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1.
BMC Med Educ ; 23(1): 118, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36803351

RESUMO

BACKGROUND: The purpose of this article is to discuss the statistical methods for agreement analysis used in Richelle's article (BMC Med Educ 22:335, 2022). The authors investigated the attitudes of final-year medical students regarding substance use during pregnancy and identified the factors that influence these attitudes. METHODS: We found that Cohen's kappa value for measuring the agreement between these medical students' attitudes towards drugs/alcohol use during pregnancy was questionable. In addition, we recommend using weighted kappa instead of Cohen's kappa for agreement analysis at the presence of three categories. RESULTS: The agreement improved from "good" (Cohen's kappa) to "very good" (weighted kappa) for medical students' attitudes towards drugs/alcohol use during pregnancy. CONCLUSION: To conclude, we recognize that this does not significantly alter the conclusions of the Richelle et al. paper, but it is necessary to ensure that the appropriate statistical tools are used.


Assuntos
Estudantes de Medicina , Transtornos Relacionados ao Uso de Substâncias , Humanos , Gravidez , Feminino , Reprodutibilidade dos Testes
2.
Future Microbiol ; 18: 137-157, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36688318

RESUMO

Helicobacter pylori, a Gram-negative microaerobic bacteria belonging to the phylum Proteobacteria, can colonize in the stomach and duodenum, and cause a series of gastrointestinal diseases such as gastritis, gastric ulcer and even gastric cancer. At present, the high diversity of the microorganisms in the stomach has been confirmed with culture-independent methods; some researchers have also studied the stomach microbiota composition at different stages of H. pylori carcinogenesis. Here, we mainly review the possible role of H. pylori-mediated microbiota changes in the occurrence and development of gastric cancer to provide new ideas for preventing H. pylori infection and regulating microecological imbalance.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Microbiota , Neoplasias Gástricas , Humanos , Helicobacter pylori/genética , Neoplasias Gástricas/microbiologia , Infecções por Helicobacter/microbiologia , Homeostase
3.
Acta Biochim Biophys Sin (Shanghai) ; 55(1): 143-153, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36647727

RESUMO

Krüppel-like factor 7 (KLF7) is a negative regulator of preadipocyte differentiation. Our previous KLF7 ChIP-seq analysis showed that the binding motif of PU.1 was found among the KLF7 binding peaks, indicating that an interaction between KLF7 and PU.1 at preadipocyte gene promoters and other regulatory elements might be common. Here, Co-IP and FRET assays are used to confirm that PU.1 can directly bind to KLF7 and enhance the transcription activity of cyclin-dependent kinase inhibitor 3 ( CDKN3), which is a downstream target gene of KLF7. We show that the PU.1 expression level is decreased during preadipocyte differentiation. Furthermore, PU.1 overexpression and knockdown experiments reveal that PU.1 negatively regulates chicken preadipocyte differentiation, as evidenced by appropriate changes in lipid droplet accumulation and altered expressions of PPARγ, FAS, and PLIN. In addition, PU.1 overexpression promotes preadipocyte proliferation, while knockdown of PU. 1 inhibits preadipocyte proliferation. We further demonstrate that PU.1 inhibits differentiation and promotes proliferation in preadipocytes, in part by directly interacting with KLF7.


Assuntos
Galinhas , Fatores de Transcrição Kruppel-Like , Animais , Diferenciação Celular , Proliferação de Células/fisiologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo
4.
Mol Biol Rep ; 50(2): 1517-1531, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36509909

RESUMO

BACKGROUND: Gastric cancer is heterogeneous cancer and the causes of this disease are complex. New diagnostic and therapeutic targets are urgently needed to explore. Huntingtin-associated protein 1 (HAP1) is directly related to Huntington's disease (HD). However, patients with Huntington's disease have a lower incidence of cancer. Therefore, we are committed to studying the correlation between HAP1 and gastric carcinogenesis and development. METHODS AND RESULTS: Immunohistochemical staining, western blot analysis, and RT-qPCR were conducted to explore the localization and expression of HAP1 in gastric cancer. To study the biological significance of HAP1, we overexpressed HAP1 in both MKN28 and AGS cell lines by lentivirus infection. To explore the role of HAP1 in cell proliferation, the cells counting assay, EdU incorporation assay, and colony formation assay were carried out. We performed the wound healing assay and transwell assay to study the cell migration and invasion. To further investigate whether HAP1 could regulate gastric cancer cell death during glucose deprivation, Annexin V-FITC/PI staining was performed. In our study, we elucidated that HAP1 was downregulated in gastric cancer. What's more, overexpressing HAP1 inhibited cell proliferation, cell migration and invasion, and triggered apoptosis during glucose deprivation. More importantly, the antitumor properties and mechanisms of HAP1 have been elucidated further in gastric cancer. CONCLUSIONS: Taken together, the available evidence implies that HAP1 may serve as a potential tumor suppressor, making it a significant target in preventing and treating gastric cancer. This research provides a theoretical basis for the early diagnosis, clinical targeted therapy, and prognosis evaluation of gastric cancer.


Assuntos
Doença de Huntington , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Proteínas do Tecido Nervoso/metabolismo , Doença de Huntington/metabolismo , Apoptose/genética , Morte Celular , Proliferação de Células/genética , Linhagem Celular Tumoral
5.
Biochim Biophys Acta Gene Regul Mech ; 1866(1): 194899, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36410687

RESUMO

Krüppel-like factor 7 (KLF7) negatively regulates adipocyte differentiation; however, the mechanism underlying its activity in mammals and birds remains poorly understood. To identify genome-wide KLF7-binding motifs in preadipocytes, we conducted a chromatin immunoprecipitation-sequencing analysis of immortalized chicken preadipocytes (ICP2), which revealed 11,063 specific binding sites. Intergenic binding site analysis showed that KLF7 regulates several novel factors whose functions in chicken and mammal adipogenesis are underexplored. We identified a novel regulator, troponin I2 (TNNI2), which is positively regulated by KLF7. TNNI2 is downregulated during preadipocyte differentiation and acts as an adipogenic repressor at least in part by repressing FABP4 promoter activity. In conclusion, we demonstrated that KLF7 functions through cis-regulation of TNNI2, which inhibits adipogenesis. Our findings not only provide the first genome-wide picture of KLF7 associations in preadipocytes but also identify a novel function of TNNI2.


Assuntos
Galinhas , Troponina I , Animais , Adipogenia/genética , Galinhas/genética , Galinhas/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Mamíferos/metabolismo , Regiões Promotoras Genéticas , Troponina I/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo
6.
Mol Biol Rep ; 50(1): 889-897, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36367659

RESUMO

Helicobacter pylori (H. pylori) is a common pathogen that infects more than half of the world's population. Its infection can not only lead to a variety of gastrointestinal diseases, such as chronic gastritis and gastric cancer (GC) but also be associated with many extra-gastrointestinal diseases. Exosomes, as a new intercellular information transmission medium, can carry biological signal molecules such as microRNAs (miRNAs) to regulate a variety of cellular physiological activities and are involved in multiple cancer processes. In this article, we provide a systematic review on the role of exosomal miRNAs in H. pylori-associated GC.


Assuntos
Exossomos , Infecções por Helicobacter , MicroRNAs , Neoplasias Gástricas , Humanos , Exossomos/genética , Mucosa Gástrica , Infecções por Helicobacter/genética , Infecções por Helicobacter/complicações , Helicobacter pylori , MicroRNAs/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiologia
7.
China Tropical Medicine ; (12): 439-2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-979706

RESUMO

@#Abstract: Objective  This article aims to present a rare case of severe fever with thrombocytopenia syndrome (SFTS) complicated by with bacteraemia caused by Campylobacter jejuni, and to discuss the pathogenic characteristics, culture methods, clinical features and treatment points of Campylobacter jejuni and the patient's outcome, with a view to raising clinical awareness of blood culture and providing experience for the treatment of this disease. Methods The clinical data of a case with SFTS complicated by bacteremia caused by Campylobacter jejuni admitted to Weihai Municipal Hospital were collected and the diagnostic process of the pathogenic bacteria as well as the treatment plan were retrospectively analysed. Results The patient was a female who had been bitten by a tick bite half a month ago and presented to the hospital on 30th August with a fever, vague pain in the peribulbar abdomen and diarrhea for 5 days. Laboratory tests showed leukopenia and thrombocytopenia, and nucleic acid detection for SFTS was positive, resulting in a diagnosis of SFTS. After a week of antiviral treatment with ribavirin and symptomatic treatment, the patient suddenly experienced high fever at night, with a temperature reaching 39.5 °C. Blood cultures were immediately taken from both sides of the double bottle. Bilateral anaerobic bottles were tested for positive after 53.06 hours, and Gram-negative Campylobacter was cultured anaerobically in a transfer blood plate and further identified as Campylobacter jejuni using mass spectrometry MALDI-TOF MS. Vancomycin was stopped clinically on the basis of bacterial pathogenesis and meropenem was used for anti-infection and symptomatic treatment. During the treatment, blood culture and nucleic acid detection for SFTS turned negative, and the patient's symptoms improved. After normal results were achieved in the follow-up testing, the patient was discharged. Conclusions This case serves as a reminder that Campylobacter jejuni not only causes intestinal infections, but can also lead to extra-intestinal infections in immunocompromised individuals. Clinical and laboratory personnel should increase their recognition of Campylobacter jejuni, prioritize blood culture methods, and utilize a multidisciplinary approach in diagnosis and treatment.

9.
Acta Biochim Biophys Sin (Shanghai) ; 54(10): 1486-1496, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36269137

RESUMO

Krüppel-like transcription factor 7 (KLF7) promotes preadipocyte proliferation; however, its target gene in this process has not yet been identified. Using KLF7 ChIP-seq analysis, we previously showed that a KLF7-binding peak is present upstream of the cyclin-dependent kinase inhibitor 3 gene ( CDKN3) in chicken preadipocytes. In the present study, we identify CDKN3 as a target gene of KLF7 that mediates the effects of KLF7 on preadipocyte proliferation. Furthermore, 5'-truncating mutation analysis shows that the minimal promoter is located between nt -160 and nt -7 (relative to the translation initiation codon ATG) of CDKN3. KLF7 overexpression increases CDKN3 promoter activity in the DF-1 and immortalized chicken preadipocyte (ICP1) cell lines. Deletion of the putative binding site of KLF7 abolishes the promotive effect of KLF7 overexpression on CDKN3 promoter activity. Moreover, CDKN3 knockdown and overexpression assays reveal that CDKN3 enhances ICP1 cell proliferation. Flow cytometry analysis shows that CDKN3 accelerates the G1/S transition. Furthermore, we find that KLF7 promotes ICP1 cell proliferation via Akt phosphorylation by regulating CDKN3. Taken together, our results suggest that KLF7 promotes preadipocyte proliferation by activating the Akt signaling pathway by cis-regulating CDKN3, thus driving the G1/S transition.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Transdução de Sinais/fisiologia , Proliferação de Células/genética , Linhagem Celular , Fatores de Transcrição Kruppel-Like/genética
10.
Mol Med Rep ; 26(4)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36043523

RESUMO

Cytidine triphosphate synthase (CTPS) forms filamentous structures termed cytoophidia in numerous types of cell. Toosendanin (TSN) is a tetracyclic triterpenoid and induces CTPS to form cytoophidia in MKN45 cells. However, the effects of CTPS cytoophidia on the proliferation and apoptosis of human gastric cancer cells remain poorly understood. In the present study, CTPS­overexpression and R294D­CTPS mutant vectors were generated to assess the effect of CTPS cytoophidia on the proliferation and apoptosis of gastric cancer MKN45 cells. Formation of CTPS cytoophidia significantly inhibited MKN45 cell proliferation (evaluated using EdU incorporation assay), significantly blocked the cell cycle in G1 phase (assessed using flow cytometry) and significantly decreased mRNA and protein expression levels of cyclin D1 (assessed by reverse transcription­quantitative PCR and western blotting, respectively). Furthermore, the number of apoptotic bodies and apoptosis rate were markedly elevated and mitochondrial membrane potential was markedly decreased. Moreover, mRNA and protein expression levels of Bax increased and Bcl­2 decreased markedly in MKN45 cells following transfection with the CTPS­overexpression vector. The proliferation rate increased, percentage of G1/G0­phase cells decreased and apoptosis was attenuated in cells transfected with the R294D­CTPS mutant vector and this mutation did not lead to formation of cytoophidia. The results of the present study suggested that formation of CTPS cytoophidia inhibited proliferation and promoted apoptosis in MKN45 cells. These results may provide insights into the role of CTPS cytoophidia in cancer cell proliferation and apoptosis.


Assuntos
Neoplasias Gástricas , Humanos , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Citidina Trifosfato/metabolismo , RNA Mensageiro , Neoplasias Gástricas/genética , Triterpenos
11.
Front Bioeng Biotechnol ; 10: 936914, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795165

RESUMO

The human gut microbiota play essential roles in metabolism and human health, especially by enzymatically utilizing dietary fiber that the host cannot directly digest and releasing functional components including short-chain fatty acids (SCFAs) and hydroxycinnamic acids (e.g., ferulic acid). In our previous study, seven potential feruloyl esterase (FAE) genes were identified from the gut microbiota. In the current work, one of the genes encoding a novel FAE (DfFAE) from Dorea formicigenerans of Firmicutes was bacterially expressed, purified and characterized. The 30.5 kDa type-A DfFAE has an optimum pH and temperature of 8.4 and 40 °C, respectively, exhibiting a higher substrate specificity toward short-chain acyl-ester substrate (pNPA). The AlphaFold2 based ab initio structural modeling revealed a five α-helices cap domain that shaped an unusually narrow and deep active site pocket containing a specific substrate access tunnel in DfFAE. Furthermore, rational design strategy was subjected to the active site pocket in an aim of improving its enzymatic activities. The mutants V252A, N156A, W255A, P149A, and P186A showed 1.8 to 5.7-fold increase in catalytic efficiency toward pNPA, while W255A also exhibited altered substrate preference toward long-chain substrate pNPO (45.5-fold). This study highlighted an unusual active site architecture in DfFAE that influenced its substrate selectivity and illustrated the applicability of rational design for enhanced enzymatic properties.

12.
Proc Natl Acad Sci U S A ; 119(20): e2111051119, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35537054

RESUMO

Exocytosis and endocytosis are tightly coupled. In addition to initiating exocytosis, Ca2+ plays critical roles in exocytosis­endocytosis coupling in neurons and nonneuronal cells. Both positive and negative roles of Ca2+ in endocytosis have been reported; however, Ca2+ inhibition in endocytosis remains debatable with unknown mechanisms. Here, we show that synaptotagmin-1 (Syt1), the primary Ca2+ sensor initiating exocytosis, plays bidirectional and opposite roles in exocytosis­endocytosis coupling by promoting slow, small-sized clathrin-mediated endocytosis but inhibiting fast, large-sized bulk endocytosis. Ca2+-binding ability is required for Syt1 to regulate both types of endocytic pathways, the disruption of which leads to inefficient vesicle recycling under mild stimulation and excessive membrane retrieval following intense stimulation. Ca2+-dependent membrane tubulation may explain the opposite endocytic roles of Syt1 and provides a general membrane-remodeling working model for endocytosis determination. Thus, Syt1 is a primary bidirectional Ca2+ sensor facilitating clathrin-mediated endocytosis but clamping bulk endocytosis, probably by manipulating membrane curvature to ensure both efficient and precise coupling of endocytosis to exocytosis.


Assuntos
Endocitose , Transmissão Sináptica , Sinaptotagmina I , Cálcio/metabolismo , Endocitose/fisiologia , Exocitose/fisiologia , Neurônios/metabolismo , Sinaptotagmina I/metabolismo
13.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(5): 590-594, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-37088775

RESUMO

OBJECTIVE: To investigate the effects of down-regulating MDR1 gene expression by CRISPRi on enhancing the sensitivity of lung adenocarcinoma A549/DDP cells to cisplatin. METHODS: The potential CRISPRi interference sites on the MDR1 gene promoter were predicted by bioinformatics software, and the interference fragments were designed and constructed. The mRNA and protein expression levels of MDR1 gene in each group of cells were detected by qRT-PCR and Western blot methods, and the recombinant vectors with high interference efficiency were screened. Human lung cancer A549/DDP cells were divided into three groups: A549/DDP, Scrambed and sgRNA-MDR1-1, with three multiple holes in each group. After each vector was transfected into the cells for 48 h, the efflux of cells in each group was detected by flow cytometry, the IC50 value of cells in each group was detected by MTT method, and the cell morphology of cells treated with cisplatin was observed under laser confocal microscope. RESULTS: After sequencing and comparison, two kinds of CRISPRi recombinant vectors interfering with MDR1 gene transcription were constructed successfully. After transfection of A549/DDP cells, the mRNA and protein levels of MDR1 gene in all transfection groups were decreased significantly (P< 0.01). Among them, the interference efficiency of sgRNA-MDR1-1 was the highest, and the interference efficiency of mRNA and protein was 60% and 51%, respectively. After transfection of sgRNA-MDR1-1 vector, compared with the control group, the efflux ability of cells was decreased (P<0.01), the IC50 value of cells to cisplatin was decreased significantly (P<0.01), and the intracellular chromatin gathered and marginalized, and apoptotic bodies appeared. CONCLUSION: CRISPRi interference with MDR1 gene in drug-resistant A549/DDP cells can significantly enhance the sensitivity to cisplatin.


Assuntos
Adenocarcinoma de Pulmão , Antineoplásicos , Neoplasias Pulmonares , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Antineoplásicos/farmacologia , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Apoptose , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , RNA Mensageiro , Expressão Gênica
14.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(6): 622-627, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-37308406

RESUMO

Objective: To investigate the effect of SIX2 gene on the proliferation of bovine skeletal muscle satellite cells. Methods: Bovine skeletal muscle satellite cells were used as experimental materials, and the expression of SIX2 gene in bovine skeletal muscle satellite cells was detected by real-time quantitative PCR at 24 h, 48 h, and 72 h of proliferation. The SIX2 gene overexpression vector was constructed by homologous recombination. The SIX2 gene overexpression plasmid and the control empty plasmid were transfected into bovine skeletal muscle satellite cells, and each group had three complex Wells. The cell viability was detected by MTT assay at 24 h, 48 h and 72 h after transfection. At 48 h after transfection, the cell cycle was detected by flow cytometry, and the expressions of cell proliferation marker genes were detected by real-time quantitative PCR (qRT-PCR) and Western blot. Results: With the proliferation of bovine skeletal muscle satellite cells, the expression of SIX2 mRNA was increased. Compared with the control group, the expressions of SIX2 mRNA and protein in the SIX2 gene overexpression plasmid group were increased by 18 and 2.6 times, respectively (P<0.01). The cell viability of the SIX2 gene overexpression plasmid group was increased (P<0.01), the proportion of G1 cells was decreased by 24.6%, and the proportion of S phase and G2 phase cells was increased by 20.3% and 4.31%, respectively (P<0.01). The mRNA and protein expressions of Pax7 gene were increased by 15.84 and 1.22 times, respectively, and the mRNA and protein expressions of proliferation marker genes PCNA and CCNB1 were increased by 4.82, 2.23,1.55 and 1.46 times, respectively (P<0.01). Conclusion: Overexpression of SIX2 gene promotes the proliferation of bovine skeletal muscle satellite cells.


Assuntos
Células Satélites de Músculo Esquelético , Bovinos , Animais , Ciclo Celular , Proliferação de Células , RNA Mensageiro , Fatores de Transcrição
15.
Arch Anim Nutr ; 76(3-6): 205-220, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36645054

RESUMO

Corn peptide (CP) is a small, natural, biologically active peptide obtained by protease-catalysed hydrolysis of corn. CP exerts antihypertensive, hypoglycaemic, antihyperlipidemic, antioxidant, and antitumor effects, as well as prevents cardiovascular and cerebrovascular diseases. Although CP plays a role in preventing obesity-related diseases, its role in reducing obesity has not yet been determined. In this study, we analysed the inhibitory effects of CP on lipid droplet accumulation in 3T3-L1 preadipocytes and high-fat diet (HFD)-induced C57BL/6J Obese Mice. The results show that CP could inhibit preadipocyte differentiation and oil accumulation in 3T3-L1 preadipocytes. Oral CP administration reduced serum triglyceride (TG) content, epididymal fat weight, abnormal liver fat droplet accumulation, and C/EBPα expression. Furthermore, combination of CP administration and exercise reduced body, liver, and adipose tissue weights; decreased serum total cholesterol (TC), triglyceride and low-density lipoprotein (LDL) levels; and inhibited hepatic lipid droplet accumulations and epididymal fat cell hypertrophy. Additionally, this combination inhibited the expression of transcription factors, C/EBPα, C/EBPß, and PPARγ, and adipogenic factors, FABP4 in mice. In conclusion, oral administration of CP inhibited lipid droplet accumulation and counteracted HFD-induced obesity in mice.


Assuntos
Fármacos Antiobesidade , Obesidade , Doenças dos Roedores , Camundongos , Animais , Camundongos Obesos , Zea mays , Fármacos Antiobesidade/metabolismo , Fármacos Antiobesidade/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Adipócitos/patologia , Camundongos Endogâmicos C57BL , Ração Animal/análise , Obesidade/metabolismo , Obesidade/prevenção & controle , Obesidade/veterinária , Triglicerídeos/metabolismo , Triglicerídeos/farmacologia , Dieta Hiperlipídica , Peptídeos/metabolismo , Peptídeos/farmacologia , Doenças dos Roedores/metabolismo , Doenças dos Roedores/patologia
16.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(5): 495-499, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34816660

RESUMO

Objective: To investigate the effects of betulinic acid on apoptosis of human gastric cancer SGC-7901 cells. Methods: The human gastric cancer SGC-7901cells were divided in to 4 groups, and each group was set with 3 replicates. The SGC-7901cells in control group were not treated with betulinic acid; the other 3 experimental groups were treated with betulinic acid at the concentrations of 10, 20 and 30 mg/L, respectively; each group was incubated in a 5% carbon dioxide incubator for 48 h. Laser confocal microscope was used to observe morphological changes of SGC-7901 cells; Flow cytometry was applied to determine apoptosis rate and mitochondrial membrane potential. The mRNA and protein levels of Bcl-2, Bax and Caspase-3 were also detected by qRT-PCR and western blot respectively. Results: Compared with the control group, SGC-7901 cells in the treated group at final concentrations of 10, 20 and 30 mg/L shrinked, appeared apoptosis body along with nuclear splitting. The percentage of cells in early and advanced period of apoptosis were markedly increased (P<0.05 or P<0.01), mitochondrial membrane potential was obviously reduced (P<0.05 or P<0.01). qRT-PCR and western blot analysis showed that the mRNA and protein expressions of Bax and Caspase-3 were increased significantly (P<0.01), while the expressions of Bcl-2 were decreased significantly (P<0.01). Conclusion: Within a certain range of concentrations, betulinic acid induces cell apoptosis by regulating the expression of Bcl-2, Bax and Caspase-3 in human gastric cancer.


Assuntos
Apoptose/efeitos dos fármacos , Triterpenos Pentacíclicos/farmacologia , Neoplasias Gástricas , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Gástricas/patologia , Ácido Betulínico
17.
J Agric Food Chem ; 69(23): 6665-6675, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34074097

RESUMO

Gut bacteria-derived enzymes play important roles in the metabolism of dietary fiber through enabling the hydrolysis of polysaccharides. In this study, we identified and characterized a 29 kDa novel acetyl xylan esterase, BTAxe1, from Bacteroides thetaiotaomicron VPI5482. Then, we solved the structure of BTAxe1 and performed the rational design. Mutants N65S and N65A increased the activities toward short-chain (pNPA, pNPB) to near four-fold, and gained the activities toward longer-chain substrate (pNPO). Molecular docking analysis showed that the mutant N65S had a larger substrate binding pocket than the wild type. Hydrolysis studies using natural substrates showed that either N65S or N65A showed higher activity of that of wild-type, yielding 131.31 and 136.09 mM of acetic acid from xylan. This is the first study on the rational design of gut bacteria-derived Axes with broadened substrate specificity and enhanced activity, which can be referenced by other acetyl esterases or gut-derived enzymes.


Assuntos
Bacteroides thetaiotaomicron , Acetilesterase/genética , Acetilesterase/metabolismo , Bacteroides thetaiotaomicron/genética , Simulação de Acoplamento Molecular , Especificidade por Substrato
18.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(2): 171-175, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32744014

RESUMO

Objective: To investigate the effects of hedyotis diffusa (injection) on mitochondrial membrane potential and expressions of apoptosis-related genes in human gastric cancer cell line MNK-45 cells. Methods: The human gastric cancer MNK-45 cells were divided into 4 groups, each group was set with 3 replicates. The control group was MNK-45 cells without added hedyotis diffusa; the 3 groups of experimental groups were treated with hedyotis diffusa at final concentrations of 20 , 30, 40 µg / ml respectively; each group was incubated for 48 h in a 5% carbon dioxide incubator, and the morphological changes of the cells were observed under a laser confocal microscope. Mitochondrial membrane potential was detected by flow cytometry. The expressions of Cytochrome C (Cyt c), caspase3 and caspase9 genes and proteins were detected by qRT-PCR and Western blot respectively. Results: Compared with the control group, the mitochondrial membrane potentials of MNK-45 cells were significantly reduced in the hedyotis diffusa treated groups at final concentrations of 20, 30, and 40 µg / ml (P<0. 01). The gene expressions of Cyt c, caspase3, and caspase9 were significantly up-regulated (P<0. 01) and their protein expressions were also significantly increased (P<0. 05 or P<0. 01). The 40 µg / ml hedyotis diffusa treatment group performed best. Conclusion: In the final concentration range of 20 ~ 40 µg / ml, hedyotis diffusa can reduce human gastric cancer MNK-45 cells mitochondrial membrane potential, induce apoptosis and up-regulate Cyt c, caspase3 and caspase9 gene expressions.


Assuntos
Apoptose , Hedyotis/química , Potencial da Membrana Mitocondrial , Preparações de Plantas/farmacologia , Neoplasias Gástricas , Caspase 3 , Caspase 9 , Linhagem Celular Tumoral , Citocromos c/metabolismo , Humanos , Neoplasias Gástricas/genética
19.
Mol Med Rep ; 22(3): 1793-1802, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32582989

RESUMO

Toosendanin (TSN) is a tetracyclic triterpenoid extracted from Melia toosendan Sieb, et Zucc, which primarily grows in specific areas of China. Although toosendanin (TSN) exerts antitumoral effects on various human cancer cells, its influence on gastric cancer (GC) is remains to be elucidated. MicroRNAs (miRNAs/miRs) serve crucial roles in apoptosis and proliferation of cancer cells. miR­23a­3p has been shown to be associated with human GC; however, the specific function of miR­23a­3p in GC remains unclear. Therefore, the present study aimed to elucidate the role of miR­23a­3p in the regulation of GC cell proliferation and apoptosis induced in vitro by TSN treatment. Subsequently, apoptosis­related genes expression levels were quantified by reverse transcription­quantitative PCR and western blot analysis, respectively, and the target relationship between miR­23a­3p and BCL2 was determined by luciferase reporter gene analysis. Additionally, cell proliferation and apoptosis experiments were carried out. The results indicated that TSN inhibited proliferation and induced apoptosis in MKN­45 cells. Moreover, it upregulated the expression of miR­23a­3p. B­cell lymphoma­2 (BCL2) was identified as a potential target gene of miR­23a­3p, which was demonstrated to bind to the 3'­untranslated region of BCL2 mRNA, as detected by the luciferase reporter assay. Further studies revealed that BCL2 expression was downregulated following overexpression of miR­23a­3p. In addition, the overexpression of the miR­23a­3p inhibited proliferation, induced G1 arrest and increased apoptosis in MKN­45 cells. The results of the present study demonstrated that miR­23a­3p inhibited proliferation and induced apoptosis of GC cells, which may be attributable to its direct targeting of BCL2. These results may provide a novel insight into the apoptosis of GC cells, and may lead to investigations into the mechanisms of the effects of TSN.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Neoplasias Gástricas/genética , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Gástricas/tratamento farmacológico
20.
Front Physiol ; 11: 610, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32587528

RESUMO

Kruppel-like transcription factor 7 (KLF7) is a negative regulator of adipogenesis, however, its precise mechanism is poorly understood. Our previous KLF7 ChIP-seq analysis showed that one of the KLF7 binding peaks was present upstream of GATA binding protein 3 (GATA3) in chicken preadipocytes. In the present study, we identified GATA3 as a target of KLF7. Overexpression analysis showed KLF7 markedly enhanced the endogenous expression of GATA3 in the immortalized chicken preadipcyte cell line (ICP2), and the luciferase reporter assay showed that KLF7 overexpression increased the reporter gene activity of the cloned upstream region (-5285/-4336 relative to the translation initiation codon ATG) of GATA3 in ICP2 and DF1 cells, and mutation of the putative KLF7 binding site abolished the promotive effect of KLF7 overexpression on the reporter gene activity of the cloned GATA3 upstream region. ChIP-qPCR further demonstrated that KLF7 directly bound to the GATA3 upstream region. Gene expression analysis showed that GATA3 mRNA expression in abdominal adipose tissue was significantly higher in lean chicken line than in the fat line at 2, 3, and 6 weeks of age. In addition, GATA3 mRNA expression markedly decreased during the preadipocyte differentiation. Furthermore, a functional study showed that GATA3 overexpression inhibited the differentiation of the ICP2 cells. Taken together, our results demonstrated that KLF7 inhibits chicken adipogenesis, at least in part through direct upregulation of GATA3.

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