Vanessa Kaplum

Safety evaluation of proanthocyanidin polymer-rich fraction obtained from stem bark of Stryphnodendron adstringens (BARBATIMAO) for use as a pharmacological agent.

The widespread use of medicinal plants among the Brazilian population warrants an assessment of the potential risks associated with their intake. Stryphnodendron adstringens (barbatimão) is one of the most frequently used medicinal plants in Brazil, and the risks associated with its use have yet to be investigated. This study evaluated the genotoxic safety of the use of the proanthocyanidin polymer-rich fraction (F2) of stem bark of S. adstringens. The micronucleus test with 750, 1500, and 2250 mg kg(-1) of F2 administered in Mus musculus (Swiss) outbred mice, showed respectively, 5.0±0.8 (Mean±S.D.), 9.1±1.7, and 10.6±1.9 micronucleated polychromatic erythrocytes (MNPCE). A positive control with cyclophosphamide resulted in 21.0±3.8 MNPCE. Antimutagenicity was also evaluated, by adding 750 mg kg(-1) to cyclophosphamide; the result of 8.7±1.4 showed a protective cytotoxic effect. For the Artemia salina test, 10, 100, and 1000 mg L(-1) of F2 showed, respectively, 8.7±0.6, 7.7±0.6, and 5.7±1.2 survival, i.e., F2 did not inhibit 50% of the population when compared to the control (9.7±0.6). These results indicated that F2 obtained from stem bark of S. adstringens has no genotoxic activity.

In Vitro and In Vivo Activities of 2,3-Diarylsubstituted Quinoxaline Derivatives against Leishmania amazonensis

ABSTRACT Leishmaniasis is endemic in 98 countries and territories worldwide. The therapies available for leishmaniasis have serious side effects, thus prompting the search for new therapies. The present study investigated the antileishmanial activities of 2,3-diarylsubstituted quinoxaline derivatives against Leishmania amazonensis. The antiproliferative activities of 6,7-dichloro-2,3-diphenylquinoxaline (LSPN329) and 2,3-di-(4-methoxyphenyl)-quinoxaline (LSPN331) against promastigotes and intracellular amastigotes were assessed, and the cytotoxicities of LSPN329 and LSPN331 were determined. Morphological and ultrastructural alterations were examined by electron microscopy, and biochemical alterations, reflected by the mitochondrial membrane potential (ΔΨm), mitochondrial superoxide anion (O2·−) concentration, the intracellular ATP concentration, cell volume, the level of phosphatidylserine exposure on the cell membrane, cell membrane integrity, and lipid inclusions, were evaluated. In vivo antileishmanial activity was evaluated in a murine cutaneous leishmaniasis model. Compounds LSPN329 and LSPN331 showed significant selectivity for promastigotes and intracellular amastigotes and low cytotoxicity. In promastigotes, ultrastructural alterations were observed, including an increase in lipid inclusions, concentric membranes, and intense mitochondrial swelling, which were associated with hyperpolarization of ΔΨm, an increase in the O2·− concentration, decreased intracellular ATP levels, and a decrease in cell volume. Phosphatidylserine exposure and DNA fragmentation were not observed. The cellular membrane remained intact after treatment. Thus, the multifactorial response that was responsible for the cellular collapse of promastigotes was based on intense mitochondrial alterations. BALB/c mice treated with LSPN329 or LSPN331 showed a significant decrease in lesion thickness in the infected footpad. Therefore, the antileishmanial activity and mitochondrial mechanism of action of LSPN329 and LSPN331 and the decrease in lesion thickness in vivo brought about by LSPN329 and LSPN331 make them potential candidates for new drug development for the treatment of leishmaniasis.

Unsymmetrical 1,5-diaryl-3-oxo-1,4-pentadienyls and their evaluation as antiparasitic agents.

In this work the synthesis and antiparasitical activity of new 1,5-diaryl-3-oxo-1,4-pentadienyl derivatives are described. First, compounds 1a, 1b, 1c and 1d were prepared by acid-catalyzed aldol reaction between 2-butanone and benzaldehyde, anisaldehyde, p-N,N-dimethylaminobenzaldehyde and p-nitrobenzaldehyde. Reacting each of the methyl ketones 1a, 1b, 1c and 1d with the p-substituted benzaldehydes under basic-catalyzed aldol reaction, we further prepared compounds 2a-2p. All twenty compounds were evaluated for antiproliferative activity, particularly for promastigote of Leishmania amazonensis and epimastigote of Trypanosoma cruzi. All compounds showed good activity while nitro compounds 2i and 2k showed inhibition activity at a few μM.

Oxidative Stress Triggered by Apigenin Induces Apoptosis in a Comprehensive Panel of Human Cervical Cancer-Derived Cell Lines

Recently, the cytotoxic effects of apigenin (4′,5,7-trihydroxyflavone), particularly its marked inhibition of cancer cell viability both in vitro and in vivo, have attracted the attention of the anticancer drug discovery field. Despite this, there are few studies of apigenin in cervical cancer, and these studies have mostly been conducted using HeLa cells. To evaluate the possibility of apigenin as a new therapeutic candidate for cervical cancer, we evaluated its cytotoxic effects in a comprehensive panel of human cervical cancer-derived cell lines including HeLa (human papillomavirus/HPV 18-positive), SiHa (HPV 16-positive), CaSki (HPV 16 and HPV 18-positive), and C33A (HPV-negative) cells in comparison to a nontumorigenic spontaneously immortalized human epithelial cell line (HaCaT). Our results demonstrated that apigenin had a selective cytotoxic effect and could induce apoptosis in all cervical cancer cell lines which were positively marked with Annexin V, but not in HaCaT (control cells). Additionally, apigenin was able to induce mitochondrial redox impairment, once it increased ROS levels and H2O2, decreased the Δψm, and increased LPO. Still, apigenin was able to inhibit migration and invasion of cancer cells. Thus, apigenin appears to be a promising new candidate as an anticancer drug for cervical cancer induced by different HPV genotypes.

Estudo químico e atividades antiproliferativa, tripanocida e leishmanicida de Maxillaria picta

The chemical study of the orchid Maxillaria picta resulted in the isolation of the bioactive stilbenes phoyunbene B and phoyunbene C, in addition to four phenolic acids, one xanthone, steroidal compounds and two triterpenes. Crude extract, fractions, subfractions and the isolated xanthone were evaluated for anticancer activity against human tumor cell lines and against evolutionary forms of T. cruzi and L. amazonensis. The structures of the compounds were determined by GC-MS, and 1H NMR, 13C NMR spectral methods as well as bidimensional techniques.

Proanthocyanidin polymeric tannins from Stryphnodendron adstringens are effective against Candida spp. isolates and for vaginal candidiasis treatment

ETHNOPHARMACOLOGICAL RELEVANCE The stem bark of Stryphnodendron adstringens (Mart.) Coville is popularly used as anti-inflammatory, astringent and in the treatment of wounds and vaginal infections. Several pharmacological activities have been scientifically proven by in vitro and in vivo experimental assays for antibacterial, antiviral, antiprotozoan, anti-inflammatory and antioxidant. AIM OF THE STUDY We investigated whether proanthocyanidin polymeric tannins from the Stryphnodendron adstringens stem bark with antifungal activity against Candida albicans in vitro are also active against planktonic and biofilm cells of Candida non-albicans (CNA, including fluconazole-resistant isolates) and are capable of controlling Candida vaginitis in vivo. MATERIALS AND METHODS A total of 46 clinical isolates and 5 reference Candida spp. strains were used in this study. The antifungal effects in vitro of tannins (F2 and sub-fraction F2.4) from S. adstringens stem bark were evaluated using a broth microdilution assay (for planktonic yeasts and biofilm dispersion cells) or by XTT assay (for biofilm sessile cells). For in vivo antifungal activity analysis, mice with vaginal infection by C. albicans or C. glabrata were treated with a topical gel containing F2 (alone or combined with oral fluconazole), and the vaginal histopathology and fungal burden (by CFU counts from vaginal homogenates) were analyzed. RESULTS F2 and F2.4 inhibited the proliferation of planktonic cells of Candida spp., especially that of fluconazole- and/or amphotericin B-resistant isolates. F2 and F2.4 also inhibited the proliferation of Candida biofilm dispersion cells. Moreover, a gel containing F2 efficiently controlled vaginal infection by C. albicans and C. glabrata in mice, with no noticeable toxicity to vaginal tissue. CONCLUSIONS Our data show that proanthocyanidin polymeric tannins obtained from S. adstringens have antifungal activity in vitro against C. albicans and CNA (including fluconazole-resistant isolates) and presented efficacy in the control of candidiasis in murine model. Therefore, these tannins have potential use in the treatment of vaginal candidiasis, representing interesting alternatives to current antifungals.

Crispoic acid, a new compound from Laelia marginata (Orchidaceae), and biological evaluations against parasites, human cancer cell lines and Zika virus

Abstract The phytochemical study of Laelia marginata (Lindl.) L. O. Williams (Orchidaceae) led to the isolation of a new natural product named crispoic acid (1), together with six other known compounds (2–7). The new natural product was identified as a dimer of eucomic acid and was structurally characterised based upon 1D and 2D NMR and HRMS data. Biological assays with plant crude extract, fractions and isolated compounds were performed against two human cancer cell lines (Hela and Siha), and the tropical parasites Trypanosoma cruzi and Leishmania (Leishmania) amazonensis. The phenantrenoid 9,10-dihydro-4-methoxyphenanthren-2,7-diol 2 was active against Hela and Siha cells (CC50 5.86 ± 0.19 and 20.78 ± 2.72 μg/mL, respectively). Sub-lethal concentrations of the flavone rhamnazin 4 were not able to rescue the viability of the Vero cells infected by Zika virus.

Development, characterization and biocompatibility of chondroitin sulfate/poly(vinyl alcohol)/bovine bone powder porous biocomposite

Chondroitin sulfate (ChS), a sulfated glycosaminoglycan, poly(vinyl alcohol) (PVA) and bovine bone powder (BBP) were blended to form a novel eco-friendly biocomposite through cyclic freeze-thawing under mild conditions. The systematic investigation reveals that the content of BBP has a remarkable effect on the pore size, porosity, mechanical and liquid uptake properties and biodegradability. At 10wt.% BBP the biocomposite exhibited enhanced mechanical properties and biodegradability rate as compared to the pristine sample. Further, different properties of the biocomposite can be tailored according to the content of BBP. In vitro assays showed that ChS/PVA-BBP does not exert cytotoxicity against healthy cells. In vivo and ex vivo experiments revealed that ChS/PVA-BBP biocomposites are biocompatibility materials without exert pro-inflammatory responses. The biocomposite was completely biodegraded and bioresorbed after 15days of treatment. Taken together, BBP is a low-cost source of hydroxyapatite and collagen, which are insurance. All these results suggest that the biocomposite designed in this study is a promising biomaterial for potential skin tissue engineering.

Proanthocyanidin Polymer-Rich Fraction of Stryphnodendron adstringens Promotes in Vitro and in Vivo Cancer Cell Death via Oxidative Stress

Cervical cancer is the fourth most common cancer that affects women, mainly through human papilloma virus (HPV) infection with high-risk HPV16 and HPV18. The present study investigated the in vitro anticancer activity and mechanism of action of a proanthocyanidin polymer-rich fraction of Stryphnodendron adstringens (F2) in cervical cancer cell lines, including HeLa (HPV18-positive), SiHa (HPV16-positive), and C33A (HPV-negative) cells, and also evaluated in vivo anticancer activity. In vitro, cell viability was determined by the MTT assay. Cell migration was determined by the wound healing assay. The mechanism of action was investigated by performing ultrastructural analysis and evaluating reactive oxygen species (ROS) production, mitochondrial metabolism, lipoperoxidation, BCL-2 family expression, caspase expression, and DNA and cell membrane integrity. In vivo activity was evaluated using the murine Ehrlich solid tumor model. F2 time- and dose-dependently reduced cell viability and significantly inhibited the migration of cervical cancer cells. HeLa and SiHa cells treated with F2 (IC50) exhibited intense oxidative stress (i.e., increase in ROS and decrease in antioxidant species) and mitochondrial damage (i.e., mitochondrial membrane potential depolarization and a reduction of intracellular levels of adenosine triphosphate). Increases in the Bax/BCL-2 ratio and caspase 9 and caspase 3 expression, were observed, with DNA damage that was sufficient to trigger mitochondria-dependent apoptosis. Cell membrane disruption was observed in C33A cells (IC50 and IC90) and HeLa and SiHa cells (IC90), indicating progress to late apoptosis/necrosis. The inhibition of ROS production by N-acetylcysteine significantly suppressed oxidative stress in all three cell lines. In vivo, F2 significantly reduced tumor volume and weight of the Ehrlich solid tumor, and significantly increased lipoperoxidation, indicating that F2 also induces oxidative stress in the in vivo model. These findings indicate that the proanthocyanidin polymer-rich fraction of S. adstringens may be a potential chemotherapeutic candidate for cancer treatment.

M1 homeopathic complex trigger effective responses against Leishmania (L) amazonensis in vivo and in vitro

Graphical abstract Figure. No Caption available. HighlightsThere were fewer parasites inside macrophages vacuoles.Parasite load was significantly reduced after M1 treatment.Treatment allowed a delay in evolution of lesions and prevented ulcerative lesions.Cytokines profile were altered increasing Th1 response. Abstract Leishmaniasis is a term referring to a range of clinical conditions caused by protozoan parasites of the genus Leishmania, Trypanosomatidae family, Kinetoplastida order that is transmitted by the bite of certain species of mosquitoes Phlebotominae subfamily. These parasites infect hosts wild and domestic mammals, considered as natural reservoirs and can also infect humans. Leishmania are obligate intramacrophage protozoa that have exclusively intracellular life style. This suggests that the amastigotes possess mechanisms to avoid killing by host cells. Cutaneous leishmaniasis, the most common form of the disease, causes ulcers on exposed parts of the body, leading to disfigurement, permanent scars, and stigma and in some cases disability. Many studies concluded that the cytokines profile and immune system of host have fundamental role in humans and animals natural self‐healing. Conventional treatments are far from ideals and the search for new therapeutic alternatives is considered a strategic priority line of research by the World Health Organization. A promising approach in the field of basic research in homeopathy is the treatment of experimental infections with homeopathic drugs prepared from natural substances associations highly diluted, which comprise a combination of several different compounds considered as useful for a symptom or disease. Therefore, this study aimed to evaluate the effect of M1, a complex homeopathic product, in macrophage‐Leishmania interaction in vitro and in vivo. It was used RAW cells lineage and BALB/c mice as a host for the promastigotes of L. amazonensis (WHOM/BR/75/Josefa). Several biochemical and morphological parameters were determined. Together, the harmonic results obtained in this study indicate that, in general, the highly diluted products trigger rapid and effective responses by living organisms, cells and mice, against Leishmania, by altering cytokines profile, by NO increasing (p < 0.05), by decreasing parasitic load (p < 0.001), and modifying classical maturation and biogenesis of parasitophorous vacuoles (p < 0.001). M1 complex decreased endocytic index (p < 0.001), and the % of infected macrophages (p < 0.05), preventing the development of lesions (p < 0.05) caused by L. amazonensis by increasing Th1 response (p < 0.05). Therefore the M1complex can be a good candidate for a complementary therapy to conventional treatments, since all the parameters observed in vitro and in vivo improved. It could be an interesting clinical tool in association to a classical anti‐parasitic treatment, maybe resulting in better quality of life to the patients, with less toxicity.