Compositional analysis and in vivo anti-diabetic activity of wild Algerian Marrubium vulgare L. infusion

Vasorelaxant effects of biochemical constituents of various medicinal plants and their benefits in diabetes

Endothelial function plays a pivotal role in cardiovascular health, and dysfunction in this context diminishes vasorelaxation concomitant with endothelial activity. The nitric oxide-cyclic guanosine monophosphate pathway, prostacyclin-cyclic adenosine monophosphate pathway, inhibition of phosphodiesterase, and the opening of potassium channels, coupled with the reduction of calcium levels in the cell, constitute critical mechanisms governing vasorelaxation. Cardiovascular disease stands as a significant contributor to morbidity and mortality among individuals with diabetes, with adults afflicted by diabetes exhibiting a heightened cardiovascular risk compared to their non-diabetic counterparts. A plethora of medicinal plants, characterized by potent pharmacological effects and minimal side effects, holds promise in addressing these concerns. In this review, we delineate various medicinal plants and their respective biochemical constituents, showcasing concurrent vasorelaxant and anti-diabetic activities.

Neuroprotective Effect of Marrubium vulgare Extract in Scopolamine-Induced Cognitive Impairment in Rats: Behavioral and Biochemical Approaches

The potential of Marrubium vulgare to alleviate scopolamine (Sco)-induced deficits in spatial working memory has drawn considerable scientific interest. This effect is partly attributed to its potent antioxidant and acetylcholinesterase inhibitory (AChEI) activities. This study examined the effects of M. vulgare extract, standardized to marrubiin content, on recognition memory in healthy and Sco-treated rats. Male Wistar rats (200-250 g) were divided into four groups. The extract was orally administered for 21 days and Sco (2 mg/kg) was intraperitoneally injected for 11 consecutive days. Memory performance was assessed using the novel object recognition test. Levels of acetylcholine (ACh), noradrenaline (NA), serotonin (Sero), and brain-derived neurotrophic factor (BDNF) and the phosphorylation of cAMP response element-binding protein (p-CREB) were evaluated in the cortex and hippocampus via ELISA. BDNF and CREB expression levels were assessed using RT-PCR. The results showed that M. vulgare significantly alleviated Sco-induced memory impairment, preserved cholinergic function in the hippocampus, increased NA levels in the brain, and restored pCREB expression in the cortex following Sco-induced reduction. In healthy rats, the extract upregulated BDNF, pCREB, and Bcl2 expression. Our findings indicate that the neuroprotective effects of M. vulgare may be linked to the modulation of cholinergic function, regulation of NA neurotransmission, and influence on key memory-related molecules.

Development of Biologically Active Phytosynthesized Silver Nanoparticles Using Marrubium vulgare L. Extracts: Applications and Cytotoxicity Studies

Metal nanoparticle phytosynthesis has become, in recent decades, one of the most promising alternatives for the development of nanomaterials using "green chemistry" methods. The present work describes, for the first time in the literature, the phytosynthesis of silver nanoparticles (AgNPs) using extracts obtained by two methods using the aerial parts of Marrubium vulgare L. The extracts (obtained by classical temperature extraction and microwave-assisted extraction) were characterized in terms of total phenolics content and by HPLC analysis, while the phytosynthesis process was confirmed using X-ray diffraction and transmission electron microscopy, the results suggesting that the classical method led to the obtaining of smaller-dimension AgNPs (average diameter under 15 nm by TEM). In terms of biological properties, the study confirmed that AgNPs as well as the M. vulgare crude extracts reduced the viability of human gingival fibroblasts in a concentration- and time-dependent manner, with microwave-assisted extracts having the more pronounced effects. Additionally, the study unveiled that AgNPs transiently increased nitric oxide levels which then decreased over time, thus offering valuable insights into their potential therapeutic use and safety profile.

Chemical Investigation and Antinociceptive Activity Evaluation of Marrubium Vulgare L. Aqueous Extract

Marrubium vulgare L. (Lamiaceae) has a long history of use in traditional herbal medicine for the treatment of respiratory tract infections, inflammatory conditions, and pain. This study aimed to investigate the chemical composition, acute toxicity, and antinociceptive effects of the aqueous extract from M. vulgare leaves (AEMV). Antioxidant activity was evaluated using DPPH and reducing power assays. The chemical composition of AEMV was determined through LC-MS/MS, and the levels of total phenolics, flavonoids, and condensed tannins were quantified. Acute oral toxicity was assessed in male Swiss mice with a single oral dose of AEMV (1, 2, 5 g/kg). The analgesic impact was examined through writhing, hot plate, and formalin tests. Our findings not only confirmed the safety of the extract in animal models but also revealed significant antioxidant activity in AEMV. High-performance liquid chromatography (HPLC) analysis identified important bioactive compounds, with marrubiin being a major component. Furthermore, AEMV demonstrated robust antinociceptive properties in all conducted tests, highlighting its potential as a valuable natural source of bioactive compounds suitable for a wide range of therapeutic applications.

Marrubium vulgare Extract Improves Spatial Working Memory and Oxidative Stress Damage in Scopolamine-Treated Rats

Background

The cholinergic neuronal loss in the basal forebrain and increasing brain oxidative stress are one of the main features of the brain suffering from Alzheimer's disease. Marrubium vulgare (M. vulgare), commonly known as 'white horehound,' possesses a variety of valuable properties, such as antioxidative, anti-inflammatory, and antidiabetic activities. Moreover, it possesses neuromodulatory properties that could potentially impact short-term memory functions.

Objective

The present study was undertaken to investigate the preventive effects of water M. vulgare extract on working memory, cholinergic neurotransmission, and oxidative stress in rats with scopolamine (Sco)-induced dementia.

Methods

Male Wistar rats (200-250 g) were divided into four experimental groups. The plant extract was administered orally for 21 days, and Sco (2 mg/kg) was administered intraperitoneally for 11 consecutive days. The behavioral performance of the animals was evaluated by the T-maze test. The effect of the extract on acetylcholinesterase (AChE) activity and antioxidant status in cortex and hippocampus were also monitored.

Results

Our experimental data revealed that treatment with M. vulgare significantly increased the percentage of correct choices of rats with Sco-induced dementia in the T maze test (by 38%, p < 0.05). Additionally, it reduced AChE activity in the hippocampus (by 20%, p < 0.05) and alleviated oxidative stress induced by Sco, particularly in the cortex.

Conclusions

M. vulgare water extract demonstrated working memory preserving effect in rats with Sco-induced dementia, AChE inhibitory activity and in vivo antioxidant potential, and deserve further attention.

Ultrasound-Assisted Extraction of Verbascoside from Clerodendrum glandulosum Leaves for Analysis of Antioxidant and Antidiabetic Activities

Verbascoside (VER) is a phenylethanoid glycoside compound found in Clerodendrum species and is an important part of traditional medicine. It is found in the leaves of Clerodendrum glandulosum, which is taken as a soup or vegetable and also utilized in traditional medicine by the people of Northeast India, especially against hypertension and diabetes. In the present study, VER was extracted from C. glandulosum leaves using ultrasound-assisted extraction through the solvent extraction method (ethanol-water, ethanol, and water). The ethanol extract had the highest phenolic and flavonoid contents, viz., 110.55 mg GAE/g and 87.60 mg QE/g, respectively. HPLC and LC-MS were used to identify the active phenolic compound, and VER was found to be the main component present in the extraction with a molecular weight of 624.59 g/mol. NMR (¹H, 2D-COSY) analysis showed the presence of hydroxytyrosol, caffeic acid, glucose, and rhamnose in the VER backbone. Further, different antioxidant activities and antidiabetic and antihyperlipidemia enzyme markers' inhibition against VER-enriched ethanol extract were evaluated. The results showed that ultrasound extraction of polyphenols using ethanol from C. glandulosum could be a promising technique for the extraction of bioactive compounds.

Inhibition of α-Glycosidase by Lippia dulcis Trevir. (Verbenaceae) Preparations, Quantification of Verbascoside, and Study of Its Molecular Docking

This study aimed to quantify verbascoside (VEB), perform molecular docking studies of VEB with the α-glucosidase (GL) of Bacillus stearothermophilus, and evaluate the inhibition of the enzyme by L. dulcis preparations. The substrate concentration and presence of reduced glutathione were evaluated for their effect on the in vitro inhibition of the GL enzyme. Assays were also performed in the presence and absence of simulated gastric fluid. The antidiabetic fractions 2 and 3 were the most inhibited GL, but their activity were significantly decreased in the presence of gastric fluid. Chromatographic analyses confirmed the predominant presence of VEB in the samples. The samples had VEB concentrations between 49.9 and 243.5 mg/g. Simulation of the molecular docking of VEB were consistent with its GL-inhibitory activity. It can conclude that the crude ethanol extract and fractions show inhibitory activity against the GL enzyme.

Effects of preharvest factors on antidiabetic potential of some foods and herbal plants

Diabetes is a metabolic disorder with no definite treatment, but it can be controlled by changing lifestyle and diet. Consumption of high-fiber and nutrient-rich foods including vegetables have been shown to reduce risks of obesity and Type II Diabetes Mellitus (T2DM). Also, many herbal plants have been associated with reduced risks of T2DM because of their composition of secondary metabolites. Antioxidant activities of some secondary metabolites have potent inhibitory effects against inflammation linked with insulin resistance and oxidative stress. More than 800 known medicinal plants are used to control diabetes and its relevant complications. However, variations in preharvest factors including plant genotype, growing medium properties, climatic factors, and management practices can influence plant growth and their accumulation of phytochemicals with health-promoting properties. However, the effects of these preharvest factors on the antidiabetic properties of plant secondary metabolites are neither explicit nor easily accessible in the literature. Therefore, this review aims to document recent studies that reported on under-exploited medicinal plants with antidiabetic properties. We reviewed several important preharvest factors that can potentially affect the synthesis of phytoconstituents which possess antidiabetic properties. This review will help identify gaps for future research in phytomedicine and functional foods.

The Role of Ingenane Diterpenes in Cancer Therapy: From Bioactive Secondary Compounds to Small Molecules

Diterpenes are a class of critical taxonomic markers of the Euphorbiaceae family, representing small compounds (eg, molecules) with a wide range of biological activities and multi-target therapeutic potential. Diterpenes can exert different activities, including antitumor and multi-drug resistance-reversing activities, and antiviral, immunomodulatory, and anti-inflammatory effects, mainly due to their great structural diversity. In particular, one polycyclic skeleton has been highlighted: ingenane. Besides this natural diterpene, promising polycyclic skeletons may be submitted to chemical modification—by in silico approaches, chemical reactions, or biotransformation—putatively providing more active analogs (eg, ingenol derivatives), which are currently under pre-clinical investigation. This review outlines the current mechanisms of action and potential therapeutic implications of ingenol diterpenes as small cancer molecules.

Tunisian Horehound (Marrubium vulgare) Aqueous Extract Improves Treatment of Bleomycin-Induced Lung Fibrosis in Rat

Pulmonary fibrosis (PF) remains one of the most serious pneumopathies whose diagnosis and physiopathogenesis are still poorly understood and no treatment has been shown to be effective. Recently, many studies have shown a renewed interest in plants thanks to their pharmacological potentials, like horehound, known, for its anti-inflammatory and antioxidant activities. The present study investigated the effects of the aqueous extract of horehound (Mae) on bleomycin (BLM)-induced PF in rats. Thirty rats were divided into three groups. The control group received no treatment, the BLM group received only intratracheally BLM (2 mg/kg), and the Mae group underwent administration of BLM+ Mae (2 mL/kg) daily for 20 days. Obtained results showed that Mae, rich in polyphenols, could significantly improve the damage caused by BLM by reducing the inflammatory index and the fibrosis score, bringing the lung structure of fibrotic rats close to that of control rats. As well, Mae obviously acted on the BLM inflammatory reaction, and the counting of bronchoalveolar lavage fluid (Balf) cells showed an increase in total cell number and a decrease in the infiltration of inflammatory cells in the bronchoalveolar space. In addition, the BLM instillation was accompanied by oxidative stress in the lung, liver, and kidney tissues, proven by an increase in lipid peroxidation, as well as through depletion of superoxide dismutase (SOD) and catalase (CAT). The Mae treatment reversed all disturbances of BLM-induced oxidative stress parameters promoting antioxidant and anti-inflammatory of the latter. These findings point to Mae as a promising candidate for the treatment of pulmonary fibrosis.

Neurobehavioral and Biochemical Evidences in Support of Protective Effect of Marrubiin (Furan Labdane Diterpene) from Marrubium vulgare Linn. and Its Extracts after Traumatic Brain Injury in Experimental Mice

Traumatic brain injuries due to sudden accidents cause major physical and mental health problems and are one of the main reasons behind the mortality and disability of patients. Research on alternate natural sources could be a boon for the rehabilitation of poor TBI patients. The literature indicates the Marrubium vulgare Linn. and its secondary metabolite marrubiin (furan labdane diterpene) possess various pharmacological properties such as vasorelaxant, calcium channel blocker, antioxidant, and antiedematogenic activities. Hence, in the present research, both marrubiin and hydroalcoholic extracts of the plant were evaluated for their neuroprotective effect after TBI. The neurological severity score and oxidative stress parameters are significantly altered by the test samples. Moreover, the neurotransmitter analysis indicated a significant change in GABA and glutamate. The histopathological study also supported the observed results. The improved neuroprotective potential of the extract could be attributed to the presence of a large number of secondary metabolites including marrubiin.

Variation of the Chemical Composition of Essential Oils and Total Phenols Content in Natural Populations of Marrubium vulgare L

Marrubium vulgare is a valuable source of natural bioactive molecules with high preventive and therapeutic effectiveness. Therefore, this study aimed to study the chemical polymorphism of natural populations of M. vulgare in Tunisia by quantitative chemical markers and the estimation of divergence between populations. Phytochemical analyses of the eight natural populations of Tunisian Marrubium vulgare prospected in different bioclimatic stages, revealed 42 compounds of essential oils representing 96.08% to 100% of the total oil. Hydrocarbon sesquiterpenes were the main fraction of all the populations studied and β-bisabolene was the major compound (from 30.11% to 71.35% of the total oil). The phytochemical investigation of the M. vulgare plant indicated the presence of essential oil with significant percentages of phenolic compounds. A significant quantitative and qualitative variation in the essential oils is detected for both major and minor compounds. The principal components analysis (PCA) performed in the single and combined traits provides a good distinction among populations, not according to their geographical and/or bioclimatic origins. Moreover, the phytochemical analysis of the leaves showed that the Tunisian populations, i.e., the populations of Kasserine, Kef, and Beja, were very rich in phenolic compounds (from 20.8 to 44.65 mg GAE/g DW). Flavonoids compounds were also the main class of total polyphenols present in all the tested populations (from 8.91 to 37.48 mg RE/g DW). The quantitative genetic diversity estimated by the population's structure, based on PCA analysis, was an adaptation to the changes in the environmental conditions. Overall, our study indicated that natural populations of M. vulgare had different chemotypes of essential oils and they were rich in phenolic compounds, particularly flavonoids, which opens a new prospect for industrial use and differential exploitation of this species.

HPLC-Analysis, Biological Activities and Characterization of Action Mode of Saudi Marrubium vulgare against Foodborne Diseases Bacteria

The present study aims to evaluate the chemical composition, metabolites secondary and pharmacology activities of methanolic extract of Marrubium vulgare collected from King Saudi Arabia. Moreover, the primary mode of action of the tested extract was studied here for the first time against E. coli and L. monocytogenes. HPLC analysis shows that the major components in the tested extract are luteolin-7-O-d-glucoside, ferulic acid and premarrubiin. Obtained data demonstrated that the investigated extract was richer in phenol (26.8 ± 0.01 mg/GAE g) than in flavonoids (0.61 ± 0.05 mg EC/mL). In addition, the methanolic extract showed an important antioxidant capacity against the DPPH (IC₅₀ = 35 ± 0.01 µg/mL) and ABTS (IC₅₀ = 25 ± 0.2 µg/mL) radical scavenging and a strong inhibition of acetylcholinesterase enzyme with an IC₅₀ value corresponding to 0.4 mg/mL. The antibacterial activity demonstrated that the evaluated extract had significant activity against both Gram-positive and Gram-negative bacteria. The effect of time on cell integrity on E. coli and L. monocytogenes determined by time-kill and bacteriolysis tests showed that the M. vulgare extract reduced the viability of both strains after 8 and 10 h and had a bacteriolytic effect against two different categories of bacteria, Gram-positive and negative, which are not of the same potency. Based on obtained data, it can be concluded that Saudi M. vulgare has a high pharmacological importance and can be used in preparation of food or drugs.

Ethnobotanical Survey of Medicinal Plants Used by Traditional Healers to Treat Diabetes in the Taza Region of Morocco

Type 2 diabetes is one of the noncommunicable diseases that is becoming a pandemic in Africa. In Morocco, traditional healers have started to use herbal medicines for the treatment of diabetes either individually or in combination with food. The current study aimed to perform an ethnobiological survey of antidiabetic plants use in the Taza region of Morocco. A total of 193 traditional healers were interviewed using a semistructured questionnaire. Data collected were analyzed utilizing the use value (UV), fidelity level (FL), and relative frequency citation (RFC) indices. Forty-six plant species belonging to 28 families were recorded for the treatment of diabetes in the Taza region of Morocco. The most frequently cited plant species are Salvia officinalis, Marrubium vulgare, and Ajuga iva. Lamiaceae, Asteraceae, and Fabaceae were the most reported families. Leaves are the most used part of plants to prepare drugs, the decoction is the preferred mode of preparation, and remedies are often administered orally. Interestingly, Cytisus battandieri, Urginea maritima, Plantago ovata, and Ziziphus jujuba were reported as new medicinal plants used to treat diabetes in the Taza region of Morocco. People in the Taza region still rely on indigenous plants for their basic healthcare needs. Further research should be carried out to validate the antidiabetic effect of the newly reported plant species. This validation can be investigated by the determination of bioactive compounds and evaluation of their in vitro and in vivo antidiabetic effects.

An overview on ethnobotanico-pharmacological studies carried out in Morocco, from 1991 to 2015: Systematic review (part 1)

ETHNOPHARMACOLOGICAL RELEVANCE

The full bibliometric records of data retrieved from ethnobotanical field studies carried out in Morocco (1991-2015) was quali-quantitatively analysed. Despite the importance of traditional medicinal uses in Morocco, any comments about the methodologies and approaches adopted by reviewed studies have been undertaken. Include more data about the importance of traditional medicinal uses in Morocco.

AIM OF THE STUDY

Three key points were targeted in this review: (i) to contribute to original compilation of medicinal plants traditionally used by people at whole Morocco, by gathering and documenting the current status of these ancestral medical practices, (ii) to provide a novel insight into the relationship between local and biomedical disease concepts in Moroccan society, taking into account health-related beliefs, and their influences on medicinal plant uses, (iii) to figurout the weaknesses and the strengths of the conceptual approches and methods adopted by researchers in ethnobotanical field works.

MATERIALS AND METHODS

With the help of a computerized database querying, we conducted an extensive literature search respecting our integration criteria. We performed this bibliographic research by using the following search engines available over the Web: Google Scholar, PUBMED, Sciencedirect, Current Content Connect, SCOPUS, SPRINGER LINK, GLOBAL PLANTS, Cochrane Library and SCIRUS. The scientific names listed in the present paper have been validated according to the "The Plant List" and the African Plants Database in order to standardize ethnobotanical data on an international level. For the analysis of data gathered, quali-quantitative analyses have been performed.

RESULTS

A total of 905 medicinal plant species belonging to 116 families and 726 genera have been selected from 63 published articles. The dominant families were ASTERACEAE (111 species) followed by the FABACEAE (77 species), LAMIACEAE (75 species) and APIACEAE (46 species). The plant species listed are used to cure several public ailments. The digestive ailments represented the most important category (494 species) followed by dermatological diseases (407 species), diabetes (315 species) and urinary diseases (277 species). We assigned the importance of the plant species by several measures (including Frequency Cited (FC), Number of Uses (NU), Number of Respondents (NR) and Index of Performance (IP). The ICF (Informant Consensus Factor) calculated was important in all categories of diseases averaging 47%.

CONCLUSION

The results obtained, which cover the whole country, delineate the profile of rich wealth of indigenous knowledge on traditional uses of medicinal plants heald by Moroccan society. The total number of 905 plant species listed in this paper, are currently being utilized as medicines and the number is expected to grow as infrastructure allows greater access to unexplored parts of the country. Furthermore, the know how, regarding the plants used, is consistent because the ICF has recorded important values for most diseases treated. Furthermore, in the present paper, we suggested, for authors, some useful recommendations for ethnobotanical field works such as the respect of ethnobotanical standards including checklist of plants with international data base, the deposited voucher specimens, sampling and collection methods.

Potential Application of Some Lamiaceae Species in the Management of Diabetes

Diabetes is one of the most dangerous metabolic disorders, with high rates of mortality worldwide. Since ancient times, medicinal plants have been used in traditional medicine to treat many diseases, including diabetes and its related complications. Plants are widely accepted, affordable, and perceived to have minimal adverse side effects. The Lamiaceae family is a potential source of therapeutic agents for the management of metabolic disorders, including diabetes. Hence, this review paper summarizes the antidiabetic use of Lamiaceae species in folk medicine globally. Furthermore, we present the antidiabetic activities and phytochemical constituents of twenty-three (23) Lamiaceae species and the antidiabetic activity of some notable chemical constituents isolated from some of these Lamiaceae species.

Cinnamoyl Sucrose Esters as Alpha Glucosidase Inhibitors for the Treatment of Diabetes

Cinnamoyl sucrose esters (CSEs) were evaluated as AGIs and their enzyme inhibition activity and potency were compared with gold standard acarbose. The inhibition activity of the CSEs against α-glucosidase and α-amylase depended on their structure including the number of the cinnamoyl moieties, their position, and the presence or absence of the acetyl moieties. The inhibitory values of the CSEs 2–9 generally increases in the order of mono-cinnamoyl moieties < di-cinnamoyl ≤ tri-cinnamoyl < tetra-cinnamoyl. This trend was supported from both in vitro and in silico results. Both tetra-cinnamoyl CSEs 5 and 9 showed the highest α-glucosidase inhibitory activities of 77 ± 5%, 74 ± 9%, respectively, against acarbose at 27 ± 4%, and highest α-amylase inhibitory activities of 98 ± 2%, 99 ± 1%, respectively, against acarbose at 93 ± 2%. CSEs 3, 4, 6, 7, 8 showed desired higher inhibition of α-glucosidase than α-amylase suggesting potential for further development as AGIs with reduced side effects. Molecular docking studies on CSEs 5 and 9 attributed the high inhibition of these compounds to multiple π-π interactions and favorable projection of the cinnamoyl moieties (especially O-3 cinnamoyl) in the enzyme pockets. This work proposes CSEs as new AGIs with potentially reduced side effects.

Phytochemical screening, polyphenols, flavonoids and tannin content, antioxidant activities and FTIR characterization of Marrubium vulgare L. from 2 different localities of Northeast of Morocco

Chemical compositions, biological and antioxidant activities of plants are widely affected by several parameters and conditions, such as geographical and climatic conditions, type of extract (aqueous or organic), as well as the polarity of the extracting solvent. Therefore the present study was the first one designed to study the phytochemical composition, the content of polyphenols, tannins and flavonoids, the antioxidant activities and the chemical composition analysis by FTIR spectroscopic of organic (ethanol, methanol, ethyl Acetate, petroleum ether) and aqueous extracts of Marrubium vulgare L. leaves, collected from two different sampling localities in the North-East of Morocco: Oulad Daoud Zkhanine and the Cape Three Forks. A phytochemical screening was carried out by specific coloring and precipitation reactions. The colorimetric method Folin- Ciocalteu was used for the quantification of total phenolic content. The method of aluminum chloride was employed for the quantification of total flavonoid content and the method of vanillin for the determination of tannins. The antioxidant power was evaluated by the DPPH and ABTS methods. The chemical composition of the organic extracts was analyzed by the FTIR spectroscopy method. Depending on the sampling location of M.vulgare L., the type of extract (aqueous or organic), the polarity of the extracting solvent, and the phytochemical screening revealed the presence of the following secondary metabolites: catechic tannins, terpenoids, polyphenols and flavonoids. The total concentrations of total polyphenols, flavonoids and tannins varied respectively between 0.27 ± 0.1 and 86.91 ± 1.22 μg gallic acid equivalents/mg,6.08 ± 0.17 and 33.82 ± 0.90 μg quercetin equivalents/mg and 2.73 ± 1.15 and 252.68 ± 4.50 μg catechin equivalents/mg. The antioxidant activity that was evaluated by DPPH and ABTS method showed that ethanol extract, methanol and ethyl acetate extract had the highest percentages of inhibition, unlike petroleum ether extract. The inhibitory concentrations (IC₅₀) ranged from 324.55 ± 0.66 to 980 ± 0.62 μg/ml for DPPH and from 107.85 ± 0.19 to 890.74 ± 0.17 μg/ml for ABTS. FTIR spectroscopic analysis has revealed different characteristic peak values with various functional groups in the extracts such as amide, alcohol, phenol compounds. In general, the organic and aqueous extracts of M.vulgare L. that were harvested from Oulad Daoud Zkhanin were richer in secondary metabolites, and showed higher concentrations of polyphenol, flavonoids and tannins. In addition, they revealed a higher antioxidant capacity than the extracts of M. vulgare L.from the Cape Three Forks.

Overall this study highlighted the potential benefits and richness of M.vulgare L. harvested from the two study areas and suggested it as a potential source of natural antioxidants that could be used in the food and pharmaceutical fields.

A review on the structure and pharmacological activity of phenylethanoid glycosides

Phenylethanoid glycosides (PhGs) are compounds made of phenylethyl alcohol, caffeic acid and glycosyl moieties. The first published references about phenylethanoid glycosides concerned the isolation of echinacoside from Echinaceu ungustifolia (Asteraceae) in 1950 and verbascoside from Verbascum sinuatum (Scrophulariaceae) in 1963. Over the past 60 years, many compounds with these structural characteristics have been isolated from natural sources, and most of these compounds possess significant bioactivities, including antibacterial, antitumor, antiviral, anti-inflammatory, neuro-protective, antioxidant, hepatoprotective, and immunomodulatory activities, among others. In this review, we will summarize the phenylethanoid glycosides described in recent papers and list all the compounds that have been isolated over the past few decades. We will also attempt to present and assess recent studies about the separation, extraction, determination, and pharmacological activity of the excellent natural components, phenylethanoid glycosides.

Marrubium vulgare L.: A Phytochemical and Pharmacological Overview

Marrubium vulgare is a plant with high bioactive potential. It contains marrubiin, a labdane diterpene that is characteristic for this genus, as well as a complex mixture of phenolic compounds. According to numerous studies, M. vulgare acts as a good antioxidant agent, and due to this, it could potentially be useful in treatments of cancer, diabetes mellitus, and liver diseases. In addition, its anti-inflammatory, wound-healing, antihypertensive, hypolipidemic, and sedative potential are discussed. Apart from that, its antimicrobial activity, especially against Gram+ bacteria, fungi, herpes simplex virus, and parasites such as Toxoplasma gondii, Trichomonas vaginalis, and Plasmodium berghei-berghei was recorded. Additionally, it could be used as a chicken lice repellent, herbicide, and natural insecticide against mosquito larvae and natural molluscicide. In veterinary medicine, M. vulgare can be used as an anthelmintic against the eggs and larvae of bovine strongyles parasites, and as an antibiotic against bovine mastitis caused by resistant bacterial strains. Due to the mentioned benefits, there is a tendency for the cultivation of M. vulgare in order to ensure high-quality raw material, but more firm scientific evidence and well-designed clinical trials are necessary for the well-established use of M. vulgare herb and its preparations.

Ethnopharmacological review of medicinal plants used to manage diabetes in Morocco

Diabetes is a chronic metabolic disorder which affects millions of people every year. If diabetes is not controlled, it can cause serious damage and a number of health complications. The aim of this paper was to review published ethnobotanical and ethnopharmacological evidences of Moroccan plants with antidiabetic potentials. Publications describing the medicinal plants used for the treatment of diabetes in Morocco were searched from the databases, including Google Scholar, Elsevier, Medline, Web of Science, SCOPUS and Pubmed. Other literature source was also used including books and theses available in library. About 750 literature references were studied, and only 240 research publications based on data from different Moroccan provinces published until June 2019 were included in this review. In total, 255 plants species belonging to 70 families were reported. Compositae and Lamiaceae were mentioned as the most represented families. The frequently used plant species in the dwellers of most regions of Morocco are Trigonella foenum-graecum, Artemesia herba-alba, Nigella sativa, Olea europaea, Allium cepa and Marrubium vulgare. This review provides useful information and current scientific knowledge on the medicinal plants used to manage diabetes in Morocco. Medicinal plants reported should be submitted to chemical, pharmacological and clinical studies to identify pharmacologically active metabolites and to confirm their antidiabetic activity.

Reduction of blood glucose by plant extracts and their use in the treatment of diabetes mellitus; discrepancies in effectiveness between animal and human studies

ETHNOPHARMACOLOGICAL RELEVANCE

The global problem of diabetes, together with the limited access of large numbers of patients to conventional antidiabetic medicines, continues to drive the search for new agents. Ancient Asian systems such as traditional Chinese medicine, Japanese Kampo medicine, and Indian Ayurvedic medicine, as well as African traditional medicine and many others have identified numerous plants reported anecdotally to treat diabetes; there are probably more than 800 such plants for which there is scientific evidence for their activity, mostly from studies using various models of diabetes in experimental animals.

AIM OF THE REVIEW

Rather than a comprehensive coverage of the literature, this article aims to identify discrepancies between findings in animal and human studies, and to highlight some of the problems in developing plant extract-based medicines that lower blood glucose in patients with diabetes, as well as to suggest potential ways forward.

METHODS

In addition to searching the 2018 PubMed literature using the terms 'extract AND blood glucose, a search of the whole literature was conducted using the terms 'plant extracts' AND 'blood glucose' AND 'diabetes' AND 'double blind' with 'clinical trials' as a filter. A third search using PubMed and Medline was undertaken for systematic reviews and meta-analyses investigating the effects of plant extracts on blood glucose/glycosylated haemoglobin in patients with relevant metabolic pathologies.

FINDINGS

Despite numerous animal studies demonstrating the effects of plant extracts on blood glucose, few randomised, double-blind, placebo-controlled trials have been conducted to confirm efficacy in treating humans with diabetes; there have been only a small number of systematic reviews with meta-analyses of clinical studies. Qualitative and quantitative discrepancies between animal and human clinical studies in some cases were marked; the factors contributing to this included variations in the products among different studies, the doses used, differences between animal models and the human disease, and the impact of concomitant therapy in patients, as well as differences in the duration of treatment, and the fact that treatment in animals may begin before or very soon after the induction of diabetes.

CONCLUSION

The potential afforded by natural products has not yet been realised in the context of treating diabetes mellitus. A systematic, coordinated, international effort is required to achieve the goal of providing anti-diabetic treatments derived from medicinal plants.

Antioxidant and antifungal activities of marrubiin, extracts and essential oil from Marrubium vulgare L. against pathogenic dermatophyte strains

OBJECTIVE

Medicinal plants extracts and plant-derived compounds are one of the natural sources for discovering new antifungal agents, the objectives of this work were to investigate for the first time the antidermatophytic, antipathogenic activities of methanol, acetone extracts, and essential oil of Marrubium vulgare L. grown in Tunisia and its active compound marrubiin on pathogenic for animals and humans, such as some dermatophytes and pathogenic for plants, and to evaluate antioxidant activities of different extracts with consideration to their chemical compositions.

MATERIAL AND METHODS

Acetone and methanol extracts were evaluated by HPLC, the essential oil was also analyzed by GC/MS. PCL assay was used to determine the antioxidant activity.

RESULTS

Results showed that methanol and acetone extracts exhibited a significant antioxidant activity (261.41 and 272.90μmol TE/g respectively), while the lowest one was observed in the case of marrubiin and essential oil. The antifungal activity of different extracts, marrubiin and essential oil at two concentrations (20 and 100μg/mL) were screened against the dermatophytes fungi Microsporum gypseum, Microsporum canis, Arthroderma cajetani, Trichophyton mentagrophytes, Trichophyton tonsurans, Epidermophyton floccosum and against two fungi strains (Botrytis cinerea, Pythium ultimum). Among tested extracts, marrubiin at 100μg/mL showed about 50% inhibition for T. mentagrophytes and E. floccosum. The anti-phytopathogenic activity was also carried out, only marrubiin had in activity against B. cinerea at the highest dose (32.40%), while methanol extract of M.vulgare and marrubiin are able to increase the mycelial growth of P. ultimum at the highest concentration (45.15 and 40.30% respectively).

CONCLUSION

In our study, we conclude that M.vulgare and marrubiin can be used as natural antioxidants and antifungal agent for treatment of skin dermatophyte infections.

Spray Drying of a Subcritical Extract Using Marrubium vulgare as a Method of Choice for Obtaining High Quality Powder

White horehound (Marrubium vulgare L.), is a grey-leaved perennial herb, belonging to Lamiaceae family, distributed in Eurasia and northern Africa. Despite the fact that M. vulgare has been used since ancient times in treating diverse diseases, it is only in the last decade or so that scientists have been able to lay the foundation for its potential pharmacological actions from the results observed through the prism of ethnopharmacological use of this species. The novelty of this study was that subcritical water extraction, acknowledged as a powerful extraction technology to recover phenolic compounds, was coupled with spray drying. The subcritical horehound extract, obtained using optimal process parameters, was used as a liquid feed in spray drying. Maltodextrin was used as a carrier in a concentration of 10%. Thus, two M. vulgare powders, carrier-free and 10% MD, were produced. Comprehensive powders characterization was conducted in order to evaluate their quality. Results confirmed that spray drying can be used as a method of choice for obtaining high quality horehound powders which kept the amorphous structure constant after 6 months.

Anil Kumar N, Sharopov F, Ramírez-Alarcón K, Ruiz-Ortega A, Abdulmajid Ayatollahi S, Valere Tsouh Fokou P, Kobarfard F, Amiruddin Zakaria Z, Iriti M, Taheri Y, Martorell M, Sureda A, N. Setzer W, Durazzo A, Lucarini M, Santini A, Capasso R, Adrian Ostrander E, -ur-Rahman A, Iqbal Choudhary M, C. Cho W, Sharifi-Rad J. Antidiabetic Potential of Medicinal Plants and Their Active Components

Diabetes mellitus is one of the major health problems in the world, the incidence and associated mortality are increasing. Inadequate regulation of the blood sugar imposes serious consequences for health. Conventional antidiabetic drugs are effective, however, also with unavoidable side effects. On the other hand, medicinal plants may act as an alternative source of antidiabetic agents. Examples of medicinal plants with antidiabetic potential are described, with focuses on preclinical and clinical studies. The beneficial potential of each plant matrix is given by the combined and concerted action of their profile of biologically active compounds.

The use of a microwave-assisted solvent extraction coupled with HPLC-UV/PAD to assess the quality of Marrubium vulgare L. (white horehound) herbal raw material

INTRODUCTION

Marrubium vulgare is a herbal remedy presents in several European Pharmacopoeias and commonly marketed as white horehound. The chemotaxonomic marker of Marrubium genus is marrubiin and its content may change in response to biotic and abiotic stress.

OBJECTIVE

Development of a microwave-assisted solvent extraction (MASE) methodology suitable for exhaustively extracting marrubiin from M. vulgare leaves, easily applicable to large sets of samples. Evaluation of the influence of copper(II) on marrubiin production.

MATERIAL AND METHODS

M. vulgare leaves were dried, extracted exploiting MASE and analysed via high-performance liquid chromatography ultraviolet photodiode array detection (HPLC-UV/PAD) system. A design of experiments approach was adopted to select the best extraction conditions. Extraction parameters (solvent composition, extraction time and temperature), were studied applying two full factorial experimental designs in a sequential approach. To analyse samples, a rapid HPLC-UV/PAD method was set up.

RESULTS

The best results in terms of marrubiin extraction yield were obtained extracting samples at 120°C with 100% ethanol, for 15 min (3 × 5 min microwave cycles). The developed methodology was successfully applied to matrices grown in Greenhouse conditions and under stress induced by copper(II), selected as model agent for abiotic stress. Progressively decreasing production of marrubiin was evidenced in connection with treatment with 80, 200 and 300 mg/L copper sulphate.

CONCLUSION

An efficient methodology for the extraction and determination of the amount of marrubiin in large sets of samples of M. vulgare plants was developed. Results demonstrated that marrubiin is an easily detectable marker useful for evaluating M. vulgare reaction to stress.

A review of Algerian medicinal plants used in the treatment of diabetes

ETHNOPHARMACOLOGICAL RELEVANCE

Plants are traditionally used in Algeria to treat many disorders, including diabetes mellitus. Knowledge of the plants that are used may provide insight on their properties, for further exploration. This study reviewed all the available published and unpublished reports concerning the use of herbal medicines in the treatment of diabetes in Algeria.

AIM OF THE STUDY

To describe the plants used in Algeria to treat diabetes, as reported in the literature.

MATERIAL AND METHODS

Systematic review of ethnobotanical papers published in the medical literature, from literature databases (Pubmed, Web of Science), as well as Google, for English, French and Arabic -language publication, and a manual search of local libraries and bookshops, as well as the university repository of PhD and master's theses. The reference lists of the papers retrieved were also examined for further papers.

RESULTS

Many plants are cited in the ethnobotanical surveys, but only very few pharmacological studies were found. In the ethnobotanical surveys, 171 plants were reported, from 58 families of which the most often cited were Asteraceae, Lamiaceae and Apiaceae. The plants with the best evidence of use and activity are: Anabasis articulata (Forssk.) Moq., Trigonella foenum-graecum L., Centaurium erythraea Rafn, Artemisia herba-alba Asso, Marrubium vulgare L., Agathophora alopecuroides (Delile) Fenzl ex Bunge, Anabasis articulata (Forssk.) Moq., Hammada elegans (Bunge) Botsch., Helianthemum kahiricum Delile, Salsola baryosma (Schult.) Dandy, Salsola vermiculata L., Olea europaea L.

CONCLUSION

Traditional herbal medicines are still very much used in Algeria to control diabetes. However they are generally poorly characterized and none have been properly tested in man. There is a need for systematic evaluation of the more commonly used plants to confirm their antidiabetic activity, identify possible mechanimss of action, and recommend best use.

Characterization and Quantification of Polyphenols and Triterpenoids in Thinned Young Fruits of Ten Pear Varieties by UPLC-Q TRAP-MS/MS

Large quantities of thinned young pears, a natural source of bioactive compounds, are abandoned as agricultural by-products in many orchards. Hence, ten thinned young pear varieties were systematically investigated in terms of their chemical composition and antioxidant potential. Through ultra-performance liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry (UPLC-Q TRAP-MS/MS), 102 polyphenols and 16 triterpenoids were identified and individually quantified within a short time using multiple reaction monitoring (MRM). Subsequently, the antioxidant capacities of these pears were determined with DPPH assays, and the correlation between total antioxidant activity and each component was analyzed. The results indicated that the bioactive compound content and antioxidant capacity in thinned pears were considerably high. Regarding chemical composition, chlorogenic acid, quinic acid and arbutin were the primary polyphenols and ursolic acid was the predominant triterpenoid, whereas 27 polyphenolic compounds, especially chlorogenic acid and most of the flavan-3-ols, were the main antioxidants in young pears. These findings should provide a scientific basis for the further use of pear fruit by-products.

Effects of butanol fraction of Ziziphus mucronata root ethanol extract on glucose homeostasis, serum insulin and other diabetes-related parameters in a murine model for type 2 diabetes

CONTEXT

Ziziphus mucronata Willd (Rhamnaceae) is currently used in Nigerian traditional treatment of diabetes mellitus. However, detailed information on the antidiabetic potential of the plant parts is presently unknown.

OBJECTIVES

The present study investigated the antidiabetic effects of the butanol fraction of Z. mucronata root (ZMBF) in a type 2 diabetes (T2D) model of rats.

MATERIALS AND METHODS

T2D was induced in rats by feeding a 10% fructose solution ad libitum for two weeks followed by an intraperitoneal injection of streptozotocin (40 mg/kg bw) and the animals were orally treated with ZMBF 150 or 300 mg/kg bw for five days a week for four weeks. Food and fluid intake, body weight changes and blood glucose levels were monitored during the experiment while other blood and organ specific diabetes-associated parameters were measured at the end of the experiment.

RESULTS

After four-week treatment, significantly (p < 0.05) lower blood glucose (19.24 vs 28.96 mmol/L), improved glucose tolerance ability (21.26 vs 28.56 mmol/L), higher serum insulin (131.37 vs 64.20 pmol/L) and liver glycogen (2.40 vs 1.54 mg/g tissue) were observed in the 300 mg/kg ZMBF ingested group compared with the diabetic control group. However, food and fluid intake, body weight gain, HOMA-β, HOMA-IR, serum fructosamine level, hepatic and renal function tests were not significantly (p > 0.05) affected by the treatment of ZMBF.

CONCLUSION

Results of this study suggest that ZMBF treatment, at 300 mg/kg bw, possess antidiabetic activity, but could not ameliorate some diabetes-related parameters in type 2 diabetic rats.

Marrubium vulgare L. Leave Extract: Phytochemical Composition, Antioxidant and Wound Healing Properties

Several factors contribute in wound generation, e.g., accidental traumas or surgery, and in certain cases, this dermal injury may have a devastating outcome. When skin damage occurs, the human body puts in place a sophisticated choreography, which involves numerous repairing processes to restore physiological conditions. Nevertheless, natural healing mechanisms are ineffective towards chronic or non-healing wounds and thus, therapeutic strategies may represent the only beneficial alternative to counteract these tissue insults. Over the years, numerous studies showed the great potential of plants in promoting wound healing, by virtue of their high contents in antioxidant species. These compounds trigger a molecular cascade that collimate into the promotion of reparative processes. In this article, we report on the potential effect on wound healing of Marrubium vulgare L., a medicinal plant well known for several pharmaceutical activities. To this aim, the methanolic extract was prepared and subjected to a phytochemical investigation, quantifying the amount of marrubiin via NMR and drawing the phytochemical fingerprint via high performance liquid chromatography-ultra violet/photodiode-array detection-electrospray/mass (HPLC-UV/PAD-ESI/MS) analysis. Lastly, the antioxidant properties and wound healing potential have been evaluated.

A Reassessment of the Marrubium Vulgare L. Herb's Potential Role in Diabetes Mellitus Type 2: First Results Guide the Investigation toward New Horizons

Despite the wide variety of pharmacological activities described for the Marrubium vulgare L. herb, amazingly, only one clinical trial can be found in scientific literature. It was designed for the evaluation of its antidiabetic activity. Worse, the outcomes of this trial were contradictory to what previous in vivo mice assays had concluded. Therefore, should Marrubium vulgare be ruled out due to its lack of therapeutic potential in diabetes? The authors suggest a reevaluation of the clinical trial methodology to establish valid and final results.

Ethnobotanical survey of medicinal plants used in the traditional treatment of diabetes in Chtouka Ait Baha and Tiznit (Western Anti-Atlas), Morocco

ETHNOPHARMACOLOGICAL RELEVANCE

In Morocco, diabetes mellitus is a major public health problem with more than 1.5 million cases in 2014. Medicinal plants are widely used by the Moroccan population to treat the illness.

AIM OF THE STUDY

The aim of this work is to make an inventory of plant species used in folk medicine for the management of diabetes in Chtouka Ait Baha and Tiznit provinces.

MATERIALS AND METHODS

The survey was carried out by means of semi-structured questionnaires. A total of 380 interviews were conducted with traditional health practitioners and knowledgeable villagers. The data were analyzed through use value (UV), fidelity level (FL) and relative frequency of citation (RFC).

RESULTS

In total, 48 plant species belonging to 25 families were reported. Lamiaceae, Asteraceae and Apiaceae were reported as the most represented families. Six plants are reported for the first time as used in traditional treatment of diabetes and one plant species was previously unknown for its medicinal use to treat diabetes in Morocco. The most frequently cited plant species are Allium sativum L., Salvia officinalis L., Marrubium vulgare L. and Lavandula dentata L. Leaves were the most cited plant part used, decoction is the preferred mode of preparation.

CONCLUSION

This study showed the importance of folk medicine in the healthcare system for the local people living in the study area. The current study represents a useful documentation, which can contribute to preserving knowledge on the use of medicinal plants in this region and to explore the phytochemical and pharmacological potential of medicinal plants.

Antioxidant activity and total phenolic and flavonoids content variations of leaves extracts of white Horehound (Marrubium vulgare Linné) from three geographical origins

OBJECTIFS

To elucidate the effect of the sampling location of Marrubium vulgare L. leaves on phenolic contents and antioxidant proprieties of flavonoids extracts.

MATERIALS AND METHODS

M. vulgare L. leaves were collected from three different geographical locations belonging to northwest Algeria: Tessala (mountain region), M'sila forest (coastal region), and Ain Skhouna (steppe region). The flavonoid extraction was achieved using organic solvents with different polarities (methanol, chloroform, ethyl acetate, and hexane). Folin-Ciocalteu colorimetric method was used for quantification of total phenolic contents, and aluminum chloride assay for quantification of total flavonoid contents. The antioxidant properties of flavonoids extract were studied by free l,l-diphenyl-2-picrylhydrazyl radical-scavenging technique.

RESULTS

Total phenolic and flavonoids concentrations varied respectively between 40.7 and 160mg gallic acid equivalents/g and 27.4 and 66.3mg catechin equivalents/g. The DPPH free radical-scavenging activity shows that the antioxidant activity of the flavonoid extracts varied significantly (P<0.001) depending on the type of the organic solvent used, and the sampling location. The methanol, chloroform and ethyl acetate extracts exhibited the highest percentages of inhibition unlike to the aqueous and hexane extracts. These percentages are ranged from 54.8 to 98.8% at 1000μg/mL. In general, M'sila forest flavonoids extracts showed the highest free radical inhibition capacity; followed by those of Ain Skhouna and Tessala Mountain. The inhibitory concentration 50 (IC₅₀) ranged from 33.7 to 774μg/mL and often exceeded those recorded by phenolic standards (ascorbic acid, gallic acid, caffeic acid, tannic acid and catechin). The phytochemical screening revealed the presence of some flavonoid classes, such as flavans and flavanols.

CONCLUSION

The results suggested a potent antioxidant activity of M. vulgare flavonoids extracts, which may find its application in feature research for the food and the pharmacological industries.

An Insight into a Blockbuster Phytomedicine; Marrubium vulgare L. Herb. More of a Myth than a Reality?

Aerial parts and the root of Marrubium vulgare L. (white horehound) have been traditionally used in Europe and in southern and eastern Mediterranean countries. During colonization, the plant was introduced in America to great levels of popularity because of the simplicity of its growing; it was especially popular in Mexico and Brazil, where it has been known as 'maromba', 'marroio' or 'marroio-branco'. Ethnopharmacological uses of M. vulgare include treating respiratory diseases such as acute or chronic bronchitis, colds and asthma. The plant is also used in cases where there is a lack of appetite or dyspepsia and for diagnosed type II diabetes. It has even been used for antihypertensive therapy. For decades, scientists have carried out extensive research trying to explain these and other pharmacologic actions. It is time to systematize and critically analyse the quality of results found to date. Copyright © 2016 John Wiley & Sons, Ltd.

Hepatoprotective activity of white horehound (Marrubium vulgare) extract against cyclophosphamide toxicity in male rats

The hepatoprotective activity of Marrubium vulgare against cyclophosphamide toxicity in Wistar rats was evaluated. Adult male rats were divided into 4 groups of 6 each: a control group, a group injected with cyclophosphamide (150 mg·kg−1) for 3 days, a group orally given a M. vulgare aqueous extract ((500 mg of dry leaves)·kg−1·day−1) for 30 days then treated with cyclophosphamide, and a group receiving only M. vulgare for 30 days. After 33 days of treatment, activities of alanine amino transferase (ALAT), aspartate amino transferase (ASAT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP) were determined in serum. Moreover, lipid peroxidation level and superoxide dismutase (SOD) activities, catalase (CAT) and glutathione peroxidase (GPx) were measured in liver. Alterations of these hepatic biomarkers and increased lipid peroxidation confirmed cyclophosphamide-induced liver toxicity. Cyclophosphamide also decreased the enzymatic defense system against oxidative stress. However, when this drug was administered in rats given M. vulgare extract, all the biological parameters underwent much less alteration. Administration of M. vulgare extract was found to be beneficial by attenuating cyclophosphamide-induced liver damage. The protective effect of the plant is mainly attributed to its antioxidant properties and the existence of phenolic acids and flavonoids, as highlighted by HPLC-based analysis.

5-Caffeoylquinic acid inhibits invasion of non-small cell lung cancer cells through the inactivation of p70S6K and Akt activity: Involvement of p53 in differential regulation of signaling pathways

In the present study, we investigated the effects and molecular mechanism of 5-caffeoylquinic acid (5-CQA), a natural phenolic compound isolated from Ligularia fischeri, on cell invasion, proliferation and adhesion in p53 wild-type A549 and p53-deficient H1299 non-small cell lung cancer (NSCLC) cells. 5-CQA abrogated mitogen-stimulated invasion, but not proliferation, in both A549 and H1299 cells. In addition, 5-CQA inhibited mitogen-stimulated adhesion in A549 cells only. Anti-invasive activity of 5-CQA in A549 cells was mediated by the inactivation of p70(S6K)-dependent signaling pathway. In contrast, in H1299 cells the inactivation of Akt was found to be involved in 5-CQA-mediated inhibition of cell invasion. Collectively, these findings demonstrate the pharmacological roles and molecular targets of 5-CQA in regulating NSCLC cell fate, and suggest further evaluation and development of 5-CQA as a potential therapeutic agent for the treatment and prevention of lung cancer.

Inhibitory Effects of Physalis alkekengi L., Alcea rosea L., Bunium persicum B. Fedtsch. and Marrubium vulgare L. on Mushroom Tyrosinase

BACKGROUND

The key enzyme in the process of melanin biosynthesis is tyrosinase. Skin hyperpigmentation and browning of foods are undesirable phenomena which tyrosinase represents. Therefore, tyrosinase inhibitors have been used increasingly for medicinal and cosmetic products.

OBJECTIVES

In this study, inhibitory effects of four plants including: physalis alkekengi L., Alcea rosea L., Bunium persicum B. Fedtsch. and Marrubium vulgare L. on diphenolase activity of mushroom tyrosinase were evaluated.

MATERIALS AND METHODS

The inhibitory activities of hydroalcoholic extracts of plants against oxidation of L-Dopa (as a substrate) by mushroom tyrosinase were investigated.

RESULTS

The hydroalcoholic extract of P. alkekengi showed the most tyrosinase inhibitory effect with IC50 of 0.09 mg/mL vs. 0.38, 0.38 and 2.82 mg/mL of B. persicum, A. rosea and M. vulgare, respectively. M. vulgare exhibited uncompetitive inhibition and other plants showed mixed type inhibition on mushroom tyrosinase.

CONCLUSIONS

All plants could inhibit mushroom tyrosinase, but more investigations on human tyrosinase and clinical studies are needed.

Diterpene synthases of the biosynthetic system of medicinally active diterpenoids in Marrubium vulgare

Marrubium vulgare (Lamiaceae) is a medicinal plant whose major bioactive compounds, marrubiin and other labdane-related furanoid diterpenoids, have potential applications as anti-diabetics, analgesics or vasorelaxants. Metabolite and transcriptome profiling of M. vulgare leaves identified five different candidate diterpene synthases (diTPSs) of the TPS-c and TPS-e/f clades. We describe the in vitro and in vivo functional characterization of the M. vulgare diTPS family. In addition to MvEKS ent-kaurene synthase of general metabolism, we identified three diTPSs of specialized metabolism: MvCPS3 (+)-copalyl diphosphate synthase, and the functional diTPS pair MvCPS1 and MvELS. In a sequential reaction, MvCPS1 and MvELS produce a unique oxygenated diterpene scaffold 9,13-epoxy-labd-14-ene en route to marrubiin and an array of related compounds. In contrast with previously known diTPSs that introduce a hydroxyl group at carbon C-8 of the labdane backbone, the MvCPS1-catalyzed reaction proceeds via oxygenation of an intermediate carbocation at C-9, yielding the bicyclic peregrinol diphosphate. MvELS belongs to a subgroup of the diTPS TPS-e/f clade with unusual βα-domain architecture. MvELS is active in vitro and in vivo with three different prenyl diphosphate substrates forming the marrubiin precursor 9,13-epoxy-labd-14-ene, as identified by nuclear magnetic resonance (NMR) analysis, manoyl oxide and miltiradiene. MvELS fills a central position in the biosynthetic system that forms the foundation for the diverse repertoire of Marrubium diterpenoids. Co-expression of MvCPS1 and MvELS in engineered E. coli and Nicotiana benthamiana offers opportunities for producing precursors for an array of biologically active diterpenoids.

Evaluating Antiproliferative and Antioxidant Activity of Marrubium crassidens

PURPOSE

Naturally occurring substances as novel drugs in cancer therapy, at all times, represent a challenge to science since medicinal plants are proving to be brilliant sources of new chemopreventive agents.

METHODS

In the present study, methanol extract from aerial parts of Marrubium crassidens was assessed for its antiproliferative activity in the breast cancer cell line MCF-7 through MTT bioassay using cell viability and cytotoxicity indices. The antioxidant property of M. crassidens extract together with its phenolic and flavonoids content were evaluated, as well.

RESULTS

According to data obtained in the study, M. crassidens exhibited antiproliferative activity with a gradual rise in cytotoxicty effect setting out on 240µg/mL concentration of the extract. Moreover, the RC50 value for antioxidant activity of the extract was determined as 40µg/mL and values for the total phenolic and flavonoids were calculated as 512.64mg gallic acid equivalent and 212.73mg quercetin equivalent per 100g of dry plant material.

CONCLUSION

Generally, the observed antiproliferative and antioxidant properties of M. crassidens could be certified to the high amounts of phenolic and flavonoid content detected in the extract.