The therapeutic effects of Portulaca oleracea L. in hepatogastric disorders

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.

Two new natural products from Portulaca oleracea L. and their bioactivities

Two new natural products, belonging to alkaloids, identified as ((2R,3S,4R,5R)-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-3,4-dihydroxytetrahydrofuran-2-yl)methyl acetate (1) and (5-hydroxypyridin-2-yl)methyl acetate (2), were isolated from Portulaca oleracea L. The structures were identified by spectroscopic methods, including 1D, 2D NMR, and UHPLC-ESI-QTOF/MS methods. Meanwhile, the anti-inflammatory and anticholinesterase bioactivities were found in these two compounds.

Portulaca oleracea L. organic acid extract inhibits persistent methicillin-resistant Staphylococcus aureus in vitro and in vivo

Staphylococcus aureus continues to be one of the most important pathogens capable of causing a wide range of infections in different sites of the body in humans and livestock. With the emergence of methicillin-resistant strains and the introduction of strict laws on antibiotic usage in animals, antibiotic replacement therapy has become increasingly popular. Previous studies have shown that Portulaca oleracea L. extract exerts a certain degree of bacteriostatic effect, although the active ingredients are unknown. In the present study, the antibacterial activity of the organic acid of P. oleracea (OAPO) against S. aureus was examined using a series of experiments, including the minimum inhibitory concentration, growth curve, and bacteriostasis curve. In vitro antibacterial mechanisms were evaluated based on the integrity and permeability of the cell wall and membrane, scanning electron microscopy, and soluble protein content. A mouse skin wound recovery model was used to verify the antibacterial effects of OAPO on S. aureus in vivo. The results showed that OAPO not only improved skin wound recovery but also decreased the bacterial load in skin wounds. Moreover, the number of inflammatory cells and cytokines decreased in the OAPO-treated groups. In summary, this study reports a botanical extract that can inhibit S. aureus in vitro and in vivo, indicating the potential use of OAPO to prevent and control S. aureus infection in the near future.

Protective Effect of Portulaca oleracea Extract Against Lipopolysaccharide-Induced Neuroinflammation, Memory Decline, and Oxidative Stress in Mice: Potential Role of miR-146a and miR-let 7

Neuroinflammation is an adaptive immune response to the central nervous system (CNS) injury induced by infection or toxins. MicroRNAs (miRs) showed critical roles in neuroinflammation as either proinflammatory or anti-inflammatory molecules. Interestingly, Portulaca oleracea (purslane) is an edible plant capable of ameliorating several diseases, including headache, burns, and diabetes; however, its effect on the neuroinflammation-associated miRs was not previously investigated. This study aimed to investigate the effect of aqueous purslane extract on the neuroinflammation induced by lipopolysaccharide (LPS) in mice and to identify its effect on animal cognition, oxidative stress, and expressions of miR-146a and miR-let 7. Adult mice were divided into the following groups: Normal group, LPS group, and Purslane+LPS group. Novel target recognition test, brain histopathology, and measurement of oxidative stress and inflammatory markers were performed. The results showed that LPS group exhibited significant decline in the cognitive memory, brain histopathological injury and a decrease in the number of intact neurons compared to the normal group. Furthermore, the LPS group showed a significant increase in malondialdehyde concentration, whereas superoxide dismutase and catalase activities were decreased. The LPS group also showed an increase in the inflammatory markers tumor necrosis factor-α and nuclear factor kappa B and downregulation of miR-146a and miR-let 7 expressions in the brain cells compared to the normal group, P value <.05. Interestingly, all these changes were reversed by administration of the aqueous purslane extract. In conclusion, the aqueous purslane extract protected from LPS-induced neuroinflammation and memory decline in mice through antioxidant and anti-inflammatory effect where upregulation of miR-146a and miR-1et 7 expressions was involved.

A review on bioactive phytochemicals and ethnopharmacological potential of purslane (Portulaca oleracea L.)

The Portulaca oleracea L. commonly known as purslane is distributed all over the world and easily grows in diverse soil and climatic conditions. It has been traditionally used as a nutritious and ethnomedicinal food across the globe. Various studies have shown that the plant is a rich source of various important phytochemicals such as flavonoids, alkaloids, terpenoids, proteins, carbohydrates, and vitamins such as A, C, E, and B, carotenoids and minerals such as phosphorus, calcium, magnesium and zinc. It is particularly very important because of the presence of a very high concentration of omega-3- fatty acids especially α-linolenic acid, gamma-linolenic acid and linoleic acid, which are not generally synthesized in terrestrial plants. Various parts of purslane are known for ethnomedicinal and pharmacological uses because of its anti-inflammatory, antidiabetic, skeletal muscle relaxant, antitumor, hepatoprotective, anticancer, antioxidant, anti-insomnia, analgesic, gastroprotective, neuroprotective, wound healing and antiseptic activities. Due to multiple benefits of purslane, it has become an important wonder crop and various scientists across the globe have shown much interest in it as a healthy food for the future. In this review, we provide an update on the phytochemical and nutritional composition of purslane, its usage as nutritional and an ethnomedicinal plant across the world. We further provide a detailed account on ethnopharmacological studies that have proved the ethnomedicinal properties of purslane.

Three novel alkaloids from Portulaca oleracea L. and their anti-inflammatory bioactivities

Three novel alkaloids, identified as (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxyphenyl)acrylamide (1), named oleracrylimide A, (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxy-3-methoxyphenyl)acrylamide (2), named oleracrylimide B, and (E)-N-((2R)-3-(2,5-dihydroxy-4-((3,4,5-trihydroxy-6-(((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)methyl)tetrahydro-2H-pyran-2-yl)oxy)phenyl)-2-hydroxypropanoyl)-3-(4-hydroxy-3-methoxyphenyl)acrylamide (3), named oleracrylimide C were isolated from Portulaca oleracea L. and the structures of the three novel compounds were determined by 1D and 2D NMR, circular dichroism, and UHPLC-ESI-QTOF/MS spectroscopic methods. Moreover, the bioactivities of anti-inflammation of the three compounds were investigated via testing RAW 264.7 macrophage cell stimulated by Lipopolysaccharide.

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

Previous studies have reported that Portulaca oleracea L. polysaccharides (POL-P3b) is an immunoregulatory agent. However, few studies exist on POL-P3b as a novel immune adjuvant in combination with the DC vaccine for breast cancer treatment. In this work, a DC vaccine loaded with mouse 4T1 tumor cell antigen was prepared to evaluate the properties of POL-P3b in inducing the maturation and function of DC derived from mouse bone marrow, and then to investigate the effect of the DC vaccine combined with POL-P3b on breast cancer in vivo and in vitro. Morphological changes of DC were observed using scanning electron microscopy. Phenotypic and functional analyses of DC were detected by flow cytometry and allogeneic lymphocyte reaction. Cytokine levels in the DC culture supernatant were detected by ELISA. Western blotting analysis was used for the protein expression of TLR4, MyD88 and NF-κB. Apoptosis detection and protein expression of the tumor tissue were analyzed by TUNEL staining and immunohistochemistry, respectively. The security of POL-P3b was evaluated by the detection of hematological and blood biochemical indicators and pathological analysis for tissues. POL-P3b can induce DC activation and maturation, which is attributed to increasing the specific anti-tumor immune response, and the mechanism of action involved in the TLR4/MyD88/NF-κB signaling pathway. Experimental results in vivo further suggested that the administration of POL-P3b-treated antigen-primed DC achieved remarkable tumor growth inhibition through inducing apoptosis and enhancing immune responses. Moreover, the POL-P3b-treated DC vaccine was able to inhibit lung metastases. The results proved the feasibility of POL-P3b as an edible adjuvant of the DC vaccine for anti-breast cancer therapy.