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The secure transmission of data within a network has received great attention. As the core of the security management mechanism, the key management scheme design needs further research. In view of the safety and energy consumption problems in recent papers, we propose a key management scheme based on the pairing-free identity based digital signature (PF-IBS) algorithm for heterogeneous wireless sensor networks (HWSNs). Our scheme uses the PF-IBS algorithm to complete message authentication, which is safer and more energy efficient than some recent schemes. Moreover, we use the base station (BS) as the processing center for the huge data in the network, thereby saving network energy consumption and improving the network life cycle. Finally, we indirectly prevent the attacker from capturing relay nodes that upload data between clusters in the network (some cluster head nodes cannot communicate directly). Through performance evaluation, the scheme we proposed reasonably sacrifices part of the storage space in exchange for entire network security while saving energy consumption.
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Peptic ulcer disease is a common gastrointestinal tract disorder that affects up to 20% of the population of the world. Treatment of peptic ulcer remains challenging due to the limited effectiveness and severe side effects of the currently available drugs. Hence, natural compounds, owing to their medicinal, ecological, and other safe properties, are becoming popular potential candidates in preventing and treating peptic ulcers. Flavonoids, the most abundant polyphenols in plants, exhibit gastroprotective effects against peptic ulcer both in vivo and in vitro. In this review, we summarized the anti-ulcer functions and mechanisms, and also the bioavailability, efficacy, and safety, of flavonoid monomers in the gastrointestinal tract. Flavonoids exerted cytoprotective and rehabilitative effects by not only strengthening defense factors, such as mucus and prostaglandins, but also protecting against potentially harmful factors via their antioxidative, anti-inflammatory, and antibacterial activities. Although controlled clinical studies are limited at present, flavonoids have shown a promising preventable and therapeutic potential in peptic ulcers.
Assuntos
Anti-Inflamatórios/uso terapêutico , Flavonoides/uso terapêutico , Úlcera Péptica/tratamento farmacológico , Antioxidantes/uso terapêutico , Flavonoides/efeitos adversos , HumanosRESUMO
Cinnamomum cassia Presl. (CCP) is a popular natural spice possessing various pharmacological properties. We obtained polyphenol-rich fraction (CCP-P) from CCP by bioactivity-oriented purification method and evaluated its Wnt signaling inhibition activity. Firstly, the phenolic components were identified as the main bioactive compounds with anti-colorectal cancer activity. Then, we compared the anti-colorectal cancer activity of CCP extract obtained from different solvent by cell morphology alteration and EdU assay. Ethanol extract showed higher antiproliferative activity compared to water extract on HCT116 cells, with proliferating cells reducing to 41.12 and 21.83% at 156.00 µg GAE/mL, respectively. Next, separation and enrichment of polyphenols from ethanol extract was performed on AB-8 macroporous resins under optimal conditions. Further evaluation of the CCP-P bioactivity revealed that it exerted more potent antiproliferative activity on RKO and HCT116 cells, showing higher selectivity for Wnt-dependent colorectal cancer cells (CRCs). Ten major polyphenols were identified in the CCP-P by UPLC-ESI-MS/MS. In summary, this study presents evidence that CCP-derived polyphenols are promising potential candidates as functional food ingredients against CRC.
Assuntos
Cinnamomum aromaticum , Neoplasias Colorretais , Neoplasias Colorretais/tratamento farmacológico , Humanos , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Espectrometria de Massas em TandemRESUMO
Growing concern is about the potential side effects of nanomaterials from food packaging, notably zinc oxide nanoparticles (nZnO). Previous research revealed that walnut-derived peptides could mitigate this inhibitory effect, but the mechanism involved is unclear. Here, we found that not all peptides have such an effect. Based on the growth inhibition model of Lactobacillus rhamnosus LRa05 induced by nZnO, we assessed the protective effects of various peptides. Notably, four peptides containing charged amino acids (PPKNW, WPPKN, ADIYTE, and WEREEQE) were found to effectively alleviate the growth inhibition phenomenon. We hypothesize that the peptide-nZnO interaction modifies this effect, as confirmed through infrared, Raman, and fluorescence spectroscopy. Our results highlight amide bonds, amino groups, carboxyl groups, and benzene rings as key peptide binding sites on nZnO, with static quenching primarily due to hydrogen bonds and van der Waals forces. This study elucidates peptide characteristics in nZnO interactions, facilitating a deeper exploration of food matrix-nanocomposite interactions.
Assuntos
Lacticaseibacillus rhamnosus , Nanopartículas , Óxido de Zinco , Aminoácidos , Nanopartículas/química , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Peptídeos/farmacologiaRESUMO
The interaction between zinc oxide nanoparticles (ZnO NPs) and whey protein (WP) was studied. The gastric epithelial cell line (GES-1) was used to evaluate the toxicity intensity of ZnO NPs. The interaction mechanism of ZnO NPs and WP was studied by spectroscopic techniques. The results showed that the inhibitory effect of ZnO NPs on cells activity could be reduced when added to ZnO NPs at a concentration of 50 µg/ml. The fluorescence quenching mechanism of ZnO NPs on WP is a combination of dynamic and static quenching. The interaction force between ZnO NPs and WP can be considered as H-bond and VdW force, and they have two binding sites. The interaction between WP and ZnO NPs leads to the loosening of the structural skeleton of WP and the extension of peptide chain, which exposes the tyrosine (Tyr) and tryptophan (Trp) hydrophobic groups in the hydrophobic region of protein molecules and reduces the hydrophobicity of the microenvironment. The ZnO NPs might form a complex with WP through H-bond, hydrophobic interactions, and so on, leading to peptide chain rearrangement, and finally causing changes in the secondary structure of α-helix. Practical Application This study provides a theoretical basis for future research on the interaction between food ingredients and nanomaterials, the evaluation of toxicity of nanomaterials and the application scope of nanomaterials in food field.
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Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Nanopartículas/química , Nanopartículas/toxicidade , Estrutura Secundária de Proteína , Proteínas do Soro do Leite/toxicidade , Óxido de Zinco/química , Óxido de Zinco/toxicidadeRESUMO
Hericium erinaceus, a traditional edible mushroom, is known as a medicine food homology to ameliorate gastrointestinal diseases. However, the relationship between the structural characteristics of Hericium erinaceus and its stomach-protecting activity remains unclear. Here, the structural properties of two polysaccharides from Hericium erinaceus, mycelium polysaccharide (HMP) and fruiting body polysaccharide (HFP) were investigated by spectral approaches. The results showed that the distribution of HMP was more uniform compared to HFP. Both HMP and HFP have triple helix structures, but the HMP conformation showed greater stability. Subsequently, the preventive effect of HMP and HFP on ethanol-induced gastric mucosal injury was also evaluated in rats and GES-1 cells, and it showed that both HMP and HFP had significant protective activity against gastric mucosal injury, but HMP showed better activity than HFP. These results suggested that conformational stability polysaccharide in Hericium erinaceus is more related to its gastric-protecting activity.
Assuntos
Basidiomycota , Polissacarídeos , Animais , Etanol , Mucosa Gástrica , Hericium , RatosRESUMO
Food-derived bioactive peptides, encrypted in native protein sequence, have attracted enormous research attention due to its potential in the prevention and/or treatment of a broad range of diseases. However, administration route poses a great challenge to their development and commercial applications. Patient-friendly delivery of bioactive peptides which also enhances its efficacy urgently remain to be addressed. Here we compared the effects of oral administration (PO) to intraperitoneal injection (IP) of a walnut-derived bioactive pentapeptide PW5 (Pro-Pro-Lys-Asn-Trp) in cognitive improvement capacity in APPSWE/PS1ΔE9 transgenic mice. Strikingly, we found that only PO administration of PW5 could effectively ameliorate cognitive impairments and reduce the ß-amyloid deposits in the brain compared to the IP administration. This may be attributable to alterations in the gut microbiota communities, including alterations in microbial α- and ß-diversities after PO treatment, leading to the reversal of the relative abundances of ten differential genera (e.g. Acinetobacter, Lactobacillus, Akkermansia, Allobaculum, Adlercreutzia, Coriobacteriaceae, unclassified_p_ Firmicutes, Desulfovibrionaceae, Oscillospira and Anaeroplasma) which are highly correlated with disease progression. Thus, this study has leveraged on PW5 to proof the superior efficacy of oral delivery to injection delivery in improving cognitive impairments in vivo, suggesting that oral delivery might be highly recommended as a prioritized delivery route in the development of food-derived peptides.
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Doença de Alzheimer , Disfunção Cognitiva , Juglans , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Disfunção Cognitiva/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Injeções Intraperitoneais , Juglans/metabolismo , Camundongos , Camundongos TransgênicosRESUMO
Liver injury is a significant public health issue nowadays. Shibi tea is a non-Camellia tea prepared from the dried leaves of Adinandra nitida, one of the plants with the greatest flavonoid concentration, with Camellianin A (CA) being the major flavonoid. Shibi tea is extensively used in food and medicine and has been found to provide a variety of health advantages. The benefits of Shibi tea and CA in preventing liver injury have not yet been investigated. The aim of this study was to investigate the hepatoprotective effects of extract of Shibi tea (EST) and CA in mice with carbon tetrachloride (CCl4)-induced acute liver injury. Two different concentrations of EST and CA were given to model mice by gavage for 3 days. Treatment with two concentrations of EST and CA reduced the CCl4-induced elevation of the liver index, liver histopathological injury score, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Western blotting and immunohistochemical analysis demonstrated that EST and CA regulated the oxidative stress signaling pathway protein levels of nuclear factor E2-related factor 2 (Nrf2)/heme-oxygenase-1 (HO-1), the expression of inflammatory cytokines, the phosphorylated nuclear factor-kappaB p65 (p-NF-κB)/nuclear factor-kappaB p65 (NF-κB) ratio, the phospho-p44/42 mitogen-activated protein kinase (p-MAPK), and the apoptosis-related protein levels of BCL2-associated X (Bax)/B cell leukemia/lymphoma 2 (Bcl2) in the liver. Taken together, EST and CA can protect against CCl4-induced liver injury by exerting antioxidative stress, anti-inflammation, and anti-apoptosis.
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Doença Hepática Induzida por Substâncias e Drogas , Flavonoides , Chás de Ervas , Animais , Apoptose , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Flavonoides/farmacologia , Inflamação/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de SinaisRESUMO
Gastric mucosal injury is a common gastrointestinal disorder. Hericium erinaceus polysaccharide, the major active ingredient in Hericium erinaceus, can reduce gastric mucosal damage to some extent. In this study, two different products HMP-Vc and HMP-Ce were obtained by Vitamin C and cellulase degradation of Hericium erinaceus mycelium polysaccharide (HMP). The gastroprotective activity of polysaccharides and its interaction products with food additives silica nanoparticles (nSiO2) were studied in GES-1 cells. It was found that gastroprotective activity of HMP was significantly higher than that of degradation products, and the addition of nSiO2 could enhance this activity of HMP. The greatest difference between the degradation products and HMP was the reduction of the triple helix structure, which might be the reason of the gastroprotective activity was less than that of HMP. Moreover, nSiO2 might interact with HMP through hydrogen bonding to enhance its activity.
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Resveratrol has a variety of physiological activities, but its bioavailability in the body is low. In this study, the interaction between the peptide SH, prepared from Scomberomorus niphonius, and resveratrol was judged by fluorescence spectroscopy. Then, SHa1 was obtained by the purification of SH, and its effect on the characteristics of resveratrol was studied. SHa1 interacted with resveratrol at 37 °C for 30 min to obtain the complex SHa1-R, which then showed an obviously stronger inhibition on B16 cells than resveratrol using the MTT assay after in vitro gastrointestinal digestion. The solubility and digestive stability of SHa1-R were higher than that of free resveratrol. The intestinal absorption rate of SHa1-R was also increased compared with resveratrol according to the non-inverted rat intestinal sac model. The structure of SHa1 was analyzed by UPLC, auto amino acid analysis, and UPLC-MS/MS. The molecular weight of SHa1 was mainly concentrated under 1000 Da, and it was rich in glutamic acid, aspartic acid, lysine, and leucine. Eighteen possible peptides were identified from SHa1. The results suggested that the peptide SHa-1 may help to increase the bioavailability of resveratrol by increasing the solubility, digestive stability and intestinal absorption of resveratrol, thereby promoting its inhibitory effect on B16 cells.
Assuntos
Proteínas de Peixes , Resveratrol , Animais , Linhagem Celular Tumoral , Proteínas de Peixes/química , Proteínas de Peixes/metabolismo , Proteínas de Peixes/farmacologia , Absorção Intestinal/efeitos dos fármacos , Masculino , Camundongos , Peptídeos/química , Peptídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Resveratrol/química , Resveratrol/metabolismo , Resveratrol/farmacocinética , Solubilidade , Espectrometria de FluorescênciaRESUMO
The impairment of cognitive function was considered as a major clinic feature in Alzheimer's disease (AD) patients. Thus, a number of researches related to AD were focused on the changes in brain. However, as a neurodegenerative disorder with systemic inflammation, the periphery organs may also play a key role in AD pathology. Here, we pose the hypothesis that histopathology and inflammatory response of periphery organs may alter with aging in APP/PS1 mouse model. Therefore, we performed immunohistochemical staining technology to double label Aß plaques and microglia cells in brain. The H&E staining was performed in periphery tissues and the mRNA expression of inflammatory factors IL-6, IL-10 and TNF-α were also determined. Next, the index of oxidative stress was measured. Consequently, the level of inflammatory factors was significantly increased in 24 months APP/PS1 mice. Furthermore, the enzyme activity of SOD, CAT and GSH were significantly decreased in colon and other organs. Our results demonstrated the increased inflammation response and declined antioxidative capacity of periphery organs in aged APP/PS1 mice, which suggesting that a more comprehensive perspective to study AD were necessary.
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Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Idoso , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Precursor de Proteína beta-Amiloide/genética , Animais , Modelos Animais de Doenças , Humanos , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Presenilina-1/genéticaRESUMO
The mitochondrial theory of aging postulates that accumulation of mtDNA mutations and mitochondrial dysfunction are responsible for producing aging phenotypes. To more comprehensively explore the complex relationship between aging and mitochondria dysfunction, we have developed a mouse model with Slc25a46 knockout, a nuclear gene described as encoding mitochondrial carriers, by CRISPR/Cas9 gene editing to mimic some typical aging phenotypes in human. Slc25a46-/- mice present segmental premature aging phenotypes characterized by shortened life span of no more than 2 months, obviously defective motor ability, gastrocnemius muscle atrophy, and imbalance of redox level in brain and liver. The underlying mechanism for multiple organ disorder may attribute to mitochondrial dysfunction, which is mainly manifested in the damaged mitochondrial structure (eg, vacuolar structure, irregular swelling, and disorganized cristae) and an age-associated decrease in respiratory chain enzyme (mainly complex I and IV) activity. In summary, our study suggests that the Slc25a46-/- mouse is a valid animal model for segmental aging-related pathologies studies based on mitochondrial theory, generating a new platform to both understand mechanisms between aging and mitochondria dysfunction as well as to design mitochondria-based therapeutic strategies to improve mitochondrial quality, and thereby the overall healthspan.
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Envelhecimento/patologia , Envelhecimento/fisiologia , Doenças Mitocondriais/etiologia , Proteínas Mitocondriais/fisiologia , Transtornos Motores/etiologia , Estresse Oxidativo/fisiologia , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Knockout , OxirreduçãoRESUMO
In this study a complex of naringenin with hydroxypropyl-beta-cyclodextrin (HP-beta-CD) was prepared to improve the hydrophilicity of naringenin. The physicochemical properties of the complex were analyzed by ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), X-ray diffractometry (XRD), differential scanning calorimetry (DSC). The result showed that naringenin had been molecularly dispersed in the HP-beta-CD matrix, not forming a new compound and HPLC analysis showed that the solubility of naringenin in water was enhanced from 4.38 microg/mL to 1,272.31 microg/mL.
Assuntos
Flavanonas/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Varredura Diferencial de Calorimetria , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Difração de Raios XRESUMO
CONTEXT: Adinandra nitida Merr. ex. H.L. Li (Theaceae) is an indigenous plant in south China. Its leaves have been reported to have many curative effects such as reducing blood pressure, as well as antibacterial, antioxidant, and analgesic properties, which could be used in foods and medicines. OBJECTIVE: The antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of the main flavonoids and ethanol extract (EE) of A. nitida leaves were investigated for the first time. MATERIALS AND METHODS: The main flavonoids of A. nitida leaves (camellianin A, camellianin B) were prepared and their contents in EE were determined by HPLC. The antioxidant activities of the samples were measured by DPPH radical scavenging assay and Rancimat test. The ACE inhibitory activities of the samples were carried out by using an assay kit with hippuryl-glycyl-glycine as substrate. RESULTS: The contents of camellianin A, camellianin B and apigenin in EE were determined as 41.98, 2.67, and 1.73%, respectively. The antioxidant activities of the flavonoids were far lower than that of EE in DPPH radical scavenging and Rancimat assays. However, the ACE-inhibitory activities of camellianin A, camellianin B and apigenin were higher than that of EE. DISCUSSION AND CONCLUSION: The flavonoid content of EE was more than 45%. The high activities of EE in DPPH scavenging and Rancimat assay could be mainly attributed to compounds other than flavonoids. However, the ACE-inhibitory activity of EE could be mainly attributed to the presence of the flavonoids.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Theaceae/química , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Etanol/química , Flavonoides/isolamento & purificação , Humanos , Extratos Vegetais/farmacologia , Folhas de Planta , Solventes/químicaRESUMO
The polyphenols (PF) from Platycladus Orientalis (L.) Franco leaves were purified by using 10 different macroporous adsorption resins. HPD-722 resin showed the best adsorption and desorption capacities. The static and dynamic adsorption and desorption of PF on HPD-722 resin were studied and the total polyphenols were separated into two fractions, PF-A and PF-B. PF-A and PF-B demonstrated similar scavenging activity of free radical (DPPH, ABTS, hydroxyl radical, superoxide anion). The scavenging activity of PF-A and PF-B on hydroxyl radical and superoxide anion radical reached the equal levels of vitamin C and gallic acid. The IC50 value of PF-A for hydroxyl radical scavenging activity and superoxide anion radical scavenging activity were 0.50 and 0.56 mg/mL, while those of PF-B were 0.61 and 0.64 mg/mL. PF-A and PF-B could reduce the overproduction of inflammatory cytokines (TNF-α, Pro-IL-1ß, and IL-6) induced by lipopolysaccharide and their protein expression in THP-1 cells. PF-B exhibited better anti-inflammatory effect than PF-A in the dosage range of 1.0-4.0 µg/mL. Structural identification of PF-A and PF-B were conducted by HPLC-MS/MS. Ten polyphenol compounds were identified in PF-A and PF-B, respectively, by HPLC-MS/MS, including quercetin, apigenin, myricetin, and so on. Molecular docking studies indicated that apigenin, myricetin, luteolin, kaempferol, and quercetin effectively inhibit xanthine oxidase by forming hydrogen bonds with the amino acid residues and binding to the active site of the enzyme. The results might supply useful information for better understanding the chemical structure, antioxidant, and anti-inflammatory activities of Platycladuso (L.) Franco leaves polyphenols. PRACTICAL APPLICATION: This study demonstrated that polyphenols from P. orientalis (L.) Franco leaves have the potential applications as functional food ingredient for the prevention and treatment of gout and inflammation, hyperuricemia and gout.
Assuntos
Cupressaceae/química , Polifenóis/química , Antioxidantes , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Citocinas/genética , Citocinas/metabolismo , Sequestradores de Radicais Livres , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Extratos Vegetais , Folhas de Planta/química , Superóxidos , Espectrometria de Massas em TandemRESUMO
The structure and bioactivity of a novel polysaccharide from Platycladus orientalis (L.) Franco leaves (POP2) were investigated in the present study. Structure characterization demonstrated that the average molecular weight of POP2 was 9.69 kDa and consisted of arabinose (14.39%), mannose (10.24%), glucose (63.95%) and galactose (11.42%). The main linkage types of POP2 consisted of (1â4)-linked α-d-Glc and (1â6)-linked α-d-Glc based on methylation and NMR analysis. Bioactivity evaluation showed that POP2 could effectively promote the secretion of inflammatory cytokines (IL-6 and TNF-α), as well as the anti-inflammatory cytokines (IL-10) in LPS-induced cells. Besides, the secretion of NO was significantly inhibited by POP2 in M1 model. POP2 could enhance the level of inflammatory cytokines (NO, IL-6 and TNF-α), while the secretion of the anti-inflammatory cytokine TGF-ß was markedly suppressed in IL-4 induced cells. Our work attempted to elucidate the regulation of macrophage polarization and support the potential application of POP2 as bioactive ingredient for functional foods.
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Cupressaceae/química , Macrófagos/efeitos dos fármacos , Polissacarídeos/farmacologia , Animais , Polaridade Celular/efeitos dos fármacos , Células Cultivadas , Macrófagos/metabolismo , Camundongos , Folhas de Planta/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Células RAW 264.7RESUMO
Two novel peptides WW4 and WW7 were evaluated for their antioxidant activity, membrane penetrance and inhibiting activity of amyloid-ß protein (Aß) aggregation. The results showed that both WW7 (10.38 ± 0.22 µmol TE per µmol) and WW4 (6.32 ± 0.77 µmol TE per µmol) possessed a significant oxygen radical absorption capacity (ORAC) and strong 1,1-diphenyl-2-picrylhydrazyl (DPPHË) scavenging capacity (WW7, IC50 0.05 ± 0.002; WW4, 1.06 ± 0.07). Interestingly, WW7 exhibited relatively higher antioxidant activity than WW4. In addition, both WW4 and WW7 showed high cell membrane penetrance characteristics in HEK293 cells. To measure the metabolic stability of WW4 and WW7 in cells, we labelled the peptides with FITC and then analyze the co-localization with lysosomes by imaging Flow-cytometry. We found that WW7 had a lower co-localization rate (1.39%) than WW4 (8.44%), indicating that WW7 was more stable than WW4. In vivo imaging assay demonstrated that WW7 presented higher metabolic stability with a much longer stability time (2687.33 ± 54.01 min) in BALB-c nude mice than WW4 (148 ± 26.85 min), which was consistent with the in vitro result. To illustrate the potential function of antioxidant capacity, an Aß aggregation cell model was applied to examine anti-Aß aggregation ability of WW4 and WW7. Surprisingly, WW7 (23.04 ± 13.64%) had stronger anti-Aß aggregation ability but WW4 did not show obvious potential, which was due to their structure difference. The present work would offer novel insight into the activity of antioxidants and anti-Aß aggregation, and uncover the under-appreciated function of peptides in effective application in AD therapy.
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Peptídeos beta-Amiloides/química , Antioxidantes/farmacologia , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Antioxidantes/química , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Nus , Peptídeos/químicaRESUMO
Hyperuricemia is a metabolic disease caused by disorders of purine metabolism, the prevalence of which has increased worldwide. Here, a cell model for high uric acid production was established in vitro employing cultured human kidney cells (HK-2â¯cells), and its molecular basis was analyzed using gene expression profile. High performance liquid chromatography (HPLC) was used to monitor the content of metabolites in cell culture media. Adenosine addition was found to induce HK-2â¯cells to produce uric acid precursors (inosine and hypoxanthine). Furthermore, the cell model was verified by confirming the antihyperuricemic effect of the widely used antihyperuricemic drugs allopurinol, probenecid, and febuxostat, as well as reported bioactive peptides and amino acids, encompassing glutathione, tryptophan and carnosine, which significantly reduced uric acid production in the HK-2â¯cells (pâ¯<â¯0.05). RNA-Seq technology was used to perform a wide transcriptome analysis of the hyperuricemic cell model, and the results demonstrated that it has the potential to be used as a rapid and valid in vitro model to screen antihyperuricemic compounds that mimics in vivo cell growth patterns.
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Técnicas de Cultura de Células/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Túbulos Renais/efeitos dos fármacos , Ácido Úrico/análise , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Humanos , Hiperuricemia , Túbulos Renais/metabolismo , Xantina Oxidase/antagonistas & inibidoresRESUMO
OBJECTIVE: To isolate and identify the new Bdellovibrio strains from the sea mud of Shenzhen bay and to preliminarily study their biological characteristics. METHODS: We isolated Bdellovibrio strains by DNB(dilute nutrient broth) double-layer plate method. Their 16S rDNAs were sequenced and their morphologies were examined under electron microscope. We identified these strains according to the ninth edition of Bergey's manual of determinative bacteriology. We also studied their biological characteristics through physiological tests. RESULTS: We isolated 2 strains of Bdellovibrio sp. (5#-12 and 5#-sh06) from sea mud of Shenzhen bay. Both strains grew between 209C and 35 degrees C, with 259C and 309C as optimal temperature for 5#-12 and 5#-sh06, respectively. They grew between pH 6.1 and 8.6, and the opticCmal pH for both was 7.2. Lysis experiments on 58 strains of pathogens were conducted and the results showed that 5#-12 and 5#-sh06 lysed 46 and 48 strains, corresponding to 79.3% and 82.8% of lysis abilities. Taken both two Bdellovibrio strains together, they lysed 96.6% (56 strains) of tested pathogens and 100% of tested vibrios (39 strains). CONCLUSION: The results demonstrated that Bdellovibrio have potential and significant application prospect for elimination of pathogens.
Assuntos
Bdellovibrio/isolamento & purificação , DNA Ribossômico/análise , RNA Ribossômico 16S/análise , Sequência de Bases , Bdellovibrio/classificação , Bdellovibrio/genética , DNA Bacteriano/análise , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , TemperaturaRESUMO
Traditional drugs used to treat hyperuricemia have adverse effects. In this study, to identify safer anti-hyperuricemic bioactive peptides isolated from food-derived protein hydrolysates, a hyperuricemia rat model induced by potassium oxonate (PO) was used to evaluate the activity of bonito hydrolysates (BH), dephenolised walnut hydrolysates (DWH), and soybean hydrolysates (SH). The serum uric acid level of rats in the BH group (95.4 ± 27.4 µM, p < 0.01) was significantly reduced compared to that in the model group (212.00 ± 30.00 µM) to a level even lower than that in allopurinol group (114.3 ± 53.0 µM). Furthermore, BH alleviated renal impairment caused by PO in vivo and exhibited the greatest xanthine oxidase (XOD) inhibitory activity (65.5 ± 8.0%) in vitro compared to the other hydrolysates. Two peptides identified from BH bound the catalytic site of XOD, among which the hydrophobic peptide WML entered the active site of XOD more easily compared to the hydrophilic peptide PGACSN, possibly because of hydrophobic interactions. The chemically synthesized WML demonstrated high XOD inhibitory effect compared to PGACSN and a significant change in the secondary structure of XOD. Therefore, hexapeptide PGACSN and tripeptide WML are partially responsible for the anti-hyperuricemic activity of BH, and hydrophobic amino acids play important roles in the XOD inhibitory activity of peptides.