en Clinical Neuroscience Clinical Neuroscience Original Original <div style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:Tahoma;"><span style="line-height:2;"><strong>Introduction</strong>: Alzheimer disease (AD) is a progressive neurodegenerative disease that accounts for 60% of dementia cases worldwide. Despite the lack of concrete information about the prevalence of dysphagia among AD patients, it still significantly impairs their quality of life (QoL). That outcome necessitates more investigations to understand the pathophysiology of this condition and how to manage it. In this study, we examined if AD-associated changes in pharyngeal and tongue muscles could explain dysphagia.<br> <strong>Methods</strong>: Fourteen adult male rats were allocated into 2 groups: Group I (control) received distilled water orally, group II (AD) received aluminum chloride (AlCl3) (200 mg/kg, per os) and D-galactose (60 mg/kg, subcutaneous) daily for 45 days. Biochemical parameters were conducted, including amyloid beta-peptide (A&beta;), histopathological investigation of the hippocampus, tongue, and pharynx, and immune-histochemical expression of brain glial fibrillar acidic protein (GFAP).<br> <strong>Results</strong>: Our AD model showed marked cognitive impairment, hippocampal oxidative stress, and increased brain A&beta; expression (P=0.0003) compared to controls. Dysphagia was confirmed by loss of body weight (P=0.0077) and decreased eating and drinking patterns by 25%-35% in AD versus the control group. Histopathological, immune-histochemical, and biochemical evidence, including increased levels of pharyngeal A&beta; (P=0.0017), were detected in AD rats&rsquo; tongue and pharyngeal muscles.&nbsp;<br> <strong>Conclusion</strong>: Dysphagia in AD can result not only centrally but also due to local involvement of the tongue and pharynx. Further translational studies linking dysphagia to AD pathology will be needed.</span></span></span></div> Alzheimer disease (AD), Dysphagia, Amyloid, Tongue, Pharyngeal muscles 671 682 http://bcn.iums.ac.ir/browse.php?a_code=A-10-5719-1&slc_lang=en&sid=1 Ramy Abdelnaby rabdelnaby@ukaachen.de 13700319475328460050714 13700319475328460050714 Yes Department of Neurology, RWTH Aachen University, Aachen, Germany. Yasmine H. Ahmed yasmine_hamdi@cu.edu.eg 13700319475328460050715 13700319475328460050715 No Department of Cytology and Histology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt. Dalia Zaafar dalia.zaffar@pharm.mti.edu.eg 13700319475328460050716 13700319475328460050716 No Department of Pharmacology and Toxicology, Faculty of Pharmacy, Modern University for Information and Technology, Cairo, Egypt. Mohamed Y. Mahmoud mohamed_yehia@cu.edu.eg 13700319475328460050717 13700319475328460050717 No Department of Toxicology, Forensic Medicine and Veterinary Regulations, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt. Eman Mohammed Elsaeed eman.mohamed@med.psu.edu.eg 13700319475328460050718 13700319475328460050718 No Department of Human Anatomy and Embryology, Faculty of Medicine, Port Said University, Port Said, Egypt. Alexa Häger ahaeger@ukaachen.de 13700319475328460050719 13700319475328460050719 No Department of Neurology, RWTH Aachen University, Aachen, Germany. Heba M. A. Khalil heba.ali@cu.edu.eg 13700319475328460050720 13700319475328460050720 No Department of Veterinary Hygiene and Management, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt.