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1.
J Cancer ; 15(5): 1462-1486, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38356723

RESUMO

Tumor metastasis is a key factor affecting the life of patients with malignant tumors. For the past hundred years, scientists have focused on how to kill cancer cells and inhibit their metastasis in vivo, but few breakthroughs have been made. Here we hypothesized a novel mode for cancer metastasis. We show that the phagocytosis of apoptotic tumor cells by macrophages leads to their polarization into the M2 phenotype, and that the expression of stem cell related as well as drug resistance related genes was induced. Therefore, it appears that M2 macrophages have "defected" and have been transformed into the initial "metastatic cancer cells", and thus are the source, at least in part, of the distal tissue tumor metastasis. This assumption is supported by the presence of fused cells with characteristics of both macrophage and tumor cell observed in the peripheral blood and ascites of patients with ovarian cancer. By eliminating the expression of CD206 in M2 macrophages using siRNA, we show that the growth and metastasis of tumors was suppressed using both in vitro cell line and with experimental in vivo mouse models. In summary, we show that M2 macrophages in the blood circulation underwent a "change of loyalty" to become "cancer cells" that transformed into distal tissue metastasis, which could be suppressed by the knockdown of CD206 expression.

2.
Appl Environ Microbiol ; 89(9): e0097423, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37681961

RESUMO

Tolerance to acid stress is a crucial property of probiotics against gastric acids. The malolactic enzyme pathway is one of the most important acid resistance systems in lactic acid bacteria. It has been reported that the malolactic enzyme pathway was regulated by the transcriptional regulator, MleR. However, regulatory mechanisms underlying malolactic enzyme pathway to cope with acid stress remain unknown. In this study, the acid tolerance ability of the ΔmleR deletion strain was significantly lower than that of the wild-type strain, and the complementation of the mleR gene into the ΔmleR strain restored the acid tolerance of the ΔmleR strain, indicating that MleR was involved in acid tolerance response of Lacticaseibacillus paracasei L9. Real-time quantitative PCR and transcriptional fusion experiments confirmed MleR-activated transcription of the mleST gene cluster. Furthermore, MleR was confirmed to directly bind to the promoter region of the mleST operon using ChIP assays and EMSAs. The transcription start site G of the mleST operon was located at position -198 relative to the start codon of the mleS gene. The region from -80 to -61 upstream of the transcription start site was determined to be essential for MleR binding. Moreover, L-malic acid acted as an effector for MleR to activate the transcription of the mleST operon in a dose-dependent manner. These results revealed the regulatory mechanism behind MleR-mediated activation of the malolactic enzyme pathway to enhance acid tolerance in Lc. paracasei L9. IMPORTANCE Lacticaseibacillus paracasei is extensively used as probiotics in human health and fermented dairy production. Following consumption, Lc. paracasei is exposed to a variety of physico-chemical stresses, such as low pH in the stomach and bile salts in the intestines. The high acidity of the stomach severely inhibits bacterial metabolism and growth. Therefore, the acid tolerance response is critical for Lc. paracasei to survive. It has been reported that the malolactic enzyme (MLE) pathway plays an important role for LAB to resist acid stress. However, the regulatory mechanism has not yet been investigated. In this study, we determined that the LysR-type regulator MleR positively regulated the MLE pathway to enhance acid tolerance by binding -80 to -61 upstream of the transcription start site of the mleST operon. Further, L-malic acid acts as a co-inducer for MleR transcriptional regulation. Our study provides novel insights into acid tolerance mechanisms in LAB.


Assuntos
Lacticaseibacillus paracasei , Humanos , Lacticaseibacillus , Ácidos
3.
Int J Mol Sci ; 24(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37175692

RESUMO

Mesonia algae K4-1 from the Arctic secretes a novel cold-adapted and salt-tolerant protease EK4-1. It has the highest sequence similarity with Stearolysin, an M4 family protease from Geobacillus stearothermophilus, with only 45% sequence identity, and is a novel M4 family protease. Ek4-1 has a low optimal catalytic temperature (40 °C) and is stable at low temperatures. Moreover, EK4-1 is still active in 4 mol/L NaCl solution and is tolerant to surfactants, oxidizing agents and organic solvents; furthermore, it prefers the hydrolysis of peptide bonds at the P1' position as the hydrophobic residues, such as Leu, Phe and Val, and amino acids with a long side chain, such as Phe and Tyr. Mn2+and Mg2+ significantly promoted enzyme activity, while Fe3+, Co+, Zn2+ and Cu2+ significantly inhibited enzyme activity. Amino acid composition analysis showed that EK4-1 had more small-side-chain amino acids and fewer large-side-chain amino acids. Compared with a thermophilic protease Stearolysin, the cold-adapted protease EK4-1 contains more random coils (48.07%) and a larger active pocket (727.42 Å3). In addition, the acidic amino acid content of protease EK4-1 was higher than that of the basic amino acid, which might be related to the salt tolerance of protease. Compared with the homologous proteases EB62 and E423, the cold-adapted protease EK4-1 was more efficient in the proteolysis of grass carp skin, salmon skin and casein at a low temperature, and produced a large number of antioxidant peptides, with DPPH, ·OH and ROO· scavenging activities. Therefore, cold-adapted and salt-tolerant protease EK4-1 offers wide application prospects in the cosmetic and detergent industries.


Assuntos
Endopeptidases , Peptídeo Hidrolases , Sequência de Aminoácidos , Aminoácidos , Especificidade por Substrato
4.
Microbiol Spectr ; : e0415022, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36877018

RESUMO

Capsular polysaccharide (CPS) can tightly attach to bacterial surfaces and plays a critical role in protecting microorganisms from environmental stresses. However, the molecular and functional properties of some plasmid-borne cps gene clusters are poorly understood. In this study, comparative genomics of the draft genomes of 21 Lactiplantibacillus plantarum strains revealed that the specific gene cluster for CPS biosynthesis was observed only in the 8 strains with a ropy phenotype. Furthermore, the complete genomes showed that the specific gene cluster cpsYC41 was located on the novel plasmid pYC41 in L. plantarum YC41. In silico analysis confirmed that the cpsYC41 gene cluster contained the dTDP-rhamnose precursor biosynthesis operon, the repeating-unit biosynthesis operon, and the wzx gene. The insertional inactivation of the rmlA and cpsC genes abolished the ropy phenotype and reduced the CPS yields by 93.79% and 96.62%, respectively, in L. plantarum YC41 mutants. These results revealed that the cpsYC41 gene cluster was responsible for CPS biosynthesis. Moreover, the survival rates of the YC41-rmlA- and YC41-cpsC- mutants under acid, NaCl, and H2O2 stresses were decreased by 56.47 to 93.67% compared to that of the control strain. Furthermore, the specific cps gene cluster was also confirmed to play a vital role in CPS biosynthesis in L. plantarum MC2, PG1, and YD2. These findings enhance our understanding of the genetic organization and gene functions of plasmid-borne cps gene clusters in L. plantarum. IMPORTANCE Capsular polysaccharide is well known to protect bacteria against various environmental stresses. The gene cluster for CPS biosynthesis is typically organized in the chromosome in bacteria. It is worth noting that complete genome sequencing showed that a novel plasmid pYC41-borne cpsYC41 gene cluster was identified in L. plantarum YC41. The cpsYC41 gene cluster included the dTDP-rhamnose precursor biosynthesis operon, the repeating-unit biosynthesis operon, and the wzx gene, which was verified by the significantly decreased CPS yield and the absent ropy phenotype in the corresponding mutants. The cpsYC41 gene cluster plays an important role in bacterial survival under environmental stress, and the mutants had decreased fitness under stress conditions. The vital role of this specific cps gene cluster in CPS biosynthesis was also confirmed in other CPS-producing L. plantarum strains. These results advanced a better understanding of the molecular mechanisms of plasmid-borne cps gene clusters and the protective functionality of CPS.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36569344

RESUMO

Retinal pericyte migration occurs in the early stage of diabetic retinopathy (DR), which is one of the important causes of pericyte loss. Autophagy has been found to play essential roles in the regulation of many types of cell migration. In this study, we explored the relationship between autophagy and retinal pericyte migration. In diabetic rats, the retinas became thinner, and the level of autophagy in each cell layer increased. In the primary culture of bovine retinal pericytes, we found that advanced glycation end products (AGEs) increased the migratory cell ability without influencing cell viability, which also increased the phosphorylation of focal adhesion kinase (FAK) and the expression of matrix metalloproteinase (MMP)-2 and decreased the expression of vinculin. AGEs-induced retinal pericyte autophagy and the inhibition of autophagy with chloroquine significantly inhibited cell migration, reversed AGEs-induced FAK phosphorylation, and changed vinculin and MMP-2 protein expression. These results provide a new insight into the migration mechanism of retinal pericytes. The early control of autophagy has a potential effect on regulating pericyte migration, which may contribute to keeping the integrity of retinal vessels in DR.

6.
J Agric Food Chem ; 70(29): 9007-9016, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35833866

RESUMO

Bile stress tolerance is a crucial characteristic of probiotics for surviving in the human gastrointestinal tract. The mechanism underlying the effect of l-malic acid on enhancing the glycodeoxycholic acid (GDCA) tolerance of Lacticaseibacillus paracasei L9 was investigated herein. Bile tolerance specificity assays revealed that Lc. paracasei L9 was more sensitive to GDCA than to taurocholic acid, glycocholic acid, and taurodeoxycholic acid. Notably, l-malic acid significantly enhanced the GDCA tolerance of Lc. paracasei L9 by increasing the pH of the medium. The role of the malolactic enzyme pathway in enhancing GDCA resistance was investigated using molecular techniques. Confocal laser scanning and scanning electron microscopy revealed that l-malic acid preserved membrane permeability and cellular morphology, thereby protecting bacterial cells from GDCA stress-induced damage. The study also demonstrated that l-malic acid enhanced bile tolerance in different species of lactobacilli. These findings provide a novel protective mechanism for coping with bile stress in lactobacilli.


Assuntos
Lacticaseibacillus paracasei , Probióticos , Ácido Glicodesoxicólico/farmacologia , Humanos , Lactobacillus , Malato Desidrogenase , Malatos
7.
Zhongguo Zhong Yao Za Zhi ; 47(6): 1433-1437, 2022 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-35347940

RESUMO

Panacis Quinquefolii Radix is the dry root of Panax quinquefolium, which is a perennial plant of Araliaceae. The plant has a long growth cycle and serious growth barrier problem, which leads to the use of pesticides. As a result, the pesticide residues in Panacis Quinquefolii Radix are arousing great concern. This paper reviews the research findings on the investigation, detection methods, content analysis and risk assessment of pesticide residues in Panacis Quinquefolii Radix since 1993, and compares the pesticide residue limit standards of different countries and regions. The pesticide residues in Panacis Quinquefolii Radix have been changing from organochlorines with high toxicity to triazines and triazoles with low toxicity. The pesticide residues are generally low, while the pollution of pentachloronitrobenzene and other pesticides still exist. The detection method has evolved from chromatography to chromatography-mass spectrometry. There are no reports of health risks caused by pesticide residues of Panacis Quinquefolii Radix. Pesticide residue is a major factor restricting the sound development of Panacis Quinquefolii Radix industry in China. Therefore, we suggest to improve the registration of pesticides applied to the plant, popularize mature ecological planting mode and supporting technology, and strengthen the research on the risk assessment and limit standard of pesticide residue in Panacis Quinquefolii Radix.


Assuntos
Medicamentos de Ervas Chinesas , Ginsenosídeos , Panax , Resíduos de Praguicidas , Medicamentos de Ervas Chinesas/química , Ginsenosídeos/análise , Espectrometria de Massas , Panax/química , Resíduos de Praguicidas/análise
8.
Rev Endocr Metab Disord ; 22(2): 205-216, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33761053

RESUMO

In diabetic patients, diabetic retinopathy (DR) is the leading cause of blindness and seriously affects the quality of life. However, current treatment methods of DR are not satisfactory. Advances have been made in understanding abnormal protein interactions and signaling pathways in DR pathology, but little is known about epigenetic regulation. Non-coding RNAs, such as circular RNAs (circRNAs), have been shown to be associated with DR. In this review, we summarized the function of circRNAs and indicated their roles in the pathogenesis of DR, which may provide new therapeutic targets for clinical treatment.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Retinopatia Diabética/genética , Epigênese Genética , Humanos , Qualidade de Vida , RNA Circular , Transdução de Sinais
9.
Food Chem ; 337: 127678, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32791429

RESUMO

The sequence and structure of antioxidant peptides play fundamental roles in their antioxidant functions. However, the structural mechanism of antioxidant peptides is still unclear. In this study, we used quantum calculations to reveal the antioxidant mechanism of the peptide PMRGGGGYHY. PMRGGGGYHY has multiple antioxidant active sites, and two tyrosine residues were determined to be the major active sites. Based on the structure-activity relationships of PMRGGGGYHY, the antioxidant activity of the modified peptide significantly improved by 4.8-fold to 9.73 ± 0.61 µmol TE/µmol. In addition, the removal of glycine residues from PMRGGGGYHY would increase the energy of the HOMOs and simplify the hydrogen bonding network, causing a significant increase in antioxidant activity. The intracellular ROS scavenging ability gradually decreased with decreasing glycine content. This same peptide has very different effects in vitro versus as a cellular antioxidant. This paper provides new insights into the structural mechanism and rational design/modification of novel antioxidant peptides.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Sequência de Aminoácidos , Relação Estrutura-Atividade
10.
PeerJ ; 8: e10060, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33150062

RESUMO

Despite recent great advances in microbial culture, most microbes have not yet been cultured, and the impact of medium composition on the isolation of microbes from natural systems has not been elucidated. To optimize media for culturing marine microbes, microbial communities in three sediment samples were described using high-throughput sequencing (HTS) and culture-dependent techniques. HTS revealed communities dominated by Gammaproteobacteria, and culture-based methods revealed communities dominated by Actinobacteria. Among the total operational taxonomic units (OTUs) from the HTS dataset, 6% were recovered in the culture collection. Four potentially novel bacterial strains belonging to Oceaniovalibus, Psychrobacter and Salegentibacter were isolated. The combination of media cultured more taxa than any single medium. Nutrient-rich and single-carbon/nitrogen-source media supported the growth of relatively few taxa, and the quality of nitrogen strongly influenced the types of bacteria isolated.

11.
Front Pharmacol ; 11: 589114, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33679385

RESUMO

GLP-1 analogs have been widely used to treat patients with type 2 diabetes in recent years and studies have found that GLP-1 analogs have multiple organ benefits. However, the role of GLP-1 analogs in diabetic retinopathy (DR), a common complication of diabetes mellitus (DM), remains controversial. Retinal ganglion cells (RGCs) are the only afferent neurons responsible for transmitting visual information to the visual center and are vulnerable in the early stage of DR. Protection of RGC is vital for visual function. The incretin glucagon-like peptide-1 (GLP-1), which is secreted by L-cells after food ingestion, could lower blood glucose level through stimulating the release of insulin. In the present study, we evaluated the effects of GLP-1 analog on RGCs both in vitro and in vivo. We established diabetic rat models in vivo and applied an RGC-5 cell line in vitro. The results showed that in high glucose conditions, GLP-1 analog alleviated the damage of RGCs. In addition, GLP-1 analog prevented mitophagy through the PINK1/Parkin pathway. Here we demonstrated the neuroprotective effect of GLP-1 analog, which may be beneficial for retinal function, and we further elucidated a novel mechanism in GLP-1 analog-regulated protection of the retina. These findings may expand the multi-organ benefits of GLP-1 analogs and provide new insights for the prevention of DR.

12.
Front Microbiol ; 10: 2812, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31866978

RESUMO

The special ecological environment of the Arctic has brought about a large number of salt-tolerant and psychrotolerant microorganisms. We isolated two culturable bacterial strains of the genus Mesonia; one from the Arctic ocean, Mesonia algae K4-1, and one from the tropical sea, Mesonia sp. HuA40. Our genome analysis and phenotypic experiments indicated that Mesonia algae K4-1 is a moderately halophilic and psychrophilic bacterium. Mesonia algae K4-1 can tolerate 3-14% NaCl and grow at a wide range of temperatures from 4 to 50°C. Mesonia sp. HuA40 is a mesophilic bacterium that can only grow with 3-9% NaCl. In addition, the salt adaptation strategy of Mesonia algae K4-1 accumulates organic osmolytes in the cell. RNA helicases, glutathione and organic compatible solutes may play important roles in maintaining the metabolism and physiological function of Mesonia algae K4-1 under cold stress. Moreover, the ability of Mesonia algae K4-1 to adapt to an oligotrophic marine environment is likely due to the synthesis of a large number of extracellular polysaccharides and the secretion of various families of extracellular proteases. This study systematically analyzed the relationship between genomic differentiation and environmental factors of the Mesonia genus and revealed the possible adaptation mechanism of Mesonia algae K4-1 in the extreme Arctic marine environment at the genomic level.

13.
Appl Environ Microbiol ; 85(14)2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31076429

RESUMO

The bacterial prepeptidase C-terminal (PPC) domain can be found in the C termini of a wide variety of proteases that are secreted by marine bacteria. However, the functions of these PPC domains remain unknown due to a lack of systematic research. Here, the binding and swelling abilities of eight PPC domains from six different proteases were compared systematically via scanning electron microscopy (SEM), enzyme assays, and fluorescence spectroscopy. These PPC domains all possess the ability to bind and swell insoluble collagen. PPC domains can expose collagen monomers but cannot disrupt the pyridinoline cross-links or unwind the collagen triple helix. This ability can play a synergistic role alongside collagenase in collagen hydrolysis. Site-directed mutagenesis of the PPC domain from Vibrio anguillarum showed that the conserved polar and aromatic residues Y6, D26, D28, Y30, W42, E53, C55, and Y65 and the hydrophobic residues V10, V18, and I57 played key roles in substrate binding. Molecular dynamic simulations were conducted to investigate the interactions between PPC domains and collagen. Most PPC domains have a similar mechanism for binding collagen, and the hydrophobic binding pocket of PPC domains may play an important role in collagen binding. This study sheds light on the substrate binding mechanisms of PPC domains and reveals a new function for the PPC domains of bacterial proteases in substrate degradation.IMPORTANCE Prepeptidase C-terminal (PPC) domains commonly exist in the C termini of marine bacterial proteases. Reports examining PPC have been limited, and its functions remain unclear. In this study, eight PPCs from six different bacteria were examined. Most of the PPCs possessed the ability to bind collagen, feathers, and chitin, and all PPCs could significantly swell insoluble collagen. PPCs can expose collagen monomers but cannot disrupt pyridinoline cross-links or unwind the collagen triple helix. This swelling ability may also play synergistic roles in collagen hydrolysis. Comparative structural analyses and the examination of PPC mutants revealed that the hydrophobic binding pockets of PPCs may play important roles in collagen binding. This study provides new insights into the functions and ecological significance of PPCs, and the molecular mechanism of the collagen binding of PPCs was clarified, which is beneficial for the protein engineering of highly active PPCs and collagenase in the pharmaceutical industry and of artificial biological materials.


Assuntos
Proteínas de Bactérias/metabolismo , Peptídeo Hidrolases/metabolismo , Domínios Proteicos , Ligação Proteica
14.
Molecules ; 23(6)2018 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-29861433

RESUMO

BACKGROUND: Pulmonary arterial hypertension (PAH) is characterized by increased pulmonary vascular resistance, leading to right ventricular failure and death. Recent studies have suggested that chronic inflammatory processes are involved in the pathogenesis of PAH. Several studies have demonstrated that betaine possesses outstanding anti-inflammatory effects. However, whether betaine exerts protective effects on PAH by inhibiting inflammatory responses in the lungs needs to be explored. To test our hypothesis, we aimed to investigate the effects of betaine on monocrotaline-induced PAH in rats and attempted to further clarify the possible mechanisms. METHODS: PAH was induced by monocrotaline (50 mg/kg) and oral administration of betaine (100, 200, and 400 mg/kg/day). The mean pulmonary arterial pressure, right ventricular systolic pressure, and right ventricle hypertrophy index were used to evaluate the development of PAH. Hematoxylin and eosin staining and Masson staining were performed to measure the extents of vascular remodeling and proliferation in fibrous tissue. Monocyte chemoattractant protein-1 (MCP-1) and endothelin-1 (ET-1) were also detected by immunohistochemical staining. Nuclear factor-κB (NF-κB), tumor necrosis factor alpha (TNF-α), and interleukin-1ß (IL-1ß) were assessed by Western blot. RESULTS: This study showed that betaine improved the abnormalities in right ventricular systolic pressure, mean pulmonary arterial pressure, right ventricle hypertrophy index, and pulmonary arterial remodeling induced by monocrotaline compared with the PAH group. The levels of MCP-1 and ET-1 also decreased. Western blot indicated that the protein expression levels of NF-κB, TNF-α, and IL-1ß significantly decreased (p < 0.01). CONCLUSION: Our study demonstrated that betaine attenuated PAH through its anti-inflammatory effects. Hence, the present data may offer novel targets and promising pharmacological perspectives for treating monocrotaline-induced PAH.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Betaína/farmacologia , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Monocrotalina/efeitos adversos , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/fisiopatologia , Animais , Biomarcadores , Quimiocina CCL2/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Endotelina-1/metabolismo , Hemodinâmica/efeitos dos fármacos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/metabolismo , Hipertrofia Ventricular Direita/tratamento farmacológico , Hipertrofia Ventricular Direita/etiologia , Hipertrofia Ventricular Direita/patologia , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , NF-kappa B/metabolismo , Ratos
15.
Peptides ; 105: 7-13, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29746877

RESUMO

Retinal pericyte migration represents a novel mechanism of pericyte loss in diabetic retinopathy (DR), which plays a crucial role in the early impairment of the blood-retinal barrier (BRB). Glucagon-like peptide-1 (GLP-1) has been shown to protect the diabetic retina in the early stage of DR; however, the relationship between GLP-1 and retinal pericytes has not been discussed. In this study, advanced glycation end products (AGEs) significantly increased the migration of primary bovine retinal pericytes without influencing cell viability. AGEs also significantly enhanced phosphatidylinositol 3-kinase (PI3K)/Akt activation, and changed the expressions of migration-related proteins, including phosphorylated focal adhesion kinase (p-FAK), matrix metalloproteinase (MMP)-2 and vinculin. PI3K inhibition significantly attenuated the AGEs-induced migration of retinal pericytes and reversed the overexpression of MMP-2. Glucagon-like peptide-1 receptor (Glp1r) was expressed in retinal pericytes, and liraglutide, a GLP-1 analog, significantly attenuated the migration of pericytes by Glp1r and reversed the changes in p-Akt/Akt, p-FAK/FAK, vinculin and MMP-2 levels induced by AGEs, indicating that the protective effect of liraglutide was associated with the PI3K/Akt pathway. These results provided new insights into the mechanism underlying retinal pericyte migration. The early use of liraglutide exerts a potential bebefical effect on regulating pericyte migration, which might contribute to mechanisms that maintain the integrity of vascular barrier and delay the development of DR.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Produtos Finais de Glicação Avançada/metabolismo , Pericitos/metabolismo , Retina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Barreira Hematorretiniana/metabolismo , Bovinos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Quinase 1 de Adesão Focal/metabolismo , Peptídeo 1 Semelhante ao Glucagon/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Liraglutida/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Pericitos/efeitos dos fármacos , Retina/patologia
16.
Br J Neurosurg ; 32(2): 141-148, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29357709

RESUMO

PURPOSE: Sodium fluorescein (SF) is an ideal dye for intraoperative guided-resection of high-grade gliomas (HGGs). However, it is not well understood whether the SF-guided technique is suitable for different grades of gliomas, and the correlation between fluorescence and pathology is also not yet clear. MATERIALS AND METHODS: In this study, we investigated 28 patients, including 23 patients with HGG and 5 patients with low-grade glioma (LGG). All patients were treated using the SF-guided technique on a Pentero 900 microscope (Carl Zeiss, Oberkochen, Germany). Claudin-5 immunohistochemical (IHC) staining for the tumours and peritumour tissues was analyzed. RESULTS: Intraoperative yellow fluorescence was noted in all the HGGs but not in the LGGs. Claudin-5 expression in the blood brain barrier endothelial cells was downregulated and disconnected in the HGGs (p < 0.05), but had no difference or slightly decreased in the LGGs (p > 0.05). CONCLUSIONS: The SF-guided technique is suitable for HGG surgery but not for LGG surgery. Downregulation of claudin-5 expression may contribute to the presence of yellow fluorescence in the glioma in SF-guided surgery.


Assuntos
Barreira Hematoencefálica/lesões , Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Procedimentos Neurocirúrgicos/métodos , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Claudina-5/biossíntese , Meios de Contraste , Regulação para Baixo , Feminino , Fluoresceína , Fluorescência , Glioma/diagnóstico por imagem , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Resultado do Tratamento
17.
J Med Chem ; 61(1): 265-285, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29190083

RESUMO

Herein, we report the discovery and characterization of a novel class of PAK4 inhibitors with a quinazoline scaffold. Based on the shape and chemical composition of the ATP-binding pocket of PAKs, we chose a 2,4-diaminoquinazoline series of inhibitors as a starting point. Guided by X-ray crystallography and a structure-based drug design (SBDD) approach, a series of novel 4-aminoquinazoline-2-carboxamide PAK4 inhibitors were designed and synthesized. The inhibitors' selectivity, therapeutic potency, and pharmaceutical properties were optimized. One of the best compounds, 31 (CZh226), showed remarkable PAK4 selectivity (346-fold vs PAK1) and favorable kinase selectivity profile. Moreover, this compound potently inhibited the migration and invasion of A549 tumor cells by regulating the PAK4-directed downstream signaling pathways in vitro. Taken together, these data support the further development of 31 as a lead compound for PAK4-targeted anticancer drug discovery and as a valuable research probe for the further biological investigation of group II PAKs.


Assuntos
Desenho de Fármacos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/química , Quinazolinas/farmacologia , Quinases Ativadas por p21/antagonistas & inibidores , Domínio Catalítico , Humanos , Modelos Moleculares , Inibidores de Proteínas Quinases/metabolismo , Quinazolinas/metabolismo , Relação Estrutura-Atividade , Especificidade por Substrato , Quinases Ativadas por p21/química , Quinases Ativadas por p21/metabolismo
18.
Infect Genet Evol ; 56: 111-116, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29154928

RESUMO

In this study, the thrombospondin-related adhesive protein (TRAP) gene and the heat shock protein 70 (Hsp70) gene of Babesia gibsoni isolated from the naturally infected dog in the Nanjing area were cloned and sequenced. Twenty blood samples were collected from the suspected cases of babesiosis at the animal hospital of Nanjing Agriculture University. Genomic DNA was extracted from the blood samples, and the 18S rDNAs were amplified by PCR to confirm Babesia infection. As a result, 10 cases of Babesia 18S rDNA gene amplification were positive in the 20 blood samples, confirming that the 10 cases were infected with canine Babesia. The TRAP and the Hsp70 gene fragments were amplified from all 10 positive cases. The four isolates, named NJN1, NJN2, NJN3 and NJN4, were sequenced and compared with other isolates in Asian. The similarity of TRAP and Hsp70 gene sequences among four isolates in Nanjing were above 99%. The Nanjing isolates were closely related to isolates from Taiwan and Japan. Indian isolates were different form Chinese and Japanese isolates, despite the very high similarity of the 18s rRNA genes sequence. These results suggest that the TRAP and Hsp70 genes have a reference value for the genetic diversity analysis of Babesia gibsoni.


Assuntos
Babesia/classificação , Babesia/genética , Moléculas de Adesão Celular/genética , Doenças do Cão/parasitologia , Proteínas de Choque Térmico HSP70/genética , Trombospondinas/genética , Animais , Moléculas de Adesão Celular/química , Doenças do Cão/diagnóstico , Cães , Evolução Molecular , Proteínas de Choque Térmico HSP70/química , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Avaliação de Sintomas , Trombospondinas/química
19.
Chin J Nat Med ; 15(7): 515-524, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28807225

RESUMO

Scutellariae Radix (SR), the root of Scutellaria baicalensis Georgi, is used as an antipyretic drug and has been demonstrated to have anti-inflammatory activity. SR is divided into two specifications, "Ku Qin" (KQ) and "Zi Qin" (ZQ), for use against different symptoms (upper energizer heat or lower portion of the triple energizer), according to the theory of traditional Chinese medicine (TCM). However, differences in the efficacies of these two specifications have not been determined. In the present study, we aimed to characterize the differences in the anti-inflammatory activities between KQ and ZQ and to explore how their differences are manifested in lipopolysaccharide (LPS)-induced macrophages. Our results showed that, in RAW264.7 cells (a mouse macrophage cell line derived from ascites), KQ and ZQ displayed anti-inflammatory effects by inhibiting the release of nitric oxide (NO), inducible NOS (iNOS), and nuclear factor-κB (NF-κB) in a dose-dependent manner without distinction. In NR8383 cells (a rat alveolar macrophage cell line), KQ and ZQ displayed similar effects on NO, iNOS, and NF-κB as seen in RAW264.7 cells, but KQ showed a higher inhibition rate for NO and iNOS than that shown by ZQ at the same concentration. These results indicated that there were differences in efficacy between KQ and ZQ in treating lung inflammation. Our findings provided an experimental evidence supporting the different uses of KQ and ZQ in clinic, as noted in ancient herbal records.


Assuntos
Anti-Inflamatórios/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Scutellaria baicalensis/química , Animais , Linhagem Celular , Macrófagos/imunologia , Camundongos , NF-kappa B/genética , NF-kappa B/imunologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Células RAW 264.7 , Ratos
20.
CNS Neurosci Ther ; 23(1): 57-68, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27534449

RESUMO

AIM: Infantile spasms (IS) are an age-specific epileptic syndrome with specific clinical symptom and electroencephalogram (EEG) features, lacking treatment options, and a poor prognosis. Excessive endogenous corticotropin-releasing hormone (CRH) in infant brain might result in IS. However, the data from human IS are limited. In our study, we investigated the expressions of CRH and its receptor type 1 (CRHR1) in surgical tissues from patients with IS and autopsy controls. METHODS: Specimens surgically removed from 17 patients with IS, and six autopsy controls were included in the study. Real-time PCR, Western blotting, and immunostaining were used to detect the expressions of mRNA, protein expression, and distribution. The correlation between variates was analyzed by Spearman rank correlation. RESULTS: The expressions of CRH and CRHR1 were significantly upregulated in the epileptogenic tissues of IS patients compared with the control group. CRH was distributed mainly in neurons, while CRHR1 was distributed in neurons, astrocytes, and microglia. The expression levels of CRH and CRHR1 were positively correlated with the frequency of epileptic spasms. Moreover, the expression of protein kinase C (PKC), which was an important downstream factor of CRHR1, was significantly upregulated in the epileptogenic tissues of patients with IS and was positively correlated with the CRHR1 expression levels and the frequency of epileptic spasms. CONCLUSION: These results suggest that the CRH signal transduction pathway might participate in the epileptogenesis of IS, supporting the hypothesis that CRH is related to the pathogenesis of IS.


Assuntos
Córtex Cerebral/metabolismo , Hormônio Liberador da Corticotropina/metabolismo , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Espasmos Infantis/patologia , Regulação para Cima/fisiologia , Adolescente , Adulto , Autopsia , Córtex Cerebral/patologia , Criança , Hormônio Liberador da Corticotropina/genética , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Proteínas de Neurofilamentos/metabolismo , Proteína Quinase C/metabolismo , RNA Mensageiro/metabolismo , Receptores de Hormônio Liberador da Corticotropina/genética , Transdução de Sinais/fisiologia , Espasmos Infantis/diagnóstico por imagem , Estatísticas não Paramétricas , Adulto Jovem
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