse of disinfectants during the coronavirus disease 2019 pandemic has led to several poisoning incidents. However, there are few clinical case reports on poisoning caused by improper mixing of household disinfectants. AIM: To summarize the clinical characteristics and treatment effects of chlorine poisoning caused by improper mixing of hypochlorite bleach with acidic cleaning agents.METHODSWe retrospectively analyzed baseline and clinical data, clinical symptoms, and treatment methods of seven patients with chlorine poisoning who were admitted to the National Army Poisoning Treatment Center. RESULTS: Among the seven patients, the average poisoning time (exposure to admission) was 57 h (4-240 h). All patients were involved in cleaning bathrooms. Chest computed tomography scans revealed bilateral lung effusions or inflammatory changes in five patients. The partial pressure of oxygen decreased in six patients, and respiratory failure occurred in one. Five patients had different degrees of increase in white blood cell count. Humidified oxygen therapy, non-invasive mechanical ventilation, anti-inflammatory corticosteroids, antioxidants, and antibiotics were administered for treatment. The average length of hospital stay was 7 d (4-9 d). All seven patients recovered and were discharged. CONCLUSION: Improper mixing of household disinfectants may cause damage to the respiratory system due to chlorine poisoning. Corticosteroids may improve lung exudation in severe cases, and symptomatic supportive treatment should be performed early.
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Type 2 diabetes is the most prevalent endocrine disease in the world, and recently the gut microbiota have become a potential target for its management. Recent studies have illustrated that this disease may predispose individuals to certain microbiome compositions, and treatments like metformin have been shown to change gut microbiota and their associated metabolic pathways. However, given the limitations and side effects associated with pharmaceuticals currently being used for therapy of diabetes, there is a significant need for alternative treatments. In this study, we investigated the effects of a root extract from Rhodiola rosea in a Leptin receptor knockout (db/db) mouse model of type 2 diabetes. Our previous work showed that Rhodiola rosea had anti-inflammatory and gut microbiome-modulating properties, while extending lifespan in several animal models. In this study, treatment with Rhodiola rosea improved fasting blood glucose levels, altered the response to exogenous insulin, and decreased circulating lipopolysaccharide and hepatic C-reactive protein transcript levels. We hypothesize that these changes may in part reflect the modulation of the microbiota, resulting in improved gut barrier integrity and decreasing the translocation of inflammatory biomolecules into the bloodstream. These findings indicate that Rhodiola rosea is an attractive candidate for further research in the management of type 2 diabetes.
Assuntos
Diabetes Mellitus Tipo 2 , Microbiota , Rhodiola , Animais , Biomarcadores , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inflamação/tratamento farmacológico , Camundongos , Camundongos Knockout , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Receptores para Leptina/genéticaRESUMO
The haematopoietic system has a highly regulated and complex structure in which cells are organized to successfully create and maintain new blood cells. It is known that feedback regulation is crucial to tightly control this system, but the specific mechanisms by which control is exerted are not completely understood. In this work, we aim to uncover the underlying mechanisms in haematopoiesis by conducting perturbation experiments, where animal subjects are exposed to an external agent in order to observe the system response and evolution. We have developed a novel Bayesian hierarchical framework for optimal design of perturbation experiments and proper analysis of the data collected. We use a deterministic model that accounts for feedback and feedforward regulation on cell division rates and self-renewal probabilities. A significant obstacle is that the experimental data are not longitudinal, rather each data point corresponds to a different animal. We overcome this difficulty by modelling the unobserved cellular levels as latent variables. We then use principles of Bayesian experimental design to optimally distribute time points at which the haematopoietic cells are quantified. We evaluate our approach using synthetic and real experimental data and show that an optimal design can lead to better estimates of model parameters.
Assuntos
Hematopoese , Projetos de Pesquisa , Animais , Teorema de Bayes , Divisão Celular , Modelos BiológicosRESUMO
INTRODUCTION: A decline in semen quality caused by global warming and torrid working conditions is a major cause of human male infertility, and heat stress-induced decreases in male reproductive ability results in economic losses in livestock husbandry. Increasing evidence suggests that melatonin exerts protective effects on stress-induced DNA damage and apoptosis in germ cells. However, few studies have assessed the effects of melatonin on testicular recovery during post-heat stress and the underlying mechanisms. METHODS AND RESULTS: In vivo studies using 8-week-old male CD-1 mice revealed that melatonin pretreatment (50 mg/kg for 5 days) did not alleviate heat stress-induced germ cell loss and disrupted testicular histomorphology, however, long-term melatonin administration after heat stress accelerated germ cell apoptosis, spermatogenic cell regeneration, and testicular weight recovery. In vitro studies demonstrated that melatonin enhanced RAC1 activity, resulting in increased phagocytosis of apoptotic germ cells by Sertoli cells. In addition, melatonin restored gap junctions and tight junctions after heat stress, thereby promoting hollow seminiferous tubule filling. DISCUSSION: Long-term melatonin administration accelerated testicular recovery after heat stress by enhancing the phagocytotic activity of Sertoli cells and the regeneration of spermatogenic cells. This finding suggests that melatonin is a potential therapeutic for heat stress-induced male infertility.
Assuntos
Melatonina , Animais , Apoptose , Resposta ao Choque Térmico , Humanos , Junções Intercelulares , Masculino , Melatonina/farmacologia , Camundongos , Fagocitose , Análise do Sêmen/veterinária , Testículo , Proteínas rac1 de Ligação ao GTPRESUMO
The circadian misalignment of the gut microbiota caused by unusual eating times in adult animals is related to disease development. However, whether the composition and diurnal rhythm of gut microbiota can be optimized by synchronizing the window period of eating with natural eating habits to reduce the risk of diarrhea remains unclear, especially in growing animals. In this study, 108 5-week-old weaned rabbits (nocturnal animals) were randomly subjected to daytime feeding (DF) and night-restricted feeding (NRF). At age 12 weeks, six rabbits were selected from each group, and caecum and cecal contents, as well as serum samples were collected at 4-h intervals during 24 h. Overall, NRF was found to reduce the risk of diarrhea in growing rabbits, improved the diurnal rhythm and abundance of beneficial microorganisms, along with the production of beneficial metabolites, whereas reduced the abundance of potential pathogens (Synergistes, Desulfovibrio, and Alistipes). Moreover, NRF improved diurnal rhythm of tryptophan hydroxylase isoform 1 and serotonin. Furthermore, NRF strengthened the diurnal amplitude of body core temperature, and promoted the diurnal expression of intestinal clock genes (BMAL1, CLOCK, REV-ERBα, and PER1), and genes related to the regulation of the intestinal barrier (CLAUDIN-1), and intestinal epithelial cell self-proliferation and renewal (BMI1). In vitro simulation experiments further revealed that synchronization of microbial-driven serotonin rhythm and eating activity-driven body temperature oscillations, which are important zeitgebers, could promote the diurnal expression of clock genes and CLAUDIN-1 in rabbit intestinal epithelial cells (RIEC), and enhance RIEC proliferation. This is the first study to reveal that NRF reprograms the diurnal rhythm of the gut microbiome, promotes the diurnal expression of clock genes and tight junction genes via synchronization of microbial-driven serotonin rhythm and eating activity-driven body temperature oscillations, thereby improving intestinal health and reducing the risk of diarrhea in growing rabbits. Collectively, these results provide a new perspective for the healthy feeding and management of growing animals.
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Temperatura Corporal , Serotonina , Animais , Ritmo Circadiano , Comportamento Alimentar , CoelhosRESUMO
Abnormally hyperphosphorylated tau is the major protein constituent of neurofibrillary tangles (NFTs) in the brain of Alzheimer disease (AD) patients. Cell cycle reactivation is considered an important neuropathological feature of AD, and re-expression and activation of cell cycle regulators are known to occur in neurons containing NFTs. The aim of the present study was to investigate cell cycle reactivation during tau hyperphosphorylation in primary hippocampal neurons. We used forskolin, a specific activator of PKA, to induce tau hyperphosphorylation in cultured primary hippocampal neurons, and then measured levels of cyclin D1 and cyclin B1. We found that forskolin induced hyperphosphorylation of tau at Ser214, Ser396, and Ser202/Thr205 sites, attaining peak levels at 6, 12, and 12 h, respectively, while returning to normal levels at 24 h. Forskolin also induced a sustained cAMP elevation and PKA activation, which peaked at 6 h, in association with activation and overexpression of protein phosphatase-2A (PP-2A) at 24 h. The tau hyperphosphorylation was accompanied by increases in cyclin D1 and cyclin B1 levels; immunostaining showed overlapping distribution of hyperphosphorylated tau and cyclin D1 and cyclin B1 in primary hippocampal neurons. Forskolin induced hyperphosphorylation of tau and increased cyclin D1 and cyclin B1 protein levels in HEK293/tau441 cells, but not in the HEK293/vector cells, whereas the PKA inhibitor H89 inhibited the effects of forskolin on tau hyperphosphorylation and cyclin D1 and cyclin B1 protein levels. These findings suggest that forskolin induces tau hyperphosphorylation, which is itself necessary for the subsequent increases of cyclin D1 and cyclin B1 levels.
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Ciclo Celular/efeitos dos fármacos , Colforsina/farmacologia , Hipocampo/citologia , Neurônios/citologia , Neurônios/metabolismo , Proteínas tau/metabolismo , Animais , Animais Recém-Nascidos , Células Cultivadas , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ciclina B1/metabolismo , Ciclina D1/metabolismo , Células HEK293 , Humanos , Isoquinolinas/farmacologia , Neurônios/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2/metabolismo , Ratos Sprague-Dawley , Sulfonamidas/farmacologiaRESUMO
A molecular spectroscopic investigation of the interaction of phenacyl thiazolium bromide (PTB) and bovine serum albumin (BSA) or human serum albumin (HSA) is reported employing fluorescence quenching techniques. It is determined that the maximal excitation wavelength is 280 nm for BSA solution, and 290 nm for HAS solution. When PTB was added into these solutions gradually, the emission peaks were decreased obviously, which are typical quenching phenomena. The results obtained reveal that there is a medium-intensity binding affinity for PTB with HSA and BSA. At 15 degrees C, the binding constants of PTB and BSA (HSA) are 3.66 x 10(3) and 3.83 x 10(3), and the numbers of binding sites are 1.02 and 1.06 respectively. At 37 degrees C, the binding constants of PTB and BSA (HSA) are 3.58 x 10(3) and 3.35 x 10(3), and the numbers of binding sites are 0.95 and 0.87 respectively. According to the thermodynamic parameters, the main sort of the binding force between the drug and BSA or HSA was electrostatic force. Based on the Föster non-radiation energy transfer theory, it could be acquired that the distance between BSA or HSA and PTB is 7.5 or 7.9 nm. According to the crystal structure of serum albumin, it can be speculated that subdomain II A was the binding sites for the interaction of PTB and serum albumin, which is the region near Try214.
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Hipoglicemiantes/química , Soroalbumina Bovina/química , Albumina Sérica/química , Espectrometria de Fluorescência/métodos , Tiazóis/química , Animais , Bovinos , Transferência de Energia , Fluorescência , Humanos , Ligação Proteica , TermodinâmicaRESUMO
The role of chemokines and their receptors in HIV biology and Kaposi's sarcoma (KS) pathogenesis has recently gained considerable attention. It has been shown that KS-associated human herpes virus type 8 (KSHV/HHV-8) encodes functional homologues of certain chemokines and chemokine receptors. This suggests that chemokines may contribute to the growth and spread of KS seen in AIDS. We found the expression of CXCR4 in primary KS tissue by using in situ hybridization (ISH). Recently, alpha-chemokine receptors CXCR1 and CXCR2 have also been shown to be expressed by KS tissues. We further characterized the expression of these chemokines as well as the signaling events induced upon binding to their respective cognate ligands in the KS 38 spindle cell line. These cells express authentic characteristics of primary KS spindle cells and provide a useful in vitro model for these studies. We observed using RT-PCR that KS 38 cells express mRNA for the alpha-chemokine receptors CXCR1, CXCR2, and CXCR4. We also confirmed the cell surface protein expression by FACS analysis. Characterization of signaling pathways revealed that the alpha-chemokines, IL-8 and stromal cell-derived factor 1alpha (SDF1alpha/CXCL12), activated members of the mitogen-activated protein (MAP) kinase family, including Erk kinase, c-Jun amino terminal kinase (JNK)/stress-activated protein kinase (SAPK) and the p38 MAP kinase. Furthermore, using DNA protein-binding experiments, we have shown that IL-8 increased AP-1 and NF Kappa B activity in these cells. IL-8 also enhanced the chemotaxis of KS cells. These results reveal that chemokine-induced signaling pathways may mediate cell growth, transcriptional activation and cell migration in KS.
Assuntos
Quimiocinas CXC/metabolismo , Receptores CXCR4/metabolismo , Sarcoma de Kaposi/metabolismo , Sarcoma de Kaposi/patologia , Transdução de Sinais/fisiologia , Linhagem Celular Tumoral , Quimiocina CXCL12 , Quimiotaxia , Ativação Enzimática , Humanos , Hibridização In Situ , Interleucina-8/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Receptores CXCR4/genética , Receptores de Interleucina-8A/genética , Receptores de Interleucina-8A/metabolismo , Receptores de Interleucina-8B/genética , Receptores de Interleucina-8B/metabolismo , Fator de Transcrição AP-1/metabolismoRESUMO
OBJECTIVE: To evaluate the capillary isoelectric focusing (CIEF) method for the estimation of blood hemoglobin A2 (Hb A2) concentrations in routine thalassemia screening. METHODS: A total of 105 samples from healthy adults and 93 samples with positive phenotypes were collected by routine thalassemia screening. CIEF was compared with Helena spife combo electrophoresis system for Hb A2 measurement and its precision and reproducibility were tested by analyzing intra-assay or inter-assay coefficient of variations(CVs). The reliability and veracity of Hb A2 measurement by CIEF for the detection of alpha- and beta- thalassemia including Hb E were evaluated by genotyping of 93 consecutive samples for routine thalassemia screening. RESULTS: By us e of CIEF for measurement of Hb A2 in a local healthy adult population, the range of reference value(3.59%-5.23%) was obtained. The results of CIEF showed good linearity relation to that of conventional Hb electrophoresis assay. All thalassemia carriers (43 cases of alpha-thals and 44 of beta-thals) or Hb E carriers (6 cases) presumptively identified by the present CIEF for the quantification of Hb A2, combined with routine RBC parameters for indicating microcytosis and hypochromia were confirmed to be the heterozygous or compound heterozygous defects of alpha- or beta- globin gene by molecular diagnosis, without any false positive or false negative results. CONCLUSION: The measurement of Hb A2 by CIEF method is rapid, precise and reproducible; it could be used in routine screening for alpha- or beta- thalassemia.