Mechanisms of vasorelaxation induced by Ziziphora clinopodioides Lam. (Lamiaceae) extract in rat thoracic aorta

7-Hydroxy Frullanolide Ameliorates Isoproterenol-Induced Myocardial Injury through Modification of iNOS and Nrf2 Genes

Myocardial infarction (MI) is the principal cause of premature death. Protecting myocardium from ischemia is the main focus of intense research. 7-hydroxy frullanolide (7-HF) is a potent anti-inflammatory agent, showing its efficacy in different acute and chronic inflammatory disorders such as atherosclerosis, suggesting it can be a potential cardioprotective agent. For the induction of MI, Sprague-Dawley rats (n = 5) were administered isoproterenol (ISO) 85 mg/kg s.c at 24 h intervals for two days. The potential cardioprotective effect of 7-HF and its mechanisms were explored by in vivo and in vitro methods. 7-HF significantly prevented the extent of myocardial injury by decreasing the infarct size, preserving the histology of myocardial tissue, and reducing the release of cardiac biomarkers. Further, 7-HF increased the mRNA expression of cardioprotective gene Nrf2 and reduced the mRNA expression of iNOS. 7-HF also improved cardiac function by decreasing the cardiac workload through its negative chronotropic and negative ionotropic effect, as well as by reducing peripheral vascular resistance due to the inhibition of voltage-dependent calcium channels and the release of calcium from intracellular calcium stores. In conclusion, 7-HF showed cardioprotective effects in the MI model, which might be due to modulating the expression of iNOS and Nrf2 genes as well as improving cardiac functions.

The Anti-atherosclerosis Mechanism of Ziziphora clinopodioides Lam. Based On Network Pharmacology

We investigated the mechanisms underlying the effects of Ziziphora clinopodioides Lam. (ZCL) on atherosclerosis (AS) using network pharmacology and in vitro validation.We collected the active components of ZCL and predicted their targets in AS. We constructed the protein-protein interaction, compound-target, and target-compound-pathway networks, and performed GO and KEGG analyses. Molecular docking of the active components and key targets was constructed with Autodock and Pymol software. Validation was performed with qRT-PCR, ELISA, and Western blot.We obtained 80 components of ZCL. The network analysis identified that 14 components and 37 genes were involved in AS. Then, 10 key nodes in the PPI network were identified as the key targets of ZCL because of their importance in network topology. The binding energy of 8 components (Cynaroside, α-Spinasterol, Linarin, Kaempferide, Acacetin, Genkwanin, Chrysin, and Apiin) to 4 targets (MMP9, TP53, AKT1, SRC) was strong and <-1 kJ/mol. In addition, 13 of the 14 components were flavonoids and thus total flavonoids of Ziziphora clinopodioides Lam. (ZCF) were used for in vitro validation. We found that ZCF reduced eNOS, P22phox, gp91phox, and PCSK9 at mRNA and protein levels, as well as the levels of IL-1β, TNF-α, and IL-6 proteins in vitro (P < 0.05).We successfully predicted the active components, targets, and mechanisms of ZCL in treating AS using network pharmacology. We confirmed that ZCF may play a role in AS by modulating oxidative stress, lipid metabolism, and inflammatory response via Cynaroside, Linarin, Kaempferide, Acacetin, Genkwanin, Chrysin, and Apiin.

Chemical Profiling and Antifungal Activity of Ziziphora clinopodioides Leaf Essential Oil against the Pathogen Verticillium dahliae

Essential oils (EOs) are often used as natural antifungal agents to control the growth of phytopathogenic fungi. The aim of this study was to determine the effect of Ziziphora clinopodioides leaf EO against Verticillium dahliae, a pathogenic fungus of cotton. Gas chromatography-mass spectrometry (GC/MS) analysis revealed the presence of 15 compounds of the total of extracted oil, which was consisted of 98.79 % monoterpenes and 0.61 % sesquiterpenes. The major constituents were pulegone (62.17 %), isomenthone (18.42 %), l-menthone (5.55 %) and piperitenone (3.99 %). The mycelial growth of Verticillium dahliae was completely inhibited at 0.24 μL/mL air under vapor phase condition. Considerable morphological variations were also observed in the fungal sclerotia at the contact phase at 3 μL/mL. This study demonstrated for the first time that Z. clinopodioides EO can effectively inhibit the growth of V. dahliae, implying that it has the potential to be explored as an antifungal agent against Verticillium Wilt of cotton.

Bio-Actives from Natural Products with Potential Cardioprotective Properties: Isolation, Identification, and Pharmacological Actions of Apigenin, Quercetin, and Silibinin

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. As a result, pharmaceutical and non-pharmaceutical interventions modifying risk factors for CVDs are a top priority of scientific research. Non-pharmaceutical therapeutical approaches, including herbal supplements, have gained growing interest from researchers as part of the therapeutic strategies for primary or secondary prevention of CVDs. Several experimental studies have supported the potential effects of apigenin, quercetin, and silibinin as beneficial supplements in cohorts at risk of CVDs. Accordingly, this comprehensive review focused critically on the cardioprotective effects/mechanisms of the abovementioned three bio-active compounds from natural products. For this purpose, we have included in vitro, preclinical, and clinical studies associated with atherosclerosis and a wide variety of cardiovascular risk factors (hypertension, diabetes, dyslipidemia, obesity, cardiac injury, and metabolic syndrome). In addition, we attempted to summarize and categorize the laboratory methods for their isolation and identification from plant extracts. This review unveiled many uncertainties which are still unexplored, such as the extrapolation of experimental results to clinical practice, mainly due to the small clinical studies, heterogeneous doses, divergent constituents, and the absence of pharmacodynamic/pharmacokinetic analyses.

Investigation into the Antihypertensive Effects of Diosmetin and Its Underlying Vascular Mechanisms Using Rat Model

Objective: Diosmetin is a flavonoid that is found in many important medicinal plants that have antihypertensive therapeutic potential. Diosmetin has been shown to have antiplatelet, anti-inflammatory and antioxidant properties, which suggests that it could be a potential candidate for use in antihypertensive therapy. Methods: In vivo and in vitro methods were used for our investigation into the antihypertensive effects of diosmetin. Results: Diosmetin significantly decreased the mean arterial pressure (MAP). The effects of diosmetin on the MAP and heart rate were more pronounced in hypertensive rats. To explore the involvement of the muscarinic receptors-linked NO pathway, Nω-nitro-L-arginine methyl ester (L-NAME) and atropine were pre-administered in vivo. The pretreatment with L-NAME did not significantly change the effects of diosmetin on the MAP by excluding the involvement of NO. Unlike L-NAME, the atropine pretreatment reduced the effects of diosmetin on the MAP, which demonstrated the role of the muscarinic receptors. In the in vitro study, diosmetin at lower concentrations produced endothelium-dependent and -independent (at higher concentrations) vasorelaxation, which was attenuated significantly by the presence of atropine and indomethacin but not L-NAME. Diosmetin was also tested for high K+-induced contractions. Diosmetin induced significant relaxation (similar to verapamil), which indicated its Ca2+ antagonistic effects. This was further confirmed by diosmetin shifting the CaCl₂ CRCs toward the right due to its suppression of the maximum response. Diosmetin also suppressed phenylephrine peak formation, which indicated its antagonist effects on the release of Ca2+. Moreover, BaCl₂ significantly inhibited the effects of diosmetin, followed by 4-AP and TEA, which suggested that the K+ channels had a role as well. Conclusions: The obtained data showed the Ca2+ channel antagonism, potassium channel activation and antimuscarinic receptor-linked vasodilatory effects of diosmetin, which demonstrated its antihypertensive potential.

Exploration of Lamiaceae in Cardio Vascular Diseases and Functional Foods: Medicine as Food and Food as Medicine

In the current scenario, cardiovascular disease (CVD) is one of the most life-threatening diseases that has caused high mortality worldwide. Several scientists, researchers, and doctors are now resorting to medicinal plants and their metabolites for the treatment of different diseases, including CVD. The present review focuses on one such family of medicinal plants, called Lamiaceae, which has relieving and preventive action on CVD. Lamiaceae has a cosmopolitan distribution and has great importance in the traditional system of medicine. Lamiaceae members exhibit a wide range of activities like antioxidant, antihyperlipidemic, vasorelaxant, and thrombolytic effect, both in vitro and in vivo–these are mechanisms that contribute to different aspects of CVD including stroke, heart attack, and others. These plants harbour an array of bioactive compounds like phenolic acids, flavonoids, alkaloids, and other phytochemicals responsible for these actions. The review also highlights that these plants are a rich source of essential nutrients and minerals like omega-3 and hence, can serve as essential sources of functional foods—this can have an additional role in the prevention of CVDs. However, limitations still exist, and extensive research needs to be conducted on the Lamiaceae family in the quest to develop new and effective plant-based drugs and functional foods that can be used to treat and prevent cardiovascular diseases worldwide.

Review of Natural Resources With Vasodilation: Traditional Medicinal Plants, Natural Products, and Their Mechanism and Clinical Efficacy

For decades, chronic diseases including cardiovascular and cerebrovascular diseases (CCVDs) have plagued the world. Meanwhile, we have noticed a close association between CCVDs and vascular lesions, such as hypertension. More focus has been placed on TMPs and natural products with vasodilation and hypotension. TMPs with vasodilatory and hypotensive activities are mainly from Compositae, Lamiaceae, and Orchidaceae (such as V. amygdalina Del., T. procuinbens L., M. glomerata Spreng., K. galanga L., etc.) whereas natural products eliciting vasorelaxant potentials were primarily from flavonoids, phenolic acids and alkaloids (such as apigenin, puerarin, curcumin, sinomenine, etc.). Furthermore, the data analysis showed that the vasodilatory function of TMPs was mainly concerned with the activation of eNOS, while the natural products were primarily correlated with the blockage of calcium channel. Thus, TMPs will be used as alternative drugs and nutritional supplements, while natural products will be considered as potential therapies for CCVDs in the future. This study provides comprehensive and valuable references for the prevention and treatment of hypertension and CCVDs and sheds light on the further studies in this regard. However, since most studies are in vitro and preclinical, there is a need for more in-depth researches and clinical trials to understand the potential of these substances.

Moringa oleifera leaf extract induces vasorelaxation via endothelium-dependent hyperpolarization and calcium channel blockade in mesenteric arterial beds isolated from L-NAME hypertensive rats

BACKGROUND

An aqueous extract of Moringa oleifera leaves (MOE) is known to cause relaxation of mesenteric resistance arteries of rats in which hypertension has been induced by the administration of L-NAME, but the mechanism(s) of action of MOE remains unclear. The purpose of this study was to investigate these mechanisms in mesenteric arterial beds isolated from L-NAME induced hypertensive rats. Methods: An investigation of vascular reactivity was conducted on isolated mesenteric arterial beds by measuring the changes in perfusion pressure using an in vitro system.

RESULTS

MOE (0.001-3 mg in 0.1 ml injection volume) caused a dose-dependent relaxation in methoxamine (5 µM) pre-contracted arterial beds, which was partially abolished by endothelium removal. The endothelium-dependent component of vasorelaxation was insensitive to both L-NAME (100 µM) and indomethacin (10 µM), while completely inhibited in high KCl (45 mM)-induced contraction. MOE (1 and 3 mg/ml) showed a dose-dependent inhibitory effect on CaCl₂-induced contractions of denuded preparations in Ca²⁺-free medium containing a high KCl (60 mM) or methoxamine (10 µM). In Ca²⁺-free medium, MOE (3 mg/ml) also inhibited phenylephrine-induced contractions of denuded preparations. Conclusion: These findings suggest that MOE relaxes mesenteric arterial beds of L-NAME hypertensive rats via both endothelium-dependent and endothelium-independent mechanisms. The endothelium-dependent action occurred via endothelium-derived hyperpolarizing factor-mediated hyperpolarization. The endothelium-independent action was related to blocking the entry of extracellular Ca²⁺ via voltage-operated and receptor-operated Ca²⁺ channels, and inhibiting mobilization of sarcolemmal Ca²⁺ via inositol trisphosphate receptor Ca²⁺ channels. MOE may be potentially useful as a natural vasodilator against hypertension.

Ziziphora clinopodioides flavonoids based on network pharmacology attenuates atherosclerosis in rats induced by high-fat emulsion combined with vitamin D3 by down-regulating VEGF/AKT/NF-κB signaling pathway

Ziziphora clinopodioides flavonoids (ZCF) is a major bioactive total flavonoids compound isolated from Ziziphora clinopodioides Lam. It has been long used as an anti-atherosclerosis (AS) in clinics. However, anti-AS effects of ZCF have not been fully investigated. The objective of this study is to further investigate the anti-AS activities and mechanisms of ZCF in vivo. The main chemical components, action targets and signal pathways of Ziziphora clinopodioides Lam were predicted and analyzed by network pharmacology technology. The main bioactive components of Ziziphora clinopodioides Lam were identified using high performance liquid chromatography-mass spectrometry (HPLC-MS). In vivo experiments, atherosclerosis in rats induced by high-fat emulsion combined with vitamin D₃ and treated with simvastatin (0.45 mg/kg/d), ZCF (6.25, 12.5, 25 g/kg/d) for 7 weeks. We found that ZCF significantly reduced blood lipid levels (TG, TC, and LDL-C), and decreased lipid deposition in the aorta and atherosclerotic lesion size, inhibited mitochondrial mem- brane potential (MMP2/9/12/13) impairment. Meanwhile, ZCF may down-regulated the levels of VEGF, AKT, NF-κB, ICAM-1 and VCAM-1 proteins, indicating ZCF may play an anti-atherosclerotic role by down-regulating the VEGF/AKT/NF-κB signaling pathway. Results from this study demonstrated that ZCF have an anti-AS ability to lower lipid concentrations and protect endothelial function, antioxidant and anti-inflammatory activity, and suggested that ZCF might be a potential therapeutic drug in the prevention of AS.

A Review on the Potential Use of Medicinal Plants From Asteraceae and Lamiaceae Plant Family in Cardiovascular Diseases

Cardiovascular diseases are one of the most prevalent diseases worldwide, and its rate of mortality is rising annually. In accordance with the current condition, studies on medicinal plants upon their activity on cardiovascular diseases are often being encouraged to be used in cardiovascular disease management, due to the availability of medicinal values in certain dedicated plants. This review was conducted based on two plant families, which are Asteraceae and Lamiaceae, to study on their action in cardiovascular disease relieving activities, to review the relationship between the phytochemistry of Asteraceae and Lamiaceae families and their effect on cardiovascular diseases, and to study their toxicology. The medicinal plants from these plant family groups are collected based on their effects on the mechanisms that affect the cardiovascular-related disease which are an antioxidant activity, anti-hyperlipidemic or hypocholesterolemia, vasorelaxant effect, antithrombotic action, and diuresis effect. In reference to various studies, the journals that conducted in vivo or in vitro experiments, which were used to prove the specific mechanisms, are included in this review. This is to ensure that the scientific value and the phytochemicals of the involved plants can be seen based on their activity. As a result, various plant species from both Asteraceae and Lamiaceae plant family have been identified and collected based on their study that has proven their effectiveness and uses in cardiovascular diseases. Most of the plants have an antioxidant effect, followed by anti-hyperlipidemia, vasorelaxant, antithrombotic, and diuretic effect from the most available to least available studies, respectively. These are the mechanisms that contribute to various cardiovascular diseases, such as heart attack, stroke, coronary heart disease, and hypertension. Further studies can be conducted on these plant species by identifying their ability and capability to be developed into a new drug or to be used as a medicinal plant in treating various cardiovascular diseases.

Juglone as antihypertensive agent acts through multiple vascular mechanisms

Background: Juglone, a natural phenolic compound obtained from the walnut tree, is known for its wide range of biological activities. However, it has yet to be tested for its effects on hypertension and vascular tone. This investigation was aimed to explore the antihypertensive effect and the nature of vascular reactivity of juglone in rat models.Methods: Juglone was tested in in vivo and in vitro experiments in rats. The responses were analyzed and recorded through a PowerLab data acquisition system.Results: Intravenous injection of juglone significantly decreased the mean arterial blood pressure (MAP) in normotensive and hypertensive rats (Max. fall, 43.50 ± 2.96 vs 49.66 ± 3.28 mmHg). In rats pretreated with Nω-Nitro l-arginine methyl ester (_L-NAME), the effect of juglone on MAP was reduced as compared to the control. However, in rats pretreated with atropine the fall in MAP by juglone was not altered. Juglone induced relaxation in the phenylephrine, K⁺ (80 mM), and angiotensin II pretreated isolated rat aortic rings. This vasorelaxant effect was reduced with _L-NAME pretreatment. Atropine pretreatment did not modify the vasorelaxant effect of juglone. Pre-incubation with juglone attenuated the intracellular Ca²⁺ release by suppressing phenylephrine peak formation and also shifted CaCl₂ concentration-response curves (CRCs) to the right. Of note, combined treatment with 4-aminopyridine and barium chloride also reduced juglone-mediated vasorelaxation suggesting a role of K⁺-channels as well.Conclusion: In conclusion, juglone exerts its antihypertensive effect through vasorelaxation, which is mediated by nitric oxide, inhibition of intracellular calcium release and opening of K⁺-channels.

Schisantherin A causes endothelium-dependent and -independent vasorelaxation in isolated rat thoracic aorta

AIMS

Schisandra is a good choice in Traditional Chinese Medicine for the therapy of cardiovascular diseases, but whether it contains a or some specific component (s) responsible these effects are still unclear. In the present study, we explored whether Schisantherin A (SCA) causes vasorelaxation in isolated rat thoracic aorta.

MAIN METHODS

We selected SCA, one of the main monomers of lignans from Schisandra, to examine its vasorelaxant effect on the isolated rat thoracic aorta and also exploited several tool inhibitors to probe its underlying mechanisms.

KEY FINDINGS

SCA produced relaxation concentration-dependently on the endothelium-intact (43.56 ± 2.17%) and endothelium-denuded thoracic aorta strips (18.76 ± 3.95%) pre-contracted by phenylephrine (PE). However, after treated with indomethacin or L-NAME, SCA showed only partial vasorelaxant effects. Whereas, this vasorelaxation by SCA was not changed with specific K⁺-channel inhibitors, i.e. barium chloride (BaCl₂), 4-aminopyridine (4-AP), tetraethylamine (TEA), and glibenclamide. SCA had no effect on the aorta strips pre-contracted by PE in neither Ca²⁺-free nor CaCl₂ conditions. But, in the Ca²⁺ free and high K⁺ environment, SCA partly abolished the vasocontraction induced by CaCl₂.

SIGNIFICANCE

It was the first report to demonstrate that SCA had endothelium-dependent and -independent vasorelaxant effects on the isolated rat thoracic aorta, and the underlying mechanisms might be involved into its promoting the production of nitric oxide (NO) and prostacyclin (PGI₂), and inhibiting the voltage-dependent calcium channels (VDCCs) opening. This study may partially explain the use of Schisandra in cardiovascular diseases and facilitate further drug development as well.

Study on the Chemical Composition, Enzyme Inhibition and Antioxidant Activity of Ziziphora taurica subsp. cleonioides

Ziziphora is a plant used in Turkish and Iran traditional medicine for its antibacterial activity, sedative and stomach soothing properties. Although the chemical profile of the essential oil of different Ziziphora species is well documented, data regarding plant extracts are incomplete. In this study extracts from Ziziphora taurica subsp. cleonioides were obtained using ethyl acetate, methanol and water and the chemical profile of the aerial part of the plant was elucidated. Among the compounds identified, rosmarinic acid was the most abundant (3375.67 ± 38.02 μg/mL), at the extract of methanol, followed by chlorogenic acid (3225.10 ± 16.44). Enzyme inhibition activity against α-amylase and tyrosinase was also estimated. The ethyl acetate extract showed the highest α-amylase activity (1.95 ± 0.04 mg/mL), while the best anti-tyrosinase activity was calculated for the methanolic extract (1.25 ± 0.01 mg/mL). In addition, total phenolic, flavonoid content and antioxidant activity were evaluated. According to our results, bioactivity of the plant is of great interest, nonetheless, at the same time, it is strongly depended on the solvent used during the extraction process. Our data suggest that the plant under study may be an important source to consider against metabolic, skin pigmentation and oxidative stress related disorders.

Amelioration of allergic asthma by Ziziphora clinopodioides via upregulation of aquaporins and downregulation of IL4 and IL5

Ziziphora clinopodioides has been frequently used as an anti asthmatic plant in traditional medication. Recent work explores the anti-asthmatic activity of Z. clinopodioides in allergen-induced asthmatic mice. Intraperitoneal sensitization followed by intranasal challenge were given with ovalbumin (allergen) to develop allergic asthma. Investigational groups of animals were administered with drug methylprednisolone (MP) (15 mg/kg body weight), n-hexane fraction, ethylacetate fraction, and methanolic extract of Z. clinopodioides extract (500 mg/kg b.w.) for successive 07 days. Hematoxyline and eosin (H&E) and periodic acid-Schiff (PAS) stains were used to evaluate histopathological parameters on lung tissues. As an index of lungs tissues edema, wet/dry weight ratio of lungs was determined. Evaluation of expression levels of AQP1, AQP5, IL4, and IL5 was conducted by using RT-PCR. The data exhibited that both Z. clinopodioides and MP attenuated differential and total leukocyte counts in hematological examination i.e. in BALF and blood. Treatment with Z. clinopodioides also caused suppression of inflammatory cell infiltration and expression levels of IL4 and IL5, the later could have caused attenuation of pulmonary inflammation. The study also found decline in lung wet/dry ratio and goblet cellh hyperplasia in treated groups which indicates amelioration of lung edema. Treatment with Z. clinopodioides significantly increased the expression levels of aquaporin-1 and -5, which could have led to reduction in lung edema. The treatment with MP showed comparable results to Z. clinopodioides. Current investigation revealed that Z. clinopodioides possessed anti-asthmatic property which might be accredited to upregulagted AQP1 and AQP5 levels and downregulated IL4 and IL5 levels.

Vasorelaxant and chemical fingerprint studies of Citrus reticulatae pericarpium extracts

ETHNOPHARMACOLOGICAL RELEVANCE

Citrus reticulatae Pericarpium (Chen pi) was widely used as an important ingredient in the prescription of TCM to treat phlegm fluid retention type hypertension. Since Chen pi is involved in treatment as antihypertensive TCM formula, we have reasonable expectation in believing that it might possess vasorelaxant activity.

AIM OF THE STUDY

This study is designed to investigate the vasorelaxant effect of Chen pi and to study its pharmacology effects.

MATERIALS AND METHODS

The vasorelaxant effect of water extract of Chen pi (CRW) were evaluated on thoracic aortic rings isolated from Sprague Dawley rats. The fingerprint of Chen pi and the extracts were developed with quantification of hesperidin content by HPTLC.

RESULTS

CRW exhibited the strongest vasorelaxant activity. CRW caused the relaxation of the phenylephrine pre-contracted aortic rings in the presence and absence of endothelium as well as in potassium chloride pre-contracted endothelium-intact aortic ring. The incubation of propranolol (β-adrenergic receptor blocker), atropine (muscarinic receptor blocker), Nω-nitro-L-arginine methyl ester (NO synthase inhibitor), ODQ (sGC inhibitor), indomethacin (COX inhibitor), 4-aminopyridine (K_V blocker), barium chloride (K_ir blocker), and glibenclamide (K_ATP blocker) significantly reduced the vasorelaxant effects of CRW. CRW was also found to be active in reducing Ca²⁺ releases from the sarcoplasmic reticulum and suppressing the voltage-operated calcium channels.

CONCLUSION

The vasorelaxant effect of CRW on rat aorta involves NO/sGC, calcium and potassium channels, muscarinic and β-adrenergic receptors.

Ziziphora clinopodioides Flavonoids Protect Myocardial Cell Damage from Myocardial Ischemia-Reperfusion Injury

To investigate effects of Ziziphora clinopodioides Lam. flavonoids on ischemia-reperfusion injury of myocardial cells. After application of 6.25, 25, and 100 μg/mL Ziziphora clinopodioides Lam. flavonoids to H9C2 myocardial cells for 24H, they were treated for 4 hours with hydrogen peroxide to induce oxidative damage, whereas controls were cells without treatment and cells only incubated with hydrogen peroxide. Cell viability, lactate dehydrogenase release and mitochondrial membrane potential, intracellular Na+/K+-ATPase activity and ATP content, and reactive oxygen species formation were monitored. An ischemia-reperfusion injury rat model was established by left anterior descending coronary artery ligature in 48 Sprague-Dawley rats, which were divided into positive control with isosorbide mononitrate (10 mg/kg) injection (n=8), model (ischemia-reperfusion, n=8), sham-operated (n=8), and Ziziphora clinopodioides Lam. flavonoids low (75 mg/kg, n=8), medium (150 mg/kg, n=8), and high concentration (300 mg/kg, n=8) groups. Superoxide dismutase activity and malondialdehyde content in homogenized hearts were measured and ischemic and infarction areas were triphenyl tetrazolium chloride and H&E stained for pathological and morphological examinations. Ziziphora clinopodioides Lam. flavonoids preconditioning improved cell viability (P<0.01), intracellular Na/K ATPase activity (P<0.001), and intracellular ATP content (P<0.001) and maintained mitochondrial membrane potential (P<0.05) in hydrogen peroxide treated H9C2 cells as well as rescued superoxide dismutase activity (P<0.01), decreased the malondialdehyde content (P<0.001), and reduced myocardial damage in the ischemia-reperfusion rat model (P<0.001) compared to the controls. Ziziphora clinopodioides Lam. flavonoids may be an effective drug for protecting myocardial tissue from ischemia-reperfusion injury by reducing reactive oxygen species related damage.

Vasorelaxant effect of sinensetin via the NO/sGC/cGMP pathway and potassium and calcium channels

Orthosiphon stamineus Benth. (Lambiaceae) is an important traditional plant for the treatment of hypertension. Previous studies have demonstrated that the sinensetin content in O. stamineus is correlated with its vasorelaxant activity. However, there is still very little information regarding the vasorelaxant effect of sinensetin due to a lack of scientific studies. Therefore, the present study was designed to investigate the underlying mechanism of action of sinensetin in vasorelaxation using an in vitro precontraction aortic ring assay. The changes in the tension of the aortic ring preparations were recorded using a force-displacement transducer and the PowerLab system. The mechanisms of the vasorelaxant effect of sinensetin were determined in the presence of antagonists. Sinensetin caused relaxation of the aortic ring precontracted with PE in the presence and absence of the endothelium and with potassium chloride in endothelium-intact aortic rings. In the presence of Nω-nitro-L-arginine methyl ester (nitric oxide synthase inhibitor), methylene blue (cyclic guanosine monophosphate lowering agent), ODQ (selective soluble guanylate cyclase inhibitor), indomethacin (a nonselective cyclooxygenase inhibitor), tetraethylammonium (nonselective calcium activator K⁺ channel blocker), 4-aminopyridine (voltage-dependent K⁺ channel blocker), barium chloride (inwardly rectifying K_ir channel blocker), glibenclamide (nonspecific ATP-sensitive K⁺ channel blocker), atropine (muscarinic receptor blocker), or propranolol (β-adrenergic receptor blocker), the relaxation stimulated by sinensetin was significantly reduced. Sinensetin was also active in reducing Ca²⁺ release from the sarcoplasmic reticulum (via IP₃R) and in blocking calcium channels (VOCC). The present study demonstrates the vasorelaxant effect of sinensetin, which involves the NO/sGC/cGMP and indomethacin pathways, calcium and potassium channels, and muscarinic and beta-adrenergic receptors.

Medicinal Plants of the Family Lamiaceae in Pain Therapy: A Review

Recently, numerous side effects of synthetic drugs have lead to using medicinal plants as a reliable source of new therapy. Pain is a global public health problem with a high impact on life quality and a huge economic implication, becoming one of the most important enemies in modern medicine. The medicinal use of plants as analgesic or antinociceptive drugs in traditional therapy is estimated to be about 80% of the world population. The Lamiaceae family, one of the most important herbal families, incorporates a wide variety of plants with biological and medical applications. In this study, the analgesic activity, possible active compounds of Lamiaceae genus, and also the possible mechanism of actions of these plants are presented. The data highlighted in this review paper provide valuable scientific information for the specific implications of Lamiaceae plants in pain modulation that might be used for isolation of potentially active compounds from some of these medicinal plants in future and formulation of commercial therapeutic agents.

Vasorelaxant properties of Vernonia amygdalina ethanol extract and its possible mechanism

CONTEXT

Vernonia amygdalina Del. (VA) (Asteraceae) is commonly used to treat hypertension in Malaysia.

OBJECTIVE

This study investigates the vasorelaxant mechanism of VA ethanol extract (VAE) and analyzes its tri-step FTIR spectroscopy fingerprint.

MATERIALS AND METHODS

Dried VA leaves were extracted with ethanol through maceration and concentrated using rotary evaporator before freeze-dried. The vasorelaxant activity and the underlying mechanisms of VAE using the cumulative concentration (0.01-2.55 mg/mL at 20-min intervals) were evaluated on aortic rings isolated from Sprague Dawley rats in the presence of antagonists.

RESULTS

The tri-step FTIR spectroscopy showed that VAE contains alkaloids, flavonoids, and saponins. VAE caused the relaxation of pre-contracted aortic rings in the presence and absence of endothelium with EC₅₀ of 0.057 ± 0.006 and 0.430 ± 0.196 mg/mL, respectively. In the presence of Nω-nitro-l-arginine methyl ester (EC₅₀ 0.971 ± 0.459 mg/mL), methylene blue (EC₅₀ 1.203 ± 0.426 mg/mL), indomethacin (EC₅₀ 2.128 ± 1.218 mg/mL), atropine (EC₅₀ 0.470 ± 0.325 mg/mL), and propranolol (EC₅₀ 0.314 ± 0.032 mg/mL), relaxation stimulated by VAE was significantly reduced. VAE acted on potassium channels, with its vasorelaxation effects significantly reduced by tetraethylammonium, 4-aminopyridine, barium chloride, and glibenclamide (EC₅₀ 0.548 ± 0.184, 0.158 ± 0.012, 0.847 ± 0.342, and 0.304 ± 0.075 mg/mL, respectively). VAE was also found to be active in reducing Ca²⁺ released from the sarcoplasmic reticulum and blocking calcium channels.

CONCLUSIONS

The vasorelaxation effect of VAE involves upregulation of NO/cGMP and PGI₂ signalling pathways, and modulation of calcium/potassium channels, and muscarinic and β₂-adrenergic receptor levels.

Vasorelaxation effect of Glycyrrhizae uralensis through the endothelium-dependent Pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Glycyrrhiza uralensis (G. uralensis) is one of the herbs used in traditional Chinese medicine (TCM) and serves as an envoy medicinal. Since G. uralensis plays a major role in the anti-hypertensive TCM formulae, we believe that G. uralensis might possess vasorelaxation activity.

AIM OF THE STUDY

This study is designed to investigate the vasorelaxation effect of G. uralensis from various extracts and to study its pharmacology effect.

MATERIALS AND METHODS

The vasorelaxation effect of G. uralensis extracts were evaluated on thoracic aortic rings isolated from Sprague Dawley rats.

RESULTS

Among these three extracts of G. uralensis, 50% ethanolic extract (EFG) showed the strongest vasorelaxation activity. EFG caused the relaxation of the aortic rings pre-contracted with phenylephrine either in the presence or absence of endothelium and pre-contracted with potassium chloride in endothelium-intact aortic ring. Nω-nitro-L-arginine methyl ester, methylene blue, or 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one inhibit the vasorelaxation effect of EFG in the presence of endothelium. On the other hand, in the presence of the potassium channel blockers (tetraethylammonium and barium chloride), the vasorelaxation effect of EFG was not affected, but glibenclamide and 4-aminopyridine did inhibit the vasorelaxation effect of EFG. With indomethacin, atropine and propranolol, the vasorelaxation effect by EFG was significantly reduced. EFG was also found to be effective in reducing Ca²⁺ release from sarcoplasmic reticulum and the blocking of calcium channels.

CONCLUSIONS

The results obtained suggest that EFG is involved in the NO/sGC/cGMP pathway.

Ziziphora tenuior L. essential oil from Dana Biosphere Reserve (Southern Jordan); Chemical characterization and assessment of biological activities

ETHNOPHARMACOLOGIC RELEVANCE

Ziziphora tenuior L. (Lamiaceae) is a medicinal plant in Jordan, which is included in various antimicrobial, antiseptic, expectorant and wound healing preparations. It is used for the treatment of cough, stomach ache, dysentery, fever, uterus infection, gut inflammation and painful menstruation.

AIM OF THE STUDY

The aim of this study was to assess, for the first time, the chemical composition of the essential oil of Z. tenuior originated from southern Jordan and its antifungal effects against several yeasts. Concomitantly, the mechanisms behind the anti-fungal activity against Candida albicans were also disclosed. Since the Z. tenuior traditional uses are related with inflammatory-associated conditions, the putative anti-inflammatory activity of the oil was also unveiled. Importantly, the potential toxicity of pharmacologically active concentrations was screened in different types of mammalian cells.

MATERIALS AND METHODS

Z. tenuior essential oil, isolated by hydrodistillation, was analyzed by gas chromatography, gas chromatography-mass spectrometry and ¹³C nuclear magnetic resonance spectroscopy. Antifungal activity was evaluated against yeasts, dermatophytes and Aspergillus strains. Germ tube inhibition and biofilm formation assays were evaluated using C. albicans. Assessment of cell viability was made by the MTT assay using different types of mammalian cells, including hepatocytes, keratinocytes and macrophages. The in vitro anti-inflammatory potential of the oil was evaluated by measuring nitric oxide production using lipopolysaccharide-stimulated mouse macrophages.

RESULTS

Oxygen-containing monoterpenes are the main oil compounds: pulegone (46.8%), p-menth-3-en-8-ol (12.5%), isomenthone (6.6%) and 8-hydroxymenthone (6.2%). The highest antifungal activity was against Cryptococcus neoformans, with a MIC value of 0.16µL/mL. The oil revealed an important inhibitory effect on germ tube formation with a filamentation inhibition rate higher than 80% at 0.16µL/mL. The amount of the attached biomass was reduced. Importantly, concentrations devoid of toxicity on several mammalian cell types still displayed anti-inflammatory activity (0.16 and 0.32µL/mL).

CONCLUSIONS

These findings add significant information to the pharmacological activity of Z. tenuior, thus justifying and reinforcing the use of this plant in traditional medicine. Additionally, the antifungal and anti-inflammatory potential of the oil at non-toxic concentrations, opens new avenues for its further exploitation, for instance in health-care product development.

Vasorelaxant Action of the Chloroform Fraction of Orthosiphon stamineus via NO/cGMP Pathway, Potassium and Calcium Channels

Orthosiphon stamineus Benth. (Lamiaceae) is an important plant in traditional folk medicine that is used to treat hypertension and kidney stones. In humans, this plant has been tested as an addition regiment for antihypertensive treatment. Among the treatments for hypertension, O. stamineus had been to have diuretic and vasorelaxant effects in animal models. There is still very little information regarding the vasorelaxant effect of O. stamineus. Therefore, the present study was designed to investigate the vasorelaxant activity and mechanism of action of the fractions of O. stamineus. The vasorelaxant activity and the underlying mechanisms of the chloroform fraction of the 50% methanolic extract of O. stamineus (CF) was evaluated on thoracic aortic rings isolated from Sprague Dawley rats. CF caused relaxation of the aortic ring pre-contracted with phenylephrine in the presence and absence of endothelium, and pre-contracted with potassium chloride in endothelium-intact aortic ring. In the presence of endothelium, both indomethacin (a nonselective cyclooxygenase inhibitor) and [Formula: see text]-[1,2,4]Oxadiazolo[4,3-[Formula: see text]]quinoxalin-1-one (ODQ, selective soluble guanylate cyclase inhibitor) had a small effect on the vasorelaxation response. On the other hand, in the presence of Nω-nitro-L-arginine methyl ester (L-NAME, nitric oxide synthase inhibitor), methylene blue (cyclic guanosine monophosphate lowering agent), tetraethylammonium ([Formula: see text], nonselective calcium activator [Formula: see text] channel blocker), 4-aminopyridine (4-AP, voltage-dependent [Formula: see text] channel blocker), barium chloride ([Formula: see text], inwardly rectifying [Formula: see text] channel blocker), glibenclamide (nonspecific ATP-sensitive [Formula: see text] channel blocker), atropine (muscarinic receptor blocker) and propranolol (β-adrenergic receptor blocker), the vasorelaxant effect significantly reduced the relaxation stimulated by CF. CF was also found to be active in reducing [Formula: see text] release from the sarcoplasmic reticulum and blocking calcium channels.

Mechanism of vasorelaxation induced by eupatorin in the rats aortic ring

Previous studies demonstrated that eupatorin content in Orthosiphon stamineus fractions correlated with their vasorelaxation activity. Even with previous studies, there is still very little information on the vasorelaxation effect of eupatorin, and not many scientific studies had been carried out. Therefore, the present study was designed to investigate the vasorelaxation activity and mechanism of action of eupatorin. The vasorelaxation activity and the underlying mechanisms of eupatorin was evaluated on thoracic aortic rings isolated from Sprague Dawley rats. Eupatorin caused the relaxation of aortic rings pre-contracted with phenylephrine with and without endothelium (pD2=6.66±0.13, EMAX=99.72±6.39%; pD2=6.10±0.22, EMAX=65.78±8.01%), and also the relaxation of endothelium-intact aortic rings pre-contracted with potassium chloride (pD2=6.20±0.30, EMAX=71.89±12.25%). In the presence of Nω-nitro-l-arginine methyl ester (pD2<4.60, EMAX=24.91±6.39%), methylene blue (pD2=6.05±0.38, EMAX=66.79±9.69%), ODQ (pD25.84±0.32, EMAX=60.47±9.6%), indomethacin (pD2=6.27±0.21, EMAX=76.03±9.45%), tetraethylammonium (pD2=6.09±0.35, EMAX=69.35±11.31%), 4-aminopyridine (pD2=6.34±0.12, EMAX=76±6.1%), barium chloride (pD2=6.47±0.14, EMAX=79.61±10.02%), atropine (pD2=6.36±0.29, EMAX=86.47±12.95%) and propranolol (pD2=6.49±0.26, EMAX=83.2±12.01%), relaxation stimulated by eupatorin was significantly reduced. Eupatorin was also found to be active in reducing Ca(2+) release from sarcoplasmic reticulum and in blocking calcium channels. The present study demonstrates the vasorelaxation effect of eupatorin involving NO/sGC/cGMP and indomethacin pathways, calcium and potassium channels, and muscarinic and beta-adrenergic receptors.

Kazakh Ziziphora Species as Sources of Bioactive Substances

Ziziphora species represent the prototypical example of the Lamiaceae family. The phytochemicals present in Ziziphora include monoterpenic essential oils, triterpenes and phenolic substances belonging to the flavonoids. In Kazakh traditional medicine, Ziziphora species possess several medicinal uses. In particular, Z. bungeana Lam. and Z. clinopodioides Lam. are used for the treatment of illnesses related to the cardiovascular system or to combat different infections. Unfortunately, the majority of the information about the complex Ziziphora species is only available in Russian and Chinese language, therefore, we decided gather all available information on Kazakhstan Ziziphora, namely its content compounds, medicinal uses and published patents, to draw the attention of scientists to this very interesting plant with high medicinal potential.

Overview of Antagonists Used for Determining the Mechanisms of Action Employed by Potential Vasodilators with Their Suggested Signaling Pathways

This paper is a review on the types of antagonists and the signaling mechanism pathways that have been used to determine the mechanisms of action employed for vasodilation by test compounds. Thus, we exhaustively reviewed and analyzed reports related to this topic published in PubMed between the years of 2010 till 2015. The aim of this paperis to suggest the most appropriate type of antagonists that correspond to receptors that would be involved during the mechanistic studies, as well as the latest signaling pathways trends that are being studied in order to determine the route(s) that atest compound employs for inducing vasodilation. The methods to perform the mechanism studies were included. Fundamentally, the affinity, specificity and selectivity of the antagonists to their receptors or enzymes were clearly elaborated as well as the solubility and reversibility. All the signaling pathways on the mechanisms of action involved in the vascular tone regulation have been well described in previous review articles. However, the most appropriate antagonists that should be utilized have never been suggested and elaborated before, hence the reason for this review.

Mechanisms underlying vasorelaxation induced in rat aorta by galetin 3,6-dimethyl ether, a flavonoid from Piptadenia stipulacea (Benth.) Ducke

In this study, we investigated the relaxant action of galetin 3,6-dimethyl ether (FGAL) on rat aorta. The flavonoid relaxed both PMA‑ and phenylephrine (Phe)-induced contractions (pD₂ = 5.36 ± 0.11 and 4.17 ± 0.10, respectively), suggesting the involvement of PKC and Phe pathways or α₁ adrenergic receptor blockade. FGAL inhibited and rightward shifted Phe-induced cumulative concentration‑response curves, indicating a noncompetitive antagonism of α₁ adrenergic receptors. The flavonoid was more potent in relaxing 30 mM KCl- than 80 mM KCl-induced contractions (pD₂ = 5.50 ± 0.22 and 4.37 ± 0.12). The vasorelaxant potency of FGAL on Phe-induced contraction was reduced in the presence of 10 mM TEA⁺. Furthermore, in the presence of apamin, glibenclamide, BaCl₂ or 4-AP, FGAL-induced relaxation was attenuated, indicating the participation of small conductance calcium-activated K⁺ channels (SK_Ca), ATP-sensitive K⁺ channels (K_ATP), inward rectifier K⁺ channels (K_ir) and voltage-dependent K⁺ channels (K_V), respectively. FGAL inhibited and rightward shifted CaCl₂-induced cumulative concentration-response curves in both depolarizing medium (high K⁺) and in the presence of verapamil and phenylephrine, suggesting inhibition of Ca²⁺ influx through voltage-gated calcium channels (Ca_V) and receptor operated channels (ROCs), respectively. Likewise, FGAL inhibited Phe-induced contractions in Ca²⁺-free medium, indicating inhibition of Ca²⁺ release from the sarcoplasmic reticulum (SR). FGAL potentiated the relaxant effect of aminophylline and sildenafil but not milrinone, suggesting the involvement of phosphodiesterase V (PDE V). Thus, the FGAL vasorelaxant mechanism involves noncompetitive antagonism of α₁ adrenergic receptors, the non-selective opening of K⁺ channels, inhibition of Ca²⁺ influx through Ca_V or ROCs and the inhibition of intracellular Ca²⁺ release. Additionally, there is the involvement of cyclic nucleotide pathway, particularly through PDE V inhibition.

Development of a rapid resolution liquid chromatography-diode array detector method for the determination of three compounds in Ziziphora clinopodioides Lam from different origins of Xinjiang

CONTEXT

As a traditional Uygur medicinal plant, Z. clinopodioides Lam has various uses in Xinjiang.

AIMS

A reversed-phase rapid resolution liquid chromatography (RP-RRLC) method with diode array detector (DAD) was developed for simultaneous determination of diosmin, linarin, and pulegone from Ziziphora clinopodioides Lam, a widely used in traditional Uygur medicine for treating heart disease, high blood pressure, and other diseases.

SETTINGS AND DESIGN

Compounds were separated on a XDB-C18 reversed-phase analytical column (50 mm × 4.6 mm, 1.8 μm) with gradient elution using methanol and 1% aqueous acetic acid (v/v) at 0.9 mL/min. he detection wavelength was set at 270 nm.

MATERIALS AND METHODS

Ziziphora clinopodioides Lam. were collected from ten different origins in Xinjiang, including the Ban fang ditch, Tuoli, the Altay mountains, Terks, Xiata Road, Zhaosu Highway, Guozigou, Fukang, Jimsar, Wulabo.

STATISTICAL ANALYSIS USED

The intra-day and inter-day precisions of all three compounds were less than 0.89% and the average recoveries ranged from 97.4 to 104.1%. There were highly significant linear correlations between component concentrations and specific chromatographic peak areas (R2 > 0.999).

RESULTS

The proposed method was successfully applied to determine the levels of three active components in Z. clinopodioides Lam. samples from different locations in Xinjiang.

CONCLUSIONS

The proposed method is simple, consistent, accurate, and could be utilized as a quality control method for Z. clinopodioides Lam.

Chemical Fingerprinting by RP-RRLC-DAD and Principal Component Analysis of Ziziphora clinopodioides from Different Locations

An efficient and accurate fingerprinting method using reversed-phase rapid-resolution liquid-chromatography coupled with photodiode array detection has been developed and optimized to examine the variance in active compounds among Ziziphora clinopodioides Lam from different locations. Three active components, diosmin, linarin and pulegone, were identified by matching their retention times and UV spectra with the corresponding reference compounds. Our results indicated that chromatographic fingerprints, in combination with principal component analysis (PCA) and hierarchical clustering analysis (HCA), could efficiently identify and distinguish Z. clinopodioides from different sources. Our fingerprinting methods and data will be useful for quality control, and thus, more effective dosing in clinical application of Z. clinopodioides.