Margareth de Fátima Formiga Melo Diniz

Natural products inhibitors of the enzyme acetylcholinesterase

Alzheimers disease (AD) is a progressive, neurodegenerative pathology that primarily affects the elderly population, and is estimated to account for 50-60% of dementia cases in persons over 65 years of age. The main symptoms associated with AD involve cognitive dysfunction, primarily memory loss. Other features associated with the later stages of AD include language deficits, depression, behavioural problems including agitation, mood disturbances and psychosis. One of the most promising approaches for treating this disease is to enhance the acetylcholine level in the brain using acetylcholinesterase (AChE) inhibitors. The present work reviews the literature on plants and plant-derived compounds inhibitors of enzyme acetylcholinesterase. The review refers to 309 plant extracts and 260 compounds isolated from plants, which are classified in appropriate chemical groups and model tested, and cites their activity. For this purpose 175 references were consulted.

Plants and their active constituents from South, Central, and North America with hypoglycemic activity

There has been marked interest in recent years in the use of plants for the treatment of diabetes. Plants have been found in many countries which have been indicated as having hypoglycemic activity. The present work is an up-to-date review with 178 references of crude plant extracts and chemically defined molecules with hypoglycemic activity from South, Central and North America. The review refers to 224 plants with their families, parts used and type of extract, organism tested and activity. It also includes 40 compounds isolated from those plants. Some aspects of recent research with natural products from plants directed to the treatment of diabetes are discussed.

Gastric and Duodenal Antiulcer Activity of Alkaloids: A Review

Peptic ulcer disease is a deep gastrointestinal erosion disorder that involves the entire mucosal thickness and can even penetrate the muscular mucosa. Numerous natural products have been evaluated as therapeutics for the treatment of a variety of diseases, including this one. These products usually derive from plant and animal sources that contain active constituents such as alkaloids, flavonoids, terpenoids, tannins and others. The alkaloids are natural nitrogen-containing secondary metabolites mostly derived from amino acids and found in about 20% of plants. There has been considerable pharmacological research into the antiulcer activity of these compounds. In this work we review the literature on alkaloids with antiulcer activity, which covers about sixty-one alkaloids, fifty-five of which have activity against this disease when induced in animals.

Metabolic syndrome and risk factors for non-alcoholic fatty liver disease

CONTEXT Non-alcoholic fatty liver disease (NAFLD), hepatic manifestation of metabolic syndrome, has been considered the most common liver disease nowadays, which is also the most frequent cause of elevated transaminases and cryptogenic cirrhosis. The greatest input of fatty acids into the liver and consequent increased beta-oxidation contribute to the formation of free radicals, release of inflammatory cytokines and varying degrees of hepatocytic aggression, whose histological expression may vary from steatosis (HS) to non-alcoholic steatohepatitis (NASH). The differentiation of these forms is required by the potential risk of progression to cirrhosis and development of hepatocellular carcinoma. OBJECTIVE To review the literature about the major risk factors for NAFLD in the context of metabolic syndrome, focusing on underlying mechanisms and prevention. METHOD PubMed, MEDLINE and SciELO data basis analysis was performed to identify studies describing the link between risk factors for metabolic syndrome and NAFLD. A combination of descriptors was used, non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, metabolic syndrome and risk factors. At the end, 96 clinical and experimental studies, cohorts, meta-analysis and systematic reviews of great impact and scientific relevance to the topic, were selected. RESULTS The final analysis of all these data, pointed out the central obesity, type 2 diabetes, dyslipidemia and hypertension as the best risk factors related to NAFLD. However, other factors were highlighted, such as gender differences, ethnicity, genetic factors and the role of innate immunity system. How these additional factors may be involved in the installation, progression and disease prognosis is discussed. CONCLUSION Risk factors for NAFLD in the context of metabolic syndrome expands the prospects to 1) recognize patients with metabolic syndrome at high risk for NAFLD, 2) elucidate pathways common to other co-morbidities, 3) determine risk factors associated with a worse prognosis, 4) develop therapeutic strategies with goal of reducing risk factors, 5) apply acquired knowledge in public health policies focusing on preventive strategies.

Review of the plants with anti-inflammatory activity studied in Brazil

The inflammatory reaction is a response of the organism against an injury and it involves the action of complex events and mediators through of the blood vessels. The present work is a literature survey of the extracts of plants with anti-inflammatory activity studied in Brazil. The review refers to 75 plants with their families, parts used, type of extract used, bioassay models and their activity.

Natural products with antileprotic activity

Leprosy is a chronic infectious disease caused by Mycobacterium leprae bacillus. It was considered to be an incurable disease for ages. Nowadays leprosy is a vanishing disease although we can meet it principally in the tropical zone countries. Brazil has the second greatest number of leprosy cases around the world with almost 30,000 new cases diagnosed in 2005. The present work constitutes a literature review on plant extracts and chemically defined molecules of natural origin showing antileprotic activity. The review refers to 11 plants, their families, and geographical distribution, the utilized parts, the type of extract and the tested organism. It also includes 17 compounds isolated from higher plants and microorganisms, classified into appropriate chemical groups. Some aspects of recent antileprotic-activity-directed research on natural products are discussed. For this purpose 63 references were consulted.

Anti-Inflammatory Activity of Alkaloids: An Update from 2000 to 2010

Many natural substances with proven anti-inflammatory activity have been isolated throughout the years. The aim of this review is to review naturally sourced alkaloids with anti-inflammatory effects reported from 2000 to 2010. The assays were conducted mostly in vivo, and carrageenan-induced pedal edema was the most used experimental model. Of the 49 alkaloids evaluated, 40 demonstrated anti-inflammatory activity. Of these the most studied type were the isoquinolines. This review was based on NAPRALERT data bank, Web of Science and Chemical Abstracts. In this review, 95 references are cited.

Anxiolytic-like activity and GC–MS analysis of (R)-(+)-limonene fragrance, a natural compound found in foods and plants

The traditional use of essential oils in aromatherapy has offered numerous health benefits. However, few scientific studies have been conducted with these oils to confirm their therapeutic efficacy. (+)-Limonene is a chemical constituent of various bioactive essential oils. The present study reports on the anxiolytic-like effects of (+)-limonene in an elevated maze model of anxiety in mice. At concentrations of 0.5% and 1.0%, (+)-limonene, administered to mice by inhalation, significantly modified all the parameters evaluated in the elevated plus maze test. The pharmacological effect of inhaled (+)-limonene (1%) was not blocked by flumazenil. Analysis of (+)-limonene using gas chromatography-mass spectrometry (GC-MS) showed its volatility to be high. These data suggest possible connections between the volatility of (+)-limonene and its anxiolytic-like effect on the parameters evaluated in the elevated plus maze test. The data indicate that (+)-limonene could be used in aromatherapy as an antianxiety agent.

Effect of the activity of the Brazilian polyherbal formulation: Eucalyptus globulus Labill, Peltodon radicans Pohl and Schinus terebinthifolius Radd in inflammatory models

The Brazilian polyherbal formulation (BPF) is composed by dyes of Eucalyptus globulus Labill, Peltodon radicans Pohl and Schinus terebinthifolius Raddi in alcohol at 13.3° GL. The formulation is popularly used in Paraiba state, Brazil since 1889 and it is used as an antiseptic and anti-inflammatory medicine. The aim of this study was to evaluate the anti-inflammatory property of the polyherbal formulation. For this purpose it was used the12-O-tetradecanoylphorbol 13-acetate (TPA) and capsaicin-induced mouse ear edema and the carrageenan-induced rat paw edema. The BPF at dose of 26 mL/Kg inhibited both 12-O-tetradecanoylphorbol 13-acetate (TPA) and capsaicin-induced ear edema by 49% (p < 0.05) and 24% (p < 0.01) respectively. Preliminary results on carrageenan-induced rat paw edema demonstrated that oral administration also inhibited the paw edema by approximately 29%. The results demonstrate that the Brazilian polyherbal formulation has anti-inflammatory activity and the better dose was the one used by the population.

Ultrastructural study on the morphological changes to male worms of Schistosoma mansoni after in vitro exposure to allicin

INTRODUCTION Garlic has a wide range of actions, including antibacterial, antiviral, antifungal, antiprotozoal and anthelmintic actions. This antiparasitic activity has been attributed to allicin, which is the main constituent of garlic. The present study aimed to investigate the in vitro activity of allicin on the tegument of adult Schistosoma mansoni worms using scanning electron microscopy. METHODS Swiss Webster mice were infected with S. mansoni cercariae (100 per mouse) and sacrificed 50 days later to acquire the adult worms. These worms were collected by perfusion and placed in RPMI medium 1,640 at 37°C before transferring to RPMI media containing 0 (control), 5, 10, 15 and 20mg/mL of allicin, where they were incubated for 2h. The worms were fixed in 2.5% glutaraldehyde solution, washed twice, post-fixed in osmium tetroxide, washed twice and then dehydrated with ascending grades of ethanol. The samples were air-dried, mounted on stubs, gold coated in an ion sputtering unit and viewed using a scanning electron microscope. RESULTS A concentration of 5mg/mL caused wrinkling in the tegument; a concentration of 10mg/mL resulted in changes to tubercles and loss or modification of spines. With 15 and 20mg/mL increasing damage to the tegument could be seen, such as vesicle formation and the presence of ulcers. CONCLUSIONS These findings demonstrate the effect of allicin on adult S. mansoni worms and indicate that most of the changes occur at concentrations greater than that normally indicated for treatment.