Efeitos do extrato de Eragrostis plana NEES e Tabernaemontana catharinensis A DC, frente a microrganismos, células de sangue periférico humano e animais com implantação tumoral - uma abordagem in vitro e in vivo

Abstract

The use of plants with pharmacological potential has been recognized since the beginning of our existence, and elucidating the activity of their phytochemical constituents continues to be a very current topic. Considering that many pathogens are resistant to drugs used as the first treatment option and that also cause toxicity to the body, the search is for new efficient treatments that have low toxicity. Natural compounds that have the potential to act as antioxidants, antimicrobials, anti-inflammatory, and/or antitumor drugs are the big bet in the field of pharmacotherapy. Eragrostis plana NEES, known as "capim annoni," is a grass from the Poaceae family, accidentally brought to Brazil, which became a pest due to its phytotoxic (allelopathic) potential. Efforts are focused on controlling the species' spread on Rio Grande do Sul soil. Allelopathy is associated with compounds from the plant's primary and secondary metabolism, such as phenolics, present in almost all plant species, which protect the plant from phytopathogens. Numerous plants with these compounds have had their antioxidant, bactericidal, and fungicidal potentials proven through in vitro and in vivo tests. Tabernaemontana catharinensis A DC (Apocynaceae) is a native plant in Rio Grande do Sul, with bark and leaves used in folk medicine as anti-inflammatory and antinociceptive. The present study aims to elucidate the phytochemical constitution, antimicrobial, and antitumor potential of the crude methanolic extracts of these two plants. The in vitro tests included exposure to Gram-negative and Gram-positive bacterial strains, human peripheral blood mononuclear cells (PBMCs), and a colon cancer tumor line (CT26). In vivo, the antitumor potential was evaluated in animals implanted with colon tumors, as well as the hepatotoxic and nephrotoxic effects and the expression of apoptotic genes in tumor tissue. The results support the potential of both plant species for developing new pharmacological approaches.