ABSTRACT
This review summarizes the protective effects of probiotics against Alzheimer's disease (AD), one of the most common neurodegenerative disorders affecting older adults. This disease is characterized by the deposition of tau and amyloid ß peptide (Aß) in different parts of the brain. Symptoms observed in patients with AD include struggles with writing, speech, memory, and knowledge. The gut microbiota reportedly plays an important role in brain functioning due to its bidirectional communication with the gut via the gut-brain axis. The emotional and cognitive centers in the brain are linked to the functions of the peripheral intestinal system via this gut-brain axis. Dysbiosis has been linked to neurodegenerative disorders, indicating the significance of gut homeostasis for proper brain function. Probiotics play an important role in protecting against the symptoms of AD as they restore gut-brain homeostasis to a great extent. This review summarizes the characteristics, status of gut-brain axis, and significance of gut microbiota in AD. Review and research articles related to the role of probiotics in the treatment of AD were searched in the PubMed database. Recent studies conducted using animal models were given preference. Recent clinical trials were searched for separately. Several studies conducted on animal and human models clearly explain the benefits of probiotics in improving cognition and memory in experimental subjects. Based on these studies, novel therapeutic approaches can be designed for the treatment of patients with AD.
ABSTRACT
Rats have inherent licking behavior and responses to good and aversive tasting stimuli, which are comparable to humans. Taste masking of chewable and orodispersible tablets of an iron EDTA complex salt was evaluated using rat behavioral avoidance model, brief access test. Taste-masked chewable and orodispersible tablets of iron EDTA complex were prepared using various flavors and sweeteners as taste-masking agents. These formulations were presented to rats and their responses were recorded in terms of licking frequency and other avoidance responses. Formulations were also presented to human volunteers and a correlation between responses of humans and rats was tried to be established. Taste responses of rats were found to be similar to those of humans. A high correlation between the taste responses of rats and humans was observed. Evaluation of taste masking using human panels presents several difficulties such as ethical concerns, fatigue and subjectivity. Thus, rat behavioral avoidance model can be considered as a good alternative to taste assessment by human volunteers for further such investigations.
