Related Experiment Video
Updated: Aug 29, 2026
LDL Cholesterol Uptake Assay Using Live Cell Imaging Analysis with Cell Health Monitoring
Published on: November 17, 2018
Simvastatin suppresses LPS-induced Akt phosphorylation in the human monocyte cell line THP-1
Tushar R Patel1, Siobhan A Corbett
1Department of Surgery, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, New Brunswick, New Jersey 08903, USA.
Background:
Activation of the small GTPase, Rac, requires post-translational modification by isoprenylation. Statins interfere with this process by blocking the synthesis of isoprenoid intermediates. The protein kinase Akt is a multifunctional regulator of cell behavior that has been linked to Rac activation. We have shown that lipopolysaccharide (LPS) stimulation leads to Rac activation in THP-1 cells. Therefore, we hypothesized that LPS stimulation would also activate Akt, a downstream effector of Rac, and that this may be blocked by statin pretreatment.
Materials And Methods:
THP-1 cells were maintained in 1% fetal calf serum with or without 20 microM simvastatin for 24 h, followed by LPS stimulation for increasing time. Cytoskeletal changes were observed using Alexa-Phalloidin. Akt was immunoprecipitated from total cell lysate. Activated Akt was detected by immunoblotting with a phospho-Akt antibody and was quantified by image densitometry.
Results:
LPS stimulation of THP-1 cells results in membrane ruffling and cell polarization. Furthermore, LPS increased Akt activation in THP-1 cells when compared with the nonstimulated controls. Akt phosphorylation peaked after 15 min of LPS stimulation and was suppressed by pretreatment with simvastatin.
Conclusions:
These data demonstrate that LPS stimulation leads to increased Akt phosphorylation, which can be suppressed with simvastatin pretreatment. This suggests one possible mechanism through which simvastatin could modulate LPS-induced signaling events in monocytes to improve the host response to Gram-negative infections.
Insights
Statins inhibit isoprenoid synthesis, crucial for Rac activation. This study shows simvastatin blocks lipopolysaccharide (LPS)-induced Akt activation in THP-1 cells, suggesting a mechanism for statins in modulating immune responses.
Area of Science:
- Cellular signaling
- Immunology
- Pharmacology
Background:
- Rac GTPase activation requires isoprenylation, a process inhibited by statins.
- Akt, a key regulator of cell behavior, is linked to Rac activation.
- Lipopolysaccharide (LPS) stimulates Rac activation in THP-1 cells.
Purpose of the Study:
- To investigate the effect of LPS stimulation on Akt activation in THP-1 cells.
- To determine if statin pretreatment can block LPS-induced Akt activation.
Main Methods:
- THP-1 cells were treated with simvastatin and then stimulated with LPS.
- Cytoskeletal changes were visualized, and Akt activation was assessed via immunoprecipitation and immunoblotting.
- Phospho-Akt levels were quantified using image densitometry.
Main Results:
- LPS stimulation induced membrane ruffling and cell polarization in THP-1 cells.
- LPS significantly increased Akt phosphorylation compared to controls.
- Simvastatin pretreatment suppressed LPS-induced Akt phosphorylation.
Conclusions:
- LPS stimulation activates Akt in THP-1 cells, and this activation is inhibited by simvastatin.
- This finding provides a potential mechanism for statin-mediated modulation of LPS-induced signaling in monocytes.
- Simvastatin may improve host response to Gram-negative infections by affecting these pathways.
Related Concept Videos
01:20Lipid-Lowering Drugs: Statins and Miscellaneous Agents
01:20The JAK-STAT Signaling Pathway
01:38Inflammation