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Nifedipine inhibits activation of transcription factor NF-kappaB
A Matsumori1, Y Nunokawa, S Sasayama
1Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, Japan. amat@kuhp.kyoto-u.ac.jp
Abstract:
This study was performed to examine the effects of the calcium channel blockers, nifedipine, amlodipine, diltiazem, and verapamil on the activation of the transcription factor NF-kappaB. A549 cells, a human epithelium-like lung carcinoma cell line, were transfected with the NF-kappaB reporter plasmid, which contains the luciferase gene driven by promoters containing a TATA element and 5 copies of the kappaB cis-acting element, and co-transfected with 0.2 microg of pSV2neo vector using LipofectAMINE. Nifedipine significantly decreased the expression of luciferase protein stimulated with IL-1beta (1 ng/mL) compared with controls: 80+/-4% at 3 micromol/L, 47+/-2% at 10 micromol/L and 30+/-2% at 30 micromol/L (each, n=3, p<0.0001). The inhibitory effect of nifedipine on promoter activity was concentration-dependent, with a maximal effect obtained at 30 micromol/L. In contrast, high concentrations (30 micromol/L) of amlodipine, diltiazem or verapamil decreased promoter activity to only 89+/-3%, 90+/-3% or 87+/-2% of control, respectively. A comparable inhibitory effect of nifedipine was observed when cells were stimulated with tumor necrosis factor (TNF)-alpha (50 ng/mL), or phorbol 12-myristate 13-acetate (PMA, 100 ng/mL). Electrophoretic mobility shift assay by lipopolysaccharide stimulation, using the RAW 264.7 macrophage cell line, also showed inhibition of NF-kappaB activation by nifedipine in concentrations of 30 and 50 micromol/L. Nifedipine possesses the unique property of inhibiting NF-kappaB, which may be independent of its calcium channel blocking activity, and may, in part, explain its immunosuppressive effect.
Insights
Nifedipine uniquely inhibits the transcription factor NF-kappaB activation, unlike other calcium channel blockers. This finding may explain nifedipine
Area of Science:
- Molecular Biology
- Pharmacology
Background:
- Nuclear Factor kappa B (NF-kappaB) is a key transcription factor involved in immune responses and inflammation.
- Calcium channel blockers (CCBs) are widely used to treat cardiovascular diseases.
Purpose of the Study:
- To investigate the effects of CCBs (nifedipine, amlodipine, diltiazem, verapamil) on NF-kappaB activation.
- To determine if nifedipine possesses unique inhibitory properties against NF-kappaB.
Main Methods:
- A549 human lung carcinoma cells were transfected with an NF-kappaB reporter plasmid.
- Cells were stimulated with Interleukin-1 beta (IL-1beta), Tumor Necrosis Factor-alpha (TNF-alpha), or Phorbol 12-myristate 13-acetate (PMA).
- NF-kappaB activation was assessed by luciferase gene expression and electrophoretic mobility shift assay (EMSA).
Main Results:
- Nifedipine significantly inhibited NF-kappaB activation in a dose-dependent manner.
- Other CCBs (amlodipine, diltiazem, verapamil) showed minimal inhibitory effects at high concentrations.
- Nifedipine inhibited NF-kappaB activation induced by IL-1beta, TNF-alpha, and PMA.
- EMSA confirmed nifedipine's inhibition of NF-kappaB activation in macrophages.
Conclusions:
- Nifedipine exhibits a unique ability to inhibit NF-kappaB activation.
- This inhibitory effect may be independent of its calcium channel blocking activity.
- Nifedipine's NF-kappaB inhibition could contribute to its observed immunosuppressive effects.