Juniperus pingii var. wilsonii acidic polysaccharide: Extraction, characterization and anticomplement activity

Functional properties, structural characteristics, and anti-complementary activities of two degraded polysaccharides from strawberry fruits

Two low-molecular-weight polysaccharides (DPSP50 and DPSP70) were obtained using hydrogen peroxide-vitamin C (H2O2-Vc) treatment at 50 °C and 70 °C, respectively. Both DPSP50 and DPSP70 comprised the same six monosaccharides in different ratios, and their molecular weights (Mws) were 640 kDa and 346 kDa, respectively. Functional properties analyses demonstrated that DPSP50 and DPSP70 each had an excellent water holding capacity, oil absorption capacity, and emulsion properties, as well as shear-thinning characteristics and viscoelastic properties. Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopic assays confirmed the existence of α-, β-pyranose rings and the same six sugar residues in DPSP50 and DPSP70. The results of Congo red test, scanning electron microscopy (SEM), and X-ray diffraction (XRD) demonstrated that DPSP50 and DPSP70 did not contain triple-helix conformations, but were amorphous aggregates with flake-like shape and rough surface. Additionally, both DPSP50 and DPSP70 showed strong anti-complementary activities through the classical pathway and the alternative pathway. The results support the potential utility of these degraded polysaccharides from strawberry fruits in functional foods and medicines.

Anticancer and anti-angiogenic activities of mannooligosaccharides extracted from coconut meal on colorectal carcinoma cells in vitro

Colorectal carcinoma (CRC) is one of the most common malignancies, though there are no effective therapeutic regimens at present. This study aimed to investigate the inhibitory effects of mannooligosaccharides extracted from coconut meal (CMOSs) on the proliferation and migration of human colorectal cancer HCT116 cells in vitro. The results showed that CMOSs exhibited significant inhibitory activity against HCT116 cell proliferation in a concentration-dependent manner with less cytotoxic effects on the Vero normal cells. CMOSs displayed the ability to increase the activation of caspase-8, -9, and -3/7, as well as the generation of reactive oxygen species (ROS). Moreover, CMOSs suppressed HCT116 cell migration in vitro. Interestingly, treatment of human microvascular endothelial cells (HMVECs) with CMOSs resulted in the inhibition of cell proliferation, cell migration, and capillary-like tube formation, suggesting its anti-vascular angiogenesis. In summary, the results of this study indicate that CMOSs could be a valuable therapeutic candidate for CRC treatment.

Structural Characterization and Anticomplement Activity of an Acidic Heteropolysaccharide from Lysimachia christinae Hance

A novel acidic heteropolysaccharide (LCP-90-1) was isolated and purified from a traditional "heat-clearing" Chinese medicine, Lysimachia christinae Hance. LCP-90-1 (Mw, 20.65 kDa) was composed of Man, Rha, GlcA, Glc, Gal, and Ara, with relative molar ratios of 1.00: 3.00: 11.62: 1.31: 1.64: 5.24. The backbone consisted of 1,4-α-D-GlcpA, 1,4-α-D-Glcp, 1,4-β-L-Rhap, and 1,3,5-α-L-Araf, with three branches of β-D-Galp-(1 → 4)-β-L-Rhap-(1→, α-L-Araf-(1→ and α-D-Manp-(1→ attached to the C-5 position of 1,3,5-α-L-Araf. LCP-90-1 exhibited potent anticomplement activity (CH50: 135.01 ± 0.68 µg/mL) in vitro, which was significantly enhanced with increased glucuronic acid (GlcA) content in its degradation production (LCP-90-1-A, CH50: 28.26 ± 0.39 µg/mL). However, both LCP-90-1 and LCP90-1-A were inactivated after reduction or complete acid hydrolysis. These observations indicated the important role of GlcA in LCP-90-1 and associated derivatives with respect to anticomplement activity. Similarly, compared with LCP-90-1, the antioxidant activity of LCP-90-1-A was also enhanced. Thus, polysaccharides with a high content of GlcA might be important and effective substances of L. christinae.

Exploring the partial degradation of polysaccharides: Structure, mechanism, bioactivities, and perspectives

Polysaccharides are promising biomolecules with lowtoxicity and diverse bioactivities in food processing and clinical drug development. However, an essential prerequisite for their applications is the fine structure characterization. Due to the complexity of polysaccharide structure, partial degradation is a powerful tool for fine structure analysis, which can effectively provide valid information on the structure of backbone and branching glycosidic fragments of complex polysaccharides. This review aims to conclude current methods of partial degradation employed for polysaccharide structural characterization, discuss the molecular mechanisms, and describe the molecular structure and solution properties of degraded polysaccharides. In addition, the effects of polysaccharide degradation on the conformational relationships between the molecular structure and bioactivities, such as antioxidant, antitumor, and immunomodulatory activities, are also discussed. Finally, we summarize the prospects and current challenges for the partial degradation of polysaccharides. This review will be of great value for the scientific elucidation of polysaccharide fine structures and potential applications.

Atractylodes lancea Rhizome Polysaccharide Alleviates Immunosuppression and Intestinal Mucosal Injury in Mice Treated with Cyclophosphamide

Plant-derived polysaccharides, such as Atractylodes lancea rhizome polysaccharide (ALP), are good immune regulators. However, the immune regulatory mechanism of the ALP is unknown. This study aimed to evaluate the effects of ALP on the intestinal mucosal barrier and intestinal mucosal immunity of immunosuppressed mice. We also compared the activity of raw Atractylodes lancea rhizome polysaccharide (SALP) with wheat bran processed bran-fried Atractylodes lancea rhizome polysaccharide (FALP; both at 1.2 g/kg/d for mice). Our results showed that ALP effectively increased the immune organ index and blood cell count, stimulated the secretion of cytokines, and promoted the expression of occludin and zonula occludens-1 (ZO-1). ALP also promoted the expression of T cells and the secretion of sIgA. Furthermore, ALP alleviated the gut microbiota disorder in Cy-treated mice and increased the relative abundances of Lactobacillus and Faecalibaculum. ALP reversed the decrease in the level of SCFAs and promoted the expression of G protein-coupled receptor 43 (GPR43). To our knowledge, this study was the first to explore how the ALP protects the intestinal mucosal barrier and enhances intestinal mucosal immunity by alleviating the gut microbiota imbalance and metabolic disorders of SCFAs. FALP was more therapeutic than SALP, suggesting that FALP could be developed as a promising functional food component.

Structural Characterization and Anti-inflammatory Activities of Anticomplementary Polysaccharides from Rhododendron principis

Rhododendron principis leaves have been used as "Dama", a Traditional Tibetan Medicine for treating inflammatory diseases. R. principis crude polysaccharides with anticomplementary activity demonstrated promising anti-inflammatory effects on acute lung injury induced by lipopolysaccharide. R. principis crude polysaccharides significantly decreased the levels of TNF-α and interleukin-6 in both serum and blood and bronchoalveolar lavage fluid in lipopolysaccharide-induced acute lung injury mice by intragastric administration (100 mg/kg). A heteropolysaccharide, ZNDHP, was obtained from R. principis crude polysaccharides with successive anticomplementary activity-guided separation. ZNDHP was characterized as a branched neutral polysaccharide with a backbone composed of → 2)-β-Glcp-(1→, → 2,6)-α-Glcp-(1→, → 6,3)-β-Galp-(1→, → 2,6)-α-Galp-(1→, → 6,2)-β-Glcp-(1→, → 4)-α-Glcp-(1→, → 5)-β-Araf-(1→, → 3,5)-α-Araf-(1→, and → 4,6)-β-Manp-(1→, and the backbone structure was further confirmed by partial acid hydrolysis. In addition to anticomplementary and antioxidant activities, ZNDHP exhibited potent anti-inflammatory activity by significantly inhibiting the secretion of nitric oxide, TNF-α, interleukin-6, and interleukin-1β of lipopolysaccharide-treated RAW 264.7 cells. However, all of these activities decreased greatly after partially hydrolyzing, indicating the importance of the multibranched structure for its bioactivity. Therefore, ZNDHP might be an important component of R. principis for treating inflammation.

Structural characterization and anti-inflammatory activity of a novel polysaccharide PKP2-1 from Polygonatum kingianum

Introduction

This study aimed to investigate the structure characterization and antiinflammatory activity of a novel polysaccharide, PKP2-1, from the rhizomes of Polygonatum kingianum Coll. and Hemsl.

Methods

We isolated a novel polysaccharide, PKP2-1, from the rhizomes of Polygonatum kingianum Coll. and Hemsl. for the first time, which was then successively purified through hot-water extraction, 80% alcohol precipitation, anion exchange and gel permeation chromatography. The in vitro anti-inflammatory activity of PKP2-1 in MH7A cells was assessed using a CCK-8 kit assay.

Results

Monosaccharide composition assay revealed that PKP2-1 was mainly composed of glucose, galactose, mannose, and glucuronic acid at an approximate molar ratio of 6:2:2:1. It had a molecular weight of approximately 17.34 kDa. Structural investigation revealed that the backbone of PKP2-1 consisted of (→2, 3)-α-D-Galp(4→, →2)-α-D-Manp(3→, →2)-β-D-Glcp(4→) and α-D-Glcp(3→) residues with side chains (→2)-β-D-Glcp(4→, →1)-α-D-Galp(4→) and α-D-Glcp(3→) branches located at O-3 position of (→2, 3)-α-D-Galp(4→). The in vitro anti-inflammatory activity of PKP2-1 in MH7A cells revealed that PKP2-1 could reduce the expression of IL-11β and IL-6, increase the expression of IL-10 and induce apoptosis of synovial fibroblasts.

Conclusion

The PKP2-1 could inhibit MH7A cell growth and potentially be exploited as an anti-inflammatory agent.

Purification, Characterization and Bioactivities of Polysaccharides Extracted from Safflower (Carthamus tinctorius L.)

Polysaccharides are the main bioactive components in safflower. In this study, safflower polysaccharides (SPs) were extracted by ultrasonic assisted extraction, and four purified safflower polysaccharide fractions (named SSP1, SSP2, SSP3, and SSP4, respectively) were obtained. The physicochemical properties and in vitro physiological activities of the four fractions were investigated. The molecular weights (M_W) of the SSPs were 38.03 kDa, 43.17 kDa, 54.49 kDa, and 76.92 kDa, respectively. Glucuronic acid, galactose acid, glucose, galactose, and arabinose were the main monosaccharides. The Fourier transform infrared spectroscopy (FT-IR) indicated that the polysaccharides had α- and β-glycosidic bonds. Nuclear magnetic resonance (NMR) analysis showed that SSP1 had 6 different types of glycosidic bonds, while SSP3 had 8 different types. SSP3 exhibited relatively higher ABTS⁺ scavenging activity, Fe⁺³-reduction activity, and antiproliferative activity. The results will offer a theoretical framework for the use of SPs in the industry of functional foods and medications.

The effect of structure and preparation method on the bioactivity of polysaccharides from plants and fungi

Polysaccharides are not only the main components in the cell walls of plants and fungi, but also a structure that supports and protects cells. In the process of obtaining polysaccharides from raw materials containing cell walls, the polysaccharides on the cell walls are the products and also a factor that affects the extraction rate. Polysaccharides derived from plants and fungi have mild characteristics and exhibit various biological activities. The biological activity of polysaccharides is related to their chemical structure. This review summarizes the effects of the physicochemical properties and structure of polysaccharides, from cell walls in raw materials, that have an impact on their biological activities, including molecular weight, monosaccharide composition, chain structure, and uronic acid content. Also, the structure of certain natural polysaccharides limits their biological activity. Chemical modification and degradation of these structures can enhance the pharmacological properties of natural polysaccharides to a certain extent. At the same time, the processing method affects the structure and yield of polysaccharides on the cell wall and in the cell. The extraction and purification methods are summarized, and the effects of preparation methods on the structure and physiological effects of polysaccharides from plants and fungi are discussed.

Isolation of a New Polysaccharide from Dandelion Leaves and Evaluation of Its Antioxidant, Antibacterial, and Anticancer Activities

Dandelion, in China, has a long history as a medicinal and edible plant, and possesses high nutritional and medical value. The present study aimed to isolate a new polysaccharide (DLP-3) from dandelion leaves and to evaluate its antioxidant, antibacterial, and anticancer activities. The structure of DLP-3 was analyzed using HPLC, FT-IR, SEM, GC-MS, and NMR spectroscopy. DLP-3 mainly consisted of Man, Rha, GlcA, Glc, Gal, and Ara with molar ratios of 2.32, 0.87, 1.21, 3.84, 1.00, and 1.05, respectively, with a molecular weight of 43.2 kDa. The main linkages of DLP-3 contained (1→4)-α-d-Glc, (1→4,6)-α-d-Glc, (1→6)-α-d-Gal, (1→2)-α-d-Man, (1→4)-α-d-Man, β-l-Ara-(1→, and α-l-Rha-(1→. DLP-3 exhibited a smooth surface, purely flake-like structure, and a triple helix conformation. Moreover, DLP-3 presented obvious antioxidant and antibacterial activities in a concentration-dependent manner. DLP-3 showed significant anticancer activities by inhibiting tumor cell proliferation. These findings provide a theoretical basis for the application of DLP-3 as a natural functional active substance in functional foods.

Structural characterization and immunoregulatory activity of a neutral polysaccharide from the roots of Apocynum venetum L

The structural characteristics and immunoregulatory activities of neutral heteropolysaccharide (AVRP-N) separated from the roots of Apocynum venetum L. were extensively investigated. The results showed that the weight average molecular mass (Mw) of AVRP-N was 6.430 × 10³ Da. Moreover, the backbone is composed of natural acetylated (1 → 4)-β-D-Man and (1 → 5)-α-L-Ara domains. The mannan is composed of →4)-β-D-Manp-(1→, →4)-β-D-Glcp-(1→, and the terminal group α-D-Galp-(1→ attached to →4,6)-β-D-Manp-(1→ at O-6. Araban is composed of →5)-α-L-Araf-(1→; the terminal group α-L-Araf-(1→attached to→2,3,5)-α-L-Araf-(1→ at O-2, O-3 and →3,5)-α-L-Araf-(1→ at O-3. In addition, the senior structure shows that AVRP-N has a triple-helix conformation. Furthermore, AVRP-N exhibited immunomodulatory effects, which could significantly regulate the proliferation of mouse splenic lymphocytes by enhancing the secretion of the cytokines (IFN-γ, IL-2, IL-4, and IL-10). Our results provide new structural and immunoregulatory information for natural polysaccharides derived from Apocynum venetum L.

Effects of Sparassis latifolia neutral polysaccharide on immune activity via TLR4-mediated MyD88-dependent and independent signaling pathways in RAW264.7 macrophages

Background

Sparassis latifolia (S. latifolia) is a precious edible fungus with multiple biological activities. To date, no study has been investigated the underlying molecular mechanism of immunoregulation caused by the neutral polysaccharide of S. latifolia.

Materials and methods

To investigate immunomodulatory mechanism of S. latifolia neutral polysaccharide (SLNP), SLNP was obtained from S. latifolia and its structure, immune receptors and regulation mechanism were studied.

Results

S. latifolia neutral polysaccharide consisted of arabinose, galactose, glucose, xylose, and mannose with a molar ratio of 6:12:63:10:5. SLNP was a pyran polysaccharide with a relative molecular weight of 3.2 × 105 Da. SLNP promoted the proliferation of RAW264.7, which further induced the secretions of nitric oxide, TNF-α, IL-6, and IFN-β, and upregulated the immune receptor TLR4 expression. Moreover, SLNP increased remarkably the levels of TRAF6, IRF3, JNK, ERK, p38, and p38 mRNA and protein mediated by TLR4.

Conclusion

S. latifolia neutral polysaccharide regulated the immune function of RAW264.7 through MyD88-dependent and -independent signaling pathways mediated by TLR4 receptor, which suggests that SLNP is a new immunomodulator.

Antitumor effect of a polysaccharide from Pseudostellaria heterophylla through reversing tumor-associated macrophages phenotype

Tumor-associated macrophages (TAMs), which are predominant tumor-infiltrating immune cells in the tumor microenvironment, participate in promoting the occurrence and metastasis of tumor cells. Reprogramming TAMs has become a promising immunotherapeutic approach for novel cancer treatments. In this study, a homogeneous polysaccharide (PHP-1) was obtained from Pseudostellaria heterophylla, and its antitumor and immunological activities, as well as the underlying molecular mechanisms were explored. These findings suggested that PHP-1 can switch M2 macrophages to the M1 type, thereby promoting tumor cell apoptosis in vitro. In addition, PHP-1 can modulate the TAMs phenotype, maintain the CD4⁺/CD8⁺ lymphocyte balance, and exert antitumor effects in H22 tumor-bearing mice. Mechanistically, PHP-1 is recognized by the TLR4 receptor, promotes Ca²⁺ release, and activates the NF-κB and MAPK signaling pathways to reset the M2-type macrophages. These findings indicate that PHP-1 from P. heterophylla can function as a tumor immunotherapeutic modulator.

Acetylation Modification, Characterization, and Anticomplementary Activity of Polysaccharides from Rhododendron dauricum Leaves

This study focuses on the acetylation modification of polysaccharides from Rhododendron dauricum leaves (RDPs) with a high degree of substitution (DS) and then discusses their characterization and biological activity. The optimum acetylation conditions of RDPs were optimized by response surface methodology, which were reaction time 3 h, reaction temperature 50 °C, and the liquid-solid ratio 16 mL/g. Under the optima schemes, two eco-friendly acetylated polysaccharides from R. dauricum leaves (AcRDP-1 with DS of 0.439 ± 0.025 and AcRDP-2 with DS of 0.445 ± 0.022) were prepared. The results of structural characterization showed that the AcRDP-1 (9.3525 × 10³ kDa) and AcRDP-2 (4.7016 × 10³ kDa) were composed of mannose, glucose, galactose, and arabinose with molar ratios of 1.00:5.01:1.17:0.15 and 1.00:4.47:2.39:0.88, respectively. Compared with unmodified polysaccharides, the arabinose content and molecular weight of the two acetylated polysaccharides decreased, and their triple helix conformation disappeared, and further improved their anticomplementary activity. The two acetylated polysaccharides showed stronger a complement inhibition effect than the positive drug by blocking C2, C3, C4, C5, C9, and factor B targets in the classical and alternative pathways. This research indicated that acetylation modification could effectively enhance the anticomplementary activity of RDPs, which is beneficial for the development and utilization of R. dauricum leaves.

Isolation, characterization and anticomplementary activity of polysaccharides from the rhizomes of Belamcanda chinensis (L.) DC

The polysaccharides from the rhizomes of Belamcanda chinensis (L.) DC. (BCPs) were obtained by optimal water extraction (extraction temperature 84℃, liquid to solid ratio 42 mL/g and extraction time 100 min), the extraction yield of BCPs was 23.01 ± 0.27% (n=3). Furthermore, two novel polysaccharides (BCP-A1 and BCP-B1) were purified by column chromatography. The BCP-A1 (6.0820×104 kDa) was composed of β -D-Manp-(1→, β -D-Glcp-(1→, →4)-α-D-Galp-(1→ and →3,4)- β-D-Galp-(1→, and BCP-B1 (2.2744×104 kDa) was composed of →5)-α-L-Araf -(1→, β -D-Manp-(1→, β-D-Glcp-(1→, →4)-α-D-Glcp, →4)-α-D-Galp-(1→, →4)-α-D-Galp A-(1→ and →3,4)-β-D-Galp-(1→. In anticomplementary experiments, BCP-A1 (CH50: 0.009 ± 0.003 mg/mL; AP50: 0.015 ± 0.003 mg/mL) and BCP-B1 (CH50: 0.004 ± 0.001 mg/mL; AP50: 0.028 ± 0.005 mg/mL) exhibited potent anticomplementary activity, and acted on C2-, C4- and Factor B components. Our study provides a foundation for BCP-A1 and BCP-B1 as potential complement inhibitors to treat diseases involving with excessive activation of the complement system.

Two Natural Flavonoid Substituted Polysaccharides from Tamarix chinensis: Structural Characterization and Anticomplement Activities

Two novel natural flavonoid substituted polysaccharides (MBAP-1 and MBAP-2) were obtained from Tamarix chinensis Lour. and characterized by HPGPC, methylation, ultra-high-performance liquid chromatography-ion trap tandem mass spectrometry (UPLC-IT-MSⁿ), and NMR analysis. The results showed that MBAP-1 was a homogenous heteropolysaccharide with a backbone of 4)-β-d-Glcp-(1→ and →3,4,6)-β-d-Glcp-(1→. MBAP-2 was also a homogenous polysaccharide which possessed a backbone of →3)-α-d-Glcp-(1→, →4)-β-d-Glcp-(1→ and →3,4)-β-d-Glcp-2-OMe-(1→. Both the two polysaccharides were substituted by quercetin and exhibited anticomplement activities in vitro. However, MBAP-1 (CH₅₀: 0.075 ± 0.004 mg/mL) was more potent than MBAP-2 (CH₅₀: 0.249 ± 0.006 mg/mL) and its reduced product, MBAP-1R (CH₅₀: 0.207 ± 0.008 mg/mL), indicating that multiple monosaccharides and uronic acids might contribute to the anticomplement activity of the flavonoid substituted polysaccharides of T. chinensis. Furthermore, the antioxidant activity of MBAP-1 was also more potent than that of MBAP-2. In conclusion, these two flavonoid substituted polysaccharides from T. chinensis were found to be potential oxidant and complement inhibitors.

Isolation and Structural Characterization of Two Polysaccharides from Dracocephalum moldavica and Their Anti-Complementary Activity

The two novel polysaccharides, DMP-1 and DMP-2, with molecular weights of 4.1553×10⁵  kDa and 1.9764×10⁵  kDa, respectively, were isolated from Dracocephalum moldavica. The structural characterization indicated that DMP-1 and DMP-2 shared a similar backbone consisting of →5)-Araf-(1→, Manp-(1→, Glcp-(1→, →2)-Manp-(1→, →6)-Glcp-(1→ and →3,6)-Galp-(1→ with a different molar ratios and triple-helix structures with α- and β-type glycosidic bonds. The anti-complementary activity evaluation showed that DMP-1 and DMP-2 had strong complement inhibition through the classical pathway (CP), alternative pathway (AP) and lectin pathway (LP). Mechanistic studies indicated that DMP-1 can block the activation cascade of the complement system by targeting C2, C3, C5, C9, Factor B and Factor P, and that DMP-2 inhibited complement activation by blocking C2, C3, C4, C5, C9 and Factor B.

Structural characterisation and antitumor activity against non-small cell lung cancer of polysaccharides from Sanghuangporus vaninii

The medicinal fungus Sanghuangporus vaninii can be cultivated in large scale and has outstanding antitumour activity. In this study, water-soluble S. vaninii polysaccharides (SVPs) were extracted from fruiting bodies. Four polysaccharide sub-fractions (SVP-W, SVP-1, SVP-2 and SVP-3) were isolated, with molecular weights from 90.50 kDa to 261.70 kDa, and all inhibited the proliferation of non-small cell lung cancer cell lines A549, 95-D and NCI-H460, especially the acidic SVP-1. SVP-1 affected cell morphology and colony formation in NCI-H460 cells. It also promoted cell apoptosis following nuclear fluorescence staining and flow cytometry. Methylation and nuclear magnetic resonance analyses revealed that SVP-1 is a heteroglycan with the main chain →4)-β-D-Glcp-(1 → 6)-β-D-Glcp-(1 → 6)-α-D-Galp-(1 → 6)-β-D-Glcp-(1→, and the branched chain α-D-Manp-(1 → 2)-α-D-Manp-(1 → 3)-β-D-Glcp-(1 → 3,6)-β-D-Glcp-(1→. The findings indicate that this natural acidic polysaccharide has potential for non-small cell lung cancer therapy.

Ophiocordyceps lanpingensis polysaccharides alleviate chronic kidney disease through MAPK/NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ophiocordyceps lanpingensis (O. lanpingensis) is a traditional ethno-medicine distributed in Eastern Himalayas, which has been used by local minorities to prevent and treat urinary diseases for hundreds of years. However, the corresponding active components and related pharmacological mechanism of such medication are not clear yet.

AIMS OF THE STUDY

This study was performed to investigate the effects and potential mechanisms of O. lanpingensis polysaccharides (OLP) in the treatment of chronic kidney disease (CKD) based on our previous research results.

MATERIALS AND METHODS

Methylation analysis was used to investigate the monosaccharide composition and glycosidic linkages in OLP. The animals were divided into the control group, CKD model group, losartan group and three different doses of OLP groups. The CKD mouse model was established by the adenine gavage. The histological changes of renal tissue were observed by Hematoxylin-eosin and Masson staining. Biochemical indicators, including blood urea nitrogen (BUN), serum creatinine (Scr), serum phosphorus (P), plasma calcium (Ca), reactive oxygen species (ROS), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and malondialdehyde (MDA) were measured to evaluate the alleviation of CKD by OLP. Moreover, the expression levels of a series of cytokines related to the inflammation, apoptosis and fibrosis were analyzed to explore the possible mechanisms of OLP to treat CKD.

RESULTS

OLP is composed of three kinds of monosaccharides. There are eight kinds of glycosidic linkages in OLP, among which →4)-Glcp-(1→ is the main linkage. OLP could significantly attenuate CKD in mice and the tubulointerstitial damage was recovered to almost normal after the treatment of OLP. Compared with the CKD model group, the levels of Scr, BUN, MDA, P in OLP treatment groups were significantly decreased; and the levels of SOD and Ca were increased after OLP treatment. Furthermore, OLP could reduce the oxidative stress of the renal tissues, decrease the expression levels of pro-inflammatory factors through TLR4-mediated MAPK and NF-κB pathway, inhibit the apoptosis of renal cells by MAPK pathway, and relieve the renal fibrosis by down-regulating the expression of TGF-β1.

CONCLUSIONS

OLP is composed of three kinds of monosaccharides and →4)-Glcp-(1→ is the main glycosidic linkage in the polysaccharide. OLP could ameliorate CKD in mice by declining the oxidative stress, inflammation, apoptosis and fibrosis in the kidneys. The study provided some evidences for the potential application of OLP in alleviating CKD.

Natural products provide a new perspective for anti-complement treatment of severe COVID-19: a review

Exaggerated immune response and cytokine storm are accounted for the severity of COVID-19, including organ dysfunction, especially progressive respiratory failure and generalized coagulopathy. Uncontrolled activation of complement contributes to acute and chronic inflammation, the generation of cytokine storm, intravascular coagulation and cell/tissue damage, which may be a favorable target for the treatment of multiple organ failure and reduction of mortality in critically ill patients with COVID-19. Cytokine storm suppression therapy can alleviate the symptoms of critically ill patients to some extent, but as a remedial etiological measure, its long-term efficacy is still questionable. Anti-complement therapy has undoubtedly become an important hotspot in the upstream regulation of cytokine storm. However, chemosynthetic complement inhibitors are expensive, and their drug resistance and long-term side effects require further investigation. New complement inhibitors with high efficiency and low toxicity can be obtained from natural products at low development cost. This paper puts forward some insights of the development of natural anti-complement products in traditional Chinese medicine, that may provide a bright perspective for suppressing cytokine storm in critically ill patients with COVID-19.

A neutral polysaccharide from Ophiocordyceps lanpingensis restrains cisplatin-induced nephrotoxicity

Ophiocordyceps lanpingensis is an edible mushroom distributed over the south-eastern part of the Tibet Plateau, which is also recognized as an effective ethnomedicine to alleviate diseases. This study explored the effects of a kind of Ophiocordyceps lanpingensis neutral polysaccharide (ONP) on RAW264.7 macrophages and cisplatin-induced nephrotoxicity. The results showed that ONP relieved the inflammatory response of RAW264.7 macrophages by increasing the expression level of anti-inflammatory factor IL-10. Furthermore, ONP treatment significantly prolonged the survival of the mice treated by cisplatin through decelerating pathological progress and alleviating damaged functions of the kidneys. Compared with the cisplatin group, ONP reduced the oxidative stress of the renal cells and the expression levels of pro-inflammatory factors. Apoptosis of renal cells was also weakened in the ONP treatment group. These findings indicated that ONP alleviated cisplatin nephrotoxicity mainly by inhibiting oxidative stress, inflammation, and apoptosis in the kidneys, underscoring the potential of ONP supplementation to alleviate the side effects of cisplatin chemotherapy.

Characterization of a polysaccharide from the medicinal lichen, Usnea longissima, and its immunostimulating effect in vivo

A polysaccharide, CSL-0.1, was isolated from the medicinal lichen, Usnea longissima. CSL-0.1 was a neutral rhamnose-containing glucogalactomannan with a molecular weight of 7.86 × 104 Da. The polysaccharide had a core mannan structure with (1 → 6)-α-d-Manp units as the main chain and was substituted at the O-2 positions with side chains containing (1 → 2)-α-d-Manp residue, [3)-α-Glcp(1 → 4)-α-Glcp(1→] and 6-O-substituted β-d-Galf units. 2-O- and 2,3-di-O-substituted Rhap units. The effects of CSL-0.1 on intestinal immunity and antioxidant activity were evaluated. CSL-0.1 increased the spleen and thymus indices in a dose-dependent manner and conferred immunomodulation on reversing the Th1/Th2-related cytokine imbalance in cyclophosphamide (CP)-induced immunosuppressed mice. CSL-0.1 could also enhance the levels of secretory immunoglobulin A in CP-injected mice. Additionally, the antioxidant levels in the liver and intestine of the mice were increased 20%-50% after intragastric injection by CSL-0.1.

Degradation models, structure, rheological properties and protective effects on erythrocyte hemolysis of the polysaccharides from Ribes nigrum L

The polysaccharides from blackcurrant (Ribes nigrum L.) fruits were degraded by ultrasonic irradiation. Results showed that viscosity-average molecular weight decreased with increasing ultrasonic time or power. The degradation was fitted to the second-order kinetics model and midpoint chain scission model. Gas chromatographic analysis demonstrated that the native polysaccharide and three degraded polysaccharides were composed of the same monosaccharides but in different ratios. Fourier transform infrared and nuclear magnetic resonance spectroscopic analyses revealed the presence of α-, β-pyranose rings and the same six sugar residues in the four blackcurrant polysaccharides. Compared to the native polysaccharide, three degraded polysaccharides displayed better rheological properties and stronger protective effects against erythrocyte hemolysis. Collectively, the results support the potential utility of blackcurrant polysaccharides as natural antioxidants.

Molecular Identification Based on Chloroplast Sequences and Anti-complementary Activity Comparison of Juniperus Samples from the Qinghai-Tibet Plateau

Juniperus (Cupressaceae, Pinales) plants are widely distributed in the Qinghai-Tibet Plateau of China. The leaves and twigs of at least 8 Juniperus species (J. pingii, J. pingii var. wilsonii, J. squamata, J. recurva var. coxii, J. saltuaria, J. indica, J. tibetica and J. convallium var. microsperma) have been used as the Tibetan medicine Xuba. At present, it is difficult to distinguish among the original species of Xuba based only on their similar morphological characteristics. However, in our previous studies, 4 Xuba samples from different Juniperus species exhibited significant differences in both anticomplementary activity in vitro and anti-inflammatory effects on acute lung injury in vivo. To identify the effective original species of Xuba reliably, in this study, we developed a sequencing-based DNA molecular technology to distinguish 14 populations of 8 Juniperus species collected from Tibet region, using trnS-G, trnD - T, and petN-psbM genomic regions to build phylogenetic trees. In addition, their anticomplementary activities were evaluated. The results showed that combined sequence of these 3 genomic regions could identify 8 Juniperus species clearly and clustered individuals of one species but from different locations, whichever phylogenetic tree was constructed. Moreover, the anticomplementary activities of the 8 species were clustered into 2 groups. Among them, J. saltuaria and J. recurva var. coxii, which formed an independent branch apart from the other 6 species in phylogenetic trees, were the most potent (CH₅₀: 0.029 - 0.032 mg/mL). Consequently, DNA identification of Juniperus using the combined sequence could provide beneficial guidance for further efficacy evaluation and quality control of Xuba.

Structural characteristics and anti-tumor/-oxidant activity in vitro of an acidic polysaccharide from Gynostemma pentaphyllum

In this paper, a novel acidic polysaccharide (CPS-1) was successively prepared from Gynostemma pentaphyllum using hot water isolation method to explore its antitumor and antioxidant activities. Structural characteristics of CPS-1 were evaluated by SEM, HPGPC, HPAEC-PAD, FT-IR, and NMR. The results indicated: CPS-1 was mainly composed of Ara, Gal, Glc, Xyl, Man, GalA and GlcA in a molar ratio of 1.23:2.14:0.67:0.2:0.29:0.16:0.04 with molecular weight of 3297 kDa. Combining with the results of FT-IR and NMR, it was inferred that CPS-1 was mainly possessed the five main linkages including α-D-Ara, α-D-Gal, α-D-Man, α-D-Xyl and β-D-Glc. Furthermore, MTT results exhibited that the IC₅₀ value of CPS-1 for inhibitive effect on SPC-A-1 and MGC-803 cells for 24 h were 284.36 and 365.27 μg/mL, respectively. Microscopic observations showed that the cells exhibited significant apoptotic characteristics, such as cell shrinkage, the decreased of cell adherence and the appearance of apoptotic bodies. It was shown that CPS-1 had significant anti-tumor activity. In addition, the ability of CPS-1 to scavenge superoxide radical, ABTS and DPPH radicals was also enhanced with the increased of concentration. Therefore, it was revealed that CPS-1 might be used as a natural anticancer and antioxidant component.