Introduction:
1,8-cineole belongs to the bicyclic epoxy monoterpenes, more precisely the lime oxides.
The organic compound is present as a colorless liquid. It is used in respiratory diseases
such as bronchitis, chronic, acute sinusitis but also asthma and hay fever. In addition
to the WNT/beta-catenin signaling pathway and its central regulator protein GSK3alpha/beta,
TNF-alpha and TGF-beta were the focus of the investigations.
Methods:
To investigate the molecular influence of 1,8-cineole on inflammation-relevant signaling
cascades in Polypsis nasi and HNSCC, extensive studies were performed at the RNA and
protein level using PCR, microarray analysis, Western hybridization and immunohistochemistry.
Results:
The inhibitory effect of cineole on the activity of the WNT/ß-catenin signaling pathway,
and thus ultimately on the progression of HNSCC and polyposis nasi, was demonstrated
by a broad spectrum of cell and molecular biological analyzes. In addition, we were
able to show that 1,8-cineol leads to a massive up-regulation of the TNF-alpha (tumor
necrosis factor-alpha) signal transduction pathway and to a marked upregulation of
the TGFß (transforming growth factor) receptor. The TNF-alpha and TGF-beta signal
transduction pathways have manifold functions and can stimulate cell death (apoptosis),
cell proliferation, cell differentiation and secretion of various cytokines.
Conclusion:
The results obtained show a significant influence of 1,8-cineole on the molecular
regulation of different inflammation-relevant biosynthetic pathways and thus open
up numerous starting points for innovative therapeutic approaches.
