Most hematopoietic stem progenitor cells (HSPCs) reside in bone marrow (BM), but a small amount of HSPCs have been found to circulate between BM and tissues through blood and lymph. Several lines of evidence suggest t...Most hematopoietic stem progenitor cells (HSPCs) reside in bone marrow (BM), but a small amount of HSPCs have been found to circulate between BM and tissues through blood and lymph. Several lines of evidence suggest that sphingosine-1-phosphate (S1P) gradient triggers HSPC egression to blood circulation after mobilization from BM stem cell niches. Stem cells also visit certain tissues. After a temporary 36 h short stay in local tissues, HSPCs go to lymph in response to S1P gradient between lymph and tissue and eventually enter the blood circulation. S1P also has a role in the guidance of the primitive HSPCs homing to BM in vivo, as S1P analogue FTY720 treatment can improve HSPC BM homing and engraftment. In stress conditions, various stem cells or progenitor cells can be attracted to local injured tissues and participate in local tissue cell differentiation and tissue rebuilding through modulation the expression level of S1P1, S1P2 or S1P3 receptors. Hence, S1P is important for stem cells circulation in blood system to accomplish its role in body surveillance and injury recovery.展开更多
目的:探讨1-磷酸鞘氨醇(S1P)不同受体亚型(S1P1、S1P2、S1P3)在大鼠心肌梗死后心室重塑过程中的变化差异。方法:通过结扎大鼠左冠状动脉前降支,建立大鼠心肌梗死模型,在心肌梗死后1、4、8周,采用实时荧光定量PCR的方法,分别检测心脏非...目的:探讨1-磷酸鞘氨醇(S1P)不同受体亚型(S1P1、S1P2、S1P3)在大鼠心肌梗死后心室重塑过程中的变化差异。方法:通过结扎大鼠左冠状动脉前降支,建立大鼠心肌梗死模型,在心肌梗死后1、4、8周,采用实时荧光定量PCR的方法,分别检测心脏非梗死区、梗死区、正常对照心肌组织S1P1、S1P2、S1P3的m RNA相对表达。结果:心梗后心室重塑阶段,S1P1 m RNA的表达水平在非梗死区与梗死区的下降程度不一致,1周组非梗死区与正常对照组比较无统计学差异,而在梗死区2组间差异有统计学意义(P<0.05),在梗死区降低趋势更为明显。S1P2 m RNA在术后各组的非梗死区与正常对照心肌之间的表达比较,变化无统计学意义,且各时间点之间无差异,而在梗死区其表达变化较为显著(P<0.01)。S1P3 m RNA在心梗后1周表达显著增强(P<0.01),4周表达出现降低,这种表达抑制在梗死区更为明显(P<0.01和P<0.05)。结论:心室重塑阶段的S1P1、S1P2、S1P3 m RNA表达在非梗死区与梗死区变化不同步且各有特点,这种差异表达可能在心肌梗死后心室重塑过程中有重要意义。展开更多
文摘Most hematopoietic stem progenitor cells (HSPCs) reside in bone marrow (BM), but a small amount of HSPCs have been found to circulate between BM and tissues through blood and lymph. Several lines of evidence suggest that sphingosine-1-phosphate (S1P) gradient triggers HSPC egression to blood circulation after mobilization from BM stem cell niches. Stem cells also visit certain tissues. After a temporary 36 h short stay in local tissues, HSPCs go to lymph in response to S1P gradient between lymph and tissue and eventually enter the blood circulation. S1P also has a role in the guidance of the primitive HSPCs homing to BM in vivo, as S1P analogue FTY720 treatment can improve HSPC BM homing and engraftment. In stress conditions, various stem cells or progenitor cells can be attracted to local injured tissues and participate in local tissue cell differentiation and tissue rebuilding through modulation the expression level of S1P1, S1P2 or S1P3 receptors. Hence, S1P is important for stem cells circulation in blood system to accomplish its role in body surveillance and injury recovery.
文摘目的:探讨1-磷酸鞘氨醇(S1P)不同受体亚型(S1P1、S1P2、S1P3)在大鼠心肌梗死后心室重塑过程中的变化差异。方法:通过结扎大鼠左冠状动脉前降支,建立大鼠心肌梗死模型,在心肌梗死后1、4、8周,采用实时荧光定量PCR的方法,分别检测心脏非梗死区、梗死区、正常对照心肌组织S1P1、S1P2、S1P3的m RNA相对表达。结果:心梗后心室重塑阶段,S1P1 m RNA的表达水平在非梗死区与梗死区的下降程度不一致,1周组非梗死区与正常对照组比较无统计学差异,而在梗死区2组间差异有统计学意义(P<0.05),在梗死区降低趋势更为明显。S1P2 m RNA在术后各组的非梗死区与正常对照心肌之间的表达比较,变化无统计学意义,且各时间点之间无差异,而在梗死区其表达变化较为显著(P<0.01)。S1P3 m RNA在心梗后1周表达显著增强(P<0.01),4周表达出现降低,这种表达抑制在梗死区更为明显(P<0.01和P<0.05)。结论:心室重塑阶段的S1P1、S1P2、S1P3 m RNA表达在非梗死区与梗死区变化不同步且各有特点,这种差异表达可能在心肌梗死后心室重塑过程中有重要意义。
