Abstract:
Aim: This study aimed to investigate the impact of orlistat on spatial memory, recognition memory and hippocampal tissue in experimentally induced obesity in rats.
Method: Twenty-four 200-250 gr weighed rats were fed with high-fat diet for 15 weeks for induced obesity. They were divided into three groups as control (C), obese (O), and obese+orlistat (ORL). After the obesity, while the C and O group received the tap water, the ORL group received 10 mg/kg ORL during 7 weeks. At the last week, rats were subjected to novel object recognition (NOR) and Morris water maze (MWM) tests. At the end of the experiment, animals sacrified and TNF-alpa and IL1-beta in hippocampal tissue was measured.
Results: The orlistat group had significantly lower body weight compared to the obese group (p<0.05). According NOR, in the ORL group, a significant increase in the percentage of interest was observed compared to the obese group (p=0.01). In the Morris water maze test, the obese group exhibited increased latency in finding the platform from 2nd to 4th days compared to the control group (p<0.05). In contrast, the orlistat-treated group showed significantly decreased latency, approaching values similar to those of the control group (p<0.05). The obese group demonstrated a decrease in the time spent in the platform zone compared to the control group, while the ORL-treated group exhibited an increase in the time spent to control group (p<0.05). The TNF-alpha level exhibited a significant increase in the obese group compared to the control group (p=0.002), whereas a significant decrease in the ORL group compared to the obese group (p=0.002). IL-1 beta level showed a significant reduction in the ORL group compared to the obese group (p=0.024). According to the correlation between the results of the spatial learning and memory test and the levels of TNF-alpha and IL-1 beta in the hippocampus, only a significant negative correlation was identified between TNF-alpha and NOR (p=0.003; r= -0.637). Conclusion: Our study demonstrates that orlistat administration exerts beneficial effects on spatial learning and hippocampal tissue in experimentally induced obesity in rats. These findings suggest that orlistat may have potential therapeutic implications for obesity-related cognitive impairments and hippocampal dysfunction.
1. In addition to its weight-reducing effect,
• Orlistat has been shown to have a protective effect on spatial learning and memory.
• Furthermore, it has been found to anti-inflammatory effect when evaluating the levels of TNF-alpha and IL-1 beta in the hippocampus.
2. Due to its positive impact on cognitive functions, orlistat may be considered a preferred choice in clinical practice compared to other anti-obesity medications.
• Further clinical studies are needed in this field to clarify the effects observed in our study related to orlistat usage.
• It is important to provide detailed education on the use and effects of anti-obesity drugs in both clinical and basic sciences within medical faculties.
