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1.
Mov Ecol ; 12(1): 43, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851751

RESUMO

BACKGROUND: Successive stamen movement is a complex plant behavior involving successive uplift of stamens and pollen release, which plays a role in reducing sexual interference, increasing pollen deposition and promoting pollen export. Although reported from several taxa, studies on whether the movement can be influenced by abiotic and biotic factors are scarce. METHODS: In this study, we here for the first time described a pattern of successive stamen movement in Saxifraga candelabrum (Saxifragaceae). We then compared the rates of stamen movement in S. candelabrum under different weather and varying pollinator visits. Pollen packaging and presentation schedule of S. candelabrum were also investigated. RESULTS: The results showed that the number of stamens bent per day in sunny days was significantly higher than overcast and rain. Flowers that receive more pollinator visits (control treatment) had significantly higher number of stamen movement than those that received fewer (removal treatment) and none (bagging treatment). Throughout the staminate phase of a flower, there was a progressive increase in both pollen quantity of individual stamens and pollen presentation during each day. CONCLUSION: Our research demonstrates that successive stamen movement in S. candelabrum was accelerated by favorable weather and increased pollinator visits, which may promote pollen export. Moreover, incremental pollen packaging is likely an adaptation to seasonal regularity in variations of sex ratio resulting from protandry.

2.
J Proteome Res ; 22(10): 3332-3347, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37616386

RESUMO

Brown adipose tissue (BAT) thermogenesis confers beneficial effects on metabolic diseases such as obesity and type-2 diabetes. Nevertheless, the mechanism and lipid driving the process that evokes this response have not been investigated yet. Here, a multiomics approach of integrative transcriptomics and lipidomics is used to explore the mechanism of regulating thermogenesis in BAT and providing promising lipid biomarkers and biomarker genes for thermogenic activators as antiobesity drugs. Lipidomics analysis demonstrated that a high abundance of glycerophospholipids and sphingolipids was more significant in BAT than in WAT. Enrichment analysis of upregulated DEGs between WAT and BAT screened suggested that the differences were mainly involved in lipid metabolism. Besides, ß3-adrenergic agonist stimulation reduced the levels of TAG and DAG and increased the content of PC, PE, CL, and LPC and expression of genes involved in thermogenesis, fatty acid elongation, and glycerophospholipid metabolism in BAT. In this study, based on interpreting the inherent characterization of BAT as thermogenic tissue through comparison with WAT as fat storage tissue, adrenergic stimulation-induced BAT thermogenesis further identified specific lipid biomarkers (7 TAG species, 10 PC species, 1 LPC species, and 1 CL species) and Elovl3 and Crat gene biomarkers, which may provide targets for combating obesity by boosting BAT thermogenesis.

3.
Brain Res ; 1812: 148409, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37207839

RESUMO

Schizophrenia (SCZ) is a debilitating neuropsychiatric disorder with a complex aetiology. Cognitive symptoms and hippocampal changes have been implicated in the pathophysiology of SCZ. Changes in metabolites level and up-regulated glycolysis have been reported in previous studies, which may be related to the hippocampal dysfunction in SCZ. However, the pathological mechanism of glycolysis involved in the pathogenesis of SCZ remains unclear. Therefore, the change of glycolysis level and the involvement in SCZ need to be further studied. In our study, MK801 was used to induce an SCZ mouse model and cell model in vivo and in vitro. Western blotting was performed to evaluate the levels of glycolysis, metabolites, and lactylation in hippocampal tissue of mice with SCZ or cell models. The level of high mobility group protein 1 (HMGB1) in the medium of MK801-treated primary hippocampal neurons was examined. Apoptosis was evaluated in HMGB1-treated hippocampal neurons by flow cytometry. The glycolysis inhibitor 2-DG prevented behavioural changes in the MK801-induced SCZ mouse model. The lactate accumulation and level of lactylation were alleviated in the hippocampal tissue of MK801-treated mice. Glycolysis was enhanced, and lactate accumulated in MK-801-treated primary hippocampal neurons. In addition, the level of HMGB1 increased in the medium and induced apoptosis in primary hippocampal neurons. Together, the data showed that glycolysis and lactylation increased in the MK801-induced SCZ model in vivo and in vitro, and this effect could be prevented by 2-DG (a glycolysis inhibitor). Glycolytic related HMGB1 upregulation may induce apoptosis in hippocampal neurons downstream.


Assuntos
Proteína HMGB1 , Esquizofrenia , Camundongos , Animais , Proteína HMGB1/metabolismo , Ácido Láctico , Maleato de Dizocilpina/farmacologia , Esquizofrenia/patologia , Glicólise
4.
Front Immunol ; 12: 679897, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367139

RESUMO

Intestinal microbiota dysbiosis is an established characteristic of ulcerative colitis (UC). Regulating the gut microbiota is an attractive alternative UC treatment strategy, considering the potential adverse effects of synthetic drugs used to treat UC. Kaempferol (Kae) is an anti-inflammatory and antioxidant flavonoid derived from a variety of medicinal plants. In this study, we determined the efficacy and mechanism of action of Kae as an anti-UC agent in dextran sulfate sodium (DSS)-induced colitis mice. DSS challenge in a mouse model of UC led to weight loss, diarrhea accompanied by mucous and blood, histological abnormalities, and shortening of the colon, all of which were significantly alleviated by pretreatment with Kae. In addition, intestinal permeability was shown to improve using fluorescein isothiocyanate (FITC)-dextran administration. DSS-induced destruction of the intestinal barrier was also significantly prevented by Kae administration via increases in the levels of ZO-1, occludin, and claudin-1. Furthermore, Kae pretreatment decreased the levels of IL-1ß, IL-6, and TNF-α and downregulated transcription of an array of inflammatory signaling molecules, while it increased IL-10 mRNA expression. Notably, Kae reshaped the intestinal microbiome by elevating the Firmicutes to Bacteroidetes ratio; increasing the linear discriminant analysis scores of beneficial bacteria, such as Prevotellaceae and Ruminococcaceae; and reducing the richness of Proteobacteria in DSS-challenged mice. There was also an evident shift in the profile of fecal metabolites in the Kae treatment group. Serum LPS levels and downstream TLR4-NF-κB signaling were downregulated by Kae supplementation. Moreover, fecal microbiota transplantation from Kae-treated mice to the DSS-induced mice confirmed the effects of Kae on modulating the gut microbiota to alleviate UC. Therefore, Kae may exert protective effects against colitis mice through regulating the gut microbiota and TLR4-related signaling pathways. This study demonstrates the anti-UC effects of Kae and its potential therapeutic mechanisms, and offers novel insights into the prevention of inflammatory diseases using natural products.


Assuntos
Anti-Inflamatórios/farmacologia , Colite/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Quempferóis/farmacologia , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Biomarcadores , Colite/etiologia , Colite/patologia , Colite/terapia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Transplante de Microbiota Fecal , Feminino , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Lipopolissacarídeos/efeitos adversos , Camundongos , Permeabilidade , RNA Ribossômico 16S
5.
Front Immunol ; 12: 662362, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33981308

RESUMO

Psoriasis is a recurrent autoimmune skin disease with aberrant regulation of keratinocytes and immunocytes. There is no universally accepted single treatment available for psoriasis, and the establishment of a common treatment option to control its signs and symptoms is urgently needed. Here, we found Ebosin, a novel exopolysaccharide isolated from Streptomyces sp. 139 by our lab, not only could ameliorate inflammation in LPS-induced keratinocytes through IKK/NF-kapaB pathway, but also attenuate psoriatic skin lesions and reduce inflammatory factors expression in imiquimod (IMQ)-mediated psoriatic mice. Except for inhibiting the expression of epidermal differentiation related proteins, Ebosin significantly increased the percentage of CD4+Foxp3+CD25+ Tregs and decreased CD4+IL17A+ Th17 cells in psoriatic mice. Furthermore, we demonstrate that Ebosin significantly suppressed the IL-17 signaling pathway via A20 (encoded by tnfaip3) in vivo. As the direct binding of tnfaip3 to miR-155 has been demonstrated by luciferase reporter assay, and Ebosin has been demonstrated to inhibit miR-155 level in vitro and in vivo, our study first indicates that Ebosin reduces inflammation through the miR-155-tnfaip3-IL-17 axis and T cell differentiation in a psoriasis-like model. Thus, we conclude that Ebosin can act as a promising therapeutic candidate for the treatment of psoriasis.


Assuntos
Inflamação/prevenção & controle , Interleucina-17/metabolismo , MicroRNAs/metabolismo , Polissacarídeos Bacterianos/administração & dosagem , Psoríase/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Proliferação de Células , Modelos Animais de Doenças , Células HaCaT , Humanos , Inflamação/tratamento farmacológico , Interleucina-17/genética , Interleucina-17/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , MicroRNAs/imunologia , Polissacarídeos Bacterianos/imunologia , Psoríase/tratamento farmacológico , Psoríase/imunologia , Transdução de Sinais/imunologia , Pele/efeitos dos fármacos , Pele/imunologia , Pele/patologia , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/imunologia
6.
J Mol Neurosci ; 70(2): 269-275, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31897968

RESUMO

Schizophrenia is a severe chronic neuropsychiatric disorder, and it negatively affects individuals' quality of life, but the pathogenesis of schizophrenia remains unclear. This study aimed to explore whether the administration of ketamine in rats causes changes in mTOR (mechanistic/mammalian target of rapamycin) expression in the hippocampus and prefrontal cortex. Ketamine was used to establish an animal model of schizophrenia. Rats were randomly divided into four groups: control group (normal saline), low-dose group (15 mg/kg ketamine), middle-dose group (30 mg/kg ketamine), and high-dose group (60 mg/kg ketamine). The rats were intraperitoneally injected with ketamine or normal saline twice a day (9 AM and 9 PM) for 7 consecutive days. Immunohistochemistry was used to detect mTOR protein expression in the hippocampus and prefrontal cortex from rats at 13 h after the last treatment. Using immunohistochemistry, the expression of the mTOR protein was localized exclusively in the CA3 region of the hippocampus and in the Cg1 region of the prefrontal cortexes. Ketamine at 60 mg/kg decreased the expression of mTOR protein in the brain of rats. Ketamine successfully established a rat model of schizophrenia. This study helps elucidate the mechanisms of ketamine-induced schizophrenia and provides novel insights for drug discovery and development.


Assuntos
Modelos Animais de Doenças , Hipocampo/metabolismo , Ketamina/toxicidade , Córtex Pré-Frontal/metabolismo , Esquizofrenia/metabolismo , Serina-Treonina Quinases TOR/genética , Animais , Regulação para Baixo , Ketamina/administração & dosagem , Masculino , Ratos , Ratos Sprague-Dawley , Esquizofrenia/etiologia , Esquizofrenia/genética , Esquizofrenia/patologia , Serina-Treonina Quinases TOR/metabolismo
7.
RSC Adv ; 10(17): 10352-10360, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35498569

RESUMO

Rubropunctatin is a naturally occurring constituent of polyketide compounds that has great potential in the development of cancer-assisted chemotherapy. However, it has certain shortcomings such as water insolubility and photo instability that limit its clinical application. In this study, we constructed a Rubropunctatin-loaded liposome (R-Liposome) anticancer drug carrier for the first time. The results indicate that R-Liposome is water soluble, has spherical morphology, great homogeneity and dispersibility with high encapsulation efficiency (EE%, 90 ± 3.5%) and loading rate (LR%, 5.60 ± 2.5%) values. Moreover, the carrier improves the photostability, storage and pH stabilities of Rubropunctatin. The R-Liposome also prolongs the release of Rubropunctatin, enhances the anticancer activity of Rubropunctatin and encourages the mechanism of Rubropunctatin to promote apoptosis. Therefore, liposomal nanoparticles have great potential as drug delivery vehicles of Rubropunctatin for cancer treatment.

8.
Biosci Rep ; 39(2)2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-29769411

RESUMO

Breast cancer is a common invasive cancer in women. Ras-related protein Rab-7a (Rab7a) is involved in late endocytic trafficking, while its role in breast cancer is largely unclear. In the present study, we investigated the role of Rab7a in breast cancer. Comparing with adjacent breast tissues, Rab7a expression was increased in breast cancer tissues. Using lentivirus-mediated knockdown strategy, we found that Rab7a silencing inhibited the proliferation and colony formation of MDA-MB-231 cells. Apoptosis and G2 cell cycle arrest were induced in Rab7a knockdown. By contrast, Rab7a suppressed the apoptosis and promoted proliferation and colony formation of MCF-7 cells. The migration of MDA-MB-231 cells was suppressed by Rab7a knockdown. In vivo, depletion of Rab7a inhibited the xenograft tumor development of MDA-MB-231 cells. Altogether, our results highlight the novel function of Rab7a in the proliferation, invasion, and xenograft tumor development of breast cancer cells.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas rab de Ligação ao GTP/genética , Animais , Apoptose/genética , Neoplasias da Mama/metabolismo , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Células MCF-7 , Masculino , Camundongos , Oncogenes , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas rab de Ligação ao GTP/metabolismo , proteínas de unión al GTP Rab7
9.
Phytomedicine ; 38: 90-97, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29425659

RESUMO

BACKGROUND: Oxidative stress is concomitant with acetaminophen (APAP)-induced hepatotoxicity, which has been highlighted as therapeutic targets for such diseases. The berries of Seabuckthorn (Hippophae rhamnoides L.) have been traditionally used in Tibetan medicine for thousands of years. The effect of Seabuckthorn berry polysaccharide on drug- induced liver injury (DILI) has not yet been elucidated. PURPOSE: This study aims to investigate the protective effects and mechanisms of Seabuckthorn polysaccharide (SP) against APAP-induced hepatotoxicity. STUDY DESIGN: Sixty C57BL/6 mice were randomly divided into six groups (n = 10 per group), namely the control group (Ctrl), APAP-induced-liver injury group (APAP), NAC pretreated group (NAC), 100 mg/kg SP pretreated group (APAP/SP100), 200 mg/kg SP pretreated group (APAP/SP200) and 200 mg/kg SP pretreated group without APAP challenge (SP200). SP was given orally to mice for 30 consecutive days prior to APAP exposure (300 mg/kg). NAC (150 mg/kg) was administrated 1 h before APAP challenge. METHODS: ALT and AST were detected 16 h after APAP treatment; Hepatic expression of GSH, SOD, NO, iNOS and GSH-Px were examined. The expression of p-JNK, Bcl-2/Bax, p62, Keap-1 and SOD-2 was detected by Western blotting. The expression of Nrf-2 and its target genes HO-1, GCLC and NQO-1 were analyzed by RT-PCR and Western blotting. RESULTS: Pretreatment with SP led to decreased levels of ALT and AST in APAP mice, without affecting APAP metabolism. This was accompanied by diminished liver injuries, increased levels of GSH and GSH-Px, reduced NO and iNOS expression. SP increased the activity of SOD as well as SOD-2 expression in APAP mice. SP suppressed APAP-induced JNK phosphorylation and increased the ratio of Bcl-2/Bax. Furthermore, SP decreased the expression of Keap-1 and increased the nuclear expression of Nrf-2. The expression of Nrf-2 target gene HO-1 was increased by SP pretreatment in APAP mice. CONCLUSION: SP alleviates APAP-induced hepatotoxicity. The protective effects of SP are associated with the activation of the Nrf-2/HO-1-SOD-2 signaling pathway.


Assuntos
Acetaminofen/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Hippophae/química , Polissacarídeos/farmacologia , Substâncias Protetoras/farmacologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Frutas/química , Glutationa/metabolismo , Heme Oxigenase-1/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/química , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo
10.
Food Funct ; 8(9): 3130-3138, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28766672

RESUMO

The berries of Seabuckthorn (Hippophae rhamnoides L.) are traditional medicinal foods that have been used by Tibetans and Mongolians for thousands of years. The polysaccharides are the main components of Seabuckthorn berries, possessing immune stimulating, anti-cancer and anti-fatigue activities. The present study focused on evaluating the protective effects and mechanisms of Seabuckthorn berry polysaccharide (SP) against carbon tetrachloride (CCl4)-induced hepatotoxicity. Mice were orally administrated with 50, 100 and 200 mg kg-1 of SP once daily for 14 consecutive days prior to CCl4 challenge. Pretreatment with SP significantly decreased alanine transaminase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) levels, while increasing the levels of prealbumin (PALB) in the CCl4-challenged mice, which were accompanied by diminished liver injuries, increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, increased GSH levels, and reduced malondialdehyde (MDA) content. The pretreatment with SP also markedly reduced the CCl4-induced expression of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), inducible nitric oxide synthase (iNOS) and nitric oxide (NO). Furthermore, the pretreatment with SP decreased hepatic Toll-like receptor 4 (TLR4) expression and inhibited the phosphorylation of p38 MAPK, extracellular signal-regulated kinase (p-ERK), c-Jun N-terminal kinase (p-JNK) and nuclear factor-kappa B (NF-κB) in the CCl4-challenged mice. These results suggest that the pretreatment with SP protected against CCl4-induced liver damage via its anti-oxidative and anti-inflammatory activities. SP might be suitable for functional foods and natural drugs in preventing CCl4-induced hepatotoxicity.


Assuntos
Anti-Inflamatórios/administração & dosagem , Antioxidantes/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Hippophae/química , Extratos Vegetais/administração & dosagem , Polissacarídeos/administração & dosagem , Alanina Transaminase/genética , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/genética , Aspartato Aminotransferases/metabolismo , Tetracloreto de Carbono/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Frutas/química , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
11.
Eur J Nutr ; 55(2): 821-831, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25893720

RESUMO

PURPOSE: In this study, we sought to find the effects and mechanisms of probiotic Lactobacillus casei Zhang (L. casei Zhang) on the pro-inflammatory cytokine production and hepatic inflammatory response in a rat model of acute liver failure induced by lipopolysaccharide (LPS) and d-galactosamine (GalN). METHODS: Male Wistar rats were orally administrated with or without L. casei Zhang for 30 days prior to challenge with LPS and GalN. Dexamethasone administrated group serving as a positive anti-inflammation control. Serum, intestinal and liver samples were collected 8 h after LPS/GalN challenge for histological, molecular and biochemical analysis. RESULTS: LPS/GalN challenge alone resulted in significantly increased production of endotoxin, tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1ß) and nitric oxide as compared to the normal control rats. Pretreatment with L. casei Zhang not only reduced these changes, but also attenuated hepatic inflammation as shown by improved histological assessment, decreased myeloperoxidase activity and reduced expression of IL-1ß and inducible nitric oxide synthase in the liver. L. casei Zhang supplementation significantly inhibited LPS/GalN-triggered phosphorylation of ERK, JNK and p-38 MAPK, but increased the expression of TLR2, TLR9 and PPAR-γ. Moreover, L. casei Zhang treatment prevented intestinal injury and modulated the intestinal ecology by increasing the fecal Lactobacillus and Bifidobacterium levels. CONCLUSIONS: Probiotic L. casei Zhang reduces LPS/GalN-induced pro-inflammatory cytokine and hepatic inflammation through modulating the TLR-MAPK-PPAR-γ signaling pathways and intestinal microbiota.


Assuntos
Citocinas/metabolismo , Lacticaseibacillus casei , Hepatopatias/terapia , Fígado/microbiologia , Probióticos/administração & dosagem , Doença Aguda , Animais , Anti-Inflamatórios/farmacologia , Bifidobacterium , Dexametasona/farmacologia , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Galactosamina/efeitos adversos , Microbioma Gastrointestinal , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lipopolissacarídeos/efeitos adversos , Fígado/metabolismo , Masculino , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo
12.
J Ethnopharmacol ; 176: 69-78, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26494508

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sea buckthorn (Hippophae rhamnoides L.) berries have been traditionally used to treat gastric disorders, cardiovascular problems, and liver injuries in oriental medicinal system. This study aimed to explore the protective effects and mechanisms of the polysaccharide extracts of Sea buckthorn (HRP) berries against lipopolysaccharide (LPS) and d-galactosamine hydrochloride (d-GalN)-induced acute liver failure in mice. MATERIALS AND METHODS: HRP was isolated by hot-water extraction and characterized by HPLC and infrared spectrum analysis. The total carbohydrate, uronic acid and protein contents of HRP were measured by a spectrophotometric method. Mice were orally administrated with HRP (50, 100, 200mg/kg) once daily for 14 consecutive days prior to the challenge with LPS (50 µg/kg) and d-GalN (300 mg/kg). Animals of positive control group were intraperitoneally injected with dexamethasone (10mg/kg). Mice were sacrificed at 8h after LPS/d-GalN injection. RESULTS: Pretreatment with HRP significantly inhibited LPS/d-GalN-induced increases in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, which were accompanied by alleviated liver injuries and reduced production of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß). HRP was also found to reduce malondialdehyde (MDA) content and to restore superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities. Furthermore, HRP supplementation dose-dependently inhibited the expression of Toll-like receptor 4 (TLR4), phosphorylated extracellular signal-regulated kinase (p-ERK), phosphorylated c-Jun N-terminal kinase (p-JNK), and phosphorylated mitogen activated protein kinase 38 (p-p38 MAPK) in the liver of LPS/d-GalN challenged mice. Pretreatment with HRP also inhibited LPS/d-GalN-induced activation and translocation of nuclear factor-κB (NF-κB). CONCLUSIONS: This study indicates that pretreatment with HRP protects against LPS/d-GalN-induced liver injury in mice via suppressing the TLR4-NF-κB signaling pathway. Sea buckthorn may be a hopeful drug for prevention of acute live injury.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Hippophae , Falência Hepática Aguda/tratamento farmacológico , Polissacarídeos/uso terapêutico , Substâncias Protetoras/uso terapêutico , Alanina Transaminase/sangue , Animais , Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Antioxidantes/análise , Antioxidantes/farmacologia , Aspartato Aminotransferases/sangue , Frutas , Galactosamina , Interleucina-1beta/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/patologia , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Extratos Vegetais/química , Polissacarídeos/análise , Polissacarídeos/farmacologia , Substâncias Protetoras/análise , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/sangue
13.
Microbiol Immunol ; 57(1): 54-62, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23350674

RESUMO

Lactobacilli are frequently used as probiotics due to their beneficial effects on health. Lactobacillus casei Zhang (LcZ), which has favorable probiotic properties, was first isolated from koumiss. In this study, the immunomodulating effects of LcZ on cytokine and toll-like receptor expression in RAW264.7 macrophages was assessed and it was found that live LcZ promotes production of nitric oxide (NO), tumor necrosis factor (TNF)-α, interleukin (IL)-6 and interferon (IFN)-ß. Transcription of inducible nitric oxide synthase (iNOS) was also enhanced by viable LcZ. The immunostimulating effects of live LcZ are significantly attenuated in heat-killed LcZ. Live LcZ promotes TLR2 mRNA transcription, whereas heat-killed LcZ enhances transcription of TLR2, TLR3, TLR4 and TLR9. Furthermore, live LcZ significantly suppresses polyinosinic:polycytidylic acid (poly I:C)-stimulated NO, iNOS and TNF-α expression while enhancing expression of IFN-ß. It was also found that poly I:C-induced interferon regulatory factor 3 (IRF-3) reporter gene activity was significantly up-regulated by live LcZ. These results suggest that LcZ keeps the innate immune system alert by increasing transcription of Toll-like receptors and enhancing production of pro-inflammatory mediators and type I IFN in macrophages. The synergistic effect of live LcZ with poly I:C on IFN-ß expression is associated with increased activity of IRF-3. LcZ has the potential to be used as an adjuvant against viral infections.


Assuntos
Citocinas/metabolismo , Lacticaseibacillus casei/imunologia , Macrófagos/imunologia , Poli I-C/imunologia , Receptores Toll-Like/biossíntese , Animais , Linhagem Celular , Perfilação da Expressão Gênica , Camundongos , Óxido Nítrico/metabolismo
14.
Int Immunopharmacol ; 15(1): 30-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23146349

RESUMO

Lactobacillus casei Zhang (LcZ) has been recently isolated from the traditional Mongolian beverage koumiss and has a set of favorable probiotic properties, including aciduricity, bile resistance and ability to colonize the gastrointestinal tract. We have previously reported the anti-oxidative properties of LcZ in the hyperlipidemic rats. In this study, the hepatoprotective effects of LcZ against lipopolysaccharide (LPS) and d-galactosamine (D-GalN)-induced liver injury were investigated. We found that pretreatment with LcZ significantly improved survival of rats challenged with LPS/D-GalN. In addition, pretreatment with LcZ significantly decreased alanine transaminase (ALT) and aspartate aminotransferase (AST) levels in LPS/D-GalN-challenged rats, which were accompanied by diminished liver injuries, reduced malondialdehyde (MDA) content and increased superoxide dismutase (SOD) activity in liver homogenates. Pretreatment with LcZ also markedly reduced LPS/D-GalN-induced production of hepatic nitric oxide (NO), activation of inducible nitric oxide synthase (iNOS) and expression of tumor necrosis factor-α (TNF-α). Furthermore, hepatic toll-like receptor 4 (TLR4) mRNA and protein levels, the phosphorylation of I-κB and translocation of nuclear factor κB (NF-κB) were significantly down-regulated by pretreatment with LcZ. These results suggest that pretreatment with LcZ protects against LPS/D-GalN-induced liver injury in rats via its anti-oxidative and anti-inflammatory capacities. The hepatoprotective effects of LcZ are associated with an inhibition of TLR4 expression and TLR4 signaling.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Lacticaseibacillus casei , Probióticos/uso terapêutico , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Endotoxinas/efeitos adversos , Galactosamina/efeitos adversos , Masculino , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismo
15.
Comput Biol Med ; 37(3): 315-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16716287

RESUMO

Quantitative structure-retention relationship (QSRR) models have been used successfully to predict and explain retention behavior of pigments in reversed-phase high-performance liquid chromatography (HPLC). The semi-empirical quantum chemical method (PM3) in Gaussian98 was employed to calculate a set of molecular descriptors of pigments. Using multiple linear regression (MLR), we obtained empirical functions with high correlation coefficient between retention times and quantum-chemical descriptors. This analysis indicated that the proposed QSRR models were satisfactory.


Assuntos
Cromatografia Líquida de Alta Pressão , Corantes/química , Corantes de Alimentos/química , Modelos Teóricos , Processamento de Sinais Assistido por Computador , Software , Humanos , Modelos Lineares , Modelos Moleculares , Modelos Estatísticos , Conformação Molecular , Distribuição Normal , Pontos Quânticos , Relação Estrutura-Atividade
16.
Bioorg Med Chem ; 13(9): 3169-73, 2005 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-15809152

RESUMO

Quantitative structure-retention relationship (QSRR) models for the chromatographic (GC) retention times of alcohols on Superox 20M-diglycerol polarity stationary phase have been developed. Semi-empirical quantum chemical method (AM1) in MOPAC and Hartree-Fock (HF) method in Gaussian 98 implemented were employed to calculate a set of molecular descriptors of alcohols and ethyl acetate. Using multiple linear regression (MLR), we obtained the empirical functions with high correlation coefficient between retention times and quantum-chemical descriptors. The retention mechanism of alcohols of separation operating in the gas chromatogram was discussed. The results indicated that the QSRR models proposed were satisfactory.


Assuntos
Álcoois/química , Relação Quantitativa Estrutura-Atividade , Fenômenos Químicos , Físico-Química , Cromatografia Gasosa/métodos , Modelos Químicos , Modelos Moleculares , Estrutura Molecular , Fatores de Tempo
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