Spasmogenic and spasmolytic activities of Agastache mexicana ssp. mexicana and A. mexicana ssp. xolocotziana methanolic extracts on the guinea pig ileum

Pharmacological disadvantages in the spasmolytic effects by using the mixture known as "three toronjiles" in folk medicine

ETHNOPHARMACOLOGY RELEVANCE

In Mexico, Agastache mexicana subsp. mexicana (PT) and subsp. xolocotziana (WT), and Dracocephalum moldavica (BT), are used together as the "three toronjiles" to treat gastrointestinal spasms.

AIM OF STUDY

To evaluate if the spasmolytic activity of these three medicinal species is better in combination or in an individual manner.

MATERIALS AND METHODS

Spasmolytic effect of PT, WT and BT alone or combinate were evaluated in rings of the guinea-pig ileum contracted with potassium chloride (KCl), electrical field stimulation (EFS), or acetylcholine (ACh). Chemical analysis by thin layer and ultra-high pressure liquid chromatography of the aqueous extracts of each species were done for their comparison, and their acute toxicity were determined in mice.

RESULTS

PT and WT diminished in a dose-dependent manner the contractions induced by KCl, EFS, and ACh. Whereas BT did not altered contractions in any experimental protocol. A combination of the PT (EC50) and WT (EC50) diminished the contractions induced by KCl or EFS. Interestingly, the addition of BT extract (10 μg/ml) to the combination (PT EC30 + WT EC30) blocked the inhibitory effect produced on the contracted tissue in the presence of KCl, EFS, or ACh. Moreover, addition of BT extract (100 μg/ml) to the same combination blocked the inhibitory effect on the pre-contracted tissue only in the presence of EFS. None of the aqueous extracts produced toxicity in its individual administration in mice. Chemical analysis demonstrated similarities between PT and WT, but differences with BT.

CONCLUSIONS

The results of this study confirmed that either combined or by themselves aqueous extracts of PT and WT produced a spasmolytic action on guinea pig ileum, suggesting that this combination of medicinal plants could relieve gastrointestinal diseases in human, but when BT aqueous extract is added to those obtained with PT and WT, the spasmolytic activity diminished or even was blocked. Our results give evidence that mixture of several plants might produce disadvantages in the medicinal properties of their individual activity.

Agastache Species: A Comprehensive Review on Phytochemical Composition and Therapeutic Properties

The Agastache genus is part of the Lamiaceae family and is native to North America, while one species, Agastache rugosa (A. rugosa), is native to East Asia. A review on the phytochemistry and bioactivity of Agastache genus was last performed in 2014. Since then, a lot of progress has been made on the characterization of the phytochemical and pharmacological profiles of Agastache species. Thus, the purpose of this paper is to present a summary of the findings on the phytochemistry and biological effects of several Agastache species, including both extracts and essential oil characterization. We performed a comprehensive search using PubMed and Scopus databases, following PRISMA criteria regarding the study selection process. The available data is focused mainly on the description of the chemical composition and bioactivity of A. rugosa, with fewer reports referring to Agastache mexicana (A. mexicana) and Agastache foeniculum (A. foeniculum). Agastache species are characterized by the dominance of flavonoids and phenolic acids, as well as volatile compounds, particularly phenylpropanoids and monoterpenes. Moreover, a series of pharmacological effects, including antioxidant, cytotoxic, antimicrobial, anti-atherosclerotic, and cardioprotective properties, have been reported for species from the Agastache genus.

Lamiaceae in Mexican Species, a Great but Scarcely Explored Source of Secondary Metabolites with Potential Pharmacological Effects in Pain Relief

The search for molecules that contribute to the relief of pain is a field of research in constant development. Lamiaceae is one of the most recognized families world-wide for its use in traditional medicine to treat diseases that include pain and inflammation. Mexico can be considered one of the most important centers of diversification, and due to the high endemism of this family, it is crucial for the in situ conservation of this family. Information about the most common genera and species found in this country and their uses in folk medicine are scarcely reported in the literature. After an extensive inspection in bibliographic databases, mainly Sciencedirect, Pubmed and Springer, almost 1200 articles describing aspects of Lamiaceae were found; however, 217 articles were selected because they recognize the Mexican genera and species with antinociceptive and/or anti-inflammatory potential to relieve pain, such as Salvia and Agastache. The bioactive constituents of these genera were mainly terpenes (volatile and non-volatile) and phenolic compounds such as flavonoids (glycosides and aglycone). The aim of this review is to analyze important aspects of Mexican genera of Lamiaceae, scarcely explored as a potential source of secondary metabolites responsible for the analgesic and anti-inflammatory properties of these species. In addition, we point out the possible mechanisms of action involved and the modulatory pathways investigated in different experimental models. As a result of this review, it is important to mention that scarce information has been reported regarding species of this family from Mexican genera. In fact, despite Calosphace being one of the largest subgenera of Salvia in the world, found mainly in Mexico, it has been barely investigated regarding its potential biological activities and recognized bioactive constituents. The scientific evidence regarding the different bioactive constituents found in species of Lamiaceae demonstrates that several species require further investigation in preclinical studies, and of course also in controlled clinical trials evaluating the efficacy and safety of these natural products to support their therapeutic potential in pain relief and/or inflammation, among other health conditions. Since Mexico is one of the most important centers of diversification, and due to the high endemism of species of this family, it is crucial their rescue, in situ conservation, and investigation of their health benefits.

Limonene from Agastache mexicana essential oil produces antinociceptive effects, gastrointestinal protection and improves experimental ulcerative colitis

ETHNOPHARMACOLOGY RELEVANCE

Agastache mexicana is a popular plant of great demand in folk medicine, essentially due to its calming properties and for alleviating arthritic, muscular and abdominal pain. Despite its spectrum for pain relief, pharmacological studies of its bioactive constituents have been barely investigated.

AIM OF THE STUDY

To evaluate protective properties of the A. mexicana and bioactive compounds improving pathological gastrointestinal conditions in rodents.

MATERIAL AND METHODS

Different doses of the essential oil of A. mexicana ssp. mexicana and ssp. xolocotziana (30-562.2 mg/kg, i.p.) and individual monoterpenes (3-300 mg/kg, i.p.) were evaluated in an abdominal pain model. The most active monoterpene limonene and sulfasalazine (reference drug, 100 mg/kg, p.o.) were also evaluated in the oxazolone-induced colitis model using an oral gavage, where some inflammatory cytokines were analyzed by enzyme-linked immunosorbent assays. Finally, colonic histological assessment and gastroprotection in the absolute ethanol-induced ulcer model were explored.

RESULTS

Our results demonstrated that the essential oil of both subspecies produced a significant reduction in the abdominal writhes, where monoterpenes limonene and pulegone were partially responsible bioactive metabolites. Limonene showed the major antinociceptive efficacy in the writhing test. It also significantly decreased hyperalgesia, pathological biomarkers, and colonic inflammatory cytokines in the oxazolone-induced colitis model, as well as prevention in gastric damage.

CONCLUSIONS

Present results provide scientific evidence to reinforce the use of A. mexicana in the traditional medicine for gastrointestinal conditions, mainly related to pain and inflammation, demonstrating the potential of monoterpenes as natural products in the therapeutics of gastrointestinal affections such as ulcer, colitis, and abdominal pain.

A Systematic Approach to Agastache mexicana Research: Biology, Agronomy, Phytochemistry, and Bioactivity

Mexico is the center of origin of the species popularly known as toronjil or lemon balm (Agastache mexicana Linton & Epling). Two subspecies have been identified and are commonly called purple or red (Agastache mexicana Linton & Epling subspecies. mexicana) and white (Agastache mexicana subspecies xolocotziana Bye, E.L. Linares & Ramamoorthy). Plants from these subspecies differ in the size and form of inflorescence and leaves. They also possess differences in their chemical compositions, including volatile compounds. Traditional Mexican medicine employs both subspecies. A. mexicana exhibits a broad range of pharmacological properties, such as anti-inflammatory, anxiolytic, and antioxidant. A systematic vision of these plant’s properties is discussed in this review, exposing its significant potential as a source of valuable bioactive compounds. Furthermore, this review provides an understanding of the elements that make up the species’ holistic system to benefit from lemon balm sustainably.

Mexican Plants and Derivates Compounds as Alternative for Inflammatory and Neuropathic Pain Treatment-A Review

Despite the availability of many anti-pain drugs, in the form of NSAIDs, steroids, gabapentinoids, opioids, and antidepressants, in this study we address the natural compounds belonging to the group of Mexican medicinal plants or "Mexican folk medicine", used for pain management in Mexico. Our interest in this subject is due to the growing idea that "natural is harmless" and to the large number of side effects exhibited in pharmacotherapy. The objective of this review was to document the scientific evidence about Mexican medicinal plants and their derivatives used for inflammatory and neuropathic pain treatment, as well as the mechanisms of action implicated in their antinociceptive effects, their possible adverse effects, and the main pharmacological aspects of each plant or compound. Our data review suggested that most studies on Mexican medicinal plants have used inflammatory experimental models for testing. The anti-pain properties exerted by medicinal plants lack adverse effects, and their toxicological assays report that they are safe to consume; therefore, more studies should be performed on preclinical neuropathic pain models. Moreover, there is no convincing evidence about the possible mechanisms of action involved in the anti-pain properties exerted by Mexican plants. Therefore, the isolation and pharmacological characterization of these plant derivatives' compounds will be important in the design of future preclinical studies.

Study of Antispasmodic and Antidiarrheal Activities of Tagetes lucida (Mexican Tarragon) in Experimental Models and Its Mechanism of Action

Tagetes lucida has been used in traditional medicine as a remedy to alleviate several gastrointestinal disorders that provoke stomachaches, abdominal cramps, and diarrhea. However, there is not enough scientific evidence that supports these effects. Therefore, the purpose of this study was to evaluate antispasmodic and antidiarrheal activities of aqueous extract of T. lucida (AqExt-TL) as well as its mechanism of action in experimental models. Antispasmodic activity and the mechanism of action of AqExt-TL were assessed on segments of the guinea pig ileum precontracted with KCl, acetylcholine (ACh), or electrical field stimulation (EFS). Furthermore, the antispasmodic effect of two coumarins (umbelliferone and herniarin) previously identified in this species was evaluated. Antidiarrheal activity of AqExt-TL was determined using the charcoal meal test in mice. AqExt-TL showed antispasmodic activity in segments of the guinea pig ileum precontracted with KCl (83.7 ± 1.9%) and ACh (77.2 ± 5.3%) at the maximal concentration; however, practically, it did not alter the contractions induced by EFS (10.1 ± 2.2%). Antispasmodic activity of AqExt-TL was not significantly altered by hexamethonium (a ganglionic blocker) or L-NAME (an inhibitor of nitric oxide synthase). However, this extract decreased the maximal contractile response to calcium (82.7 ± 8.5%), serotonin (68.1 ± 8.5%), and histamine (63.9 ± 5.9%) in their concentration-response curves. Umbelliferone and herniarin also induced an antispasmodic effect on tissues precontracted with KCl. In addition, low doses of AqExt-TL reduced to 50% the distance traveled by charcoal meal in the gastrointestinal transit model in mice as loperamide, an antidiarrheal agent, did. These results provided evidence of the antispasmodic and antidiarrheal activity of T. lucida, which supports its use in the folk medicine in relieving symptoms in some gastrointestinal disorders. In the antispasmodic effect, the blockade of histaminergic and serotoninergic pathway as well as the calcium channels seems to be involved. Finally, umbelliferone and herniarin could be partially responsible for the antispasmodic activity induced by T. lucida.

Acacetin, a flavone with diverse therapeutic potential in cancer, inflammation, infections and other metabolic disorders

BACKGROUND

Acacetin is a di-hydroxy and mono-methoxy flavone present in various plants, including black locust, Damiana, Silver birch. Literature information revealed that acacetin exhibits an array of pharmacological potential including chemopreventive and cytotoxic properties in cancer cell lines, prevents ischemia/reperfusion/myocardial infarction-induced cardiac injury, lipopolysaccharide (LPS), 1-methyl-4-phenyl pyridinium ion (MPP+) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-induced neuroinflammation, LPS and sepsis-induced lung injury, rheumatoid and collagen-induced arthritis, inhibit the microbial growth, obesity, viral-mediated infections as well as hepatic protection.

PURPOSE

This review highlights the therapeutic potential of acacetin, with updated and comprehensive information on the biological sources, chemistry, and pharmacological properties along with the possible mechanism of action, safety aspects, and future research opportunities.

STUDY DESIGN

The information was retrieved from various search engines, including Pubmed, SciFinder, Science direct, Inxight:drugs, Google scholar, and Meta cyc.

RESULT

The first section of this review focuses on the detailed biological source of acacetin, chromatographic techniques used for isolation, chemical characteristics, the method for the synthesis of acacetin, and the available natural and synthetic derivatives. Subsequently, the pharmacological activities, including anti-cancer, anti-inflammatory, anti-viral, anti-microbial, anti-obesity, have been discussed. The pharmacokinetics data and toxicity profile of acacetin are also discussed.

CONCLUSION

Acacetin is a potent molecule reported for its strong anti-inflammatory and anti-cancer activity, however further scientific evidence is essential to validate its potency in disease models associated with inflammation and cancer. There is limited information available for toxicity profiling of acacetin; therefore, further studies would aid in establishing this natural flavone as a potent candidate for research studies at clinical setup.

High accumulation of tilianin in in-vitro cultures of Agastache mexicana and its potential vasorelaxant action

Agastache mexicana has gained importance during the last decade as a natural source of bioactive compounds, mainly due to the antidiabetic, antihyperlipidemic, and vasorelaxant effects derived from its flavonoids, particularly tilianin. The goal of this work was to evaluate the production of tilianin during the in-vitro process of morphogenesis leading to plant regeneration and to investigate the vasorelaxant activity of its methanolic extracts. The cultures were established from nodal segments and leaf explants, inoculated on Murashige and Skoog (MS) media supplemented with various concentrations of benzyl aminopurine (BAP) alone or in combination with 2,4-Dichlorophenoxyacetic acid (2,4-D). Callus inductions were obtained in all treatments from both types of explants, but the presence of auxin was essential. Maximal shoot multiplication and elongation was achieved with 0.1 mg/l 2,4-D and 1.0 mg/l BAP from nodal- segment explants. Shoots were rooted in 75% MS medium and the plantlets were transferred to a greenhouse with 33% average survival. Analysis of tilianin production in methanolic extracts from calli (0.15-2.01 ± 0.06 mg/g dry weight), shoots (4.45 ± 0.01 mg/g DW), and whole plants (9.77 ± 0.02 mg/g DW) derived from in-vitro cultured nodal segments reveals that tilianin accumulation is associated with high cell differentiation and morphogenetic response to the plant-growth regulators. All of the extracts showed strong vasorelaxant activity, as compared to those of wild plant extracts. These results indicate that plant-tissue cultures of A. mexicana possess vast potential as a source of tilianin and other bioactive compounds.

Spasmolytic effect of aqueous extract of Tagetes erecta L. flowers is mediated through calcium channel blockade on the guinea-pig ileum

This study provides pharmacological evidence on the spasmolytic activity of Tagetes erecta L. (marigold or cempasúchil) on the guinea-pig ileum and presents data on its mechanism of action. The relaxant effect on KCl contractions was more marked with aqueous (AqEx) than with ethanol extracts (EtEx) of T. erecta flowers (55.6 ± 11.0 vs 21.1 ± 4.4%, respectively). In addition, the aqueous extract antagonized contractions elicited by EFS, but not by acetylcholine (73.5 ± 1.9 vs 14.5 ± 5.3%, respectively). These effects were not diminished by hexamethonium or L-NAME, but this extract caused a rightward shift in the Ca²⁺ concentration-response curves like that of verapamil. Quercetin and rutin, two flavonoids present in this plant, also showed spasmolytic effects (95.7 ± 2.8 and 27.9 ± 7.1%, respectively). Interestingly, in tissues without spasmogens, the extract induced contractions superimposed on their spontaneous activity. These results support the traditional use of T. erecta as a spasmolytic in folk medicine and suggest mainly that quercetin could be partly responsible for this effect. The spasmolytic effect appears to involve voltage-gated calcium channels, but not the nitric oxide pathway or the release of neurotransmitters from enteric neurons. Nevertheless, this plant could produce colic or stomachache as adverse effects in clinical situations in which these symptoms are not originally present.