Introduction:
O-1602 is an agonist for GPR55. GPR55 is a putative endocannabinoid receptor, which also has an affinity for endogenous cannabinoid ligands anandamide and 2-arachidonyl glycerol. These ligands have been shown to induce appetite and reduce energy expenditure which is detrimental to the obese state.
There is limited research looking at the role of O-1602 in vivo. One study has found treatment for 1 week with 0.1mg/kg of O-1602 in Sprague Dawley rats resulted in increased adiposity and reduction of markers involved in lipolysis.
Aim:
To determine the role that O-1602 has on food consumption, body weight, body composition and tissue collagen content in a diet induced obese rat model.
Method:
Sprague Dawley rats were fed a high fat diet (21% fat) for 9 weeks to induce an obese state, and then administered daily ip for 6 weeks with either 5mg/kg of O-1602 or vehicle control. The weight and food intake of the rats were monitored daily, body composition was measured using Echo MRI at baseline (week-9), mid treatment (week-12) and at the end of the treatment period (week-15). Tissues were collected on the last day of the treatment period (week-15). Liver and heart were analysed for collagen content using hydroxy proline assay.
Results/ Conclusion:
Body weight was not altered in animals treated with O-1602, there was however a reduction in body fat (%) by week 15. Food consumption was only decreased in the first week of the six weeks of treatment with O-1602. Organs collected from the animals administered O-1602 visually appeared to have increased surrounding connective tissue, however no difference in collagen content between groups in liver or heart was observed. Further analysis is required to determine the full effects of this compound.
Acknowledgements:
Supported by the Allen Foundation, ACS was supported by Australian Rotary Health Scholarship.