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Updated: Jun 10, 2026
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Absolute Quantitation of Inositol Pyrophosphates by Capillary Electrophoresis Electrospray Ionization Mass Spectrometry
Published on: August 13, 2021
Changes in cellular levels of inositol polyphosphates during apoptosis
Rakhee Agarwal1, Samar Hassen, Nawab Ali
1Graduate Institute of Technology, University of Arkansas at Little Rock, 2801 S. University Ave., Little Rock, AR 72204, USA.
Molecular and Cellular Biochemistry
|August 21, 2010
Summary
Cellular levels of lower inositol phosphates (InsPs) change during apoptosis, with increases in inositol mono- and bis-phosphates and decreases in inositol tris- and tetrakis-phosphates observed. These findings suggest InsPs play a role in apoptosis.
Area of Science:
- Cellular Biology
- Biochemistry
Background:
- Higher inositol polyphosphates are linked to cellular apoptosis.
- The role of lower inositol phosphates (InsPs) in apoptosis is unknown.
- Lower InsPs are involved in cellular signaling, including calcium mobilization.
Purpose of the Study:
- To investigate changes in cellular lower InsP levels during apoptosis.
- To determine if lower InsPs are altered during the process of programmed cell death.
Main Methods:
- Cells were metabolically labeled with [(3)H]myo-inositol.
- Apoptosis was induced using etoposide and sodium fluoride (NaF).
- Changes in InsP levels were quantified using radiolabeling and assessed with and without antimycin A treatment.
Main Results:
- Etoposide and NaF treatments increased inositol mono- and bis-phosphates.
- These treatments decreased inositol tris- and tetrakis-phosphates in a dose- and time-dependent manner.
- Antimycin A partially reversed NaF-induced effects on apoptosis and lower InsP levels.
Conclusions:
- Cellular levels of lower InsPs are significantly altered during apoptosis.
- The observed changes in lower InsPs suggest their involvement in the apoptotic pathway.
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