Intramuscular compatibility of an injectable anti-inflammatory nanodispersion from a standardized Bixa orellana oil (Chronic®): a toxicological study in Wistar rats.

Bixa orellana L. is a plant popularly known as "ucurum", "annatto", and "achiote". It is native to South America, and its seeds are an abundant source of geranylgeraniol and tocotrienols. Nanoencapsulation is a valuable technique that can decrease the drug needed to achieve an effect, decreasing potential toxicity, side effects and potentiate the anti-inflammatory effect. This study aimed to evaluate the acute toxicity of an intramuscular application of a nanodispersion containing a standardized extract from the seeds of Bixa orellana (NBO) in Wistar rats. The chemical evaluation showed δ-tocotrienol at 0.725 ± 0.062 mg/mL (72.6 ± 0.9%). The stability study showed the nanoparticles had an average size from 53.15 ± 0.64 to 59.9 ± 3.63 nm, with a polydispersity index ranging from 0.574 ± 0.032 to 0.574 ± 0.32, Zeta potential from 18.26 ± 0.59 to 19.66 ± 1.45 mV. After testing the intramuscular application of NBO with doses from 1 to 5 mg/kg in animals, it was observed that the acute treatment did not elicit any toxic effects within this range. The dose of 10 mg/kg, although not affecting hematological and biochemical parameters (CPK, LDH, myoglobin, AST, ALT, TC, TG, glucose levels, creatinine, and urea), could induce some muscle tissue changes, including leukocyte infiltration, morphological chances, and potentially necrosis. In conclusion, the results showed that the treatments devoided toxicity between 1 and 5 mg/kg.

Potential of the Compounds from Bixa orellana Purified Annatto Oil and Its Granules (Chronic®) against Dyslipidemia and Inflammatory Diseases: In Silico Studies with Geranylgeraniol and Tocotrienols.

Some significant compounds present in annatto are geranylgeraniol and tocotrienols. These compounds have beneficial effects against hyperlipidemia and chronic diseases, where oxidative stress and inflammation are present, but the exact mechanism of action of such activities is still a subject of research. This study aimed to evaluate possible mechanisms of action that could be underlying the activities of these molecules. For this, in silico approaches such as ligand topology (PASS and SEA servers) and molecular docking with the software GOLD were used. Additionally, we screened some pharmacokinetic and toxicological parameters using the servers PreADMET, SwissADME, and ProTox-II. The results corroborate the antidyslipidemia and anti-inflammatory activities of geranylgeraniol and tocotrienols. Notably, some new mechanisms of action were predicted to be potentially underlying the activities of these compounds, including inhibition of squalene monooxygenase, lanosterol synthase, and phospholipase A2. These results give new insight into new mechanisms of action involved in these molecules from annatto and Chronic®.