ProBiotic-4 is a probiotic preparation composed of Bifidobacterium lactis,Lactobacillus casei,Bifidobacterium bifidum,and Lactobacillus acidophilus.This study aims to investigate the effects of ProBiotic-4 on the micr...ProBiotic-4 is a probiotic preparation composed of Bifidobacterium lactis,Lactobacillus casei,Bifidobacterium bifidum,and Lactobacillus acidophilus.This study aims to investigate the effects of ProBiotic-4 on the microbiota-gut-brain axis and cognitive deficits,and to explore the underlying molecular mechanism using senescence-accelerated mouse prone 8(SAMP8)mice.ProBiotic-4 was orally administered to 9-month-old SAMP8 mice for 12 weeks.We observed that ProBiotic-4 significantly improved the memory deficits,cerebral neuronal and synaptic injuries,glial activation,and microbiota composition in the feces and brains of aged SAMP8 mice.ProBiotic-4 substantially attenuated aging-related disruption of the intestinal barrier and blood-brain barrier,decreased interleukin-6 and tumor necrosis factor-αat both mRNA and protein levels,reduced plasma and cerebral lipopolysaccharide(LPS)concentration,toll-like receptor 4(TLR4)expression,and nuclear factor-κB(NF-κB)nuclear translocation in the brain.In addition,not only did ProBiotic-4 significantly decreased the levels ofγ-H2 AX,8-hydroxydesoxyguanosine,and retinoic-acid-inducible gene-I(RIG-I),it also abrogated RIG-I multimerization in the brain.These findings suggest that targeting gut microbiota with probiotics may have a therapeutic potential for the deficits of the microbiota-gut-brain axis and cognitive function in aging,and that its mechanism is associated with inhibition of both TLR4-and RIG-I-mediated NF-κB signaling pathway and inflammatory responses.展开更多
The endosomal Toll-like receptors （TLRs） TLR3, TLR7, TLR8 and TLR9 are important in sensing foreign nucleic acids encountered by phagocytes. Because TLR8 was initially thought to be non-functional in mice, less is k...The endosomal Toll-like receptors （TLRs） TLR3, TLR7, TLR8 and TLR9 are important in sensing foreign nucleic acids encountered by phagocytes. Because TLR8 was initially thought to be non-functional in mice, less is known about TLR8 than the genetically and functionally related TLR7. Originally associated with the recognition of single-stranded RNA of viral origin, there is now evidence that human TLR8 is also able to sense bacterial RNA released within phagosomal vacuoles, inducing the production of both nuclear factor （NF）-κB-dependent cytokines and type I interferons （IFNs）, such as IFN-β. The functions of TLR8 extend beyond the recognition of foreign pathogens and include cross-talk with other endosomal TLRs, a process that may also have a role in the generation of autoimmunity.展开更多
基金supported by the National Natural Science Foundation of China(81473219 and 81973307)partly by 111 Project of the National Ministry of Education(B18035,China).
文摘ProBiotic-4 is a probiotic preparation composed of Bifidobacterium lactis,Lactobacillus casei,Bifidobacterium bifidum,and Lactobacillus acidophilus.This study aims to investigate the effects of ProBiotic-4 on the microbiota-gut-brain axis and cognitive deficits,and to explore the underlying molecular mechanism using senescence-accelerated mouse prone 8(SAMP8)mice.ProBiotic-4 was orally administered to 9-month-old SAMP8 mice for 12 weeks.We observed that ProBiotic-4 significantly improved the memory deficits,cerebral neuronal and synaptic injuries,glial activation,and microbiota composition in the feces and brains of aged SAMP8 mice.ProBiotic-4 substantially attenuated aging-related disruption of the intestinal barrier and blood-brain barrier,decreased interleukin-6 and tumor necrosis factor-αat both mRNA and protein levels,reduced plasma and cerebral lipopolysaccharide(LPS)concentration,toll-like receptor 4(TLR4)expression,and nuclear factor-κB(NF-κB)nuclear translocation in the brain.In addition,not only did ProBiotic-4 significantly decreased the levels ofγ-H2 AX,8-hydroxydesoxyguanosine,and retinoic-acid-inducible gene-I(RIG-I),it also abrogated RIG-I multimerization in the brain.These findings suggest that targeting gut microbiota with probiotics may have a therapeutic potential for the deficits of the microbiota-gut-brain axis and cognitive function in aging,and that its mechanism is associated with inhibition of both TLR4-and RIG-I-mediated NF-κB signaling pathway and inflammatory responses.
文摘The endosomal Toll-like receptors （TLRs） TLR3, TLR7, TLR8 and TLR9 are important in sensing foreign nucleic acids encountered by phagocytes. Because TLR8 was initially thought to be non-functional in mice, less is known about TLR8 than the genetically and functionally related TLR7. Originally associated with the recognition of single-stranded RNA of viral origin, there is now evidence that human TLR8 is also able to sense bacterial RNA released within phagosomal vacuoles, inducing the production of both nuclear factor （NF）-κB-dependent cytokines and type I interferons （IFNs）, such as IFN-β. The functions of TLR8 extend beyond the recognition of foreign pathogens and include cross-talk with other endosomal TLRs, a process that may also have a role in the generation of autoimmunity.
