Structure elucidation of glycan of glycoconjugate LbGp3 isolated from the fruit of Lycium barbarum L

Effects of Lycium barbarum Polysaccharides on Immunity and Metabolic Syndrome Associated with the Modulation of Gut Microbiota: A Review

Lycium barbarum polysaccharides (LBPs) have attracted increasing attention due to their multiple pharmacological activities and physiological functions. Recently, both in vitro and in vivo studies have demonstrated that the biological effects of dietary LBPs are related to the regulation of gut microbiota. Supplementation with LBPs could modulate the composition of microbial communities, and simultaneously influence the levels of active metabolites, thus exerting their beneficial effects on host health. Interestingly, LBPs with diverse chemical structures may enrich or reduce certain specific intestinal microbes. The present review summarizes the extraction, purification, and structural types of LBPs and the regulation effects of LBPs on the gut microbiome and their derived metabolites. Furthermore, the health promoting effects of LBPs on host bidirectional immunity (e.g., immune enhancement and immune inflammation suppression) and metabolic syndrome (e.g., obesity, type 2 diabetes, and nonalcoholic fatty liver disease) by targeting gut microbiota are also discussed based on their structural types. The contents presented in this review might help to better understand the health benefits of LBPs targeting gut microbiota and provide a scientific basis to further clarify the structure–function relationship of LBPs.

Lycium Genus Polysaccharide: An Overview of its Extraction, Structures, Pharmacological Activities and Biological Applications

Polysaccharide is considered to be the main active ingredient of the genus Lycium L., which is taken from the dried fruit of the famous Chinese herbal medicine and precious tonic known as wolfberry. Traditional uses include nourishing the liver and kidney and improving eyesight, with widespread use in the clinical practice of traditional Chinese medicine. Many studies have focused on the isolation and identification of the genus Lycium L. polysaccharide and its biological activities. However, the variety of raw materials and the mechanisms of polysaccharides differ. After extraction, the structure and biological activity of the obtained polysaccharides also differ. To date, approximately 58 kinds of polysaccharides have been isolated and purified from the Lycium genus, including water-soluble polysaccharides; homogeneous polysaccharides; pectin polysaccharides; acidic heteropolysaccharides; and arabinogalactans, which are composed of arabinose, glucosamine, galactose, glucose, xylose, mannose, fructose, ribose, galacturonic acid, and glucuronic acid. Pharmacological studies have shown that LBPs exhibit a variety of important biological activities, such as protection of nerves; promotion of reproduction; and anti-inflammatory, hepatoprotective, hypoglycemic, and eyesight-improving activities. The aim this paper is to summarize previous and current references to the isolation process, structural characteristics, and biological activities of the genus Lycium L. polysaccharide. This review will provide a useful reference for further research and application of the genus Lycium L. polysaccharide in the field of functional food and medicine.

Lycium ruthenicum Murr polysaccharide protects cortical neurons against oxygen-glucose deprivation/reperfusion in neonatal hypoxic-ischemic encephalopathy

Neonatal hypoxic-ischemic encephalopathy (HIE) is a complex condition that remains the leading cause of mortality and morbidity among infants. Polysaccharide has been reported to possess diverse biological activities, however, the neuro-protective activity of polysaccharide isolated from Lycium ruthenicum remains unknown so far. However, the role of Lycium ruthenicum polysaccharide 3 (LRP3) in HIE has not been evaluated. Herein, we investigated the effect of LRP3 on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced primary cortical neurons. Our results demonstrated that LRP3 significantly improved the cell viability of OGD/R-induced cortical neurons. The OGD/R-caused increase in ROS production and decrease in the activities of anti-oxidative enzymes including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were mitigated by LRP3. Besides, the caspase-3 activity in OGD/R-induced cortical neurons was markedly decreased after LRP3 treatment. The increased bax expression and decreased bcl-2 expression caused by OGD/R stimulation were alleviated by pretreatment with LRP3. In addition, LRP3 significantly induced the expressions of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase-1 (HO-1) in OGD/R-induced cortical neurons. However, inhibition of Nrf2/HO-1 signaling pathway through transfection with siRNA targeting Nrf2 reversed the protective effects of LRP3. In conclusion, LRP3 exerts a neuroprotective effect against OGD/R-induced neuronal injury in rat primary cortical neurons.

Extraction, Structural Characterization, and Biological Functions of Lycium Barbarum Polysaccharides: A Review

Lycium barbarum polysaccharides (LBPs), as bioactive compounds extracted from L. barbarum L. fruit, have been widely explored for their potential health properties. The extraction and structural characterization methods of LBPs were reviewed to accurately understand the extraction method and structural and biological functions of LBPs. An overview of the biological functions of LBPs, such as antioxidant function, antitumor activity, neuroprotective effects, immune regulating function, and other functions, were summarized. This review provides an overview of LBPs and a theoretical basis for further studying and extending the applications of LBPs in the fields of medicine and food.

Lycium Barbarum Polysaccharides Improve Retinopathy in Diabetic Sprague-Dawley Rats

Diabetic retinopathy (DR) has become the most frequent cause of impaired visual acuity and blindness in working-age population in developed countries. Here we use diabetic rats to clarify the role of Lycium barbarum polysaccharides (LBP) on DR. We treated diabetic rats with LBP (400 mg/kg/d or 200 mg/kg/d) orally for 20 weeks. Electroretinogram (ERGs) and Laser Doppler blood flow were measured to assess the retinal function, routine histology and ultrastructural studies were performed to evaluate the morphological alterations, and immunohistochemistry, western blotting, and RT-PCR were conducted to detect the protein and mRNA levels of pro- and antiangiogenic factors. The results showed that diabetes suppressed the amplitudes of a-wave, b-wave, and oscillatory potential in ERG, reduced retinal blood flow, decreased the thickness of the retina, and increased the thickness of basement membrane of the retinal capillary. Furthermore, diabetes increased the mRNA and protein expressions of proangiogenic GFAP and VEGF and suppressed the levels of antiangiogenic PEDG. Treatment with LBP either completely or partially reversed the alterations caused by diabetes. It is concluded that the LBP protects retinal function and morphology in diabetic rats, probably through reinstallation of the balance between proangiogenic and antiangiogenic factors, which reduces neovascularization. LBP could be used as a therapeutic drug for DR.

Systematic Review of Chemical Constituents in the Genus Lycium (Solanaceae)

The Lycium genus is widely used as a traditional Chinese medicine and functional food. Many of the chemical constituents of the genus Lycium were reported previously. In this review, in addition to the polysaccharides, we have enumerated 355 chemical constituents and nutrients, including 22 glycerogalactolipids, 29 phenylpropanoids, 10 coumarins, 13 lignans, 32 flavonoids, 37 amides, 72 alkaloids, four anthraquinones, 32 organic acids, 39 terpenoids, 57 sterols, steroids, and their derivatives, five peptides and three other constituents. This comprehensive study could lay the foundation for further research on the Lycium genus.

Three New Dimers and Two Monomers of Phenolic Amides from the Fruits of Lycium barbarum and Their Antioxidant Activities

The aims of this study were to complement the current knowledge on the antioxidative composition of alcohol extracts from the fruits of Lycium barbarum and to evaluate their antioxidant activities. Three new dimers of phenolic amides, named lyciumamides A (3), B (4), and C (5), together with two monomers, N-E-coumaroyl tyramine (1) and N-E-feruloyl tyramine (2), were isolated from the fruits for the first time with the help of activity-guided chromatography. Compounds 1-5 were evaluated for their antioxidant activities in scavenging 2,2-diphenyl-1-picrylhydrazyl free radical and inhibiting lipid peroxidation in rat liver microsomes induced by ascorbate/Fe²⁺, cumine hydroperoxide, or CCl₄/reduced form of nicotinamide-adenine dinucleotide phosphate, and the results showed that all of them exhibited strong activities, whereas compounds 1 and 2 were more potent than the reference tert-butyl-4-hydroxyanisole.

An evidence-based update on the pharmacological activities and possible molecular targets of Lycium barbarum polysaccharides

Lycium barbarum berries, also named wolfberry, Fructus lycii, and Goji berries, have been used in the People’s Republic of China and other Asian countries for more than 2,000 years as a traditional medicinal herb and food supplement. L. barbarum polysaccharides (LBPs) are the primary active components of L. barbarum berries and have been reported to possess a wide array of pharmacological activities. Herein, we update our knowledge on the main pharmacological activities and possible molecular targets of LBPs. Several clinical studies in healthy subjects show that consumption of wolfberry juice improves general wellbeing and immune functions. LBPs are reported to have antioxidative and antiaging properties in different models. LBPs show antitumor activities against various types of cancer cells and inhibit tumor growth in nude mice through induction of apoptosis and cell cycle arrest. LBPs may potentiate the efficacy of lymphokine activated killer/interleukin-2 combination therapy in cancer patients. LBPs exhibit significant hypoglycemic effects and insulin-sensitizing activity by increasing glucose metabolism and insulin secretion and promoting pancreatic β-cell proliferation. They protect retinal ganglion cells in experimental models of glaucoma. LBPs protect the liver from injuries due to exposure to toxic chemicals or other insults. They also show potent immunoenhancing activities in vitro and in vivo. Furthermore, LBPs protect against neuronal injury and loss induced by β-amyloid peptide, glutamate excitotoxicity, ischemic/reperfusion, and other neurotoxic insults. LBPs ameliorate the symptoms of mice with Alzheimer’s disease and enhance neurogenesis in the hippocampus and subventricular zone, improving learning and memory abilities. They reduce irradiation- or chemotherapy-induced organ toxicities. LBPs are beneficial to male reproduction by increasing the quality, quantity, and motility of sperm, improving sexual performance, and protecting the testis against toxic insults. Moreover, LBPs exhibit hypolipidemic, cardioprotective, antiviral, and antiinflammatory activities. There is increasing evidence from preclinical and clinical studies supporting the therapeutic and health-promoting effects of LBPs, but further mechanistic and clinical studies are warranted to establish the dose–response relationships and safety profiles of LBPs.

An Evidence-Based Systematic Review of Goji (Lycium spp.) by the Natural Standard Research Collaboration

An evidence-based systematic review of goji (Lycium spp.) by the Natural Standard Research Collaboration consolidates the safety and efficacy data available in the scientific literature using a validated, reproducible grading rationale. This article includes written and statistical analysis of clinical trials, plus a compilation of expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.

Hot Water ExtractedLycium BarbarumandRehmannia GlutinosaInhibit Liver Inflammation and Fibrosis in Rats

Polysaccharide-rich Lycium barbarum and Rehmannia glutinosa have been considered to have immune-modulating activity. This study investigated the effects of water extracted Lycium barbarum and Rehmannia glutinosa (HE) on carbon tetrachloride ( CCl4)-induced liver injury in rats. Male Sprague-Dawley rats were randomly divided into: normal diet + peritoneal injection of olive oil (control), normal diet + CCl4injection ( CCl4), 1 × HE (0.05% HE for each) + CCl4(1 × HE), and 3 × HE (0.15% HE for each) + CCl4(3 × HE) groups. Rats were injected with 40% CCl4at a dose of 0.75 ml/kg body weight once a week for seven weeks, one week after herbal extract treatment. After eight week herbal extract treatment, pathohistological examination showed that both 1× and 3 × HE treatments diminished necrotic hepatocytes, chemoattraction of inflammatory cells, and liver fibrosis. Both 1× and 3 × HE treatments decreased plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, and reduced hepatic levels of pro-inflammatory cytokines — tumor necrosis factor-α and interleukin-1β — compared to CCl4treatment alone. The 1 × HE treatment increased hepatic anti-inflammatory cytokine IL-10 levels. Both the 1× and 3 × HE treatments suppressed liver fibrosis biomarkers — transforming growth factor-β1 and hydroxyproline. Therefore, treatment with water extracted Lycium barbarum and Rehmannia glutinosa (0.05% and 0.15% for each) for eight weeks protects against necrotic damage, indicated by decreases in plasma ALT and AST activities, and suppresses liver fibrosis by down-regulation of liver inflammation in rats with CCl4-induced liver injury.

Hot water-extracted Lycium barbarum and Rehmannia glutinosa inhibit proliferation and induce apoptosis of hepatocellular carcinoma cells

AIM: To investigate the effect of hot water-extracted Lycium barbarum (LBE) and Rehmannia glutinosa (RGE) on cell proliferation and apoptosis in rat and/or human hepatocellular carcinoma (HCC) cells.

METHODS: Rat (H-4-II-E) and human HCC (HA22T/VGH) cell lines were incubated with various concentrations (0-10 g/L) of hot water-extracted LBE and RGE. After 6-24 h incubation, cell proliferation (n = 6) was measured by a colorimetric method. The apoptotic cells (n = 6) were detected by flow cytometry. The expression of p53 protein (n = 3) was determined by SDS-PAGE and Western blotting.

RESULTS: Crude LBE (2-5 g/L) and RGE (2-10 g/L) dose-dependently inhibited proliferation of H-4-II-E cells by 11% (P < 0.05) to 85% (P < 0.01) after 6-24 h treatment. Crude LBE at a dose of 5 g/L suppressed cell proliferation of H-4-II-E cells more effectively than crude RGE after 6-24 h incubation (P < 0.01). Crude LBE (2-10 g/L) and RGE (2-5 g/L) also dose-dependently inhibited proliferation of HA22T/VGH cells by 14%-43% (P < 0.01) after 24 h. Crude LBE at a dose of 10 g/L inhibited the proliferation of HA22T/VGH cells more effectively than crude RGE (56.8% ± 1.6% vs 70.3% ± 3.1% of control, P = 0.0003 < 0.01). The apoptotic cells significantly increased in H-4-II-E cells after 24 h treatment with higher doses of crude LBE (2-5 g/L) and RGE (5-10 g/L) (P < 0.01). The expression of p53 protein in H-4-II-E cells was 119% and 143% of the control group compared with the LBE-treated (2, 5 g/L) groups, and 110% and 132% of the control group compared with the RGE -treated (5, 10 g/L) groups after 24 h.

CONCLUSION: Hot water-extracted crude LBE (2-5 g/L) and RGE (5-10 g/L) inhibit proliferation and stimulate p53-mediated apoptosis in HCC cells.

Increased IgA and IgG serum levels using a novel yam-boxthorn noodle in a BALB/c mouse model

To determine whether yam-boxthorn noodle, a newly developed functional noodle, has immunomodulatory effects in vivo, we measured the changes in visceral organ weight, immunoglobulin (Ig) A, IgE, IgG, IgM serum level and IgA level in the intestinal lavage fluid of female BALB/c mice after continuously consuming the test diet for 5 weeks. We found that body weights and absolute and relative organ weights (lung, heart, liver, spleen and kidney) in female BALB/c mice did not significantly change compared with those from the control group. The IgA and IgG serum levels in the experimental group significantly increased in a dose-dependent manner when the yam-boxthorn noodle concentration in the AIN 76 diet rose from 3% to 30%. However, the IgE and IgM level in the serum and the IgA level in the intestinal lavage fluid did not significantly change. These experiments demonstrate that the functional noodle, yam-boxthorn noodle, exhibits immunomodulatory effects in vivo with increasing serum antibody levels, especially in IgA and IgG. These results are valuable for future nutraceutical and immuno-pharmacological use.

Lycium barbarum glycoconjugates: effect on human skin and cultured dermal fibroblasts

Lycium barbarum L. (Solanaceae) glycoconjugates (LbGp) display an interesting array of anti-apoptotic and antioxidant properties, which may be beneficial for human skin. We therefore set out to determine the effects of LbGp in full-thickness human skin, and in dermal fibroblasts. It was found that LbGp decreased the level of MMP (matrix metalloproteinase)-1 significantly, but not that of MMP-3 or -13, in the whole human skin system, without compromising the viability of the skin. Consistently, LbGp inhibited skin expansion under mechanical stress, which in this model depends on the activity of MMP-1. We found that one of L. barbarum glycoconjugates, the LbGp5, promoted the survival of human fibroblasts cultured in suboptimal conditions. Furthermore, in the presence of LbGp5, these cultures also contained higher levels of the MMP-1 substrate--collagen type I. Together these results suggest that L. barbarum glycoconjugates in general, and LbGp5 in particular, may have important skin-protective properties.

Structural characterization of the glycan part of glycoconjugate LbGp2 from Lycium barbarum L

A glycoconjugate with pronounced immunoactivity, designated as LbGp2, was isolated from the fruit of Lycium barbarum L. and purified to homogeneity by gel-filtration. Its carbohydrate content is up to 90.71% composed of Ara, Gal and amino acids. The molecular weight is 68.2 kDa as determined by size exclusive chromatography (SEC). The complete structure of the repeat unit of the glycan of LbGp2 was elucidated based on glycosidic linkage analysis, total acid hydrolysis, partial acid hydrolysis, 1H and 13C NMR spectroscopy. According to the experiments, the glycan possesses a backbone consisting of (1-->6)-beta-galactosyl residues, about fifty percent of which are substituted at C-3 by galactosyl or arabinosyl groups and the major nonreducing end being made of Ara (1 -->.