(-)-Myrtenol

(-)-Myrtenol accelerates healing of acetic acid-induced gastric ulcers in rats and in human gastric adenocarcinoma cells.[Pubmed:30991046]

Eur J Pharmacol. 2019 Jul 5;854:139-148.

The gastroprotective property of (-)-Myrtenol, a monoterpenoid, has been demonstrated previously against acute gastric ulceration induced by ethanol. However, the healing property of (-)-Myrtenol in a chronic gastric ulcer model remains to be verified. This study evaluated its healing efficacy and the mechanism involved using the rat model of chronic gastric ulcer induced by serosal injection of 80% acetic acid in vivo, and human gastric adenocarcinoma cells (AGS) in vitro. The results showed that compared to vehicle-treated ulcer controls, oral administration of (-)-Myrtenol (50 and 100mg/kg/day) for 7 days promoted ulcer healing, as indicated by significant decreases in ulcer area and volume. The macroscopic and microscopic findings confirmed the healing potential of (-)-Myrtenol. The ulcer healing activity was also associated with significant increases in gastric mucin content, collagen deposition, number of cells with positive marking for proliferating cell nuclear antigen (PCNA), and by changes in the expression of the inflammatory parameters tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and cyclooxygenase (COX)-2, as well as a decrease of metalloproteinases (MMP-9 and MMP-2) activity. Furthermore, in vitro assays using the AGS cultures revealed that (-)-Myrtenol favors wound healing activity via stimulation of cell proliferation and migration without altering the cell viability. Taken together, these findings indicate that (-)-Myrtenol has gastro-cytoprotective and ulcer healing properties that can be further explored to develop a new therapeutic agent from a natural source for the treatment of gastric ulcer.

Anti-inflammatory and anti-remodeling effects of myrtenol in the lungs of asthmatic rats: Histopathological and biochemical findings.[Pubmed:30528469]

Allergol Immunopathol (Madr). 2019 Mar - Apr;47(2):185-193.

INTRODUCTION: Asthma is a chronic inflammatory disease of the airways. In this study, we evaluated the anti-inflammatory effects of myrtenol on the inflammatory indices in the pulmonary parenchyma and airways and on the inflammatory and oxidative indices of the bronchoalveolar lavage fluid (BALF) of asthmatic rats. METHODS: The allergic asthma was induced by sensitization (two weeks) followed by the inhalation of ovalbumin (four weeks). Animals were divided into two main groups: (1) Histopathology, and (2) measurement of inflammatory and oxidative biomarkers in the BALF. Each main group was subdivided into four subgroups: Control, Asthma, Asthma+Dexamethasone and Asthma+Myrtenol. (-)-Myrtenol (50mg/kg) or Dexamethasone (2.5mg/kg) was administered intraperitoneally once a day for one week, at the end of the inhalation period. On day 50, lung histopathologic parameters and inflammatory indices in BALF including INF-gamma, IL-10, IL-1beta, and TNF-alpha and oxidative stress biomarkers (MDA, SOD, and GPX) were measured. RESULT: In the Asthma group, leukocyte infiltration, the thickness of smooth muscle and epithelium of airways wall and the number of goblet cells increased. Myrtenol reduced all of the above-mentioned indices except the epithelium thickness. It also inhibited the increase in BALF IL-1beta, TNF-alpha and MDA and increased the levels of INF-gamma, IL-10 and SOD. CONCLUSION: Our results suggest that myrtenol reduced damage caused by experimental asthma by reducing the inflammatory indices, normalizing the level of interleukins and balancing oxidative stress in the lungs. It also prevented airway remodeling. Myrtenol may be suggested as a potent herbal medicine for the treatment of allergic asthma.