Research Article Nootropic Effects of C. melo and C. lanatus seed extracts Shahana Wahid, 1 Ali Alqahtani, 2 and Rafeeq Alam Khan 1,3 1 Department of Pharmacology, University of Karachi, Karachi, Pakistan 2 Department of Pharmacology, College of Pharmacy, King Khalid University, Guraiger, Abha 62529, Saudi Arabia 3 Faculty of Pharmacy, Ziauddin University, Karachi, Pakistan Correspondence should be addressed to Rafeeq Alam Khan; rkhan1959@gmail.com Received 16 September 2020; Revised 31 October 2020; Accepted 3 December 2020; Published 10 December 2020 Academic Editor: Kazim Husain Copyright © 2020 Shahana Wahid et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Dementia and related conditions disturb the ability to perform routine life activities prohibiting a person from making appropriate decisions. Seeds of Cucumis melo and Citrullus lanatus have been investigated extensively for various pharmacological properties; hence, considering the presence of bioactive compounds, it was assumed that these seed extracts may support the functioning of the central nervous system. Thus, the present study was designed to investigate the short-term and long-term memory-enhancing effects of C. melo and C. lanatus seed extracts in mice by the Morris water maze (spatial learning and memory), stationary rod test, and passive avoidance tests (fear-motivated tests). Ethanol extract of both seeds were prepared by standard procedure and given to animals in the doses of 50 mg/kg, 100 mg/kg, and 200 mg/kg. The results were compared to standard drugs diazepam and imipramine given in the doses of 3 mg/kg and 30 mg/kg, respectively. Extracts of both the seeds were found to possess significant memory and cognition-enhancing effects in mice when tested by passive avoidance, stationary rod, and water maze tests. Results demonstrate memory and cognition-enhancing effects of these extracts which may be due to the presence of bioactive compounds in these seeds. 1. Introduction Dementia and related conditions disturb the ability to per- form routine life activities prohibiting a person from making appropriate decisions. Learning and memory evaluation is the most tested paradigm which explores the effect of drugs on certain regions of the brain according to the model selected. Learning is the process of attainment of new mem- ories while memory is the recalling of past learned events. It involves encoding, storage, retrieval, and forgetting [1]. Short-term memory is defined as memory over a short time interval while long-term memory refers to the retention of information for a prolonged period of time. Long-term mem- ory is developed due to periodic repetition of information [2]. The normal learning process depends on neurotransmitters like acetylcholine, dopamine, and 5HT which activate the hippocampus (new learning) and amygdala (fear and emo- tional memories) and other brain areas such as the primary sensory cortex, visual cortex, and auditory cortex [3]. The loss of memory is greatly accelerated by anxiolytics, sedatives, or substances of abuse which result in amnesia. However, cholinesterase inhibitors and dopamine agonists are used to treat dementia [4]. Alzheimer is a neurodegenerative disease with many neu- ropsychiatric and cognitive problems causing progressive disability and dementia. The condition is either due to the loss of cholinergic neurons especially in the forebrain or reduction in concentration of acetylcholine. The most hope- ful treatment for AD is the use of enzyme acetyl cholinester- ase (AChE) inhibitors which mainly produce effects by increasing acetyl choline concentration in the brain. How- ever, drugs which improve memory will have a beneficial effect in Alzheimer’s disease (AD). Various plants have been used traditionally for management of many diseases due to the presence of bioactive compounds; thus, extracts from C. melo and C. lanatus may lead to discovery of new compounds. Cucumis melo seeds are a rich source of minerals; vitamins; and enzyme inhibitors like magnesium, potassium, calcium, and sodium [5]; vitamin A; vitamin C; cucurbitacin Hindawi BioMed Research International Volume 2020, Article ID 8823038, 7 pages https://doi.org/10.1155/2020/8823038