Antiprotozoal action of synthetic cinnamic acid analogs

Abstract INTRODUCTION Leishmaniasis, Chagas disease, and malaria cause morbidity globally. The drugs currently used for treatment have limitations. Activity of cinnamic acid analogs against Leishmania spp., Trypanosoma cruzi, and Plasmodium falciparum was evaluated in the interest of identifying new antiprotozoal compounds. METHODS In vitro effects of analogs against L. braziliensis, L. infantum chagasi, T. cruzi, and P. falciparum, and hemolytic and cytotoxic activities on NCTC 929 were determined. RESULTS Three analogs showed leishmanicidal and tripanocidal activity. No antiplasmodial, hemolytic, or cytotoxic activity was observed. CONCLUSIONS Antiprotozoal activity of analogs against L. infantum braziliensis, L. infantum chagasi, and T. cruzi was demonstrated.

Screening of natural phenolic compounds for potential to inhibit bacterial cell division protein FtsZ.

FtsZ plays an important role in bacterial cell division by polymerizing to form the Z ring at the site of cytokinesis. Phytochemicals are known to disrupt bacterial cell division through inhibition of FtsZ assembly. In the present study phytochemicals like eugenol, trans-cinnamic acid, 4-formyl cinnamic acid, naringenin and caffeic acid were were tested for their potential to inhibit cell division. Effect of these antimicrobial compounds on the growth of E. coli was determined and the inhibition of FtsZ assembly in vitro was investigated. The present study revealed trans-cinnamic acid as the most potent inhibitor of FtsZ assembly.

Studies on interactions between plant secondary metabolites and glutathione transferase using fluorescence quenching method.

The interactions between plant secondary metabolites (tannic acid, rutin, cinnamic acid and catechin) and glutathione transferase (GST) were investigated by fluorescence and UV-Vis absorption spectroscopy. Intrinsic fluorescence of GST was measured by selectively exciting their tryptophan (Trp) residues and quenching constants were determined using the Stern-Volmer equation. The binding affinity was found to be strongest for tannic acid and ranked in the order tannic acid>rutin>cinnamic acid>catechin. The pH values in the range of 6.7-7.9, except for tannic acid, did not affect significantly the affinity of rutin, cinnamic acid and catechin with GST. Results showed that the fluorescence quenching of GST was a static_quenching. Fluorescence quenching and UV-Vis absorption spectroscopy suggested that only the tannic acid changed the microenvironment of the Trp residues. Furthermore, the number of binding sites and binding constants at different pH values showed that tannic acid had strongest affinity towards GST and hydrogen bonding played an important role in the affinity between GST and the metabolites.

Main phenolic compound of petals of Echium Amoenum fisch. and C. A. mey., a famous medicinal plant of Iran

Echium amoenum Fisch. and C.A. Mey. [Boraginaceae] is an indigenous Iranian plant, that its dry violet-blue petals [Gol-e-Gavzaban] have long been used in traditional medicine of Iran. In this study concentrated metanolic extract of the grounded dried petals of E. amoenum was fractionated by column chromatography and the fractions were purified by preparative HPLC. The structure of main pure component which was characterized by UV, IR, one and two dimensional 1H and 13C-NMR and Mass spectroscopy was found to be rosmarinic acid which is widespread in the plants of the Lamiaceae and Boraginaceae families in insignificant quantities and has antimicrobial, antiviral, and anti-inflammatory effects

Pharmacology of rosemary (Rosmarinus officinalis Linn.) and its therapeutic potentials.

The use of plants is as old as the mankind. Natural products are cheap and claimed to be safe. They are also suitable raw material for production of new synthetic agents. Rosemary (Rosmarinus officinalis Linn.) is a common household plant grown in many parts of the world. It is used for flavouring food, a beverage drink, as well as in cosmetics; in folk.medicine it is used as an antispasmodic in renal colic and dysmenorrhoea, in relieving respiratory disorders and to stimulate growth of hair. Extract of rosemary relaxes smooth muscles of trachea and intestine, and has choleretic, hepatoprotective and antitumerogenic activity. The most important constituents of rosemary are caffeic acid and its derivatives such as rosmarinic acid. These compounds have antioxidant effect. The phenolic compound, rosmarinic acid, obtains one of its phenolic rings from phenylalanine via caffeic acid and the other from tyrosine via dihydroxyphenyl-lactic acid. Relatively large-scale production of rosmarinic acid can be obtained from the cell culture of Coleus blumei Benth when supplied exogenously with phenylalanine and tyrosine. Rosmarinic acid is well absorbed from gastrointestinal tract and from the skin. It increases the production of prostaglandin E2 and reduces the production of leukotriene B4 in human polymorphonuclear leucocytes, and inhibits the complement system. It is concluded that rosemary and its constituents especially caffeic acid derivatives such as rosmarinic acid have a therapeutic potential in treatment or prevention of bronchial asthma, spasmogenic disorders, peptic ulcer, inflammatory diseases, hepatotoxicity, atherosclerosis, ischaemic heart disease, cataract, cancer and poor sperm motility.

Picrorhiza kurroa (Kutaki) Royle ex Benth as a hepatoprotective agent--experimental & clinical studies.

Picrorhiza kurroa (Pk), a known hepatoprotective plant, was studied in experimental and clinical situtations. The standardization of active principles--Picroside 1 and 2 was done with High Performance Liquid Chromatography. Picroside 1 ranged from 2.72 to 2.88 mg/capsule and picroside 2 from 5.50 to 6.00 mg/capsule. In the galactosamine-induced liver injury in rats, Pk at a dose of 200 mg/kg p.o. showed a significant reduction (p < 0.05) in liver lipid content, GOT and GPT. In a randomised, double-blind placebo controlled trial in patients diagnosed to have acute viral hepatitis (HBsAg negative), Pk root powder 375 mg three times a day was given for 2 weeks (n = 15) or a matching placebo (n = 18) was given. Difference in values of bilirubin, SGOT and SGPT was significant between placebo and Pk groups. The time in days required for total serum bilirubin to drop to average value of 2.5 mg% was 75.9 days in placebo as against 27.44 days in Pk group. The present study has shown a biological plausability of efficacy of Pk as supported by clinical trial in viral hepatitis, hepatoprotection in animal model and an approach for standardizing extracts based on picroside content.