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1.
J Appl Microbiol ; 129(2): 422-433, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32119175

RESUMO

AIM: The aim was to identify a Lactobacillus strain with potential probiotic characteristics by whole-genome sequence analysis and in vitro experimental studies. METHODS AND RESULTS: The whole-genome sequencing was carried out using PacBio RSII sequencing method and Illumina's paired-end sequencing technology. Gene prediction and annotation were achieved using GlimmerVersion 3.02 and NCBI prokaryotic Genome Annotation Pipeline. Identification was done by biochemical tests and 16S rRNA sequence analysis. mega 6 software was used to build phylogenetic tree. Antagonism against pathogen was determined by agar well diffusion method. Resistance and stability to bile, simulated gastric acid, different salt concentration and thermostability were investigated. Hydrophobicity assay, aggregation assay and anti-oxidation assay were performed to check further probiotic traits. Finally antibiotic susceptibility and acute oral toxicity of the strain in mice were investigated to check its safety status. The strain showed >99% similarity to Lactobacillus paracasei which was further confirmed by biochemical tests. It significantly inhibited pathogens in agar well diffusion assay. It showed tolerance to simulated gastric acid (pH 3), 0·3% bile salt and 10% NaCl. Significant hydrophobic, aggregation and anti-oxidizing activities were observed. No resistance to antibiotics tested was observed and no adverse effects during acute oral toxicity in mice were detected. CONCLUSIONS: Lactobacillus paracasei ZFM 54, a new and safe Lactobacillus strain was identified with numerous probiotic-associated genes and characteristics confirmed by experimental studies. SIGNIFICANCE AND IMPACT OF THE STUDY: A new probiotic strain has been identified which is highly stable, safe and suitable to be used in health and food industries.


Assuntos
Genoma Bacteriano/genética , Lactobacillus paracasei/fisiologia , Probióticos , Animais , Antibacterianos/farmacologia , Antibiose , Ácidos e Sais Biliares/farmacologia , Inocuidade dos Alimentos , Lactobacillus paracasei/classificação , Lactobacillus paracasei/efeitos dos fármacos , Lactobacillus paracasei/genética , Camundongos , Filogenia , Probióticos/administração & dosagem , Probióticos/classificação , Probióticos/farmacologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
2.
Am J Physiol Gastrointest Liver Physiol ; 318(4): G682-G693, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32003602

RESUMO

Postprandial dyslipidemia is a common feature of insulin-resistant states and contributes to increased cardiovascular disease risk. Recently, bile acids have been recognized beyond their emulsification properties as important signaling molecules that promote energy expenditure, improve insulin sensitivity, and lower fasting lipemia. Although bile acid receptors have become novel pharmaceutical targets, their effects on postprandial lipid metabolism remain unclear. Here, we investigated the potential role of bile acids in regulation of postprandial chylomicron production and triglyceride excursion. Healthy C57BL/6 mice were given an intraduodenal infusion of taurocholic acid (TA) under fat-loaded conditions, and circulating lipids were measured. Targeting of bile acid receptors was achieved with GW4064, a synthetic agonist to the farnesoid X receptor (FXR), and deoxycholic acid (DCA), an activator of the Takeda G-protein-coupled receptor 5. TA, GW4064, and DCA treatments all lowered postprandial lipemia. FXR agonism also reduced intestinal triglyceride content and activity of microsomal triglyceride transfer protein, involved in chylomicron assembly. Importantly, TA (but not DCA) effects were largely lost in FXR knockout mice. These bile acid effects are reminiscent of the antidiabetic hormone glucagon-like peptide-1 (GLP-1). Although the GLP-1 receptor agonist exendin-4 retained its ability to acutely lower postprandial lipemia during bile acid sequestration and FXR deficiency, it did raise hepatic expression of the rate-limiting enzyme for bile acid synthesis. Bile acid signaling may be an important mechanism of controlling dietary lipid absorption, and bile acid receptors may constitute novel targets for the treatment of postprandial dyslipidemia.NEW & NOTEWORTHY We present new data suggesting potentially important roles for bile acids in regulation of postprandial lipid metabolism. Specific bile acid species, particularly secondary bile acids, were found to markedly inhibit absorption of dietary lipid and reduce postprandial triglyceride excursion. These effects appear to be mediated via bile acid receptors, farnesoid X receptor (FXR) and Takeda G protein-coupled receptor 5 (TGR5). Importantly, bile acid signaling may trigger glucagon-like peptide-1 (GLP-1) secretion, which may in turn mediate the marked inhibitory effects on dietary fat absorption.


Assuntos
Ácido Desoxicólico/farmacologia , Hiperlipidemias/tratamento farmacológico , Isoxazóis/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Período Pós-Prandial , Receptores Citoplasmáticos e Nucleares/agonistas , Animais , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo , Exenatida/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/sangue , Mucosa Intestinal , Intestinos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores Acoplados a Proteínas-G/agonistas , Ácido Taurocólico/farmacologia
3.
Diabetes ; 69(4): 614-623, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32041793

RESUMO

Glucagon-like peptide 1 (GLP-1) mimetics are effective drugs for treatment of type 2 diabetes, and there is consequently extensive interest in increasing endogenous GLP-1 secretion and L-cell abundance. Here we identify G-protein-coupled bile acid receptor 1 (GPBAR1) as a selective regulator of intestinal L-cell differentiation. Lithocholic acid and the synthetic GPBAR1 agonist, L3740, selectively increased L-cell density in mouse and human intestinal organoids and elevated GLP-1 secretory capacity. L3740 induced expression of Gcg and transcription factors Ngn3 and NeuroD1 L3740 also increased the L-cell number and GLP-1 levels and improved glucose tolerance in vivo. Further mechanistic examination revealed that the effect of L3740 on L cells required intact GLP-1 receptor and serotonin 5-hydroxytryptamine receptor 4 (5-HT4) signaling. Importantly, serotonin signaling through 5-HT4 mimicked the effects of L3740, acting downstream of GLP-1. Thus, GPBAR1 agonists and other powerful GLP-1 secretagogues facilitate L-cell differentiation through a paracrine GLP-1-dependent and serotonin-mediated mechanism.


Assuntos
Ácidos e Sais Biliares/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Enteroendócrinas/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Comunicação Parácrina/fisiologia , Receptores Acoplados a Proteínas-G/metabolismo , Serotonina/metabolismo , Animais , Células Enteroendócrinas/fisiologia , Feminino , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Jejuno/efeitos dos fármacos , Jejuno/metabolismo , Masculino , Camundongos , Comunicação Parácrina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
4.
PLoS One ; 15(1): e0227751, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31971960

RESUMO

One of the most promising applications of human pluripotent stem cells is their utilization for human-based pharmacological models. Despite the fact that membrane transporters expressed in the liver play pivotal role in various hepatic functions, thus far only little attention was devoted to the membrane transporter composition of the stem cell-derived liver models. In the present work, we have differentiated HUES9, a human embryonic stem cell line, toward the hepatic lineage, and monitored the expression levels of numerous differentiation marker and liver transporter genes with special focus on ABC transporters. In addition, the effect of bile acid treatment and polarizing culturing conditions on hepatic maturation has been assessed. We found that most transporter genes crucial for hepatic functions are markedly induced during hepatic differentiation; however, as regards the transporter composition the end-stage cells still exhibited dual, hepatocyte and cholangiocyte character. Although the bile acid treatment and sandwich culturing only slightly influenced the gene expressions, the stimulated cell polarization resulted in formation of bile canaliculi and proper localization of transporters. Our results point to the importance of membrane transporters in human stem cell-derived hepatic models and demonstrate the relevance of cell polarization in generation of applicable cellular models with correctly localized transporters. On the basis of our observations we suggest that conventional criteria for the evaluation of the quality of stem cell-derived hepatocyte-like cells ought to be augmented with additional elements, such as polarized and functional expression of hepatic transporters.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Hepatócitos/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Ácidos e Sais Biliares/farmacologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Linhagem Celular , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
5.
Proc Natl Acad Sci U S A ; 117(3): 1700-1710, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31896578

RESUMO

Human noroviruses (HuNoVs) cause sporadic and epidemic outbreaks of gastroenteritis in all age groups worldwide. We previously reported that stem cell-derived human intestinal enteroid (HIE) cultures support replication of multiple HuNoV strains and that some strains (e.g., GII.3) replicate only in the presence of bile. Heat- and trypsin-treatment of bile did not reduce GII.3 replication, indicating a nonproteinaceous component in bile functions as an active factor. Here we show that bile acids (BAs) are critical for GII.3 replication and replication correlates with BA hydrophobicity. Using the highly effective BA, glycochenodeoxycholic acid (GCDCA), we show BAs act during the early stage of infection, BA-dependent replication in HIEs is not mediated by detergent effects or classic farnesoid X receptor or Takeda G protein-coupled receptor 5 signaling but involves another G protein-coupled receptor, sphingosine-1-phosphate receptor 2, and BA treatment of HIEs increases particle uptake. We also demonstrate that GCDCA induces multiple cellular responses that promote GII.3 replication in HIEs, including enhancement of 1) endosomal uptake, 2) endosomal acidification and subsequent activity of endosomal/lysosomal enzyme acid sphingomyelinase (ASM), and 3) ceramide levels on the apical membrane. Inhibitors of endosomal acidification or ASM reduce GII.3 infection and exogenous addition of ceramide alone permits infection. Furthermore, inhibition of lysosomal exocytosis of ASM, which is required for ceramide production at the apical surface, decreases GII.3 infection. Together, our results support a model where GII.3 exploits rapid BA-mediated cellular endolysosomal dynamic changes and cellular ceramide to enter and replicate in jejunal HIEs.


Assuntos
Ácidos e Sais Biliares/metabolismo , Ceramidas/metabolismo , Intestinos/virologia , Norovirus/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Ácidos e Sais Biliares/farmacologia , Ceramidas/farmacologia , Ácido Glicoquenodesoxicólico , Humanos , Receptores Acoplados a Proteínas-G , Esfingomielina Fosfodiesterase/metabolismo , Receptores de Esfingosina-1-Fosfato
6.
Infect Immun ; 88(3)2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31818958

RESUMO

The twin-arginine translocation (Tat) system is involved in not only a wide array of cellular processes but also pathogenesis in many bacterial pathogens; thus, this system is expected to become a novel therapeutic target to treat infections. To the best of our knowledge, involvement of the Tat system has not been reported in the gut infection caused by Citrobacter rodentium Here, we studied the role of Tat in C. rodentium gut infection, which resembles human infection with enterohemorrhagic Escherichia coli (EHEC) and enteropathogenic E. coli (EPEC). A C. rodentium Tat loss-of-function mutant displayed prolonged gut colonization, which was explained by reduced inflammatory responses and, particularly, neutrophil infiltration. Further, the Tat mutant had colonization defects upon coinfection with the wild-type strain of C. rodentium The Tat mutant also became hypersensitive to bile acids, and an increase in fecal bile acids fostered C. rodentium clearance from the gut lumen. Finally, we show that the chain form of C. rodentium cells, induced by a Tat-dependent cell division defect, exhibits impaired resistance to bile acids. Our findings indicate that the Tat system is involved in gut colonization by C. rodentium, which is associated with neutrophil infiltration and resistance to bile acids. Interventions that target the Tat system, as well as luminal bile acids, might thus be promising therapeutic strategies to treat human EHEC and EPEC infections.


Assuntos
Citrobacter rodentium/patogenicidade , Infecções por Enterobacteriaceae/imunologia , Trato Gastrointestinal/microbiologia , Sistema de Translocação de Argininas Geminadas/fisiologia , Animais , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Citrobacter rodentium/efeitos dos fármacos , Citrobacter rodentium/fisiologia , Infecções por Enterobacteriaceae/microbiologia , Trato Gastrointestinal/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
7.
Am J Physiol Lung Cell Mol Physiol ; 318(2): L264-L275, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31800261

RESUMO

Duodenogastroesophageal reflux (DGER) is associated with chronic lung disease. Bile acids (BAs) are established markers of DGER aspiration and are important risk factors for reduced post-transplant lung allograft survival by disrupting the organ-specific innate immunity, facilitating airway infection and allograft failure. However, it is unknown whether BAs also affect airway reactivity. We investigated the acute effects of 13 BAs detected in post-lung-transplant surveillance bronchial washings (BW) on airway contraction. We exposed precision-cut slices from human and mouse lungs to BAs and monitored dynamic changes in the cross-sectional luminal area of peripheral airways using video phase-contrast microscopy. We also used guinea pig tracheal rings in organ baths to study BA effects in proximal airway contraction induced by electrical field stimulation. We found that most secondary BAs at low micromolar concentrations strongly and reversibly relaxed smooth muscle and inhibited peripheral airway constriction induced by acetylcholine but not by noncholinergic bronchoconstrictors. Similarly, secondary BAs strongly inhibited cholinergic constrictions in tracheal rings. In contrast, TC-G 1005, a specific agonist of the BA receptor Takeda G protein-coupled receptor 5 (TGR5), did not cause airway relaxation, and Tgr5 deletion in knockout mice did not affect BA-induced relaxation, suggesting that this receptor is not involved. BAs inhibited acetylcholine-induced inositol phosphate synthesis in human airway smooth muscle cells overexpressing the muscarinic M3 receptor. Our results demonstrate that select BAs found in BW of patients with lung transplantation can affect airway reactivity by inhibiting the cholinergic contractile responses of the proximal and peripheral airways, possibly by acting as antagonists of M3 muscarinic receptors.


Assuntos
Acetilcolina/metabolismo , Ácidos e Sais Biliares/farmacologia , Broncoconstrição/efeitos dos fármacos , Pulmão/fisiopatologia , Animais , Broncoconstritores/farmacologia , Ácido Quenodesoxicólico/farmacologia , Estimulação Elétrica , Cobaias , Humanos , Fosfatos de Inositol/biossíntese , Pulmão/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Receptores Muscarínicos/metabolismo , Serotonina/farmacologia , Ácido Taurolitocólico/farmacologia , Traqueia/efeitos dos fármacos
8.
Ecotoxicol Environ Saf ; 187: 109812, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31669574

RESUMO

Marine biofouling represents a global economic and ecological challenge. Some marine organisms produce bioactive metabolites, such as steroids, that inhibit the settlement and growth of fouling organisms. The aim of this work was to explore bile acids as a new scaffold with antifouling (AF) activity by using chemical synthesis to produce a series of bile acid derivatives with optimized AF performance and understand their structure-activity relationships. Seven bile acid derivatives were successfully synthesized in moderate to high yields, and their structures were elucidated through spectroscopic methods. Their AF activities were tested against both macro- and microfouling communities. The most potent bile acid against the settlement of Mytilus galloprovincialis larvae was the methyl ester derivative of cholic acid (10), which showed an EC50 of 3.7 µM and an LC50/EC50 > 50 (LC50 > 200 µM) in AF effectiveness vs toxicity studies. Two derivatives of deoxycholic acid (5 and 7) potently inhibited the growth of biofilm-forming marine bacteria with EC50 values < 10 µM, and five bile acids (1, 5, and 7-9) potently inhibited the growth of diatoms, showing EC50 values between 3 and 10 µM. Promising AF profiles were achieved with some of the synthesized bile acids by combining antimacrofouling and antimicrofouling activities. Initial studies on the incorporation of one of these promising bile acid derivatives in polymeric coatings, such as a marine paint, demonstrated the ability of these compounds to generate coatings with antimacrofouling activity.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Ácidos e Sais Biliares/farmacologia , Incrustação Biológica/prevenção & controle , Desinfetantes/farmacologia , Pintura , Animais , Organismos Aquáticos/crescimento & desenvolvimento , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Ácidos e Sais Biliares/síntese química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Desinfetantes/síntese química , Microalgas/efeitos dos fármacos , Microalgas/crescimento & desenvolvimento , Mytilus/efeitos dos fármacos , Poliuretanos/química , Silicones/química
9.
J Med Microbiol ; 68(12): 1771-1786, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31613203

RESUMO

Introduction. There is an ever present need to isolate and characterize indigenous bacterial strains with potential probiotic health benefits for humans.Aim. Lactobacillus fermentum of dairy origin was focused because of its propensity to adhere to the intestinal glycoprotein, mucin.Methodology. The lactobacillus strains were screened for mucin adhesion, resistance to low pH and bile, autoaggregation, hydrophobicity, and survival in an in vitro digestion model. The cholesterol-lowering and oxalate-degrading effects of selected strains were also determined. Safety was assessed for haemolytic, mucinolytic and gelatinase activity, biogenic amine production, antibiotic resistance and phenol resistance. Expression of the 32-mmub adhesion-related gene was also measured following strain exposure to simulated gastrointestinal tract (GIT) digestion.Results. The selected mucin-adhesive strains were tolerant to acid (pH 3.0) and bile (0.25 %) and demonstrated >85 % survival following simulated human digestion in the presence of milk. The digestive treatment did not affect the adhesive potential of PL20, and PL27, regardless of the food matrix. The simulated digestion had less effect on their adhesion than on the type strain and it also did not correlate with the mmub gene expression level as determined by qPCR. The selected strains exhibited cholesterol removal (36-44 %) and degraded oxalate (66-55 %). Neither of these strains exhibited undesirable characteristics.Conclusion. These preliminary findings suggest a functionality in the two strains of L. fermentum with high colonization potential on GIT mucosal membranes and possible health-promoting effects. This prima facie evidence suggests the need for further studies to test these probiotic candidates as live biotherapeutic agents in vivo.


Assuntos
Aderência Bacteriana , Laticínios/microbiologia , Digestão , Trato Gastrointestinal/metabolismo , Lactobacillus fermentum/fisiologia , Mucinas/metabolismo , Ácidos e Sais Biliares/farmacologia , Determinação da Acidez Gástrica , Interações Hidrofóbicas e Hidrofílicas , Lactobacillus fermentum/efeitos dos fármacos , Lactobacillus fermentum/isolamento & purificação , Probióticos
10.
Molecules ; 24(17)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480402

RESUMO

The current chemotherapy of Chagas disease needs to be urgently improved. With this aim, a series of 16 hybrids of Cinchona alkaloids and bile acids were prepared by functionalization at position C-2 of the quinoline nucleus by a radical attack of a norcholane substituent via a Barton-Zard decarboxylation reaction. The antitrypanosomal activity of the hybrids was tested on different stages and strains of T. cruzi. In particular, eight out of 16 hybrids presented an IC50 ≤1 µg/mL against trypomastigotes of the CL Brener strain and/or a selectivity index higher than 10. These promising hybrids yielded similar results when tested on trypomastigotes from the RA strain of T. cruzi (discrete typing unit-DTU-VI). Surprisingly, trypomastigotes of the Y strain (DTU II) were more resistant to benznidazole and to most of the hybrids than those of the CL Brener and RA strains. However, the peracetylated and non-acetylated forms of the cinchonine/chenodeoxycholic bile acid conjugate 4f and 5f were the most trypanocidal hybrids against Y strain trypomastigotes, with IC50 values of 0.5 and 0.65 µg/mL, respectively. More importantly, promising results were observed in invasion assays using the Y strain, where hybrids 5f and 4f induced a significant reduction in intracellular amastigotes and on the release of trypomastigotes from infected cells.


Assuntos
Antiparasitários/farmacologia , Ácidos e Sais Biliares/farmacologia , Alcaloides de Cinchona/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Chlorocebus aethiops , Concentração Inibidora 50 , Espaço Intracelular/parasitologia , Ratos , Células Vero
11.
Future Microbiol ; 14: 949-955, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31373220

RESUMO

Aim: Bile salts promote the specific autolysis of pneumococcal cells, allowing the differentiation between Streptococcus pneumoniae and other viridans group streptococci (VGS). Material & methods: One hundred clinical VGS isolates identified by amplification and sequencing of 16S rRNA, groEL and sodA genes were analyzed with different variants of bile-solubility tests: tube testing read by naked eye; tube testing where the lysis was measured as the decrease of turbidity with a densitometer; and direct testing on blood agar plate. Results: As expected, all S. pneumoniae isolates were fully lysed in the presence of bile salts except for one isolate that partially lysate in tube testing as well as on the blood agar plate. None of the VGS were lysed by bile salts. Conclusion: Bile-solubility testing is an accurate and technically nondemanding method to discriminate between S. pneumoniae and other VGS species.


Assuntos
Técnicas Bacteriológicas/métodos , Ácidos e Sais Biliares , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Streptococcus pneumoniae/isolamento & purificação , Estreptococos Viridans/isolamento & purificação , Bacteriólise/efeitos dos fármacos , Ácidos e Sais Biliares/farmacologia , Diagnóstico Diferencial , Humanos , Sensibilidade e Especificidade , Solubilidade
12.
J Med Microbiol ; 68(9): 1359-1366, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31364964

RESUMO

Methodology. Biochemical and molecular methods were used to identify 100 lactobacilli isolated from rectal swabs. Among these, L. paracasei ssp. paracasei LP5 and L. brevis LP9 showed significant antibacterial activity against S. agalactiae and L. monocytogenes. Accordingly, characterization of their bacteriocins, BacLP5 and BacLP9, was conducted to obtain information on their kinetic production, sensitivity to chemico-physical parameters and molecular weight. To investigate the possible use of the two Lactobacillus strains as probiotics, their gastrointestinal resistance, cellular adhesiveness and sensitivity to antibiotics were also studied.Results. The obtained data show that BacLP5 and BacLP9 most likely belong to class II bacteriocins and both have a molecular weight of approximately 3 kDa. The production of BacLP5 and BacLP9 started after 4 h (40 and 80 AU ml-1), respectively. Both of the Lactobacillus strains survived gastric and intestinal juices well and showed adhesive capability on HEp-2 cells.Conclusion. Due to their peculiar antimicrobial characteristics, L. paracasei ssp. paracasei LP5 and L. brevis LP9 are suitable for use in the treatment of vaginal disorders, through both oral and transvaginal administration.


Assuntos
Antibacterianos/metabolismo , Bacteriocinas/metabolismo , Lactobacillus brevis/metabolismo , Lactobacillus paracasei/metabolismo , Antibacterianos/química , Antibacterianos/isolamento & purificação , Aderência Bacteriana , Bacteriocinas/química , Bacteriocinas/isolamento & purificação , Ácidos e Sais Biliares/farmacologia , Linhagem Celular , Fenômenos Químicos , Suco Gástrico/metabolismo , Humanos , Lactobacillus brevis/classificação , Lactobacillus brevis/isolamento & purificação , Lactobacillus paracasei/classificação , Lactobacillus paracasei/isolamento & purificação , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Peso Molecular , Probióticos , Reto/microbiologia , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/crescimento & desenvolvimento
13.
Chem Pharm Bull (Tokyo) ; 67(10): 1082-1087, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31391385

RESUMO

Camptothecin (CPT), a natural alkaloid, possesses potent anticancer activity. However, its application was terminated due to its low bioavailability and high toxicity. This work evaluated the potential of deoxycholic acid-CPT conjugate (G2) to improve the oral absorption of CPT. Deoxycholic acid significantly reduced cytotoxicity and inhibited the uptake of G2, in vitro. And G2 showed sodium-dependent uptake. In addition, in vivo study in rats indicated that the oral bioavailability of G2 was 2.06-fold higher than that of CPT. The present study suggested that using bile acid as the conjugated moiety is a hopeful strategy to improve the oral bioavailability of CPT.


Assuntos
Ácidos e Sais Biliares/administração & dosagem , Ácidos e Sais Biliares/química , Camptotecina/administração & dosagem , Camptotecina/química , Absorção Fisiológica , Administração Oral , Animais , Ácidos e Sais Biliares/farmacologia , Células CACO-2 , Camptotecina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Masculino , Conformação Molecular , Ratos , Ratos Sprague-Dawley
14.
PLoS Genet ; 15(7): e1008224, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31276487

RESUMO

The gastrointestinal pathogen, Clostridioides difficile, initiates infection when its metabolically dormant spore form germinates in the mammalian gut. While most spore-forming bacteria use transmembrane germinant receptors to sense nutrient germinants, C. difficile is thought to use the soluble pseudoprotease, CspC, to detect bile acid germinants. To gain insight into CspC's unique mechanism of action, we solved its crystal structure. Guided by this structure, we identified CspC mutations that confer either hypo- or hyper-sensitivity to bile acid germinant. Surprisingly, hyper-sensitive CspC variants exhibited bile acid-independent germination as well as increased sensitivity to amino acid and/or calcium co-germinants. Since mutations in specific residues altered CspC's responsiveness to these different signals, CspC plays a critical role in regulating C. difficile spore germination in response to multiple environmental signals. Taken together, these studies implicate CspC as being intimately involved in the detection of distinct classes of co-germinants in addition to bile acids and thus raises the possibility that CspC functions as a signaling node rather than a ligand-binding receptor.


Assuntos
Proteínas de Bactérias/metabolismo , Ácidos e Sais Biliares/farmacologia , Proteínas de Transporte/metabolismo , Clostridium difficile/fisiologia , Esporos Bacterianos/crescimento & desenvolvimento , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Transporte/química , Proteínas de Transporte/genética , Cristalografia por Raios X , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Modelos Moleculares , Mutação , Conformação Proteica , Estresse Fisiológico
15.
Drug Metab Pharmacokinet ; 34(4): 264-271, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31285099

RESUMO

Cholestatic drug-induced liver injury (DILI) is a type of hepatotoxicity. Its underlying mechanisms are dysfunction of bile salt export pump (BSEP) and multidrug resistance-associated protein 2/3/4 (MRP2/3/4), which play major roles in bile acid (BA) excretion into the bile canaliculi and blood, resulting in accumulation of BAs in hepatocytes. The sandwich-cultured hepatocyte (SCH) model can simultaneously analyze hepatic uptake and biliary excretion. Therefore, we investigated whether sandwich-cultured human induced pluripotent stem cell (iPS cell)-derived hepatocytes (SCHiHs) are suitable for evaluating cholestatic DILI. Fluorescent N-(24-[7-(4-N,N-dimethylaminosulfonyl-2,1,3-benzoxadiazole)]amino-3α,7α,12α-trihydroxy-27-nor-5ß-cholestan-26-oyl)-2'-aminoethanesulfonate (tauro-nor-THCA-24-DBD, a BSEP substrate) was accumulated in bile canaliculi, which supports the presence of a functional bile canaliculi lumen. MRP2 was highly expressed in the Western blot analysis, whereas the mRNA expression of BSEP was hardly detectable. MRP3/4 mRNA levels were maintained. Of the 22 compounds known to cause DILI with BAs, 7 showed significant cytotoxicity. Most high-risk drugs were detected using the developed SCHiH system. However, a shortcoming was the considerably low expression level of BSEP, which prevented the detection of some relevant drugs whose risks should be detected in primary human hepatocytes.


Assuntos
Ácidos e Sais Biliares/farmacologia , Hepatócitos/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo
16.
Pharmacol Res ; 146: 104333, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31254667

RESUMO

Bile acids are endogenous emulsifiers synthesized from cholesterol having a peculiar amphiphilic structure. Appreciation of their beneficial effects on human health, recognized since ancient times, has expanded enormously since the discovery of their role as signaling molecules. Activation of farnesoid X receptor (FXR) and Takeda G-protein receptor-5 (TGR5) signaling pathways by bile acids, regulating glucose, lipid and energy metabolism, have become attractive avenue for metabolic syndrome treatment. Therefore, extensive effort has been directed into the research and synthesis of bile acid derivatives with improved pharmacokinetic properties and high potency and selectivity for these receptors. Minor modifications in the structure of bile acids and their derivatives may result in fine-tuning modulation of their biological functions, and most importantly, in an evasion of undesired effect. A great number of semisynthetic bile acid analogues have been designed and put in preclinical and clinical settings. Obeticholic acid (INT-747) has achieved the biggest clinical success so far being in use for the treatment of primary biliary cholangitis. This review summarizes and critically evaluates the key chemical modifications of bile acids resulting in development of novel semisynthetic derivatives as well as the current status of their preclinical and clinical evaluation in the treatment of metabolic syndrome, an aspect that is so far lacking in the scientific literature. Taking into account the balance between therapeutic benefits and potential adverse effects associated with specific structure and mechanism of action, recommendations for future studies are proposed.


Assuntos
Ácidos e Sais Biliares/farmacologia , Ácidos e Sais Biliares/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Animais , Humanos , Síndrome Metabólica/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
Am J Physiol Endocrinol Metab ; 317(3): E494-E502, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31237451

RESUMO

Bile acids, glucagon-like peptide-1 (GLP-1), and fibroblast growth factor 19 (FGF19) play an important role in postprandial metabolism. In this study, we investigated the postprandial bile acid response in plasma and its relation to insulin, GLP-1, and FGF19. First, we investigated the postprandial response to 40-h fast. Then we administered glycine-conjugated deoxycholic acid (gDCA) with the meal. We performed two separate observational randomized crossover studies on healthy, lean men. In experiment 1: we tested 4-h mixed meal after an overnight fast and a 40-h fast. In experiment 2, we tested a 4-h mixed meal test with and without gDCA supplementation. Both studies measured postprandial glucose, insulin, bile acids, GLP-1, and FGF19. In experiment 1, 40 h of fasting induced insulin resistance and increased postprandial GLP-1 and FGF19 concentrations. After an overnight fast, we observed strong correlations between postprandial insulin and gDCA levels at specific time points. In experiment 2, administration of gDCA increased GLP-1 levels and lowered late postprandial glucose without effect on FGF19. Energy expenditure was not affected by gDCA administration. Unexpectedly, 40 h of fasting increased both GLP-1 and FGF19, where the former appeared bile acid independent and the latter bile acid dependent. Second, a single dose of gDCA increased postprandial GLP-1. Therefore, our data add complexity to the physiological regulation of the enterokines GLP-1 and FGF19 by bile acids.


Assuntos
Ácidos e Sais Biliares/farmacologia , Jejum/fisiologia , Fatores de Crescimento de Fibroblastos/biossíntese , Peptídeo 1 Semelhante ao Glucagon/biossíntese , Ácidos e Sais Biliares/sangue , Glicemia , Estudos Cross-Over , Ácido Desoxicólico/farmacologia , Suplementos Nutricionais , Metabolismo Energético , Fatores de Crescimento de Fibroblastos/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Período Pós-Prandial , Adulto Jovem
18.
PLoS One ; 14(6): e0218922, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242260

RESUMO

The present study aimed to evaluate the probiotic characteristics of certain microbial strains for potential use as feed additives. Three bacterial strains and a yeast previously isolated from different environments were investigated. The strains were subjected to molecular identification and established as Lactobacillus paracasei CP133, Lactobacillus plantarum CP134, Bacillus subtilis CP350 and Saccharomyces cerevisiae CP605. Lactobacillus sp. CP133 and CP134 exhibited antibiosis, antibiotic activity, and relative odor reduction ability. Bacillus subtilis CP350 was thermotolerant, reduced hydrogen sulfide gas and showed significant proteolytic activity, whereas Saccharomyces cerevisiae CP605 exhibited high acid and bile salt tolerance. In general, the isolates in this study demonstrated improved functional characteristics, particularly acid and bile tolerance and relative cell adhesion to HT-29 monolayer cell line. Results in this work provides multifunctional probiotic characteristics of the strains for potential development of probiotics and cleaning of the environment.


Assuntos
Ração Animal/microbiologia , Bactérias/crescimento & desenvolvimento , Probióticos/farmacologia , Antibacterianos/farmacologia , Antibiose/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Ácidos e Sais Biliares/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Microbiologia de Alimentos/métodos , Células HT29 , Humanos , Lactobacillus paracasei/crescimento & desenvolvimento , Lactobacillus plantarum/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento
19.
Handb Exp Pharmacol ; 256: 137-165, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31201554

RESUMO

In the recent years, bile acid receptors FXR and GPBAR1 have attracted the interest of scientific community and companies, as they proved promising targets for the treatment of several diseases, ranging from liver cholestatic disorders to metabolic syndrome, inflammatory states, nonalcoholic steatohepatitis (NASH), and diabetes.Consequently, the development of dual FXR/GPBAR1 agonists, as well as selective targeting of one of these receptors, is considered a hopeful possibility in the treatment of these disorders. Because endogenous bile acids and steroidal ligands, which cover the same chemical space of bile acids, often target both receptor families, speculation on nonsteroidal ligands represents a promising and innovative strategy to selectively target GPBAR1 or FXR.In this review, we summarize the most recent acquisition on natural, semisynthetic, and synthetic steroidal and nonsteroidal ligands, able to interact with FXR and GPBAR1.


Assuntos
Ácidos e Sais Biliares/química , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Acoplados a Proteínas-G/agonistas , Receptores Acoplados a Proteínas-G/antagonistas & inibidores , Ácidos e Sais Biliares/farmacologia , Humanos , Ligantes
20.
Handb Exp Pharmacol ; 256: 3-18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31201555

RESUMO

This review provides a historical perspective of bile acids and their receptors as therapeutic targets. Bile acids are atypical steroids generated by the liver from cholesterol and have been used for almost half a century for treating liver and biliary disorders. Since the early 1970s of the last century, chenodeoxycholic acid (CDCA), a primary bile acid, and ursodeoxycholic acid (UDCA), a secondary bile acid and the 7ßepimer of CDCA, have been shown effective in promoting the dissolution of cholesterol gallstones. However, lack of activity and side effects associated with the use of CDCA, along with the advent of laparoscopic cholecystectomy, have greatly reduced the clinical relevance of this application. At the turn of the century, however, the discovery that bile acids activate specific receptors, along with the discovery that those receptors are placed at the interface of the host and intestinal microbiota regulating physiologically relevant enterohepatic and entero-pancreatic axes, has led to a "bile acid renaissance." Similarly to other steroids, bile acids bind and activate both cell surface and nuclear receptors, including the bile acid sensor farnesoid X receptor (FXR) and a G-protein-coupled bile acid receptor, known as GPBAR1 (TGR5). Both receptors have been proved druggable, and several highly potent, selective, and nonselective ligands for the two receptors have been discovered in the last two decades. Currently, in addition to obeticholic acid, a semisynthetic derivative of CDCA and the first in class of FXR ligands approved for clinical use, either selective or dual FXR and GPBAR1 ligands, have been developed, and some of them are undergoing pre-approval trials. The effects of FXR and GPBAR1 ligands in different therapeutic area are reviewed.


Assuntos
Ácidos e Sais Biliares/farmacologia , Receptores Citoplasmáticos e Nucleares/farmacologia , Humanos , Ligantes , Fígado , Receptores Acoplados a Proteínas-G
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