Portulaca oleracea L. polysaccharides enhance the immune efficacy of dendritic cell vaccine for breast cancer

Nano-formulated delivery of active ingredients from traditional Chinese herbal medicines for cancer immunotherapy

Cancer immunotherapy has garnered promise in tumor progression, invasion, and metastasis through establishing durable and memorable immunological activity. However, low response rates, adverse side effects, and high costs compromise the additional benefits for patients treated with current chemical and biological agents. Chinese herbal medicines (CHMs) are a potential treasure trove of natural medicines and are gaining momentum in cancer immunomodulation with multi-component, multi-target, and multi-pathway characteristics. The active ingredient extracted from CHMs benefit generalized patients through modulating immune response mechanisms. Additionally, the introduction of nanotechnology has greatly improved the pharmacological qualities of active ingredients through increasing the hydrophilicity, stability, permeability, and targeting characteristics, further enhancing anti-cancer immunity. In this review, we summarize the mechanism of active ingredients for cancer immunomodulation, highlight nano-formulated deliveries of active ingredients for cancer immunotherapy, and provide insights into the future applications in the emerging field of nano-formulated active ingredients of CHMs.

Two novel ketone alkaloids from Portulaca oleraceaL. and their anti-inflammatory activities

Eleven compounds were obtained from Portulaca oleracea L., including two novel ketone alkaloids, (1, 2), 4-hydroxy-3-methoxybenzamide (3) (isolated for the first time), β-adenosine (4), oleracrylimide A and B (5, 6), oleracein H, C, D, Q and A (7-11). The two novel ketone alkaloids were identified as 5-acetyl-5-methylcyclopent-2-ene-1-carboxamide (1), named oleraciamide H, and (2 R,3S,4R,5R)-5-((R)-1,2-dihydroxyethyl)-3,4-dihydroxytetrahydrofuran-2-yl glycinate (2), named oleracone Q by spectroscopic methods, including 1D, 2D NMR and compound fingerprints. Additionally, their anti-inflammatory activities were tested via RAW 264.7 cells induced by LPS and found that they could significantly inhibit the release of IL-1β and TNF-α.

A review on ethnopharmacology, phytochemistry, pharmacology and potential uses of Portulaca oleracea L

ETHNOPHARMACOLOGICAL RELEVANCE

Portulaca oleracea L. (PO), popularly known as purslane, has been documented in ethnopharmacology in various countries and regions. Traditional application records indicated that PO might be used extensively to treat the common cold, dysentery, urinary tract infections, coughing, eye infections, skin problems, gynecological diseases, and pediatric illnesses.

AIM OF THE REVIEW

This paper includes a systematic review of the traditional usage, phytochemicals, pharmacological activity, and potential uses of PO to provide an overview of the research for further exploitation of PO resources.

MATERIALS AND METHODS

This article uses "Portulaca oleracea L." and "purslane" as the keywords and collects relevant information on PO from different databases, including PubMed, Web of Science, Springer, Science Direct, ACS, Wiley, CNKI, Baidu Scholar, Google Scholar, and ancient meteria medica.

RESULTS

PO is a member of the Portulacaceae family and is grown worldwide. Traditional Chinese medicine believes that purslane has the effect of improving eyesight, eliminating evil qi, quenching thirst, purgation, diuresis, hemostasis, regulating qi, promoting hair growth, detoxifying, and avoiding epidemic qi. Recent phytochemical investigations have shown that PO is a rich source of flavonoids, homoisoflavonoids, alkaloids, organic acids, esters, lignans, terpenoids, catecholamines, sterols, and cerebrosides. The purslane extracts or compounds have exhibited numerous biological activities such as anti-inflammatory, immunomodulatory, antimicrobial, antiviral, antioxidant, anticancer, renoprotective, hepatoprotective, gastroprotective, metabolic, muscle relaxant, anti-asthmatic and anti-osteoporosis properties. The significant omega-3 fatty acids, vital amino acids, minerals, and vitamins found in purslane also provide nutritional benefits. Purslane as a food/feed additive in the food industry and animal husbandry has caused concern. Its global wide distribution and tolerance to abiotic stress characteristics make it in the future sustainable development of agriculture a certain position.

CONCLUSIONS

Based on traditional usage, phytochemicals, and pharmacological activity, PO is a potential medicinal and edible plant with diverse pharmacological effects. Due to purslane's various advantages, it may have vast application potential in the food and pharmaceutical industries and animal husbandry.

Research Progress on the Anticancer Activity of Plant Polysaccharides

Tumor is a serious threat to human health, with extremely high morbidity and mortality rates. However, tumor treatment is challenging, and the development of antitumor drugs has always been a significant research focus. Plant polysaccharides are known to possess various biological activities. They have many pharmacological properties such as immunomodulation, antitumor, antiviral, antioxidative, antithrombotic, and antiradiation effects, reduction of blood pressure and blood sugar levels, and protection from liver injury. Among these effects, the antitumor effect of plant polysaccharides has been widely studied. Plant polysaccharides can inhibit tumor proliferation and growth by inhibiting tumor cell invasion and metastasis, inducing cell apoptosis, affecting the cell cycle, and regulating the tumor microenvironment. They also have the characteristics of safety, high efficiency, and low toxicity, which can alleviate, to a certain extent, the adverse reactions caused by traditional tumor treatment methods such as surgery, radiotherapy, and chemotherapy. Therefore, this paper systematically summarizes the direct antitumor effects of plant polysaccharides, their regulatory effects on the tumor microenvironment, and intervening many common high-incidence tumors in other ways. It also provides data support for the administration of plant polysaccharides in modern tumor drug therapy, enabling the identification of new targets and development of new drugs for tumor therapy.

Antibacterial diarrhea effect and action mechanism of Portulaca oleracea L. water extract based on the regulation of gut microbiota and fecal metabolism

BACKGROUND

Portulaca oleracea has served as food and folk medicine in many parts of the world for thousands of years. Portulaca oleracea extract (POE) was prepared from fresh plants. This study aims to evaluate the antibacterial diarrhea effect and explore the possible mechanism.

RESULTS

POE was effective in reducing diarrhea rate, improving intestinal tissue, and reducing cytokines concentrations of interleukin (IL)-6, IL-10, IL-12 p40 and TNF-α in blood. Besides, the result of histological observation showed that the mucus layer thickness and crypt length in the POE-treated group was higher than that in the model group. The POE could significantly upregulate the protein expression of MUC2, occludin and ZO-1. 16S rRNA sequencing analysis showed that Parabacteroides, Clostridium and Muribaculaceae may be the key functional microflora of POE. The non-targeted metabolomics also suggested that the antibacterial diarrheal effects of P. oleracea may be attributed to the regulation of amino acid metabolism and composition of the gut microbiota.

CONCLUSION

Portulaca oleracea has definite clinical efficacy against bacterial diarrhea and anti-inflammatory effects. Its regulation of gut microbiota and fecal metabolism may account for its antibacterial diarrhea and anti-inflammatory effects. © 2023 Society of Chemical Industry.

Natural polysaccharides exert anti-tumor effects as dendritic cell immune enhancers

With the development of immunotherapy, the process of tumor treatment is also moving forward. Polysaccharides are biological response modifiers widely found in plants, animals, fungi, and algae and are mainly composed of monosaccharides covalently linked by glycosidic bonds. For a long time, polysaccharides have been widely used clinically to enhance the body's immunity. However, their mechanisms of action in tumor immunotherapy have not been thoroughly explored. Dendritic cells (DCs) are a heterogeneous population of antigen presenting cells (APCs) that play a crucial role in the regulation and maintenance of the immune response. There is growing evidence that polysaccharides can enhance the essential functions of DCs to intervene the immune response. This paper describes the research progress on the anti-tumor immune effects of natural polysaccharides on DCs. These studies show that polysaccharides can act on pattern recognition receptors (PRRs) on the surface of DCs and activate phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT), mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB), Dectin-1/Syk, and other signalling pathways, thereby promoting the main functions of DCs such as maturation, metabolism, antigen uptake and presentation, and activation of T cells, and then play an anti-tumor role. In addition, the application of polysaccharides as adjuvants for DC vaccines, in combination with adoptive immunotherapy and immune checkpoint inhibitors (ICIs), as well as their co-assembly with nanoparticles (NPs) into nano drug delivery systems is also introduced. These results reveal the biological effects of polysaccharides, provide a new perspective for the anti-tumor immunopharmacological research of natural polysaccharides, and provide helpful information for guiding polysaccharides as complementary medicines in cancer immunotherapy.

Phytochemical Characteristics and Anti-Inflammatory, Immunoregulatory, and Antioxidant Effects of Portulaca oleracea L.: A Comprehensive Review

Portulaca oleracea L. (P. oleracea) or purslane is a plant from the Portulacaceae family, which is used as food and traditional medicine for various diseases. This review article provides comprehensive information on the antioxidant, immunomodulatory, and anti-inflammatory properties of P. oleracea and its constituents. The literature survey of the different databases until the end of June 2023 was explored based on the keywords including the "P. oleracea, purslane, anti-inflammatory, immunomodulatory, and antioxidant properties." The plant contains flavonoids, alkaloids, terpenoids, fatty acids, vitamins, minerals, and some other compounds. The results indicated that P. oleracea and its constituents showed anti-inflammatory and immunomodulatory properties through reduction of inflammatory mediators including interferon gama (IFN-γ), interleukin (IL)-10, IL-4, tumor necrosis factor-alpha (TNF-α), and nitric oxide. Improvement in cytokines' serum levels (IFN-γ, IL-10, and IL-4) and increased IgG and IgM serum levels, as well as reduction of IgE, phospholipase A2, and total protein were demonstrated for P. oleracea. The plant and its constituents also improved oxidative stress by reduction of oxidant and increase of antioxidant markers. P. oleracea could be considered as an effective remedy for various inflammatory and immune diseases.

Portulaca oleracea L. Polysaccharide Inhibits Porcine Rotavirus In Vitro

Diarrhea is one of the most common causes of death in young piglets. Porcine rotavirus (PoRV) belongs to the genus Rotavirus within the family Reoviridae, and is considered to be the primary pathogen causing diarrhea in piglets. Portulaca oleracea L. (POL) has been reported to alleviate diarrhea and viral infections. However, the antiviral effect of Portulaca oleracea L. polysaccharide (POL-P), an active component of POL, on PoRV infection remains unclear. This study demonstrated that the safe concentration range of POL-P in IPEC-J2 cells is 0-400 μg/mL. POL-P (400 μg/mL) effectively inhibits PoRV infection in IPEC-J2 cells, reducing the expression of rotavirus VP6 protein, mRNA and virus titer. Furthermore, on the basis of viral life cycle analysis, we showed that POL-P can decrease the expression of PoRV VP6 protein, mRNA, and virus titer during the internalization and replication stages of PoRV. POL-P exerts antiviral effects by increasing IFN-α expression and decreasing the expression levels of TNF-α, IL-6, and IL-10 inflammatory factors. Overall, our study found that POL-P is a promising candidate for anti-PoRV drugs.

Extraction, Purification, Structural Characteristics, Biological Activity and Application of Polysaccharides from Portulaca oleracea L. (Purslane): A Review

Portulaca oleracea L. (purslane) is a widely distributed plant with a long history of cultivation and consumption. Notably, polysaccharides obtained from purslane exhibit surprising and satisfactory biological activities, which explain the various benefits of purslane on human health, including anti-inflammatory, antidiabetic, antitumor, antifatigue, antiviral and immunomodulatory effects. This article systematically reviews the extraction and purification methods, chemical structure, chemical modification, biological activity and other aspects of polysaccharides from purslane collected in the Chinese Pharmacopoeia, Flora of China, Web of Science, PubMed, Baidu Scholar, Google Scholar and CNKI databases in the last 14 years, using the keywords "Portulaca oleracea L. polysaccharides" and "purslane polysaccharides". The application of purslane polysaccharides in different fields is also summarized, and its application prospects are also discussed. This paper provides an updated and deeper understanding of purslane polysaccharides, which will provide useful guidance for the further optimization of polysaccharide structures and the development of purslane polysaccharides as a novel functional material, as well as a theoretical basis for its further research and application in human health and manufacturing development.

Network pharmacology and molecular docking analysis on the mechanism of Cordyceps militaris polysaccharide regulating immunity through TLR4/TNF-α pathwayss

The role of polysaccharide components in the immune system, especially immunomodulatory effects, has received increasing attention. In this context, in this study, network pharmacology was adopted to explore the hypothesis of a multitarget mechanism for immune modulation by Chrysalis polysaccharides. A total of 174 common targets were screened by network pharmacology, with the main ones being TNF, MAPK3, CASP3, VEGFA, and STAT3, mostly enriched in the Toll pathway. The molecular docking results showed that the polysaccharide fraction of Chrysalis binds well to TNF proteins. Besides, in vitro cellular assays were performed to verify the ability of Chrysalis polysaccharides to regulate macrophage polarization and to screen for macrophage surface receptors. Furthermore, in vivo experiments were conducted to prove the activation of TLR4 and TNF-α protein expression in mice by Chrysalis polysaccharide.

Effects of dietary polyherbal mixtures on growth performance, antioxidant capacity, immune function and jejunal health of yellow-feathered broilers

This study aimed to investigate the effects of polyherbal mixtures (PHM) on growth performance, antioxidant capacities, immune function, and intestinal health in yellow-feathered broilers. PHM is composed of five traditional Chinese medicine herbs (Portulaca oleracea L., Radix Sophora flavescens, Thalictrum glandulosissimum, Terra flava usta, and Pogostemon cablin). A total of 270 one-day-old yellow-feathered broilers were randomly allotted into 3 treatments for a 42-d feeding trial, each with 6 replicates of 15 birds. The dietary treatments consisted of a basal diet (CON), a basal diet supplemented with 50 mg/kg chlortetracycline (CTC), and a basal diet supplemented with 1000 mg/kg PHM. The results showed that dietary PHM supplementation increased body weight, ADG, and decreased F/G compared to the CON. PHM also increased spleen index and mRNA expression of IL-4 (d 21), and thymus index, serum IgA (d 42) and IgG, IL-4 and sIgA in jejunal mucosa (d 21 and 42), but decreased serum IFN-γ and mRNA expression of IFN-γ (d 21 and 42). In addition, PHM increased serum SOD, GSH-Px (d 21 and 42) and T-AOC (d 42), but decreased the content of serum MDA (d 21), the up-regulated mRNA expression of GSH-Px, CAT (d 21), SOD and CAT (d 42). Furthermore, PHM also improved the intestinal epithelial barrier indicators by the up-regulated mRNA expression of CLDN-1, OCLN (d 21 and 42) and ZO-1 (d 21), and the increased of villus height and villus height to crypt depth in jejunum (d 42). The high-throughput sequencing results showed that dietary PHM supplementation increased the alpha diversity and relative abundance of Oscillospira and Ruminococcus (d 21) and Lactobacillus (d 42), whereas decreasing that of Enterococcus (d 21) compared with CON. PICRUSt analysis revealed that metabolic pathways of carbohydrate, energy, lipid, cofactors, and vitamins were significantly enriched in the PHM group. Spearman's correlation analysis revealed that the genera Lactobacillus, Enterococcus, Ruminococcus, Oscillospira, and Faecalibacterium were related to growth performance, intestinal integrity, immune-related factors, antioxidant indices, and tight junction proteins. In conclusion, the results indicated that dietary PHM supplementation improved growth performance and immune status of yellow-feathered broilers by enhancing antioxidant capacities, barrier function, and modulated jejunal microbial communities. PHM used in our study has the potential to replace prophylactic antibiotic use in poultry production systems.

The use of African medicinal plants in cancer management

Cancer is the third leading cause of premature death in sub-Saharan Africa. Cervical cancer has the highest number of incidences in sub-Saharan Africa due to high HIV prevalence (70% of global cases) in African countries which is linked to increasing the risk of developing cervical cancer, and the continuous high risk of being infected with Human papillomavirus In 2020, the risk of dying from cancer amongst women was higher in Eastern Africa (11%) than it was in Northern America (7.4%). Plants continue to provide unlimited pharmacological bioactive compounds that are used to manage various illnesses, including cancer. By reviewing the literature, we provide an inventory of African plants with reported anticancer activity and evidence supporting their use in cancer management. In this review, we report 23 plants that have been used for cancer management in Africa, where the anticancer extracts are usually prepared from barks, fruits, leaves, roots, and stems of these plants. Extensive information is reported about the bioactive compounds present in these plants as well as their potential activities against various forms of cancer. However, information on the anticancer properties of other African medicinal plants is insufficient. Therefore, there is a need to isolate and evaluate the anticancer potential of bioactive compounds from other African medicinal plants. Further studies on these plants will allow the elucidation of their anticancer mechanisms of action and allow the identification of phytochemicals that are responsible for their anticancer properties. Overall, this review provides consolidated and extensive information not only on diverse medicinal plants of Africa but on the different types of cancer that these plants are used to manage and the diverse mechanisms and pathways that are involved during cancer alleviation.

Suppressive effects of bioactive herbal polysaccharides against different cancers: From mechanisms to translational advancements

BACKGROUND

Fueled by rapidly evolving comprehension of multifaceted nature of cancers, recently emerging preclinical and clinical data have supported researchers in the resolution of knowledge gaps to deepen the understanding of the molecular mechanisms. The extra-ordinary and bewildering chemical diversity encompassed by biologically active natural products continues to be of relevance to drug discovery. Accumulating evidence has spurred a remarkable evolution of concepts related to pharmacological target of oncogenic signaling pathways by polysaccharides in different cancers.

PURPOSE

The objective of the current review is to provide new insights into study progress on anticancer effects of bioactive herbal polysaccharides.

METHODS

PubMed, Scopus, Web of Science, Embase, and other databases were searched for articles related to anticancer effects of polysaccharides. Searches were conducted to locate relevant publications published up to October 2022.

RESULTS

Polysaccharides have been reported to pleiotropically modulate TGF/SMAD, BMP/SMAD, TLR4, mTOR, CXCR4 and VEGF/VEGFR cascades. We have also summarized how different polysaccharides regulated apoptosis and non-coding RNAs. Additionally, this mini-review describes increasingly sophisticated understanding related to polysaccharides mediated tumor suppressive and anti-metastatic effects in tumor-bearing mice. We have also provided an overview of the clinical trials related to chemopreventive role of polysaccharides.

CONCLUSION

Genomic and proteomic findings from these studies will facilitate 'next-generation' clinical initiatives in the prevention/inhibition of cancer.

An Overview of Antitumour Activity of Polysaccharides

Cancer incidence and mortality are rapidly increasing worldwide; therefore, effective therapies are required in the current scenario of increasing cancer cases. Polysaccharides are a family of natural polymers that hold unique physicochemical and biological properties, and they have become the focus of current antitumour drug research owing to their significant antitumour effects. In addition to the direct antitumour activity of some natural polysaccharides, their structures offer versatility in synthesizing multifunctional nanocomposites, which could be chemically modified to achieve high stability and bioavailability for delivering therapeutics into tumor tissues. This review aims to highlight recent advances in natural polysaccharides and polysaccharide-based nanomedicines for cancer therapy.

UHPLC-Orbitrap-MS Tentative Identification of 51 Oleraceins (Cyclo-Dopa Amides) in Portulaca oleracea L. Cluster Analysis and MS2 Filtering by Mass Difference

Oleraceins are a class of indoline amide glycosides found in Portulaca oleracea L. (Portulacaceae), or purslane. These compounds are characterized by 5,6-dihydroxyindoline-2-carboxylic acid N-acylated with cinnamic acid derivatives, and many are glucosylated. Herein, hydromethanolic extracts of the aerial parts of purslane were subjected to UHPLC-Orbitrap-MS analysis, in negative ionization mode. Diagnostic ion filtering (DIF), followed by diagnostic difference filtering (DDF), were utilized to automatically filter out MS data and select plausible oleracein structures. After an in-depth MS² analysis, a total of 51 oleracein compounds were tentatively identified. Of them, 26 had structures, matching one of the already known oleracein, and the other 25 were new, undescribed in the literature compounds, belonging to the oleracein class. Moreover, based on selected diagnostic fragment ions, clustering algorithms and visualizations were utilized. As we demonstrate, clustering methods provide valuable insights into the mass fragmentation elucidation of natural compounds in complex mixtures.