Investigation into the mechanism of action of essential oil of Pistacia integerrima for its antiasthmatic activity

Al-Awthan Y, Muhammad N, Mukarram Shah M, Mitra S, Bin Emran T, Bahattab O, S. Mubarak M. Pharmacological Investigation of Genus Pistacia

Several plants in the genus Pistacia are used in the treatment of various pathogenic and non-pathogenic disorders. Especially important are the major species belonging to this genus such as Pistacia lentiscus, Pistacia atlantica, Pistacia vera, Pistacia terebinthus, and Pistacia khinjuk, among others; these have been reported for their potential benefits both in medical and commercial purposes. In addition, members of this genus exhibit numerous ethnomedicinal uses, such as analgesic, anti-inflammatory, anticancer, antimicrobial, antihypertension, antihyperlipidemic, antiviral, and antiasthma. In light of these potential uses, the present chapter aimed to collect and summarize the literature about all of this medicinal information. Accordingly, this chapter focuses on the pharmacological uses and benefits of the genus Pistacia, especially those related to health issues.

Potent In Vitro Phosphodiesterase 1 Inhibition of Flavone Isolated from Pistacia integerrima Galls

To prospect an isozyme-specific, effective inhibitor against the physiologically-crucial enzyme phosphodiesterase 1 (PDE1), phytochemicals from Pistacia integerrima galls were screened. The chloroform fraction of gall extract was subjected to column chromatographic which led to the isolation of compound 1, elucidated to be 5-hydroxy-7-methoxy-2-(4-methoxyphenyl)-4H-chromen-4-one (a flavone). In vitro and in silico PDE1 inhibitory activity of the compound 1 was investigated. EDTA, a known PDE1 inhibitor, was used as the reference. The flavone exhibited in vitro attenuation towards snake venom PDE1. IC₅₀ response was superior to the standard chelator. An in silico molecular docking study was carried out using 3D structure of PDE1 to study the binding interactions of compound 1. The docking study predicted that flavone had a lower binding affinity (-7.6 kcal/mol) and total energy (-95 kcal/mol) score compared to EDTA. The minimal energy associated with the ligand-protein complex implied that isolated compound 1 can serve as a therapeutic agent against PDE1 enzyme-provoked ailments like asthma, hypertension, schizophrenia, and erectile dysfunction.

Modulation of neutrophil (dys)function by Ayurvedic herbs and its potential influence on SARS-CoV-2 infection

For centuries, traditional medicines of Ayurveda have been in use to manage infectious and non-infectious diseases. The key embodiment of traditional medicines is the holistic system of approach in the management of human diseases. SARS-CoV-2 (COVID-19) infection is an ongoing pandemic, which has emerged as the major health threat worldwide and is causing significant stress, morbidity and mortality. Studies from the individuals with SARS-CoV-2 infection have shown significant immune dysregulation and cytokine overproduction. Neutrophilia and neutrophil to lymphocyte ratio has been correlated to poor outcome due to the disease. Neutrophils, component of innate immune system, upon stimulation expel DNA along with histones and granular proteins to form extracellular traps (NETs). Although, these DNA lattices possess beneficial activity in trapping and eliminating pathogens, NETs may also cause adverse effects by inducing immunothrombosis and tissue damage in diseases including Type 2 Diabetes and atherosclerosis. Tissues of SARS-CoV-2 infected subjects showed microthrombi with neutrophil-platelet infiltration and serum showed elevated NETs components, suggesting large involvement and uncontrolled activation of neutrophils leading to pathogenesis and associated organ damage. Hence, traditional Ayurvedic herbs exhibiting anti-inflammatory and antioxidant properties may act in a manner that might prove beneficial in targeting over-functioning of neutrophils and there by promoting normal immune homeostasis. In the present manuscript, we have reviewed and discussed pathological importance of NETs formation in SARS-CoV-2 infections and discuss how various Ayurvedic herbs can be explored to modulate neutrophil function and inhibit NETs formation in the context of a) anti-microbial activity to enhance neutrophil function, b) immunomodulatory effects to maintain neutrophil mediated immune homeostasis and c) to inhibit NETs mediated thrombosis.

Calcio-herbal formulation, Divya-Swasari-Ras, alleviates chronic inflammation and suppresses airway remodelling in mouse model of allergic asthma by modulating pro-inflammatory cytokine response

Asthma is a chronic allergic respiratory disease with limited therapeutic options. Here we validated the potential anti-inflammatory, anti-asthmatic and immunomodulatory therapeutic properties of calcio-herbal ayurvedic formulation, Divya-Swasari-Ras (DSR) in-vivo, using mouse model of ovalbumin (OVA) induced allergic asthma. HPLC analysis identified the presence of various bioactive indicating molecules and ICP-OES recognized the presence of Ca mineral in the DSR formulation. Here we show that DSR treatment significantly reduced cardinal features of allergic asthma including inflammatory cell accumulation, specifically lymphocytes and eosinophils in the Broncho-Alveolar Lavage (BAL) fluids, airway inflammation, airway remodelling, and pro-inflammatory molecules expression. Conversely, number of macrophages recoverable by BAL were increased upon DSR treatment. Histology analysis of mice lungs revealed that DSR attenuates inflammatory cell infiltration in lungs and thickening of bronchial epithelium. PAS staining confirmed the decrease in OVA-induced mucus secretion at the mucosal epithelium; and trichrome staining confirmed the decrease in peribronchial collagen deposition upon DSR treatment. DSR reduced the OVA-induced pro-inflammatory cytokines (IL-6, IL-1β and TNF-α) levels in BALF and whole lung steady state mRNA levels (IL-4, -5, -33, IFN-γ, IL-6 and IL-1β). Biochemical assays for markers of oxidative stress and antioxidant defence mechanism confirmed that DSR increases the activity of SOD, Catalase, GPx, GSH, GSH/GSSG ratio and decreases the levels of MDA activity, GSSG, EPO and Nitrite levels in whole lungs. Collectively, present study suggests that, DSR effectively protects against allergic airway inflammation and possess potential therapeutic option for allergic asthma management.

Antispasmodic Effect of Essential Oils and Their Constituents: A Review

The antispasmodic effect of drugs is used for the symptomatic treatment of cramping and discomfort affecting smooth muscles from the gastrointestinal, billiary or genitourinary tract in a variety of clinical situations.The existing synthetic antispasmodic drugs may cause a series of unpleasant side effects, and therefore the discovery of new molecules of natural origin is an important goal for the pharmaceutical industry. This review describes a series of recent studies investigating the antispasmodic effect of essential oils from 39 plant species belonging to 12 families. The pharmacological models used in the studies together with the mechanistic discussions and the chemical composition of the essential oils are also detailed. The data clearly demonstrate the antispasmodic effect of the essential oils from the aromatic plant species studied. Further research is needed in order to ascertain the therapeutic importance of these findings.

Essential Oils and Their Major Compounds in the Treatment of Chronic Inflammation: A Review of Antioxidant Potential in Preclinical Studies and Molecular Mechanisms

Inflammatory diseases result from the body's response to tissue damage, and if the resolution is not adequate or the stimulus persists, there will be progression from acute inflammation to chronic inflammation, leading to the development of cancer and neurodegenerative and autoimmune diseases. Due to the complexity of events that occur in inflammation associated with the adverse effects of drugs used in clinical practice, it is necessary to search for new biologically active compounds with anti-inflammatory activity. Among natural products, essential oils (EOs) present promising results in preclinical studies, with action in the main mechanisms involved in the pathology of inflammation. The present systematic review summarizes the pharmacological effects of EOs and their compounds in in vitro and in vivo models for inflammation. The research was conducted in the following databases: PubMed, Scopus, BIREME, Scielo, Open Grey, and Science Direct. Based on the inclusion criteria, 30 articles were selected and discussed in this review. The studies listed revealed a potential activity of EOs and their compounds for the treatment of inflammatory diseases, especially in chronic inflammatory conditions, with the main mechanism involving reduction of reactive oxygen and nitrogen species associated with an elevation of antioxidant enzymes as well as the reduction of the nuclear factor kappa B (NF-κB), reducing the expression of proinflammatory cytokines. Thus, this review suggests that EOs and their major compounds are promising tools for the treatment of chronic inflammation.

The relevance of folkloric usage of plant galls as medicines: Finding the scientific rationale

Galls, the abnormal growths in plants, induced by virus, bacteria, fungi, nematodes, arthropods, or even other plants, are akin to cancers in fauna. The galls which occur in a myriad of forms are phytochemically-distinct from the normal plant tissues, for these are the sites of tug-of-war, just like the granuloma in animals. To counter the stressors, in the form of the effector proteins of the invaders, the host plants elaborate a large repertoire of metabolites, which they normally will not produce. Perturbation of the jasmonic acid pathway, and the overexpression of auxin, and cytokinin, promote the tissue proliferation and the resultant galls. Though the plant family characteristics and the attackers determine the gall biochemistry, most of the galls are rich in bioactive phytochemicals such as phenolic acids, anthocyanins, purpurogallin, flavonoids, tannins, steroids, triterpenes, alkaloids, lipophilic components (tanshinone) etc. Throughout the long trajectory of evolution, humans have learned to use the galls as therapeutics, much like other plant parts. In diverse cultures, the evidence of folkloric usage of galls abound. Among others, galls from the plant genus like Rhus, Pistacia, Quercus, Terminalia etc. are popular as ethnomedicine. This review mines the literature on galling agents, and the medicinal relevance of galls.

In Vitro Evaluation of the Antioxidant, Cytoprotective, and Antimicrobial Properties of Essential Oil from Pistacia vera L. Variety Bronte Hull

Although the chemical composition and biological properties of some species of the genus Pistacia has been investigated, studies on hull essential oil of Pistacia vera L. variety Bronte (HEO) are currently lacking. In this work, we have carried out an in-depth phytochemical profile elucidation by Gas Chromatography-Mass Spectrometry (GC-MS) analysis, and an evaluation of antioxidant scavenging properties of HEO, using several different in vitro methods, checking also its cytoprotective potential on lymphocytes treated with tert-butyl hydroperoxide. Moreover, the antimicrobial activity against Gram-positive and Gram-negative strains, both American Type Culture Collection (ATCC) and clinical isolates, was also investigated. GC-MS analysis highlighted the richness of this complex matrix, with the identification of 40 derivatives. The major components identified were 4-Carene (31.743%), α-Pinene (23.584%), d-Limonene (8.002%), and 3-Carene (7.731%). The HEO showed a strong iron chelating activity and was found to be markedly active against hydroxyl radical, while scarce effects were found against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Moreover, pre-treatment with HEO was observed to significantly increase the cell viability, decreasing the lactate dehydrogenase (LDH) release. HEO was bactericidal against all the tested strains at the concentration of 7.11 mg/mL, with the exception of Pseudomonas aeruginosa ATCC 9027. The obtained results demonstrate the strong free-radical scavenging activity of HEO along with remarkable cytoprotective and antimicrobial properties.

Phytochemical, ethnomedicinal uses and pharmacological profile of genus Pistacia

Pistacia genus belong to family Anacardiaceae and it is versatile in that its member species have food (P. vera), medicinal (P. lentiscus) and ornamental (P. chinensis) values. Various species of this genus have folkloric uses with credible mention in diverse pharmacopeia. As a trove of phenolic compounds, terpenoids, monoterpenes, flavonoids, alkaloids, saponins, fatty acids, and sterols, this genus has garnered pharmaceutical attention in recent times. With adequate clinical studies, this genus might be exploited for therapy of a multitude of inflammatory diseases, as promised by preliminary studies. In this regard, the ethnomedicinal, phytochemistry, biological potencies, risks, and scopes of Pistacia genus have been reviewed here.

Pistacia integerrima ameliorates airway inflammation by attenuation of TNF-α, IL-4, and IL-5 expression levels, and pulmonary edema by elevation of AQP1 and AQP5 expression levels in mouse model of ovalbumin-induced allergic asthma

BACKGROUND

Natural products are considered as an essential source for the search of new drugs. Pistacia integerrima galls (PI) have been used for the treatment of asthma and cough in traditional system of medicine.

AIM/HYPOTHESIS

Current study investigates the immunomodulatory and anti-inflammatory activities of P. integerrima in mouse model of ovalbumin-induced allergic asthma.

METHODS

Mice were intraperitoneally sensitized and subsequently challenged intranasally with ovalbumin to induce allergic asthma. Experimental group mice were treated with methanol extract of P. integerrima extract (200mg/kg b. w.) and Methylprednisolone (MP) (15mg/kg b. w.) for 07 consecutive days, alongside intranasal challenge. Lung tissues were stained with Hematoxyline and Eosin (H & E), and Periodic Acid-Schiff (PAS) stains for histopathological evaluation. Lung wet/dry weight ratio was measured as an index of lung tissue edema. Albumin was injected in the right ear 24h before sacrificing the mice and difference of weight was taken as a degree of delayed type hypersensitivity (DTH). mRNA expression levels of TNF-α, IL-4, IL-5, Aquaporin-1 (AQP1), and AQP5 were evaluated using reverse transcription polymerase chain reaction (RT-PCR) followed by gel electrophoresis.

RESULTS

The data showed both PI extract and MP significantly alleviated DTH and nearly normalized total leukocyte count and differential leukocyte count in both blood and BALF. We found significantly suppressed goblet cell hyperplasia and inflammatory cell infiltration after treatment with both PI extract and MP. Expression levels of TNF-α, IL-4, and IL-5 were also found significantly reduced after treatment with both PI extract and MP, which might have resulted in the amelioration of airway inflammation. Current study displayed that both PI extract and MP significantly decreased lung wet/dry ratio, suggesting reduction in pulmonary edema. RT-PCR analysis showed significant increase in AQP1 and AQP5 expression levels after treatment with both PI extract and MP, which might have caused the alleviation of pulmonary edema.

CONCLUSION

Our study displays that P. integerrima possesses significant anti-asthmatic activity which may be attributed to reduction in TNF-α, IL-4, and IL-5 expression levels, and increase in AQP1 and AQP5 expression levels.

Antispasmodic Effects and Action Mechanism of Essential Oil of Chrysactinia mexicana A. Gray on Rabbit Ileum

The Chrysactinia mexicana A. Gray (C. mexicana) plant is used in folk medicine to treat fever and rheumatism; it is used as a diuretic, antispasmodic; and it is used for its aphrodisiac properties. This study investigates the effects of the essential oil of C. mexicana (EOCM) on the contractility of rabbit ileum and the mechanisms of action involved. Muscle contractility studies in vitro in an organ bath to evaluate the response to EOCM were performed in the rabbit ileum. EOCM (1-100 µg·mL(-1)) reduced the amplitude and area under the curve of spontaneous contractions of the ileum. The contractions induced by carbachol 1 µM, potassium chloride (KCl) 60 mM or Bay K8644 1 µM were reduced by EOCM (30 µg·mL(-1)). Apamin 1 µM and charybdotoxin 0.01 µM decreased the inhibition induced by EOCM. The d-cAMP 1 µM decreased the inhibition induced by EOCM. l-NNA 10 µM, Rp-8-Br-PET-cGMPS 1 µM, d,l-propargylglycine 2 mM, or aminooxyacetic acid hemihydrochloride 2 mM did not modify the EOCM effect. In conclusion, EOCM induces an antispasmodic effect and could be used in the treatment of intestinal spasms or diarrhea processes. This effect would be mediated by Ca(2+), Ca(2+)-activated K⁺ channels and cAMP.

Essential oils in the treatment of respiratory tract diseases highlighting their role in bacterial infections and their anti-inflammatory action: a review

The appearance of multidrug resistant bacteria and growing antibiotic resistance is leading to a continuous need for discovering new drugs and alternative treatments against infections. The investigation of the antibacterial effect of essential oils (EOs), which are commonly used nowadays in cosmetics, health care, traditional medicine and food industry, could be one of the promising solutions for this worldwide problem. EOs have a complex mode of action due to their multiple composition. Respiratory tract diseases (RTDs) associated with bacterial infection and inflammation affect a large number of people from every age group worldwide. Because of volatility, EOs can easily reach the upper and lower parts of the respiratory tract via inhalation. Moreover, due to their antimicrobial and anti-inflammatory potency, they offer an effective treatment in respiratory tract infections (RTIs). The purpose of this review is to describe the most frequently developing infections of the upper and lower respiratory tract and to show methods used for the determination of the antibacterial activity of EOs by gaseous contact. The mode of action of EOs on bacterial cells and their anti-inflammatory action are also discussed. Results coming from recently performed in vivo animal studies as well as human trials are also reported. Patents deal with the role of EOs and their volatile constituents in the treatment of RTIs are also introduced. On the whole, this review aimed at showing EOs as potential antimicrobials and as anti-inflammatory agents to alleviate symptoms and signs of RTDs including RTIs. Copyright © 2015 John Wiley & Sons, Ltd.

Assessment of the Mechanistic Role of Cinnarizine in Modulating Experimentally-Induced Bronchial Asthma in Rats

BACKGROUND/AIMS

Calcium influx, inflammatory infiltration, cytokine production, immunoglobulin E activation and oxidative stress play coordinated roles in bronchial asthma pathogenesis. We aim to assess the protective effect of cinnarizine against experimentally induced bronchial asthma.

METHODS

Bronchial asthma was induced by ovalbumin sensitization and challenge. Rats were allocated into a normal control, an asthma control, a dexamethasone (standard) treatment, and 2 cinnarizine treatment groups. The respiratory functions tidal volume (TV) and peak expiratory flow rate (PEFR), the inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and interleukin-5 (IL-5) in lung tissue, the allergic immunoglobulin IgE in serum, the absolute eosinophil count (AEC) in bronchoalveolar lavage fluid (BALF), as well as the oxidative and nitrosative markers glutathione reduced (GSH) and superoxide dismutase (SOD) in lung tissue and nitric oxide end products (NOx) in BALF were assessed, followed by a histopathological study.

RESULTS

Cinnarizine administration significantly restored TV, PEFR, TNF-α, IL-5, IgE, AEC, GSH, SOD and NOx values back to normal levels, and significantly decreased perivascular and peribronchiolar inflammatory scores.

CONCLUSION

Cinnarizine may protect against experimental bronchial asthma. Suppressant effect of cinnarizine on pro-inflammatory cytokines release, IgE antibody production, eosinophil infiltration as well as oxidative and nitrosative stress may explain its anti-asthmatic potential.

In vitro relaxant and spasmolytic effects of essential oil of Pistacia integerrima Stewart ex Brandis Galls

ETHNOPHARMACOLOGICAL RELEVANCE

Pistacia integerrima J.L. Stewart ex Brandis (Family: Anacardiaceae) galls are used in Indian ethnomedicine for its anti-asthmatic, sedative and spasmolytic properties, however, there are no scientific studies demonstrating its spasmolytic activity. The present investigation deals with the evaluation of relaxant and spasmolytic activities of the essential oil isolated from the galls of Pistacia integerrima J.L. Stewart ex Brandis (EOPI).

MATERIALS AND METHODS

In vitro pharmacological assays were carried out on rabbit jejunum spontaneous contractions, guinea pig ileum. The present investigation studied the relaxation of basal tone of isolated guinea pig ileum by possible involvement of NO, prostaglandins, membrane Na(+) channels, potassium channel, enteric nervous system, adrenoceptors, Ca(2+) channels. Additional studies were conducted for comparison of the relaxant effects of EOPI on CaCl2 induced contraction in calcium free tyrode solution, effect on nifedipine insensitive component of ACh-induced contraction and on the contractile machinery to intracellular [Ca(2+)] on isolated guinea pig ileum.

RESULTS

EOPI at non-relaxing dose potentiated the isoprenaline induced relaxation of rabbit jejunum. EOPI (50 µg/mL) exhibited 28% relaxation of basal tone of 60 mM K(+) induced contraction which is unaltered by preincubation with 0.5 mM hexamethonium, 0.5 µM Tetrodotoxin, 1 µM indomethacin, and 100 µM L-NG-Nitroarginine Methyl Ester (L-NAME). EOPI inhibited Ca(2+) induced contraction of isolated guinea pig ileum in Ca(2+) free medium. EOPI (10 µg/ml) potentiated the reversal of a KCl-induced tonic contraction has been observed in Ca(2+) free medium.

CONCLUSION

The present investigation reinforces the use of Pistacia integerrima Stewart ex Brandis as antispasmodic in folk medicine. Moreover, it is demonstrated the involvement of β- adrenoceptors and calcium channels in this activity, but not the participation of nicotinic receptors, Na(+) channels, prostaglandins or nitric oxide.

Phosphodiesterase-1 Inhibitory Activity of Two Flavonoids Isolated from Pistacia integerrima J. L. Stewart Galls

Pistacia integerrima is one of twenty species among the genus Pistacia. Long horn-shaped galls that develop on this plant are harvested and used in Ayurveda and Indian traditional medicine to make "karkatshringi", a herbal medicine used for the treatment of asthma and different disorders of respiratory tract. However, until now, the molecular mechanisms of action of "karkatshringi" and its chemical characterization are partially known. This study deals with the isolation and characterization of the active constituents from the methanolic extract of P. integerrima galls and it was also oriented to evaluate in vitro and in silico their potential enzymatic inhibitory activity against phosphodiesterase-1 (PDE1), a well-known enzyme involved in airway smooth muscle activity and airway inflammation. Our results showed that the methanolic extract of P. integerrima galls and some of its active constituents [naringenin (1) and 3,5,7,4'-tetrahydroxy-flavanone (2)] are able in vitro to inhibit PDE1 activity (59.20 ± 4.95%, 75.90 ± 5.90%, and 65.25 ± 5.25%, resp.) and demonstrate in silico an interesting interaction with this enzymatic site. Taken together, our results add new knowledge of chemical constituents responsible for the biological activity of P. integerrima and contextually legitimate the use of this plant in folk medicine.