Experimental Injury Rodent Models for Oropharyngeal Dysphagia

SIMPLE SUMMARY: Dysphagia is a symptom of difficulty in carrying food safely from the mouth to the stomach. Recently, the number of people complaining of discomfort in swallowing due to various causes increased. In order to develop an appropriate treatment for them, experimentally induced dysphagia rodent models that mimic human dysphagia have recently been developed. Therefore, in this study, the rodent models of oropharyngeal dysphagia reported so far was summarized. The article search was conducted using Medline, Embase, and Cochrane Library. For this study, 13 articles that reported an experimentally induced oropharyngeal dysphagia in rodents were selected. The following information was collected: injury type, animal type, induction protocol of dysphagia, main defects, and dysphagia screening. Advances in basic research using animal studies are paving the way for intensive research and active therapeutic strategies for patients with swallowing disorders. The information would be the basis for pre-clinical trials to overcome oropharyngeal dysphagia. ABSTRACT: Oropharyngeal dysphagia is a disorder that can make swallowing difficult and reduce the quality of life. Recently, the number of patients with swallowing difficulty has been increasing; however, no comprehensive treatment for such patients has been developed. Various experimental animal models that mimic oropharyngeal dysphagia have been developed to identify appropriate treatments. This review aims to summarize the experimentally induced oropharyngeal dysphagia rodent models that can be used to provide a pathological basis for dysphagia. The selected studies were classified into those reporting dysphagia rodent models showing lingual paralysis by hypoglossal nerve injury, facial muscle paralysis by facial nerve injury, laryngeal paralysis by laryngeal and vagus nerve injury, and tongue dysfunction by irradiation of the head and neck regions. The animals used in each injury model, the injury method that induced dysphagia, the screening method for dysphagia, and the results are summarized. The use of appropriate animal models of dysphagia may provide adequate answers to biological questions. This review can help in selecting a dysphagia animal system tailored for the purpose of providing a possible solution to overcome dysphagia.