Genotoxicity and mutagenicity of Echinodorus macrophyllus (chapéu-de-couro) extracts

Mutagenic potential of medicinal plants evaluated by the Ames Salmonella/microsome assay: A systematic review

The Ames test has become one of the most commonly used tests to assess the mutagenic potential of medicinal plants since they have several biological activities and thus have been used in traditional medicine and in the pharmaceutical industry as a source of raw materials. Accordingly, this review aims to report previous use of the Ames test to evaluate the mutagenic potential of medicinal plants. A database was constructed by curating literature identified by a search on the electronic databases Medline (via Pubmed), Science Direct, Scopus, and Web of Science from 1975 to April 2020, using the following terms: "genotoxicity tests" OR "mutagenicity tests" OR "Ames test" AND "medicinal plants." From the research, 239 articles were selected, including studies of 478 species distributed across 111 botanical families, with Fabaceae, Asteraceae and Lamiaceae being the most frequent. It was identified that 388 species were non-mutagenic. Of these, 21% (83/388) showed antimutagenic potential, most notable in the Lamiaceae family. The results also indicate that 18% (90/478) of the species were mutagenic, of which 54% were mutagenic in the presence and absence of S9. Strains TA98 and TA100 showed a sensitivity of 93% in detecting plant extracts with mutagenic potential. However, the reliability of many reviewed studies regarding the botanical extracts may be questioned due to technical issues, such as testing being performed only in the presence or absence of S9, use of maximum doses below 5 mg/plate and lack of information on the cytotoxicity of tested doses. These methodological aspects additionally demonstrated that a discussion about the doses used in research on mixtures, such as the ones assessed with botanical extracts and the most sensitive strains employed to detect the mutagenic potential, should be included in a possible update of the guidelines designed by the regulatory agencies.

Flavonoid-enriched fraction from Echinodorus macrophyllus aqueous extract exhibits high in-vitro and in-vivo anti-inflammatory activity

Objectives

Echinodorus macrophyllus (Kunth) Micheli (Alismataceae) is popularly used as an infusion to treat inflammatory diseases. This work fractionated the aqueous extract of E. macrophyllus (AEEm) to improve its anti-inflammatory effects.

Methods

Aqueous extract of E. macrophyllus was fractionated by Sephadex LH-20 and analysed by HPLC-DAD. Anti-inflammatory action was evaluated, in vivo, by air pouch model (total leucocyte, protein and leukotriene B4 (LTB4)), and, in vitro, by neutrophil migration (transwell assay) and its Mac1 expression (flow cytometry), and RAW 264.7 nitric oxide (NO) production (Griess reaction).

Key findings

Fr20 reduced total leucocyte at 2.5 mg/kg (29.7%) while ethanolic extract of E. macrophyllus (EAEm) increased it (94.0%). Fr20 showed higher (P < 0.05) inhibition (89.8%) of LTB4 in exudate than EAEm (75.0%). Fr20 and EAEm decreased exudate protein and inflammatory infiltrate in pouch tissues, in-vitro neutrophil migration, and NO production. Otherwise, Fr40 did not reduce leucocytes and exudate protein (until 50 mg/kg) nor tissue inflammation, and increased in-vitro NO production. The inhibition of neutrophil migration by EAEm, but not Fr20, was dependent on reduced Mac-1 expression.

Conclusions

The fractionation of AEEm provided a more potent anti-inflammatory fraction containing flavonoids (Fr20) that reduces the migration of neutrophils and LTB4 release, probably contributing to its mechanism of action.

Genotoxic Maillard byproducts in current phytopharmaceutical preparations of Echinodorus grandiflorus

Extracts of Echinodorus grandiflorus obtained from dried leaves by three different techniques were evaluated by bacterial lysogenic induction assay (Inductest) in relation to their genotoxic properties. Before being added to test cultures, extracts were sterilized either by steam sterilization or ultraviolet light. Only the extracts prepared by infusion and steam sterilized have shown genotoxic activity. The phytochemical analysis revealed the presence of the flavonoids isovitexin, isoorientin, swertisin and swertiajaponin, isolated from a genotoxic fraction. They were assayed separately and tested negative in the Inductest protocol. The development of browning color and sweet smell in extracts submitted to heat, prompted further chemical analysis in search for Maillard's reaction precursors. Several aminoacids and reducing sugars were cast in the extract. The presence of characteristic Maillard's melanoidins products was determined by spectrophotometry in the visible region and the inhibition of this reaction was observed when its characteristic inhibitor, sodium bisulfite, was added prior to heating. Remarkably, this is the first paper reporting on the appearance of such compounds in a phytomedicine preparation under a current phytopharmaceutical procedure. The genotoxic activity of such heat-prepared infusions imply in some risk of developing degenerative diseases for patients in long-term, uncontrolled use of such phytomedicines.

Renoprotective effect of the Echinodorus macrophyllus in induced renal injury

OBJECTIVE: Evaluating the renoprotective effect of Echinodorus macrophyllusin acute kidney injury induced by cyclophosphamide in rats.METHODS: Experimental research with Wistar rats, male adults, distributed into groups, namely: Control - administration of 1.5 ml sodium chloride 0.9% intraperitoneally; Echinodorous - administration of 2g/kg of Echinodorus macrophyllus by gavage for five days; Cyclophosphamide - administration of cyclophosphamide 150mg/kg intraperitoneally; and Cyclosphosphamide + Echinodorus - administration of Echinodorus macrophyllus and cyclophosphamide. Renal function (creatinine clearance) and the oxidative metabolites (peroxides and urinary substances reactive to thiobarbituric acid, thiols in kidney tissue) were evaluated.RESULTS: Preconditioning with Echinodorus macrophyllus elevated the creatinine clearance and reduced the levels of oxidative metabolites.CONCLUSION: The antioxidant action of Echinodorus macrophyllus has demonstrated renoprotective effects evidenced by the reduction of oxidative stress in acute renal injury induced by cyclophosphamide in rats.

Determination and evaluation of the metals and metalloids in the Chapeu-de-couro (Echinodorus macrophyllus (Kunth) Micheli)

The Chapeu-de-couro (Echinodorus macrophyllus (Kunth) Micheli) is a native plant from Brazil, which has been mainly used in medicinal application being a potent antirheumatic and diuretic, in the production of soft drinks, and also in the ornamentation of aquariums. In this paper, the metals and metalloids for the leaves of chapeu-de-couro collected in the Paraguacu River from the city Cachoeira, Bahia State, Brazil, was determined and evaluated using multivariate analysis. The samples were digested using nitric acid and hydrogen peroxide and were analyzed using inductively coupled plasma mass spectrometry. The accuracy of the method was confirmed by analysis of a certified reference material of apple leaves, furnished by National Institute of Standard and Technology. The study involved 15 samples of the Paraguacu River. The results expressed as milligrams of element per kilogram of sample demonstrated that the concentration ranges varied: 1.39-5.27 for chromium, 44.85-165.39 for manganese, 0.55-0.84 for arsenic, 0.01-3.94 for antimony, and 0.18-0.31 for lead. The principal component analysis and hierarchical cluster analysis evidenced that the concentrations of the metals and metalloids varied according with the variations in the water of the Paraguacu.