The anti-apoptotic, antioxidant and anti-inflammatory effects of curcumin on acrylamide-induced neurotoxicity in rats

Abstract

Background: Acrylamide (ACR) formed during heating of tobacco and carbohydrate-rich food as well as widely applied in industries has been known as a well-established neurotoxic pollutant. Although the precise mechanism is unclear, enhanced apoptosis, oxidative stress and inflammation have been demonstrated to contribute to the ACRinduced neurotoxicity. In this study, we assessed the possible anti-apoptotic, antioxidant and anti-inflammatory effects of curcumin, the most active component in a popular spice known as turmeric, on the neurotoxicity caused by ACR in rats. Methods: Curcumin at the dose of 50 and 100 mg/kg was orally given to ACR-intoxicated Sprague-Dawley rats exposed by ACR at 40 mg/kg for 4 weeks. All rats were subjected to behavioral analysis. The HE staining and terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (TUNEL) staining were used to detect histopathological changes and apoptotic cells, respectively. The mRNA and protein expressions of apoptosis-related molecule telomerase reverse transcriptase (TERT) were detected using real-time PCR and immunohistochemistry, respectively. The contents of malondialdehyde (MDA) and glutathione (GSH) as well as the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured as the indicators for evaluating the level of oxidative stress in brain. The levels of pro-inflammatory cytokinestumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the cerebral homogenates were detected using ELISA assay. Results: ACR-induced weigh loss, deficits in motor function as well as pathological alterations in brains were significantly improved in rats administrated with 50 and 100 mg/kg curcumin. TUNEL-positive apoptotic cells in curcumin-treated ACR intoxicated brains were less than those in the ACR model group. Curcumin administration especially at the dose of 100 mg/kg upregulated the TERT mRNA expression and enhanced the number of TERTpositive cells in ACR-intoxicated cortex tissues. Moreover, curcumin treatment reduced the concentrations of TNF-α, IL-1β and MDA, while increased the GSH contents as well as the SOD and GSH-Px activities in the cerebral homogenates, in comparison to ACR control group.

Curcumin and Nano-Curcumin Mitigate Copper Neurotoxicity by Modulating Oxidative Stress, Inflammation, and Akt/GSK-3β Signaling

“…The ability of CUR to suppress inflammation has been reported in several studies. In a rat model of acrylamide neurotoxicity, Guo et al [49] showed that CUR attenuated neuroinflammation by decreasing TNF-α and IL-1β levels. In addition, CUR decreased circulating TNF-α in an animal model of lead neurotoxicity [50].…”

Effect of Acrylamide Supplementation on the Population of Vasoactive Intestinal Peptide (VIP)-Like Immunoreactive Neurons in the Porcine Small Intestine

“…Furthermore, numerous studies indicate that ACM, by the accumulation of excessive reactive oxygen species (ROS), causes oxidative stress and leads to damage in different organs of the body, including the brain, liver, and kidneys [ 43 ]. Notably, oxidative stress and enhanced lipid peroxidation are one of the main mechanisms of ACR-induced neurotoxicity [ 44 ]. The results obtained in the present study may be a response of ENS neurons to oxidative stress.…”

Potential Health Benefits of Curcumin on Female Reproductive Disorders: A Review

“…Curcumin has been shown to inhibit apoptosis in some diseases while promoting it in others [ 62 , 63 , 64 ]. Nanoparticle curcumin treatment reportedly decreased Bcl-2-associated X protein (BAX) and caspase3 (CASP3) protein expression and increased the levels of B-cell lymphoma 2 (Bcl2) expression.…”