Polysaccharides from Hedyotis diffusa enhance the antitumor activities of cytokine-induced killer cells

Anti-liver cancer effects and mechanisms and its application in nano DDS of polysaccharides: A review

Liver cancer is the third leading cause of cancer death, with high incidence and poor treatment effect. In recent years, polysaccharides have attracted more and more attention in the research field of anti-liver cancer because of their high efficiency, low toxicity, good biocompatibility, wide sources and low cost. Polysaccharides have been proven to have good anti-liver cancer activity. In this paper, the pathways and molecular mechanisms of polysaccharides against liver cancer were reviewed in detail. Polysaccharides exert anti-liver cancer activity by blocking cell cycle, inducing apoptosis, regulating immunity, inhibiting cancer cell metastasis, inhibiting tumor angiogenesis and so on. The primary structure and chain conformation of polysaccharides have an important influence on their anti-liver cancer activity. Structural modification enhanced the anti-liver cancer activity of polysaccharides. Polysaccharides have good attenuated and synergistic effects on chemotherapy drugs. Polysaccharides can be used as functional carriers to construct intelligent nano drug delivery systems (DDS) targeting liver cancer. This review can provide theoretical support for the further development and application of polysaccharides in the field of anti-liver cancer, and provide theoretical reference and clues for relevant researchers in food, nutrition, medicine and other fields.

A Reverse Thinking Based on Partially Methylated Aldononitrile Acetates to Analyze Glycoside Linkages of Polysaccharides Using Liquid Chromatography-Multiple Reaction Monitoring Mass Spectrometry

Glycoside linkage analyses of medicine and food homologous plant polysaccharides have always been a key point and a difficulty of structural characterization. The gas chromatography-mass spectrometry (GC-MS) method is one of the commonly used traditional techniques to determine glycoside linkages via partially methylated alditol acetates and aldononitrile acetates (PMAAs and PMANs). Due to the simplicity of derivatization and the highly structural asymmetry of PMANs, reverse thinking is proposed using liquid chromatography-electrospray ionization-multiple reaction monitoring mass spectrometry (LC-ESI-MRM-MS) for the first time to directly determine the neutral and acidic glycosyl linkages of polysaccharides. The complete characterization of glycoside linkages deduced from PMANs was achieved using a combination of tR values, characteristic MRM ion pairs, diagnostic ESI+-MS/MS fragmentation ions (DFIs), and optimal collision energy (OCE). The DFI and OCE parameters were confirmed to be effective for the auxiliary discrimination of some isomers of the PMANs. The practicality of LC-ESI+-MRM-MS was further verified by analyzing the glycoside linkages of polysaccharides in five medicine and food homologous plants. This method can serve as an alternative to GC-MS for the simultaneous determination of neutral and acidic glycosyl linkages in polysaccharides.

Mechanism of Qizhen decoction-mediated maturation of DC cells to activate the IL-12/JAK2/STAT4 pathway to sensitise PD-1 inhibitors in the treatment of colorectal cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine has been utilized to treat colorectal cancer (CRC). Qizhen decoction (QZD), a potential compound prescription of traditional Chinese medicine, possesses multiple biological activities. It has been used to treat CRC in clinical practice and has been proven to be effective.

AIM OF THE STUDY

To investigate the impact of QZD supported by intestinal flora in combination with PD-1 inhibitor on colorectal cancer, and to elucidate the mechanism by which QZD enhances the sensitivity of PD-1 inhibitor against colorectal cancer.

MATERIALS AND METHODS

Observation of Intestinal Flora Mediating the Effect of QZD Combined with PD-1 Inhibitor in the Treatment of Colorectal Cancer. We used Flow cytometry and qPCR to detect the effect of QZD combined with PD-1 inhibitor on the activation of effector T cells in a wild mouse model of colorectal cancer. In wild and germ-free mouse models, the differences in inflammatory factors, pathological change, body mass, colorectal length, and tumour load were observed. In the study of the mechanism of QZD combined with PD-1 inhibitor in the treatment of colorectal cancer, the study evaluated the abundance of Akkermansia, the phenotypes of effector T cells and DC cells, as well as inflammatory factors in each group of mice to determine whether Akkermansia played a role in activating DC cells. Based on the JAK2/TYK2/STAT4 pathway, the mechanism of PD-1 inhibitor sensitisation by QZD in colorectal cancer was further investigated.

RESULTS

We found that QZD combined with PD-1 inhibitor could improve the therapeutic effect on colorectal cancer by inducing more critical immune functions. QZD promotes increased Akkermansia abundance in the gut. Akkermansia promotes maturation of DC cells, and mature DC cells activate the IL-12/JAK2/STAT4 pathway, which significantly activates effector T cells. Akkermansia is key to QZD combined with PD-1 inhibitor-mediated immunity exerting a therapeutic effect on colorectal cancer.

CONCLUSION

The mechanism of action of the QZD sensitizing PD-1 inhibitor is to promote the maturation of DC cells to release IL-12 and activate the JAK2/STAT4 pathway to induce effector T cell activation by increasing the abundance of Akkermansia.

An anticomplement homogeneous polysaccharide from Hedyotis diffusa attenuates lipopolysaccharide-induced acute lung injury and inhibits neutrophil extracellular trap formation

BACKGROUND

Owing to the involvement of the overactivated complement system in acute lung injury (ALI) development, anticomplement components may attenuate ALI. Hedyotis diffusa is a traditional Chinese medicine for treating lung heat and its crude polysaccharides (HDP) exhibit significant anticomplement activity in vitro.

PURPOSE

To obtain an anticomplement homogeneous polysaccharide from HDP and verify its therapeutic effect and mechanism on ALI.

METHODS

Diethylaminoethyl-52 (DEAE-52) cellulose and gel permeation columns were used to isolate a homogeneous polysaccharide HD-PS-3, which was then characterized using nuclear magnetic resonance (NMR) and methylation analysis. In vitro, the anticomplement activities of HD-PS-3 through classical and alternative pathways were determined using a hemolytic test. The therapeutic effects of HDP and HD-PS-3 on ALI were evaluated in lipopolysaccharide (LPS) intratracheal instilled mice. Hematoxylin and eosin (H&E) staining, enzyme-linked immunosorbent assay (ELISA), and immunohistochemical staining were used to assess histological changes, measure cytokine levels, and evaluate the degree of complement component 3c (C3c) deposition and neutrophil infiltration, respectively. ELISA, western blotting, and immunofluorescence were used to analyze neutrophil extracellular trap (NET) formation.

RESULTS

From HDP, 1.5 g of the homogeneous polysaccharide HD-PS-3 was obtained. HD-PS-3 was an acidic heteropolysaccharide with an acetyl group, which was composed of →4,6)-α-Glcp-(1→, →3,4)-α-Glcp-(1→, →4)-α-Glcp-(1→, →4,6)-α-Galp-(1→, →5)-α-Araf-(1→, α-Rhap-(1→, α-Araf-(1→, α-GlcpA-(1→, →4)-β-Manp-(1→, β-Manp-(1→ and →3)-β-Manp-(1→. The in vitro results suggest that HD-PS-3 exhibited anticomplement activity with CH₅₀ and AP₅₀ values of 115 ± 12 μg/ml and 307 ± 11 μg/ml, respectively. After confirming the efficacy of HDP (200 mg/kg) in attenuating lung injury, the effect of HD-PS-3 on ALI was also investigated. HD-PS-3 (75 and 150 mg/kg) attenuated LPS-induced ALI as well, evidenced by lung pathology, lung injury scores, protein concentration, leukocyte counts, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) contents in bronchoalveolar lavage fluid (BALF). Mechanistically, HD-PS-3 inhibited complement activation, manifested in reduced pulmonary C3c deposition in lung tissue and complement component 3a (C3a) content in BALF. Neutrophil recruitment was also reduced by HD-PS-3, with significantly reduced pulmonary neutrophil infiltration and lower levels of C-X-C motif chemokine ligand 1 (CXCL1) and myeloperoxidase (MPO) in BALF. In addition, HD-PS-3 reduced the levels of MPO-DNA complex in BALF, decreased citrullinated histone H3 (Cit H3) expression and NET formation (colocalization of MPO, Cit H3, and DNA) in lung tissue.

CONCLUSION

An anticomplement homogeneous polysaccharide HD-PS-3 was isolated from H. diffusa. HD-PS-3 exhibited a therapeutic effect against ALI, and the mechanism might be related to its inhibitory effects on complement activation, neutrophil recruitment, and NET formation.

The Characteristics and Mortality of Chinese Herbal Medicine Users among Newly Diagnosed Inoperable Huge Hepatocellular Carcinoma (≥10 cm) Patients: A Retrospective Cohort Study with Exploration of Core Herbs

For patients with inoperable huge hepatocellular carcinoma (H-HCC, tumor size ≥10 cm), treatment options are limited. This study aimed to evaluate the characteristics and outcomes of patients with H-HCC who use Chinese herbal medicine (CHM). Multi-institutional cohort data were obtained from the Chang Gung Research Database (CGRD) between 1 January 2002 and 31 December 2018. All patients were followed up for 3 years or until the occurrence of death. Characteristics of CHM users and risk of all-cause mortality were assessed, and core CHMs with potential pharmacologic pathways were explored. Among 1618 patients, clinical features of CHM users (88) and nonusers (1530) were similar except for lower serum α-fetoprotein (AFP) and higher serum albumin levels in CHM users. CHM users had significantly higher 3 year overall survival rates (15.0% vs. 9.7%) and 3 year liver-specific survival rates (13.4% vs. 10.7%), about 3 months longer median survival time, and lower risk of all-cause mortality. Core CHMs were discovered from the prescriptions, including Hedyotis diffusa Willd combined with Scutellaria barbata D.Don, Salvia miltiorrhiza Bunge., Curcuma longa L., Rheum palmatum L., and Astragalus mongholicus Bunge. CHM use appears safe and is possibly beneficial for inoperable H-HCC patients; however, further clinical trials are still required.

Emerging role of natural products in cancer immunotherapy

Cancer immunotherapy has become a new generation of anti-tumor treatment, but its indications still focus on several types of tumors that are sensitive to the immune system. Therefore, effective strategies that can expand its indications and enhance its efficiency become the key element for the further development of cancer immunotherapy. Natural products are reported to have this effect on cancer immunotherapy, including cancer vaccines, immune-check points inhibitors, and adoptive immune-cells therapy. And the mechanism of that is mainly attributed to the remodeling of the tumor-immunosuppressive microenvironment, which is the key factor that assists tumor to avoid the recognition and attack from immune system and cancer immunotherapy. Therefore, this review summarizes and concludes the natural products that reportedly improve cancer immunotherapy and investigates the mechanism. And we found that saponins, polysaccharides, and flavonoids are mainly three categories of natural products, which reflected significant effects combined with cancer immunotherapy through reversing the tumor-immunosuppressive microenvironment. Besides, this review also collected the studies about nano-technology used to improve the disadvantages of natural products. All of these studies showed the great potential of natural products in cancer immunotherapy.

Dose-dependent effects of Hedyotis diffusa extract on the pharmacokinetics of tamoxifen, 4-hydroxytamoxifen, and N-desmethyltamoxifen

Tamoxifen, a widely prescribed medication in premenopausal women diagnosed with hormone-dependent breast cancer, is potentially co-prescribed with Hedyotis diffusa (H. diffusa), particularly in Taiwan. However, no related report has investigated the drug-herb interaction of H. diffusa on the pharmacokinetics of tamoxifen and its metabolites. In the present study, male Sprague-Dawley rats were administered different doses of H. diffusa extract for 5 consecutive days prior to the administration of tamoxifen (10 mg/kg). A validated ultra-liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) system was developed to monitor tamoxifen, 4-hydroxytamoxifen, N-desmethyltamoxifen, and endoxifen in rat plasma. Pharmacokinetic results demonstrated that the area under curves (AUCs) of tamoxifen and the relative bioavailability (%) of tamoxifen were dose-dependently decreased (31-68%) by pre-treatment with H. diffusa extract (3 g/kg and 6 g/kg). In addition, the conversion ratio of 4-hydroxytamoxifen was downregulated (0.5-fold change) and the N-desmethyltamoxifen conversion ratio was upregulated (2-fold change) by high-dose H. diffusa extract. As a result, the relative bioavailability and biotransformation changes affect the clinical efficacy of tamoxifen treatment. These preclinical findings reveal a hitherto unreported interaction between tamoxifen and H. diffusa extract that has implications for their therapeutic efficacy in treating breast cancer.

A novel LC-MS/MS method for complete composition analysis of polysaccharides by aldononitrile acetate and multiple reaction monitoring

Carbohydrate analysis has always been a challenging task due to the occurrence of high polarity and multiple isomers. Aldoses are commonly analyzed by gas liquid chromatography (GLC) following aldononitrile acetate derivatization (AND). However, the GLC technique cannot be applied for the simultaneous determination of aldoses, ketoses, and uronic acids. In this study, a new method based on the combination of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and AND is developed for the complete characterization of monosaccharide composition (i.e., aldoses, ketoses, alditols, amino sugars, and uronic acids) in plant-derived polysaccharides. In addition to discussing the possible byproducts, the study optimizes the multiple reaction monitoring (MRM) parameters and LC conditions. The final separation of 17 carbohydrates is performed on a BEH Shield RP18 column (150 mm × 2.1 mm, 1.7 μm) within 25 min, without using any buffer salt. Notably, the complex polysaccharides extracted from Ligusticum chuanxiong, Platycodon grandiflorum, Cyathula officinalis Kuan, Juglans mandshurica Maxim, and Aralia elata (Miq.). Seem bud can be successfully characterized using the developed method. Overall, the results demonstrated that the newly established LC-MS/MS MRM method is more effective and powerful than the GLC-based methods reported previously, and it is more suitable for the analysis of highly complex natural polysaccharides, including complex pectins, fructosans, and glycoproteins.

Isolation, purification, structural characteristics, pharmacological activities, and combined action of Hedyotis diffusa polysaccharides: A review

Hedyotis diffusa polysaccharides, as the main component and an important bioactive substance of Hedyotis diffusa, are effective immunomodulators with various pharmacological activities, including antitumour, anti-inflammatory, antioxidant, anti-fatigue and immunity-enhancing activities. The total polysaccharides extracted from Hedyotis diffusa and Scutellaria barbata have great effects in treating liver cancer, gastric cancer, rectal cancer, glioma and nasopharyngeal carcinoma. Moreover, different materials and extraction methods result in differences in the structure and bioactivity of Hedyotis diffusa polysaccharides. Therefore, this paper summarizes the isolation, purification, structural characteristics, pharmacological activities, and combined action of Hedyotis diffusa polysaccharides to provide a reference for further study.

Antitumor potential of Hedyotis diffusa Willd: A systematic review of bioactive constituents and underlying molecular mechanisms

Cancer is a major cause of death in the world. Chemotherapy can extend the life of cancer patients to some extent, but the quality of life is reduced. Therefore, the quest for more efficient and less toxic medication strategies is still at the forefront of current research. Hedyotis diffusa Willd (HDW), a Chinese herb medicine, has received great attention in the past two decades and has been well documented in clinics for antitumor activity in a variety of human cancers. This review discussed a total of 58 different kinds of active antitumor components isolated from HDW, including iridoids, flavonoids, flavonol glycosides, anthraquinones, phenolic acids, and their derivatives, sterols, and volatile oils. Their antitumor activities include inhibition of tumor cell proliferation, induction of tumor cell apoptosis and tumor angiogenesis, regulation of the host immune response, anti-inflammatory and antioxidant, and protective autophagy. Besides, we provide up-to-date and systematic evidence for HDW antitumor activities and the possible underlying molecular mechanisms and reference for further development of novel drugs and dosage formulation in control of human cancers.

Application of HPLC-Q/orbitrap MS in the detection and identification of anticancer constituents in ethyl acetate components from Hedyotis diffusa

A feasible analytical method based on high performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (HPLC-Q/orbitrap MS) has been established for the identification and characterization of anticancer constituents in ethyl acetate components from Hedyotis diffusa in our work. The mass spectrometer provided significant fragment information both in the full MS scan and data-dependent MS² modes. Sixty-two possible compounds were analyzed and identified from the above results. Of the above 62 compounds, 12 have good separation in the positive ion mode, and 27 compounds have good separation in the anion mode. Currently, 39 have been reported in the literature related to the chemical composition of the plant, while the other 23 of the 62 compounds have not been reported. Fifteen tentatively identified compounds were given detailed descriptions. Four representative compounds from the ethyl acetate extract among the fifteen were actually isolated in good yield with silica gel column chromatography. Meanwhile, their structures were unambiguously identified as scopoletin, vanillic acid, p-coumaric acid and E-6-O-p-coumaroyl scandoside methyl ester using ¹H NMR, ¹³C NMR, IR and UV spectroscopy. The purity of the ethyl acetate extracts, the total flavonoids, from Hedyotis diffusa could reach 65.6%. The inhibitory effect on HepG-2 cells of the total flavonoids was up to 66.2 ± 2.7%. Amentoflavone, quercetin, naringenin, and rutin were selected from the total flavonoids. The amentoflavone and quercetin had better hepatoprotective activity. The inhibition rates of 500 μmol L^-1 amentoflavone and quercetin on HepG-2 cells could reach 56.2 ± 8.1% and 78.0 ± 9.3%, respectively. The EtOAc extracts could induce apoptosis in HepG2 cells by blocking the cell cycle in the G0/G1 phase. To the best of our knowledge, this is the first time that Q-orbitrap HRMS was applied to detect potential anticancer compounds in Hedyotis diffusa. This analytical method proved to be a feasible approach for the rapid detection of the potential anticancer compounds from Hedyotis diffusa.