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Role of astroglia in Down's syndrome revealed by patient-derived human-induced pluripotent stem cells.

Chen C, Jiang P, Xue H, Peterson SE, Tran HT, McCann AE, Parast MM, Li S, Pleasure DE, Laurent LC, Loring JF, Liu Y, Deng W - Nat Commun (2014)

Bottom Line: DS astroglia exhibit higher levels of reactive oxygen species and lower levels of synaptogenic molecules.Transplantation studies show that DS astroglia do not promote neurogenesis of endogenous neural stem cells in vivo.Finally, we show that the FDA-approved antibiotic drug, minocycline, partially corrects the pathological phenotypes of DS astroglia by specifically modulating the expression of S100B, GFAP, inducible nitric oxide synthase, and thrombospondins 1 and 2 in DS astroglia.

View Article: PubMed Central - PubMed

Affiliation: 1] Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, California 95817, USA [2] Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children, Sacramento, California 95817, USA [3] Department of Neurology, Institute of Neurology, Tianjin General Hospital, Tianjin Medical University, Tianjin 300070, China [4].

ABSTRACT
Down's syndrome (DS), caused by trisomy of human chromosome 21, is the most common genetic cause of intellectual disability. Here we use induced pluripotent stem cells (iPSCs) derived from DS patients to identify a role for astrocytes in DS pathogenesis. DS astroglia exhibit higher levels of reactive oxygen species and lower levels of synaptogenic molecules. Astrocyte-conditioned medium collected from DS astroglia causes toxicity to neurons, and fails to promote neuronal ion channel maturation and synapse formation. Transplantation studies show that DS astroglia do not promote neurogenesis of endogenous neural stem cells in vivo. We also observed abnormal gene expression profiles from DS astroglia. Finally, we show that the FDA-approved antibiotic drug, minocycline, partially corrects the pathological phenotypes of DS astroglia by specifically modulating the expression of S100B, GFAP, inducible nitric oxide synthase, and thrombospondins 1 and 2 in DS astroglia. Our studies shed light on the pathogenesis and possible treatment of DS by targeting astrocytes with a clinically available drug.

No MeSH data available.


Related in: MedlinePlus

The effects of DS astroglia on the maturation of voltage-gated ionchannels.(a) Representative tracings showing that the inward sodium currents(INa) were recorded from a DS neuron (left panel). TheINa can be blocked by 1 μMTTX (middle panel).The tracing of right panel was obtained by digitally subtracting the middlepanel from the left panel to show the INa component. TheINa was elicited by a series of depolarizing voltagesteps (inset, from −70 to −50 mV) after aprepulse to −100 mV for 100 ms. Similarresults were observed from 10 other cells. (b) Representativetracings showing potassium currents (IK) recorded from aDS neuron in the presence of TTX. Left panel, the overall IKrecorded with voltage clamp at voltages from −70 to−50 mV (inset, 200 ms duration,20 mV increments) preceded by a prepulse conditioning potentialof −80 mV, 300 ms. With a prepulse to−80 mV, the overall IK includesIKA and sustained outward current IKD.Middle panel, IKD recorded with voltage clamp at voltagesfrom −70 to −50 mV (inset,200 ms duration, 20 mV increments) preceded by aprepulse conditioning potential of +20 mV, 300 ms. Theprepulse to +20 mV inactivates IKA component.Right panel, the IKA component obtained by digitallysubtracting the IKD, middle panel from theIK, left panel. (c–e) TheI–V relationship of INa,IKD and IKA recorded from DS neuronsand control (Cont) neurons. Pooled data, n=10 for each group.(f) Representative tracings showing the INa,IKD and IKA recorded from Contneurons cultured with DS ACM and Cont ACM, and DS neurons cultured with DSACM, Cont ACM and DS-MinoACM. (g–i) I–Vrelationship of INa, IKD andIKA recorded from DS and Cont neurons fed withdifferent ACM. The current densities of INa,IKD and IKA recorded from neuronsfed with DS ACM were smaller than those recorded from neurons fed with ContACM and DS-Mino ACM;one-way analysis of variance test, *P<0.05, comparison betweenCont Neu+DS ACM group with other groups fed with Cont ACM andDS-Mino ACM.#P<0.05 comparison between DS Neu+DS ACMgroup with other groups fed with Cont ACM and DS-Mino ACM. n=10 for eachgroup. Data are presented as mean±s.e.m.
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f5: The effects of DS astroglia on the maturation of voltage-gated ionchannels.(a) Representative tracings showing that the inward sodium currents(INa) were recorded from a DS neuron (left panel). TheINa can be blocked by 1 μMTTX (middle panel).The tracing of right panel was obtained by digitally subtracting the middlepanel from the left panel to show the INa component. TheINa was elicited by a series of depolarizing voltagesteps (inset, from −70 to −50 mV) after aprepulse to −100 mV for 100 ms. Similarresults were observed from 10 other cells. (b) Representativetracings showing potassium currents (IK) recorded from aDS neuron in the presence of TTX. Left panel, the overall IKrecorded with voltage clamp at voltages from −70 to−50 mV (inset, 200 ms duration,20 mV increments) preceded by a prepulse conditioning potentialof −80 mV, 300 ms. With a prepulse to−80 mV, the overall IK includesIKA and sustained outward current IKD.Middle panel, IKD recorded with voltage clamp at voltagesfrom −70 to −50 mV (inset,200 ms duration, 20 mV increments) preceded by aprepulse conditioning potential of +20 mV, 300 ms. Theprepulse to +20 mV inactivates IKA component.Right panel, the IKA component obtained by digitallysubtracting the IKD, middle panel from theIK, left panel. (c–e) TheI–V relationship of INa,IKD and IKA recorded from DS neuronsand control (Cont) neurons. Pooled data, n=10 for each group.(f) Representative tracings showing the INa,IKD and IKA recorded from Contneurons cultured with DS ACM and Cont ACM, and DS neurons cultured with DSACM, Cont ACM and DS-MinoACM. (g–i) I–Vrelationship of INa, IKD andIKA recorded from DS and Cont neurons fed withdifferent ACM. The current densities of INa,IKD and IKA recorded from neuronsfed with DS ACM were smaller than those recorded from neurons fed with ContACM and DS-Mino ACM;one-way analysis of variance test, *P<0.05, comparison betweenCont Neu+DS ACM group with other groups fed with Cont ACM andDS-Mino ACM.#P<0.05 comparison between DS Neu+DS ACMgroup with other groups fed with Cont ACM and DS-Mino ACM. n=10 for eachgroup. Data are presented as mean±s.e.m.

Mentions: The development of the aforementioned electrophysiological properties is largelydependent on the maturation of voltage-gated ionic currents1537. To explore whether DS neurons express functional voltage-gated ioniccurrents similar to control neurons, we next recorded the voltage-gated sodiumcurrent (INa) and potassium current (IK)from 6- to 7-week-old control and DS neurons. As shown in Fig.5a left panel, the whole-cell voltage-gated ionic currents from a DSneuron were induced by voltage steps from a holding potential of−60 mV. The rapidly inactivated inwardINa was completely blocked by 1 μMtetrodotoxin(TTX; Fig.5a middle panel). The INa was revealed by digitallysubtracting the currents recorded in the presence of TTX from the currents recorded in theabsence of TTX (Fig. 5a, right panel). To examine the outwardIK, we then recorded the whole-cell voltage-gated ioniccurrents in the presence of 1 μM TTX with a prepulse to−80 mV (Fig. 5b, left panel).Previous studies3739 showed that two distinctIK current components, transient component of inactivatingA-type potassium current (IKA) and sustained component ofdelayed rectifier potassium current (IKD) were recorded fromhESC-derived neurons, and that the two components of IK couldbe separated by different prepulse stimulation40. We alsoobserved these two components of IK in DS neurons (Fig. 5b, middle and right panels). As shown in Supplementary Fig. 7, theIKA component was highly sensitive to potassium channelblocker 4-aminopyridine,thereby leaving the sustained IKD currents. TheIKD component was then further inhibited by potassiumchannel blocker tetraethylammoniumchloride. The current–voltage(I–V) relationship for INa,IKD and IKA of DS neurons and controlneurons were shown in Fig. 5c–e, respectively.The current density of INa, IKD andIKA were not significantly different between DS neuronsand control neurons (n=10 for each group, P>0.05),suggesting the normal intrinsic maturation of INa andIK of DS neurons. To examine whether the voltage-gated ionchannels in DS neurons could be modulated by DS astroglia, we further recordedthe currents from 6- to 7-week-old DS and control neurons fed with DS ACM,control ACM or DS-Mino ACMstarting at 4-week-old. Interestingly, as shown in Fig.5f, INa, IKD andIKA recorded from DS and control neurons fed with controlACM and DS-Mino ACM hadsignificantly larger current density than those recorded from neurons fed withDS ACM (n=10 for each group; P<0.05). TheI–V curves for INa,IKD and IKA were shown in Fig. 5g–i, respectively. Taken together, these resultsdemonstrate that DS neurons possess intrinsic INa andIK similar to control neurons, and exhibit similar passiveand active electrophysiological properties to control neurons, and that DSastroglia fail to promote the cellular maturation and synapse formation of theiPSC-derived neurons.


Role of astroglia in Down's syndrome revealed by patient-derived human-induced pluripotent stem cells.

Chen C, Jiang P, Xue H, Peterson SE, Tran HT, McCann AE, Parast MM, Li S, Pleasure DE, Laurent LC, Loring JF, Liu Y, Deng W - Nat Commun (2014)

The effects of DS astroglia on the maturation of voltage-gated ionchannels.(a) Representative tracings showing that the inward sodium currents(INa) were recorded from a DS neuron (left panel). TheINa can be blocked by 1 μMTTX (middle panel).The tracing of right panel was obtained by digitally subtracting the middlepanel from the left panel to show the INa component. TheINa was elicited by a series of depolarizing voltagesteps (inset, from −70 to −50 mV) after aprepulse to −100 mV for 100 ms. Similarresults were observed from 10 other cells. (b) Representativetracings showing potassium currents (IK) recorded from aDS neuron in the presence of TTX. Left panel, the overall IKrecorded with voltage clamp at voltages from −70 to−50 mV (inset, 200 ms duration,20 mV increments) preceded by a prepulse conditioning potentialof −80 mV, 300 ms. With a prepulse to−80 mV, the overall IK includesIKA and sustained outward current IKD.Middle panel, IKD recorded with voltage clamp at voltagesfrom −70 to −50 mV (inset,200 ms duration, 20 mV increments) preceded by aprepulse conditioning potential of +20 mV, 300 ms. Theprepulse to +20 mV inactivates IKA component.Right panel, the IKA component obtained by digitallysubtracting the IKD, middle panel from theIK, left panel. (c–e) TheI–V relationship of INa,IKD and IKA recorded from DS neuronsand control (Cont) neurons. Pooled data, n=10 for each group.(f) Representative tracings showing the INa,IKD and IKA recorded from Contneurons cultured with DS ACM and Cont ACM, and DS neurons cultured with DSACM, Cont ACM and DS-MinoACM. (g–i) I–Vrelationship of INa, IKD andIKA recorded from DS and Cont neurons fed withdifferent ACM. The current densities of INa,IKD and IKA recorded from neuronsfed with DS ACM were smaller than those recorded from neurons fed with ContACM and DS-Mino ACM;one-way analysis of variance test, *P<0.05, comparison betweenCont Neu+DS ACM group with other groups fed with Cont ACM andDS-Mino ACM.#P<0.05 comparison between DS Neu+DS ACMgroup with other groups fed with Cont ACM and DS-Mino ACM. n=10 for eachgroup. Data are presented as mean±s.e.m.
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f5: The effects of DS astroglia on the maturation of voltage-gated ionchannels.(a) Representative tracings showing that the inward sodium currents(INa) were recorded from a DS neuron (left panel). TheINa can be blocked by 1 μMTTX (middle panel).The tracing of right panel was obtained by digitally subtracting the middlepanel from the left panel to show the INa component. TheINa was elicited by a series of depolarizing voltagesteps (inset, from −70 to −50 mV) after aprepulse to −100 mV for 100 ms. Similarresults were observed from 10 other cells. (b) Representativetracings showing potassium currents (IK) recorded from aDS neuron in the presence of TTX. Left panel, the overall IKrecorded with voltage clamp at voltages from −70 to−50 mV (inset, 200 ms duration,20 mV increments) preceded by a prepulse conditioning potentialof −80 mV, 300 ms. With a prepulse to−80 mV, the overall IK includesIKA and sustained outward current IKD.Middle panel, IKD recorded with voltage clamp at voltagesfrom −70 to −50 mV (inset,200 ms duration, 20 mV increments) preceded by aprepulse conditioning potential of +20 mV, 300 ms. Theprepulse to +20 mV inactivates IKA component.Right panel, the IKA component obtained by digitallysubtracting the IKD, middle panel from theIK, left panel. (c–e) TheI–V relationship of INa,IKD and IKA recorded from DS neuronsand control (Cont) neurons. Pooled data, n=10 for each group.(f) Representative tracings showing the INa,IKD and IKA recorded from Contneurons cultured with DS ACM and Cont ACM, and DS neurons cultured with DSACM, Cont ACM and DS-MinoACM. (g–i) I–Vrelationship of INa, IKD andIKA recorded from DS and Cont neurons fed withdifferent ACM. The current densities of INa,IKD and IKA recorded from neuronsfed with DS ACM were smaller than those recorded from neurons fed with ContACM and DS-Mino ACM;one-way analysis of variance test, *P<0.05, comparison betweenCont Neu+DS ACM group with other groups fed with Cont ACM andDS-Mino ACM.#P<0.05 comparison between DS Neu+DS ACMgroup with other groups fed with Cont ACM and DS-Mino ACM. n=10 for eachgroup. Data are presented as mean±s.e.m.
Mentions: The development of the aforementioned electrophysiological properties is largelydependent on the maturation of voltage-gated ionic currents1537. To explore whether DS neurons express functional voltage-gated ioniccurrents similar to control neurons, we next recorded the voltage-gated sodiumcurrent (INa) and potassium current (IK)from 6- to 7-week-old control and DS neurons. As shown in Fig.5a left panel, the whole-cell voltage-gated ionic currents from a DSneuron were induced by voltage steps from a holding potential of−60 mV. The rapidly inactivated inwardINa was completely blocked by 1 μMtetrodotoxin(TTX; Fig.5a middle panel). The INa was revealed by digitallysubtracting the currents recorded in the presence of TTX from the currents recorded in theabsence of TTX (Fig. 5a, right panel). To examine the outwardIK, we then recorded the whole-cell voltage-gated ioniccurrents in the presence of 1 μM TTX with a prepulse to−80 mV (Fig. 5b, left panel).Previous studies3739 showed that two distinctIK current components, transient component of inactivatingA-type potassium current (IKA) and sustained component ofdelayed rectifier potassium current (IKD) were recorded fromhESC-derived neurons, and that the two components of IK couldbe separated by different prepulse stimulation40. We alsoobserved these two components of IK in DS neurons (Fig. 5b, middle and right panels). As shown in Supplementary Fig. 7, theIKA component was highly sensitive to potassium channelblocker 4-aminopyridine,thereby leaving the sustained IKD currents. TheIKD component was then further inhibited by potassiumchannel blocker tetraethylammoniumchloride. The current–voltage(I–V) relationship for INa,IKD and IKA of DS neurons and controlneurons were shown in Fig. 5c–e, respectively.The current density of INa, IKD andIKA were not significantly different between DS neuronsand control neurons (n=10 for each group, P>0.05),suggesting the normal intrinsic maturation of INa andIK of DS neurons. To examine whether the voltage-gated ionchannels in DS neurons could be modulated by DS astroglia, we further recordedthe currents from 6- to 7-week-old DS and control neurons fed with DS ACM,control ACM or DS-Mino ACMstarting at 4-week-old. Interestingly, as shown in Fig.5f, INa, IKD andIKA recorded from DS and control neurons fed with controlACM and DS-Mino ACM hadsignificantly larger current density than those recorded from neurons fed withDS ACM (n=10 for each group; P<0.05). TheI–V curves for INa,IKD and IKA were shown in Fig. 5g–i, respectively. Taken together, these resultsdemonstrate that DS neurons possess intrinsic INa andIK similar to control neurons, and exhibit similar passiveand active electrophysiological properties to control neurons, and that DSastroglia fail to promote the cellular maturation and synapse formation of theiPSC-derived neurons.

Bottom Line: DS astroglia exhibit higher levels of reactive oxygen species and lower levels of synaptogenic molecules.Transplantation studies show that DS astroglia do not promote neurogenesis of endogenous neural stem cells in vivo.Finally, we show that the FDA-approved antibiotic drug, minocycline, partially corrects the pathological phenotypes of DS astroglia by specifically modulating the expression of S100B, GFAP, inducible nitric oxide synthase, and thrombospondins 1 and 2 in DS astroglia.

View Article: PubMed Central - PubMed

Affiliation: 1] Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, California 95817, USA [2] Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children, Sacramento, California 95817, USA [3] Department of Neurology, Institute of Neurology, Tianjin General Hospital, Tianjin Medical University, Tianjin 300070, China [4].

ABSTRACT
Down's syndrome (DS), caused by trisomy of human chromosome 21, is the most common genetic cause of intellectual disability. Here we use induced pluripotent stem cells (iPSCs) derived from DS patients to identify a role for astrocytes in DS pathogenesis. DS astroglia exhibit higher levels of reactive oxygen species and lower levels of synaptogenic molecules. Astrocyte-conditioned medium collected from DS astroglia causes toxicity to neurons, and fails to promote neuronal ion channel maturation and synapse formation. Transplantation studies show that DS astroglia do not promote neurogenesis of endogenous neural stem cells in vivo. We also observed abnormal gene expression profiles from DS astroglia. Finally, we show that the FDA-approved antibiotic drug, minocycline, partially corrects the pathological phenotypes of DS astroglia by specifically modulating the expression of S100B, GFAP, inducible nitric oxide synthase, and thrombospondins 1 and 2 in DS astroglia. Our studies shed light on the pathogenesis and possible treatment of DS by targeting astrocytes with a clinically available drug.

No MeSH data available.


Related in: MedlinePlus