Anti-ulcerogenic and analgesic activities of the leaves of Wilbrandia ebracteata in mice

Wilbrandia ebracteata (Cogn.) Cogn. is a medicinal plant belonging to the Cucurbitaceae family used popularly as an antiulcer and analgesic medicine. The hydromethanol extract of leaves was investigated to determine its anti-ulcerogenic (ethanol and indomethacin induced gastric damage) and analgesic (writhing and tail-flick tests) activities in mice (efficacy), its acute toxicity (safety), and its phytochemistry (quality control). Oral administration of leaf extract at a dose of 1000 mg/kg body wt. significantly reduced 73.3% of the total area of lesion in ethanol-induced gastric damage, but was inactive in an indomethacin-induced gastric damage test. The hydromethanol extract was also inactive in both analgesic tests. Oral administration of the leaf extract did not produce mortality in mice, while the LD50 value of the roots was 22.10 mg/kg body wt. in female mice and 58.31 mg/kg body wt. in male mice. Leaves of W. ebracteata reacted positively for steroids, flavonols, flavanones, saponins, tannins and xanthones and negative for other compounds, including cucurbitacins. Leaf extract of W. ebracteata was active as an anti-ulcerogenic, probably through increasing gastric defensive factors, and flavonoids might be the main constituent responsible for this activity.

Evaluation of the anti-inflammatory, analgesic and antipyretic activities of the natural polyphenol chlorogenic acid

Phenolic compounds are numerous and ubiquitous in the plant kingdom, being particularly present in health-promoting foods. Epidemiological evidences suggest that the consumption of polyphenol-rich foods reduces the incidence of cancer, coronary heart disease and inflammation. Chlorogenic acid (CGA) is one of the most abundant polyphenol compounds in human diet. Data obtained from in vivo and in vitro experiments show that CGA mostly presents antioxidant and anti-carcinogenic activities. However, the effects of CGA on the inflammatory reaction and on the related pain and fever processes have been explored less so far. Therefore, this study was designed to evaluate the anti-inflammatory, antinociceptive and antipyretic activities of CGA in rats. In comparison to control, CGA at doses 50 and 100 mg/kg inhibited carrageenin-induced paw edema beginning at the 2nd hour of the experimental procedure. Furthermore, at doses 50 and 100 mg/kg CGA also inhibited the number of flinches in the late phase of formalin-induced pain test. Such activities may be derived from the inhibitory action of CGA in the peripheral synthesis/release of inflammatory mediators involved in these responses. On the other hand, even at the highest tested dose (200 mg/kg), CGA did not inhibit the febrile response induced by lipopolysaccharide (LPS) in rats. Additional experiments are necessary in order to clarify the true target for the anti-inflammatory and analgesic effects of CGA. © 2006 Pharmaceutical Society of Japan.

Myeloperoxidase inhibitory and radical scavenging activities of flavones from Pterogyne nitens

Two new flavone glucosides, nitensosides A and B (1, 2), together with four known compounds, sorbifolin (3), sorbifolin 6-O-β-glucopyranoside (4), pedalitin (5), and pedalitin 6-O-β-glucopyranoside (6) were isolated from Pterogyne nitens. Their structures were elucidated from 1D and 2D NMR analysis, as well as by high resolution mass spectrometry. All the isolated flavones were evaluated for their myeloperoxidase (MPO) inhibitory activity. The most active compound, pedalitin, exhibited IC 50 value of 3.75 nM on MPO. Additionally, the radical-scavenging capacity of flavones 1-6 was evaluated towards ABTS and DPPH radicals and compared to standard compounds quercetin and Trolox®. © 2008 Pharmaceutical Society of Japan.

Synthesis, cytotoxicity, antibacterial and antileishmanial activities of imidazolidine and hexahydropyrimidine derivatives

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In Vitro and In Vivo Activities of Ruthenium(II) Phosphine/Diimine/Picolinate Complexes (SCAR) against Mycobacterium tuberculosis

Rifampicin, discovered more than 50 years ago, represents the last novel class of antibiotics introduced for the first-line treatment of tuberculosis. Drugs in this class form part of a 6-month regimen that is ineffective against MDR and XDR TB, and incompatible with many antiretroviral drugs. Investments in R&D strategies have increased substantially in the last decades. However, the number of new drugs approved by drug regulatory agencies worldwide does not increase correspondingly. Ruthenium complexes (SCAR) have been tested in our laboratory and showed promising activity against Mycobacterium tuberculosis. These complexes showed up to 150 times higher activity against MTB than its organic molecule without the metal (free ligand), with low cytotoxicity and high selectivity. In this study, promising results inspired us to seek a better understanding of the biological activity of these complexes. The in vitro biological results obtained with the SCAR compounds were extremely promising, comparable to or better than those for first-line drugs and drugs in development. Moreover, SCAR 1 and 4, which presented low acute toxicity, were assessed by Ames test, and results demonstrated absence of mutagenicity. © 2013 Pavan et al.