Related Experiment Video
Updated: Aug 10, 2026
Cryosectioning of Contiguous Regions of a Single Mouse Skeletal Muscle for Gene Expression and Histological Analyses
Published on: December 12, 2016
Apoptotic events induced by yessotoxin in myoblast cell lines from rat and mouse
Mónica Suárez Korsnes1, Dyveke Lem Hetland, Arild Espenes
1The Norwegian School of Veterinary Science, P.O. Box 8146 Dep., N-0033 Oslo, Norway. Monica.Suarez@veths.no
Abstract:
This study reports apoptotic events after yessotoxin (YTX) exposure in L6 (rat) and BC3H1 (mouse) skeletal muscle myoblast cell lines. These cell lines are relevant targets to study the cytotoxic effect since this toxin has been reported as cardiotoxic. Mechanisms of action of YTX in multicellular organisms are not fully elucidated. Cell culture studies can contribute to find some of these mechanisms and trace the molecular pathways involved. The present work shows results from exposing cells to 100 nM purified YTX for 72 h. Morphological and biochemical changes characteristic of apoptotic cell death were evaluated in the two cell lines. Immunofluorescence and western blot techniques showed caspase-3 and caspase-9 activation. Western blot analysis of poly(ADP-ribose)-polymerase (PARP) confirmed caspase-3 activation in both cell lines. DNA fragmentation was not detected in these cell lines. This evidence reflect that oligonucleosomal DNA fragmentation is not a biochemical event that can be used as a definitive apoptotic marker in L6 and BC3H1 myoblast cell lines. The results indicate that the time-course and degree of apoptotic events induced by YTX depend on cell line sensitivity.
Insights
Yessotoxin (YTX) triggers apoptosis in rat and mouse muscle cells by activating caspases-3 and 9. DNA fragmentation was not observed, indicating it's not a reliable marker for YTX-induced cell death in these cell lines.
Area of Science:
- Toxicology
- Cell Biology
- Molecular Biology
Background:
- Yessotoxin (YTX) is a marine toxin with known cardiotoxic effects, but its mechanisms of action in skeletal muscle cells are not fully understood.
- Investigating YTX's impact on muscle cells is crucial for understanding its broader toxicological profile.
- Cell culture models provide a controlled environment to elucidate molecular pathways involved in YTX toxicity.
Purpose of the Study:
- To investigate the occurrence and characteristics of apoptotic events in L6 (rat) and BC3H1 (mouse) skeletal muscle myoblast cell lines following YTX exposure.
- To identify the molecular markers and pathways involved in YTX-induced cell death in these myoblast models.
- To evaluate the utility of DNA fragmentation as an apoptotic marker in the context of YTX toxicity in these specific cell lines.
Main Methods:
- Exposure of L6 and BC3H1 myoblast cell lines to 100 nM purified YTX for 72 hours.
- Assessment of morphological and biochemical hallmarks of apoptosis.
- Utilized immunofluorescence and Western blot techniques to detect caspase-3 and caspase-9 activation.
- Western blot analysis of poly(ADP-ribose)-polymerase (PARP) cleavage to confirm caspase-3 activity.
- Evaluated DNA fragmentation as a potential marker of apoptosis.
Main Results:
- YTX exposure induced morphological and biochemical changes consistent with apoptosis in both L6 and BC3H1 cell lines.
- Activation of caspase-3 and caspase-9 was confirmed by immunofluorescence and Western blot.
- Cleavage of PARP, a downstream target of caspase-3, further validated caspase activation.
- Oligonucleosomal DNA fragmentation was not detected in either cell line, suggesting its unreliability as a marker in this context.
- The extent and kinetics of YTX-induced apoptosis varied between the rat and mouse cell lines, highlighting differential sensitivity.
Conclusions:
- YTX induces apoptosis in rat and mouse skeletal muscle myoblasts through caspase-dependent pathways.
- Caspase-3 and caspase-9 activation are key events in YTX-induced myoblast apoptosis.
- Oligonucleosomal DNA fragmentation is not a suitable marker for YTX-induced apoptosis in L6 and BC3H1 myoblast cell lines.
- Cell line sensitivity plays a significant role in the response to YTX exposure, influencing the degree and time-course of apoptotic events.
