Abstract Obesity and dyslipidemia are conditions often associated with cardiovascular risk, inflammation, oxidative stress, and death. Thus, a new approach has been highlighted to promote research and development of pharmacological tools derived from natural sources. Among the most widely studied groups of substances, polyphenols such as tyramine stand out. This study investigated hypolipidemic and anti-obesity properties of tyramine. Oral toxicity evaluation, models of dyslipidemia and obesity were used. To induce dyslipidemia, Poloxamer-407 (P-407) was administered intraperitoneally. In the hypercholesterolemic and obesity model, specific diet and oral tyramine were provided. After 24h of P-407 administration, tyramine 2 mg/kg (T2) decreased triglycerides (TG) (2057.0 ± 158.5 mg/dL vs. 2838 ± 168.3 mg/dL). After 48h, TG were decreased by T2 (453.0 ± 35.47 vs. 760.2 ± 41.86 mg/dL) and 4 mg/kg (T4) (605.8 ± 26.61 760.2 ± 41.86 mg/dL). T2 reduced total cholesterol (TC) after 24h (309.0 ± 11.17 mg/dL vs. 399.7 ± 15.7 mg/dL); After 48h, 1 mg/kg (T1) (220.5 ± 12.78 mg/dL), T2 (205.8 ± 7.1 mg/dL) and T4 (216.8 ± 12.79 mg/dL), compared to P-407 (275.5 ± 12.1 mg/dL). The treatment decreased thiobarbituric acid reactive substances and nitrite in liver, increased superoxide dismutase, reduced the diet-induced dyslipidemia, decreasing TC around 15%. Tyramine reduced body mass, glucose, and TC after hypercaloric feed. Treatment with 5 mg/L (0.46 ± 0.04 ng/dL) and 10 mg/L (0.44 ± 0.02 ng/dL) reduced plasma insulin (1.18 ± 0.23 ng/dL). Tyramine increased adiponectin at 5 mg/L (1.02 ± 0.02 vs. 0.83 ± 0.02 ng/mL) and 10mg/L (0.96 ± 0.04 ng/mL). In conclusion, tyramine has low toxicity in rodents, has antioxidant effect, reduces plasma triglycerides and cholesterol levels. However, further studies should be conducted in rodents and non-rodents to better understand the pharmacodynamic and pharmacokinetic properties of tyramine.

Dois α-aminoácidos lipídicos 1a e 1b foram isolados do zoantídeo Protopalythoa variabilis através de fracionamento guiado pela atividade citotóxica. As estruturas foram determinadas por diferentes métodos espectroscópicos, tais como, RMN (ressonância magnética nuclear) ¹H e 13C, IV (infravermelho) e espectrometria de massa de alta resolução (modo positivo). A atividade citotóxica dos extratos, das frações e 1a/1b foi avaliada in vitro através do teste do MTT contra quatro linhagens de células tumorais. Este achado tem implicações biológicas e químicas importantes para essa classe de compostos. Este é o primeiro relato de α-aminoácidos lipídicos a partir de uma fonte natural, bem como de sua atividade citotóxica.

Two lipidic α-amino acids 1a and 1b were isolated from the zoanthid Protopalythoa variabilis using a bioguided fractionation for cytotoxic activity. The structures of the metabolites were determined by spectroscopic methods, including NMR (nuclear magnetic resonance) ¹H e 13C, IR (infrared) and high resolution mass spectrometry (positive mode). The cytotoxic activity of the crude extract, as well as of the mixture of 1a and 1b were measured in vitro using the MTT assay for four human tumor cell lines. This finding has important biological and chemical implications for this type of compound. This is the first report of lipidic α-amino acids from natural sources, as well as of their cytotoxic activity.

The essential oils from leaves, root bark and root wood of Cochlospermum vitifolium were investigated for the first time. The oils were obtained by hydrodistillation and analyzed by GC/MS. The main volatile constituents were beta-caryophyllene (8.2 - 46.5%), beta-bisabolene (11.5 - 29.3%), gamma-muurolene (28.4%), alpha-humulene (26.0%), 1-hydroxy-3-hexadecanone (16.2 - 19.5%) and beta-pinene (10.6%). Phytochemical analysis of the root bark and root wood extracts yielded excelsin, pinoresinol, narigenin, aromadendrin, galic acid and a triacylbenzene, along with beta-sitosterol and stigmasterol and their D-glucosides. The structures of all compounds were determined by analyses of the spectroscopic data (NMR and MS), and comparison with the literature.

Phytochemical investigation of the resin, fruits, leaves, and trunk of Protium heptaphyllum led to the isolation of the monoterpene p-menth-3-ene-1,2,8-triol, alpha and beta amyrin, quercetin, brein, quercetin-3-O-rhamnosyl, (-) catechin and scopoletin. Their structures were established by 1D and 2D NMR spectroscopy and comparison with published data.