Limits...
Release of Phosphorylated HSP27 (HSPB1) from Platelets Is Accompanied with the Acceleration of Aggregation in Diabetic Patients.

Tokuda H, Kuroyanagi G, Tsujimoto M, Enomoto Y, Matsushima-Nishiwaki R, Onuma T, Kojima A, Doi T, Tanabe K, Akamatsu S, Iida H, Ogura S, Otsuka T, Iwama T, Tanikawa T, Ishikawa K, Kojima K, Kozawa O - PLoS ONE (2015)

Bottom Line: Area under the curve (AUC) of small aggregation (9-25 μm) induced by 0.3 μg/ml collagen was inversely proportional to the levels of released HSP27.AUC of large aggregation (50-70 μm) was directly proportional to the levels of released HSP27.Exogenous recombinant phosphorylated- HSP27 hardly affected the aggregation or the released levels of PDGF-AB induced by collagen.

View Article: PubMed Central - PubMed

Affiliation: Department of Clinical Laboratory, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan; Department of Pharmacology, Gifu University Graduate School of Medicine, Gifu, Japan.

ABSTRACT
We investigated the relationship between HSP27 phosphorylation and collagen-stimulated activation of platelets in patients with diabetes mellitus (DM). Platelet-rich plasma was prepared from blood of type 2 DM patients. The platelet aggregation was analyzed in size of aggregates by an aggregometer using a laser scattering method. The protein phosphorylation was analyzed by Western blotting. Phosphorylated-HSP27 and PDGF-AB released from platelets were measured by ELISA. The phosphorylated-HSP27 levels at Ser-78 and Ser-82 induced by collagen were directly proportional to the platelet aggregation. Total HSP27 levels in platelets were decreased concomitantly with the phosphorylation. The released HSP27 levels were significantly correlated with the phosphorylated levels of HSP27 in the platelets stimulated by 0.3 μg/ml collagen. The low dose collagen-stimulated release of HSP27 was detected but relatively small in healthy donors. The released levels of PDGF-AB were in parallel with the levels of released HSP27. Area under the curve (AUC) of small aggregation (9-25 μm) induced by 0.3 μg/ml collagen was inversely proportional to the levels of released HSP27. AUC of large aggregation (50-70 μm) was directly proportional to the levels of released HSP27. Exogenous recombinant phosphorylated- HSP27 hardly affected the aggregation or the released levels of PDGF-AB induced by collagen. These results strongly suggest that HSP27 is released from human platelets accompanied with its phosphorylation induced by collagen, which is correlated with the acceleration of platelet aggregation in type 2 DM patients.

No MeSH data available.


Related in: MedlinePlus

The relationship between individual levels of released phosphorylated-HSP27 and the levels of PDGF-AB induced by collagen in type 2 DM patients.The level of phosphorylated-HSP27 and PDGF-AB in the supernatant of the conditioned mixture after platelet aggregation stimulated by 0.3 μg of collagen for 30 min was determined using specific ELISA kits. The baseline levels in unstimulated samples were subtracted from each of the individual released phosphorylated-HSP27 levels and the PDGF-AB levels. Each data were collected with the platelet counts, and were plotted and analyzed by linear regression analysis. (a) Whole subjects (n = 35) were plotted. (b) The residual subjects after excluding what concentration of phosphorylated-HSP27 could not be detected (n = 30) were plotted.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4457785&req=5

pone.0128977.g004: The relationship between individual levels of released phosphorylated-HSP27 and the levels of PDGF-AB induced by collagen in type 2 DM patients.The level of phosphorylated-HSP27 and PDGF-AB in the supernatant of the conditioned mixture after platelet aggregation stimulated by 0.3 μg of collagen for 30 min was determined using specific ELISA kits. The baseline levels in unstimulated samples were subtracted from each of the individual released phosphorylated-HSP27 levels and the PDGF-AB levels. Each data were collected with the platelet counts, and were plotted and analyzed by linear regression analysis. (a) Whole subjects (n = 35) were plotted. (b) The residual subjects after excluding what concentration of phosphorylated-HSP27 could not be detected (n = 30) were plotted.

Mentions: PDGF-AB is recognized as a mitogenic mediator which is secreted from activated platelets and promotes the progress of atherosclerosis [1]. We have reported that collagen-induced HSP27 phosphorylation is sufficient for PDGF-AB secretion from human platelets and that the secretion is regulated by Rac [19]. Thus, we compared the collagen-induced PDGF-AB secretion against the individual levels of released phosphorylated-HSP27 from the platelets of type 2 DM patients. The levels of PDGF-AB secretion induced by 0.3 μg/ml collagen was significantly correlated with the levels of released phosphorylated-HSP27 (R2 = 0.414, p<0.001, n = 35) (Fig 4A). The relationship between the levels of PDGF-AB secretion and the levels of released phosphorylated-HSP27 was slightly weaken by the exclusion of non-responding samples, but was significant (R2 = 0.337, p = 0.001, n = 30) (Fig 4B).


Release of Phosphorylated HSP27 (HSPB1) from Platelets Is Accompanied with the Acceleration of Aggregation in Diabetic Patients.

Tokuda H, Kuroyanagi G, Tsujimoto M, Enomoto Y, Matsushima-Nishiwaki R, Onuma T, Kojima A, Doi T, Tanabe K, Akamatsu S, Iida H, Ogura S, Otsuka T, Iwama T, Tanikawa T, Ishikawa K, Kojima K, Kozawa O - PLoS ONE (2015)

The relationship between individual levels of released phosphorylated-HSP27 and the levels of PDGF-AB induced by collagen in type 2 DM patients.The level of phosphorylated-HSP27 and PDGF-AB in the supernatant of the conditioned mixture after platelet aggregation stimulated by 0.3 μg of collagen for 30 min was determined using specific ELISA kits. The baseline levels in unstimulated samples were subtracted from each of the individual released phosphorylated-HSP27 levels and the PDGF-AB levels. Each data were collected with the platelet counts, and were plotted and analyzed by linear regression analysis. (a) Whole subjects (n = 35) were plotted. (b) The residual subjects after excluding what concentration of phosphorylated-HSP27 could not be detected (n = 30) were plotted.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4457785&req=5

pone.0128977.g004: The relationship between individual levels of released phosphorylated-HSP27 and the levels of PDGF-AB induced by collagen in type 2 DM patients.The level of phosphorylated-HSP27 and PDGF-AB in the supernatant of the conditioned mixture after platelet aggregation stimulated by 0.3 μg of collagen for 30 min was determined using specific ELISA kits. The baseline levels in unstimulated samples were subtracted from each of the individual released phosphorylated-HSP27 levels and the PDGF-AB levels. Each data were collected with the platelet counts, and were plotted and analyzed by linear regression analysis. (a) Whole subjects (n = 35) were plotted. (b) The residual subjects after excluding what concentration of phosphorylated-HSP27 could not be detected (n = 30) were plotted.
Mentions: PDGF-AB is recognized as a mitogenic mediator which is secreted from activated platelets and promotes the progress of atherosclerosis [1]. We have reported that collagen-induced HSP27 phosphorylation is sufficient for PDGF-AB secretion from human platelets and that the secretion is regulated by Rac [19]. Thus, we compared the collagen-induced PDGF-AB secretion against the individual levels of released phosphorylated-HSP27 from the platelets of type 2 DM patients. The levels of PDGF-AB secretion induced by 0.3 μg/ml collagen was significantly correlated with the levels of released phosphorylated-HSP27 (R2 = 0.414, p<0.001, n = 35) (Fig 4A). The relationship between the levels of PDGF-AB secretion and the levels of released phosphorylated-HSP27 was slightly weaken by the exclusion of non-responding samples, but was significant (R2 = 0.337, p = 0.001, n = 30) (Fig 4B).

Bottom Line: Area under the curve (AUC) of small aggregation (9-25 μm) induced by 0.3 μg/ml collagen was inversely proportional to the levels of released HSP27.AUC of large aggregation (50-70 μm) was directly proportional to the levels of released HSP27.Exogenous recombinant phosphorylated- HSP27 hardly affected the aggregation or the released levels of PDGF-AB induced by collagen.

View Article: PubMed Central - PubMed

Affiliation: Department of Clinical Laboratory, National Center for Geriatrics and Gerontology, Obu, Aichi, Japan; Department of Pharmacology, Gifu University Graduate School of Medicine, Gifu, Japan.

ABSTRACT
We investigated the relationship between HSP27 phosphorylation and collagen-stimulated activation of platelets in patients with diabetes mellitus (DM). Platelet-rich plasma was prepared from blood of type 2 DM patients. The platelet aggregation was analyzed in size of aggregates by an aggregometer using a laser scattering method. The protein phosphorylation was analyzed by Western blotting. Phosphorylated-HSP27 and PDGF-AB released from platelets were measured by ELISA. The phosphorylated-HSP27 levels at Ser-78 and Ser-82 induced by collagen were directly proportional to the platelet aggregation. Total HSP27 levels in platelets were decreased concomitantly with the phosphorylation. The released HSP27 levels were significantly correlated with the phosphorylated levels of HSP27 in the platelets stimulated by 0.3 μg/ml collagen. The low dose collagen-stimulated release of HSP27 was detected but relatively small in healthy donors. The released levels of PDGF-AB were in parallel with the levels of released HSP27. Area under the curve (AUC) of small aggregation (9-25 μm) induced by 0.3 μg/ml collagen was inversely proportional to the levels of released HSP27. AUC of large aggregation (50-70 μm) was directly proportional to the levels of released HSP27. Exogenous recombinant phosphorylated- HSP27 hardly affected the aggregation or the released levels of PDGF-AB induced by collagen. These results strongly suggest that HSP27 is released from human platelets accompanied with its phosphorylation induced by collagen, which is correlated with the acceleration of platelet aggregation in type 2 DM patients.

No MeSH data available.


Related in: MedlinePlus