Background Dementia is a leading cause of disability and dependency in elderly people, generating significant physical, psychological, and financial challenges for patients, caregivers, and healthcare systems worldwide. For Alzheimer’s disease (AD), the most common form of dementia, established treatments such as Acetyl-Cholinesterase Inhibitors (AChE) have proven to be marginally beneficial, but side effects remain. Alternatively, a standardized preparation of Ginkgo Biloba Extract (EGb-761) is a popular herbal medicine used globally and widely available in Hong Kong. This paper reviews and synthesizes the effectiveness of EGb-761 in the treatment of AD compared to placebo and AChE treatments. Methods A systematic search was performed using PubMed, ProQuest, and Google Scholar to identify all relevant randomized controlled studies in English that examined the effectiveness of EGb-761 on individuals with AD. The studies, based on expert consensus, had to have a minimum duration of 22 weeks and one of two primary outcome measures: 1. cognitive functioning, 2. functional ability in activities-of-daily-living (ADL). A secondary outcome measure, safety (drop-out rate from adverse events), was also evaluated. Quality was assessed based on indicators derived from the CONSORT 2010 checklist. Findings Ten randomized controlled trials from eight countries, with participants ranging from mild to severe AD were included. Of the ten studies, eight compared EGb-761 with placebo, three compared EGb-761 head-to-head with an AChE (two with Donepezil, one with Rivastigmine), and one compared EGb-761 and AChE stand-alone treatment with combined treatments (EGb-761 + AChE). Overall results on cognitive and functional improvements were mixed. Of the studies that demonstrated a positive association, the clinical significance is questionable. Conclusions Although results were inconsistent, EGb-761’s safety appears to be acceptable. In Hong Kong, given the widespread availability, popularity and perceived safety of EGb-761, the population needs appropriate guidance and support from the government to safeguard quality and increase awareness of potential drug-herb interactions. Concurrently, with AChE becoming an increasingly established treatment for AD, more head-to-head studies on EGb-761 and AChE on the local population are needed to increase understanding and public awareness. / published_or_final_version / Public Health / Master / Master of Public Health

Alzheimer's disease has become one of the most common diseases jeopardizing the health of the human being. The main pathological feature of AD is the accumulation of Aβ in the brain to form senile plaques. Therefore, it is of great significance to develop new and efficient drugs targeting at amyloid-β for the detection, diagnosis and therapeutics for Alzheimer's disease. Xanthohumol (Xn) naturally presents in hops (Humulus lupulus L). Studies have shown that it has anti-lipoperoxidative, anti-inflammatory, anti-proliferative activities, antiangiogenic and antioxidant effects, which further illustrates its potential therapeutic for AD. However, the bio-incompatibility and blood-brain barrier impermeability of Xanthohumol hindered it in vivo efficacy potential for treating Alzheimer's disease. Thus, we designed and prepared a series of Xanthohumol derivatives, namely, Xn-n, (n = 1-9) and its chalcone derivatives C-n, (n = 1-10) to enhance the desirable physical, biological and pharmacological properties, especially the blood-brain barrier permeability for intervention of AD. As an effective technique for in vivo visualization, Near-infrared fluorescence imaging based on organic small molecule probes has a promising application in the diagnosis of Alzheimer's disease. However, most of the reported imaging probes can only visualize Aβ-plaques but do not have therapeutic potential such as neuroprotection against Aβ induced toxicity. Herein, we designed and synthesized a series of oligomeric Aβ targeted near infrared (NIR) fluorescent probes for the diagnosis and therapeutics of Alzheimer's disease, namely DBAN-SLM, DBAN-SLOH, DBAN-OSLM which showed remarkably effective inhibitory effect on Aβ aggregation, significant neuroprotection effect against the Aβ-induced toxicities, and suppression on Aβ-induced ROS generation. indicating its great promise as a useful theragnostic agent for the early diagnosis and therapy of AD. Dual-modal imaging is an important approach to overcome the limitations of single imaging technology in the diagnosis of AD disease. Therefore, based on the dual-modal, we designed and synthesized the NIR/MR dual-modal detection and theragnostic probes namely Dyad-1, Dyad-2, Dyad-3 and NP@SiO2@F-SLOH. More surprising is that the two NIR/MR dual-modal probes show excellent biological properties, including the ability to inhibit Aβ aggregation to a certain extent, neuroprotective effects on cytotoxicity caused by different forms of Aβ species, blood-brain barrier (BBB) permeability, and high stability. All of these newly designed and synthesized molecules were characterized with 1H NMR, 13C NMR, and HRMS and found to show good agreement with the desired structures. The photophysical properties and biological properties of these novel designed and synthesized fluorescent probe such as UV-vis absorption, fluorescence emission, dissociation constant determined by fluorescence titration, cytotoxicity assay, neuroprotection, and inhibition of Aβ aggregation were investigated

Alzheimer's disease is a progressive neurodegenerative disorder, in which there is a marked decline in neurotransmitters, especially those of the cholinergic pathways. One of the approaches to the symptomatic treatment of Alzheimer's disease is the inhibition of the breakdown of the neurotransmitter acetylcholine, using an acetylcholinesterase inhibitor. One such drug tested, is the organophosphate, metrifonate. Any drug used for the treatment of neurodegenerative disorders should preferably not induce further neurological damage. Thus, in the present study, we investigated whether or not metrifonate is neuroprotective. The in vivo and in vitro effect of this drug on free radicals generation shows that metrifonate increases the level ofthese reactive species. Lipid peroxidation induced using quinolinic acid (QA) and iron (II) and show that metrifonate increased the peroxidative damage induced by using quinolinic acid. Metrifonate is also able to induce lipid peroxidation both in vivo and in vitro. This was reduced in vitro in the presence of melatonin. Using iron (II), in vi/ro, there was no significant difference in the level of lipid peroxidation in the presence of this drug. An investigation of the activity of the mitochondrial electron transport chain and complex I of the electron transport chain in the presence of metrifonate revealed that metrifonate reduces the activity of the electron transport chain at the level of complex I. The activity of the mitochondrial electron transport chain was restored in the presence of melatonin. Pineal organ culture showed that metrifonate does not increase melatonin production. Histological and apoptosis studies show that tissue necrosis and apoptosis respectively, occur in the presence of this agent, which is reduced in the presence of melatonin. Metal binding studies were performed USing ultraviolet spectroscopy, and electrochemical analysis to examine the interaction of metrifonate with iron (II) and iron (III). No shift in the peak was observed in the ultraviolet spectrum when iron (ll) was added to metrifonate. Electrochemical studies show that there may be a very weak or no ligand formed between the metal and drug. This study shows that while drugs such as metrifonate may be beneficial in restoring cognitive function in Alzheimer's disease, it could also have the potential to enhance neurodegeneration, thus worsening the condition, in the long term. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

The potent analgesic property of acetylsalicylic acid and acetaminophen makes these the most commonly used analgesics in the world. Easy accessibility and cost effectiveness of these agents are attractive to patients seeking pain relief. However, the abuse of nonnarcotic analgesics such as acetaminophen and acetylsalicylic acid by alcoholics and patients seeking to relieve dysphoric moods is well documented. These agents therefore impact on the brain neurotransmitter levels and therefore all processes involved in the synthesis and metabolism of neurotransmitters may be affected. The use of non-narcotic analgesics has been reported to reduce the incidence of neurodegenerative disorders such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). The mode of action by which acetylsalicylic acid and acetaminophen elicit neuroprotection is however unclear as many mechanisms of action have been inconclusively postulated. The first part of this study aims to elucidate the various mechanisms by which acetylsalicylic acid and acetaminophen affect the enzymes responsible for the catabolism of tryptophan, which is a precursor for the mood elevating neurotransmitter serotonin, as well as to investigate whether these agents alter the interplay between serotonin and pineal indole metabolism. The second part of this study focuses on the neuroprotective properties of acetylsalicylic acid and acetaminophen utilizing the neurotoxic metabolite of the kynurenine pathway, quinolinic acid and the potent Parkinsonian neurotoxin, 1-methyl-4-phenylpyridinium (MPP+). The ability of acetylsalicylic acid and acetaminophen to alter TRP metabolism was determined by investigating the effects of these agents on the primary enzymes of the kynurenine pathway i.e. tryptophan 2, 3-dioxygenase and indoleamine 2,3-dioxygenase as well as to investigate whether these agents would have any effects on 3-hydroxyanthranilic acid oxygenase. 3-Hydroxyanthranilic acid oxygenase is the enzyme responsible for the synthesis of quinolinic acid. Acetylsalicylic acid and acetaminophen alter tryptophan metabolism by inhibiting tryptophan 2, 3-dioxygenase and indoleamine 2,3-dioxygenase thus increasing the availability of tryptophan for the production of serotonin. Acetylsalicylic acid and acetaminophen also inhibit 3-hydroxyanthranilic acid oxygenase thus implying that these agents could reduce quinolinic acid production. Acetaminophen administration in rats induces a rise in serotonin and norepinephrine in the forebrain. Acetylsalicylic acid curtails the acetaminophen-induced rise in brain norepinephrine levels as well as enhances serotonin metabolism, indicating that analgesic preparations containing both agents would be advantageous, as this would prevent acetaminophen-induced mood elevation. The results from the pineal indole metabolism study show that acetylsalicylic acid enhances pineal metabolism of serotonin whereas acetaminophen induces an increase in melatonin levels in the pineal gland. Neuronal damage due to oxidative stress has been implicated in several neurodegenerative disorders such as AD and PD. The second part of the study aims to elucidate and characterize the mechanism by which acetylsalicylic acid and acetaminophen afford neuroprotection. The hippocampus is an important region of the brain responsible for memory. Agents such as quinolinic acid that are known to induce stress in this area have detrimental effects and could lead to various types of dementia. The striatum is also a vulnerable region to oxidative stress and hence (MPP+), which is toxic for this particular region of the brain, was also used as a neurotoxin. The results show that ASA and acetaminophen alone and in combination, are potent superoxide anion scavengers. In addition, the results imply that these agents offer protection against oxidative stress and lipid peroxidation induced by several neurotoxins in rat brain particularly, the hippocampus and striatum. Histological studies, using Nissl staining and Acid fuchsin, show that acetylsalicylic acid and acetaminophen are able to protect hippocampal neurons against quinolinic acidinduced necrotic cell death. Immunohistochemical investigations show that QA induces apoptotic cell death in the hippocampus, which is inhibited by ASA and acetaminophen. In addition, ASA and acetaminophen inhibited MPP+ induced apoptotic cell death in the rat striatum. The study also sought to elucidate possible mechanisms by which ASA and acetaminophen exert neuroprotective effects in the presence of MPP+ as these agents are shown to prevent the MPP+-induced reduction in dopamine levels. The results show that acetylsalicylic acid and acetaminophen inhibit the action of this neurotoxin on the mitochondrial electron transport chain, a common source of free radicals in the cell. In addition, these agents were shown to block the neurotoxic effects of MPP+ on the enzymatic defence system of the brain i.e. superoxide dismutase, glutathione peroxidase and catalase. The reduction in glutathione levels induced by MPP+ is significantly inhibited by acetylsalicylic acid and acetaminophen. The results imply that these agents are capable of not only scavenging free radicals but also enhance the cell defence mechanism against toxicity in the presence of MPP+. These agents also block the MPP+-induced inhibition of dopamine uptake into the cell. This would therefore reduce auto-oxidation of dopamine thus implying another mechanism by which these agents exert a neuroprotective role in MPP+-induced neurotoxicity. The discovery of neuroprotective properties of acetylsalicylic acid and acetaminophen is important considering the high usage of these agents and the increased incidence in neurological disorders. The findings of this thesis point to the need for clinical studies to be conducted as the results show acetylsalicylic acid and acetaminophen to have a definite role to play as antioxidants. This study therefore provides novel information regarding the neuroprotective effects of these agents and favours the use of these agents in the treatment of neurodegenerative disorders, such as AD and PD, in which oxidative stress is implicated.

This qualitative case study investigated the impact of sand tray on individuals diagnosed with Alzheimer’s and other forms of dementia. Four participants successfully completed the creation of sand trays while the researcher observed, interviewed, and documented the individual sand trays. The intervention established that sand tray allows the dementia patient to kinesthetically connect to their inner cognitions through the intentional symbolic expression offered by this unique therapeutic medium. Using a series of eight sand trays of varying thematic concepts, the participants were offered a modality to facilitate a synthesization of their continued individuation, presenting a possible neural pathway to connect and express thoughts, feelings, emotions, concerns, challenges, and fears. The findings of this study include the fact that all trays were classified as “empty” and that the majority of the participants placed objects almost exclusively on the right side of the tray, which is commonly associated with the concreteor conscious side. The use of sand tray allowed each individual the opportunity to create autobiographies in the sand and literally navigate through time – past, present, and future, confronting fears, expressing hope and possibilities. The results of the research study offer insight into the psychotherapeutic effects of using sand tray with dementia patients, as well as a better understanding of the cognitive and expressive abilities and limitations of an individual with impaired memory. The results also offer insight into the difficulties with short-term memory in this population and possibly indicate a potential means for monitoring cognitive decline. Keywords: Neurocognitive disorder, Alzheimer’s, dementia, sand tray, play therapy / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2013.

Hung Shieh-Jung Fanny. / Thesis submitted in: August 2002. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 97-109). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Content --- p.vi / List of Abbreviations --- p.xiii / List of Figure --- p.xv / List of Tables --- p.xix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Alzheimer's Disease (AD) --- p.1 / Chapter 1.1.1 --- Clinical features --- p.2 / Chapter 1.2 --- Histopathological studies of AD --- p.2 / Chapter 1.2.1 --- Neuritic plaques --- p.2 / Chapter 1.2.2 --- Neurofibrillary tangles (NFT) --- p.4 / Chapter 1.2.3 --- Tau --- p.5 / Chapter 1.3 --- Kinases and Alzheimer's Disease --- p.7 / Chapter 1.4 --- Free radical damage --- p.8 / Chapter 1.5 --- Available treatment for AD --- p.7 / Chapter 1.6 --- A Chinese medicinal material 一 Danshen （（Salviae miltiorrhizcie) --- p.11 / Chapter 1.6.1 --- Chemical constituents --- p.11 / Chapter 1.6.1.1 --- Lipophilic Compounds of Danshen --- p.12 / Chapter 1.6.1.2 --- Water-soluble Compounds of Danshen --- p.17 / Chapter 1.6.2 --- Pharmacological usage --- p.20 / Chapter 1.6.2.1 --- Action on Coronary system --- p.20 / Chapter 1.6.2.2 --- Bacteriostatic action --- p.21 / Chapter 1.6.2.3 --- Actions on the immune system --- p.21 / Chapter 1.6.3 --- Biological activity on brain --- p.22 / Chapter 1.7 --- Objectives and scope of the project --- p.23 / Chapter Chapter 2 --- General Materials and Method --- p.24 / Chapter 2.1 --- Recombinant DNA techniques --- p.24 / Chapter 2.1.1 --- Preparation of E. coli strain DH-5a competent cells --- p.24 / Chapter 2.1.2 --- Transformation of plasmid DNA into competent cells --- p.25 / Chapter 2.1.3 --- Preparation of plasmid DNA using QIAGEN Plasmid Maxipreps kit --- p.25 / Chapter 2.1.4 --- Phenol/ choroform extraction of DNA --- p.26 / Chapter 2.1.5 --- Spectrophotometric quantitation of the amount and purity of DNA --- p.27 / Chapter 2.2 --- Drugs preparation --- p.27 / Chapter 2.2.1 --- Preparation of aqueous extracts of Traditional Chinese Medicine (TCM) --- p.27 / Chapter 2.2.2 --- Preparation of ethanol extracts of Traditional Chinese Medicine (TCM) --- p.27 / Chapter 2.3 --- "3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium (MTT) assay " --- p.28 / Chapter 2.4 --- Analysis of proteins from culture cells --- p.28 / Chapter 2.4.1 --- Extraction of total proteins from culture cells --- p.28 / Chapter 2.4.2 --- Quantitation of protein by Bradford method --- p.29 / Chapter 2.4.3 --- Protein separation by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.29 / Chapter 2.4.4 --- Western blot analysis --- p.31 / Chapter 2.5 --- Reagents and buffers --- p.32 / Chapter 2.5.1 --- Reagents for competent cell preparation --- p.32 / Chapter 2.5.2 --- Reagents provided by QIAGEN Plasmid Maxipreps kit --- p.33 / Chapter 2.5.3 --- Reagents for SDS-PAGE --- p.34 / Chapter 2.5.4 --- Reagents and buffers for Western Blotting --- p.35 / Chapter 2.5.5 --- Cell lines --- p.36 / Chapter 2.5.6 --- Antibodies --- p.37 / Chapter 2.5.7 --- Plasmids --- p.37 / Chapter 2.5.8 --- Other Chemicals --- p.38 / Chapter Chapter 3 --- The effect of Danshen on GSK-3 induced hyperposphorylation of tau in Cos7 cells / Chapter 3.1 --- Introduction --- p.39 / Chapter 3.1.1 --- Glycogen synthase kinase-3 (GSK-3) --- p.39 / Chapter 3.1.2 --- Structure of GSK-3 --- p.39 / Chapter 3.1.3 --- The importance of GSK-3 in AD --- p.39 / Chapter 3.2 --- Materials and Methods --- p.41 / Chapter 3.2.1 --- Transfection of Gsk-3 and tau into Cos7 monkey kidney cells --- p.43 / Chapter 3.2.2 --- Extraction of total proteins from culture cells --- p.44 / Chapter 3.2.3 --- Quantitation of protein by Bradford method --- p.44 / Chapter 3.2.4 --- Protein separation by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.44 / Chapter 3.2.5 --- Western blot analysis --- p.44 / Chapter 3.3 --- Results --- p.45 / Chapter 3.3.1 --- Toxicity test on Cos7 cells --- p.45 / Chapter 3.3.2 --- The effect of ethanol extract of Danshen on GSK-3 β induced tau phosphorylation --- p.45 / Chapter 3.3.3 --- The effect of aqueous extract of Danshen on GSK-3 β induced tau phosphorylation --- p.48 / Chapter 3.3.4 --- The effect of Protocatechualdehyde on GSK-3β induced tau phosphorylation --- p.48 / Chapter 3.3.5 --- The effect of Salvianolic acid B on GSK-3β induced tau phosphorylation --- p.49 / Chapter 3.4 --- Discussion --- p.60 / Chapter Chapter 4 --- Cdk5 induced hyperposphorylation of tau in CHO cells / Chapter 4.1 --- Introduction --- p.63 / Chapter 4.1.1 --- Cyclin dependent kinase 5 (Cdk5) --- p.63 / Chapter 4.1.2 --- Structure of Cdk5 --- p.63 / Chapter 4.1.3 --- Neurological functions of Cdk5 --- p.64 / Chapter 4.2 --- Materials and Methods --- p.66 / Chapter 4.2.1 --- Transfection of p35 and tau into CHO cells --- p.66 / Chapter 4.2.2 --- Extraction of total proteins from culture cells --- p.67 / Chapter 4.2.3 --- Quantitation of protein by Bradford method --- p.67 / Chapter 4.2.4 --- Protein separation by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.67 / Chapter 4.2.5 --- Western blot analysis --- p.67 / Chapter 4.3 --- Results --- p.68 / Chapter 4.3.1 --- Toxicity test on CHO cells --- p.68 / Chapter 4.3.2 --- Tau transfection in Cdk5/p35 and TauON3R transiently transfected in CHO cells --- p.68 / Chapter 4.3.3 --- Effect of roscovitine treatment on the transiently tau and p35 transfection in CHO cells --- p.74 / Chapter 4.3.4 --- "Effects of aqueous active components of Danshen, PCAH and SAB on the transiently tau and p35 transfection in CHO cells " --- p.74 / Chapter 4.4 --- Discussion --- p.79 / Chapter Chapter 5 --- Antioxidant effect of Danshen and its active components on lipid peroxidation / Chapter 5.1 --- Introduction --- p.81 / Chapter 5.1.1 --- Red-blood-cell hemolysis model --- p.82 / Chapter 5.2 --- Materials and methods --- p.84 / Chapter 5.2.1 --- Red-blood-cell hemolysis model --- p.84 / Chapter 5.2.2 --- Materials --- p.85 / Chapter 5.2.2.1 --- Animals --- p.85 / Chapter 5.2.2.2 --- Chemicals --- p.85 / Chapter 5.3 --- Results --- p.86 / Chapter 5.3.1 --- Aqueous and ethanol extracts of Danshen --- p.86 / Chapter 5.3.2 --- Active components ´ؤ Protocatechualdehyde and Salvianolic acid B --- p.87 / Chapter 5.4 --- Discussion --- p.91 / Chapter Chapter 6 --- General discussion and Outlook / Chapter 6.1 --- General discussion --- p.93 / Chapter 6.2 --- Proposed study in the future --- p.95 / Chapter 6.2.1 --- In vitro kinase assay using gamma32 P ATP and substrate with or without TCM --- p.95 / Chapter 6.2.2 --- Use of neuroblastoma cells (SHSY-5Y) to study the effect of Danshen and its active components on tau phosphorylation --- p.95 / Chapter 6.2.3 --- Thiobarbituric acid-reacting substances (TBARS) assay --- p.96 / Chapter 6.2.4 --- In vitro phosphatase kinase assay --- p.96

by Tsz-Wan Ho. / Thesis submitted in: July 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 107-122). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Content --- p.vi / Abbreviations --- p.x / List of Figures --- p.xi / List of tables --- p.xiv / Chapter CHAPTER 1 --- GENERAL INTRODUCTION --- p.1 / Chapter 1.1 --- Alzheimer'sDisease --- p.1 / Chapter 1.2 --- Hallmarks of AD --- p.3 / Chapter 1.2.1 --- The amyloid cascade hypothesis --- p.3 / Chapter 1.2.2 --- The tauopathy hypothesis --- p.4 / Chapter 1.3 --- The Cholinergic Hypothesis --- p.6 / Chapter 1.3.1 --- Cholinergic drug therapy --- p.7 / Chapter 1.3.2 --- Acetylcholinesterase inhibitors --- p.8 / Chapter 1.3.2.1 --- Tacrine --- p.10 / Chapter 1.3.2.2 --- Donepezil --- p.10 / Chapter 1.3.2.3 --- Rivastigimine - ENA-713 --- p.11 / Chapter 1.4 --- AChE inhibitors from plants --- p.12 / Chapter 1.4.1 --- Galanthamine --- p.12 / Chapter 1.4.2 --- Huperzine --- p.14 / Chapter 1.4.3 --- α-onocerin --- p.15 / Chapter 1.4.4 --- (+)-alpha-viniferin --- p.16 / Chapter 1.5 --- My project --- p.17 / Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.18 / Chapter 2.1 --- Preparation of CMM --- p.18 / Chapter 2.2.1 --- Selecting criteria and sources --- p.18 / Chapter 2.2.2 --- Preparation of aqueous extract --- p.18 / Chapter 2.2.3 --- Preparation of ethanol extract --- p.18 / Chapter 2.3 --- Routine maintenance of cell lines --- p.19 / Chapter 2.4 --- Toxicity test --- p.19 / Chapter 2.5 --- Ellman assay --- p.20 / Chapter 2.6 --- Ellman assay over BuChE --- p.21 / Chapter 2.7 --- Drugs --- p.21 / Chapter CHAPTER 3 --- SCREENING OF ACETYLCHOLINESTERASE INHIBITORS FROM CHINESE MEDICINAL MATERIALS --- p.23 / Chapter 3.1 --- Introduction --- p.23 / Chapter 3.2 --- Materials and Methods --- p.23 / Chapter 3.3 --- Results and discussion --- p.24 / Chapter 3.3.1 --- Preliminary screening of 45 selected TCMs for AChE inhibition --- p.24 / Chapter 3.3.2 --- Rescreening of drugs that show AChE inhibition in both aqueous and organic extracts --- p.25 / Chapter 3.4 --- Discussion --- p.28 / Chapter CHAPTER 4 --- CHARACTERIZATION OF ANTI-ACETYLCHOLINESTERASE ACTIVITY FROM SALVIA MBLTIORRHIZA BGE.(丹參) --- p.33 / Chapter 4.1 --- Introduction --- p.33 / Chapter 4.1.1 --- Clinical application of Danshen --- p.34 / Chapter 4.1.2 --- Pharmacological properties of Danshen and Salvia species --- p.34 / Chapter 4.1.2.1. --- Antiinflammatory and antibacterial responses --- p.35 / Chapter 4.1.2.2 --- Diabetes --- p.35 / Chapter 4.1.2.3 --- Alcoholism --- p.35 / Chapter 4.1.2.4 --- Apoptosis --- p.36 / Chapter 4.1.2.5 --- The effect of Salvia extracts on neuro-receptors --- p.36 / Chapter 4.1.3 --- Anti-cholinesterase activity by the Salvia species --- p.37 / Chapter 4.1.4 --- Active components from Salvia miltiorrhiza Bge --- p.38 / Chapter 4.2 --- Effects of tanshinone derivatives on AChE --- p.39 / Chapter 4.2.1 --- Materials and Methods --- p.39 / Chapter 4.2.2. --- Results --- p.39 / Chapter 4.3 --- Discussion --- p.50 / Chapter CHAPTER 5 --- EXTRACTION OF CRYPTOTANSHINONE FROM SALVIA MILTIORRHIZA --- p.54 / Chapter 5.1 --- Introduction --- p.54 / Chapter 5.1.1 --- Reverse phase high performance liquid chromatography (RP-HPLC) --- p.55 / Chapter 5.2 --- Materials and Methods --- p.56 / Chapter 5.2.1 --- Extracts of Danshen from different sources for obtaining the chemical profile --- p.55 / Chapter 5.2.2 --- Reverse phase high performance liquid chromatography (RP-HPLC) --- p.57 / Chapter 5.2.2.1 --- Analytical RP-HPLC --- p.57 / Chapter 5.2.2.2 --- Preparative RP-HPLC --- p.58 / Chapter 5.3 --- Results --- p.60 / Chapter 5.3.1 --- Identification of Peaks that contain the proposed active components --- p.60 / Chapter 5.3.2 --- Different samples of Danshen contain different amount of active components that can exert inhibitory effect on hAChE --- p.66 / Chapter 5.4 --- Discussion --- p.75 / Chapter CHAPTER 6 --- EFFECT OF CRYPTOTANSHINONE ON CALCIUM MOVEMENT in SH-SY5Y Cell --- p.80 / Chapter 6.1 --- Introduction --- p.80 / Chapter 6.2 --- Materials and Methods --- p.82 / Chapter 6.2.1 --- Reagents and drugs --- p.82 / Chapter 6.2.2 --- Calcium fluorimetry --- p.82 / Chapter 6.3 --- Results --- p.85 / Chapter 6.4 --- Discussion --- p.96 / Chapter CHAPTER 7 --- GENERAL DISCUSSION --- p.98 / Chapter 7.1 --- Structure-function relationship of crytotanshinone and dihydrotanshinone I --- p.98 / Chapter 7.2 --- Further study on cryptotanshinone and dihydrotanshinone I --- p.100 / Chapter 7.2.1 --- Modulation on nictonic receptor --- p.100 / Chapter 7.2.2 --- Behavioral study on mice --- p.101 / Chapter 7.2.3 --- Large scale production of the desired active components --- p.102 / Chapter 7.3 --- Study on other candidate herbs --- p.102 / References --- p.107

Alzheimer's disease (AD) is associated with decreased brain energy metabolism. Hypometabolism in the posterior cingulate cortex (PCC) occurs before the onset of memory deficits in subjects at genetic risk for AD who are not yet cognitively impaired. There is a specific inhibition in cytochrome oxidase (C.O.) in the PCC, an area involved in spatial navigation. Creating an animal model that exhibits the early pathophysiology of AD is important for developing and testing drugs that could reverse memory problems associated with such deficits. Methylene blue (MB) is a compound that improves C.O. activity and memory retention in rats. This dissertation had three specific aims: 1) to examine if isolated PCC hypometabolism causes spatial memory deficits in rats; 2) to find a dose of MB that improves memory without nonspecific behavioral effects; and 3) to prevent memory deficits from PCC hypometabolism with low dose MB. PCC hypometabolism was produced by focal administration of sodium azide, an inhibitor of C.O. activity. PCC hypometabolism resulted in impaired spatial memory in a hole board food-search task, increased oxidative damage, and neurotoxicity in the PCC. In addition, PCC hypometabolism resulted in reduced inter-regional correlations in brain activity. Our second set of studies examined the dose-response effects of MB. Our findings demonstrated that a low dose of MB: 1) enhanced memory in open field habituation and object recognition tasks; 2) did not affect general locomotor activity, exploration, motivation, or anxiety; and 3) increased brain oxygen consumption 24 hr after in vivo administration. Finally, our last study found that low dose MB prevented the deficits caused by PCC hypometabolism. MB did not prevent PCC inhibition or cell loss caused by sodium azide. Inter-regional correlations of brain metabolic activity suggested that rats treated with MB were using a different, but equally efficient, strategy for memory retrieval. This animal model of C.O. hypometabolism in the PCC can provide information to understand the mechanisms that regulate early pathological degeneration and reveal new therapeutic strategies aimed at reducing or preventing cognitive decline. Studies of low dose MB in humans are needed to examine its effects in AD patients.

In 2015, an estimated 46.8 million people were living with dementia, a number predicted to increase to 74.7 million by 2030 and 131.5 million by 2050. Whilst there are numerous causes for the development of dementia, Alzheimer's disease is by far the most common, accounting for approximately 50-70% of all cases. Current therapeutic agents against Alzheimer's disease are palliative in nature, managing symptoms without addressing the underlying cause and thus disease progression and patient death remain a certainty. Whilst the main underlying cause for the development of Alzheimer's disease was originally thought to be an abnormal deposition of insoluble amyloid-β peptide derived plaques within the brain, the failure of several high-profile therapeutic agents, which were shown to reduce the plaque burden without improving cognition, has recently prompted a shift in focus to soluble oligomeric forms of amyloid-β peptide. Such soluble oligomers have been shown to be toxic in their own right and to precede plaque deposition. Soluble amyloid-β oligomers have been identified in various subcellular compartments, including the mitochondria, where they form a complex with the 17β-HSD10 enzyme resulting in cytotoxicity. Interestingly, hallmarks of this toxicity have been shown to be dependent on the catalytic activity of the 17β-HSD10 enzyme, suggesting two therapeutic approaches may hold merit in treating Alzheimer's disease: disrupting the interaction between the 17β-HSD10 enzyme and amyloid-β peptide, or directly inhibiting the catalytic activity of the 17β-HSD10 enzyme. In 2006, Frentizole was identified as a small molecule capable of disrupting the 17β-HSD10/amyloid interaction. The work described herein details the generation of a robust screening assay allowing the catalytic activity of the 17β-HSD10 enzyme to be measured in vitro. This assay was subsequently employed for small molecule screening using two methodologies; first in a targeted approach using compounds derived from the Frentizole core scaffold, and second in an explorative manner using a diverse library of compounds supplied by the National Cancer Institute. As a result, a range of novel small molecule inhibitors of the 17β-HSD10 enzyme have been identified and the most promising characterised in terms of potency and mechanism of action. De-selection assays were developed to allow the efficient triage of hit compounds and work was begun on a cellular based assay which would allow the ability of compounds of interest to reverse a disease relevant phenotype to be assessed in a cellular environment. As such, we now have a number of hit compounds which will form the basis for the generation of subsequent series of derivatives with improved potency and specificity, as well as the robust assays required to measure such criteria, potentially leading to the generation of novel therapeutic agents against Alzheimer's disease.

Alzheimer’s Disease (AD) is a progressive neurodegenerative disease that accounts for 60-70% of the 55 million worldwide dementia cases. The blood-brain barrier (BBB) acts as a mediator between the brain and cerebral vasculature, preventing the passage of deleterious substances, albeit significantly reducing drug delivery efficiency to the brain. The BBB is comprised of specialized cells that both maintain brain homeostasis and respond to pathological stress. Focused ultrasound-induced blood-brain barrier opening (FUS-BBBO) presents a noninvasive, transient, and targeted method to enhance drug delivery by locally increasing BBB permeability, in addition to modulating the neuroimmune landscape. This technique offers countless therapeutic opportunities for diseases of the brain, especially neurodegenerative disorders and AD. Previous studies have demonstrated effective pathological amelioration and cognitive improvement by applying FUS-BBBO in severely progressed murine models of AD. However, growing interest in clinical translation of FUS-BBBO and in alternative, early intervention therapeutic paradigms necessitates a more thorough characterization of the role of FUS-BBBO in AD therapeutics, particularly at early disease states. This thesis focuses on characterizing three key elements of FUS-BBBO treatment for applications to AD therapy. First, the physical effects of age and AD on the brain’s response to a single session of FUS-BBBO will be characterized. Next, the extent of cognitive and pathological improvement resulting from early intervention in male and female AD mice with repeated FUS-BBBO alone, then in combination with an amyloid-targeting therapeutic will be evaluated. Finally, the cell-specific response of astrocytes, oligodendrocytes, neurons and endothelial cells to FUS-BBBO will be characterized to elucidate the contribution of these cell types to previously observed cognitive and pathological improvements in male and female, young and aged, wild-type and AD mice. Broadly, the findings of the work described herein will elucidate the role of FUS-BBBO in AD therapeutics. By defining the most important considerations for applying FUS-BBBO in aged and AD populations, characterizing the expected cognitive and pathological outcomes from early FUS-BBBO intervention, and characterizing a time course of cell-specific responses to elucidate the mechanisms that underlie these observations, these aims collectively seek to improve our understanding and optimize our use of FUS-BBBO for AD therapeutics.