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Alzheimer’s disease (AD) is the most common form of dementia, which is progressively affecting elderly people. The dyshomeostasis of biometals and accumulation of toxic metals are usually observed in numerous neurodegenerative diseases including AD. In the central nervous system, metal imbalance–caused neurotoxic activities are usually linked with decreased enzymatic activities, increased aggregation of proteins, and oxidative stress, where a series of processes can result in neurodegeneration and cell death. Even though the relations between neurodegenerative diseases and biometal imbalance are still elusive, there is a growing interest in a group of major endogenous proteins that are associated with the transports of metals. Aberrant expression of these endogenous proteins is associated with the biometal imbalance and AD pathogenesis. Indeed, heavy metals are extremely toxic to the nervous system. Various studies have demonstrated that the toxic effects of heavy metals can result in amyloid beta (Aβ) aggregation, neurofibrillary tangles, and even loss of neurons. In this article, we have focused on the molecular processes through which exposure to biometals and toxic metals can play roles in AD pathogenesis.

Alzheimer's disease (AD) is the most common form of dementia, which is progressively affecting elderly people. The dyshomeostasis of biometals and accumulation of toxic metals are usually observed in numerous neurodegenerative diseases including AD. In the central nervous system, metal imbalance-caused neurotoxic activities are usually linked with decreased enzymatic activities, increased aggregation of proteins, and oxidative stress, where a series of processes can result in neurodegeneration and cell death. Even though the relations between neurodegenerative diseases and biometal imbalance are still elusive, there is a growing interest in a group of major endogenous proteins that are associated with the transports of metals. Aberrant expression of these endogenous proteins is associated with the biometal imbalance and AD pathogenesis. Indeed, heavy metals are extremely toxic to the nervous system. Various studies have demonstrated that the toxic effects of heavy metals can result in amyloid beta (Aβ) aggregation, neurofibrillary tangles, and even loss of neurons. In this article, we have focused on the molecular processes through which exposure to biometals and toxic metals can play roles in AD pathogenesis.

Alzheimer's disease (AD) is a progressive neurodegenerative disease that causes chronic cognitive dysfunction. Most of the AD cases are late onset, and the apolipoprotein E (APOE) isoform is a key genetic risk factor. The APOE gene has 3 key alleles in humans including APOE2, APOE3, and APOE4. Among them, APOE4 is the most potent genetic risk factor for late-onset AD (LOAD), while APOE2 has a defensive effect. Research data suggest that APOE4 leads to the pathogenesis of AD through various processes such as accelerated beta-amyloid aggregations that raised neurofibrillary tangle formation, cerebrovascular diseases, aggravated neuroinflammation, and synaptic loss. However, the precise mode of actions regarding in what way APOE4 leads to AD pathology remains unclear. Since APOE contributes to several pathological pathways of AD, targeting APOE4 might serve as a promising strategy for the development of novel drugs to combat AD. In this review, we focus on the recent studies about APOE4-targeted therapeutic strategies that have been advanced in animal models and are being prepared for use in humans for the management of AD.

Background:Oxidative stress is intensely linked with several pathological manifestations. Searching for medicinal plant with the superior safety profile for the treatment of oxidative stress related disorders are ongoing due to multiple unwanted effects associated with synthetic antioxidants. Therefore the purpose of this study was to examine the phytochemical content, in vitro antioxidant potentiality of crude methanol extract (CME), carbon tetrachloride fraction (CTF), petroleum ether fraction (PEF), chloroform fraction (CLF) and ethyl acetate fraction (EAF) of aerial parts of Gnaphalium luteoalbum (GL) L. Methods:The aerial parts of the GL were extracted with methanol followed by fractionation using carbon tetrachloride, petroleum ether, chloroform and ethyl acetate.The phytochemical screening of this plant was performed by using standard methods to evaluate the existence of alkaloids, carbohydrates, phenols, flavonoids, saponins, tannins, terpenoids and fixed oils.Antioxidant potentiality was estimated by, 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl (OH) and nitric oxide (NO) radical scavenging tests. Total antioxidant capacity (TAC), total phenolic content (TPC) and total flavonoid content (TFC) were also measured. Results: Phytochemical analysis of the aerial parts of GL confirmed the presence of carbohydrates, phenols, flavonoids and saponins in crude extract and its all fractions. The CME showed the highest scavenging activity (43.28%) with IC50 of 398.49 μg/mL in the DPPH radical scavenging test. The IC50 values of EAF, CME were statistically significant (P < 0.05, P < 0.01) with respect to ascorbic acid (ACA). For OH and NO radical scavenging tests maximum scavenging (48.39%, 69.64%) was also reported for CME compared to CTF, PEF, CLF and EAF. Compared to ACA, in case of OH and NO radical scavenging activities the IC50 values of CME were markedly significant (P < 0.01, P < 0.05). In the TAC test, CME showed the highest antioxidant activity (absorbance, 2.6 nm) related to other fractions. TPC was found to be the highest in the CME (115.96 mg of gallic acid equivalent/g of dried extract) rather than other fractions. The ranking order of CTF, PEF, CLF, EAF and CME for TFC was 48.67 < 55.75 < 65.29 < 71.35 < 82.29 mg quercetin equivalent/g of dried extract. Conclusion: The existing study suggested that CME of the aerial parts of GL can be used as a natural source of antioxidant which might be effective towards preventing or slowing oxidative stress related disorders.

The therapeutically performance of the pharmaceuticals must be constant and expectable. In order to claim a pharmaceutical to be a quality drug, it must fulfill certain standards and specifications. The quality of pharmaceuticals is strongly related to the patient’s well-being. Quality control (QC) is an historical process in which proof is obtained that the appropriate level of quality has been achieved. QC can have no effect on the quality of the pharmaceuticals. It is merely a measuring process. QC must ensure that all the finished products contain active ingredients that comply with the qualitative and quantitative composition of the finished product described in the product registration dossier. The books containing the standards for drugs and other related substances are known as pharmacopeias. The pharmacopoeias contain a list of drugs and other related substances regarding their source, description, tests, formulas for preparing the same, action and uses, doses, storage conditions, etc. Ophthalmic pharmaceuticals are agents specially designed to be applied to the eyes. Among the drug products, ophthalmic pharmaceuticals are most important since eye is very sensitive and is easily irritated if the composition of the ophthalmic pharmaceutical is not suitable. The QC tests for ophthalmic pharmaceuticals are different in the different pharmacopoeias like IP, BP, and USP. Therefore the aim of this review was to mention QC tests for ophthalmic pharmaceuticals based on quality requirements of the different pharmacopoeias.

To lead a normal life, oxidation is essential owing to carry out normal physiological and biochemical functions that lead to the generation of reactive oxygen species (ROS) plus reactive nitrogen species (RNS)[1]. ROS and RNS such as hydrogen peroxide radicals, hydroxyl radicals, nitric oxide radical, peroxyl radical, superoxide radicals and singlet oxygen are highly reactive molecules and can damage biomolecules including carbohydrates, lipids, proteins, nucleic acids (DNA and RNA) and alter their functions[2-7]. They act in normal physiological cell processes, at low to moderate concentrations, but they produce adverse alterations to cell components, at high concentrations[8-12].Imbalance between the pro-oxidant/antioxidant homeostasis creates oxidative stress that is responsible in the pathogenesis of lifestyle-related diseases for example atherosclerosis, heart disease, arthritis, gastritis, diabetes, cancer, preeclampsia, HIV/AIDS, inflammation, ischemia and neurodegenerative diseases especially Alzheimer’s, Huntington, Parkinson, amyotrophic lateral sclerosis and celiac diseases[13,14]. Antioxidants shield the body from attack of free radical mediated oxidative stress. Antioxidants that are available in nature include retinoids, tocopherols, ascorbic acid (ACA), bioflavonoids (citrin) and polyphenols (hydroxytyrosol)[15,16]. These naturally occurring antioxidants are effective in the prevention of some life threatening diseases include cancer, heart disease, ageing and immune deficiency diseases[17]. Today, the safety of synthetic antioxidants is questionable for many researchers and health specialists. Artificial antioxidants, including butylated hydroxyanisole, butylated hydroxytoluene and propyl gallate are presumed to be oncogenic[18]. ARTICLE INFO ABSTRACT

In the present study the antimicrobial & cytotoxic activity of crude extracts (Chloroform, n-Hexane, Ethyl acetate) of leaves of Lablab purpureus L. were studied. Antimicrobial activity was tested against eleven important pathogenic bacteria including both gram positive and gram negative bacteria and three fungi. The bacteria are B. megaterium, B. subtilis, Staphylococcus aureus, Sarcina lutea, Escherichia coli, Salmonella paratyphi, S. typhi, Shigella boydii, S. dysenteriae and Vibrio mimicus & V. parahemolyticus. Disc diffusion technique was used for invitro antibacterial and antifungal screening. Here kanamycin disc (30g /disc) was used as standard for antibacterial study. The extracts showed antimicrobial activity against most of the bacterial strains with an average zone of inhibition of 8-20mm. The tested fungi are Saccharromyces cerevaceae, Candida albicans and Aspergillus niger. The extracts showed moderate to good antifungal activity with an average 9 -15 mm zone of inhibition. Among the three solvent extracts used, the most effective extract was found to be n-Hexane extract and maximum activity (20 mm, zone of inhibition) found against Staphylococcus aureus with Minimum inhibitory concentration (MIC) values of 64g/ml. The maximum zone of inhibition for chloroform extract showed 17mm against Bacillus subtilis and E.coli with MIC 128g/ml and 32g/ml respectively. The maximum zone of inhibition for Ethyl acetate extract showed 17mm against Vibrio mimicus with MIC values of 64g/ml .Cytotoxicity test was also studied by Brine Shrimp Lethality Bioassay and compare with LC50 values of standard Vincristin sulphate as a positive control. The results illustrated significant cytotoxicity against A. salina, with LC50 13.88µg/ml, 19.17µg/ml and 17.97µg/ml for n-Hexane, Chloroform and Ethyl acetate extracts respectively.

Luffa cylindrica L. (LUCY) and Luffa acutangula (LUAC ) are popular & consumed as vegetables and foods and in folklore medicine to treat various ailments in Bangladesh. The purpose of the present study was to investigate the antioxidant, antibacterial and cytotoxic activities of the n-hexane, chloroform and ethyl acetate extracts of leaves of LUCY & LUAC. Antioxidant and antibacterial activities were evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay and disc diffusion method, respectively. The plants were also assessed for cytotoxic activity by brine shrimp lethality assay. Antioxidant activity of different concentrations of plant extracts were found to increase in a concentration dependent manner. The most prominent activity was found with ethyl acetate extract of LUCY and n-hexane extract of LUAC with an IC 50 value of 50.32 & 50.95 μg/mL, respectively. All extracts/fractions showed low to moderate levels of anti-bacterial activity against most of the tested strains (zone of inhibition = 5–13 mm). All extracts/fractions displayed considerable general toxicity towards brine shrimps. The LC 50 values of the extracts/fractions were of 15.92 to 33.69 μg/mL compared to vincristine sulphate (LC50 = 0.91 μg/mL). This is the first report for cytotoxic activity of LUCY and antibacterial activity of LUAC leaves extracts. On the basis of results obtained, it is suggested that both LUCY and LUAC leaves extracts may be a potential source of natural antioxidants, antimicrobial compounds and anticancer agents to be used in the treatment of various oxidative disorders, infectious diseases caused by resistant microorganisms and cancer, respectively.

In recent years, research on medicinal plants has engrossed a lot of interest worldwide. Large body of proof has been accumulated to reveal promising potential of medicinal plants used in different traditional, complementary and alternative systems. Keeping this in mind, the present study was carried out to scrutinize the antinociceptive and central nervous system (CNS) depressant activity of the methanol extracts of seed (MNLS) and peel (MNLP) of Nephelium longan in young Long-Evans rats. Both types of tests were conducted after oral administration at doses of 250 and 500 mg/kg body weight of rats. CNS activity was evaluated by watching the fall of rats in locomotor and exploratory activities. We also used open field and hole cross tests. The analgesic activity was examined using acetic acid-induced writhing and formalin tests. The results of the statistical analysis showed that the experimental extracts had significant (P < 0.01 and 0.05,) dose dependent CNS depressant and antinociceptive activities. In the acetic acid-induced writhing model, MNLP at dose of 500 mg/kg exerted a maximum of 54.43% inhibition of writhing response, whereas MNLS gave 52.531% inhibition which are comparable to 58.86% inhibition of writhing by standard drug, indomethacin (10 mg/kg). In case of CNS depressant activity, both extracts displayed dose dependent suppression of motor activity and exploratory behavior in the tested models. The results of the study indicate that the plant possesses strong analgesic and central nervous system depressant activity. Key words: Nephelium longan, antinociceptive, indomethacin, CNS depressant activity.