Intermittent Fasting Ameliorated High-Fat Diet-Induced Memory Impairment in Rats via Reducing Oxidative Stress and Glial Fibrillary Acidic Protein Expression in Brain

Abstract

Intermittent fasting (IF) plays an important role in the protection against metabolic syndrome-induced memory defects. This study aimed to assess the protective effects of both prophylactic and curative IF against high-fat diet (HFD)-induced memory defects in rats. The control group received a normal diet; the second group received a HFD; the third group was fed a HFD for 12 weeks and subjected to IF during the last four weeks (curative IF); the fourth group was fed a HFD and subjected to IF simultaneously (prophylactic IF). A high-fat diet significantly increased body weight, serum lipids levels, malondialdehyde (MDA) concentration, glial fibrillary acidic protein (GFAP) and H score in brain tissue and altered memory performance. In addition, it significantly decreased reduced glutathione (GSH) concentration in brain tissue and viability and thickness of pyramidal and hippocampus granular cell layers. However, both types of IF significantly decreased body weight, serum lipids, GFAP protein expression and H score and MDA concentration in brain tissue, and improved memory performance, while it significantly increased GSH concentration in brain tissue, viability, and thickness of pyramidal and granular cell layers of the hippocampus. This study indicated that IF ameliorated HFD-induced memory disturbance and brain tissue damage and the prophylactic IF was more potent than curative IF.

Potential role for vitamin D vs. intermittent fasting in controlling aquaporin-1 and aquaporin-3 expression in HFD-induced urinary bladder alterations in rats

“…Furthermore, our study found that rats subjected to IF had significantly lower serum levels of TG, LDL, and cholesterol as well as significantly greater serum levels of HDL contrasted with the HFD group. These results corroborated those of Hazzaa et al (2020) , who described these adjustments as being caused by the hypothesis that caloric restriction can improve lipid profile parameters by raising the activity of lipoprotein lipase (LPL), which in turn promotes triglyceride clearance in blood vessels. The activated LPL also speeds up the breakdown of triglyceride-rich lipoproteins, transferring esters, apoproteins, and phospholipids to produce HDL ( Chen et al, 2015 ).…”

“…This outcome was consistent with the findings of Lee et al (2006) , who claimed that caloric restriction significantly decreased the production of ROS and the consumption of cellular oxygen in the mitochondria of rat muscle. Additionally, fasting significantly reduced the amount of oxidative DNA damage ( Hazzaa et al, 2020 ). Furthermore, it was noted by Gnoni et al (2021) that IF decreased the amount of messenger ribonucleic acid (mRNA) that encodes iNOS in the rat hippocampus.…”

Intermittent fasting reduces alpha-synuclein pathology and functional decline in mice

“…The pro-inflammatory M1 microglia use mainly glycolysis, while the anti-inflammatory M2 microglia utilize rather fatty acids and oxidative metabolism to produce energy (Orihuela et al, 2016). Thus, manipulating metabolic reprogramming may facilitate microglia polarization and reduce pathological inflammatory responses in neurodegenerative diseases (Hazzaa et al, 2021;Vasconcelos et al, 2014;Yang et al, 2021). Indeed, IF has been shown previously to reduce microglial production of TNFα and IL-1β, and to increase the number of M2 microglia in a mouse model of intracerebral hemorrhage (Dai et al, 2022).…”

“…By increasing the levels and activity of antioxidant enzymes, IF further reduces oxidative damage (Martinez-Lopez et al, 2017). In the brain, IF increases the synthesis of neuroprotective factors such as brain derived neurotrophic factor (BDNF) and insulin-like growth factor 1 (IGF1) (Elesawy et al, 2021;Guerra-Cantera et al, 2020;Seidler and Barrow, 2021), and reduces neuroinflammation (Hazzaa et al, 2021;Vasconcelos et al, 2014). Several effects of IF, including signaling to BDNF and mTOR, can be attributed to the ketone body βhydroxybutyrate (BHB) (Carretta et al, 2020;Giacco et al, 2022;Newman and Verdin, 2014;Rahman et al, 2014), which is produced mainly in the liver during energy demand (Achanta and Rae, 2016;Hasselbalch et al, 1995).…”

Intermittent fasting and mental and physical fatigue in obese and non-obese rats

“…This study utilized a DIO model to examine whether IF would result in mental and physical fatigue in obese and non-obese rats. It was found that IF, regardless of diet, led to decreased weight gain and lower blood glucose levels [ 13 , 44 , 45 ]. These findings are supported by Bhoumik et al (2020), which used Wistar rats to evaluate the effects of a time-restricted feeding model of IF (18- hour fast, 6- hour fed) or alternate day fasting (24 hours fed, 24 hours fasted) compared to AL controls over a 4-week time period.…”