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1.
Discov Oncol ; 15(1): 122, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625419

RESUMO

PURPOSE: The Gleason score (GS) and positive needles are crucial aggressive indicators of prostate cancer (PCa). This study aimed to investigate the usefulness of magnetic resonance imaging (MRI) radiomics models in predicting GS and positive needles of systematic biopsy in PCa. MATERIAL AND METHODS: A total of 218 patients with pathologically proven PCa were retrospectively recruited from 2 centers. Small-field-of-view high-resolution T2-weighted imaging and post-contrast delayed sequences were selected to extract radiomics features. Then, analysis of variance and recursive feature elimination were applied to remove redundant features. Radiomics models for predicting GS and positive needles were constructed based on MRI and various classifiers, including support vector machine, linear discriminant analysis, logistic regression (LR), and LR using the least absolute shrinkage and selection operator. The models were evaluated with the area under the curve (AUC) of the receiver-operating characteristic. RESULTS: The 11 features were chosen as the primary feature subset for the GS prediction, whereas the 5 features were chosen for positive needle prediction. LR was chosen as classifier to construct the radiomics models. For GS prediction, the AUC of the radiomics models was 0.811, 0.814, and 0.717 in the training, internal validation, and external validation sets, respectively. For positive needle prediction, the AUC was 0.806, 0.811, and 0.791 in the training, internal validation, and external validation sets, respectively. CONCLUSIONS: MRI radiomics models are suitable for predicting GS and positive needles of systematic biopsy in PCa. The models can be used to identify aggressive PCa using a noninvasive, repeatable, and accurate diagnostic method.

2.
Food Chem ; 450: 139309, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38631200

RESUMO

Flammulina velutipes, a widely cultivated species of edible fungus, exhibits diverse functional activities attributed to its polysaccharides. In this study, we employed an in vitro model to investigate the impact of F. velutipes polysaccharides (FVP) fermentation on gut microbiota, with a particular focus on Bacteroides. FVP fermentation resulted in the proliferation of microbiota associated with short-chain fatty acid (SCFA) metabolism and suppression of Escherichia-Shigella. Bacteroides emerged as potential primary degraders of FVP, with species-level analysis identifying the preference of B. thetaiotaomicron and B. intestinalis in FVP degradation. Metabolomics analysis revealed significant increases in hypoxanthine and 7-methyladenine contents, with histidine metabolism emerging as the most enriched pathway. B. nordii and B. xylanisolvens exhibited the most influence on amino acid and SCFA metabolism. Understanding the mechanisms by which gut microbiota metabolize FVP can provide valuable insights into the potential of FVP to promote intestinal health and disease prevention.

3.
Oncogene ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632437

RESUMO

Pyruvate kinase M2 (PKM2) is a central metabolic enzyme driving the Warburg effect in tumor growth. Previous investigations have demonstrated that PKM2 is subject to O-linked ß-N-acetylglucosamine (O-GlcNAc) modification, which is a nutrient-sensitive post-translational modification. Here we found that unc-51 like autophagy activating kinase 1 (ULK1), a glucose-sensitive kinase, interacts with PKM2 and phosphorylates PKM2 at Ser333. Ser333 phosphorylation antagonizes PKM2 O-GlcNAcylation, promotes its tetramer formation and enzymatic activity, and decreases its nuclear localization. As PKM2 is known to have a nuclear role in regulating c-Myc, we also show that PKM2-S333 phosphorylation inhibits c-Myc expression. By downregulating glucose consumption and lactate production, PKM2 pS333 attenuates the Warburg effect. Through mouse xenograft assays, we demonstrate that the phospho-deficient PKM2-S333A mutant promotes tumor growth in vivo. In conclusion, we identified a ULK1-PKM2-c-Myc axis in inhibiting breast cancer, and a glucose-sensitive phosphorylation of PKM2 in modulating the Warburg effect.

4.
Food Res Int ; 184: 114258, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609236

RESUMO

The study aimed to determine the chemical structures of octadecatrienoic acid isomers produced by probiotics through the bioconversion of α-linolenic acid and to assess their antioxidant capacities. The chemical structures were identified using nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS), while the antioxidant capacities were evaluated in vitro and in cellular. The NMR signals obtained allowed for definitive characterization, with the main ion fragments detected being m/z 58.0062, 59.0140, 71.0141, 113.0616, 127.0777, and 181.5833. Compounds at concentrations below 40 µM maintained the antioxidant capacity of HepG2 cells by protecting endogenous antioxidative enzymes and mitochondrial membrane potential. However, doses higher than 40 µM increase oxidative damage and mitochondrial dysfunction. These results confirmed the structure of the probiotic-derived compound as trans9, trans11, cis15-conjugated linolenic acid. Additionally, appropriate doses of CLNA can alleviate oxidative stress induced by AAPH, while high doses aggravate cellular damage. These findings provide foundational information for the further exploration of probiotic-derived edible lipids.


Assuntos
Antioxidantes , Lomustina/análogos & derivados , Probióticos , Antioxidantes/farmacologia , Ácido alfa-Linolênico , Estresse Oxidativo
5.
Food Funct ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38590256

RESUMO

Inulins, galacto-oligosaccharides (GOS) and polyphenols are considered to stimulate the growth of Akkermansia muciniphila (A. muciniphila) in the gut. We performed a meta-analysis of six microbiome studies (821 stool samples from 451 participants) to assess the effects of inulin, GOS, and polyphenols on the abundance of A. muciniphila in the gut. The intervention of GOS increased the relative abundance of A. muciniphila in healthy participants. Additionally, metabolic pathways associated with carbohydrate metabolism and short-chain fatty acid release were enriched following the GOS intervention. Furthermore, after the GOS intervention, the coexisting microbial communities of A. muciniphila, such as Eubacterium hallii and Bacteroides, exhibited an enhanced correlation with A. muciniphila. In conclusion, our findings suggest that GOS may promote the growth of A. muciniphila in the gut by modulating the gut microbiota composition.

7.
Elife ; 122024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457350

RESUMO

Studies of climate variation commonly rely on chemical and isotopic changes recorded in sequentially produced growth layers, such as in corals, shells, and tree rings, as well as in accretionary deposits-ice and sediment cores, and speleothems. Oxygen isotopic compositions (δ18O) of tooth enamel are a direct method of reconstructing environmental variation experienced by an individual animal. Here, we utilize long-forming orangutan dentitions (Pongo spp.) to probe recent and ancient rainfall trends on a weekly basis over ~3-11 years per individual. We first demonstrate the lack of any consistent isotopic enrichment effect during exclusive nursing, supporting the use of primate first molar teeth as environmental proxies. Comparisons of δ18O values (n=2016) in twelve molars from six modern Bornean and Sumatran orangutans reveal a high degree of overlap, with more consistent annual and bimodal rainfall patterns in the Sumatran individuals. Comparisons with fossil orangutan δ18O values (n=955 measurements from six molars) reveal similarities between modern and late Pleistocene fossil Sumatran individuals, but differences between modern and late Pleistocene/early Holocene Bornean orangutans. These suggest drier and more open environments with reduced monsoon intensity during this earlier period in northern Borneo, consistent with other Niah Caves studies and long-term speleothem δ18O records in the broader region. This approach can be extended to test hypotheses about the paleoenvironments that early humans encountered in southeast Asia.


When an animal drinks water, two naturally occurring variants of oxygen ­ known as oxygen-18 and oxygen-16 ­ are incorporated into its growing teeth. The ratio of these variants in water changes with temperature, rainfall and other environmental conditions and therefore can provide a record of the climate during an animal's life. Teeth tend to be well preserved as fossils, which makes it possible to gain insights into this climate record even millions of years after an animal's death. Orangutans are highly endangered great apes that today live in rainforests on the islands of Borneo and Sumatra. During a period of time known as the Pleistocene (around 2.6 million years to 12,000 years ago), these apes were more widely spread across Southeast Asia. Climate records from this area in the time before human-induced climate change are somewhat limited. Therefore, fossilized orangutan teeth offer a possible way to investigate past seasonal rainfall patterns and gain insight into the kind of environments early humans would have encountered. To address this question, Smith et al. measured oxygen-18 and oxygen-16 variants in thin slices of modern-day orangutan teeth using a specialized analytical system. This established that the teeth showed seasonal patterns consistent with recent rainfall trends, and that the ratio of these oxygen variants did not appear to be impacted by milk intake in young orangutans. These findings indicated that the oxygen variants could be a useful proxy for predicting prehistoric weather patterns from orangutan teeth. Further measurements of teeth from fossilized Sumatran orangutans showed broadly similar rainfall patterns to those of teeth from modern-day orangutans. On the other hand, fossilized teeth from Borneo suggested that the environment used to be drier, with less intense wet seasons. The approach developed by Smith et al. provides an opportunity for scientists to leverage new fossil discoveries as well as existing collections to investigate past environments. This could allow future research into how climate variation may have influenced the spread of early humans through the region, as well as the evolution of orangutans and other endangered animals.


Assuntos
Hominidae , Pongo abelii , Dente , Animais , Humanos , Pongo pygmaeus , Sudeste Asiático
8.
Food Funct ; 15(7): 3810-3823, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38511344

RESUMO

Antibiotic treatment often causes collateral damage to the gut microbiota, including changes in its diversity and composition. Dietary fiber helps maintain intestinal health, regulate short-chain fatty acids, and promote the recovery of the intestinal microbiome. However, it is currently unknown which specific plant-based dietary fiber is optimal as a dietary supplement for restoring the intestinal microbiota after antibiotic disturbance. Previously, we proposed predictive recovery-associated bacterial species (p-RABs) and identified the most important interventions. This study aimed to identify an optimal form of dietary fiber to recover the gut microbiome after antibiotic treatment. Therefore, we examined the types of dietary fibers associated with p-RABs through a p-RAB-metabolite bilayer network constructed from prior knowledge; we searched for dietary fiber that could provide nutritional support for Akkermansia muciniphila and Bacteroides uniformis. C57BL/6J mice were fed with 500 mg kg-1 of different types of dietary fibers daily for one week after being treated with ampicillin. The results showed that mannan-oligosaccharides could better promote the diversity of intestinal microbial growth, enhance the recovery of most genera, including Akkermansia and Bacteroides, and inhibit certain pathogenic bacteria, such as Proteus, compared to the other fiber types. Furthermore, mannan-oligosaccharides could regulate the levels of short-chain fatty acids, especially butyric acid. Functional predictions showed that starch metabolism, galactose metabolism, and the metabolism of other carbohydrates played key roles in the early recovery process. In conclusion, mannan-oligosaccharides could enhance the recovery of the intestinal microbiome after antibiotic treatment, offering valuable insights for targeted dietary strategies.


Assuntos
Antibacterianos , Mananas , Animais , Camundongos , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Mananas/metabolismo , Camundongos Endogâmicos C57BL , Oligossacarídeos/farmacologia , Fibras na Dieta/metabolismo , Bactérias , Ácidos Graxos Voláteis/metabolismo
9.
J Agric Food Chem ; 72(13): 7055-7073, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38520351

RESUMO

Ulcerative colitis (UC) is a major disease that has endangered human health. Our previous study demonstrated that Bifidobacterium longum subsp. longum YS108R, a ropy exopolysaccharide (EPS)-producing bacterium, could alleviate UC in mice, but it is unclear whether EPS is the key substance responsible for its action. In this study, we proposed to investigate the remitting effect of EPS from B. longum subsp. longum YS108R on UC in a DSS-induced UC mouse model. Water extraction and alcohol precipitation were applied to extract EPS from the supernatant of B. longum subsp. longum YS108R culture. Then the animal trial was performed, and the results indicated that YS108R EPS ameliorated colonic pathological damage and the intestinal barrier. YS108R EPS suppressed inflammation via NF-κB signaling pathway inhibition and attenuated oxidative stress via the Nrf2 signaling pathway activation. Remarkably, YS108R EPS regulated gut microbiota, as evidenced by an increase in short-chain fatty acid (SCFA)-producing bacteria and a decline in Gram-negative bacteria, resulting in an increase of propionate and butyrate and a reduction of lipopolysaccharide (LPS). Collectively, YS108R EPS manipulated the intestinal microbiota and its metabolites, which further improved the intestinal barrier and inhibited inflammation and oxidative stress, thereby alleviating UC.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Camundongos , Humanos , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Bifidobacterium/metabolismo , Colo , Modelos Animais de Doenças , Bactérias , Inflamação , Sulfato de Dextrana/metabolismo , Camundongos Endogâmicos C57BL
10.
J Adv Res ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38462039

RESUMO

BACKGROUND: Population aging has become a primary global public health issue, and the prevention of age-associated diseases and prolonging healthy life expectancies are of particular importance. Gut microbiota has emerged as a novel target in various host physiological disorders including aging. Comprehensive understanding on changes of gut microbiota during aging, in particular gut microbiota characteristics of centenarians, can provide us possibility to achieving healthy aging or intervene pathological aging through gut microbiota-directed strategies. AIM OF REVIEW: This review aims to summarize the characteristics of the gut microbiota associated with aging, explore potential biomarkers of aging and address microbiota-associated mechanisms of host aging focusing on intestinal barrier and immune status. By summarizing the existing effective dietary strategies in aging interventions, the probability of developing a diet targeting the gut microbiota in future is provided. KEY SCIENTIFIC CONCEPTS OF REVIEW: This review is focused on three key notions: Firstly, gut microbiota has become a new target for regulating health status and lifespan, and its changes are closely related to age. Thus, we summarized aging-associated gut microbiota features at the levels of key genus/species and important metabolites through comparing the microbiota differences among centenarians, elderly people and younger people. Secondly, exploring microbiota biomarkers related to aging and discussing future possibility using dietary regime/components targeted to aging-related microbiota biomarkers promote human healthy lifespan. Thirdly, dietary intervention can effectively improve the imbalance of gut microbiota related to aging, such as probiotics, prebiotics, and postbiotics, but their effects vary among.

11.
PLoS One ; 19(3): e0300677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38502660

RESUMO

This study aims to integrate research in the field of aerobics and mental health through the visualization analysis method of the CiteSpace map, to clarify the impact of aerobics on mental health and stress levels. Firstly, based on the literature method, pieces of literature related to aerobics and mental health are searched and collected. Secondly, the visualization analysis method of the CiteSpace map is employed to summarize and analyze the contents of the literature, involving statistical analysis of the annual number of publications, analysis of author characteristics, and analysis of publishing institution characteristics. In addition, keyword co-occurrence analysis and keyword cluster analysis are also conducted in related research fields. Among them, the Log-Likelihood Ratio is used in keyword cluster analysis. Finally, the results are analyzed using the visualization analysis method of the CiteSpace map and the statistics-based comprehensive results. The results demonstrate that in the recent 20 years, the average annual number of articles in related fields exceeds 190. The high-yield authors are distributed in economically developed areas, and the cooperation among authors is scattered. In the keyword clustering results, a total of 77 cluster labels are obtained. The Q value of the clustering module is 0.89, and the average clustering profile silhouette (S) value is 0.92, indicating that the clustering structure is significant and the results are reasonable. The aerobics cluster contains the most closely related keywords, covering mental health and stress levels. Data analysis based on existing studies reveals that aerobics has a significant impact on mental health and stress levels. Individuals participating in aerobics show obvious improvement in mental health inventory (MHI) scores (t(100) = 4.32, p<0.05). Individuals participating in aerobics present a remarkable reduction in the questionnaire evaluation of stress levels (t(100) = -3.91, p<0.05). This study's results support aerobics' positive effects on mental health and stress levels.


Assuntos
Análise de Dados , Saúde Mental , Humanos , Análise por Conglomerados , Instalações de Saúde , Editoração
12.
World J Microbiol Biotechnol ; 40(4): 117, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38429597

RESUMO

Biofilm, a microbial community formed by especially pathogenic and spoilage bacterial species, is a critical problem in the food industries. It is an important cause of continued contamination by foodborne pathogenic bacteria. Therefore, removing biofilm is the key to solving the high pollution caused by foodborne pathogenic bacteria in the food industry. Lactobacillus, a commonly recognized probiotic that is healthy for consumer, have been proven useful for isolating the potential biofilm inhibitors. However, the addition of surface components and metabolites of Lactobacillus is not a current widely adopted biofilm control strategy at present. This review focuses on the effects and preliminary mechanism of action on biofilm inhibition of Lactobacillus-derived components including lipoteichoic acid, exopolysaccharides, bacteriocins, secreted protein, organic acids and some new identified molecules. Further, the review discusses several modern biofilm identification techniques and particularly interesting new technology of biofilm inhibition molecules. These molecules exhibit stronger inhibition of biofilm formation, playing a pivotal role in food preservation and storage. Overall, this review article discusses the application of biofilm inhibitors produced by Lactobacillus, which would greatly aid efforts to eradicate undesirable bacteria from environment in the food industries.


Assuntos
Bacteriocinas , Lactobacillus , Lactobacillus/metabolismo , Indústria Alimentícia , Indústria de Processamento de Alimentos , Bacteriocinas/farmacologia , Bacteriocinas/metabolismo , Biofilmes
13.
Food Funct ; 15(7): 3327-3339, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38465411

RESUMO

Bacteroides is a common intestinal bacterium closely associated with host colitis. However, relevant studies have been focused on the genus level, which could not identify the major Bacteroides species associated with intestinal disease. Thus, we have evaluated the Bacteroides species structure in healthy people and mouse intestinal tracts and explored the change in major Bacteroides species during colitis development. The results demonstrated that B. uniformis with a high abundance in the intestinal tract of healthy people and mice may be a core species that contributes to colitis remission. The results of animal experiments reported that B. uniformis FNMHLBE1K1 (1K1) could alleviate the severity of colitis and enhance the expression of the tight junction protein occludin by regulating gut microbiota. Notably, the protective roles of 1K1 may be attributed to some specific genes. This study revealed that B. uniformis is a key microbe influencing the occurrence and development of colitis and it provides a scientific basis for screening the next generation of probiotics.


Assuntos
Colite Ulcerativa , Colite , Humanos , Camundongos , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/genética , Colite Ulcerativa/microbiologia , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/genética , Bacteroides/genética , Intestinos , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Colo
14.
J Biol Chem ; 300(4): 107150, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38462164

RESUMO

Histone 2A monoubiquitination (uH2A) underscores a key epigenetic regulation of gene expression. In this report, we show that the deubiquitinase for uH2A, ubiquitin-specific peptidase 16 (USP16), is modified by O-linked N-acetylglucosamine (O-GlcNAc). O-GlcNAcylation involves the installation of the O-GlcNAc moiety to Ser/Thr residues. It crosstalks with Ser/Thr phosphorylation, affects protein-protein interaction, alters enzyme activity or protein folding, and changes protein subcellular localization. In our study, we first confirmed that USP16 is glycosylated on Thr203 and Ser214, as reported in a previous chemoenzymatic screen. We then discovered that mutation of the O-GlcNAcylation site Thr203, which is adjacent to deubiquitination-required Cys204, reduces the deubiquitination activity toward H2AK119ub in vitro and in cells, while mutation on Ser214 had the opposite effects. Using USP16 Ser552 phosphorylation-specific antibodies, we demonstrated that O-GlcNAcylation antagonizes cyclin-dependent kinase 1-mediated phosphorylation and promotes USP16 nuclear export. O-GlcNAcylation of USP16 is also required for deubiquitination of Polo-like kinase 1, a mitotic master kinase, and the subsequent chromosome segregation and cytokinesis. In summary, our study revealed that O-GlcNAcylation of USP16 at Thr203 and Ser214 coordinates deubiquitination of uH2A and Polo-like kinase 1, thus ensuring proper cell cycle progression.

15.
Appl Environ Microbiol ; 90(3): e0009224, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38415584

RESUMO

The gut microecological network is a complex microbial community within the human body that plays a key role in linking dietary nutrition and host physiology. To understand the complex relationships among microbes and their functions within this community, network analysis has emerged as a powerful tool. By representing the interactions between microbes and their associated omics data as a network, we can gain a comprehensive understanding of the ecological mechanisms that drive the human gut microbiota. In addition, the network-based approach provides a more intuitive analysis of the gut microbiota, simplifying the study of its complex dynamics and interdependencies. This review provides a comprehensive overview of the methods used to construct and analyze networks in the context of gut microecological background. We discuss various types of network modeling approaches, including co-occurrence networks, causal networks, dynamic networks, and multi-omics networks, and describe the analytical techniques used to identify important network properties. We also highlight the challenges and limitations of network modeling in this area, such as data scarcity and heterogeneity, and provide future research directions to overcome these limitations. By exploring these network-based methods, researchers can gain valuable insights into the intricate relationships and functional roles of microbial communities within the gut, ultimately advancing our understanding of the gut microbiota's impact on human health.


Assuntos
Microbioma Gastrointestinal , Microbiota , Humanos , Microbioma Gastrointestinal/fisiologia , Dieta , Estado Nutricional
16.
Artigo em Inglês | MEDLINE | ID: mdl-38376820

RESUMO

Lacticaseibacillus paracasei has been regarded as a probiotic bacterium because of its role in anti-inflammatory properties and maintenance of intestinal barrier permeability. Here, we explored the anticolitic effects and mechanism of L. paracasei CCFM1222. The results showed that L. paracasei CCFM1222 supplementation could suppress the disease activity index (DAI) and colon length shortening in colitis mice, accompanied by a moderate increase in colonic tight junction proteins (ZO-1, occludin and claudin-1). L. paracasei CCFM1222 intervention significantly suppressed the levels of inflammatory cytokines (TNF-α, IL-1ß, and IL-6) and significantly elevated the activities of antioxidant enzymes (including SOD, GSH-Px, and CAT) in the colon by regulating the TLR4/MyD88/NF-κB and Nrf2 signaling pathways in colitis mice. In addition, L. paracasei CCFM1222 significantly shifted the gut microbiota, including elevating the abundance of Catabacter, Ruminiclostridium 9, Alistipes, and Faecalibaculum, as well as reducing the abundance of Mucispirillum, Escherichia-Shigella, and Salmonella, which was associated with the improvement of colonic barrier damage. Overall, these results suggest that L. paracasei CCFM1222 is a good candidate for probiotic of improving colonic barrier damage and associated diseases.

17.
Microorganisms ; 12(2)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38399785

RESUMO

The development of antibiotics was a turning point in the history of medicine; however, their misuse and overuse have contributed to the current global epidemic of antibiotic resistance. According to epidemiological studies, early antibiotic exposure increases the risk of immunological and metabolic disorders. This study investigated the effects of exposure to different doses of sulfamethazine (SMZ) on offspring mice and compared the effects of exposure to SMZ on offspring mice in prenatal and early postnatal periods and continuous periods. Furthermore, the effects of SMZ exposure on the gut microbiota of offspring mice were analyzed using metagenome. According to the results, continuous exposure to high-dose SMZ caused weight gain in mice. IL-6, IL-17A, and IL-10 levels in the female offspring significantly increased after high-dose SMZ exposure. In addition, there was a significant gender difference in the impact of SMZ exposure on the gut microbiota of offspring: Continuous high-dose SMZ exposure significantly decreased the relative abundance of Ligilactobacillus murinus, Limosilactobacillus reuteri, Lactobacillus johnsonii, and Bifidobacterium pseudolongum (p < 0.05) in female offspring mice; however, these significant changes were not observed in male offspring mice.

18.
Appl Environ Microbiol ; 90(3): e0207423, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38319094

RESUMO

Bifidobacterium breve, one of the main bifidobacterial species colonizing the human gastrointestinal tract in early life, has received extensive attention for its purported beneficial effects on human health. However, exploration of the mode of action of such beneficial effects exerted by B. breve is cumbersome due to the lack of effective genetic tools, which limits its synthetic biology application. The widespread presence of CRISPR-Cas systems in the B. breve genome makes endogenous CRISPR-based gene editing toolkits a promising tool. This study revealed that Type I-C CRISPR-Cas systems in B. breve can be divided into two groups based on the amino acid sequences encoded by cas gene clusters. Deletion of the gene coding uracil phosphoribosyl-transferase (upp) was achieved in five B. breve strains from both groups using this system. In addition, translational termination of uracil phosphoribosyl-transferase was successfully achieved in B. breve FJSWX38M7 by single-base substitution of the upp gene and insertion of three stop codons. The gene encoding linoleic acid isomerase (bbi) in B. breve, being a characteristic trait, was deleted after plasmid curing, which rendered it unable to convert linoleic acid into conjugated linoleic acid, demonstrating the feasibility of successive editing. This study expands the toolkit for gene manipulation in B. breve and provides a new approach toward functional genome editing and analysis of B. breve strains.IMPORTANCEThe lack of effective genetic tools for Bifidobacterium breve is an obstacle to studying the molecular mechanisms of its health-promoting effects, hindering the development of next-generation probiotics. Here, we introduce a gene editing method based on the endogenous CRISPR-Cas system, which can achieve gene deletion, single-base substitution, gene insertion, and successive gene editing in B. breve. This study will facilitate discovery of functional genes and elucidation of molecular mechanisms of B. breve pertaining to health-associated benefits.


Assuntos
Bifidobacterium breve , Sistemas CRISPR-Cas , Humanos , Edição de Genes/métodos , Bifidobacterium breve/genética , Ácido Linoleico , Transferases/genética , Uracila
19.
J Agric Food Chem ; 72(9): 4991-5002, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38346801

RESUMO

Brown discoloration was observed in the crust of commercial frozen steamed stuffed buns (FSSBs) during resteaming. Culture-dependent and culture-independent analyses demonstrated that Serratia marcescens, a prodigiosin-producing species, was more abundant in spoiled samples than in unspoiled samples. Inoculation of experimental FSSBs with S. marcescens isolated from spoiled FSSBs confirmed that this species causes brown discoloration of FSSBs during resteaming. S. marcescens formed prodigiosin only between 15 and 28 °C but brown discoloration appeared only upon resteaming after storage at 4 °C. High-performance liquid chromatography analyses revealed that prodigiosin was absent from yellow-brown FSSBs. The pigmentation observed during resteaming is thus likely attributable to the intermediate 2-methyl-3-amylpyrrole. These findings provide valuable insights into the microbial contamination of FSSBs and will facilitate the prevention of spoilage of FSSBs.


Assuntos
Prodigiosina , Serratia marcescens , Pigmentação , Congelamento
20.
Biomolecules ; 14(2)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38397477

RESUMO

The vaginal epithelial barrier, which integrates mechanical, immune, chemical, and microbial defenses, is pivotal in safeguarding against external pathogens and upholding the vaginal microecological equilibrium. Although the widely used metronidazole effectively curtails Gardnerella vaginalis, a key pathogen in bacterial vaginosis, it falls short in restoring the vaginal barrier or reducing recurrence rates. Our prior research highlighted Lactobacillus crispatus CCFM1339, a vaginally derived Lactobacillus strain, for its capacity to modulate the vaginal epithelial barrier. In cellular models, L. crispatus CCFM1339 fortified the integrity of the cellular monolayer, augmented cellular migration, and facilitated repair. Remarkably, in animal models, L. crispatus CCFM1339 substantially abated the secretion of the barrier disruption biomarker E-cadherin (from 101.45 to 82.90 pg/mL) and increased the anti-inflammatory cytokine IL-10 (35.18% vs. the model), consequently mitigating vaginal inflammation in mice. Immunological assays in vaginal tissues elucidated increased secretory IgA levels (from 405.56 to 740.62 ng/mL) and curtailed IL-17 gene expression. Moreover, L. crispatus CCFM1339 enhanced Lactobacilli abundance and attenuated Enterobacterium and Enterococcus within the vaginal microbiome, underscoring its potential in probiotic applications for vaginal barrier regulation.


Assuntos
Lactobacillus crispatus , Vaginose Bacteriana , Humanos , Feminino , Animais , Camundongos , Gardnerella vaginalis/genética , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/microbiologia , Vagina/microbiologia , Lactobacillus/metabolismo
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