The relaxant and contractile effects of Verbascum speciosum extracts on rat trachea: phenolic and organic acid contents and acetylcholinesterase inhibition

Year 2026, Volume: 73 Issue: 1, 13 - 21, 01.01.2026

Adem Teke , Ebru Yıldırım , Ender Yarsan

https://doi.org/10.33988/auvfd.1667820

Abstract

Verbascum speciosum is traditionally used against respiratory system diseases such as asthma and bronchitis. This study investigated the effects of extracts prepared from V. speciosum Schrad. on isolated rat trachea. Plants collected in July 2023 were used to prepare flower methanol extract (FME), leaf methanol extract (LME), flower water extract (FWE), and leaf water extract (LWE). Phenolic and organic acid contents and acetylcholinesterase (AChE) inhibitory activity were measured. Methanol extracts had a more concentrated phenolic content. The IC50 values for AChE inhibition were higher in the methanol extracts. The extracts were directly tested on isolated rat trachea. LME did not produce contractile or relaxant responses. However, FME, FWE, and LWE elicited contractile responses in a dose- and extract-dependent manner. All extracts relaxed rat trachea pre-contracted with KCl and carbachol (CCh) in a dose- and extract-dependent manner. For trachea pre-contracted with ACh, LWE and FWE induced contraction, while LME and FME caused relaxation. LME exhibited the strongest relaxant effect at 100 mg, relaxing KCl-induced contraction by 103.81±7.94%, CCh-induced contraction by 109.21±2.64%, and ACh-induced contraction by 111.45±5.95%. The findings suggest that V. speciosum may contain various pharmacologically active compounds useful for treating respiratory diseases. However, the contractile response of water extracts to ACh-induced contraction may indicate potential risks of consuming Verbascum-containing herbal teas.

Keywords

airway smooth muscle , isolated organ bath , rat trachea , Verbascum , Verbascum speciosum Schrad.

Project Number

2023/078

References

• Aksoy A, Altunatmaz SS, Aksu F, et al (2024): Bee bread as a functional product: phenolic compounds, amino acid, sugar, and organic acid profiles. Foods, 13, 795.
• Alan Y, Almaz Z (2022): Investigation of anticholinesterase and anticancer effects of Verbascum insulare Boiss. Et Heldr. extracts growing in Mus region. Bitlis Eren Univ J Sci, 11, 744-750.
• Ali N, Ali Shah SW, Shah I, et al (2012): Anthelmintic and relaxant activities of Verbascum thapsus Mullein. BMC Complement Altern Med, 12, 1-7.
• Alipieva KI, Orhan İE, Çankaya İİT, et al (2014): Treasure from garden: chemical profiling, pharmacology and biotechnology of mulleins. Phytochem Rev, 13, 417-444.
• Alkowni R, Jaradat N, Fares S (2023): Total phenol, flavonoids, and tannin contents, antimicrobial, antioxidant, vital digestion enzymes inhibitory and cytotoxic activities of Verbascum fruticulosum. EuJIM, 60, 102256.
• Amini S, Hassani A, Alirezalu A, et al (2022): Phenolic and flavonoid compounds and antioxidant activity in flowers of nine endemic Verbascum species from Iran. J Sci Food Agric, 102, 3250-3258.
• Angeloni S, Zengin G, Sinan KI, et al (2021): An insight into Verbascum bombyciferum extracts: different extraction methodologies, biological abilities and chemical profiles. Ind Crops Prod, 161, 1-10.
• Boğa M, Ertaş A, Haşimi N, et al (2016): Phenolic profile, fatty acid and essential oil composition analysis and antioxidant, antialzheimer and antibacterial activities of Verbascum flavidum extracts. Chiang Mai J Sci, 43, 1090-1101.
• Bozkurt TE, Tatlı İİ, Kahraman C, et al (2014): Inhibitory effect of the methanolic extract of Verbascum latisepalum Hub.-Mor. on endothelium-dependent relaxation in rat thoracic aorta. ZNC, 69, 219–225.
• Bozkurt İ, Sabancılar İ, Kılıç Ö, et al (2024): The effects of Lamium garganicum L. Subsp. lasioclades (Stapf.) R. Mill plant against fibroblast (U2OS cell), acetylcholinesterase, glutathione S‐transferase: An in vitro, in silico biological activity screening study. Chem Biodivers, e202402421, 1-25.
• Chou YL, Wu CC, Wang HW (2010): Effects of bambuterol and terbutaline on isolated rat’s tracheal smooth muscle. Eur Arch Otorhinolaryngol, 267, 1305-1311.
• Flores-Flores A, Hidalgo-Figueroa S, Villalobos-Molina R, et al (2018): Relaxant effect of structurally related flavonoids on isolated tracheal rat rings: A SAR study. Med Chem Res, 27, 122-127.
• Fu Y, Wang P, Zhou W, et al (2021): Verbascum chinense L. leaf aqueous extract green-synthesized nanoparticles: Its performance in the treatment of several types of human lung cancers. AJC, 14, 103413.
• Georgiev M, Alipieva K, Orhan İ, et al (2011): Antioxidant and cholinesterases inhibitory activities of Verbascum xanthophoeniceum Griseb. and its phenylethanoid glycosides. Food Chem, 128, 100-105.
• Geyesa JM, Esho TB, Legesse BA, et al (2024): Antibacterial and antioxidant potential analysis of Verbascum sinaiticum leaf extract and its synthesized silver nanoparticles. Heliyon, 10, e24215.
• Grigorov M, Pavlović D, Tadić V, et al (2022): Chemical composition of the ethanol extracts of Verbascum niveum flowers and leaves. Maced Pharm Bull, 68, 381-382.
• Görhan KÖ, Öztürk F (2021): Ethnopharmacological survey of medicinal and foods plants in Derecik (Hakkari-Turkey). Indian J Tradit Knowl, 20, 416-425.
• Güven L, Behbudbayli U, Ertürk A, et al (2023): Determination of antioxidant, antimicrobial, anticholinesterase, antityrosinase, antidiabetic and antiglaucoma activities of essential oils from three different Thymus species and their chemical characterization by GC-MS analysis. J Essent Oil Bear Plants, 26, 1424-1446.
• Hasan N, Laskar RA, Farooqui SA, et al (2024): Genetic improvement of medicinal and aromatic plant species: breeding techniques, conservative practices and future prospects. Crop Des, 3, 1-17.
• Hazman Ö, Khamidov G, Yilmaz MA, et al (2024): Green synthesis of Ag nanoparticles from Verbascum insulare Boiss. and Heldr.: Evaluation of antimicrobial, anticancer, antioxidant properties and photocatalytic degradation of MB. J PhotoChem Photobiol A Chem, 453, 115601.
• Kayır S, Demirci Y, Demirci S, et al (2018): The in vivo effects of Verbascum speciosum on wound healing. S Afr J Bot, 119, 226-229.
• Kızıltaş H, Bingöl Z, Gören AC, et al (2023): Analysis of phenolic compounds by LC-HRMS and determination of antioxidant and enzyme inhibitory properties of Verbascum speciosum Schrad. Rec Nat Prod, 17, 485-500.
• Okasha YM, Fathy FI, Soliman FM, et al (2023): The untargeted phytochemical profile of Verbascum thapsus L. with potent antiviral, antibacterial and anticancer activities. S Afr J Bot, 156, 334–341.
• Özüdoğru B, Akaydın G, Erik S, et al (2011): Inferences from an ethnobotanical field expedition in the selected locations of Sivas and Yozgat provinces (Turkey). J Ethnopharmacol, 137, 85-98.
• Selseleh M, Ebrahimi SN, Aliahmadi A, et al (2020): Metabolic profiling, antioxidant, and antibacterial activity of some Iranian Verbascum L. species. Ind. Crops Prod, 153, 112609.
• Uçar Türker A, Camper ND (2002): Biological activity of common mullein, a medicinal plant. J Ethnopharmacol, 82, 117-125.
• Yıldırım E (2005): The investigation of the effect of levamisole on rabbit trachea alone and combined with trichlorfon. Ankara Univ Vet Fak Derg, 52, 23-28.
• Zengin G, Mahomoodally MF, Sinan KI, et al (2021): Evaluation of chemical constituents and biological properties of two endemic Verbascum species. Process Biochem, 108, 110–120.