Amelia Teresinha Henriques

Behavioral and genoprotective effects of Vaccinium berries intake in mice

Studies have shown that supplementation with berries rich in anthocyanins are effective in reducing oxidative stress associated with aging, and are beneficial in reversing age-related neuronal and behavioral changes. However, there are few reports on other biological activities of these polyphenols, such as genoprotective effects. The present experiments were performed to study the possible effects of 30-day administration of a lyophilized extract of Vaccinium ashei berries on cognitive performance using step-down inhibitory avoidance, open-field habituation and elevated plus-maze tasks, as well as on DNA damage in the hippocampus and cerebral cortex. The present study showed that the extract significantly enhanced long-term memory in the inhibitory avoidance task, induced an increase in the number of crossings during open-field habituation and had an anxiolytic effect in the elevated plus-maze task. Moreover, the extract reduced oxidative DNA damage in brain tissue in vitro. These results suggest that supplementation with V. ashei berries to mice improves performance on memory tasks and has a protective effect on DNA damage, possibly due to the antioxidant activity of polyphenols, including anthocyanins.

Evaluation of some pharmacological activities of Eugenia uniflora L.

In view of the extensive use of Eugenia uniflora in folk medicine, different extracts of dried and fresh leaves of the plant were assayed to test its possible pharmacological activities. The infusion of fresh leaves had a highly significant anti-inflammatory effect when administered p.o. to rats 1 h before subplantar injection of carrageenin. The infusion increased the pentobarbital sleeping time and also had an effect on intestinal transit, and had no acute toxic effect. No analgesic or antimicrobial activities were observed with any of the extracts used.

Antiinflammatory and antinociceptive activities of extracts and isolated compounds from Stachytarpheta cayennensis

The alcoholic and n-butanolic extracts of dried leaves of Stachytarpheta cayennensis (L.C. Rich) Vahl (Verbenaceae) was assessed in antiinflammatory and antinociceptive models. Intraperitoneal pretreatment with the dried extracts at doses ranging from 100 to 200 mg/kg, significantly inhibited carrageenin inducing edema formation. The active extracts were then fractionated and monitored with the same bioassay. The iridoid ipolamiide and the phenylethanoid glycoside acteoside were isolated from the active fraction and showed inhibitory effect on histamine and bradykinin induced contractions of guinea-pig ileum. The compounds also showed in vivo antiinflammatory activity when administered orally to rats mainly in the fourth hour after the administration of the phlogistic agent (70.22% and 93.99%, respectively). These results indicate that S. cayennensis shows antiinflammatory properties which seems to be due, at least partly, to the inhibition of bradyknin and histamine. The extracts also exhibited antinociceptive activity measured by the hot-plate test both i.p. and p.o. in doses ranging from 100 to 300 mg/kg.

Screening of plants used in south Brazilian folk medicine

Thirty-seven species of medicinal plants used in folk phytotherapy were chemically screened for alkaloids, coumarins, flavonoids, anthraquinones, saponins, sterols and/or triterpenes and tannins. Seven of these were also screened for the presence of mutagenic activity using the Ames test (Salmonella/microsome).

Anticancer, antichemotactic and antimicrobial activities of marine sponges collected off the coast of Santa Catarina, southern Brazil

Abstract This study reports the in vitro screening of 10 marine sponges (Porifera) collected from the coastline of Santa Catarina, southern Brazil, in the search for novel pharmaceuticals. Organic and aqueous extracts were tested for anticancer, antibacterial, antifungal and antichemotactic activities. Eight of the ten species tested demonstrated activity in one or more of the bioassays. Organic extracts of Polymastia janeirensis Boury-Esnauls, 1973, Haliclona aff tubifera George and Wilson, 1919, Mycale arcuiris Lerner and Hajdu, 2002 and Raspailia ( syringella ) sp. each demonstrated cytotoxicity at 100 μg/ml in an in vitro screening assay against the HT29 colorectal tumour cell line. Further analysis against three human tumour cell lines (HT29, U373 and NCI-H460) demonstrated IC 50 concentrations ranging from 25 to 50 μg/ml. Aqueous extracts of six species P. janeirensis , M. arcuiris , Raspailia ( syringella ) sp., Guitarra sp., Tedania ignis Duchassaing and Michelotti, 1864 and Pseudaxinella reticulata Ridley and Dendy, 1886 each significantly ( p ≤0.05) retarded the migration of polymorphonuclear (PMN) leukocytes in a chemotactic assay. In antibacterial assays, only H. aff tubifera (four of five bacterial strains) and Axinella corrugata George and Wilson, 1919 (one of five bacterial strains) demonstrated activity. None of the 10 species demonstrated measurable antifungal activity. These extracts are currently undergoing further analysis to identify the active constituents.

Alkaloids as a source of potential anticholinesterase inhibitors for the treatment of Alzheimer's disease

The inhibition of acetylcholinesterase (AChE), the key enzyme in the breakdown of acetylcholine, is currently the main pharmacological strategy available for Alzheimers disease (AD). In this sense, many alkaloids isolated from natural sources, such as physostigmine, have been long recognized as acetyl‐ and butyrylcholinesterase (BChE) inhibitors. Since the approval of galantamine for the treatment of AD patients, the search for new anticholinesterase alkaloids has escalated, leading to promising candidates such as huperzine A. This review aims to summarize recent advances in current knowledge on alkaloids as AChE and BChE inhibitors, highlighting structure–activity relationship (SAR) and docking studies.

Genotoxic effects of structurally related β-carboline alkaloids

Abstract β-Carboline alkaloids, found in medicinal plants, tobacco smoke and well-cooked foods, have shown a variety of actions in biological systems related to their interaction with DNA. Therefore, these alkaloids can be considered potentially mutagenic. In this work, the genotoxic, mutagenic, and cytotoxic activities of three aromatic β-carboline alkaloids (harman, harmine, and harmol) and two dihydro-β-carboline alkaloids (harmaline and harmalol) were evaluated by means of the Salmonella/microsome assay ( Salmonella typhimurium TA98, TA97, TA100, and TA102) and SOS chromotest ( Escherichia coli PQ37) with and without metabolic activation. Moreover, harman and harmine were analyzed by the micronucleus assay in vivo. It was shown that genotoxicity was inhibited by the addition of S9 mix for aromatic β-carbolines harman and harmol in TA97. However, harmine showed signs of mutagenicity only in the presence of S9 mix in TA98 and TA97 frameshift strains. In the SOS chromotest, only harman induced SOS functions in the absence of S9 mix. Dihydro-β-carbolines were not genotoxic in any of the microorganisms used. The negative responses obtained in the micronucleus assay indicated that harman and harmine were not able to induce chromosomal mutations.

Acaricidal properties of the essential oil from Hesperozygis ringens (Lamiaceae) on the cattle tick Riphicephalus (Boophilus) microplus.

Hesperozygis ringens (Benth.) Epling (Lamiaceae) is a strongly aromatic plant employed popularly for its antiparasitic properties. The leaves afforded 4% of essential oil constituted mainly by pulegone (86%). Laboratory tests were carried out to determine the toxicity of the essential oil species on engorged females and larvae of the cattle tick Riphicephalus (Boophilus) microplus using the adult immersion test (AIT) and the larval immersion test (LIT). It was observed that the essential oil at the concentration of 50 microL/mL and 25 microL/mL inhibited the egg laying significatively in relation to the controls and the eggs from these treated females were affected by the oil; the hatching was inhibited in 95% and 30%, respectively. In the LIT it was verified that the LC(99.9), LC(50) and LC(1) was 0.541 microL/mL, 0.260 microL/mL and 0.015 microL/mL, respectively. Pulegone, isolated from the oil, showed similar effect on the females and on the larvae, indicating that it is responsible for the oil activity.

Aromatic Plants from Brazil. II. The Chemical Composition of Some Eugenia Essential Oils

ABSTRACT Essential oils were obtained from the leaves of six Eugenia species collected from different areas of Brazil and were analyzed by GC and GC/MS. Forty-four compounds representing 89.6–95.7% of the oils were identified. Only Eugenia schuechiana and E. plicato-costata showed considerable amounts of monoterpenes: among them, α-pinene was the most abundant (13.2 and 20.9%). In all analyzed samples, bicyclic sesquiterpenes were present, particularly the selinene group (41%) in E. uniflora; another group of hydrocarbon and oxygenated sesquiterpenes, this time with the aromadendrene nucleus, was found in all samples in different amounts. The oils of E. rostrifolia and E. involucrata were found to be especially rich in sesquiterpene hydrocarbons (77.7% and 84.4%), with considerable amounts of viridiflorene (>30%); β-caryophyllene and its oxide are the main components of the essential oil of E. schuechiana and E. plicato-costata (31.9% and 26.9%), while E. uniflora and E. tinguyensis were characterized by ...

Óleos voláteis de espécies de Myrcia nativas do Rio Grande do Sul

Essential oils from M. richardiana, M. arborescens, M. selloi, M. oligantha, M. rostrata, M. lajeana, M. obtecta, M. pubipetala and M. hatschbachii were obtained by hydrodistillation and analyzed by GC and GC/MS. Sixty-seven compounds have been identified ranging from 90-99% of the oil contents. All analyzed species were rich in cyclic sesquiterpenes (66-99%), mainly those from the cadinane, caryophyllane and germacrane cyclization pathway, among them b-caryophyllene, germacrene D, bicyclogermacrene, d-cadinene, spathulenol, caryophyllene oxide, globulol and a-cadinol. The acyclic sesquiterpene series was well represented by M. lajeana (32.1%), with 25,3% of (E)-nerolidyl acetate.