Marihuana continues to be a controversial topic in todays society. The plant material is used recreationally as a stupefacient and has a purported medicinal use. In fact, anecdotal information about its medicinal properties has been such that Health Canada has recently started an initiative to provide a well characterized supply of plant tissue to researchers interested in examining its potential medicinal properties. Simultaneously this same material is being provided for those subjects who are licensed to use marihuana as a medicine. <p>In order to further study marihuana and its component cannabinoids it is essential to be able to discern both the cannabinoid content in the product being supplied and more importantly the cannabinoid profile in the delivery system. At present the most common route of administration is via inhalation of the combusted plant material. Consequently methods capable of measuring the cannabinoid content in combusted plant material would be very useful in order to make meaningful study of the pharmacokinetics of the cannabinoids delivered by this route. <p>Investigations were carried out to develop a method and study the volatile constituents of combusted marihuana plant material in a semi-enclosed environment. Thus the hypothesis of this research is that qualitative and quantitative information can be obtained from the combustion products of cannabis plant tissue. The method relies upon the solid phase extraction of smoke arising from the combustion of plant material in a variety of combustion chambers. The combustion chambers were designed to reflect the current marihuana paraphernalia in use as well as a high efficiency in vitro system. Both the qualitative and quantitative levels of a limited number of cannabinoids were evaluated before and after combustion. A quantitative Liquid Chromatography Ultra Violet (LC-UV) detector method was validated for the analysis of a selected group of cannabinoids ( Δ9-tetrahydrocannabinol (THC), cannabinol (CBN), cannabidiol (CBD) and tetrahydrocannabinolic acid (THCA) . When this method was applied to plant material available through the medical marijuana initiative the following observations were made on the combustion products:<p> <table style="text-align: left; width: 397px;" border="1" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="width: 119px;">Material</td> <td style="width: 59px;">CBD</td> <td style="width: 59px;">CBN</td> <td style="width: 59px;">THC</td> <td style="width: 59px;">THCA</td> </tr> <tr> <td style="width: 119px;">Analyzed</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> </tr> <tr> <td style="width: 119px;">Plant</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">890</td> </tr> <tr> <td style="width: 119px;">Combusted</td> <td style="width: 59px;">20</td> <td style="width: 59px;">14</td> <td style="width: 59px;">420</td> <td style="width: 59px;">28</td> </tr> </tbody> </table> 5 mg plant tissue extracted using a validated HPLC-UV method <p> 5 mg plant tissue combusted in a closed combustion chamber.<p> BLQ: below level of quantification (<12.5 ug/mL)<p>These results sparked further research into the quantitative transformation of cannabinoids during the combustion process. In this regard, it was shown that THC, CBD and CBN all could be recovered at approximately a 90% ratio upon combustion However, THCA was thermally converted such that very little remains after combustion and furthermore, its degradation product, THC can only account for 50% of the THCA. The latter observation is important since there has been a prevailing thought that THCA is quantitatively transformed during combustion to THC while in fact this transformation is approximately 50%. This finding must be considered when pharmacokinetic studies are carried out using inhalation of combusted plant material as the delivery system.<p>A further finding of this research is that not all popular combustion devices yield identical quantitative cannabinoid profiles. In this regard, the simpler pipe systems result in the highest yields of heat transformed cannabinoids while the vaporizer systems have the lowest cannabinoid yields.

Marihuana continues to be a controversial topic in todays society. The plant material is used recreationally as a stupefacient and has a purported medicinal use. In fact, anecdotal information about its medicinal properties has been such that Health Canada has recently started an initiative to provide a well characterized supply of plant tissue to researchers interested in examining its potential medicinal properties. Simultaneously this same material is being provided for those subjects who are licensed to use marihuana as a medicine. <p>In order to further study marihuana and its component cannabinoids it is essential to be able to discern both the cannabinoid content in the product being supplied and more importantly the cannabinoid profile in the delivery system. At present the most common route of administration is via inhalation of the combusted plant material. Consequently methods capable of measuring the cannabinoid content in combusted plant material would be very useful in order to make meaningful study of the pharmacokinetics of the cannabinoids delivered by this route. <p>Investigations were carried out to develop a method and study the volatile constituents of combusted marihuana plant material in a semi-enclosed environment. Thus the hypothesis of this research is that qualitative and quantitative information can be obtained from the combustion products of cannabis plant tissue. The method relies upon the solid phase extraction of smoke arising from the combustion of plant material in a variety of combustion chambers. The combustion chambers were designed to reflect the current marihuana paraphernalia in use as well as a high efficiency in vitro system. Both the qualitative and quantitative levels of a limited number of cannabinoids were evaluated before and after combustion. A quantitative Liquid Chromatography Ultra Violet (LC-UV) detector method was validated for the analysis of a selected group of cannabinoids ( Δ9-tetrahydrocannabinol (THC), cannabinol (CBN), cannabidiol (CBD) and tetrahydrocannabinolic acid (THCA) . When this method was applied to plant material available through the medical marijuana initiative the following observations were made on the combustion products:<p> <table style="text-align: left; width: 397px;" border="1" cellpadding="2" cellspacing="2"> <tbody> <tr> <td style="width: 119px;">Material</td> <td style="width: 59px;">CBD</td> <td style="width: 59px;">CBN</td> <td style="width: 59px;">THC</td> <td style="width: 59px;">THCA</td> </tr> <tr> <td style="width: 119px;">Analyzed</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> <td style="width: 59px;">(ug/ml)</td> </tr> <tr> <td style="width: 119px;">Plant</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">BLQ</td> <td style="width: 59px;">890</td> </tr> <tr> <td style="width: 119px;">Combusted</td> <td style="width: 59px;">20</td> <td style="width: 59px;">14</td> <td style="width: 59px;">420</td> <td style="width: 59px;">28</td> </tr> </tbody> </table> 5 mg plant tissue extracted using a validated HPLC-UV method <p> 5 mg plant tissue combusted in a closed combustion chamber.<p> BLQ: below level of quantification (<12.5 ug/mL)<p>These results sparked further research into the quantitative transformation of cannabinoids during the combustion process. In this regard, it was shown that THC, CBD and CBN all could be recovered at approximately a 90% ratio upon combustion However, THCA was thermally converted such that very little remains after combustion and furthermore, its degradation product, THC can only account for 50% of the THCA. The latter observation is important since there has been a prevailing thought that THCA is quantitatively transformed during combustion to THC while in fact this transformation is approximately 50%. This finding must be considered when pharmacokinetic studies are carried out using inhalation of combusted plant material as the delivery system.<p>A further finding of this research is that not all popular combustion devices yield identical quantitative cannabinoid profiles. In this regard, the simpler pipe systems result in the highest yields of heat transformed cannabinoids while the vaporizer systems have the lowest cannabinoid yields.

Accessible in vitro models recapitulating the human airway that are amenable to study whole cannabis smoke exposure are needed for immunological and toxicological studies that inform public health policy as well as medicinal and recreational cannabis use. In the present study, we developed and validated a novel three-dimensional (3D)-printed in vitro exposure system (IVES) that can be directly applied to study the effect of cannabis smoke exposure on primary human bronchial epithelial cells (HBECs). Using commercially available design software and a 3D printer, we designed a four-chamber Transwell insert holder for exposures to whole smoke. COMSOL Multiphysics software was used to model gas distribution, concentration gradients, velocity profile, and shear stress within IVES. Following simulations, primary HBECs cultured at the air–liquid interface on Transwell inserts were exposed to whole cannabis smoke using a modified version of the Foltin puff procedure. Following 24 h, outcome measurements included cell morphology, epithelial barrier function, lactate dehydrogenase (LDH) levels, cytokine expression and gene expression. HBECs exposed to cannabis smoke using IVES showed changes in cell morphology and disruption of barrier function without significant cytotoxicity. Cannabis smoke elevated interleukin-1 (IL-1) family cytokines and elevated CYP1A1 and CYP1B1 expression relative to control. These findings validate IVES to have an effect in HBECs at a molecular level following cannabis smoke exposure. In addition, HBECs stimulated with a viral mimetic, Poly I:C, challenge following cannabis smoke exposure showed a suppression of key antiviral cytokines. The growing legalization of cannabis on a global scale must be paired with research related to potential health impacts on lung exposures. IVES represents an accessible, open-source, exposure system that can be used to model varying types of cannabis smoke exposures with HBECs grown under air–liquid interface culture conditions. / Thesis / Master of Science (MSc) / Despite its recent legalization in Canada, cannabis smoke has been understudied and a lack of evidence exists to inform legislative policies, medicinal and recreational usage. Due to a lack of relevant ways to study cannabis smoke in a lab setting, it is difficult to accumulate literature around its impacts in the lungs. Here, we addressed this gap by engineering and validating a novel model to expose lung cultures to cannabis smoke. In addition, we investigated its impact on the immune response. Our findings suggest exposure to cannabis smoke alters the immune functions of these cells. We also found that in response to a viral mimetic stimulus, cell cultures pre-exposed to cannabis smoke exhibited impaired immune responses. Our novel model to expose cell cultures to cannabis smoke creates a foundation for future researchers to investigate environmental insults, such as cannabis smoke, in the context of respiratory health and infectious disease.