Abstract
Aim: HDL has anti-inflammatory effects on macrophages, although the mechanism of action remains unclear. We hypothesized that HDL suppresses the conversion of macrophage-secreted factors into proinflammatory factors via binding, and tried to identify the factor that could form a complex with HDL and/or apolipoprotein (apo) A-I. Methods and Results: In conditioned media obtained from human monocyte-derived macrophages, we found an apo A-I binding protein and identified the protein as progranulin/proepithelin/acrogranin/PCDGF. Co-immunoprecipitation analysis showing that progranulin binds and forms a complex with apo A-I and the presence of progranulin in the HDL fraction in the sera indicated that progranilin is a novel apolipoprotein. Conditioned media of HEK293 cells transfected with progranulin augmented the expression of TNF-alpha and IL-1-beta on macrophages, but these effects of progranulin were inhibited by co-incubation with HDL or apo A-I. Anti-progranulin antibodies also reduced the expression of TNF-alpha and IL-1-beta on macrophages. Granulins as conversion products derived from progranilin increased TNF-alpha and IL-1-beta expression and the effects were not suppressed by HDL. Conclusions: Our results suggest that the anti-inflammatory effects of HDL on macrophages might be due to suppression of the conversion of progranulin into proinflammatory granulins by forming a complex.
| Original language | English |
|---|---|
| Pages (from-to) | 568-577 |
| Number of pages | 10 |
| Journal | Journal of atherosclerosis and thrombosis |
| Volume | 17 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - 30-06-2010 |
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All Science Journal Classification (ASJC) codes
- Internal Medicine
- Cardiology and Cardiovascular Medicine
- Biochemistry, medical
Cite this
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HDL/apolipoprotein A-I binds to macrophage-derived progranulin and suppresses its conversion into proinflammatory granulins. / Okura, Hanayuki; Yamashita, Shizuya; Ohama, Tohru; Saga, Ayami; Yamamoto-Kakuta, Aya; Hamada, Yoko; Sougawa, Nagako; Ohyama, Reiko; Sawa, Yoshiki; Matsuyama, Akifumi.
In: Journal of atherosclerosis and thrombosis, Vol. 17, No. 6, 30.06.2010, p. 568-577.Research output: Contribution to journal › Article
TY - JOUR
T1 - HDL/apolipoprotein A-I binds to macrophage-derived progranulin and suppresses its conversion into proinflammatory granulins
AU - Okura, Hanayuki
AU - Yamashita, Shizuya
AU - Ohama, Tohru
AU - Saga, Ayami
AU - Yamamoto-Kakuta, Aya
AU - Hamada, Yoko
AU - Sougawa, Nagako
AU - Ohyama, Reiko
AU - Sawa, Yoshiki
AU - Matsuyama, Akifumi
PY - 2010/6/30
Y1 - 2010/6/30
N2 - Aim: HDL has anti-inflammatory effects on macrophages, although the mechanism of action remains unclear. We hypothesized that HDL suppresses the conversion of macrophage-secreted factors into proinflammatory factors via binding, and tried to identify the factor that could form a complex with HDL and/or apolipoprotein (apo) A-I. Methods and Results: In conditioned media obtained from human monocyte-derived macrophages, we found an apo A-I binding protein and identified the protein as progranulin/proepithelin/acrogranin/PCDGF. Co-immunoprecipitation analysis showing that progranulin binds and forms a complex with apo A-I and the presence of progranulin in the HDL fraction in the sera indicated that progranilin is a novel apolipoprotein. Conditioned media of HEK293 cells transfected with progranulin augmented the expression of TNF-alpha and IL-1-beta on macrophages, but these effects of progranulin were inhibited by co-incubation with HDL or apo A-I. Anti-progranulin antibodies also reduced the expression of TNF-alpha and IL-1-beta on macrophages. Granulins as conversion products derived from progranilin increased TNF-alpha and IL-1-beta expression and the effects were not suppressed by HDL. Conclusions: Our results suggest that the anti-inflammatory effects of HDL on macrophages might be due to suppression of the conversion of progranulin into proinflammatory granulins by forming a complex.
AB - Aim: HDL has anti-inflammatory effects on macrophages, although the mechanism of action remains unclear. We hypothesized that HDL suppresses the conversion of macrophage-secreted factors into proinflammatory factors via binding, and tried to identify the factor that could form a complex with HDL and/or apolipoprotein (apo) A-I. Methods and Results: In conditioned media obtained from human monocyte-derived macrophages, we found an apo A-I binding protein and identified the protein as progranulin/proepithelin/acrogranin/PCDGF. Co-immunoprecipitation analysis showing that progranulin binds and forms a complex with apo A-I and the presence of progranulin in the HDL fraction in the sera indicated that progranilin is a novel apolipoprotein. Conditioned media of HEK293 cells transfected with progranulin augmented the expression of TNF-alpha and IL-1-beta on macrophages, but these effects of progranulin were inhibited by co-incubation with HDL or apo A-I. Anti-progranulin antibodies also reduced the expression of TNF-alpha and IL-1-beta on macrophages. Granulins as conversion products derived from progranilin increased TNF-alpha and IL-1-beta expression and the effects were not suppressed by HDL. Conclusions: Our results suggest that the anti-inflammatory effects of HDL on macrophages might be due to suppression of the conversion of progranulin into proinflammatory granulins by forming a complex.
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U2 - 10.5551/jat.3921
DO - 10.5551/jat.3921
M3 - Article
C2 - 20215705
AN - SCOPUS:77954717645
VL - 17
SP - 568
EP - 577
JO - Journal of Atherosclerosis and Thrombosis
JF - Journal of Atherosclerosis and Thrombosis
SN - 1340-3478
IS - 6
ER -