Leaf Extract of Eugenia uniflora L. Prevents Episodic Memory Impairment Induced by Streptozotocin in Rats

Abstract

Background: Eugenia uniflora is a plant found in several countries of South America and is traditionally used in folk medicine as an antimicrobial, anti‑inflammatory, and antihypertensive agent.Objective: This study aimed to investigate the neuroprotective effect of the ethanolic extract of E. uniflora leaves on memory impairment induced by streptozotocin (STZ) in rats.Materials and Methods: The ethanolic extract of E. uniflora leaves was used to treat Wistar rats which received intracerebroventricular (ICV)‑STZ. Animals were allocated to the control group (n = 10), i.e., ICV vehicle solution + ethanol 10%; STZ group (n = 10), i.e., ICV‑STZ + ethanol 10%; STZ + E. uniflora (300 mg/kg) group (n = 10), i.e., ICV‑STZ +300 mg/kg of leaf extract of E. uniflora; and STZ + E. uniflora (1000 mg/kg) group (n = 10), i.e., ICV‑STZ +1000 mg/kg of leaf extract of E. uniflora. The animals were submitted to the treatments 24 h after receiving ICV‑STZ. The treatments were performed on alternate days over a 30‑day period. After this period, the animals were tested in the elevated plus maze to assess learning and memory.Results: The STZ group presented a higher transfer latency (P 0.05) for both the doses.Conclusion: The leaf extract of E. uniflora showed a neuroprotective effect on memory impairment induced by STZ in rats.

Keywords: Elevated plus maze; Episodic memory; Eugenia uniflora; Neuroprotection; Streptozotocin.