Characterization of the effects of anti-aging medicine Fructus lycii on β-amyloid peptide neurotoxicity

Abstract

Abstract. Alzheimer's disease (AD) is an age-related neurodegenerative disease. There are increasing lines of evidence showing that the molecular signaling pathways in aged cells are altered so that cells are susceptible to injury. We and other laboratories have demonstrated the significant involvement of double-stranded RNA-dependent protein kinase (PKR) in ß-amyloid (Aß) peptide neurotoxicity and in AD. Fructus lycii (the fruit of Lycium barbarum) has long been used in oriental medicine as an anti-aging agent. Our previous studies demonstrated that the aqueous extract isolated from L. barbarum exhibited significant protection on cultured neurons against harmful chemical toxins such as Aß and dithiothreitol. We also showed that the polysaccharidecontaining extract (LBP) from L. barbarum exhibited neuroprotective effects in the retina against ocular hypertension in a laser-induced glaucoma animal model. In this study, we aimed to investigate whether LBP can elicit neuroprotection to neurons stressed by Aß peptides. Furthermore, we planned to isolate and identify the neuroprotective agent from LBP using chromatographic methods. Our results showed that pretreatment of LBP effectively protected neurons against Aß-induced apoptosis by reducing the activity of both caspase-3 and -2, but not caspase-8 and -9. A new arabinogalactan-protein (LBP-III) was isolated from LBP and attenuated Aß peptide-activated caspase-3-like activity.LBP-III markedly reduced the phosphorylation of PKR triggered by Aß peptide. Since the phosphorylation state of PKR increased with age, reduction of its phosphorylation triggered by Aß peptide may implicate that LBP-III from Fructus lycii is a potential neuroprotective agent in AD. As herbal medicine has received increasing attention for the treatment of AD, our study will open a window for the development of a neuroprotective agent for anti-aging from Chinese medicine.

Animal Models of Retinal Ischemia

“…The extracts from wolfberries (Lycium barbarum, Gougizi) mostly consist of polysaccharides and are believed to be good for the eye. It has also been shown previously in many studies that these extracts have protective effect against liver damage, ageing and oxidation (Ha, et al, 2005, Li, et al, 2007, Yu, et al, 2007.The group created a model by occluding the internal carotid artery in rats. The extracts were given orally for 1 week before the occlusion.…”

Lycium barbarum Fruit (Goji) Attenuates the Adrenal Steroid Response to an Exercise Challenge and the Feeling of Tiredness: A Randomized, Double-blind, Placebo-controlled Human Clinical Study

“…The juice was processed in an aseptic manner and kept refrigerated before use at 2 to 8 ºC. GoChi is standardized to contain a content of LBP equivalent to that found in at least 150 g of fresh fruit in 120 ml, the amount customarily consumed in traditional Chinese medicine (Yu et al, 2007;Amagase et al, 2011a). Based on our previous dose-seeking study on energy expenditure (Amagase et al, 2011b) and other various studies (Amagase et al, 2008(Amagase et al, , 2009a(Amagase et al, , 2009b, we used 120 ml of GoChi in the present studies as an established dose.…”

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“…Through these constituents, Lycium barbarum exhibits a powerful antioxidant and cytoprotective effect: hypoglycemic (Shaban et al, 1990;Wu et al, 2006), hypolipemic (Zhao et al, 2005;Luo et al, 2004), cardio- (Xu et al, 2005), neuro- (Lin et al, 2003;Yu et al, 2006;Yu et al, 2007), pancreatoand hepatoprotective (Kim et al, 1997;Chin et al, 2003;Slemmer et al, 2008), anti-aging (Zhao et al, 2005;Li et al, 2007b), anti-arterial hypertension (Jia et al, 1998;Chan et al, 2007); it contributes to increasing the body's resistance to physical exercise, etc.…”