IN SILICO IDENTIFICATION OF APOBEC3B SMALL MOLECULE INHIBITORS FROM DTP-NCI LIBRARIES

Objective: APOBEC3B (A3B) enzyme causes C-to-T or C-to-G somatic alteration in the cancer genome, leading to the evolution of a broad spectrum of human cancers. The present study aims to identify A3B small molecule inhibitors using a top-down approach via pharmacoinformatic virtual screening. Methods: Virtual screening of 2951 drug-alike molecules with diversified structures from the National Cancer Institute Development Therapeutics Program (DTP-NCI) compounds library was performed using GOLD and AutoDock Vina docking programs against the 3D structure of A3B (PDB ID: 5TD5). Results: Amongst the docked compounds, Nordracorubin, NSC641233 and Raloxifene hydrochloride showed the most potent binding affinities towards A3B on both Autodock/Vina and GOLD. Several significant similarities were observed between A3B and the three hits, including hydrogen bonds and pi-pi stacking. The three compounds also exhibited interaction with the centralized zinc cofactor and amino acid residues that directly contribute the deaminase activity of A3B enzyme. Conclusion: We hypothesize that the findings from this study could significantly shorten the quest for novel molecules against the A3B after confirmation with subsequent in vitro and in vivo studies in the near future

Ethanol extract of Centella asiatica improved methamphetamine-induced neurotoxicity on mouse model via stimulating superoxide dismutase II and microRNA-34A expression

Neurotoxicity induced by a psychostimulant drug, methamphetamine (METH) is associated with devastating and persistent neurotoxicity effects on the central nervous system (CNS). Centella asiatica (CA) is known as an antioxidant and neuroprotective agent. However, there is a limited study on natural-derived therapeutic to attenuate neurotoxicity induced by METH. We aimed to investigate the effects of METH and ethanol extract CA (CAE) on motor performance of animal model and the expression of manganese superoxide dismutase II (SOD2) and microRNA-34a (miR-34a) in the brain tissue. Male Sprague-Dawley rats were administered with METH (50 mg/kg per body weight) twice per day for 4 days, CAE (300 mg/kg & 500 mg/kg per body weight for 21 days and combination of METH and CAE for 21 day(s). Weight of rat was measured and motor performance was evaluated using vertical pole and narrow beam tests. Expression of SOD2 and miR-34a were measured using Quantitative Real-time Polymerase Chain Reaction (RT-qPCR). Group III (300 mg/kg CAE); p<0.001, Group IV (500 mg/kg CAE); p<0.001, Group V (METH+300 mg/kg CAE); p<0.01 and Group VI (METH+500 mg/kg CAE); p<0.01 significantly improved latency in the vertical pole test compared to METH group. Meanwhile, Group III (300 mg/kg CAE); p<0.001 and Group IV (500 mg/kg CAE); p<0.001 significantly decreased latency in the narrow beam test compared to METH. Post-treatment of CAE on METH-treated rats, Group V (METH+300 mg/kg CAE) and Group VI (METH+500 mg/kg CAE) nonsignificantly upregulated the SOD2 expression by 3.78±1.03 and 4.05±0.19 folds compared to METH, respectively. Post-treatment of CAE on METH-treated rats, Group V (METH+300 mg/kg CAE) and Group VI (METH+500 mg/kg CAE) non-significantly upregulated the miR-34a expression by (7.02±3.73) and (6.75±1.94) folds compared to METH, respectively. CAE could be suggested as a promising natural-derived therapeutic for METH-induced neurotoxicity to ameliorating motor performance and triggering SOD2 and miR-34a expression

Data on the construction of a recombinant HEK293 cell line overexpressing hERG potassium channel and examining the presence of hERG mRNA and protein expression

The data presented in this article are related to the research article entitled “The effects of deoxyelephantopin on the cardiac delayed rectifier potassium channel current (IKr) and human ether-a-go-go-related gene (hERG) expression” (Y.F. Teah, M.A. Abduraman, A. Amanah, M.I. Adenan, S.F. Sulaiman, M.L. Tan) [1], which the possible hERG blocking properties of deoxyelephantopin were investigated. This article describes the construction of human embryonic kidney 293 (HEK293) cells overexpressing HERG potassium channel and verification of the presence of hERG mRNA and protein expression in this recombinant cell line

Isolation, identification and bioassay of flavonoids from Bouea macrophylla Griff

Bouea macrophylla Griff., a species belonging to the Anacardiaceae family is a flowering plant native to Southeast Asia and also known as kundang, kundang daun besar, and setar in Malaysia. The fruit can be eaten raw or as a pickle, while the young leaves can be consumed as salads. It has been claimed to be able to accelerate wound healing, prevent cancer, reduce the risk of stroke, and enhance blood circulation. The previous study on the plant from the same genus, known as B. oppositofolia has shown the presence of various flavonoids. The present study was designed to isolate and elucidate flavonoids from this plant. The twig extract of kundang was purified by using several chromatographic techniques including Vacuum Liquid Chromatography (VLC), Column Chromatography (CC), and preparative-Thin Layer Chromatography (pTLC). The structures of isolated compounds were characterized by using spectroscopic methods including Nuclear Magnetic Resonance (NMR), infrared (IR), and ultraviolet (UV) spectral data, as well as comparison with the data reported in the literature. Five flavonoids were isolated and purified from the twigs of B. macrophylla which includes one flavanonol known as garbanzol; one flavonol which is resokaempferol; one flavandiol characterized as catechin; and two flavandiol known as mollisacacidin and guibourtacacidin. The results of the glucose uptake experiment indicated that the extract and compounds tested affected the glucose uptake rate of the insulin-resistant C2C12 cell line as compared to the standard. This is the first report describing the elucidation of the stated compounds from B. macrophylla as well as its glucose uptake study

Isolation, identification and bioassay of flavonoids from Bouea macrophylla Griff

Bouea macrophylla Griff., a species belonging to the Anacardiaceae family is a flowering plant native to Southeast Asia and also known as kundang, kundang daun besar, and setar in Malaysia. The fruit can be eaten raw or as a pickle, while the young leaves can be consumed as salads. It has been claimed to be able to accelerate wound healing, prevent cancer, reduce the risk of stroke, and enhance blood circulation. The previous study on the plant from the same genus, known as B. oppositofolia has shown the presence of various flavonoids. The present study was designed to isolate and elucidate flavonoids from this plant. The twig extract of kundang was purified by using several chromatographic techniques including Vacuum Liquid Chromatography (VLC), Column Chromatography (CC), and preparative-Thin Layer Chromatography (pTLC). The structures of isolated compounds were characterized by using spectroscopic methods including Nuclear Magnetic Resonance (NMR), infrared (IR), and ultraviolet (UV) spectral data, as well as comparison with the data reported in the literature. Five flavonoids were isolated and purified from the twigs of B. macrophylla which includes one flavanonol known as garbanzol; one flavonol which is resokaempferol; one flavandiol characterized as catechin; and two flavandiol known as mollisacacidin and guibourtacacidin. The results of the glucose uptake experiment indicated that the extract and compounds tested affected the glucose uptake rate of the insulin-resistant C2C12 cell line as compared to the standard. This is the first report describing the elucidation of the stated compounds from B. macrophylla as well as its glucose uptake study

In vivo toxicity study of Erythroxylum cuneatum leaves extract and its effects on working memory of rats

Erythroxylum cuneatum has been traditionally proven to possess beneficial properties in treating drug addiction and other illness. Due to less information on this plant, this elusive plant was investigated further to evaluate the in vivo toxicity profile of the plant and to investigate the effect of E. cuneatum on cognitive performance in rats. Two different extracts were produced from the leaves of E. cuneatum which were aqueous and alkaloid extracts. Acute in vivo toxicity test was evaluated in ICR mice to determine their medium lethal dose 50 value. In the in-vivo toxicity study, aqueous extract showed the almost similar toxic effect as alkaloid extract which was 416.86 mg/kg for alkaloid extract and 316.23 mg/kg for aqueous extract. These findings suggesting that aqueous and alkaloid extracts showed toxic effects at the high dose, thus safe at a low dose. Working memory task using novel object discrimination test (NOD) was performed for the determination of neurobehavioral profiles. In the NOD test, alkaloid-treated rats did not show any significant discrimination between the familiar and novel object (P > 0.05); thus it can be interpreted as not induce a memory defi cit. It can also be postulated that the extract has no effect on memory and learning neither improvises nor impairs the cognitive function. In conclusion, since E. cuneatum does not show any impairment on cognitive, its pharmacological properties could be further investigated without significant changes in cognitive performance

Centella asiatica prevents chronic unpredictable mild stress-induced behavioral changes in rats

Background: Depression is a psychological disorder which is associated with mood swings and cognitive deficits, and is ranked third among the leading causes of global health care burden. Chronic unpredictable mild stress (CUMS) has been shown to induce depression-like behaviors in rodents, which exhibit similarities to the human form of depression. Centella asiatica (CA) is an ancient medicinal plant which has neuro protective potential. This work aimed to assess the pro-tective role of CA on CUMS-induced rats. Methods: Thirty six rats randomly divided into six groups were used for the evaluation. The groups were as follows: 1, Unstressed + normal saline (control);2, CUMS + normal saline (model); 3, CUMS + fluoxetine (10 mg/kg) standard antidepressant; 4-6,CUMS + CA (200, 400 & 800 mg/kg). Nine different stressors (S) (S1: 24-h food deprivation, S2: 24-h water deprivation, S3: 5-min cold swimming (at 5◦C), S4: 12-h change of cage mate, S5: 1-mintail pinch (1 cm from the tip of the tail), S6: 12-h cage tilt (at 45◦), S7: 12-h overcrowding of cage,S8: 12-h wet bedding with 200 mL of water, and S9: 4-h physical restraint) were administered to the stressed groups with at least 2 stressors per day. The treatments lasted for 8 weeks, and the rats were evaluated through open field test (OFT) and elevated plus maze (EPM) for anxiety-like behavior, forced swimming test (FST) for depression-like behaviour, and T-maze spontaneous alter-nation for learning and memory. Furthermore, serum cortisol levels were also evaluated. Results: CUMS-induced rats showed anxiety-like behaviors in OFT and EPM tests, depression-like behavior in FST and cognitive deficits in T-maze test, as well as increased serum cortisol levels. Conversely, administration of CA (at 400 and 800 mg/kg doses) and fluoxetine (at 10 mg/kg dose) prevented the aberrant behavioral changes and also the changes in the serum cortisol levels. No significant differences of behaviors were observed between the groups of rats administered with CA (400 and800 mg/kg) and those administered with fluoxetine (10 mg/kg), suggesting that the therapeutic potential of CA is comparable to that of fluoxetine. Conclusion: The data obtained showed that CA, at doses of 400 and 800 mg/kg, effectively reversed the anxiety and depression-like behaviors, amnesic behaviors, as well as serum cortisol levels in a CUMS-induced rat model of depression. This suggests that CA is a potential candidate for the development of future anti-depressants

Centella asiatica protects d-Galactose/AlCl3 mediated alzheimers disease-like rats via PP2A/GSK-3β signaling pathway in their hippocampus

Alzheimer's disease (AD) is a progressive neurodegenerative disorder more prevalent among the elderly population. AD is characterised clinically by a progressive decline in cognitive functions and pathologically by the presence of neurofibrillary tangles (NFTs), deposition of beta-amyloid (Aβ) plaque and synaptic dysfunction in the brain. Centella asiatica (CA) is a valuable herb being used widely in African, Ayurvedic, and Chinese traditional medicine to reverse cognitive impairment and to enhance cognitive functions. This study aimed to evaluate the effectiveness of CA in preventing d-galactose/aluminium chloride (d-gal/AlCl3) induced AD-like pathologies and the underlying mechanisms of action were further investigated for the first time. Results showed that co-administration of CA to d-gal/AlCl3 induced AD-like rat models significantly increased the levels of protein phosphatase 2 (PP2A) and decreased the levels of glycogen synthase kinase-3 beta (GSK-3β). It was further observed that, CA increased the expression of mRNA of Bcl-2, while there was minimal effect on the expression of caspase 3 mRNA. The results also showed that, CA prevented morphological aberrations in the connus ammonis 3 (CA 3) sub-region of the rat's hippocampus. The results clearly demonstrated for the first time that CA could alleviate d-gal/AlCl3 induced AD-like pathologies in rats via inhibition of hyperphosphorylated tau (P-tau) bio-synthetic proteins, anti-apoptosis and maintenance of cytoarchitecture

Hypoxia-induced neuroinflammation in Alzheimer’s disease: potential neuroprotective effects of Centella asiatica

Alzheimer’s disease (AD) is a neurodegenerative disorder that is characterised by the presence of extracellular beta-amyloid fibrillary plaques and intraneuronal neurofibrillary tau tangles in the brain. Recurring failures of drug candidates targeting these pathways have prompted research in AD multifactorial pathogenesis, including the role of neuroinflammation. Triggered by various factors, such as hypoxia, neuroinflammation is strongly linked to AD susceptibility and/or progression to dementia. Chronic hypoxia induces neuroinflammation by activating microglia, the resident immune cells in the brain, along with an increased in reactive oxygen species and pro-inflammatory cytokines, features that are common to many degenerative central nervous system (CNS) disorders. Hence, interests are emerging on therapeutic agents and plant derivatives for AD that target the hypoxia-neuroinflammation pathway. Centella asiatica is one of the natural products reported to show neuroprotective effects in various models of CNS diseases. Here, we review the complex hypoxia-induced neuroinflammation in the pathogenesis of AD and the potential application of Centella asiatica as a therapeutic agent in AD or dementia