Methanolic extract of Origanum vulgare ameliorates type 1 diabetes through antioxidant, anti-inflammatory and anti-apoptotic activity

Origanum vulgare: peroxidase-, superoxide dismutase- and immunomodulatory activities on macrophages activated with Helicobacter pylori derivatives

Helicobacter pylori, invades the gastric mucosa and is one of the causative agents of stomach cancer and peptic ulcers. Origanum vulgare, is a flavouring herb used worldwide. But little is known about the effects of extracts prepared by maceration in cold PBS. This study was aimed at determining the superoxide dismutase (SOD)- and peroxidase (Px)-like antioxidant activities as well as the immunomodulatory activity (anti-inflammatory/pro-inflammatory) of an aqueous extract of O. vulgare by evaluating the production of nitric oxide (NO) in macrophages stimulated with H. pylori derivatives. The cold extract presented SOD-like and Px-like activities with effective concentration 50 (EC50) values of Px = 489.7 ± 48 µg/ml and SOD= 384.7 ± 30 µg/ml. The extract was also capable of modulating the production of NO in macrophages stimulated by H. pylori derivatives by exerting a pro-inflammatory activity at high concentrations and an anti-inflammatory activity at low concentrations.

Evaluation of Chemical Profile and Biological Properties of Extracts of Different Origanum vulgare Cultivars Growing in Poland

This research studied the phenolic content compared with the antioxidant properties of various O. vulgare (Lamiaceae) cultivars grown in Poland. The research results in this paper indicate that the dominant ingredient in all oregano cultivars was rosmarinic acid, known for its strong antioxidant properties. The highest amounts of rosmarinic acid (87.16 ± 4.03 mg/g dm) were identified in the O. vulgare spp. hirtum (Link) Ietsw. Other metabolites identified in the studied extracts include luteolin O-di-glucuronide-O-di-pentoside (30.79 ± 0.38 mg/g dm in the 'Aureum' cultivar), 4'-O-glucopyranosyl-3', 4'-dihydroxy benzyl-protocatechuate (19.84 ± 0.60 mg/g dm in the 'Margerita' cultivar), and p-coumaroyl-triacetyl-hexoside (25.44 ± 0.18 mg/g dm in the 'Margerita' cultivar). 'Hot & spicy' and 'Margerita' cultivars were characterized by the highest activity in eliminating OH• and O2•- radicals. Extracts from Greek oregano had the highest ability to scavenge DPPH radicals and chelate iron ions. This research has also provided new evidence that oregano has anti-migratory, cytotoxic properties and influences the viability of gastric cancer cells (the highest cytotoxicity was attributed to the 'Hot & spicy' cultivar, which performed the worst in antioxidant properties tests). Extracts from the tested cultivars at a concentration of 0.625% effectively inhibited the growth of S. aureus and P. aeruginosa bacteria. It seems that the oregano grown in Poland is of good quality and can be successfully grown on a large scale if the appropriate use is found.

Polyphenols in edible plant leaves: an overview of their occurrence and health properties

Edible plant leaves (EPLs) constitute a major renewable functional plant biomass available all year round, providing an essential source of polyphenols in the global diet. Polyphenols form a large family of antioxidant molecules. They protect against the harmful effects of free radicals, strengthen immunity and stimulate the body's natural defenses thanks to their antibacterial and antiviral functions. This study refers to phenolic compounds from 50 edible plant leaves divided into four categories: green leafy vegetables, underutilized leafy vegetables, leafy spices and leafy drinks. It provides data on the identification, occurrence and pharmacological functions of polyphenols contained in EPLs, and provides a better understanding of trends and gaps in their consumption and study. Certain EPLs, such as moringa (Moringa oleifera Lam.), tea (Camellia sinensis L.) and several leafy spices of the Lamiaceae family, reveal important characteristics and therapeutic potential. The polyphenol composition of EPLs makes them functional plants that offer relevant solutions in the fight against obesity, the management of food insecurity and the prevention of chronic diseases.

Overview of Ethnobotanical-Pharmacological Studies Carried Out on Medicinal Plants from the Serra da Estrela Natural Park: Focus on Their Antidiabetic Potential

The Serra da Estrela Natural Park (NPSE) in Portugal stands out as a well-preserved region abundant in medicinal plants, particularly known for their pharmaceutical applications in diabetes prevention and treatment. This comprehensive review explores these plants' botanical diversity, traditional uses, pharmacological applications, and chemical composition. The NPSE boast a rich diversity with 138 medicinal plants across 55 families identified as traditionally and pharmacologically used against diabetes globally. Notably, the Asteraceae and Lamiaceae families are prevalent in antidiabetic applications. In vitro studies have revealed their significant inhibition of carbohydrate-metabolizing enzymes, and certain plant co-products regulate genes involved in carbohydrate metabolism and insulin secretion. In vivo trials have demonstrated antidiabetic effects, including glycaemia regulation, insulin secretion, antioxidant activity, and lipid profile modulation. Medicinal plants in NPSE exhibit various activities beyond antidiabetic, such as antioxidant, anti-inflammatory, antibacterial, anti-cancer, and more. Chemical analyses have identified over fifty compounds like phenolic acids, flavonoids, terpenoids, and polysaccharides responsible for their efficacy against diabetes. These findings underscore the potential of NPSE medicinal plants as antidiabetic candidates, urging further research to develop effective plant-based antidiabetic drugs, beverages, and supplements.

Potential Protective Effects of Ruta Chalepensis L. Extracts Against Gentamicin-Induced Nephrotoxicity via Reduction on Apoptotic, DNA Damage and Oxidative Stress Markers in Mice

In this study, the protective effects of Ruta chalepensis L. extracts on the extent of tissue damage in gentamicin-induced nephrotoxicity have been investigated. Ruta chalepensis L. extracts were prepared by subcritical water and ultrasound-assisted organic solvent extraction methods. Protective activity of Ruta chalepensis L. extracts on Gentamicin-induced nephrotoxicity is investigated by apoptotic, DNA damage, oxidative stress markers and evaluating histopathological in kidney tissue of mice. Gentamicin significantly increased Caspase-3 and -8 activities, NO levels, serum creatinine and BUN, while 8-OHdG and MDA levels were significantly decreased with Ruta chalepensis L. extract treatment. In addition, Ruta chalepensis L. extracts treatment significantly increased CAT and SOD activities. Histopathological alterations in Gentamicin group were significantly diminished by application of Ruta chalepensis L. extracts. These results suggest that treatment with Ruta chalepensis L. extracts may ameliorate renal dysfunction and structural damage through the reduction of oxidative stress and apoptosis in the kidney.

A Comparative Evaluation of Antioxidant Activity of Extract and Essential Oil of Origanum onites L. In Vivo

In the present study, the effects of Origanum onites L. extract and essential oil of O. onites L. on the antioxidant status of the liver and brain of mice were investigated. Due to certain disadvantages of essential oils, such as poor solubility, high volatility and sensitivity to UV light and heat, formulation of liposomes with Oregano essentials (OE) was optimized and used in this study. The results demonstrated that the best composition of the lipid carriers and OE were conducted in terms of the polydispersity index (PDI), mean particle size and encapsulation efficiency (EE). For further study the LE4 formulation was used, which contained Lipoid S100 at 45 mg, Lipoid S75 at 45 mg and 90 mg of EO. The administration of O. onites L. extract to mice for 21 days significantly decreased the glutathione (GSH) level in the livers and brains of the mice as well as the malondialdehyde (MDA) concentration in the livers. In the brains of the mice, MDA level significantly increased after this extract consumption. Whereas liposomes with OE significantly decreased GSH concentration in the mouse brain and MDA concentration in the mouse liver, there was an increased (p > 0.05) GSH level in the liver and MDA concentration in the brain of mice compared with the control group. It was found that both O. onites. ethanolic extract as well as liposomes with OE of this plant material affect the antioxidant status in the livers and brains of mice.

Pathways to healing: Plants with therapeutic potential for neurodegenerative diseases

Some of the greatest challenges in medicine are the neurodegenerative diseases (NDs), which remain without a cure and mostly progress to death. A companion study employed a toolkit methodology to document 2001 plant species with ethnomedicinal uses for alleviating pathologies relevant to NDs, focusing on its relevance to Alzheimer's disease (AD). This study aimed to find plants with therapeutic bioactivities for a range of NDs. 1339 of the 2001 plant species were found to have a bioactivity from the literature of therapeutic relevance to NDs such as Parkinson's disease, Huntington's disease, AD, motor neurone diseases, multiple sclerosis, prion diseases, Neimann-Pick disease, glaucoma, Friedreich's ataxia and Batten disease. 43 types of bioactivities were found, such as reducing protein misfolding, neuroinflammation, oxidative stress and cell death, and promoting neurogenesis, mitochondrial biogenesis, autophagy, longevity, and anti-microbial activity. Ethno-led plant selection was more effective than random selection of plant species. Our findings indicate that ethnomedicinal plants provide a large resource of ND therapeutic potential. The extensive range of bioactivities validate the usefulness of the toolkit methodology in the mining of this data. We found that a number of the documented plants are able to modulate molecular mechanisms underlying various key ND pathologies, revealing a promising and even profound capacity to halt and reverse the processes of neurodegeneration.

Potential Mechanisms of Imidacloprid-Induced Neurotoxicity in Adult Rats with Attempts on Protection Using Origanum majorana L. Oil/Extract: In Vivo and In Silico Studies

Imidacloprid (IMI) insecticide is rapidly metabolized in mammals and contributes to neurotoxicity via the blocking of nicotinic acetylcholine receptors, as in insects. Origanum majorana retains its great antioxidant potential in both fresh and dry forms. No data is available on the neuroprotective effect of this plant in laboratory animals. In this context, aerial parts of O. majorana were used to prepare the essential oil (OMO) and methanol extract (OME). The potential neuroprotective impact of both OMO and OME against IMI-induced neurotoxicity in rats was explored. Forty-two rats were divided into 6 groups, with 7 rats in each one. Rats were daily administered the oral treatments: normal saline, OMO, OME, IMI, IMI + OMO, and IMI + OME. Our results revealed the identification of 55 components in O. majorana essential oil, most belonging to the oxygenated and hydrocarbon monoterpenoid group. Moreover, 37 constituents were identified in the methanol extract, mostly phenolics. The potent neurotoxic effect of IMI on rats was confirmed by neurobehavioral and neuropathological alterations and a reduction of both acetylcholine esterase (AchE) activity and dopamine (DA), serotonin (5HT), and γ-aminobutyric acid (GABA) levels in the brain. Exposure of rats to IMI elevates the malondialdehyde (MDA) levels and reduces the antioxidant capacity. IMI could upregulate the transcription levels of nuclear factor-κB (NF-κB), interleukin-1 β (IL-1β), and tumor necrosis factor (TNF-α) genes and express strong caspase-3 and inducible nitric oxide synthase (iNOS) immunostaining in most examined brain areas. On the other hand, rats coadministered OMO or OME with IMI showed a marked improvement in all of the studied toxicological parameters. In conclusion, cotreatment of O. majorana extracts with IMI can protect against IMI neurotoxicity via their potent antioxidant, anti-inflammatory, and anti-apoptotic effects. Thus, we recommend a daily intake of O. majorana to protect against insecticide's oxidative stress-mediated neuroinflammatory stress and apoptosis. The molecular docking study of linalool, rosmarinic acid, γ-terpene, and terpene-4-ol justify the observed normalization of the elevated iNOS and TNF-α levels induced after exposure to IMI.

Redox Remodeling by Nutraceuticals for Prevention and Treatment of Acute and Chronic Inflammation

Antioxidant-rich dietary regimens are considered the best practice to maintain health, control inflammation, and prevent inflammatory diseases. Yet, nutraceuticals as food supplements are self-prescribed and purchasable over the counter by healthy individuals for the purpose of beneficial effects on fitness and aging. Hence, the effectiveness, safety, and correct intake of these compounds need to be better explored. Since redox-modulating activity of these compounds appears to be involved in activation and or suppression of immune cells, the preventive use of nutraceuticals is very attractive even for healthy people. This review focuses on redox- and immunomodulating nutraceuticals in the context of diabetes mellitus (DM). In fact, DM is an illustrative disease of latent and predictable inflammatory pathogenetic processes set out and sustained by oxidative stress. DM has been thoroughly investigated through in vitro and in vivo models. Furthermore, human DM is characterized by uncontrolled levels of glucose, a pivotal factor shaping immune responses. Hence, antioxidant nutraceuticals with multifaced activities, including glucose keeping, are described here. A greater number of such multi-player nutraceuticals might be identified using DM animal models and validated in clinical settings on genetic and environmental high-risk individuals.

Oregano as a potential source of antidiabetic agents

Oregano is the name given to a great variety of herbs belonging mainly to the Lamiaceae and Verbenaceae botanical families. Oregano species are rich sources of phytochemicals such as phenolic compounds like rosmarinic acid, salvianolic acid, and luteolin, among others. A few articles have previously accessed some potential pharmacological bioactivities of oregano plants; however, none has focused on the antidiabetic studies. This review aims to summarize recent studies about the potential effect of phenolic compounds from oregano plant species. The reports were retrieved from electronic databases such as PubMed, Web of Science, National Center for Biotechnology Information (NCBI), and Scopus. In addition, articles related to the mentioned topics and published between 2004-2022 were selected. The results from this study show that the antidiabetic pharmacological reports of oregano phenolic compounds are mainly in vitro reports. Therefore, the diversity of oregano species yields a broad variety of phenolic constituents, where preclinical and clinical studies are strongly recommended.

Hypoglycemic effect of rosmarinic acid-rich infusion (RosCE) from Origanum vulgare in alloxan-induced diabetic rats

Origanum vulgare, known for its medicinal value, is officially accepted in many countries. The flowers and leaves are used globally in homeopathy. In Brazilian folk medicine, O. vulgare has been used to treat diabetes mellitus. This study evaluated the hypoglycemic activity of an infusion extract (RosCE) of commercially available O. vulgare leaves in alloxan-induced diabetic rats. Oral administration of RosCE resulted in the reduction of blood glucose levels after the first day of treatment, compared to the diabetic control group. These results showed that RosCE displays hypoglycemic activity, which may be due to the combined effect of rosmarinic acid, and other minor compounds. Reversed phase-high performance liquid chromatography-diode array detection was used to identify and quantify the major constituents of RosCE. This study presents evidence that supports the folkloric use of O. vulgare for the treatment of hyperglycemia, confirming the use of its infusion as an antidiabetic herbal medicine.

Exploring the plant-derived bioactive substances as antidiabetic agent: An extensive review

Diabetes mellitus (DM) is a metabolic syndrome. Diabetes has become more common in recent years. Chemically generated drugs are used to lessen the effects of DM and its following repercussions due to unpleasant side effects such as weight gain, gastrointestinal issues, and heart failure. On the other hand, medicinal plants could be a good source of anti-diabetic medications. This article aims to determine any plant matrix's positive potential. Food restriction, physical activity, and the use of antidiabetic plant-derived chemicals are all being promoted as effective ways to manage diabetes because they are less expensive and have fewer or no side effects. This review focuses on antidiabetic plants, along with their bioactive constituent, chemically characterization, and plant-based diets for diabetes management. There is minimal scientific data about the mechanism of action of the plant-based product has been found. The purpose of this article is to highlight anti-diabetic plants and plant-derived bioactive compounds that have anti-diabetic properties. It also provides researchers with data that may be used to build future strategies, such as identifying promising bioactive molecules to make diabetes management easier.

Phenethyl ester of rosmarinic acid attenuates autoimmune responses during type 1 diabetes development in mice

AIMS

Rosmarinic acid (RA) is a polyphenol that occurs in plants of the Lamiaceae family. Phenethyl ester of RA (PERA), a novel RA derivative, has been developed and evaluated in vivo in an animal model of type 1 diabetes (T1D).

METHODS

T1D was induced in male C57BL/6 mice using multiple low doses of streptozotocin (STZ) administered intraperitoneally for 5 consecutive days. Intraperitoneal administration of PERA (2.5 mg/kg bw) began from the first STZ injection and continued for 20 days.

KEY FINDINGS

PERA-treated mice exhibited lower incidence of T1D (monitored up to 38 days from the disease induction), and fluorescent histochemical analysis showed that their pancreatic islets expressed more insulin. PERA treatment significantly down-regulated the proportions of CD11b+ and CD11c+ myeloid cells in the immune cell infiltrates in the pancreatic islets early during T1D pathogenesis (on day 9 after T1D induction), while on day 15, PERA significantly reduced the proportions of CD11c+, CD8+, Th1 and Th17 cells. Simultaneously, it was found that the cells from the pancreatic infiltrates of PERA-treated mice produced significantly less reactive oxygen species than cells from the control group.

SIGNIFICANCE

These findings suggest that PERA efficiently prevented T1D development in mice. Interestingly, PERA attenuated the inflammatory process in the islets through temporally specific interference with the innate and adaptive immune response and therefore shows great promise for further clinical evaluation as a novel T1D therapeutic.

The efficacy of Origanum majorana nanocubosomal systems in ameliorating submandibular salivary gland alterations in streptozotocin-induced diabetic rats

Diabetes mellitus is a challenging health problem. Salivary gland dysfunction is one of its complications. Current treatments possess numerous adverse effects. Therefore, herbal extracts have emerged as a promising approach for safe and effective treatment. However, they are required in large doses to achieve the desired effect. Accordingly, Origanum majorana extract (OE) was incorporated into nano-sized systems to enhance its biological effects at lower dosages. OE was standardized against rosmarinic acid (RA) and then loaded into nano-cubosomal (NC) systems via a 2³ full-factorial design. Two optimum nano-systems at different drug loads (2.08 or 1.04 mg-RA/mL) were selected and assessed in vivo to compare their effects in streptozotocin-induced diabetic rats against conventional OE (2.08 mg-RA/mL). Blood glucose was evaluated weekly. Submandibular salivary glands were processed for histopathological examination and nuclear factor-erythroid 2-related factor 2 (Nrf2), Kelch-like ECH-associated protein 1 (Keap1), and p38-MAPK gene expression analysis. NC systems were successfully prepared and optimized where the optimum systems showed nano-sized vesicles (210.4–368.3 nm) and high zeta potential values. In vivo results showed a significant lower blood glucose in all treated groups, with an exceptional reduction with NC formulations. Marked histopathological improvement was observed in all OE-treated groups, with OE-NC4 (2.08 mg-RA/mL) demonstrating the best features. This was supported by RT-PCR; where the OE-NC4 group recorded the highest mean value of Nrf2 and the least mean values of Keap1 and p38-MAPK, followed by OE-NC3 and OE groups. In conclusion, OE-loaded NC enhanced the anti-hyperglycemic effect of OE and ameliorated diabetic gland alterations compared to conventional OE. Thus, cubosomal nano-systems could be anticipated as potential carriers for the best outcome with OE.

Chemical Components and Biological Effects of Genus Origanum

The plants from genus Origanum are common folk Chinese herbs used to treat a variety of diseases. They are also used as a spice, a seasoning, and an ornament. Origanum plants are rich in essential oils and also have other compounds including terpenoids, flavonoids, organic acids, and sterols. They have a variety of biological activities such as antispasmodic, anti-inflammatory, growth-promoting, antibacterial, antioxidant, and anticancer properties. The chemical components and biological effects of genus Origanum were summarized by different scientific databases such as Web of Science, SciFinder, Baidu Scholar, PubMed, ScienceDirect, and SpringerLink. In conclusion, recent studies were mainly focused on the activities of their essential oils. The research studies for nonvolatile constituents and their pharmacological activities are few. Therefore, research on compounds in genus Origanum plants can be strengthened and their application prospect can be explored so as to make better use of the resources of these plants.

Methanolic Extract of Sambucus ebulus Ameliorates Clinical Symptoms in Experimental Type 1 Diabetes through Anti-Inflammatory and Immunomodulatory Actions

Objective

Sambucus ebulus (SE), a famous traditional Iranian medicine, is grown in the north of Iran. As a traditional medicine with anti-inflammatory effects, SE has been utilized against inflammatory joint diseases, insect bites, infectious wounds, edema, and eczema. Type1 diabetes, is an autoimmune disease, characterized by the destruction of pancreatic beta cells by the immune system. For the first time, we investigated the effect of methanolic extract of SE on CD4+, CD8+ and regulatory T cells in experimental type 1 diabetes (T1D).

Materials and Methods

In this experimental study, fifty-six C57BL\6 mice in 8 groups (G1-G8), were enrolled. Diabetes was induced by a multiple low-dose streptozotocin (MLDS) protocol and mice were daily treated with SE extract at 200 and 400 mg/kg doses, for 35 days. Fasting blood glucose was weekly measured by a glucometer. Islets insulin content was analyzed by immunohistochemistry. Percentage of CD4+, CD8+ and regulatory T cells and cytokines production levels were evaluated by flow cytometer and ELISA, respectively.

Results

The clinical symptoms of diabetes were significantly alleviated in G2 group mice which received 400 mg/ kg SE extract. Immunohistochemistry analysis showed that the insulin content of islets increased in G2 group mice. Immunophenotyping analysis indicated that the percentage of CD4+ and CD8+ T cells in G2 group mice was significantly decreased. SE extract significantly increased the percentage of regulatory T cells. The extract in G2 and G4 groups mice significantly decreased IFN-γ and IL-17levels. The extract significantly increased IL-10 in G2 group mice.

Conclusion

The protective effect of SE extract in MLDS-induced diabetes could be partly due to a decrease of CD4+ and CD8+ T cells and an increase of Treg cells resulting in an inflammation reduction in the pancreatic islets.

Antimicrobial and toxicological evaluation of Origanum vulgare: an in vivo study

Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin alongwith marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.

Genetic and Flower Volatile Diversity in Natural Populations of Origanum vulgare subsp. hirtum (Link) Ietsw. in Bulgaria: Toward the Development of a Core Collection

We studied the genetic and flower volatile diversity in natural populations of Origanum vulgare subsp. hirtum (Link) Ietsw. in Bulgaria using simple sequence repeat (SSR) and sequence-related amplified polymorphism (SRAP) markers and gas chromatography/mass spectrometry (GC/MS) analysis of flower volatiles from individual plants. Two regions, including the Kresna Gorge and Eastern Rhodopes, typical for the species comprising eight populations and 239 individual plants were included in this study. An analysis with 11 SSR markers and eight SRAP primer combinations showed that SRAP markers were substantially more informative than the SSR markers and were further used for genetic diversity analysis. The results showed low-range to mid-range genetic differentiation between the populations with pairwise fixation index (Fst) values ranging between 0.0047 and 0.11. A total of 10 genetic clusters were identified. An analysis of the flower volatile diversity identified a total of 63 compounds with the vast majority of plants belonging to the carvacrol chemotype and just a single plant to the thymol chemotype. Large deviations were observed for individual compounds within each region as well as within the populations. Hierarchical clustering showed a clear sample grouping based on the two different regions. In addition, an in-depth analysis identified six major and 23 minor metabolite clusters. The overall data set and cluster analysis were further used for the development and testing of a simple and straightforward strategy for the selection of individual plants for the development of a core collection representing the sampled natural populations for this species in Bulgaria. The proposed strategy involves precise genetic clustering of the tested plants followed by the selection of a minimal set from each genetic cluster representing the different metabolite clusters. The selected core set was further compared with a core set extracted by the PowerCore software. A comparison of the genetic and metabolic affiliation of the members of both sets showed that the reported approach selected representatives from each genetic cluster and minor metabolic cluster, whereas some metabolic clusters were unrepresented in the PowerCore set. The feasibility and efficiency of applying the pointed strategy for the development of a core collection representing both the genetic and metabolite diversity of natural populations in aromatic and medicinal plants toward subsequent steps of selection and breeding are discussed.

Antioxidant and anticancer potentials of edible flowers: where do we stand?

Edible flowers are attracting special therapeutic attention and their administration is on the rise. Edible flowers play pivotal modulatory roles on oxidative stress and related interconnected apoptotic/inflammatory pathways toward the treatment of cancer. In this review, we highlighted the phytochemical content and therapeutic applications of edible flowers, as well as their modulatory potential on the oxidative stress pathways and apoptotic/inflammatory mediators, resulting in anticancer effects. Edible flowers are promising sources of phytochemicals (e.g., phenolic compounds, carotenoids, terpenoids) with several therapeutic effects. They possess anti-inflammatory, anti-diabetic, anti-microbial, anti-depressant, anxiolytic, anti-obesity, cardioprotective, and neuroprotective effects. Edible flowers potentially modulate oxidative stress by targeting erythroid nuclear transcription factor-2/extracellular signal-regulated kinase/mitogen-activated protein kinase (Nrf2/ERK/MAPK), reactive oxygen species (ROS), nitric oxide (NO), malondialdehyde (MDA) and antioxidant response elements (AREs). As the interconnected pathways to oxidative stress, inflammatory mediators, including tumor necrosis factor (TNF)-α, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukins (ILs) as well as apoptotic pathways such as Bcl-2-associated X protein (Bax), Bcl-2, caspase and cytochrome C are critical targets of edible flowers in combating cancer. In this regard, edible flowers could play promising anticancer effects by targeting oxidative stress and downstream dysregulated pathways.

Hypoglycemic activity of Origanum vulgare L. and its main chemical constituents identified with HPLC-ESI-QTOF-MS

Origanum vulgare L. (O. vulgare) is an important medicine food homology in diabetes. The present study aimed to assess the hypoglycemic effect of the leaf extract of O. vulgare in HepG2 and HepG2-GFP-CYP2E1 (E47) cells, and disclose its potential active components by the HPLC-ESI-QTOF-MS method. Firstly, we evaluated the anti-diabetic capacity of the leaf extract of O. vulgare through inhibition of α-glucosidase activity, promotion of glucose uptake, inhibition of glycosylation and relieving of oxidative stress. Secondly, the promoter activity, the mRNA and protein expression of PEPCK and SREBP-1c, and the expression of CPY2E1 and GLUT2 in the O. vulgare mediated anti-diabetic capacity were analyzed in HepG2 and E47 cells. Finally, HPLC-ESI-QTOF-MS analysis was performed to identify the herb's main components under 280 nm irradiation. In vitro assays demonstrated that the extract inhibited α-glucosidase activity, promoted glucose uptake, inhibited glycosylation and relieved oxidative stress, which suggested that O. vulgare leaf extract has a strong hypoglycemic capacity. Moreover, mechanistic analysis also showed that the extract decreased the promoter activity and the mRNA and protein expression of PEPCK and SREBP-1c. In addition, the extract inhibited the expression of CPY2E1 and enhanced the expression of GLUT2. Moreover, the UV chromatogram at 280 nm showed six main peaks, identified as amburoside A (or 4-(3',4'-dihydroxybenzoyloxymethyl) phenyl O-β-d-glucopyranoside), luteolin 7-O-glucuronide, apigenin 7-O-glucuronide, rosmarinic acid, lithospermic acid and a novel compound, demethylbenzolignanoid, based on accurate MS data. This work supported the ethnopharmacological usage of O. vulgare as an antidiabetic herbal medicine or dietary supplement and identified its main phenolic compounds.

Nutraceuticals against Oxidative Stress in Autoimmune Disorders

Antioxidant mechanisms are constituted of enzymes, endogenous, and non-enzymatic, exogenous, which have the role of counterbalancing oxidative stress. Intake of these compounds occurs in the diet. Vegetables, plants, and fruits contain a wide range of alkaloids, polyphenols, and terpenoids which are called “phytochemicals”. Most of these substances are responsible for the positive properties of fruits and vegetables, which are an essential part of a healthy life with roles in ameliorating chronic illnesses and favoring longevity. Nutraceuticals are substances contained in a food or fragment of it influencing health with positive effects on health helping in precenting or treating disorders. We conducted a review illustrating the principal applications of nutraceuticals in autoimmune disorders. Literature reported several studies about exogenous dietary antioxidant supplementation in diverse autoimmune diseases such as rheumatoid arthritis, lupus, diabetes, and multiple sclerosis. In these pathologies, promising results were obtained in some cases. Positive outcomes were generally associated with a reduction of oxidative stress parameters and a boost to antioxidant systems, and sometimes with anti-inflammatory effects. The administration of exogenous substances through food derivates or dietary supplements following scientific standardization was demonstrated to be effective. Further bias-free and extended studies should be conducted that include ever-increasing oxidative stress biomarkers.

A Review of the Phytochemistry and Antimicrobial Properties of Origanum vulgare L. and Subspecies

Origanum vulgare L. (O. vulgare) is an important medicinal herb of the family Lamiaceae. In the current study, we explained the critical evaluation of traditional uses, the phytochemistry and the antimicrobial properties of O. vulgare and its subspecies, with a focus on the mechanisms of actions of the most important phytochemicals from O. vulgare subspecies. The most important phytochemicals of O. vulgare are volatile (essential oil) and non-volatile phenolic compounds (phenolic acids & flavonoids). The constituents of the O. vulgare essential oil (EO) include high percentages of thymol and carvacrol with excellent antimicrobial activity alone or in combination with other antibiotics. Interesting results have been reported the remarkable antimicrobial activities of infusion or tea products of O. vulgare with a high amount of EO against multidrug-resistant bacterial and fungal microorganism (such as Escherichia coli, Staphylococcus aureus, Candida albicans and Pseudomonas aeruginosa). The most important antibacterial mechanisms of O. vulgare are enzyme inhibition, efflux pump inhibition, ATP depletion, biofilm formation inhibition and cytoplasmic membrane damage. The antimicrobial activity of the hirtum subspecies has been confirmed in different in-vitro and in-vivo studies. The present review confirms the clinical and preclinical research showing the O. vulgare and its subspecies antimicrobial effects.

Phytochemical constituents, biological activities, and health-promoting effects of the genus Origanum

Origanum species are mostly distributed around the Mediterranean, Euro-Siberian, and Iran-Siberian regions. Since time immemorial, the genus has popularly been used in Southern Europe, as well as on the American continent as a spice now known all over the world under the name "oregano" or "pizza-spice." Origanum plants are also employed to prepare bitter tinctures, wines, vermouths, beer, and kvass. The major components of Origanum essential oil are various terpenes, phenols, phenolic acids, and flavonoids with predominant occurrence of carvacrol and thymol (with reasonable amounts of p-cymen and -terpinene) or of terpinene-4-ol, linalool, and sabinene hydrate. Many species of Origanum genus are used to treat kidney, digestive, nervous, and respiratory disorders, spasms, sore throat, diabetes, lean menstruation, hypertension, cold, insomnia, toothache, headache, epilepsy, urinary tract infections, etc. Origanum essential oil showed potent bioactivities owing to its major constituents' carvacrol, thymol, and monoterpenes. Several preclinical studies evidenced its pharmacological potential as antiproliferative or anticancer, antidiabetic, antihyperlipidemic, anti-obesity, renoprotective, antiinflammatory, vasoprotective, cardioprotective, antinociceptive, insecticidal, and hepatoprotective properties. Its nanotechnological applications as a promising pharmaceutical in order to enhance the solubility, physicochemical stability, and the accumulation rate of its essential oils have been investigated. However, Origanum has been reported causing angioedema, perioral dermatitis, allergic reaction, inhibition of platelet aggregation, hypoglycemia, and abortion. Conclusive evidences are still required for its clinical applications against human medical conditions. Toxicity analyses and risk assessment will aid to its safe and efficacious application. In addition, elaborate structure-activity studies are needed to explore the potential use of Origanum-derived phytochemicals as promising drug candidates.

The Applications of Origanum Vulgare and Its Derivatives in Human, Ruminant and Fish Nutrition – A Review

Origanum vulgare L. is an aromatic enduring herb that belongs to Lamiaceae family. The bioactive constituents of this herb, such as carvacrol and thymol possess several medicinal properties, such as antioxidant, antidiabetic, anti-inflammatory, antimicrobial, antiviral, antiparasitic, anti-neoplastic, and immune modulatory. Moreover, it is considered a standard natural, less toxic, and residue free feed additive, that is successfully used in livestock and fish. Additionally, in human, Origanum vulgare is extensively used with promising health benefits against respiratory, digestive and urinary disorders. This review casts light on description, chemical composition and structure of Origanum vulgare, as well as its therapeutic applications in human and its biological activities in ruminants and fish, data that will be possibly useful for physiologists, nutritionists and veterinarians.

Charting the structural and thermodynamic determinants in phenolic acid natural product - cyclodextrin encapsulations

Cyclodextrins are pliable platforms that have served to optimize the pharmaceutic profile of numerous compounds and to enhance the stability of natural food additives. Caffeic and rosmarinic acid are natural products with proven health benefits, though their full therapeutic potential has not been exploited. To enhance their pharmaceutic profile, we developed cyclodextrin-based formulates and unveiled their thermodynamic and structural principles. The complexes' stoichiometry was determined by ESI-MS. Solid-state and liquid NMR spectroscopy revealed the interactions and the topographical location of the caffeic and rosmarinic acid inside the cyclodextrin cavity. The theoretically analyzed HP-β-CD's degree of substitution (DS) of caffeic and rosmarinic acids can explain the intensities obtained by 2D NOESY experiments. The thermodynamics and the affinity of the complexes were evaluated through isothermal titration calorimetry. In addition, the rosmarinic and caffeic acids as, also, their complexes showed considerable antimicrobial activity against common food spoilage and pathogenic bacteria. The generated data could provide the basis to understand the structural and thermodynamic determinants implicated in natural products - CD recognition and to develop platforms for the optimization of their pharmaceutical and stability profiles in order to be utilized as safe and stable natural antimicrobial food additives.Communicated by Ramaswamy H. Sarma.

Biological Efficacy of Essential Oils and Plant Extracts of Cultivated and Wild Ecotypes of Origanum vulgare L

Current study describes discrepancy in biological efficacy of methanolic and ethanolic extracts and essential oil procured from cultivated and wild accessions of Origanum vulgare. Simultaneously, quantification of carvacrol, thymol, caryophyllene, ocimene, and terpinen-4-ol contents was determined via GC-MS and GC in both accessions. The results revealed significantly a higher antioxidant potential by methanolic extracts displaying IC₅₀ of 19.9 μg/ml compared to essential oil with IC₅₀ of 10 μg/ml, and ethanolic extracts were found to be less effective even at the concentration of 3 μg/ml. However, essential oil from wild and cultivated accessions of O. vulgare exhibited significantly high antimicrobial activity against all 39 bacteria, 16 fungi, and 2 yeast species tested due to higher concentrations of carvacrol and thymol as revealed by GC analysis. Inhibition of tyrosinase activity in a C6 cell line displayed 81.0%–87.0% depigmentation potential of the methanolic extracts, while ethanolic extracts revealed a maximum of 88.54–99.02% inhibition of reactive oxygen species (ROS) in H₂O₂-treated cells. Hence, the study determines efficacy of essential oil against microbial pathogenesis, methanolic extracts as potent depigmentation agents, and ethanolic extracts as potent free radical scavenger.

Effects of dietary Origanum vulgare on gilthead seabream (Sparus aurata L.) immune and antioxidant status

Origanum sp. is a very common genus of aromatic plants worldwide distributed around the Mediterranean area and O. vulgare (oregano) is the most important species of this genus throughout the world. Due the known medicinal properties of oregano, the effect of diets enriched with 0% (control), 0.5% and 1% oregano leaves powder was studied on the growth, immune and antioxidant status of gilthead seabream (Sparus aurata L.). Fish fed with oregano 0.5% and 1% enriched diets improved both humoral (IgM and bactericidal activity in skin mucus and protease activity in serum) and cellular (head kidney leucocytes phagocytic ability) immunity at 15 and 30 days. Furthermore, the addition of oregano did not provoke any significant effect neither in the growth promotion nor in the liver antioxidant enzymes activity studied in the serum and skin mucus. The possibility of using O. vulgare as a functional additive to fish diet is discussed.

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.

Therapeutic Potential of Rosmarinic Acid: A Comprehensive Review

Naturally occurring food-derived active ingredients have received huge attention for their chemopreventive and chemotherapy capabilities in several diseases. Rosmarinic acid (RA) is a caffeic acid ester and a naturally-occurring phenolic compound in a number of plants belonging to the Lamiaceae family, such as Rosmarinus officinalis (rosemary) from which it was formerly isolated. RA intervenes in carcinogenesis through different ways, including in tumor cell proliferation, apoptosis, metastasis, and inflammation. On the other hand, it also exerts powerful antimicrobial, anti-inflammatory, antioxidant and even antidepressant, anti-aging effects. The present review aims to provide an overview on anticancer activities of RA and to deliberate its therapeutic potential against a wide variety of diseases. Given the current evidence, RA may be considered as part of the daily diet in the treatment of several diseases, with pre-determined doses avoiding cytotoxicity.

Oregano (Origanum vulgare) extract for food preservation and improvement in gastrointestinal health

The Mediterranean diet has long been known to provide a variety of health benefits such as cardiovascular protection, cancer prevention, and lowering gastrointestinal inflammation. Oregano (Origanum vulgare) is an herb prominent in the Mediterranean diet, and has been shown to possess several bioactive properties including anti-oxidant, anti-microbial, anti-inflammatory, and analgesic properties. The anti-oxidant and anti-microbial properties of oregano also make it a strong candidate as a natural food preservative. Because of the recent public concern with synthetic food preservatives, natural alternatives are increasingly being evaluated for effective food preservation. Oregano extract (OE) and essential oil (OEO) are two such agents that have shown promise as natural food preservatives. Additionally, oregano is being evaluated for its positive effect on gastrointestinal health, suggesting an additional benefit of food preservation with oregano. This review will describe in vitro studies related to the anti-microbial and anti-oxidant properties of oregano along with food preservation studies with oregano in various model food matrices. The major phytochemical content reported for OE and OEO will also be outlined to highlight the importance of characterizing the extract that is used, since the extraction process can have a significant effect on the phytochemicals therein. Finally, in vivo studies that investigate the gastrointestinal health benefits of oregano, specifically against inflammation, will be addressed to show the impact of oregano on gastrointestinal health.

Hydroalcoholic extract from Origanum vulgare induces a combined anti-mycobacterial and anti-inflammatory response in innate immune cells

In nature, many plants or their extracted compounds have been found to possess anti-inflammatory features and therapeutic properties against infectious as well as non-infectious diseases, including cancer. In this study, we analysed the immunomodulatory effects on innate immune cells of hydroalcoholic extract from Origanum vulgare L. ssp. hirtum (HyE-Ov), a plant traditionally known for its anti-oxidative properties. The effects of HyE-Ov were tested on human monocyte derived dendritic cells (DC), type-1 (M1) and type-2 macrophages (M2) infected with M. bovis Bacille Calmette-Guérin (BCG), used as a model of persistent intracellular bacterium. DC, M1 and M2 treated with HyE-Ov significantly enhanced their mycobactericidal activity, which was associated with phagosomal acidification in M1 and M2 and increase of phagosomal, but not mitochondrial ROS production in M1, M2, and DC. Treatment of BCG-infected DC with HyE-Ov significantly reduced TNF-α and IL-12 production and increased TGF-β synthesis. Finally, experiments were repeated using eight different HPLC fractions of HyE-Ov. Results showed that the capability to activate anti-microbial and anti-inflammatory response is shared by different fractions, suggesting that diverse bioactive molecules are present within the hydroalcoholic extract. Altogether, these results show that HyE-Ov promotes anti-mycobacterial innate immunity and limits inflammatory response in vitro and suggest that this plant extract may be exploitable as phytocomplex or nutraceutical for novel host-directed therapeutic approaches.

Ethanolic Extract of Origanum vulgare Suppresses Propionibacterium acnes-Induced Inflammatory Responses in Human Monocyte and Mouse Ear Edema Models

Acne vulgaris (acne) is a common inflammatory skin disorder, and Propionibacterium acnes plays a major role in the development and progression of acne inflammation. Herbs possessing antimicrobial and anti-inflammatory activity have been applied as a medical option for centuries. In this study, we examined the suppressive effect of ethanolic oregano (Origanum vulgare) extract on live P. acnes-induced in vivo and in vitro inflammation. Following ethanol extraction of oregano leaves, four compounds with strong antioxidant activity, including rosmarinic acid, quercetin, apigenin, and carvacrol, were identified by high-performance liquid chromatography. Using the mouse ear edema model, we demonstrated that ethanol oregano extracts (EOE) significantly suppressed P. acnes-induced skin inflammation, as measured by ear thickness (32%) and biopsy weight (37%). In a separate study, using the co-culture of P. acnes and human THP-1 monocytes, EOE reduced the production of interleukin (IL)-8, IL-1β and tumor necrosis factor (TNF)-α up to 40%, 37%, and 18%, respectively, as well as the expression of these three pro-inflammatory mediators at the transcriptional level. Furthermore, EOE inhibited the translocation of nuclear factor-kappa B (NF-κB) into the nucleus possibly by inactivating toll-like receptor-2 (TLR2). The suppressive effect of EOE on live P. acnes-induced inflammatory responses could be due, in part, to the anti-inflammatory and antioxidant properties, but not the anti-microbial effect of EOE.

Interconnected PolymerS TeChnology (IPSTiC): An Effective Approach for the Modulation of 5α-Reductase Activity in Hair Loss Conditions

Hair loss represents a condition that adversely affects the social life of patients. The most common cause is androgenetic alopecia (AGA), which is a genetically determined progressive hair-loss condition involving 5α-reductase. In this study, a novel anti-baldness agent based on Interconnected PolymerS TeChnology (IPSTiC), which is an effective strategy for the delivery of bioactive molecules, was developed. This product (IPSTiC patch hair) is based on a polymeric blend consisting of high molecular weight hyaluronic acid and soybean proteins and is able to improve efficacy and stability of bioactive ingredients such as Origanum vulgare leaf extract, Camellia Sinensis leaf extract, and Capsicum Annuum fruit extract. The efficacy of the developed anti-baldness agent was investigated by performing several tests including NO radical and 5α-reductase inhibition assays, stability studies under different conditions, and in vitro diffusion studies using Franz cells. The biocompatibility of IPSTiC patch hair was also evaluated by in vitro analysis of the pro-sensitising potential and EPISKIN model. The obtained results confirmed both the efficacy and safety of IPSTiC patch hair supporting the potential use of this product in the topical treatment of AGA.

Origanum vulgare mediated green synthesis of biocompatible gold nanoparticles simultaneously possessing plasmonic, antioxidant and antimicrobial properties

Purpose

The leaves and flowering stem of Origanum vulgare contain essential oils, flavonoids, phenolic acids and anthocyanins. We propose a new, simple, one-pot, O. vulgare extract (OVE) mediated green synthesis method of biocompatible gold nanoparticles (AuNPs) possessing improved antioxidant, antimicrobial and plasmonic properties.

Materials and methods

Different concentrations of OVEs were used to reduce gold ions and to synthetize biocompatible spherical AuNPs. Their morphology and physical properties have been investigated by means of transmission electron microscopy, ultraviolet-visible absorption spectroscopy, photon correlation spectroscopy and Fourier transform infrared spectroscopy, whereas their plasmonic properties have been tested using surface-enhanced Raman spectroscopy (SERS). The antioxidant properties of nanoparticles (NPs) have been evaluated by 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay, and the antimicrobial tests were performed using the disk diffusion assay. Their cytotoxicity has been assessed by means of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.

Results

The experimental results confirmed the successful synthesis of biocompatible, spherical, plasmonic NPs having a mean diameter of ~40 nm and an outstanding aqueous stability. This new class of NPs exhibits a very good antioxidant activity and presents interesting inhibitory effects against Staphylococcus aureus and Candida albicans. Due to their plasmonic properties, AuNPs are used as SERS substrates for the detection of a test molecule (methylene blue) up to a concentration of 10^-7 M and a pharmaceutical compound (propranolol) in solution. Cytotoxicity assays revealed that AuNPs are better tolerated by normal human dermal fibroblast cells, while the melanoma cancer cells are more sensitive.

Conclusion

The biocompatible AuNPs synthetized using OVEs showed significant bactericidal and antimycotic activities, the most sensitive microorganisms being S. aureus and C. albicans, both commonly involved in various dermatological infections. Moreover, the significant antioxidant effect might recommend their use for protective and/or preventive effect in various skin inflammatory conditions, including the reduction in side effects in dermatological infections. Meanwhile, the as-synthesized biocompatible AuNPs can be successfully used as SERS substrates for the detection of pharmaceutical compounds in aqueous solutions.

Flavonoids and Phenolic Acids from Oregano: Occurrence, Biological Activity and Health Benefits

Several herb species classified as oregano have been widely used in folk medicine to alleviate inflammation-related diseases, respiratory and digestive disorders, headaches, rheumatism, diabetes and others. These potential health benefits are partially attributed to the phytochemical compounds in oregano such as flavonoids (FL) and phenolic acids (PA). Flavonoids and phenolic acids are among the most abundant and most studied phytochemicals in oregano species. Epidemiological, in vitro and in vivo experiments have related long-term consumption of dietary FL and PA with a decreased risk of incidence of chronic diseases. The aim of this manuscript is to summarize the latest studies on the identification and distribution of flavonoids and phenolic compounds from oregano species and their potential antioxidant, anti-inflammatory and anti-cancer health benefits.

Modulation of T Cell Activation in Obesity

SIGNIFICANCE

Immune T cells are present in adipose tissues (AT), and the stoichiometry of the different T cell subsets is altered during diet-induced obesity (DIO). T cells contribute to the early steps of AT inflammation during DIO. Recent Advances: Many factors could potentially be responsible for this altered pro-inflammatory versus anti-inflammatory T cell balance.

CRITICAL ISSUES

T cells are potentially activated in AT, which vitamin D might contribute to, as will be discussed in this article. In addition, we will review the different possible contributors to T cell activation in AT, such as the CD28 and CD154 T cell costimulatory molecules in AT.

FUTURE DIRECTIONS

The potential antigen presentation capacities of adipocytes should be further investigated. Moreover, the properties of these AT resident (or migrating to AT) T cells must be further assessed. Antioxid. Redox Signal. 26, 489-500.

Chamomile and oregano extracts synergistically exhibit antihyperglycemic, antihyperlipidemic, and renal protective effects in alloxan-induced diabetic rats

The bio-activities of separate Matricaria chamomilla (chamomile) and Origanum vulgare (oregano) are well studied; however, the combined effects of both natural products in animal diabetic models are not well characterized. In this study, alloxan-induced male albino rats were treated with single dose aqueous suspension of chamomile or oregano at dose level of either 150 or 300 mg/kg body mass or as equal parts as combination by stomach tube for 6 weeks. After treatment, blood samples were assessed for diabetic, renal, and lipid profiles. Insulin, amylase activity, and diabetic renal apoptosis were further evaluated. Treatment with higher dose of the extracts (300 mg/kg) as individual or as mixture of low doses (150 mg/kg of both the extracts) had significant mass gain, hypoglycemic effect (p ≤ 0.05) with decreased amylase activity and increased serum insulin levels. Restoration of renal profile, lipid profile with increase in HDL-c (p ≤ 0.05) along with reversal of pro-apoptotic Bax and anti-apoptotic Bcl-2 were well observed with 300 mg/kg mixture, showing synergistic activity of the extracts compared with individual low dose of 150 mg/kg. Collectively, our results indicate that combination of chamomile and oregano extracts will form a new class of drugs to treat diabetic complications.

Chemical and Biological Aspects of Extracts from Medicinal Plants with Antidiabetic Effects

Diabetes mellitus is a chronic disease and a leading cause of death in western countries. Despite advancements in the clinical management of the disease, it is not possible to control the late complications of diabetes. The main characteristic feature of diabetes is hyperglycemia, which reflects the deterioration in the use of glucose due to a faulty or poor response to insulin secretion. Alloxan and streptozotocin (STZ) are the chemical tools that are most commonly used to study the disease in rodents. Many plant species have been used in ethnopharmacology or to treat experimentally symptoms of this disease. When evaluated pharmacologically, most of the plants employed as antidiabetic substances have been shown to exhibit hypoglycemic and antihyperglycemic activities, and to contain chemical constituents that may be used as new antidiabetic agents. There are many substances extracted from plants that offer antidiabetic potential, whereas others may result in hypoglycemia as a side effect due to their toxicity, particularly their hepatotoxicity. In this article we present an updated overview of the studies on extracts from medicinal plants, relating the mechanisms of action by which these substances act and the natural principles of antidiabetic activity.

Deconvoluting the Dual Antiplatelet Activity of a Plant Extract

A thorough evaluation of the antiplatelet activity profile of hexane olive leaf extract in human platelets indicated a potent activity accomplished through a two axis inhibition of platelet activation triggered both by ADP and thrombin. To delineate the extract components responsible for this dual activity, an NMR based method was established to determine and quantify the triterpenoid content leading to the characterization of uvaol, erythrodiol, and oleanolic acid. The antiplatelet profile of the total extract and of the 3 determined triterpenoids was evaluated against in vitro platelet aggregation induced by several platelet agonists as also on PAC-1 binding and P-selectin membrane expression both in healthy volunteers and in platelets from patients with an acute coronary syndrome receiving dual antiplatelet therapy with aspirin and ticagrelor. The extract was identified to inhibit ADP-induced platelet activation due to its erythrodiol content and TRAP-induced platelet activation due to the activity of uvaol and oleanolic acid.

Ethyl Acetate Extract of Origanum vulgare L. ssp. hirtum Prevents Streptozotocin-Induced Diabetes in C57BL/6 Mice

Type 1 diabetes (T1D) is an autoimmune disease that develops as a consequence of pancreatic β-cell death induced by proinflammatory mediators. Because Origanum vulgare L. ssp. hirtum (Greek oregano) contains antiinflammatory molecules, we hypothesized that it might be beneficial for the treatment of T1D. An ethyl acetate extract of oregano (EAO) was prepared from the leaves by a polar extraction method. Phytochemical composition was determined by liquid chromatography-UV diode array coupled to ion-trap mass spectrometry with electrospray ionization interface (LC/DAD/ESI-MS(n) ). In vitro immunomodulatory effect of EAO was estimated by measuring proliferation (MTT) or cytokine secretion (ELISA) from immune cells. Diabetes was induced by multiple low doses of streptozotocin (MLDS) in male C57BL/6 mice and EAO was administered intraperitoneally for 10 d. Determination of cellular composition (flow cytometry) and cytokine production (ELISA) was performed on 12th d after diabetes induction. EAO suppressed the function of both macrophages and lymphocytes in vitro. In vivo, EAO treatment significantly preserved pancreatic islets and reduced diabetes incidence in MLDS-challenged mice. Besides down-modulatory effect on macrophages, EAO reduced the number of total CD4(+) and activated CD4(+) CD25(+) T cells. Furthermore, EAO affected the number of T helper 1 (Th1) and T helper 17 (Th17) cells through downregulation of their key transcription factors T-bet and RORγT. Because EAO treatment protects mice from development of hyperglycemia by reducing proinflammatory macrophage/Th1/Th17 response, this plant extract could represent a basis for future diabetes therapy.

Traditional management of diabetes in Pakistan: Ethnobotanical investigation from Traditional Health Practitioners

ETHNOPHARMACOLOGICAL RELEVANCE

The uses of anti-diabetic plants are well anchored in the traditional health care system of Pakistan. To the best of our knowledge, this is the first ethno-botanical study about the uses of plants for the treatment of diabetes. The aim of the study is to record indigenous knowledge on anti-diabetic plants from Traditional Health Practitioners (THPs) and diabetic patients. In addition, it is aimed to ascertain and validate the traditional uses of anti-diabetic plants by citing pharmacological activities and phytochemical constitutes from previously published literature.

MATERIALS AND METHODS

The ethno-medicinal data was documented during 14 field surveys, each comprising of 10 days, from 3 regions of Pakistan (Islamabad, Khyber Pukhtoonkhwa and Deserts of Sindh). In total, 113 THPs and 44 diabetic patients were interviewed using open-ended and semi-structured questionnaires. Quantitative indices, including Relative Frequency of Citation percentage (RFC %) and Disease Consensus Index (DCI) were calculated. The documented data is authenticated by comparing with 28 published articles on ethno-botanical aspects and many pharmacological studies.

RESULTS

In total, 120 plant species belonging to 50 families were reported. The ethno-botanical results indicated that Moraceae (11 species); herb (56 reports) is dominant life form; the leaves (56 reports) are the most used plant part and decoction (24%) is the preferred mode of preparation. The quantitative analysis shows that RFC% ranges from 14 to 42 and DCI varies from 0.15 to 0.74. By comparing to previous studies, 64 species are reported new in traditional treatment of DM; 40 species are new to pharmacological evidence and 3 species are new to phytochemical studies.

CONCLUSIONS

This study recoded the significant indigenous knowledge about anti-diabetic plants among the THPs and diabetic patients in Pakistan. This type of ethno-botanical knowledge on traditional use of anti-diabetic plants is an important step in designing detailed pharmacological and clinical trials for Diabetes Miletus treatment. It is recommended that further pharmacological and phytochemical analysis should be conducted on those species which lack previous references in literature and have highest Frequency of Citation (FC), Disease Consensus Index (DCI) and Relative Frequency of Citation percentage (RFC%).