Pectin-like Polysaccharide Extracted from the Leaves Caesalpinia pulcherrima is a Promising Antioxidant and Immunomodulator Agent

Abstract Studies have shown that Caesalpinia pulcherrima extracts promote antioxidant, healing, immunomodulating and antiparasitic activities and its polysaccharides can be used as functional food. In this sense, this work had as objective the isolation and characterization of a polysaccharide-like pectin, extracted from the C. pulcherrima leaves and its possible applications as an antioxidant and immunomodulator agent. The molecule was characterized by high performance liquid chromatography, fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. Its antioxidant potential was evaluated through the methods of phosphomolybdenum, ABTS radical scavenging [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid], DPPH (1,1-diphenyl-2-picrylhydrazyl) and nitric oxide radical. The immunostimulating effects of pectin were tested in splenocytes to evaluate its toxic, proliferative and cell activator and immunomodulatory potential. The polysaccharide obtained has structural characteristics similar to pectins. Pectin showed high in vitro antioxidant activity for ABTS radical scavenging, moderate activity for phosphomolybdenum and low activity for DPPH and nitric oxide. In vitro immunomodulation assays showed that pectin obtained did not promote a cytotoxic effect (viability > 90%). The increase in cytosolic ROS levels indicates a possible mechanism of cell activation without causing damage. Immunophenotyping showed that pectin increased a subpopulation of CD8+ T lymphocytes and monocytes. In addition, it promoted a mostly pro-inflammatory response confirmed by the production of cytokines IL-2, -4, -6, IFN-γ and TNF-α. These results reinforce the ethnopharmacological use of C. pulcherrima leaves and expand the use of this plant for future applications as herbal medicines.

Ability of two new thiazolidinediones to downregulate proinflammatory cytokines in peripheral blood mononuclear cells from children with asthma

Allergic asthma is a chronic, complex inflammatory disease of the airway. Despite extensive studies on the immunomodulation of T helper (Th) cell pathways (i.e., Th1 and Th2) in asthma, little is known about the effects of Th17 pathway modulation, particularly that involving peroxisome proliferator-activated receptors (PPARs). In response, two new thiazolidinedione derivatives-namely, LPSF-GQ-147 and LPSF-CR-35 were synthesized and evaluated for their immunomodulatory effects on Th17-related cytokines, including interferon γ (IFNγ), interleukin IL-6, IL-17, and IL-22 in the peripheral blood mononuclear cells of asthmatic children. Both compounds were nontoxic even at high concentrations (i.e., 100 µM). The LPSF-CR-35 compound significantly reduced the levels of IL-17A (p = .039) and IFNγ (p = .032) at 10 µM. For IL-22 and IL-6, significant reduction occurred at 100 µM (p = .039 and p = .02, respectively). Conversely, LPSF-GQ-147 did not significantly inhibit the production of the tested cytokines, the levels of all of which were more efficiently reduced by LPSF-CR-35 than methylprednisolone, the standard compound. Real-time polymerase chain reaction assay confirmed that LPSF-GQ-147 has significant PPARγ modulatory activity. Such data indicate that both LPSF-CR-35 and LPSF-GQ-147 are promising candidates as drugs for treating inflammation and asthma

Synthesis and biological evaluation of novel imidazolidine derivatives as candidates to schistosomicidal agents

ABSTRACT Introduction: Schistosomiasis is an infectious parasitic disease caused by trematodes of the genus Schistosoma, which threatens at least 258 million people worldwide and its control is dependent on a single drug, praziquantel. The aim of this study was to evaluate the anti-Schistosoma mansoni activity in vitro of novel imidazolidine derivatives. Material and methods: We synthesized two novel imidazolidine derivatives: (LPSF/PTS10) (Z)-1-(2-chloro-6-fluorobenzyl)-4-(4-dimethylaminobenzylidene)-5-thioxoimidazolidin-2-one and (LPSF/PTS23) (Z)-1-(2-chloro-6-fluoro-benzyl)-5-thioxo-4-(2,4,6-trimethoxy-benzylidene)-imidazolidin-2-one. The structures of two compounds were determined by spectroscopic methods. During the biological assays, parameters such as motility, oviposition, mortality and analysis by Scanning Electron Microscopy were performed. Results: LPSF/PTS10 and LPSF/PTS23 were considered to be active in the separation of coupled pairs, mortality and to decrease the motor activity. In addition, LPSF/PTS23 induced ultrastructural alterations in worms, after 24 h of contact, causing extensive erosion over the entire body of the worms. Conclusion: The imidazolidine derivatives containing the trimetoxy and benzylidene halogens showed promising in vitro schistosomicidal activity.

Tegumental Changes in Adult Schistosoma mansoni Induced by a New Imidazolidinic Derivative.

Aims: Verify the potential of the schistosomicidal imidazolidine derivative (5Z)-3-(4- bromo-benzyl)-5-(4-chloro-benzylidene)-4-thioxo-imidazolidin-2-one. Study Design: In this study, we tested the imidazolidinic derivative 3 through in vitro evaluations, cytotoxicity assay and analysis of Scanning Electron Microscopy to verify its therapeutic potential in the treatment of schistosomiasis. Place and Duration of Study: Departamento de Antibióticos, Universidade Federal de Pernambuco (UFPE), Fundação Oswaldo Cruz (FIOCRUZ)/PE and (FIOCRUZ)/BA between January 2013 and march 2014. Methodology: This study was approved by the Ethics Committee on Animal Use Research Center Aggeu Magalhães/Oswaldo Cruz Fundação (CPqAM/FIOCRUZ) authorized by the license No. 21/2011. Male albino Swiss mice were used Mus musculus 25 days old weighing 50 grams. Compound 3 was assayed for its cytotoxicity through cell J774 macrophage lineage. The amount of inhibitory concentration (LC50) was determined by nonlinear regression using the Graph Pad Prism version 5.01. Then the compound was evaluated against adult worms of S. mansoni by performing the activity in vitro at doses 100-20μg/mL and ultrastructural investigation by Scanning Electron Microscopy (SEM) at doses of 100 and 60μg/ml. The PZQ was the positive control of the experiment. Results: The derivative 3 showed LC50 of 29.7±3.9mM. Compound 3 was able to have decreased motility of S. mansoni culminating with a mortality rate of 100% at doses of 60 and 100μg/mL on the fourth day of observation of the experiment. In the SEM, the compound caused various soft tissue changes of S. mansoni parasites such as blistering, destruction of the integument with loss of spines and tubercles, body contraction and windy. Conclusion: The derivative imidazolidine 3 showed a promising schistosomicidal activity in vitro. However, conducting further studies with the completion of work in front of the live schistosomiasis is required.

Activity Anti-Inflammatory and in silico Study of New Thiazolidinedione Derivatives.

Aims: Evaluation of the anti-inflammatory properties of new thiazolidine-2,4-diones derivatives. Study Design: Study the effects of new thiazolidine-2,4-diones derivatives on the inflammatory process. Place and Duration of Study: Departamento de Antibióticos, Universidade Federal de Pernambuco (UFPE), between June 2011 and July 2012. Methodology: Compounds thiazolidine-2,4-diones were tested for anti-inflammatory activity by air pouch model. Swiss albino mice were used for the study. Air cavities were produced by subcutaneous injection of 2.5 mL of sterile air into the intrascapular area of the back. An additional 2.5 mL of air was injected into the cavity every 3 days to keep the space open. Seven days after the initial air injection, 1 mL of a 1% solution of carrageenan dissolved in saline was injected directly into the pouch to produce an inflammatory response. The compoundsthiazolidine-2,4-diones and standard piroxicam were tested at doses of 3 mg/kg body weight. The total number of polymorphonuclear leukocytes (PMNL) was countedusing an improved. Results: The results support the use of these derivatives in inflammatory process. Among the compounds tested the ones that showed a greater effect in inhibiting the migration of neutrophils were the 3a, 3b, 3c, 3d and 3e. The anti-inflammatory effects showed by 3a-j were promising, probably due to the duality of action on PPAR alpha and gamma. Conclusion: In conclusion, this study has shown that the thiazolidine derivatives do possess significant anti-inflammatory effects in laboratory animals. The exact mechanism and the bioactive principles responsible for these actions remain to be explained.