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

The Phytochemistry and Pharmacology of Tulbaghia, Allium, Crinum and Cyrtanthus: ‘Talented’ Taxa from the Amaryllidaceae

Amaryllidaceae is a significant source of bioactive phytochemicals with a strong propensity to develop new drugs. The genera Allium, Tulbaghia, Cyrtanthus and Crinum biosynthesize novel alkaloids and other phytochemicals with traditional and pharmacological uses. Amaryllidaceae biomolecules exhibit multiple pharmacological activities such as antioxidant, antimicrobial, and immunomodulatory effects. Traditionally, natural products from Amaryllidaceae are utilized to treat non-communicable and infectious human diseases. Galanthamine, a drug from this family, is clinically relevant in treating the neurocognitive disorder, Alzheimer’s disease, which underscores the importance of the Amaryllidaceae alkaloids. Although Amaryllidaceae provide a plethora of biologically active compounds, there is tardiness in their development into clinically pliable medicines. Other genera, including Cyrtanthus and Tulbaghia, have received little attention as potential sources of promising drug candidates. Given the reciprocal relationship of the increasing burden of human diseases and limited availability of medicinal therapies, more rapid drug discovery and development are desirable. To expedite clinically relevant drug development, we present here evidence on bioactive compounds from the genera Allium, Tulgbaghia, Cyrtanthus and Crinum and describe their traditional and pharmacological applications.

Effects of Allium cepa and Its Constituents on Respiratory and Allergic Disorders: A Comprehensive Review of Experimental and Clinical Evidence

The health benefits of Allium cepa (A. cepa) have been proclaimed for centuries. Various pharmacological and therapeutic effects on respiratory, allergic, and immunologic disorders are shown by A. cepa and its constituents. Flavonoids such as quercetin and kaempferol, alk(en)yl cysteine sulfoxides including S-methyl cysteine sulfoxide and S-propyl cysteine sulfoxide, cycloalliin, thiosulfinates, and sulfides are the main compounds of the plant. A. cepa displays broad-spectrum pharmacological activities including antioxidant, anti-inflammatory, antihypertensive, and antidiabetic effects. Our objective in this review is to present the effects of A. cepa and its constituents on respiratory, allergic, and immunologic disorders. Different online databases were searched to find articles related to the effect of A. cepa extracts and its constituents on respiratory, allergic, and immunologic disorders until the end of December 2020 using keywords such as onion, A. cepa, constituents of A. cepa, therapeutic effects and pharmacological effects, and respiratory, allergic, and immunologic disorders. Extracts and constituents of A. cepa showed tracheal smooth muscle relaxant effects, indicating possible bronchodilator activities or relieving effects on obstructive respiratory diseases. In experimental animal models of different respiratory diseases, the preventive effect of various extracts and constituents of A. cepa was induced by their antioxidant, immunomodulatory, and anti-inflammatory effects. The preventive effects of the plant and its components on lung disorders induced by exposure to noxious agents as well as lung cancer, lung infection, and allergic and immunologic disorders were also indicated in the experimental and clinical studies. Therefore, this review may be considered a scientific basis for development of therapies using this plant, to improve respiratory, allergic, and immunologic disorders.

Pharmacological Properties of Allium cepa, Preclinical and Clinical Evidences; A Review

Onion or Allium cepa (A. cepa) is one of the most important condiment plants grown and consumed all over the world. This plant has various therapeutic effects attributed to its constituents, such as quercetin, thiosulphinates and phenolic acids. In the present article, various pharmacological and therapeutic effects of A. cepa were reviewed. Different online databases using keywords such as onion, A. cepa, therapeutic effects, and pharmacological effects until the end of December 2019 were searched for this purpose. Onion has been suggested to be effective in treating a broad range of disorders, including asthma, inflammatory disorders, dysentery, wounds, scars, keloids and pain. In addition, different studies have demonstrated that onion possesses numerous pharmacological properties, including anti-cancer, anti-diabetic and anti-platelet properties as well as the effect on bone, cardiovascular, gastrointestinal, nervous, respiratory, and urogenital systems effects such as anti-osteoporosis, anti-hypertensive, antispasmodic, anti-diarrheal, neuro-protective, anti-asthmatic and diuretic effects. The present review provides detailed the various pharmacological properties of onion and its constituents and possible underlying mechanisms. The results of multiple studies suggested the therapeutic effect of onion on a wide range of disorders.

An Herbal H2 Blocker in Melasma Treatment

BACKGROUND

Melasma is a skin pigmentation disorder that remains resistant to available therapies. The exact cause of melasma is unknown. Histamine is an inflammatory factor. Its involvement in pigmentation is obscure. The aim of this study is to introduce an herbal antihistamine H2 receptor which is effective in these disorders.

METHODS

This is a review study by searching the electronic databases and also Persian Medicine books, from 2000 to 2018 by the keywords such as H2 antagonist, H2 blocker and melasma.

RESULTS

According to the researched studies, histamine can induce melanogenesis and melasma after a series of stages in the body. Also, Histamine, through receptors 2, triggers melasma. Therefore, it can be said that antihistamine H2 receptor can be effective in melasma. Considering chemical antihistamine, H2 receptors have side effects, such as digestive problems, H2 antagonists can be used in the treatment of diseases such as dyspepsia but they have multiple complications. On the other hand, there is an herbal H2 antagonist that can be useful for melasma due to having some special properties.

CONCLUSION

Herbal H2 blockers should be noted in melasma treatment along with the topical drugs.

Allium porrum Extract Decreases Effector Cell Degranulation and Modulates Airway Epithelial Cell Function

Allium genus plants, such as leek (Allium porrum), are rich sources of anti-inflammatory and anti-oxidant secondary metabolites; this is of interest because it demonstrates their suitability as pharmacological alternatives for inflammatory processes, including allergy treatment. The composition of methanolic leek extract (LE) was analyzed by GC–MS and LC–IT/MS, and the total phenolic content and antioxidant capacity were quantified by colorimetric methods. Its pharmacological potential was analyzed in human bronchial epithelial Calu-3 cells, human mast cells LAD2, and humanized rat basophiles RBL-2H3. LE exhibited a cytotoxic effect on Calu-3 cells and HumRBL-2H3 cells only at high concentrations and in a dose-dependent manner. Moreover, LE decreased the degranulation of LAD2 and HumRBL-2H3 cells. LE treatment also significantly prevented alterations in transepithelial electrical resistance values and mRNA levels of glutathione-S-transferase (GST), c-Jun, and NFκB after treatment with H₂O₂ in ALI-cultured Calu-3 cells. Finally, ALI-cultured Calu-3 cells treated with LE showed lower permeability to Ole e 1 compared to untreated cells. A reduction in IL-6 secretion in ALI-cultured Calu-3 cells treated with LE was also observed. In summary, the results obtained in this work suggest that A. porrum extract may have potential anti-allergic effects due to its antioxidant and anti-inflammatory properties. This study provides several important insights into how LE can protect against allergy.

Therapeutic effect of topical administration of red onion extract in a murine model of allergic rhinitis

The aim of this study was to evaluate the effect of topical administration of onion (Allium cepa) extract on nasal cavity for treatment of allergic rhinitis (AR). BALB/c mice were sensitized by intraperitoneal injection of ovalbumin (OVA) and challenged with intranasal instillation of OVA with or without onion extracts for five times a week on 3 consecutive weeks. Allergic symptom score according to frequencies of sneezing, serum total and OVA specific immunoglobulin E (IgE) level, cytokine levels of nasal mucosa and eosinophilic infiltration were analyzed. Allergic symptom score, serum total and OVA specific IgE, cytokine levels of nasal mucosa (interleukin (IL)-4, IL-5, IL-10, IL-13, IFN-γ, TNF-α and COX-2) and eosinophilic infiltration were higher in allergic mouse group than negative control group. Topical application of onion extracts significantly reduced allergic symptoms and OVA specific IgE levels. Cytokine levels of IL-4, IL-5, IL-10, IL-13 and IFN-γ were significantly decreased in groups treated with onion extract. In addition, eosinophil infiltration of nasal turbinate mucosa was also significantly decreased after treatment with onion extract. Topical administration of onion extract significantly reduces allergic rhinitis symptom and allergic inflammatory reaction in a murine allergic model. It can be assumed that the topical application of onion extract regulates allergic symptoms by suppressing the type-1 helper (Th1) and type-2 helper (Th2) responses and reducing the allergic inflammatory reaction.

An overview of anti-diabetic plants used in Gabon: Pharmacology and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

The management of diabetes mellitus management in African communities, especially in Gabon, is not well established as more than 60% of population rely on traditional treatments as primary healthcare. The aim of this review was to collect and present the scientific evidence for the use of medicinal plants that are in currect by Gabonese traditional healers to manage diabetes or hyperglycaemia based here on the pharmacological and toxicological profiles of plants with anti-diabetic activity. There are presented in order to promote their therapeutic value, ensure a safer use by population and provide some bases for further study on high potential plants reviewed.

MATERIALS AND METHODS

Ethnobotanical studies were sourced using databases such as Online Wiley library, Pubmed, Google Scholar, PROTA, books and unpublished data including Ph.D. and Master thesis, African and Asian journals. Keywords including 'Diabetes', 'Gabon', 'Toxicity', 'Constituents', 'hyperglycaemia' were used.

RESULTS

A total of 69 plants currently used in Gabon with potential anti-diabetic activity have been identified in the literature, all of which have been used in in vivo or in vitro studies. Most of the plants have been studied in human or animal models for their ability to reduce blood glucose, stimulate insulin secretion or inhibit carbohydrates enzymes. Active substances have been identified in 12 out of 69 plants outlined in this review, these include Allium cepa and Tabernanthe iboga. Only eight plants have their active substances tested for anti-diabetic activity and are suitables for further investigation. Toxicological data is scarce and is dose-related to the functional parameters of major organs such as kidney and liver.

CONCLUSION

An in-depth understanding on the pharmacology and toxicology of Gabonese anti-diabetic plants is lacking yet there is a great scope for new treatments. With further research, the use of Gabonese anti-diabetic plants is important to ensure the safety of the diabetic patients in Gabon.

Italian folk plant-based remedies to heal headache (XIX-XX century)

BACKGROUND

Headache has been recognized since antiquity. From the late nineteenth to the early to mid-twentieth century, Italian folk remedies to treat headache were documented in a vast corpus of literature sources.

AIM

The purpose of this paper is to bring to light the plant-based treatments utilized by Italian folk medicine to heal headache in an attempt to discuss these remedies from a modern pharmacological point of view. Moreover, we compare the medical applications described by Hippocrates, Pliny the Elder, Dioscorides, Galen and Serenus Sammonicus with those utilized by Italian folk medicine to check if they result from a sort of continuity of use by over two thousand years.

RESULTS

A detailed search of the scientific data banks such as Medline and Scopus was undertaken to uncover recent results concerning the anti-inflammatory, anti-nociceptive and analgesic activities of the plants. Fifty-eight (78.4%) plant-based remedies have shown in vivo, in vitro or in human trials a large spectrum of anti-inflammatory, anti-nociceptive and analgesic activities. Moreover, thirty-one of remedies (41.9%) were already included in the pharmacopoeia between the 5th century BC and the 2nd century AD.

CONCLUSION

Italian folk medicine could be a promising source of knowledge and could provide evidences for active principles that have not as of yet been fully used for their potential.

Quercetin and Its Anti-Allergic Immune Response

Quercetin is the great representative of polyphenols, flavonoids subgroup, flavonols. Its main natural sources in foods are vegetables such as onions, the most studied quercetin containing foods, and broccoli; fruits (apples, berry crops, and grapes); some herbs; tea; and wine. Quercetin is known for its antioxidant activity in radical scavenging and anti-allergic properties characterized by stimulation of immune system, antiviral activity, inhibition of histamine release, decrease in pro-inflammatory cytokines, leukotrienes creation, and suppresses interleukin IL-4 production. It can improve the Th1/Th2 balance, and restrain antigen-specific IgE antibody formation. It is also effective in the inhibition of enzymes such as lipoxygenase, eosinophil and peroxidase and the suppression of inflammatory mediators. All mentioned mechanisms of action contribute to the anti-inflammatory and immunomodulating properties of quercetin that can be effectively utilized in treatment of late-phase, and late-late-phase bronchial asthma responses, allergic rhinitis and restricted peanut-induced anaphylactic reactions. Plant extract of quercetin is the main ingredient of many potential anti-allergic drugs, supplements and enriched products, which is more competent in inhibiting of IL-8 than cromolyn (anti-allergic drug disodium cromoglycate) and suppresses IL-6 and cytosolic calcium level increase.

Allium cepa L. and Quercetin Inhibit RANKL/Porphyromonas gingivalis LPS-Induced Osteoclastogenesis by Downregulating NF-κB Signaling Pathway

Objectives. We evaluated the in vitro modulatory effects of Allium cepa L. extract (AcE) and quercetin (Qt) on osteoclastogenesis under inflammatory conditions (LPS-induced). Methods. RAW 264.7 cells were differentiated with 30 ng/mL of RANKL, costimulated with PgLPS (1 µg/mL), and treated with AcE (50–1000 µg/mL) or Qt (1.25, 2.5, or 5 µM). Cell viability was determined by alamarBlue and protein assays. Nuclei morphology was analysed by DAPI staining. TRAP assays were performed as follows: p-nitrophenyl phosphate was used to determine the acid phosphatase activity of the osteoclasts and TRAP staining was used to evaluate the number and size of TRAP-positive multinucleated osteoclast cells. Von Kossa staining was used to measure osteoclast resorptive activity. Cytokine levels were measured on osteoclast precursor cell culture supernatants. Using western blot analysis, p-IκBα and IκBα degradation, inhibitor of NF-kappaB, were evaluated. Results. Both AcE and Qt did not affect cell viability and significantly reduced osteoclastogenesis compared to control. We observed lower production of IL-6 and IL-1α and an increased production of IL-3 and IL-4. AcE and Qt downregulated NF-κB pathway. Conclusion. AcE and Qt may be inhibitors of osteoclastogenesis under inflammatory conditions (LPS-induced) via attenuation of RANKL/PgLPS-induced NF-κB activation.

Potential therapeutic effect of Allium cepa L. and quercetin in a murine model of Blomia tropicalis induced asthma

BACKGROUND

Asthma is an inflammatory condition characterized by airway hyperresponsiveness and chronic inflammation. The resolution of inflammation is an essential process to treat this condition. In this study we investigated the effect of Allium cepa L. extract (AcE) and quercetin (Qt) on cytokine and on smooth muscle contraction in vitro and its therapeutic potential in a murine model of asthma.

METHODS

AcE was obtained by maceration of Allium cepa L. and it was standardized in terms of quercetin concentration using high performance liquid chromatography (HPLC). In vitro, using AcE 10, 100 or 1000 μg/ml or Qt 3.5, 7.5, 15 μg/ml, we measured the concentration of cytokines in spleen cell culture supernatants, and the ability to relax tracheal smooth muscle from A/J mice. In vivo, Blomia tropicalis (BT)-sensitized A/J mice were treated with AcE 100, 1000 mg/kg or 30 mg/kg Qt. We measured cell influx in bronchoalveolar lavage (BAL), eosinophil peroxidase (EPO) in lungs, serum levels of Bt-specific IgE, cytokines levels in BAL, and lung histology.

RESULTS

We observed a reduction in the production of inflammatory cytokines, a relaxation of tracheal rings, and a reduction in total number of cells in BAL and EPO in lungs by treatment with AcE or Qt.

CONCLUSION

AcE and Qt have potential as antiasthmatic drugs, as they possess both immunomodulatory and bronchodilatory properties.

Effect of Allium cepa L. on Lipopolysaccharide-Stimulated Osteoclast Precursor Cell Viability, Count, and Morphology Using 4',6-Diamidino-2-phenylindole-Staining

Allium cepa L. is known to possess numerous pharmacological properties. Our aim was to examine the in vitro effects of Allium cepa L. extract (AcE) on Porphyromonas gingivalis LPS and Escherichia coli LPS-stimulated osteoclast precursor cells to determine cell viability to other future cell-based assays. Osteoclast precursor cells (RAW 264.7) were stimulated by Pg LPS (1 μg/mL) and E. coli LPS (1 μg/mL) in the presence or absence of different concentrations of AcE (10-1000 μg/mL) for 5 days at 37°C/5% CO2. Resazurin reduction and total protein content assays were used to detect cell viability. AcE did not affect cell viability. Resazurin reduction assay showed that AcE, at up to 1000 μg/mL, did not significantly affect cell viability and cellular protein levels. Additionally a caspase 3/7 luminescence assay was used to disclose apoptosis and there was no difference in apoptotic activity between tested groups and control group. Fluorescence images stained by DAPI showed no alteration on the morphology and cell counts of LPS-stimulated osteoclast precursor cells with the use of AcE in all tested concentrations when compared to control. These findings suggest that Allium cepa L. extract could be used for in vitro studies on Porphyromonas gingivalis LPS and Escherichia coli LPS-stimulated osteoclast precursor cells.

Complementary therapies in allergic rhinitis

Objective. To determine the prevalence of herbal treatment of allergic rhinitis. Methods. In this prospective study, patients who were diagnosed with perennial allergic rhinitis were questioned about their use of natural products/herbal therapies for their symptoms. Results. In total, 230 patients were enrolled. Overall, 37.3% of the patients stated that they had used natural products/herbal therapies at least once. Women were more likely than men to use herbal supplements (38.3% versus 32.4%). Ten different types of herbal supplements were identified, with stinging nettle (Urtica dioicath), black elderberry (Sambucus nigra), and Spirulina being the most common (12.6%, 6.1%, and 5.7%, resp.). Conclusion. This study found a high prevalence of herbal treatment usage for the relief of allergic rhinitis symptoms in Turkey. The herbal products identified in this study and in the literature are discussed.

Hyaluronidase inhibiting activity and radical scavenging potential of flavonols in processed onion

The flavonol content and anti-inflammatory and antioxidant activities of onion treated by high-pressure processing (HPP) and HPP combined with freeze-drying and pulverization (HPP-FD-P) were evaluated. Allium cepa L. var. cepa, 'Recas' was treated at T1 (200 MPa/25 °C/5 min), T2 (400 MPa/25 °C/5 min), and T3 (600 MPa/25 °C/5 min). After treatment, HP-treated and untreated samples were frozen (diced onion, HP-treated). Subsequently, part of the diced samples was freeze-dried and pulverized (pulverized onion, HP-treated and freeze-dried). Flavonol content and anti-inflammatory and antioxidant activities (hyaluronidase inhibiting activity, NO(•), ABTS(•+), and DPPH(•) scavenging capacity, ferric reducing antioxidant power, and antioxidative capacity by photochemiluminescence) were measured in nonhydrolyzed and hydrolyzed extracts. Hydrolysis was carried out in order to evaluate the effect of HPP and HPP-FD-P on both anti-inflammatory and antioxidant activities of extracts mainly containing aglycone forms. HPP-FD-P increased quercetin 3,4'-diglucoside, quercetin 4'-glucoside, quercetin 3-glucoside, and isorhamnetin 3,4'-diglucoside extractability. The present study suggests that HPP (especially treatment at 400 MPa) and HPP-FD-P may be of benefit for obtaining functional ingredients from onion, as suggested by increased NO(•) scavenging capacity and maintenance of the antioxidant activity mainly in hydrolyzed extracts.

The activity of medicinal plants and secondary metabolites on eosinophilic inflammation

Eosinophils are leukocytes that are present in several body compartments and in the blood at relatively low numbers under normal conditions. However, an increase in the number of eosinophils, in the blood or in the tissues, is observed in allergic or parasitic disorders. Although some progress has been made in understanding the development of eosinophil-mediated inflammation in allergic and parasitic diseases, the discovery of new compounds to control eosinophilia has lagged behind other advances. Plant-derived secondary metabolites are the basis for many drugs currently used to treat pathologic conditions, including eosinophilic diseases. Several studies, including our own, have demonstrated that plant extracts and secondary metabolites can reduce eosinophilia and eosinophil recruitment in different experimental animal models. In this review, we summarize these studies and describe the anti-eosinophilic activity of various plant extracts, such as Ginkgo biloba, Allium cepa, and Lafoensia pacari, as well as those of secondary metabolites (compounds isolated from plant extracts), such as quercetin and ellagic acid. In addition, we highlight the medical potential of these plant-derived compounds for treating eosinophil-mediated inflammation, such as asthma and allergy.