A comparative study of anti-aging effects of Carica papaya (pulp and seeds) on D-galactose-induced brain aging in albino rats

BACKGROUND AND AIM: The brain is one of the most complex and crucial organs of our body. Its health is a matter of concern for all individuals as the number of aged people is increasing gradually in the world. Carica papaya is a ubiquitous plant, and its different parts possess neuroprotective effects against various neurodegenerative diseases. However, its brain anti-aging effects have remained uninvestigated. Therefore, this study has examined the brain anti-aging strength of C. papaya pulp and seeds extracts in D-galactose-induced aging rats. METHODS: The rats were intraperitoneally injected with 150 mg/kg of D-galactose for 8 consecutive weeks to induce brain aging. In parallel, the rats of papaya pulp and papaya seed treated groups were injected with 150 mg/kg papaya pulp extract and 150 mg/kg papaya seed extract, respectively. The negative control group was only injected with 0.9% saline, whereas in the rats of the positive control group along with D-galactose 100 mg/kg VC was injected. After the treatment period, different neurobehavioral, neurochemical, and antioxidant analyses were performed to unmask the anti-aging strength of C. papaya pulp and seeds extracts. RESULTS: C. papaya pulp and seed extracts significantly improved cognitive learning skills, memory, and muscular strength in aging rats while reducing stress and anxiety levels. Moreover, they enhanced neurotransmitters concentration and reduced oxidative stress. However, the anti-aging effects of C. papaya pulp were more significant than seeds. CONCLUSION: These results suggest that both C. papaya pulp and seed extracts possess neuroprotective effects against brain aging or age-related brain deteriorations but the age-protecting capability of C. papaya pulp is higher than C. papaya seeds. Therefore, it could be utilized as a component to design a novel brain anti-aging drug. RELEVANCE FOR PATIENTS: Brain aging is a natural process that every individual experiences in his life. The regular consumption of C. papaya can improve the quality of life by protecting neurons from age-related deteriorations.