Medicinal plants from Mexico used in the treatment of scorpion sting

Scorpion sting envenomation is a major public health in Mexico. Rural communities rarely have antivenoms in the health centers, therefore, the people commonly resort to using medicinal plants to treat the symptoms of envenoming caused by scorpion venom, but this knowledge has not yet been reported in detail. In this review, we carry out a review of the medicinal plants used in Mexico against scorpion stings. PubMed, Google, Science Direct, and the Digital Library of Mexican Traditional Medicine (DLMTM) were used to collect data. The results showed the use of at least 48 medicinal plants distributed in 26 families, where Fabaceae (14.6%), Lamiaceae (10.4%), and Asteraceae (10.4%) have the maximum representation. The application of leaves (32%) was preferred followed by roots (20%), stem (17.3%), flowers (16%), and bark (8%). In addition, the most common method of use to treat scorpion stings is decoction (32.5%). The oral and topical routes of administration have similar percentages of use. In vitro and in vivo studies of Aristolochia elegans, Bouvardia ternifolia, and Mimosa tenuiflora were found, which showed an antagonistic effect on the contraction of the ileum caused by the venom of C. limpidus, likewise, they increased the LD₅₀ of said venom and even B. ternofila showed reduced albumin extravasation. The results of these studies demonstrate the promising use of medicinal plants for future pharmacological applications; nevertheless, validation, bioactive compound isolation and toxicity studies are necessary to support and improve therapeutics.

Alpha-terthienyl increases filamentous actin of Entamoeba histolytica

This study aimed to know if alpha terthienyl (α-T) affects E. histolytica viability and to analyze its effect on the actin cytoskeleton. Trophozoites of E. histolytica HM1-IMSS were treated with α-T, then, cell viability and morphology were evaluated using tetrazolium salts and scanning electron microscopy, respectively; while actin filaments (F-actin) were stained with rhodamine-phalloidin, observed by confocal microscopy and quantified by fluorometry. Data showed that α-T inhibited cell viability of trophozoites (IC₅₀, 19.43 µg / mL), affected the cell morphology, and increased the F-actin in a dose-dependent manner. Production of reactive oxygen species and RhoA-GTP levels remained normal in α-T-treated amebas. Two inhibitors that affect the organization of the trophozoites cytoskeleton, one that interacts directly with actin, Cytochalasin D (CD), and one that affects the Rho signaling pathway by inhibiting the downstream effector Rock, Y27632, were tested. Y27632 did not affect the increase of polymerized actin observed with α-T, this compound partially ameliorates the potent disrupting effects of CD on actin filaments. Docking results suggest that α-T could be an antagonist of CD for the same interaction zone in actin, however, more studies are needed to define the action mechanism of this compound.

Vorinostat as potential antiparasitic drug

OBJECTIVE

Vorinostat is a drug used to treat cutaneous T cell lymphoma whose action mechanism is based on Histone Deacetylase inhibition. Histone Deacetylases are a family of enzymes that remove acetyl groups from histone and non-histone proteins that control many crucial processes, such as gene regulation, cell cycle progression, differentiation, and apoptosis. Histone Deacetylase homologues are also expressed in parasites of the genus Plasmodium, Leishmania, Cryptosporidium, Schistosoma, Entamoeba, and others. In this way, antiparasitic properties of Vorinostat have been explored. The aim of this review is to report the current state knowledge of Vorinostat as antiparasitic drug against Plasmodium, Leishmania, Cryptosporidium, Schistosoma and Entamoeba in order to support future investigation in this field.

MATERIALS AND METHODS

The authors revised the recent and relevant literature concerning the topic and discussed advances and limitations of studies on Vorinostat as potential drug to treat human parasitic diseases.

RESULTS

Vorinostat has been efficient in vitro and, in some cases, in vivo, against parasites that cause parasitic diseases, such as malaria, leishmaniasis, cryptosporidiosis, amoebiasis, and schistosomiasis.

CONCLUSIONS

In vitro and in vivo models have demonstrated the antiparasitic activity of Vorinostat, however, the challenge is to assay its activity in animal models and to evaluate if Vorinostat is safe for humans as new alternative to treat human parasitic infections.

Linearolactone and Kaempferol Disrupt the Actin Cytoskeleton in Entamoeba histolytica: Inhibition of Amoebic Liver Abscess Development

Linearolactone (1) and kaempferol (2) have amebicidal activity in in vitro studies. The type of cell death induced by 1 and 2 and their effects on the virulence of E. histolytica were analyzed by transmission and confocal electron microscopy, reactive oxygen species (ROS) production, and apoptosis, detected by flow cytometry with dichlorofluorescein 2',7'-diacetate and annexin-V binding, respectively, and confirmed by TUNEL. The interaction of 1 and 2 with actin was analyzed by docking, and the in vivo amoebicidal activity was established with the Mesocricetus auratus model; amebic liver abscess (ALA) development was evaluated by magnetic resonance (MR) and validated post mortem. In vitro, compounds 1 and 2 caused chromatin condensation, intracellular ROS, and loss of actin structures. Coupling analysis showed that they bind to the allosteric and catalytic sites of actin with binding energies of -11.30 and -8.45 kcal/mol, respectively. Treatments with 1 and 2 induced a decrease in ALA formation without toxic effects on the liver and kidney. Thus, compound 1, but not 2, was able to induce apoptosis-like effects in E. histolytica trophozoites by intracellular production of ROS that affected the actin cytoskeleton structuration. In vivo, compound 1 was more active than compound 2 to reduce the development of ALA.

Mangiferin-Loaded Polymeric Nanoparticles: Optical Characterization, Effect of Anti-topoisomerase I, and Cytotoxicity

Mangiferin is an important xanthone compound presenting various biological activities. The objective of this study was to develop, characterize physicochemical properties, and evaluate the anti-topoisomerase activity of poly(lactic-co-glycolic acid) (PLGA) nanoparticles containing mangiferin. The nanoparticles were developed by the emulsion solvent evaporation method and the optimal formulation was obtained with a response surface methodology (RSM); this formulation showed a mean size of 176.7 ± 1.021 nm with a 0.153 polydispersibility index (PDI) value, and mangiferin encapsulation efficiency was about 55%. The optimal conditions (6000 rpm, 10 min, and 300 μg of mangiferin) obtained 77% and the highest entrapment efficiency (97%). The in vitro release profile demonstrated a gradual release of mangiferin from 15 to 180 min in acidic conditions (pH 1.5). The fingerprint showed a modification in the maximum absorption wavelength of both the polymer and the mangiferin. Results of anti-toposiomerase assay showed that the optimal formulation (MG4, 25 µg/mL) had antiproliferative activity. High concentrations (2500 µg/mL) of MG4 showed non-in vitro cytotoxic effect on BEAS 2B and HEPG2. Finally, this study showed an encapsulation process with in vitro gastric digestion resistance (1.5 h) and without interfering with the metabolism of healthy cells and their biological activity.

Abstract P1-12-16: Risk factors for trastuzumab cardiotoxicity in a cohort of Mexican population

BACKGROUND: Advances in chemotherapy and target therapy have made treatment of breast cancer (BC) more effective; however, survivors of BC suffer an increased burden of cardiotoxicity. The aim of this study is to determine the risk factors in a Mexican patients (pt)

METHODS:Observational study of a cohort of pt with locally BC and Her2 (+++) treated with trastuzumab (TZ). According to clinical stage, they underwent to surgery or neoadjuvant chemotherapy, scheme was at the decision of the physician. The main schemes: AC-T, EC-T, FAC-T, FEC-T, Paclitaxel, intravenous (IV) or subcutaneous TZ. The doses were according to NCCN guidelines and the route of administration of TZ was decision of the oncologist. Ventriculography was performed basally, at 4,8,12 cycles and at the end of treatment. If the pt presented a decrease in the ejection fraction>10% with/without symptoms, they received cardioprotection (metoprolol+atorvastatin). It was the oncologist decision to suspend chemotherapy as well as TZ.

RESULTS: 97 pt were included from Jan 2017 to Jan 2018, 35% presented cardiotoxicity. The only variables that presented a statistically significant for cardiotoxicity risk were normal weight, neoadjuvant treatment and IV TZ (table 1,2). Only 32.4% of the pt tolerated full doses of cardioprotective drugs. 13% of the pt with cardiotoxicity presented symptoms and 52.9% of the pt did not complete trastuzumab for 1year

Table 1.Demographic characteristics of the patients (n=97) TotalWith Cardiotoxicity (n=34)Without Cardiotoxicity (n=63)pAge, years. Mean (SD)50.36 (12.91)51.09 (12.46)49.97 (13.22)0.686*Body mass index, kg/m2. Median (range)37.98 (21.23 -63.0728.15 (21.23 - 43.84)41.58 (31.67 - 63.07)0.0001¥Hypertension, presence. n (%)18 (18.6)8 (23.5)10 (15.9)0.416Diabetes, presence. n (%)16 (16.5)8 (23.5)8 (12.7)0.251Smoking, presence. n (%)14 (14.4)2 (5.9)12 (19.0)0.128Weight. n (%)    Normal3 (3.1)3 (8.8)0 (0)0.0001Overweight22 (22.7)22 (64.7)0 (0) Obestity72 (74.2)9 (26.5)63 (100) Abreviation.AJCC. American Joint Committee on Cancer 2010. / *T-student, ¥U Mann-Whitney. The rest were analized with X2

Table 2.Treatment characteristics (n=97)Systemic treatment. n (%)TotalWith Cardiotoxicity (n=34)Without Cardiotoxicity (n=63)pNeoadjunvant35 (36.1)30 (88.2)5 (7.9)<0.0001Adjuvant62 (63.9)4 (11.8)58 (92.1) Chemotherapy scheme. n (%)   0.687AC-T50 (51.5)20 (58.8)30 (49.2) EC -T40 (41.2)12 (35.3)28 (45.9) FAC-T2 (2.1)1 (2.9)1 (1.6) FEC-T2 (2.1)0 (0)2 (3.2) Paclitaxel3 (3.1)1 (2.9)2 (3.2) Acumulative dose antracicline, mg. Median (range)432 (0 - 1440)420 (0-760)432 (0-1440)0.874*Trastuzumab administration way. n (%)   0.0001Subcutaneous87 (89.7)24 (70.6)63 (100) Intravenous10 (10.3)10 (29.4)0 (0) Trastuzumab cycles. Median (range)17 (3 - 17)13 (3 - 17)17 (6 - 17)0.0001*Ejection fraction left ventricle. Median (range)67.4 (38 - 75)67.2 (38 - 74)67.4 (61 -75)0.428*Abreviation: * U Mann-Whitney. The rest were analized with X2 / AC-T: Adriamicin/Cyclophosphamide - Paclitaxel, EC-T: Epirrubicin/Cyclophosphamide - Paclitaxel, FAC-T: Fluorouracil/Cyclophosphamide-Paclitaxel

DISCUSSION: This study shows that normal weight and IV TZ is significantly associated with the risk of cardiotoxicity. The observation of our pt will continue to observe this phenomenon in detail.

Citation Format: Herrera-Martínez M, Miranda-Aguirre PA, Cota-Apodaca LA, Martínez-Bustos V, Carbajal-Saldaña B, Deneken-Hernandez ZC, Díaz-Romero C, Namba-Bando MdMY, Dominguez-Reyes CA, Tenorio-Torres JA, Villegas-Carlos F, Crocco-Quiros B. Risk factors for trastuzumab cardiotoxicity in a cohort of Mexican population [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-12-16.

Structural and functional characterization of the divergent Entamoeba Src using Src inhibitor-1

Background

The abundant number of kinases that Entamoeba histolytica possesses allows us to assume that the regulation of cellular functions by phosphorylation-dephosphorylation processes is very important. However, the kinases responsible for the phosphorylation in Entamoeba spp. vary in the structure of their domains and, therefore, could be responsible for the unusual biological characteristics of this parasite. In higher eukaryotes, Src kinases share conserved structural domains and are very important in the regulation of the actin cytoskeleton. In both Entamoeba histolytica and Entamoeba invadens, the major Src kinase homologue of higher eukaryotes lacks SH3 and SH2 domains, but does have KELCH domains; the latter are part of actin cross-linking proteins in higher eukaryotic cells.

Methods

The function of the EhSrc protein kinase of Entamoeba spp. was evaluated using Src inhibitor-1, microscopy assays, Src kinase activity and western blot. In addition, to define the potential inhibitory mechanism of Src-inhibitor-1 for the amoebic EhSrc protein kinase, molecular dynamic simulations using NAnoscale Molecular Dynamics (NAMD2) program and docking studies were performed with MOE software.

Results

We demonstrate that Src inhibitor-1 is able to prevent the activity of EhSrc protein kinase, most likely by binding to the catalytic domain, which affects cell morphology via the disruption of actin cytoskeleton remodeling and the formation of phagocytic structures without an effect on cell adhesion. Furthermore, in E. invadens, Src inhibitor-1 inhibited the encystment process by blocking RhoA GTPase activity, a small GTPase protein of Rho family.

Conclusions

Even though the EhSrc molecule of Entamoeba is not a typical Src, because its divergent amino acid sequence, it is a critical factor in the biology of this parasite via the regulation of actin cytoskeleton remodeling via RhoA GTPase activation. Based on this, we conclude that EhSrc could become a target molecule for the future design of drugs that can prevent the transmission of the disease.

Electronic supplementary material

The online version of this article (10.1186/s13071-017-2461-5) contains supplementary material, which is available to authorized users.

EVALUATION OF ANTICANCER POTENTIAL OF EIGHT VEGETAL SPECIES FROM THE STATE OF OAXACA

Background:

Eight plant species from Oaxaca, some of them used in traditional medicine, were subjected to screening of several biological activities to provide data regarding their anticancer potential, although no scientific information is available about their pharmacological effects.

Materials and methods:

Methanol extracts from stems or roots of the eight plants were tested for antioxidant activity by the DPPH- method. Antimicrobial activity was determined using the agar diffusion method and the minimal inhibitory concentration (MIC) was obtained by broth dilution method. Antitopoisomerase activity was assessed using mutant strains of Saccharomyces cerevisiae JN362a, JN394, JN394t_-1, JN394t₂.₄ and JN394t_2-5. The mutagenic activity was evaluated using the Ames test (Salmonella typhimurium TA1535).

Results:

No extract showed significant antioxidant activity. The best antimicrobial activity was observed for Salpianthus arenarius (MIC 56.25 μg/mL) and Lantana achyranthifolia (MIC 78.12 μg/mL) against Staphylococcus aureus. Extracts of Acalypha cuspidata, Alloispermum integrifolium and L. achyranthifolia stems showed antitopoisomerase II activity with JN394_t-1 growth of -30.88±0.0%, -38.11±4.95%, and -70.97±12.02% respectively. Galium mexicanum stem extract showed antitopoisomerase I activity with growth of 35.31±6.36% on the same mutant strain. All plant extracts were non-mutagenic. Fractionation of A. cuspidata extract led to identification of two subfractions with antitopoisomerase I and II activity at 154μg/mL (Positive controls 50 and 100μg/mL).

Conclusion:

Methanol extracts of A. cuspidata, A. integrifolium, G. mexicanum, and L. achyranthifolia stems showed antitopoisomerase and non-mutagenic activities, and consequently could be promising as a source of anticancer drugs.

Antiamoebic Activity of Adenophyllum aurantium (L.) Strother and Its Effect on the Actin Cytoskeleton of Entamoeba histolytica

In Mexico, the Adenophyllum aurantium (L.) Strother plant is consumed as an infusion to treat intestinal diseases such as amoebiasis, which is an endemic health problem in Mexico and other countries. However, the effect of A. aurantium on Entamoeba histolytica, the causative agent of amoebiasis, is unknown. An aerial part methanolic extract (AaMeA), a root methanolic extract (AaMeR) and a root ethyl acetate extract (AaEaR) were tested on E. histolytica trophozoites. AaMeA and AaMeR did not show antiproliferative activity; however, AaEaR exhibited an in vitro GI50 of 230 μg/ml, and it was able to inhibit the differentiation of Entamoeba invadens trophozoites into cysts. The intraperitoneal administration of AaEaR (2.5 or 5 mg) to hamsters that were infected with E. histolytica inhibited the development of amoebic liver abscesses in 48.5 or 89.0% of the animals, respectively. Adhesion to fibronectin and erythrophagocytosis were 28.7 and 37.5% inhibited by AaEaR, respectively. An ultrastructure analysis of AaEaR-treated trophozoites shows a decrease in the number of vacuoles but no apparent cell damage. Moreover, this extract affected the actin cytoskeleton structuration, and it prevented the formation of contractile rings by mechanism(s) that were independent of reactive oxygen species and RhoA activation pathways. (13)C NMR data showed that the major compounds in the AaEaR extract are thiophenes. Our results suggest that AaEaR may be effective in treatments against amoebiasis, nevertheless, detailed toxicity studies on thiophenes, contained in AaEaR, are required to avoid misuse of this vegetal species.