Inhibition of early and late phase allergic reactions by Euphorbia hirta L

Traditonal Uses, Pharmacological, and Phytochemical Studies of Euphorbia: a Review

ETHNOPHARMACOLOGICAL RELEVANCE

Plants of the genus Euphorbia have long been used as traditional medicine in China, Europe, America, Turkey, India, Africa, Iran, and Pakistan for their great medicinal value and health benefits. Their stems, leaves, roots, latex are widely used to treat respiratory infections, body and skin irritations, digestive disorders, inflammatory infections, body pain, snake or scorpion bites, pregnancy, sensory disturbances, microbial and anti-cancer diseases.

OBJECTIVE

This review aimed to provide updated information on the genus Euphorbia, including traditional medicinal uses, valuation and exploitation of medicinal plants, phytochemistry, botanical characterization, pharmacological and toxicological research focused on the medicinal properties of several Euphorbias in particular their antibacterial, anti-tumor, and cell manifestations, in addition to the effect of each isolated bioactive molecule from these species and their pharmacological use including preclinical evaluation of new drugs.

MATERIALS AND METHODS

This work was conducted using scientific databases such as: PubMed, Google scholar, Scopus, Science Direct, etc. In addition, ChemDraw software has been used for the drawing of chemical molecules. The correct names of the plants were confirmed from plantlist.org. The results of this review research were interpreted, analyzed and documented based on the bibliographical information obtained.

RESULTS

Among all the species of the Euphorbiaceae family, 15 species have been demonstrated to exhibit anticancer activity, 21 species have antibacterial activity and 10 species have cytotoxic activity. The majority of the chemical constituents of this plant include triterpenoid glycosides, diterpenoids, flavonoids, and the 4α-methyl steroids. Among them, the main bioactive constituents are present in the diterpenoid fraction. The study of more than 33 steroid plants identified more than 104 compounds. Pharmacological research proved that the crude extracts and some pure compounds obtained from Euphorbia had activities for the treatment of different diseases. The objective of the present study was focused on cytotoxic, antibacterial and antitumor diseases. The study of the phytochemistry of the Euphorbia families led to the conclusion that all the plants studied had active compounds, of which 27 plants characterized by their cytotoxic effects, 7 had antibacterial effects and 10 plants had anti-tumor activities. Therefore, the safety of Euphorbia herbal medicine should be considered a top priority in the early stages of development and clinical trials.

CONCLUSIONS

Many previous studies have validated many traditional uses of Euphorbia species. The latex of some Euphorbia species seems to be toxic however studies dealing with safety and quality of these species are still incomplete. Extensive studies are needed on the Euphorbia plants before it can be fully used in clinics as a potent drug candidate, as researchers are focusing mainly on diterpenoids and triterpenoids, while there are many other types of compounds that may possess new biological activities.

A Brief Overview of Potential Treatments for Viral Diseases Using Natural Plant Compounds: The Case of SARS-Cov

The COVID-19 pandemic, as well as the more general global increase in viral diseases, has led researchers to look to the plant kingdom as a potential source for antiviral compounds. Since ancient times, herbal medicines have been extensively applied in the treatment and prevention of various infectious diseases in different traditional systems. The purpose of this review is to highlight the potential antiviral activity of plant compounds as effective and reliable agents against viral infections, especially by viruses from the coronavirus group. Various antiviral mechanisms shown by crude plant extracts and plant-derived bioactive compounds are discussed. The understanding of the action mechanisms of complex plant extract and isolated plant-derived compounds will help pave the way towards the combat of this life-threatening disease. Further, molecular docking studies, in silico analyses of extracted compounds, and future prospects are included. The in vitro production of antiviral chemical compounds from plants using molecular pharming is also considered. Notably, hairy root cultures represent a promising and sustainable way to obtain a range of biologically active compounds that may be applied in the development of novel antiviral agents.

Optimization of Extraction Conditions of Phytochemical Compounds and Anti-Gout Activity of Euphorbia hirta L. (Ara Tanah) Using Response Surface Methodology and Liquid Chromatography-Mass Spectrometry (LC-MS) Analysis

Gout is a common disease affected most of the people due to the elevation of uric acid in the blood. Flavonoid and phenolic compounds are reported to exert the anti-gout activity of medicinal plants. Hence, this study aimed at optimizing the extraction conditions of phenolic and flavonoid compounds as well as the anti-gout (xanthine oxidase inhibitory activity) in vitro of Euphorbia hirta using response surface methodology (RSM). The plant part used was the whole plant excluding roots. The effects of three independent variables (extraction time, X ₁; extraction temperature, X ₂; and solid-to-liquid ratio, X ₃) on three response variables (total flavonoid content, Y ₁; total phenolic content, Y ₂; and xanthine oxidase inhibitory activity, Y ₃) were determined using central composite design (CCD) while phytochemical profiling of the extracts was determined by liquid chromatography-mass spectrometry (LC-MS). Quadratic models produced a satisfactory fitting of the experimental data with regard to total flavonoid content (r ² = 0.9407, p < 0.0001), total phenolic content (r ² = 0.9383, p < 0.0001), and xanthine oxidase inhibitory activity (r ² = 0.9794, p < 0.0001). The best extraction conditions observed for total flavonoid content, total phenolic content, and xanthine oxidase inhibitory activity were at a temperature of 79.07°C for 17.42 min with solid-to-liquid ratio of 1 : 20 g/ml. The optimum values for total flavonoid, total phenolic, and xanthine oxidase inhibitory activity were 67.56 mg RE/g, 155.21 mg GAE/g, and 91.42%, respectively. The main phytochemical compounds in the optimized E. hirta extract are neochlorogenic acid, quercetin-3β-D-glucoside, syringic acid, caffeic acid, ellagic acid, astragalin, afzelin, and quercetin. As conclusion, this study clearly demonstrated the best conditions to obtain higher xanthine oxidase inhibitory activity and phytochemical compounds which can be further used for the development of anti-gout agents.

Reduction of adhesion molecule production and alteration of eNOS and endothelin-1 mRNA expression in endothelium by Euphorbia hirta L. through its beneficial β-amyrin molecule

The inflammatory reaction in large blood vessels involves up-regulation of vascular adhesion molecules such as endothelial cell selectin (E-selectin), soluble vascular cell adhesion molecule (sVCAM)-1, and soluble intercellular adhesion molecule (sICAM)-1. These vascular dysfunctions are associated with the development of atherosclerosis. β-Amyrin, an active component of Euphorbia hirta L., has potent anti-inflammatory effects. So far, its preventive effects against the expression of inflammatory mediator-induced adhesion molecules have not been investigated. Endothelial cells (SVEC4-10 cell line) were treated with 50% RAW conditioned media (i.e., normal SVEC4-10 culture media contains 50% of lipopolysaccharide-activated macrophage culture media) without or with β-amyrin (0.6 and 0.3 µM). The production levels of E-selectin, sICAM-1, and sVCAM-1 in the SVEC4-10 cells were measured with ELISA assay kits. Under the same treatment conditions, expression of endothelin (ET)-1 and endothelial type of NO synthase (eNOS) mRNA were analyzed by RT-PCR and agarose gel. With β-amyrin, the 50% RAW conditioned media-induced E-selectin, sICAM-1, and sVCAM-1 levels as well as ET-1 gene expression were all suppressed. β-Amyrin treatment also restored the 50% RAW conditioned media-suppressed eNOS mRNA expression. These data indicate that β-amyrin is potentially useful in preventing chronic inflammation-related vascular diseases.

Chemical analysis, inhibition of biofilm formation and biofilm eradication potential of Euphorbia hirta L. against clinical isolates and standard strains

Background

The frequent occurrences of antibiotic-resistant biofilm forming pathogens have become global issue since various measures that had been taken to curb the situation led to failure. Euphorbia hirta, is a well-known ethnomedicinal plant of Malaysia with diverse biological activities. This plant has been used widely in traditional medicine for the treatment of gastrointestinal, bronchial and respiratory ailments caused by infectious agents.

Methods

In the present study, chemical compositions of methanol extract of E. hirta L. aerial part was analyzed by gas chromatography and gas chromatography coupled to mass spectrometry. A relevant in vitro model was developed to assess the potency of the E. hirta extract to inhibit the bacterial biofilm formation as well as to eradicate the established biofilms. Besides biofilm, E. hirta extract was also evaluated for the inhibition efficacy on planktonic cells using tetrazolium microplate assay. For these purposes, a panel of clinically resistant pathogens and American type culture collection (ATCC) strains were used.

Results

The methanolic extract of aerial part of E. hirta was predominantly composed of terpenoid (60.5%) which is often regarded as an active entity accountable for the membrane destruction and biofilm cell detachment. The highest antibacterial effect of crude E. hirta extract was observed in the clinical isolates of Pseudomonas aeruginosa with minimum inhibitory concentration (MIC) value of 0.062 mg/ml. The extract also displayed potent biofilm inhibition and eradication activity against P. aeruginosa with minimum biofilm inhibition concentration (MBIC) and minimum biofilm eradication concentration (MBEC) values of 0.25 mg/ml and 0.5 mg/ml, respectively.

Conclusions

The crude methanol extract of E. hirta has proven to have interesting and potential anti-biofilm properties. The findings from this study will also help to establish a very promising anti-infective phytotherapeutical to be exploited in the pharmaceutical industries.

Antiradical and Cytotoxic Activities of Varying Polarity Extracts of the Aerial Part ofEuphorbia hirtaL

Euphorbia hirtais a well-known ethnomedicinal plant with diverse biological activities. The aim of the present study is to investigate the antiradical activities of various solvent extracts of the aerial part ofE. hirtaas well as to determine the possible cytotoxicity of these extracts. The aerial part ofE. hirtawas extracted with different solvent systems in order to increase polarity. The solvents used were hexane, dichloromethane (DCM), ethyl acetate (EA), ethanol (EtOH), and methanol (MeOH). The contents of total phenols and total flavonoids were analyzed by UV spectrophotometry, whereas the potential free radical-scavenging activities of the extracts were evaluated using the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), theβ-carotene-linoleic acid bleaching system, and reducing power. The EtOH extract exhibited the highest total phenolic content (237.9±2.26 mg GAE/g), and DCM extract scored the highest total flavonoid content (121±0.15 mg CE/g). The MeOH extract showed a potent free radical-scavenging activity as evidenced by low EC50at 42.81 µg/mL. Interestingly, the EtOH extract demonstrated the highest reducing power activity with EC50value of 6.18 µg/mL. Inβ-carotene-linoleic acid assay, oxidation of linoleic acid was effectively inhibited by DCM extract with96.15±0.78%. All the extracts showed no cytotoxic activity against Vero cells.

A molecular pharmacology study into the anti-inflammatory actions of Euphorbia hirta L. on the LPS-induced RAW 264.7 cells through selective iNOS protein inhibition

Euphorbia hirta L. has been widely used in India and Chinese society. The molecular pharmacology basis of its anti-inflammatory effect is revealed in this work. The ethanol extract of Euphorbia hirta L. (Eh) and its active component were studied in lipopolysaccharide (LPS)-activated macrophage cells (RAW 264.7) as an established inflammation model. After activation, nitric oxide (NO) production and expression of iNOS protein and iNOS mRNA were measured by using a colorimetric assay (Griess reagent), western blotting, and reverse transcription polymerase chain reaction (RT-PCR), respectively. The alteration in the content of PGE(2), TNFalpha, and IL-6 was concurrently monitored by ELISA. In results, we found that in the concentration range without showing cytotoxicity, Eh produced a remarkable anti-inflammatory effect via its active component of beta-amyrin and showed a dose-related inhibition of LPS-induced NO production. This phenomenon is in accordance with a substantial inhibition of iNOS protein. However, the expression of iNOS gene was unaffected by Eh treatments. Compared with indomethacin, Eh has much more potency and a specific action of NO inhibition but Eh works less specifically on PGE(2), IL-6, and TNF-alpha inhibition. The extract of Euphorbia hirta L. and its component beta-amyrin are able to block most of the iNOS protein functions and NO induction, and could therefore be new selective NO inhibitors with great potential in treating arthritis inflammation.

Anti-allergic effects of herbal product from Allium cepa (bulb)

Allium cepa (Family Liliaceae) is a reputed Indian medicinal herb that is prescribed as an effective remedy for several ailments in the Ayurvedic system of medicine. The aim of this study was to evaluate its efficacy against various events responsible for Type I allergic reactions. A herbal fraction (ALC-02) from A. cepa (bulb) inhibited histamine release and attenuated intracellular calcium levels in Compound 48/80-induced rat peritoneal mast cells. It also prevented Compound 48/80-mediated systemic anaphylaxis while lowering histamine levels in plasma. ALC-02 suppressed carrageenan-induced rat paw edema. It inhibited eosinophil peroxidase activity and protein content in bronchoalveolar lavage fluid (BALF) of ovalbumin-challenged mice. In this experiment ALC-02 also caused a substantial reduction in lipid peroxidation in BALF/lung tissue and augmented superoxide dismutase activity in lung tissue. ALC-02 suppressed erythrocytic lysis caused by Triton X-100. A significant quenching of 1,1-diphenyl-2-picrylhydrazyl radical by ALC-02 was observed. The results have shown a promising anti-allergic profile of ALC-02 that could be attributed to its potential antihistaminic, anti-inflammatory, and antioxidant activities.

Anti-anaphylactic effect of Euphorbia hirta

The Euphorbia hirta ethanolic extract (EH A001) was found to possess a prominent anti-anaphylactic activity. A preventive effect of EH-A001 given by oral route at dose from 100 to 1000 mg/kg was observed against compound 48/80-induced systemic anaphylaxis. At the same range of dose, EH-A001 inhibited passive cutaneous anaphylaxis (PCA) in rat and active paw anaphylaxis in mice. A suppressive effect of EH-A001 was observed on the release of TNF-alpha and IL-6 from anti-DNP-HSA activated rat peritoneal mast cells.