Lycium barbarum glycopeptide(wolfberry extract)slows N-methyl-N-nitrosourea-induced degradation of photoreceptors

Photoreceptor cell degeneration leads to blindness, for which there is currently no effective treatment. Our previous studies have shown that Lycium barbarum(L. barbarum) polysaccharide(LBP) protects degenerated photoreceptors in rd1, a transgenic mouse model of retinitis pigmentosa. L. barbarum glycopeptide(Lb GP) is an immunoreactive glycoprotein extracted from LBP. In this study, we investigated the potential protective effect of Lb GP on a chemically induced photoreceptor-degenerative mouse model. Wild-type mice received the following: oral administration of Lb GP as a protective pre-treatment on days 1–7;intraperitoneal administration of 40 mg/kg N-methylN-nitrosourea to induce photoreceptor injury on day 7;and continuation of orally administered Lb GP on days 8–14. Treatment with Lb GP increased photoreceptor survival and improved the structure of photoreceptors, retinal photoresponse, and visual behaviors of mice with photoreceptor degeneration. Lb GP was also found to partially inhibit the activation of microglia in N-methyl-N-nitrosourea-injured retinas and significantly decreased the expression of two pro-inflammatory cytokines. In conclusion, Lb GP effectively slowed the rate of photoreceptor degeneration in N-methyl-N-nitrosourea-injured mice, possibly through an anti-inflammatory mechanism, and has potential as a candidate drug for the clinical treatment of photoreceptor degeneration.

Reversal of Apoptotic Resistance by Lycium barbarum Glycopeptide 3 in Aged T Cells

Objective To study whether Lycium barbarurn glycopeplide 3 （LBGP3） affects T cell apoptosis in aged mice. Methods LBGP3 was purified with DEAE cellulose and Sephadex columns. Apoptotic ＂sub-G1 peak＂ was detected by flow cytometry and DNA ladder was resolved by agarose gel electrophoresis. Levels of IFN-7 and IL-10 were measured with specific kits and mRNA expression was detected by RT-PCR. Apoptosis-related proteins of FLIP, FasL, and Bcl-2 were determined by Western blotting. Results LBGP3 was purified from Fructus Lycii water extracts and identified as a 41 kD glycopeptide. Treatment with 200 p.g/mL LBGP3 increased the apoptotic rate of T cells from aged mice and showed a similar DNA ladder pattern to that in young T cells. The reversal of apoptotic resistance was involved in down-regulating the expression of Bcl-2 and FLIP, and up-regulating the expression of FasL. Conclusion Lycium barbarum glycopeptide 3 reverses apoptotic resistance of aged T cells by modulating the expression of apoptosis-related molecules.

Experimental Study on the Enhancement of Murine Splenic Lymphocyte Proliferation by Lycium Barbarum Glycopeptide

In order to investigate the immunoactivity of Lycium Barbarum glycopeptide (LBG), the routinely prepared murine splenic lymphocyte suspension was separately added into the samples with different concentrations (500, 100, 10, 1 μg/ml) of LBG as LBG groups. Blank control group in the absence of Lycium Barbarum glycopeptide or ConA and positive control group in the presence of 0.5 ml ConA but in the absence of LBG were created. 0.5 ml LBG samples with different concentrations in combination with 0.5 ml ConA (10 μg/ml) into each well to observe the synergic effects of LBG and ConA as LBG+ConA groups. After incubation for 72 h at 37 ℃, the samples were analyzed by CFSE-labeled cells combined with flow cytometry, and MTT. Flow cytometry revealed that both LBG could enhance the murine splenic lymphocyte proliferative reaction. Combined use of LBG and ConA had synergic effects. MTT demonstrated that sample A could obviously promote the murine splenic lymphocyte proliferative reaction as compared with control group (P<0.01), while sample B could also enhance the lymphocyte proliferation at a high dose. In combination with ConA, sample A had synergic effects at high dose, while sample B showed obviously synergic effects (P<0.05). It was concluded that both samples (A and B) had strong immunocompetence.

Retinal ischemia-reperfusion injury and pretreatment with Lycium barbarum glycopeptide

AIM:To investigate the antioxidant protective effect of Lycium barbarum glycopeptide(LbGP)pretreatment on retinal ischemia-reperfusion(I/R)injury(RIRI)in rats.METHODS:RIRI was induced in Sprague Dawley rats through anterior chamber perfusion,and pretreatment involved administering LbGP via gavage for 7d.After 24h of reperfusion,serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),and creatinine(CREA)levels,retinal structure,expression of Caspase-3 and Caspase-8,superoxide dismutase(SOD)activity,and malondialdehyde(MDA)in the retina were measured.RESULTS:The pretreatment with LbGP effectively protected the retina and retinal tissue from edema and inflammation in the ganglion cell layer(GCL)and nerve fiber layer(NFL)of rats subjected to RIRI,as shown by light microscopy and optical coherence tomography(OCT).Serum AST was higher in the model group than in the blank group(P=0.042),but no difference was found in ALT,AST,and CREA across the LbGP groups and model group.Caspase-3 expression was higher in the model group than in the blank group(P=0.006),but no difference was found among LbGP groups and the model group.Caspase-8 expression was higher in the model group than in the blank group(P=0.000),and lower in the 400 mg/kg LbGP group than in the model group(P=0.016).SOD activity was lower in the model group than in the blank group(P=0.001),and the decrease was slower in the 400 mg/kg LbGP group than in the model group(P=0.003).MDA content was higher in the model group than in the blank group(P=0.001),and lower in the 400 mg/kg LbGP group than in the model group(P=0.016).The pretreatment with LbGP did not result in any observed liver or renal toxicity in the model.CONCLUSION:LbGP pretreatment exhibits dosedependent anti-inflammatory,and antioxidative effects by reducing Caspase-8 expression,preventing declines of SOD activity,and decreasing MDA content in the RIRI rat model.