Atividade do Óleo de Pequi (Caryocar brasiliense Cambess.) no Tratamento de Infecção do Trato Urinário em Modelo Experimental de Bexiga Neurogênica em Ratos

Abstract

Urinary tract infections (UTIs) associated with neurogenic bladder represent a significant clinical challenge, particularly due to urinary stasis, persistent bacterial colonization, and increasing antimicrobial resistance. In this context, natural bioactive compounds have been investigated as complementary therapeutic alternatives. This study aimed to evaluate the therapeutic potential of Caryocar brasiliense Cambess. oil in an experimental model of neurogenic bladder associated with urinary tract infection, integrating both in vitro and in vivo analyses. For this purpose, a complete spinal cord transection model was performed in Wistar rats, followed by induction of urinary infection using isolated uropathogenic microorganisms. In the in vivo assay, the animals were allocated into five experimental groups (n = 5/group): negative control (untreated), positive control (antibiotic therapy), and three groups treated with pequi oil at doses of 500, 1,000, and 2,000 mg/kg, administered by gavage every 12 hours. Evaluations were conducted at experimental time points of 4 and 8 days, including microbiological analysis (CFU/mL), urinalysis, hematological parameters, and histopathological assessment. The results demonstrated that the experimental model was effective, with an initial bacterial load exceeding 10⁵ CFU/mL, along with the presence of hematuria and motor deficits. In the negative control group, infection progression was observed, with a mean bacterial load of 5 × 10⁶ CFU/mL on day 4 and 100% mortality by day 8. The group treated with 500 mg/kg showed no significant reduction in bacterial load, with values ranging from 1.2 × 10⁶ to 1.4 × 10⁶ CFU/mL. In contrast, the doses of 1,000 and 2,000 mg/kg demonstrated a dose-dependent effect, with bacterial load reductions from 9 × 10⁵ to 6 × 10⁵ CFU/mL and from 6 × 10⁵ to 4 × 10⁵ CFU/mL, respectively, between days 4 and 8. The positive control group showed a more pronounced response, achieving complete bacterial clearance by day 8. Urinalysis revealed a progressive reduction in hematuria, leukocyturia, and bacteriuria in the higher-dose groups, associated with improvement in physicochemical urinary parameters. Additionally, hematological and histopathological findings indicated preservation of renal and hepatic integrity, suggesting low toxicity of the oil. In the in vitro assay, no measurable direct antimicrobial activity was observed, which was attributed to the limited solubility of the oil in aqueous media. It is concluded that, although no direct antimicrobial effect was observed under the tested conditions, Caryocar brasiliense Cambess. oil demonstrated relevant therapeutic potential in vivo, with a dose-dependent reduction in bacterial load and modulation of the inflammatory process, representing a promising complementary strategy in the management of urinary infections associated with neurogenic conditions.