Parkinson’s disease is characterized by synucleinopathy-associated neurodegeneration.Previous studies have shown that glucagon-like peptide-1(GLP-1)has beneficial effects in a mouse model of Parkinson’s disease indu...Parkinson’s disease is characterized by synucleinopathy-associated neurodegeneration.Previous studies have shown that glucagon-like peptide-1(GLP-1)has beneficial effects in a mouse model of Parkinson’s disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.However,the effect of GLP-1 on intrinsic synuclein malfunction remains unclear.In this study,we investigated the effect of Lactococcus lactis MG1363-pMG36e-GLP-1 on parkinsonism in SncaA53T transgenic mice and explored the underlying mechanisms.Our data showed that Lactococcus lactis MG1363-pMG36e-GLP-1 inhibited dopaminergic neuronal death,reduced pathological aggregation ofα-synuclein,and decreased movement disorders in SncaA53T transgenic mice.Furthermore,Lactococcus lactis MG1363-pMG36e-GLP-1 downregulated lipopolysaccharide-related inflammation,reduced cerebral activation of microglia and astrocytes,and promoted cell survival via the GLP-1 receptor/PI3K/Akt pathway in the substantia nigra.Additionally,Lactococcus lactis MG1363-pMG36e-GLP-1 decreased serum levels of pro-inflammatory molecules including lipopolysaccharide,lipopolysaccharide binding protein,interleukin-1β,and interleukin-6.Gut histopathology and western blotting further revealed that Lactococcus lactis MG1363-pMG36e-GLP-1 increased the expression of gut integrity-related proteins and reduced lipopolysaccharide-related inflammation by reversing gut dysbiosis in SncaA53T transgenic mice.Our findings showed that the beneficial effect of Lactococcus lactis MG1363-pMG36e-GLP-1 on parkinsonism traits in SncaA53T transgenic mice is mediated by microglial polarization and the reversal of dysbiosis.Collectively,our findings suggest that Lactococcus lactis MG1363-pMG36e-GLP-1 is a promising therapeutic agent for the treatment of Parkinson’s disease.展开更多
Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by g...Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by genetic factors but also by en-vironmental factors,particularly the symbiotic microbiota.Bifidobacterium animalis subsp.lactis(BB-12),originally found in dairy products,is widely used in infant for-mula and dietary supplements.However,its role and mechanisms in immune develop-ment during early life remain unclear.Methods:Using GF mice as the experimental model,B.animalis subsp.lactis BB-12 was administered via gavage during early life.In the juvenile stage,changes in T-cell subsets in the spleen,thymus,and gut intraepithelial lymphocytes(IEL)were assessed using spectral flow cytometry.Additionally,targeted metabolomics analysis of trypto-phan metabolism and short-chain fatty acid pathways in colonic tissue was conducted to explore how B.animalis subsp.lactis BB-12 influences the immune system through gut microbiota metabolism.Results:BB-12 effectively modulates the gut immune microenvironment,leading to beneficial changes in T-cell subsets in key immune tissues such as the spleen,thymus,and gut IELs.Metabolomics analysis further supports these findings by showing that BB-12 intervention greatly increased the production of tryptophan derivatives and acetic acid in the colon of GF mice.Conclusion:The findings provide theoretical evidence for the role of B.animalis subsp.lactis in immune system development and support its application in dietary supple-ments,suggesting potential as a component for infant immune health and in prevent-ing immune-related diseases.展开更多
Salmonella grows better under aerobic conditions as a facultative anaerobic foodborne pathogenic bacteria.The oxygen-scavenging activity of Lactococcus lactis in the intestinal tract is a promising strategy for preven...Salmonella grows better under aerobic conditions as a facultative anaerobic foodborne pathogenic bacteria.The oxygen-scavenging activity of Lactococcus lactis in the intestinal tract is a promising strategy for preventing Salmonella infection.In this study,the aerobic respiration requirement and preventive mechanism of L.lactis subsp.lactis KLDS 4.0325 in murine models infected by Salmonella enterica subsp.enterica serovar Typhimurium(S.Typhimurium)SL1344 were investigated.Results indicate that L.lactis KLDS 4.0325 is capable of aerobic respiratory metabolism in the host intestine when exogenous heme exists,and decrease intestinal oxygen concentration,which in turn trigger autophagy of intestinal cells to reduce S.Typhimurium load,improve gut microbiota composition,alleviate intestinal barrier injury and inflammation response.These results suggest that aerobic respiration L.lactis KLDS 4.0325 can prevent S.Typhimurium infection in a new way in which by restoring intestinal cell hypoxia,maintaining immune balance and regulating intestinal flora.展开更多
Lactococcus lactis,a major starter culture in the dairy industry,has been widely applied in food fermentation.While current research has primarily focused on evaluating its role during fermentation,genomic investigati...Lactococcus lactis,a major starter culture in the dairy industry,has been widely applied in food fermentation.While current research has primarily focused on evaluating its role during fermentation,genomic investigations into its genetic diversity and functional adaptability remain limited.In this study,199 L.lactis strains isolated from Chinese traditional artisanal cheeses(72 bovine,71 goat,and 56 yak milk cheese isolates)were subjected to comparative genomic analysis.Genomic characteristic analysis indicated that bovine milk strains possess larger genomes and the highest number of unique genes.Functional characterization further demonstrated notable differences in carbohydrate metabolism among strains from different sources,with yak milk strains enriched in enzymes involved in complex polysaccharide degradation,including members of the carbohydrate esterases family.Moreover,strains from different sources exhibit distinct strategies for lactose hydrolysis and metabolic utilization,reflecting adaptive evolution to their specific nutritional niches.Analysis of the antibiotic resistance profile suggests that L.lactis predominantly harbors glycopeptide and lincosamide resistance genes,encompassing four distinct resistance mechanisms.Collectively,this study reveals the genetic diversity and adaptive evolution of L.lactis strains from different sources and identifies key genes associated with carbohydrate degradation,lactose metabolism,and antibiotic resistance,providing concrete genetic evidence for the selection of efficient and safe industrial fermentation strains.展开更多
[Objective]The aim was to clone TapⅡchalcone isomerases(CHI1 A) from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone i...[Objective]The aim was to clone TapⅡchalcone isomerases(CHI1 A) from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone isomerases(CHI1 A) was cloned by RTPCR method,and it was sequenced after cloning into pMD18-T vectors,and recombined to expression vector PNZ8149-CHI1 A,then it was transformed into Lactococcus Lactis NZ3900[Result]The sequencing results indicated that the cloned fragment of CHI1 A contained 670 nucleotides,and shared a sequence homology of 92% with that from Genbank accession number AF595413(CHI1 A).CHI1 A was transformed into NICE expression system successfully by identification of PCR and digestion.[Conclusion]The foundation of using the microorganism fermentation method to produce flavonoids was laid by construction of efficient induction expression vector with chalcone isomerases CHI1 A.展开更多
[Objective]In order to improve expression vector of L.lactis at food grade and widen application range of original system.[Method] Taking pNZ8149 as basis,the promoter PnisA of pNZ8149 was inserted L.lactis MG1363 and...[Objective]In order to improve expression vector of L.lactis at food grade and widen application range of original system.[Method] Taking pNZ8149 as basis,the promoter PnisA of pNZ8149 was inserted L.lactis MG1363 and SPusp45 of unknown secretory protein in downstream.Through PCR technology,specific primers were used to delete restriction sites between promoter sequence and signal peptide gene sequence and ensure better distance between SD sequence and start codon to construct secreting expression vector pNZS.The reporter gene gus was recombined into multiple cloning site of pNZS to construct pNZS-gus and L.lactis was transformed by electroporation.10 ng/ml nisin was used for induction culture,then culture solution was conducted GUS staining test.[Result]The new constructed L.lactis N3900/pNZS-gus system could express active GUS protein and GUS protein could be secreted out of cell.[Conclusion]The successful construction of this system lays foundation for secretion expression study of protein and oral vaccine research.展开更多
【目的】寻找精氨酸代谢途径中与酸胁迫相关的关键作用因素。【方法】通过在Lactococcus lactis NZ9000中分别过量表达来源于Lactobacillus casei Zhang的精氨酰琥珀酸合成酶(ASS)和精氨酰琥珀酸裂解酶(ASL)改变精氨酸代谢提高酸胁迫抗...【目的】寻找精氨酸代谢途径中与酸胁迫相关的关键作用因素。【方法】通过在Lactococcus lactis NZ9000中分别过量表达来源于Lactobacillus casei Zhang的精氨酰琥珀酸合成酶(ASS)和精氨酰琥珀酸裂解酶(ASL)改变精氨酸代谢提高酸胁迫抗性。【结果】与对照菌株对比,重组菌株在环境胁迫下表现了较高的生长性能、存活率和发酵性能。生理学分析发现,酸胁迫环境下,重组菌株细胞有较高的胞内NH4+、ATP含量和H+-ATPase活性,并显著提高了精氨酸脱亚胺酶(ADI)途径中的氨基酸浓度。进一步的转录分析发现,天冬氨酸合成、精氨酸代谢相关的基因转录水平上调。【结论】在L.lactis NZ9000中过量表达ASS或ASL可以引发精氨酸代谢流量的上调,进而提高了细胞的多种胁迫抗性。精氨酸合成途径广泛存在于多种微生物中,为微生物,尤其是工业微生物提高胁迫抗性提供了新思路。展开更多
AIM: To investigate the effect of a fermented milk containing Bifidobacterium lactis DN-173010 and yogurt strains (BIO) on adult women with constipation in Beijing.METHODS: A total of 135 adult females with constipati...AIM: To investigate the effect of a fermented milk containing Bifidobacterium lactis DN-173010 and yogurt strains (BIO) on adult women with constipation in Beijing.METHODS: A total of 135 adult females with constipation were randomly allocated to consume for 2 wk either 100 g of the test fermented milk or 100 g of an acidified milk containing non-living bacteria (control).Stool frequency,defecation condition scores,stool consistency and food intake were recorded at baseline and after 1 and 2 wk in an intention-to-treat population of 126 subjects.In parallel,safety evaluation parameters were performed.RESULTS: At baseline,no differences were found between groups.Following consumption of test product,stool frequency was significantly increased after 1 wk (3.5 ± 1.5 vs 2.4 ± 0.6,P < 0.01) and 2 wk (4.1 ± 1.7 vs 2.4 ± 0.6,P < 0.01),vs baseline.Similarly,after 1 and 2 wk,of test product consumption,defecation condition (1.1 ± 0.9 vs 1.9 ± 1.2,P < 0.01 and 0.8 ± 1.0 vs 1.9 ± 1.2,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.5 ± 1.1,P < 0.01 and 0.6 ± 0.8 vs 1.5 ± 1.1,P < 0.01,respectively) were significantly improved.Compared with the control group,stool frequency was also significantly increased (3.5 ± 1.5 vs 2.5 ± 0.9,P < 0.01 and 4.1 ± 1.7 vs 2.6 ± 1.0,P < 0.01,respectively),and defecation condition (1.1 ± 0.9 vs 1.6 ± 1.1,P < 0.01 and 0.8 ± 1.0 vs 1.6 ± 1.1,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.4 ± 1.0,P < 0.05 and 0.6 ± 0.8 vs 1.3 ± 1.0,P < 0.01,respectively) significantly decreased after 1 and 2 wk of product consumption.During the same period,food intake did not change between the two groups,and safety parameters of the subjects were within normal ranges.CONCLUSION: This study suggests a beneficial effect of a fermented milk containing B.lactis DN-173010 on stool frequency,defecation condition and stool consistency in adult women with constipation constipated women after 1 and 2 wk of consumption.展开更多
基金supported by grants from the Jiangxi Provincial Natural Science Foundation,No.20242BAB26134(to XF)the National Natural Science Foundation of China,Nos.82060638(to TC),82060222(to XF),82460237(to XF)+1 种基金the Major Disciplines of Academic and Technical Leaders Project of Jiangxi Province,Nos.20194BCJ22032(to TC),20213BCJL22049(to XF)Science and Technology Plan of Jiangxi Health Planning Committee,No.202210390(to XF).
文摘Parkinson’s disease is characterized by synucleinopathy-associated neurodegeneration.Previous studies have shown that glucagon-like peptide-1(GLP-1)has beneficial effects in a mouse model of Parkinson’s disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.However,the effect of GLP-1 on intrinsic synuclein malfunction remains unclear.In this study,we investigated the effect of Lactococcus lactis MG1363-pMG36e-GLP-1 on parkinsonism in SncaA53T transgenic mice and explored the underlying mechanisms.Our data showed that Lactococcus lactis MG1363-pMG36e-GLP-1 inhibited dopaminergic neuronal death,reduced pathological aggregation ofα-synuclein,and decreased movement disorders in SncaA53T transgenic mice.Furthermore,Lactococcus lactis MG1363-pMG36e-GLP-1 downregulated lipopolysaccharide-related inflammation,reduced cerebral activation of microglia and astrocytes,and promoted cell survival via the GLP-1 receptor/PI3K/Akt pathway in the substantia nigra.Additionally,Lactococcus lactis MG1363-pMG36e-GLP-1 decreased serum levels of pro-inflammatory molecules including lipopolysaccharide,lipopolysaccharide binding protein,interleukin-1β,and interleukin-6.Gut histopathology and western blotting further revealed that Lactococcus lactis MG1363-pMG36e-GLP-1 increased the expression of gut integrity-related proteins and reduced lipopolysaccharide-related inflammation by reversing gut dysbiosis in SncaA53T transgenic mice.Our findings showed that the beneficial effect of Lactococcus lactis MG1363-pMG36e-GLP-1 on parkinsonism traits in SncaA53T transgenic mice is mediated by microglial polarization and the reversal of dysbiosis.Collectively,our findings suggest that Lactococcus lactis MG1363-pMG36e-GLP-1 is a promising therapeutic agent for the treatment of Parkinson’s disease.
基金supported by the National Key R&D Programs of China(2022YFF0710701,2022YFF0710702)Guangzhou Key Research and Development Program(202206010157)+2 种基金Guangzhou Joint Fund for Key Laboratory(202201020381)Medical Joint Fund of Jinan University(YXJC202204)Open Research Project of the Key Laboratory of Viral Pathogenesis and Infection Prevention and Control of the Ministry of Education(2023VPPC-R02).
文摘Background:The maturation of the immune system is critical during early life,as it involves the differentiation,maturation,and establishment of immune tolerance of immune cells.This process is influenced not only by genetic factors but also by en-vironmental factors,particularly the symbiotic microbiota.Bifidobacterium animalis subsp.lactis(BB-12),originally found in dairy products,is widely used in infant for-mula and dietary supplements.However,its role and mechanisms in immune develop-ment during early life remain unclear.Methods:Using GF mice as the experimental model,B.animalis subsp.lactis BB-12 was administered via gavage during early life.In the juvenile stage,changes in T-cell subsets in the spleen,thymus,and gut intraepithelial lymphocytes(IEL)were assessed using spectral flow cytometry.Additionally,targeted metabolomics analysis of trypto-phan metabolism and short-chain fatty acid pathways in colonic tissue was conducted to explore how B.animalis subsp.lactis BB-12 influences the immune system through gut microbiota metabolism.Results:BB-12 effectively modulates the gut immune microenvironment,leading to beneficial changes in T-cell subsets in key immune tissues such as the spleen,thymus,and gut IELs.Metabolomics analysis further supports these findings by showing that BB-12 intervention greatly increased the production of tryptophan derivatives and acetic acid in the colon of GF mice.Conclusion:The findings provide theoretical evidence for the role of B.animalis subsp.lactis in immune system development and support its application in dietary supple-ments,suggesting potential as a component for infant immune health and in prevent-ing immune-related diseases.
基金supported by the National Natural Science Foundation of China(32072190 and 32101929)Academic Backbone Plan of Northeast Agricultural University(20XG12)。
文摘Salmonella grows better under aerobic conditions as a facultative anaerobic foodborne pathogenic bacteria.The oxygen-scavenging activity of Lactococcus lactis in the intestinal tract is a promising strategy for preventing Salmonella infection.In this study,the aerobic respiration requirement and preventive mechanism of L.lactis subsp.lactis KLDS 4.0325 in murine models infected by Salmonella enterica subsp.enterica serovar Typhimurium(S.Typhimurium)SL1344 were investigated.Results indicate that L.lactis KLDS 4.0325 is capable of aerobic respiratory metabolism in the host intestine when exogenous heme exists,and decrease intestinal oxygen concentration,which in turn trigger autophagy of intestinal cells to reduce S.Typhimurium load,improve gut microbiota composition,alleviate intestinal barrier injury and inflammation response.These results suggest that aerobic respiration L.lactis KLDS 4.0325 can prevent S.Typhimurium infection in a new way in which by restoring intestinal cell hypoxia,maintaining immune balance and regulating intestinal flora.
基金supported by the National Key Research and Development Project(2022YFD2100703)the National Natural Science Foundation of China(32394051 and U23A20259)the Fundamental Research Funds for the Central Universities(JUSRP622013).
文摘Lactococcus lactis,a major starter culture in the dairy industry,has been widely applied in food fermentation.While current research has primarily focused on evaluating its role during fermentation,genomic investigations into its genetic diversity and functional adaptability remain limited.In this study,199 L.lactis strains isolated from Chinese traditional artisanal cheeses(72 bovine,71 goat,and 56 yak milk cheese isolates)were subjected to comparative genomic analysis.Genomic characteristic analysis indicated that bovine milk strains possess larger genomes and the highest number of unique genes.Functional characterization further demonstrated notable differences in carbohydrate metabolism among strains from different sources,with yak milk strains enriched in enzymes involved in complex polysaccharide degradation,including members of the carbohydrate esterases family.Moreover,strains from different sources exhibit distinct strategies for lactose hydrolysis and metabolic utilization,reflecting adaptive evolution to their specific nutritional niches.Analysis of the antibiotic resistance profile suggests that L.lactis predominantly harbors glycopeptide and lincosamide resistance genes,encompassing four distinct resistance mechanisms.Collectively,this study reveals the genetic diversity and adaptive evolution of L.lactis strains from different sources and identifies key genes associated with carbohydrate degradation,lactose metabolism,and antibiotic resistance,providing concrete genetic evidence for the selection of efficient and safe industrial fermentation strains.
文摘[Objective]The aim was to clone TapⅡchalcone isomerases(CHI1 A) from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone isomerases(CHI1 A) was cloned by RTPCR method,and it was sequenced after cloning into pMD18-T vectors,and recombined to expression vector PNZ8149-CHI1 A,then it was transformed into Lactococcus Lactis NZ3900[Result]The sequencing results indicated that the cloned fragment of CHI1 A contained 670 nucleotides,and shared a sequence homology of 92% with that from Genbank accession number AF595413(CHI1 A).CHI1 A was transformed into NICE expression system successfully by identification of PCR and digestion.[Conclusion]The foundation of using the microorganism fermentation method to produce flavonoids was laid by construction of efficient induction expression vector with chalcone isomerases CHI1 A.
基金Supported by Doctoral Fund of Jilin Agricultural University(20070193005)~~
文摘[Objective]In order to improve expression vector of L.lactis at food grade and widen application range of original system.[Method] Taking pNZ8149 as basis,the promoter PnisA of pNZ8149 was inserted L.lactis MG1363 and SPusp45 of unknown secretory protein in downstream.Through PCR technology,specific primers were used to delete restriction sites between promoter sequence and signal peptide gene sequence and ensure better distance between SD sequence and start codon to construct secreting expression vector pNZS.The reporter gene gus was recombined into multiple cloning site of pNZS to construct pNZS-gus and L.lactis was transformed by electroporation.10 ng/ml nisin was used for induction culture,then culture solution was conducted GUS staining test.[Result]The new constructed L.lactis N3900/pNZS-gus system could express active GUS protein and GUS protein could be secreted out of cell.[Conclusion]The successful construction of this system lays foundation for secretion expression study of protein and oral vaccine research.
基金Danone (Shanghai) Consulting Co.Ltd115 national science and technology program
文摘AIM: To investigate the effect of a fermented milk containing Bifidobacterium lactis DN-173010 and yogurt strains (BIO) on adult women with constipation in Beijing.METHODS: A total of 135 adult females with constipation were randomly allocated to consume for 2 wk either 100 g of the test fermented milk or 100 g of an acidified milk containing non-living bacteria (control).Stool frequency,defecation condition scores,stool consistency and food intake were recorded at baseline and after 1 and 2 wk in an intention-to-treat population of 126 subjects.In parallel,safety evaluation parameters were performed.RESULTS: At baseline,no differences were found between groups.Following consumption of test product,stool frequency was significantly increased after 1 wk (3.5 ± 1.5 vs 2.4 ± 0.6,P < 0.01) and 2 wk (4.1 ± 1.7 vs 2.4 ± 0.6,P < 0.01),vs baseline.Similarly,after 1 and 2 wk,of test product consumption,defecation condition (1.1 ± 0.9 vs 1.9 ± 1.2,P < 0.01 and 0.8 ± 1.0 vs 1.9 ± 1.2,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.5 ± 1.1,P < 0.01 and 0.6 ± 0.8 vs 1.5 ± 1.1,P < 0.01,respectively) were significantly improved.Compared with the control group,stool frequency was also significantly increased (3.5 ± 1.5 vs 2.5 ± 0.9,P < 0.01 and 4.1 ± 1.7 vs 2.6 ± 1.0,P < 0.01,respectively),and defecation condition (1.1 ± 0.9 vs 1.6 ± 1.1,P < 0.01 and 0.8 ± 1.0 vs 1.6 ± 1.1,P < 0.01,respectively) and stool consistency (1.0 ± 0.8 vs 1.4 ± 1.0,P < 0.05 and 0.6 ± 0.8 vs 1.3 ± 1.0,P < 0.01,respectively) significantly decreased after 1 and 2 wk of product consumption.During the same period,food intake did not change between the two groups,and safety parameters of the subjects were within normal ranges.CONCLUSION: This study suggests a beneficial effect of a fermented milk containing B.lactis DN-173010 on stool frequency,defecation condition and stool consistency in adult women with constipation constipated women after 1 and 2 wk of consumption.