chrysin and Cognitive-Dysfunction

Traumatic brain injury (TBI) is recognized as an important risk factor for cognitive deficits. The present study was designed to determine the potential neuroprotective effects of chrysin, a natural flavonoid compound, against TBI-induced spatial cognitive decline and the possible mechanisms involved. Oral administration of chrysin (25, 50, or 100 mg/kg/day) was initiated in rats immediately following the induction of the diffuse TBI model using the weight-dropping Marmarou model. Spatial cognitive ability, hippocampal synaptic plasticity, blood-brain barrier (BBB) permeability, brain water content, and histological changes were assessed at scheduled time points. The animals subjected to TBI exhibited spatial cognitive decline in the Morris water maze (MWM) test, which was accompanied by inhibition of hippocampal long-term potentiation (LTP) induction at the perforant path-dentate gyrus (PP-DG) synapses. Additionally, TBI caused BBB disruption, brain edema, and neuronal loss. Interestingly, treatment with chrysin (especially in the dose of 100 mg/kg) alleviated all the above-mentioned neuropathological changes related to TBI. The results provide evidence that chrysin improves TBI-induced spatial cognitive decline, which may be partly related to the amelioration of hippocampal synaptic dysfunction, alleviation of BBB disruption, reduction of brain edema, and prevention of neuronal loss.

Topics: Animals; Brain Concussion; Brain Edema; Brain Injuries, Traumatic; Cognitive Dysfunction; Flavonoids; Hippocampus; Maze Learning; Neuroprotective Agents; Rats

Many cancer survivors suffer from chemotherapy-induced cognitive impairment known as 'Chemobrain'. Doxorubicin -topoisomerase II inhibitor- is widely used in breast cancer, hematological cancers and other neoplasms. However, it is reported to precipitate cognitive impairment in cancer patients via inducing oxidative stress and inflammatory response. Chrysin -5,7 dihydroxyflavone- has promising antioxidant, anti-inflammatory and anticancer properties, but suffers low bioavailability owing to its poor solubility and extensive metabolism. In the present study, chrysin was successfully formulated as transfersomal lipid vesicles and chitosan composite vesicles (CCV) exhibiting a nanometric size range, high drug entrapment efficiency, and controlled release over a 72h period. Intranasal administration of optimized chrysin formulations at a reduced dose of 0.5 mg/kg improved doxorubicin-induced memory impairment in rats evidenced by behavioral testing, inhibition of acetylcholinesterase activity and oxidative stress markers; catalase, reduced glutathione, lipid peroxidation and hydrogen peroxide. This could reduce caspase-3 expression inhibiting apoptosis. Moreover, chrysin formulations were able to inhibit doxorubicin-induced Tol-like receptor 4 (TLR4) and p65 subunit of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) protein expression which in turn, reduced procaspase-1, Cysteinyl Aspartate Protease-1 (caspase-1) and Interleukin-1β (IL-1β) protein expression via inhibiting Nod-like receptor pyrin containing 3 (NLRP3) inflammasome. Collectively, our findings suggest the enhanced therapeutic potential of chrysin when formulated as transfersomes and CCV against chemotherapy-induced chemobrain via hindering acetylcholinesterase, oxidative stress and TLR4-NF-kB(p65)-NLRP3 pathways.

Topics: Administration, Intranasal; Animals; Antibiotics, Antineoplastic; Antioxidants; Brain; Chitosan; Cognitive Dysfunction; Doxorubicin; Drug Carriers; Drug Compounding; Drug Delivery Systems; Flavonoids; Male; NF-kappa B; NLR Family, Pyrin Domain-Containing 3 Protein; Oxidative Stress; Rats; Rats, Sprague-Dawley; Signal Transduction; Toll-Like Receptor 4

Ischemic stroke is one of the leading causes of death worldwide, and extensive efforts have focused on the neuroprotective strategies to minimize complications due to ischemia. This study aimed to examine neuroprotective potential of chrysin, as a natural potent antioxidative and anti-inflammatory agent in an animal model of bilateral common carotid artery occlusion and reperfusion (BCCAO/R).. Adult male Wistar rats (250-300 g) were randomly divided into 6 groups and submitted to either sham surgery or BCCAO/R after pretreatment with chrysin (10, 30 and 100 mg/kg, once daily, for 21 consecutive days) or saline containing %5 DMSO. To make the animal model of BCCAO/R, bilateral common carotid arteries were occluded for 20 min, followed by reperfusion. Subsequently, spatial cognitive performance was evaluated in a Morris water maze (MWM), hippocampal long-term potentiation (LTP) was recorded from hippocampal dentate gyrus region, after then the hippocampal tissue content of IL-1β and TNF-α were assayed using ELISA kits.. The results showed that pretreatment with chrysin significantly prevented BCCAO/R-induced cognitive and hippocampal LTP impairments (p < 0.001). Additionally, BCCAO/R- induced elevation in hippocampal content of IL-1β and TNF-α significantly (p < 0.01, p < 0.01 respectively) while pre-treatment with chrysin restored them (p < 0.01).. Our data confirm that chrysin could prevent brain inflammation and thereby prevents cognitive and LTP impairments due to cerebral ischemia. So it could be a promising neuroprotective agent against cerebrovascular insufficiency states.

Topics: Animals; Antioxidants; Brain Ischemia; Carotid Arteries; Carotid Artery, Common; Cognition; Cognitive Dysfunction; Disease Models, Animal; Encephalitis; Flavonoids; Hippocampus; Inflammation; Long-Term Potentiation; Male; Neuroprotective Agents; Oxidative Stress; Rats; Rats, Wistar; Reperfusion Injury