Limits...
Roscovitine-induced apoptosis in neutrophils and neutrophil progenitors is regulated by the Bcl-2-family members Bim, Puma, Noxa and Mcl-1.

Gautam S, Kirschnek S, Wiesmeier M, Vier J, Häcker G - PLoS ONE (2013)

Bottom Line: The isolated loss of either Bim or noxa provided significant, partial protection while protection through combined loss of Bim and noxa or Bim and Puma was only slightly greater than this individual loss.In progenitor cells there was no protection by the loss of Bim alone but substantial protection by the loss of both Bim and Puma; surprisingly, strongest protection was seen by the isolated loss of noxa.In addition, roscovitine strongly inhibited proliferation in progenitor cells, associated with an accumulation of cells in G2/M-phase.

View Article: PubMed Central - PubMed

Affiliation: Institute for Medical Microbiology and Hygiene, University Medical Center, Freiburg, Freiburg, Germany.

ABSTRACT
Neutrophil granulocyte (neutrophil) apoptosis plays a key role in determining inflammation in infectious and non-infectious settings. Recent work has shown that inhibitors of cyclin-dependent kinases (cdk) such as roscovitine can potently induce neutrophil apoptosis and reduce inflammation. Using a conditional Hoxb8-expression system we tested the participation of Bcl-2-family proteins to roscovitine-induced apoptosis in mouse neutrophils and in neutrophil progenitor cells. Bcl-2 strongly protected against roscovitine-induced apoptosis in neutrophils. The isolated loss of either Bim or noxa provided significant, partial protection while protection through combined loss of Bim and noxa or Bim and Puma was only slightly greater than this individual loss. The only substantial change in protein levels observed was the loss of Mcl-1, which was not transcriptional and was inhibited by proteasome blockade. In progenitor cells there was no protection by the loss of Bim alone but substantial protection by the loss of both Bim and Puma; surprisingly, strongest protection was seen by the isolated loss of noxa. The pattern of protein expression and Mcl-1-regulation in progenitor cells was very similar to the one observed in differentiated neutrophils. In addition, roscovitine strongly inhibited proliferation in progenitor cells, associated with an accumulation of cells in G2/M-phase.

Show MeSH

Related in: MedlinePlus

Roscovitine inhibits proliferation in neutrophil progenitor cells.(A) Left panel gives the numbers of Bcl-2-transgenic progenitor cells in control cultures and in cultures treated with roscovitine for 24 h. Right panel shows the percentages of live cells in these cultures (means/SEM of 3 independent experiments). (B) PI staining (flow cytometry analysis in linear scale) of Bcl-2-transgenic progenitor cells treated with roscovitine for 24 h. Flow cytometry plots are representative of 3 independent experiments.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3815126&req=5

pone-0079352-g007: Roscovitine inhibits proliferation in neutrophil progenitor cells.(A) Left panel gives the numbers of Bcl-2-transgenic progenitor cells in control cultures and in cultures treated with roscovitine for 24 h. Right panel shows the percentages of live cells in these cultures (means/SEM of 3 independent experiments). (B) PI staining (flow cytometry analysis in linear scale) of Bcl-2-transgenic progenitor cells treated with roscovitine for 24 h. Flow cytometry plots are representative of 3 independent experiments.

Mentions: Cyclin-dependent kinases are required for proliferation, and neutrophil progenitors proliferate rapidly. We tested whether the CDK-inhibitor roscovitine inhibited proliferation of neutrophil-progenitors. As shown in Figure 7A, Bcl-2-expressing neutrophil progenitors increased in number over 3-fold during 24 h of culture. Addition of roscovitine completely blocked this increase in population size. This was associated with substantial changes in cell cycle states: in the presence of roscovitine the population in S-phase was strongly reduced, accompanied by an increase in the G2/M-population. In neutrophil progenitors roscovitine thus causes both proliferation arrest and apoptosis, and this may have effects on the supply of mature neutrophils during apoptosis treatment in vivo.


Roscovitine-induced apoptosis in neutrophils and neutrophil progenitors is regulated by the Bcl-2-family members Bim, Puma, Noxa and Mcl-1.

Gautam S, Kirschnek S, Wiesmeier M, Vier J, Häcker G - PLoS ONE (2013)

Roscovitine inhibits proliferation in neutrophil progenitor cells.(A) Left panel gives the numbers of Bcl-2-transgenic progenitor cells in control cultures and in cultures treated with roscovitine for 24 h. Right panel shows the percentages of live cells in these cultures (means/SEM of 3 independent experiments). (B) PI staining (flow cytometry analysis in linear scale) of Bcl-2-transgenic progenitor cells treated with roscovitine for 24 h. Flow cytometry plots are representative of 3 independent experiments.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3815126&req=5

pone-0079352-g007: Roscovitine inhibits proliferation in neutrophil progenitor cells.(A) Left panel gives the numbers of Bcl-2-transgenic progenitor cells in control cultures and in cultures treated with roscovitine for 24 h. Right panel shows the percentages of live cells in these cultures (means/SEM of 3 independent experiments). (B) PI staining (flow cytometry analysis in linear scale) of Bcl-2-transgenic progenitor cells treated with roscovitine for 24 h. Flow cytometry plots are representative of 3 independent experiments.
Mentions: Cyclin-dependent kinases are required for proliferation, and neutrophil progenitors proliferate rapidly. We tested whether the CDK-inhibitor roscovitine inhibited proliferation of neutrophil-progenitors. As shown in Figure 7A, Bcl-2-expressing neutrophil progenitors increased in number over 3-fold during 24 h of culture. Addition of roscovitine completely blocked this increase in population size. This was associated with substantial changes in cell cycle states: in the presence of roscovitine the population in S-phase was strongly reduced, accompanied by an increase in the G2/M-population. In neutrophil progenitors roscovitine thus causes both proliferation arrest and apoptosis, and this may have effects on the supply of mature neutrophils during apoptosis treatment in vivo.

Bottom Line: The isolated loss of either Bim or noxa provided significant, partial protection while protection through combined loss of Bim and noxa or Bim and Puma was only slightly greater than this individual loss.In progenitor cells there was no protection by the loss of Bim alone but substantial protection by the loss of both Bim and Puma; surprisingly, strongest protection was seen by the isolated loss of noxa.In addition, roscovitine strongly inhibited proliferation in progenitor cells, associated with an accumulation of cells in G2/M-phase.

View Article: PubMed Central - PubMed

Affiliation: Institute for Medical Microbiology and Hygiene, University Medical Center, Freiburg, Freiburg, Germany.

ABSTRACT
Neutrophil granulocyte (neutrophil) apoptosis plays a key role in determining inflammation in infectious and non-infectious settings. Recent work has shown that inhibitors of cyclin-dependent kinases (cdk) such as roscovitine can potently induce neutrophil apoptosis and reduce inflammation. Using a conditional Hoxb8-expression system we tested the participation of Bcl-2-family proteins to roscovitine-induced apoptosis in mouse neutrophils and in neutrophil progenitor cells. Bcl-2 strongly protected against roscovitine-induced apoptosis in neutrophils. The isolated loss of either Bim or noxa provided significant, partial protection while protection through combined loss of Bim and noxa or Bim and Puma was only slightly greater than this individual loss. The only substantial change in protein levels observed was the loss of Mcl-1, which was not transcriptional and was inhibited by proteasome blockade. In progenitor cells there was no protection by the loss of Bim alone but substantial protection by the loss of both Bim and Puma; surprisingly, strongest protection was seen by the isolated loss of noxa. The pattern of protein expression and Mcl-1-regulation in progenitor cells was very similar to the one observed in differentiated neutrophils. In addition, roscovitine strongly inhibited proliferation in progenitor cells, associated with an accumulation of cells in G2/M-phase.

Show MeSH
Related in: MedlinePlus