Caloric restriction: A potential approach for mitigating neuronal damage: Lesson from cellular model of Alzheimer Disease

Alzheimers disease is a neurodegenerative disorder and characterized by amyloid beta accumulation, synaptic dysfunction, and oxidative stress, lacks effective therapies. Caloric restriction mimetics such as fisetin and chlorogenic acid, natural polyphenols with antioxidant and autophagy-inducing properties, show promise in mitigating age-related diseases. This study investigates their neuroprotective effects against amyloid beta induced toxicity in differentiated human neuroblastoma SHSY5Y cells. Amyloid beta exposure disrupted redox homeostasis, impaired autophagy, induced mitochondrial dysfunction, and exacerbating neuronal degeneration. Fisetin and chlorogenic acid treatments reversed these deleterious effects by restoring redox balance, suppressing reactive oxygen species and upregulating critical antioxidant enzymes like SOD1, GSR, and catalase. These compounds also attenuated amyloid beta induced mitophagy via reduced PINK1 expression and restored mitochondrial fusion by upregulating Mfn2. Autophagy-related pathways were significantly modulated, evidenced by increased AMPK and decreased mTOR mRNA levels, alongside elevated expression of ATG101, ATG13, ULK1, P62 and reduced ATG5 levels. Docking studies also revealed binding of fisetin and CGA within the binding pockets of AMPK and FKBP12 supporting their interaction. Furthermore, fisetin and CGA improved synaptic integrity by upregulating PSD95 and synaptophysin and reducing acetylcholinesterase expression. These findings highlight their potential in ameliorating amyloid beta induced neuronal toxicity through autophagy activation, synaptic preservation, and mitochondrial function enhancement. While this study demonstrates the transcriptional impact and binding affinities of these caloric restriction mimetics further translational and biophysical analyses are required to elucidate their mechanisms and confirm their therapeutic viability. This research underscores the potential of fisetin and CGA as neuroprotective agents, offering promising therapeutic avenues for combating related Alzheimers disease neuropathies. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=128 SRC="FIGDIR/small/628076v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@1253dd0org.highwire.dtl.DTLVardef@1fd3ffforg.highwire.dtl.DTLVardef@1749d1dorg.highwire.dtl.DTLVardef@f71415_HPS_FORMAT_FIGEXP M_FIG C_FIG