Effect of a hydro-alcoholic extract of Melissa officinalis on passive avoidance learning and memory

Abstract

The results of this study revealed that Melissa officinalis can enhance learning and memory in the passive avoidance test. The high levels of phenols and flavonoids in M. officinalis extracts may be responsible for its beneficial effects.Introduction: Melissa officinalis (MO) or lemon balm is traditionally used as a sedative and anti-spasm herbal medicine. There is also evidence that this plant has effects on learning and memory. This study examined the effect of a hydro-alcoholic extract of MO on passive avoidance learning (PAL) and memory in male rats. Methods: A total of 40 adult male Wistar rats were randomly distributed into four groups (200 to 220 g; n = 10 per group); three dose groups (50, 100, and 200 mg/kg of the hydro-alcoholic extract of MO) and vehicle control (saline) group. Saline or doses of extract were administered daily for 14 days by oral gavage. The rats were trained to enter the shuttle box to record their behavior in the PAL task. A retrieval test was performed 24 hours following training. Results: A significant difference was seen in performance among MO groups and the control. MO administered animals had a decreased number of acquisition trials (P < 0.05). In the retention task, MO administered animals had an increased step-through latency (SLT) (P < 0.01), and a decreased latency in the dark compartment (P < 0.001) compared to the control group. Conclusion: The results of the study show that MO can improve learning and memory in the PAL task. Further investigation is needed to enhance our understanding of the neurobiological mechanisms of the MO extract and its effects on learning and memory.

Identification of New Alkaloids from Algerian Purslane by HPLC-QTOF-MS and Beneficial Effect of Purslane Enriched with Zinc on Experimental Alzheimer Disease in Rats

“…Subsequently, 60 seconds later the rat was delivered to the cage. In the next day of training if, the animal didn't enter the dark in 120 seconds, a successful acquisition of a passive avoidance behavior (14).…”

“…Step-through latency; STL (the latency to enter the dark side) and time spent in the dark chamber (TDC) were reported for up to 120 seconds if the rodent last in the light compartment in 120 second, the retention test was ended, and the maximum score of 120 seconds was reported (14).…”

Phytochemical composition of wild lemon balm (Melissa officinalis L.) from the flora of Bulgaria

“…The flavonoids contained in the composition (quercetin, luteolin, rhamnocitrin, and others) increased the application of the species in medicine. High levels of polyphenols improved the memory (Dehbani et al, 2019) and mood (Kennedy et al, 2002) of the people, and were used in the therapy of some digestive and gastrointestinal disorders.…”

Melissa officinalis: a memory enhancer remedy

“…Melissa officinalis L. (MO), also known as lemon balm, is used in traditional medicine for its effects on central nervous system (CNS) functions (Shakeri et al, 2016) such as sedation (Ghazizadeh et al, 2020) and memory-enhancement (Dehbani et al, 2019).…”