Quelques études scientifiques sur le GOJI

(Malheureusement, aucune traduction n'est disponible en français.

Vous pouvez CLIQUER ICI pour avoir une traduction automatique de cette page

Wushu Department, Guangzhou sport university, Guangzhou 510500, China.

The aim of this study was to determine the modulatory effect of Lycium barbarum polysaccharides (LBP) on the oxidative stress induced by an exhaustive exercise. 32 male Wistar rats were taken in the study. The experiment was a 30-day exhaustive exercise program. We determined the lipid peroxidation, glycogen levels, and anti-oxidant enzyme activities in skeletal muscle. The results demonstrated that L. barbarum polysaccharides administration significantly increases glycogen level and anti-oxidant enzyme activities, and decreased malondialdehyde (MDA) level and creatine kinase activities. In conclusion, L. barbarum polysaccharides administration can significantly decrease the oxidative stress induced by the exhaustive exercise.

PMID: 18405964

Center for Human Nutrition, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA.

An overwhelming body of research has now firmly established that the dietary intake of berry fruits has a positive and profound impact on human health, performance, and disease. Berry fruits, which are commercially cultivated and commonly consumed in fresh and processed forms in North America, include blackberry ( Rubus spp.), black raspberry ( Rubus occidentalis), blueberry ( Vaccinium corymbosum), cranberry (i.e., the American cranberry, Vaccinium macrocarpon, distinct from the European cranberry, V. oxycoccus), red raspberry ( Rubus idaeus) and strawberry ( Fragaria x ananassa). Other berry fruits, which are lesser known but consumed in the traditional diets of North American tribal communities, include chokecherry ( Prunus virginiana), highbush cranberry ( Viburnum trilobum), serviceberry ( Amelanchier alnifolia), and silver buffaloberry ( Shepherdia argentea). In addition, berry fruits such as arctic bramble ( Rubus articus), bilberries ( Vaccinuim myrtillus; also known as bog whortleberries), black currant ( Ribes nigrum), boysenberries ( Rubus spp.), cloudberries ( Rubus chamaemorus), crowberries ( Empetrum nigrum, E. hermaphroditum), elderberries ( Sambucus spp.), gooseberry ( Ribes uva-crispa), lingonberries ( Vaccinium vitis-idaea), loganberry ( Rubus loganobaccus), marionberries ( Rubus spp.), Rowan berries ( Sorbus spp.), and sea buckthorn ( Hippophae rhamnoides), are also popularly consumed in other parts of the world. Recently, there has also been a surge in the consumption of exotic "berry-type" fruits such as the pomegranate ( Punica granatum), goji berries ( Lycium barbarum; also known as wolfberry), mangosteen ( Garcinia mangostana), the Brazilian açaí berry ( Euterpe oleraceae), and the Chilean maqui berry ( Aristotelia chilensis). Given the wide consumption of berry fruits and their potential impact on human health and disease, conferences and symposia that target the latest scientific research (and, of equal importance, the dissemination of this information to the general public), on the chemistry and biological and physiological functions of these "superfoods" are necessary.

PMID: 18211023

 Department of Environmental Health, Ningxia Medical College, Yinchuan 750004, China.

Étude intéressante sur des rats

OBJECTIVE: To explore the effects of Lycium barbarum (L) on the behavior and body weight and TNF-alpha level of rat treated with binding. METHODS: Rats were randomly divided into 6 groups: control group,binding group, 2.5% L group, 5.0% L group, 2.5% L plus binding group, 5.0% L plus binding group. Lycium barbarums were pressed into juice, then rats were fed with the dranking water contening juice. Rats were bound to restrict for 21 days. RESULTS: (1) The increases of serum-cortisol level and the decreases of body weight and the increases of TNF-alpha level of rats of binding group in comparision with control groups (P < 0.05) (2) Rats body weight gain, movement and TNF-alpha level in both of 2.5% L plus binding group and 5.0% L plus binding group were more higher than those in binding group (P < 0.05). Serum-cortisol level of these two groups were more lower and had statistical significance in comparison with those of binding groups (P < 0.05). CONCLUSION: Binding could suppress body weight gain and markedly reduce the activity and TNF-alpha level of rat. Lycium barbarum could be a good adjustment on the behavior, body weight and TNF-alpha.

PMID: 18303642

Department of Sanitary Technology, West China School of Public Health, Sichuan University, Chengdu, China.

OBJECTIVE: To develop a rapid approach of refractive index detection with high performance liquid chromatography (HPLC) for the determination of rhamnose, fructose, glucose, surose and maltose in Lycium barbarum L. METHODS: The sample was extracted with water and the analyte was separated by Zorbax Carbohydrate column with acetonitrile-water as mobile phase. RESULTS: Good linear correlations between the concentrations and the peak areas of the analyte were found, with the correlation coefficients ranging from 0.9976 to 0.9998. The spiked recovery rates ranged from 92.27% to 101.93%, with 1.85%-3.27% of relative standard deviations (n=5). The limits of detection (S/N =3) were 4-6 mg/kg. CONCLUSION: The proposed method is suitable for the determination of monosaccharide and oligosaccharide in Lycium barbarum L.

PMID: 18095617  

Recherche sur les différentes variétés de Lycium

Fructus Lycii (Gouqizi) is well-known in Chinese herbal medicine for its restorative function of benefiting the liver and the kidney, replenishing vital essence and improving eyesight. However, ten species and varieties of Lycium are found to be substitutes or adulterants of L. barbarum in the commercial market in Hong Kong and China. L. barbarum cv. 'Tianjinense' and L. chinense var. potaninii are the most common examples. It is difficult to differentiate among the Lycium species by traditional morphological and histological analysis. An easy and reliable approach based on SCAR (Sequence Characterized Amplified Region) analysis was developed in this study to differentiate L. barbarum from other Lycium species. Two characteristic bands of about 700 and 650 bp were detected on the RAPD (Random Amplified Polymorphic DNA) profiles generated from samples of L. barbarum and L. chinense var. potaninii using primer OPC-7. They were isolated and sequenced. Two primer sets, based on the sequences, could amplify a single specific band in samples of L. barbarum respectively while no bands were detected in samples of L. chinense var. potaninii. The results confirmed that the SCAR technique can be employed for authenticating L. barbarum and its adulterants.

PMID: 18052933 

Laboratory of Neurodegenerative Diseases, Department of Anatomy, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.

Lycium barbarum (Gouqizi, Fructus Lycii, Wolfberry) is well known for nourishing the liver, and in turn, improving the eyesight. However, many people have forgotten its anti-aging properties. Valuable components of L. barbarum are not limited to its colored components containing zeaxanthin and carotene, but include the polysaccharides and small molecules such as betaine, cerebroside, beta-sitosterol, p-coumaric, and various vitamins. Despite the fact that L. barbarum has been used for centuries, its beneficial effects to our bodies have not been comprehensively studied with modern technology to unravel its therapeutic effects at the biochemical level. Recently, our laboratory has demonstrated its neuroprotective effects to counter neuronal loss in neurodegenerative diseases. Polysaccharides extracted from L. barbarum can protect neurons against beta-amyloid peptide toxicity in neuronal cell cultures, and retinal ganglion cells in an experimental model of glaucoma. We have even isolated the active component of polysaccharide which can attenuate stress kinases and pro-apoptotic signaling pathways. We have accumulated scientific evidence for its anti-aging effects that should be highlighted for modern preventive medicine. This review is to provide background information and a new direction of study for the anti-aging properties of L. barbarum. We hope that new findings for L. barbarum will pave a new avenue for the use of Chinese medicine in modern evidence-based medicine.

PMID: 17710531

Laboratory of Neurodegenerative Diseases, Department of Anatomy, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.

Étude prouvant que les Polysaccharides du Lycium Barbarum retardent le vieillissement des cellules

Lycium barbarum (Gouqizi, Fructus Lycii, Wolfberry) is well known for nourishing the liver, and in turn, improving the eyesight. However, many people have forgotten its anti-aging properties. Valuable components of L. barbarum are not limited to its colored components containing zeaxanthin and carotene, but include the polysaccharides and small molecules such as betaine, cerebroside, beta-sitosterol, p-coumaric, and various vitamins. Despite the fact that L. barbarum has been used for centuries, its beneficial effects to our bodies have not been comprehensively studied with modern technology to unravel its therapeutic effects at the biochemical level. Recently, our laboratory has demonstrated its neuroprotective effects to counter neuronal loss in neurodegenerative diseases. Polysaccharides extracted from L. barbarum can protect neurons against beta-amyloid peptide toxicity in neuronal cell cultures, and retinal ganglion cells in an experimental model of glaucoma. We have even isolated the active component of polysaccharide which can attenuate stress kinases and pro-apoptotic signaling pathways. We have accumulated scientific evidence for its anti-aging effects that should be highlighted for modern preventive medicine. This review is to provide background information and a new direction of study for the anti-aging properties of L. barbarum. We hope that new findings for L. barbarum will pave a new avenue for the use of Chinese medicine in modern evidence-based medicine.

PMID: 17710531

State Key Laboratory of Safety Evaluation for New Drug, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, China.

Étude prouvant l'effet antioxydant du Lycium Barbarum, diminution de 13% du taux de mortalité chez des rats

The objective of this work was to explore the hypothesis that Lycium barbarum (LB) may be protective against doxorubicin (DOX)-induced cardiotoxicity through antioxidant-mediated mechanisms. Male SD rats were treated with distilled water or a water extract of LB (25 mg/kg, p.o.) daily and saline or DOX (5 mg/kg, i.v.) weekly for 3 weeks. Mortality, general condition and body weight were observed during the experiment. DOX-induced cardiotoxicity was assessed by electrocardiograph, heart antioxidant activity, serum levels of creatine kinase (CK) and aspartate aminotransferase (AST) and histopathological change. The DOX group showed higher mortality (38%) and worse physical characterization. Moreover, DOX caused myocardial injury manifested by arrhythmias and conduction abnormalities in ECG (increased QT and ST intervals and ST elevation), a decrease of heart antioxidant activity, an increase of serum CK and AST, as well as myocardial lesions. Pretreatment with LB significantly prevented the loss of myofibrils and improved the heart function of the DOX-treated rats as evidenced from lower mortality (13%), normalization of antioxidative activity and serum AST and CK, as well as improving arrhythmias and conduction abnormalities. These results suggested that LB elicited a typical cardioprotective effect on DOX-related oxidative stress. Furthermore, in vitro cytotoxic study showed the antitumor activity of DOX was not compromised by LB. It is possible that LB could be used as a useful adjunct in combination with DOX chemotherapy. Copyright (c) 2007 John Wiley & Sons, Ltd.

PMID: 17622973

Laboratory of Neurodegenerative Diseases, Department of Anatomy, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, P.R. China.

Étude sur l'Alzheimer

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 beta-amyloid (A beta) 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 A beta and dithiothreitol. We also showed that the polysaccharide-containing 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 A beta 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 A beta-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 A beta peptide-activated caspase-3-like activity. LBP-III markedly reduced the phosphorylation of PKR triggered by A beta peptide. Since the phosphorylation state of PKR increased with age, reduction of its phosphorylation triggered by A beta 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.

PMID: 17611646

Department of Biochemistry and Molecular Biology, College of Medicine, Zhejiang University, Hangzhou 310006, Republic of China.

Le Lycium Barbarum et les Polysaccharides

Lycium barbarum polysaccharides (LBPs) have been known to have a variety of immunomodulatory functions including activation of T cells, B cells and NK cells. Dendritic cells (DC) are potent antigen-presenting cells that play pivotal roles in the initiation of the primary immune response. However, little is known about the immunomodulatory effects of LBPs on murine bone marrow derived dendritic cells (BMDC). In the present study, the effects of LBPs on the phenotypic and functional maturation of murine BMDC were investigated in vitro. Compared to the BMDC that were only subjected to treatment with RPMI1640, the co-expression of I-A/I-E, CD11c and secretion of IL-12 p40 by BMDC stimulated with LBPs (100 microg/ml) were increased. In addition, the endocytosis of FITC-dextran by LBPs-treated BMDC (100 microg/ml) was impaired, whereas the activation of proliferation of allogenic lymphocytes by BMDC was enhanced. Our results strongly suggest that LBPs are capable of promoting both the phenotypic and functional maturation of murine BMDC in vitro.

PMID: 17289406