To determine the genetic diversity and population structure of sweet potato accessions cultivated in China, and to establish the genetic relationships among their germplasm types, a representative collection of 240 ac...To determine the genetic diversity and population structure of sweet potato accessions cultivated in China, and to establish the genetic relationships among their germplasm types, a representative collection of 240 accessions was analyzed using inter-simple sequence repeat （ISSR） markers. The mean genetic similarity coefifcient, Nei’s gene diversity, and shared allele distance of tested sweet potato accessions were 0.7302, 0.3167 and 0.2698, respectively. The 240 accessions could be divided into six subgroups and ifve subpopulations based on neighbor-joining （NJ） clustering and STRUCTURE results, and obvious genetic relationships among the tested sweet potato accessions were identiifed. The marker-based NJ clustering and population structure showed no distinct assignment pattern corresponding to lfesh color or geographical ecotype of the tested sweet potato germplasm. Analysis of molecular variance （AMOVA） revealed small but signiifcant difference between white and orange-lfeshed sweet potato accessions. Small but signiifcant difference were also observed among sweet potato accessions from the Southern summer-autumn sweet potato region, the Yellow River Basin spring and summer sweet potato region and the Yangtze River Basin summer sweet potato region. This study demonstrates that genetic diversity in the tested sweet potato germplasm collection in China is lower than that in some reported sweet potato germplasm collections from other regions. Pedigree investigations suggest that more diverse Chinese sweet potato varieties should be formed by broadening the selection scope of breeding parents and incorporating the introduced varieties into future breeding programs.展开更多
Background Multiple sclerosis(MS)is an autoimmune,inflammatory demyelinating disease of the central nervous system(CNS)characterized by de-/remyelination,neuroinflammation and oligodendrocyte loss.Although a greater u...Background Multiple sclerosis(MS)is an autoimmune,inflammatory demyelinating disease of the central nervous system(CNS)characterized by de-/remyelination,neuroinflammation and oligodendrocyte loss.Although a greater understanding of MS have increased acquaintance of the pathogenesis and pathophysiology,the exploration of treatment is still challenging.Fasudil,one of the most thoroughly studied Rho kinase(ROCK)inhibitors,has been shown to have effects in neurodegenerative diseases.However,the effect of Fasudil on preventing the progression of the demyelination in MS has not been evaluated.Cuprizone(CPZ)-induced demyelination is a model used to study de-/remyelination in the CNS.Some aspects of the histological pattern induced by CPZ are similar to MS.The aim of the study is to investigate the effect of Fasudil on CPZ-induced demyelination,and to explore the mechanisms for the possible remyelination.Materials and Methods Male C57 BL/6 mice(10-12 weeks old)were assigned into normal group,fed a normal diet;CPZ group,fed CPZ and intraperitoneally(i.p.)injected with normal saline after 4 weeks for consecutive 2 weeks;Fasudil-treated CPZ group,which were i.p.injected with Fasudil(40 mg/kg/day)after 4 weeks for consecutive 2 weeks.All groups were assessed by Elevated plus-maze(EPM)test and Pole test at the end of the experiment.For examing the extent of demyelination,Luxol Fast Blue(LFB)staining,Black GoldⅡand myelin basic protein(MBP)immunohistochemistry staining were used for slides of brains.Splenic MNCs were fixed and stained with the following antibodies:Alexa Fluor B220,FITCCD4/PE-IFN-γ,FITC-CD4/PE-IL-17.At least 10,000 events were collected using flow cytometer.Results Following CPZ-exposure,mice presented a lower density of LFB,Black GoldⅡand MBP expression,loss of mature oligodendrocytes.Spleen atrophy was observed in CPZ-group compared to normal mice,and we firstly found that CPZ feeding induced the formation of MOG antibody.Fasudil treatment improved behavioral abnormality,promoted remyelination,inhibited spleen atrophy and production of MOG antibodies,prevented the infiltration of peripheral T cells,B cells,macrophages,and declined the neuroinflammation by inhibiting Iba1+iNOS+,Iba1+NF-κB+microglia.Fasudil treatment also reduced the levels of IL-1β,IL-6 and TNF-α.Discussion In this study,we demonstrated that demyelinating model was successfully established.Then we tested whether Fasudil plays a remyelinating role in this model.Spleen atrophy was observed after CPZ-feeding compared to normal mice.Previous studies have shown that splenic atrophy in experimental stroke may contribute to brain injury possibly through the release of inflammatory mediators and spleen-derived inflammatory cells to the circulation and migration into the brain,which aggravate the brain inflammatory response and led to secondary injure.At present,we lack direct evidence to elucidate the mechanisms for spleen atrophy in CPZ-induced demyelination.We firstly found that CPZ-feeding induced the formation of MOG antibody.Recent study indicated that BBB hyperpermeability precedes demyelination in CPZ-demyelinating model.Another study suggested that debris of damaged cells in the CNS may present as antigens after penetrating the BBB,giving rise to autoantibodies.Therefore,it is possible that the myelin debris produced the destruction of myelin sheath can enter the blood circulation and stimulate the immune response of T and B cells.We found that MOG antibody was elevated in the supernatant of cultured plenocytes,indicating that the MOG antibodies were derived from peripheral immune cells.Our results showed that the level of MOG antibody in the brain homogenate of CPZ-treated mice was higher than that of normal mice,suggesting that antibodies can enter brain tissue and anti a-synuclein antibody was negative,which indicate that anti MOG antibody is a specific antibody.In our study,MOG antibody was capable of being detected in the brain of CPZ-treated mice,providing a possibility for specific MOG antibody-mediated oligodendrocyte damage.CPZ induced a wide range of Iba-1+microglia,which was inhibited by Fasudil.These results suggest that the suppression of inflammatory microenvironment may contribute to the remyelination.In conclusion,the administration of Fasudil promoted remyelination by multiple mechanisms.展开更多
基金supported by the National Natural Science Foundation of China (31101192)the Animal and Plant Breeding Project of Chongqing,China (cstc2010AB1053)+2 种基金the Application Development Key Project of Chongqing,China (cstc2013yykfb80010)the Fundamental Research Funds for the Central Universities,China (XDJK2011C004)the "111" Project (B12006) of Ministry of Education,China
文摘To determine the genetic diversity and population structure of sweet potato accessions cultivated in China, and to establish the genetic relationships among their germplasm types, a representative collection of 240 accessions was analyzed using inter-simple sequence repeat （ISSR） markers. The mean genetic similarity coefifcient, Nei’s gene diversity, and shared allele distance of tested sweet potato accessions were 0.7302, 0.3167 and 0.2698, respectively. The 240 accessions could be divided into six subgroups and ifve subpopulations based on neighbor-joining （NJ） clustering and STRUCTURE results, and obvious genetic relationships among the tested sweet potato accessions were identiifed. The marker-based NJ clustering and population structure showed no distinct assignment pattern corresponding to lfesh color or geographical ecotype of the tested sweet potato germplasm. Analysis of molecular variance （AMOVA） revealed small but signiifcant difference between white and orange-lfeshed sweet potato accessions. Small but signiifcant difference were also observed among sweet potato accessions from the Southern summer-autumn sweet potato region, the Yellow River Basin spring and summer sweet potato region and the Yangtze River Basin summer sweet potato region. This study demonstrates that genetic diversity in the tested sweet potato germplasm collection in China is lower than that in some reported sweet potato germplasm collections from other regions. Pedigree investigations suggest that more diverse Chinese sweet potato varieties should be formed by broadening the selection scope of breeding parents and incorporating the introduced varieties into future breeding programs.
文摘Background Multiple sclerosis(MS)is an autoimmune,inflammatory demyelinating disease of the central nervous system(CNS)characterized by de-/remyelination,neuroinflammation and oligodendrocyte loss.Although a greater understanding of MS have increased acquaintance of the pathogenesis and pathophysiology,the exploration of treatment is still challenging.Fasudil,one of the most thoroughly studied Rho kinase(ROCK)inhibitors,has been shown to have effects in neurodegenerative diseases.However,the effect of Fasudil on preventing the progression of the demyelination in MS has not been evaluated.Cuprizone(CPZ)-induced demyelination is a model used to study de-/remyelination in the CNS.Some aspects of the histological pattern induced by CPZ are similar to MS.The aim of the study is to investigate the effect of Fasudil on CPZ-induced demyelination,and to explore the mechanisms for the possible remyelination.Materials and Methods Male C57 BL/6 mice(10-12 weeks old)were assigned into normal group,fed a normal diet;CPZ group,fed CPZ and intraperitoneally(i.p.)injected with normal saline after 4 weeks for consecutive 2 weeks;Fasudil-treated CPZ group,which were i.p.injected with Fasudil(40 mg/kg/day)after 4 weeks for consecutive 2 weeks.All groups were assessed by Elevated plus-maze(EPM)test and Pole test at the end of the experiment.For examing the extent of demyelination,Luxol Fast Blue(LFB)staining,Black GoldⅡand myelin basic protein(MBP)immunohistochemistry staining were used for slides of brains.Splenic MNCs were fixed and stained with the following antibodies:Alexa Fluor B220,FITCCD4/PE-IFN-γ,FITC-CD4/PE-IL-17.At least 10,000 events were collected using flow cytometer.Results Following CPZ-exposure,mice presented a lower density of LFB,Black GoldⅡand MBP expression,loss of mature oligodendrocytes.Spleen atrophy was observed in CPZ-group compared to normal mice,and we firstly found that CPZ feeding induced the formation of MOG antibody.Fasudil treatment improved behavioral abnormality,promoted remyelination,inhibited spleen atrophy and production of MOG antibodies,prevented the infiltration of peripheral T cells,B cells,macrophages,and declined the neuroinflammation by inhibiting Iba1+iNOS+,Iba1+NF-κB+microglia.Fasudil treatment also reduced the levels of IL-1β,IL-6 and TNF-α.Discussion In this study,we demonstrated that demyelinating model was successfully established.Then we tested whether Fasudil plays a remyelinating role in this model.Spleen atrophy was observed after CPZ-feeding compared to normal mice.Previous studies have shown that splenic atrophy in experimental stroke may contribute to brain injury possibly through the release of inflammatory mediators and spleen-derived inflammatory cells to the circulation and migration into the brain,which aggravate the brain inflammatory response and led to secondary injure.At present,we lack direct evidence to elucidate the mechanisms for spleen atrophy in CPZ-induced demyelination.We firstly found that CPZ-feeding induced the formation of MOG antibody.Recent study indicated that BBB hyperpermeability precedes demyelination in CPZ-demyelinating model.Another study suggested that debris of damaged cells in the CNS may present as antigens after penetrating the BBB,giving rise to autoantibodies.Therefore,it is possible that the myelin debris produced the destruction of myelin sheath can enter the blood circulation and stimulate the immune response of T and B cells.We found that MOG antibody was elevated in the supernatant of cultured plenocytes,indicating that the MOG antibodies were derived from peripheral immune cells.Our results showed that the level of MOG antibody in the brain homogenate of CPZ-treated mice was higher than that of normal mice,suggesting that antibodies can enter brain tissue and anti a-synuclein antibody was negative,which indicate that anti MOG antibody is a specific antibody.In our study,MOG antibody was capable of being detected in the brain of CPZ-treated mice,providing a possibility for specific MOG antibody-mediated oligodendrocyte damage.CPZ induced a wide range of Iba-1+microglia,which was inhibited by Fasudil.These results suggest that the suppression of inflammatory microenvironment may contribute to the remyelination.In conclusion,the administration of Fasudil promoted remyelination by multiple mechanisms.
