Parallel Studies in Mice and Men by Using QST and Non-Evoked Pain Measures

Translation from preclinical rodent animal models to patients are hindered by several aspects including the use of non-relevant pain models and a mismatch between pain-related outcomes in preclinical and clinical studies, which will be discussed. First, relevant preclinical pain models (incisional, cancer – related and neuropathic pain model) will be discussed including advantages and disadvantages and ways to improve their translational value. Secondly, multidimensional behavioral outcome measures that objectively and reproducibly assess clinically relevant pain-related symptoms in rodent will be discussed. From a historical perspective, evoked pain-related behaviors are assessed by determining withdrawal reactions to externally applied mechanical and thermal stimuli to the hind paw of rodents. However, these assessments are not only prone to experimental bias; they also encompass mainly the somatosensory (spinal reflex) pathways and miss the complex cognitive and emotional as well as voluntary components of pain. In contrast, multidimensional behavioral outcome measures in preclinical settings presumably capturing clinically relevant symptoms might improve translation. This talk will present recent advantages in preclinical (rodent) pain assessment methods such as pain-related gait changes, non-evoked pain-related behavior assessments, and video-based methods for assessing pain-related outcomes. Finally, parallel laboratory results from preclinical and clinical studies will be presented.