Continuous spermatogenesis depends on the self-renewal and differentiation of spermatogonial stem cells(SSCs).SSCs,the only male reproductive stem cells that transmit genetic material to subsequent generations,possess...Continuous spermatogenesis depends on the self-renewal and differentiation of spermatogonial stem cells(SSCs).SSCs,the only male reproductive stem cells that transmit genetic material to subsequent generations,possess an inherent self-renewal ability,which allows the maintenance of a steady stem cell pool.SSCs eventually differentiate to produce sperm.However,in an in vitro culture system,SSCs can be induced to differentiate into various types of germ cells.Rodent SSCs are well defined,and a culture system has been successfully established for them.In contrast,available information on the biomolecular markers and a culture system for livestock SSCs is limited.This review summarizes the existing knowledge and research progress regarding mammalian SSCs to determine the mammalian spermatogenic process,the biology and niche of SSCs,the isolation and culture systems of SSCs,and the biomolecular markers and identification of SSCs.This information can be used for the effective utilization of SSCs in reproductive technologies for large livestock animals,enhancement of human male fertility,reproductive medicine,and protection of endangered species.展开更多
Main observation and conclusion Quassinoids,a class of highly oxygenated triterpenes,have been isolated as bitter principles from the plants of Simaroubaceae family.Five new quassinoids,chouchunlactone A-E(1-5),and tw...Main observation and conclusion Quassinoids,a class of highly oxygenated triterpenes,have been isolated as bitter principles from the plants of Simaroubaceae family.Five new quassinoids,chouchunlactone A-E(1-5),and two known ones were identified from the root barks of Ailanthus altissima Swingle(Simaroubaceae).The chemical structures of the new compounds were deduced by spectroscopic data analyses,NMR calculations and DP4+probability analysis.The absolute configurations were defined by comparison of their experimental and calculated electronic circular dichroism(ECD)spectra data,and compounds 1-2 were further confirmed by single-crystal X-ray diffraction.Biologically,compound 5 showed potencies equivalent to sorafenib(IC50 value,9.70μmol·L–1)against HepG2 cells.The Hoechst 33342 staining,JC-1 fluorescent dye and Annexin V/PI analysis studies demonstrated that 5 can induce apoptosis and attenuate mitochondrial membrane potential(MMP)in HepG2 cells.展开更多
基金This work was supported by the National Natural Science Foundation of China(No.31672425).
文摘Continuous spermatogenesis depends on the self-renewal and differentiation of spermatogonial stem cells(SSCs).SSCs,the only male reproductive stem cells that transmit genetic material to subsequent generations,possess an inherent self-renewal ability,which allows the maintenance of a steady stem cell pool.SSCs eventually differentiate to produce sperm.However,in an in vitro culture system,SSCs can be induced to differentiate into various types of germ cells.Rodent SSCs are well defined,and a culture system has been successfully established for them.In contrast,available information on the biomolecular markers and a culture system for livestock SSCs is limited.This review summarizes the existing knowledge and research progress regarding mammalian SSCs to determine the mammalian spermatogenic process,the biology and niche of SSCs,the isolation and culture systems of SSCs,and the biomolecular markers and identification of SSCs.This information can be used for the effective utilization of SSCs in reproductive technologies for large livestock animals,enhancement of human male fertility,reproductive medicine,and protection of endangered species.
基金This work was financially supported by the National Natural Science Foundation of China(No.81872767)the Career Development Support Plan for the Young and Middle-aged Teachers in Shenyang Pharmaceutical University(No.ZQN2018006)+1 种基金the Pro ject funded by China Postdoctoral Science Foundation(No.2020M680987)the Project of Innovation Team(No.LT2015027)of Liaoning in China.
文摘Main observation and conclusion Quassinoids,a class of highly oxygenated triterpenes,have been isolated as bitter principles from the plants of Simaroubaceae family.Five new quassinoids,chouchunlactone A-E(1-5),and two known ones were identified from the root barks of Ailanthus altissima Swingle(Simaroubaceae).The chemical structures of the new compounds were deduced by spectroscopic data analyses,NMR calculations and DP4+probability analysis.The absolute configurations were defined by comparison of their experimental and calculated electronic circular dichroism(ECD)spectra data,and compounds 1-2 were further confirmed by single-crystal X-ray diffraction.Biologically,compound 5 showed potencies equivalent to sorafenib(IC50 value,9.70μmol·L–1)against HepG2 cells.The Hoechst 33342 staining,JC-1 fluorescent dye and Annexin V/PI analysis studies demonstrated that 5 can induce apoptosis and attenuate mitochondrial membrane potential(MMP)in HepG2 cells.
