Protective Effect of Chlorogenic Acid against Aβ-Induced Neurotoxicity

Abstract

Beta-amyloid (Aβ) is considered as one of the major causes of Alzheimer's disease. This study examined the neuroprotective effects of chlorogenic acid, a naturally occurring polyphenol which is distributed widely in plants, fruits and vegetables, against Aβ-induced toxicity. Aβ decreased signifi cantly the viability of PC12 cells. This was accompanied by an increase in the intracellular calcium levels and cleaved caspase-3. In addition, Aβ induced an increase in Bax, and a decrease in Bcl-2 compared to the controls. However, a pre-treatment with chlorogenic acid rescued the PC12 cells from Aβ by attenuating the elevated intracellular calcium levels and reducing the levels of the apoptosis related proteins, including caspase-3, Bcl-2 and Bax. These results suggest that the protective effects of chlorogenic acid are, at least in parts, by attenuating the intracellular calcium infl ux and reducing apoptosis induced by Aβ. Abstractthat is distributed widely in plants, fruits and vegetables, such as coffee beans, potatoes and apples (Clifford, 1999;Zang et al., 2003). It possesses a wide range of biological activities including anti-carcinogenic, anti-bacterial, anti-infl ammatory and antioxidant activities in vitro (Huang et al., 1988;Almeida et al., 2006;dos Santos et al., 2006). However, the possible benefi cial effects of chlorogenic acid against Aβ have not been elucidated. Therefore, this study evaluated the neuroprotective effects of chlorogenic acid against Aβ-induced toxicity in PC12 cells (rat pheochromocytoma). To accomplish this, an MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay was carried out to determine if chlorogenic acid protected the PC12 cells against Aβ. To examine their underlying mechanisms, the effects of chlorogenic acid on the intracellular calcium level and apoptosis related proteins including Bcl-2, Bax and caspase-3 were evaluated as possible neuroprotective mechanisms against Aβ.

Chlorogenic Acid Potentiates the Anti-Inflammatory Activity of Curcumin in LPS-Stimulated THP-1 Cells

“…Similar protective effects of CGA on cell viability have been reported previously [37][38][39][40]. It is possible that CGA can modulate apoptotic genes in LPS stimulated THP-1 macrophages as CGA has been shown to increase the production of B-cell lymphoma-2 (Bcl-2) and decrease the production of Bax, anti-apoptotic and pro-apoptotic proteins, respectively, and decrease caspase-3 in β-amyloid stimulated PC12 cells within 1 h of treatment [41]. To the best of our knowledge, our study is the first to demonstrate the protective effect of CGA in human immune cells.…”

Effect of Thermal Processing and Maceration on the Antioxidant Activity of White Beans

“…This phenolic compound can be easily oxidised by polyphenol oxidases, leading to interactions with the NH 2 groups of amino acids and resulting in a reduction of the nutritional value of foods. Chlorogenic acid reduced with the cooking process ( Figure 3 and Table 1 ) [30] , [35] .…”

Protective Effects of Fucoidan on Aβ25–35 and d-Gal-Induced Neurotoxicity in PC12 Cells and d-Gal-Induced Cognitive Dysfunction in Mice

“…In this paper, the regulation of the caspase-dependent apoptotic pathway by fucoidan was investigated. We found fucoidan could upregulate the expressions of two apoptosis inhibitor proteins, XIAP and livin, which could mediate the activation of apoptosis pathways, both intrinsic and extrinsic [21]. It is well known that caspase-3 has proved to play an important role in the process of aging induced by Aβ.…”