IN SILICO, IN VITRO AND IN VIVO MEMORY ENHANCING ACTIVITY OF CERTAIN COMMERCIALLY AVAILABLE FLAVONOIDS IN SCOPOLAMINE AND ALUMINIUM-INDUCED LEARNING IMPAIRMENT IN MICE Thesis submitted to The Tamil Nadu Dr. M.G.R. Medical University, Chennai for the award of the degree of DOCTOR OF PHILOSOPHY in PHARMACY Submitted by A. MADESWARAN, M. Pharm., Under the guidance of Dr. K. ASOK KUMAR, M. Pharm., Ph.D. College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore – 641 044, Tamil Nadu, India. JUNE 2017 Certificate This is to certify that the Ph.D. dissertation entitled “IN SILICO, IN VITRO AND IN VIVO MEMORY ENHANCING ACTIVITY OF CERTAIN COMMERCIALLY AVAILABLE FLAVONOIDS IN SCOPOLAMINE AND ALUMINIUM- INDUCED LEARNING IMPAIRMENT IN MICE” being submitted to The Tamil Nadu Dr. M.G.R. Medical University, Chennai, for the award of degree of DOCTOR OF PHILOSOPHY in the FACULTY OF PHARMACY was carried out by Mr. A. MADESWARAN, in College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore, under my direct supervision and guidance to my fullest satisfaction. The contents of this thesis, in full or in parts, have not been submitted to any other Institute or University for the award of any degree or diploma. Dr. K. Asok Kumar, M.Pharm., Ph.D. Professor & Head, Department of Pharmacology, College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore, Tamil Nadu - 641 044. Place: Coimbatore – 44. Date: Certificate This is to certify that the Ph.D. dissertation entitled “IN SILICO, IN VITRO AND IN VIVO MEMORY ENHANCING ACTIVITY OF CERTAIN COMMERCIALLY AVAILABLE FLAVONOIDS IN SCOPOLAMINE AND ALUMINIUM- INDUCED LEARNING IMPAIRMENT IN MICE” being submitted to The Tamil Nadu Dr. M.G.R. Medical University, Chennai, for the award of degree of DOCTOR OF PHILOSOPHY in the FACULTY OF PHARMACY was carried out by Mr. A. MADESWARAN, in College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore, under my co-guidance to my fullest satisfaction. The contents of this thesis, in full or in parts, have not been submitted to any other Institute or University for the award of any degree or diploma. Dr. Sonia George, M. Pharm., Ph.D. Assistant Professor, Dept. of Pharmaceutical Chemistry, College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore, Tamil Nadu - 641 044. Place: Coimbatore - 44 Date: Certificate This is to certify that the Ph.D. dissertation entitled “IN SILICO, IN VITRO AND IN VIVO MEMORY ENHANCING ACTIVITY OF CERTAIN COMMERCIALLY AVAILABLE FLAVONOIDS IN SCOPOLAMINE AND ALUMINIUM- INDUCED LEARNING IMPAIRMENT IN MICE” being submitted to The Tamil Nadu Dr. M.G.R. Medical University, Chennai, for the award of degree of DOCTOR OF PHILOSOPHY in the FACULTY Of PHARMACY was carried out by Mr. A. MADESWARAN under the direct supervision and guidance of Dr. K. ASOK KUMAR, M. Pharm., Ph.D. and the co-guidance of Dr. SONIA GEORGE, M. Pharm., Ph.D. in College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore. Dr. T.K. Ravi, M.Pharm., Ph.D., FAGE. Principal, College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore, Tamil Nadu - 641 044. Place: Coimbatore - 44 Date: Declaration I hereby declare that the Ph.D. dissertation entitled “IN SILICO, IN VITRO AND IN VIVO MEMORY ENHANCING ACTIVITY OF CERTAIN COMMERCIALLY AVAILABLE FLAVONOIDS IN SCOPOLAMINE AND ALUMINIUM- INDUCED LEARNING IMPAIRMENT IN MICE” being submitted to The Tamil Nadu Dr. M.G.R. Medical University, Chennai, for the award of degree of DOCTOR OF PHILOSOPHY in the FACULTY OF PHARMACY was carried out by me under the direct supervision and guidance of Dr. K. ASOK KUMAR, M. Pharm., Ph.D. and the co- guidance of Dr. SONIA GEORGE, M. Pharm., Ph.D. in College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore. The contents of this thesis, in full or in parts, have not been submitted to any other Institute or University for the award of any degree or diploma. A. Madeswaran Place: Coimbatore -44 Date: ACKNOWLEDGEMENTS Apart from my efforts, the success of this thesis depends largely on the encouragement and advice of many others. I take this opportunity to express my gratitude to the people who have been involved in the successful completion of this research work. I wish to express my most sincere gratitude to my guide Dr. K. Asok Kumar M. Pharm., Ph.D. Professor and Head, Department of Pharmacology, College of Pharmacy, SRIPMS, Coimbatore and it is my duty to thank him, for his constant support, help, guidance, encouragement and ultimately inspiration. I take this opportunity to accord my sedulous gratitude to my beloved co-guide Dr. Sonia George, M.Pharm., Ph.D. Assistant Professor, Department of Pharmaceutical Chemistry, for her valuable guidance and moral support throughout the period of my study. I express my heartfelt thanks to Prof. Dr. T.K. Ravi, Principal, College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore for providing me this chance, for his kind and constant support and timely guidance in the completion of this work. I am elated to keep on record my indebtedness and thankfulness to our beloved Managing Trustee Shri. R. Vijayakumhar and the Joint Managing Trustee Shri. D. Lakshminarayanaswamy, former Managing Trustees, Shri. C. Soundararaj and Sevaratna Dr. R. Venkatesalu Naidu and the Management for permitting me and providing all the facilities to carry out this project. I am greatly thankful to Dr. M. Gopal rao, Vice-Principal, College of Pharmacy, SRIPMS for his kind support and timely help in the completion of this work. I am greatly expressing my acknowledgement of gratitude to my well- wisher Dr. M. Uma Maheswari, for her consent, endurance and help in completing this thesis work on time. I also extend my heartfelt thanks to Dr. B. Rajalingam, Dr. P. Bharathi, Dr. A.T. Sivashanmugam, Dr. S. Krishnan, Dr. M. Gandhimathi, Dr. J. Bagyalakshmi and Mr. Sunnapu Prasad for their constant support, endurance and help in completing this thesis work on time. I also extend my heartfelt gratitude to Dr. S. Sriram, Prof. M. Francis Saleshier and Dr. R. Vijayaraj for their valuable guidance for the successful completion of this task on time. I extend my deep sense of gratitude to my colleagues Dr. A.S. Manjuladevi, Dr. Beena S Menon, Dr. R.M. Akhila, Dr. R. Jayaprakasam, Mrs. V. Subhadra Devi, Dr. A. Suganthi, Mrs. R. K. Sangeetha, Dr. S. Lakshmidevi, Mrs. M. Dhanamani, Mr. V. Shivashankar and Mr. P. Jagannath for their help, support and best wishes offered, which helped me a lot in completing this work. I would like to express my thanks to Mrs. R. Vathsala, Store In- charge for helping me in timely acquiring the required chemicals. I extend my gratitude to Mrs. A. Nirmala, Office In-charge. I take this opportunity, with pride and immense pleasure in expressing my heartfelt thanks to Mr. John, Mrs. Dhanalakshmi, Dr. R. Venkataswamy for their skilled technical assistance and for their timely help during this research work and also to the lab attendants Mrs. R. Rajeswari, Mrs. Karpagam, Mrs. Kalaivani, Mr. Murganantham, Mrs. Beula Hepsibah, Mrs. F. Stella and Mrs. Vanitha for their support in the due course of this work. I would like to thank all other teaching and non-teaching faculties of this institution and other friends whose name I might have not spelt it here, for their direct or indirect help in completing this work. I’m acknowledging my family members D. Parameswaran, P. Jamuna, A. Srinivasan, and S. Shanthi for their prayers and also I would like to express my gratitude to P. Dhanush, P. Harish ram, S. Jaisurya and S. Lidhiksha which will be always be remembered. I’m greatly indebted forever to my lovely wife M. Pradeepa for her care, prayers, encouragement and the support rendered throughout my tough times and tremendous patience, understanding and inestimable help which will be always be remembered. Finally, I would be ever indebted to the two persons who had given me life and brought me to this level. First, my beloved Mother and second my beloved Father. A. MADESWARAN Contents Page S. No. Chapters No. Abbreviations List of Tables List of Figures 1. Introduction 1 1.1 Neurodegenerative disorders 1 1.1.1 Overview of dementia 1 1.2 Types of dementia 2 1.2.1 Alzheimer’s disease 2 1.2.2 Vascular dementia 2 1.2.3 Dementia with Lewy bodies (DLB) 2 1.2.4 Fronto-temporal lobar degeneration (FTLD) 3 1.2.5 Mixed dementia 3 1.2.6 Creutzfeldt-Jakob disease 3 1.2.7 Parkinson’s disease (PD) dementia 3 1.2.8 Normal pressure hydrocephalus 4 1.3 Alzheimer's disease (AD) 4 1.3.1 History of Alzheimer’s disease 4 1.3.2 Neurotransmitters in AD 5 1.3.3 Signs of AD 5 1.3.4 Clinical facts of AD 6 1.3.5 Etiology of AD 6 1.3.6 Stages of AD 7 1.3.7 Pathophysiology of AD 9 1.3.8 Acetylcholine 13 1.3.9 Synthesis, storage and release of acetylcholine 13 1.3.10 Management of AD 14 1.3.11 Alzheimer’s disease inducing agents 16 1.4 Drug discovery and development 20 1.4.1 Drug design 20 1.4.2 Types of drug design 20 1.4.3 Molecular docking 22 1.4.4 Identification of right target and active site 22 Contents 1.4.5 Lipinski’s rule of Five 23 1.4.6 Types of docking 23 1.4.7 Docking approaches 23 1.4.8 Mechanics of docking 24 1.4.9 Scoring functions 26 1.4.10 Various docking software’s used for molecular 27 docking 1.4.11 Applications of drug design 31 1.5 Flavonoids 31 1.5.1 Structure of flavonoids 31 1.5.2 Classification of flavonoids 32 1.5.3 Pharmacological activity of flavonoids 32 2.