Myorelaxant and antispasmodic effects of the essential oil of Artemisia campestris L., and the molecular docking of its major constituents with the muscarinic receptor and the L-type voltage-gated Ca2+channel.

ETHNOPHARMACOLOGICAL RELEVANCE: Gastrointestinal disorders are among the most common diseases that cause discomfort to people who are affected. In Morocco, aromatic and medicinal plants are widely used to calm these pains and eliminate their symptoms. Among these plants, Artemisia campestris L. which is used in eastern Morocco to treat digestive system problems. AIM OF THE STUDY: Our study aimed to experimentally verify the traditional use of this plant by evaluating the myorelaxant and antispasmodic effects of the essential oil of Artemisia campestris L. (EOAc). MATERIALS AND METHODS: Gas Chromatography-Mass Spectrometry analysis (GC-MS) was performed to identify the compounds present in the EOAc. Then, these molecules were subjected to the in silico study for molecular docking. The myorelaxant and antispasmodic evaluation of the EOAc were tested in vitro on an isolated rabbit and rat jejunum mounted on an organ bath. Then, an isotonic transducer connected to an amplifier recorded the graph related to intestinal contractility. RESULTS: GC-MS analysis of the essential oil of Artemisia campestris L. showed the presence of m-Cymene (17.308%), Spathulenol (16.785%), ß Pinene (15.623%), α Pinene (11.352%), α.-Campholenal (8.848%) as main constituents. The EOAc gave a dose-dependent and reversible myorelaxant effect on the spontaneous contractions of jejunum isolated from rabbits, with an IC50 equal to 72.16 ± 15.93 µg/mL. This effect did not occur through adrenergic receptors. The EOAc has an antispasmodic effect on the contractions of rat jejunal induced by a medium with low (25 mM) or high concentration (75 mM) of KCl, and carbachol 10-6 M. The obtained inhibitory effects are comparable to those of a non-competitive antagonist of cholinergic receptors. The major compounds of EOAc allowed the establishment of a relationship between these phytoconstituents and the antispasmodic effect found by the EOAc. The obtained results are also supported by a docking study. CONCLUSION: The obtained results confirm favorably the use of Artemisia campestris L. in traditional Moroccan medicine for the treatment of digestive tract illness, which gives us a new route to valorize the effects obtained by a phytomedicine specific for the digestive tract.

Antioxidant Activity and Inhibition of Carbohydrate Digestive Enzymes Activities of Artemisia campestris L.

BACKGROUND: Carbohydrate digestive enzymes play a major role in the management of the postprandial hyperglycemia. A chronic hyperglycemia can lead to serious health problems due to excessive production of several reactive oxygen species. Therefore, the inhibition of carbohydrate digestive enzyme and the use of antioxidant natural product can be an important strategy to control the glycaemia level and prevent against the complication of diabetes. AIM: The study aims to perform a phytochemical analysis, antioxidant activity, inhibitory effect on α -amylase, α -glucosidase (in vitro and in vivo) and the intestinal glucose absorption in Wistar rats of Artemisia campestris aqueous extract (AcAE) and hydro-ethanolic extract (AcEE). RESULTS: The test of total phenolic content, show that the AcAE has the highest quantity of polyphenol (44.65 ± 0.54 µ g GAE/mg extract) compared to the AcEE (31.7 ± 0.53 µ g GAE/mg extract) significantly. The amount of flavonoid and condensed tannins content in AcAE is 24.41 ± 3.57 µ g QrE/mg extract, 14.31 ± 5.26 µ g CE/mg respectively. The AcAE has also exhibit a great antioxidant activity in DPPH-scavenging and Ferric reducing antioxidant power assay (FRAP) compared to AcEE with an IC 50 = 0.355 ± 0.057 mg/mL and IC 50 = 0.269 ± 0.025 mg/mL. However, in a ß -carotene bleaching assay the AcEE has the highest effect with an IC 50 = 0.319 ± 0.097 mg/mL. The both extract of Artemisia campestris L. (250 mg/kg) decreased postprandial hyperglycemia in the normal and alloxane diabetic rats in a very significant manner after starch or sucrose administration as an α -amylase and α -glucosidase substrate respectively. This result is confirmed in vitro by a remarkable inhibitory effect on α -amylase digestive enzymes by an IC 50 = 1.259 ± 0.128 mg/mL and IC 50 = 0.602 ± 0.072 mg/mL receptively for AcAE and AcEE. For the α -glucosidase enzyme, the both extracts significantly inhibit α -glucosidase activity compared to the control and they are almost similar to each other. Using a jejunum perfusion technique (in situ), Artemisia campestris L. decrease the intestinal D-glucose absorption activity significantly compared to the control and comparable to the Phlorizin used as a positive control by an amount of glucose absorbed equal a 6.53 ± 0.57, 5.34 ± 0.64 and 4.71 ± 0.24 mg/10 cm/h, for AcAE, AcEE and Phlorizin respectively. CONCLUSIONS: These results showed that the Artemisia campestris L. has highest phenolic content, antioxidant activity and demonstrated a postprandial anti-hyperglycemic effect via the inhibiting of the carbohydrate digestive enzyme ( α -amylase and α -glucosidase) and the intestinal glucose absorption.

The Antispasmodic Effect of Warionia saharae Essential Oil in Experimental Models and its Mechanism of Action.

With several medicinal and aromatic species, the Asteraceae family is one of the largest angiosperm families. The genus Warionia is represented in this family by only one species, Warionia saharae. In Moroccan traditional medicine, this species is widely used to treat gastrointestinal problems. Essential oil of this plant (EoWs) was studied for possible myorelaxant and antispasmodic activities to rationalize some of the traditional uses. In this investigation, hydrodistillation was used to obtain the essential oil from the aerial part of the dry plant extract (EoWs), which was then analyzed using gas chromatography coupled to mass spectrometry (GC/MS). The major compounds identified in the EoWs are nerolidyl acetate (21.44%), ß-Eudesmol (19.47%), linalool (16.48%), 1-terpinene-4-ol (10.93%), and cineole (5.34%). EoWs is relatively safe in the case of acute intake up to 2 g/kg body weight of albino mice. The effect of EoWs on intestinal relaxation was investigated using rabbit and rat jejunal smooth muscle. We have noticed that EoWs produce a myorelaxation on basal rabbit jejunum's contractions in a concentration-dependent manner with a maximal effect at 30 µg/mL. This myorelaxation was not dependent on adrenergic receptors. When the rat jejunums were pre-contracted with 25 mM KCl or 10 µM Carbachol (CCh), EoWs had an antispasmodic action with an IC50 values of 15.76 ± 0.37 and 12.04 ± 0.30 µg/mL, respectively. Preliminary results showed that it is probable that our plant might act directly through the NO and guanylate cyclase signaling pathway and on muscarinic but not nicotinic receptors. The results reveal that the Essential oil of W. saharae appears to have an impact on intestinal relaxation in vitro conditions. This finding lends credence to the traditional usage of this plant to treat intestinal disorders.

Myorelaxant and antispasmodic effect of an aqueous extract of Artemisia campestris L. via calcium channel blocking and anticholinergic pathways.

Intestinal spasms are violent contractions that occur in the intestine, which cause discomfort to people who have them. Medicinal plants are widely used in traditional Moroccan medicine to treat these problems, among these being Artemisia campestris L. This study aims to evaluate the relaxant and antispasmodic effects of an aqueous extract of this plant (ACAE). It was performed in vitro on isolated segments of both isolated rat and rabbit jejunum mounted in an organ bath and tension recordings made via an isotonic transducer. ACAE caused a myorelaxant effect on baseline rabbit jejunum contractions in a dose-dependent and reversible manner with an IC50 of 1.52 ± 0.12 mg/ml. This extract would not act via adrenergic receptors pathway. On the other hand, the extract caused a dose-dependent relaxation of the jejunum tone in rat jejenum segments pre-contracted with either Carbachol (CCh; 10-6 M) or high K+ (KCl 75 mM) with an IC50 = 0.49 ± 0.02 mg/ml and 0.36 ± 0.02 mg/ml respectively. In the presence of different doses of the extract, the maximum response to CCh and CaCl2 was significantly reduced. This demonstrates that ACAE acts on both muscarinic receptors and voltage-dependent calcium channels. Thus, the plant extract acted on both muscarinic and nicotinic receptors and acts on the guanylate cyclase pathway, but not the nitric oxide pathway. These results indicate the mechanism by which Artemisia campestris L. acts as an effective antispasmodic agent in traditional Moroccan medicine.