Publications by authors named "Mario Steindel"

Chemical studies of twigs yielded two compounds, identified as taraxerol () and methyl gallate (). The galloyl moiety was suggested as a potential scaffold that can interfere with proteases by previous biological investigations on SARS-CoV-2 main protease (M) inhibitors in combination with docking studies. Therefore, a series of 13 gallate esters were prepared by treating gallic acid with natural and non-natural alcohols.

View Article and Find Full Text PDF

The present work reports the inhibitory effect of amides derived from gallic acid (gallamides) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease (M), along with cytotoxicity evaluation and molecular docking studies. In addition to gallamides, other relevant compounds were also synthesized and evaluated against M, making a total of 25 compounds. Eight compounds presented solubility issues during the inhibitory assay and one showed no inhibitory activity.

View Article and Find Full Text PDF

Natural pigments have received special attention from the market and industry as they could overcome the harm to health and the environmental issues caused by synthetic pigments. These pigments are commonly extracted from a wide range of organisms, and when added to products they can alter/add new physical-chemical or biological properties to them. Fungi from extreme environments showed to be a promising source in the search for biomolecules with antimicrobial and antiparasitic potential.

View Article and Find Full Text PDF

The mangrove ecosystem plays a crucial role in preserving the biodiversity of plants, animals, and microorganisms that are essential for materials cycles. However, the exploration of endophytic fungi isolated from mangroves, particulary in Santa Catarina (SC, Brazil), remains limited. Therefore, the purpose of this study was to assess the biodiversity of endophytic fungi found in Avicennia schaueriana, Laguncularia racemosa, Rhizophora mangle, and Spartina alterniflora from two mangroves on the Island of Santa Catarina: one impacted by anthropic action (Itacorubi mangrove) and the other environmentally preserved (Ratones mangrove).

View Article and Find Full Text PDF

The discovery of biomolecules has been the subject of extensive research for several years due to their potential to combat harmful pathogens that can lead to environmental contamination and infections in both humans and animals. This study aimed to identify the chemical profile of endophytic fungi, namely and , which were isolated from and . We identified several HPLC-MS compounds, including Ethylidene-3,39-biplumbagin, Pestauvicolactone A, Phenylalanine, 2-Isopropylmalic acid, Fusaproliferin, Sespendole, Ansellone, Calanone derivative, Terpestacin, and others.

View Article and Find Full Text PDF

SARS-CoV-2 main protease (M ) plays an essential role in proteolysis cleavage that promotes coronavirus replication. Thus, attenuating the activity of this enzyme represents a strategy to develop antiviral agents. We report inhibitory effects against M of 40 synthetic chalcones, and cytotoxicity activities, hemolysis, and in silico interactions of active compounds.

View Article and Find Full Text PDF

Chemical scaffolds of natural products have historically been sources of inspiration for the development of novel molecules of biological relevance, including hit and lead compounds. To identify new compounds active against Trypanosoma cruzi, we designed and synthesized 46 synthetic derivatives based on the structure of two classes of natural products: tetrahydrofuran lignans (Series 1) and oxazole alkaloids (Series 2). Compounds were screened in vitro using a cellular model of T.

View Article and Find Full Text PDF

Mangroves are ecosystems with unique characteristics due to the high salinity and amount of organic matter that house a rich biodiversity. Fungi have aroused much interest as they are an important natural source for the discovery of new bioactive compounds, with potential biotechnological and pharmacological interest. This review aims to highlight endophytic fungi isolated from mangrove plant species and the isolated bioactive compounds and their bioactivity against protozoa, bacteria and pathogenic viruses.

View Article and Find Full Text PDF

Human trypanosomiases and animal trypanosomoses are caused by distinct protozoan parasites of the genus Trypanosoma. The etiological agents of bovine trypanosomosis (BT) are T. vivax, T.

View Article and Find Full Text PDF

Cutaneous leishmaniasis is a worldwide public health problem. Conventional therapies, in addition to the high cost, have many adverse effects and cases of parasite's resistance. Chalcones are secondary metabolites precursors in the flavonoid pathway and can be obtained naturally, but with low yield from plant raw material.

View Article and Find Full Text PDF

The drugs currently used to treat leishmaniases have limitations concerning cost, efficacy, and safety, making the search for new therapeutic approaches urgent. We found that the gold(I)-derived complexes were active against and intracellular amastigotes with IC values ranging from 0.5 to 5.

View Article and Find Full Text PDF

Banana inflorescences are a byproduct of banana cultivation consumed in various regions of Brazil as a non-conventional food. This byproduct represents an alternative food supply that can contribute to the resolution of nutritional problems and hunger. This product is also used in Asia as a traditional remedy for the treatment of various illnesses such as bronchitis and dysentery.

View Article and Find Full Text PDF

Serodiagnosis of infection in dogs relies on the detection of antibodies against leishmanial crude extracts or parasitic defined antigens. The expansion of canine leishmaniasis from geographical areas of Brazil in which the infection is endemic to regions in which the disease is emerging is occurring. This fact makes necessary the analysis of the serodiagnostic capabilities of different leishmanial preparations in distinct geographical locations.

View Article and Find Full Text PDF

Aristolochia triangularis Cham., is one of the most frequently used medicinal plant in Southern Brazil. Preparations containing the leaves and/or stems are traditionally used as anti-inflammatory, diuretic, as well as antidote against snakebites.

View Article and Find Full Text PDF

Background: Chagas disease is a potentially life-threatening disease caused by the protozoan parasite Trypanosoma cruzi. Current therapeutic management is limited to treatment with nitroheterocyclic drugs, such as nifurtimox (NFX) and benznidazole (BZ). Thus, the identification of affordable and readily available drugs to treat resistant parasites is urgently required worldwide.

View Article and Find Full Text PDF

The study aims to evaluate the antiprotozoal activities of 20 plant metabolites on Trypanosoma cruzi and Leishmania amazonensis amastigotes. Compounds 1-20 were obtained and identified by using chromatographic and spectroscopic techniques. The antiparasitic assays were performed on the intracellular form of T.

View Article and Find Full Text PDF

The current paucity of effective and affordable drugs for the treatment of leishmaniasis renders the search for new therapeutic alternatives a priority. Gallic acid-related compounds display anti-parasitic activities and their incorporation into drug carrier systems, such as polymeric nanoparticles may be a viable alternative for leishmaniasis treatment. Therefore, this study focused on the synthesis and characterization of octyl gallate (G8) loaded poly(methyl methacrylate) (PMMA) nanoparticles via miniemulsion polymerization in order to increase the leishmanicidal activity of this compound.

View Article and Find Full Text PDF

In this study we report the synthesis, characterization, biological evaluation, and druglikeness assessment of a series of 20 novel isoxazolyl-sulfonamides, obtained by a four-step synthetic route. The compounds had their activity against Trypanosoma cruzi, Leishmania amazonensis, Herpes Simplex Virus type 1 and cytotoxicity evaluated in phenotypic assays. All compounds have drug-like properties, showed low cytotoxicity and were promising regarding all other biological activities reported herein, especially the inhibitory activity against T.

View Article and Find Full Text PDF

Despite the impressive scientific and technological advances of recent decades, no effective treatment is currently available for Chagas disease. Our research group has been studying the design and synthesis of analogues of natural lignans aiming to identify compounds with antiparasitic activity. This article reports the synthesis of 42 novel bis-heterocyclic derivatives and the structure-activity relationship study conducted based on results of biological assays against Trypanosoma cruzi amastigotes.

View Article and Find Full Text PDF

Mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) is characterized by its well-defined clinical profile. Limbic encephalitis is increasingly recognized as a possible etiology of adult-onset MTLE-HS, and neuronal autoantibodies have been detected in patients even without previous signs of encephalitis. The aim of this study is to analyze the frequency of specific autoantibodies in patients with MTLE-HS.

View Article and Find Full Text PDF

Different studies reported that genetic predisposition or metabolic dysfunction are the risk factors for cancer. Infectious parasitic diseases were listed among factors that predispose to cancer. Because of the resemblance between the life cycle of cancer cells and some parasites, this study aimed to prepare pyran derivatives with cytotoxic and antiprotozoal potencies.

View Article and Find Full Text PDF

Objective: To determine the course of serological tests in subjects with chronic Trypanosoma cruzi infection treated with anti-trypanosomal drugs.

Methods: A systematic review and meta-analysis was conducted using individual participant data. Survival analysis and the Cox proportional hazards regression model with random effects to adjust for covariates were applied.

View Article and Find Full Text PDF

Mixed infections with Trypanosoma cruzi and Trypanosoma rangeli and their different genetic groups occur frequently in vertebrate hosts and are difficult to detect by serology. In the present study, we evaluated the limit of detection of polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) analysis of cytochrome oxidase II (COII) for the identification of genetic groups of these two parasites in blood and tissue from vertebrate hosts. Reconstitution experiments were performed using human blood (TcI/TcII and KP1+/KP1-) and mouse tissue (TcI/TcII).

View Article and Find Full Text PDF

Introduction: The resin of Cola nitida is used in western Cameroon as incense for spiritual protection and during ritual ceremonies. This plant secretion has never been investigated although previous chemical and biological studies on other resins have drawn many attentions.

Objective: The resin fractions which revealed inhibitory effect on nitric oxide (NO) and tumour necrosis factor alpha (TNF-α) released by lipopolysaccharide (LPS)-activated J774 macrophage as well as on intracellular forms of Leishmania amazonensis and Trypanosoma cruzi amastigote were chemically characterised.

View Article and Find Full Text PDF