Antiulcer activity of Mikania cordata

Regulation of anti-inflammatory and antioxidant responses by methanol extract of Mikania cordata (Burm. f.) B. L. Rob. leaves via the inactivation of NF-κB and MAPK signaling pathways and activation of Nrf2 in LPS-induced RAW 264.7 macrophages

Mikania cordata (Burm. f.) B.L. Rob. has been traditionally used in tropical countries throughout Asia and Africa to treat gastric ulcers, dyspepsia, and dysentery. However, the mechanisms responsible for its anti-inflammatory and antioxidant activities are not fully understood. Therefore, this study sought to investigate the anti-inflammatory and antioxidant effects of methanol extracts of M. cordata (MMC) on inflammation and oxidative stress in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages and elucidate its underlying regulatory mechanism. MMC significantly suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-stimulated RAW 264.7 macrophages by downregulating the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) at both the mRNA and protein levels. Moreover, MMC effectively reduced the mRNA expression levels and production of pro-inflammatory cytokines, including interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α). These suppressive effects of MMC on pro-inflammatory mediators and cytokines were mediated through the inhibition of transforming growth factor beta-activated kinase 1 (TAK1), which subsequently blocked the activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs). MMC also upregulated the nuclear factor erythroid-2-related factor 2 (Nrf2) by inducing the degradation of Kelch-like ECH-related protein 1 (Keap1), an Nrf2-specific E3 ligase. Accordingly, MMC enhanced Nrf2 target gene expression of anti-oxidative regulators such as heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1). However, it had minimal effect on the DPPH radical scavenging capacity in vitro. Collectively, these findings demonstrate that MMC holds promise as a potential therapeutic agent for alleviating inflammation-related diseases and oxidative stress.

In Vitro Determination of Antimicrobial and Hypoglycemic Activities of Mikania cordata (Asteraceae) Leaf Extracts

Infectious diseases and diabetes mellitus are counted responsible for a substantial amount of mortality among the human population. The current study was performed to detect the antimicrobial activities and hypoglycemic potential of Mikania cordata (Asteraceae) leaves extracted into aqueous media and several organic solvents (ethyl acetate and methanol). The ethyl acetate extract of Mikania cordata (MEA) leaves was observed to possess significantly ( $p\le 0.05$ ) greater antimicrobial capabilities (susceptible against Bacillus cereus ATCC 11778 and Staphylococcus aureus ATCC 25923) when compared with that of the methanol (MME) and aqueous extracts (MDW) which were assessed based on Kirby-Bauer disk diffusion assay. The minimum inhibitory concentration of MEA (against B. cereus, S. aureus, and Escherichia coli ATCC 25922) and MME (against B. cereus, S. aureus, E. coli, and Candida albicans ATCC 10231) lies in a similar range of 1.13 > MIC>0.56 mg/ml. In the present study, a single compound (from MEA) of Rf value 0.64 was isolated by thin-layer chromatography (TLC) that was responsible for the zone of inhibition against B. cereus (20.3 ± 0.3 mm). The results of this study also depicted the antihyperglycemic properties of M. cordata leaves which followed the same trend as the commercial drug Metformin in a glucose concentration-independent manner when tested in a glucose uptake assay by yeast cells. Therefore, it is evident that Mikania cordata is a reservoir of useful bioactive compounds which with further research will be paving the path for drug commercialization. This is the first record of TLC-based isolation of antimicrobial compounds of M. cordata and analysis of the hypoglycemic properties of M. cordata leaves.

Antimicrobial Activity of Cultivable Endophytic and Rhizosphere Fungi Associated with "Mile-a-Minute," Mikania cordata (Asteraceae)

Endophytic and rhizosphere fungi are understood to be aiding the host plant to overcome a range of biotic and abiotic stresses (nutrition depletion, droughts, etc.) hence, they remain to be reservoirs of plethora of natural products with immense use. Consequently, this investigation of endophytic and rhizosphere fungi isolated from Mikania cordata (a perennial vine that is well established in Sri Lanka) for their antimicrobial properties was performed with the aim of future derivation of potential beneficial pharmaceutical products. Leaves, twigs, and roots of M. cordata were utilized to isolate a total of 9 endophytic fungi out of which the highest amount (44%) accounted was from the twigs. A sample of the immediate layer of soil adhering to the root of M. cordata was utilized to isolate 15 rhizosphere fungi. Fusarium equiseti and Phoma medicaginis were endophytes that were identified based on colony and molecular characteristics. The broad spectrum of antimicrobial activity depicted by F. equiseti (MK517551) was found to be significantly greater (p ≤ 0.05, inhibitory against Bacillus cereus ATCC 11778, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 25853) than P. medicaginis (MK517550) (inhibitory against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 25853) as assessed using the Kirby-Bauer disk diffusion method. Trichoderma virens and Trichoderma asperellum were rhizospere fungi that exhibited remarkable antimicrobial properties against the test pathogens chosen for the study. T. asperellum indicated significantly greater bioactivity against all four bacterial pathogens and Candida albicans ATCC 10231 under study. The ranges of minimum inhibitory concentrations (MICs) of the fungi depicting antimicrobial properties were determined. The results obtained suggest that F. equiseti, P. medicaginis, T. asperellum, and T. virens of M. cordata harness bioprospective values as natural drug candidates. This is the first report on isolation and evaluation of the antimicrobial properties of endophytic and rhizosphere fungi of Mikania cordata.

Potential Antiulcer Agents From Plants: A Comprehensive Review

Background:

Peptic ulcer is a deep gastrointestinal erosion disorder that involves the entire mucosal thickness and can even penetrate the muscular mucosa. Nowadays, several plants and compounds derived from it have been screened for their antiulcer activity. In the last few years, there has been an exponential growth in the field of herbal medicine. This field has gained popularity in both developing and developed countries because of their natural origin and less side effects.

Objective:

This review aims to provide a comprehensive summary of currently available knowledge of medicinal plants and phytoconstituents reported for their anti-ulcer properties.

Methods:

The worldwide accepted database like SCOPUS, PUBMED, SCIELO, NISCAIR, ScienceDirect, Springerlink, Web of Science, Wiley, SciFinder and Google Scholar were used to retrieve available published literature.

Results:

A comprehensive review of the present paper is an attempt to list the plants with antiulcer activity. The review narrates the dire need to explore potential chemical moieties that exert an antiulcer effect, from unexploited traditional plants. Furthermore, the present study reveals the intense requirement to exploit the exact mechanism through which either the plant extracts or their active constituents exhibit their antiulcer properties.

Conclusion:

This article is the compilation of the plants and its constituents reported for the treatment of peptic ulcers. The Comprehensive data will surely attract the number of investigators to initiate further research that might lead to the drugs for the treatment of ulcers. As sufficient scientific data is not available on plants, most of the herbals cannot be recommended for the treatment of diseases. This can be achieved by research on pure chemical structures derived from plants or to prepare new lead compounds with proven beneficial preclinical in vitro and in vivo effects. However, a lot remains to be done in further investigations for the better status of medicinal plants.

Survey and scientific evaluation of medicinal plants used by the Pahan and Teli tribal communities of Natore district, Bangladesh

The Pahans and the Telis are two of the smallest indigenous communities in Bangladesh. The Pahans, numbering about 14,000 people are widely scattered in several northern districts of the country, while the Telis are such a small community that nothing has been reported on their numbers and lifestyle. Both tribes are on the verge of disappearance. One each of the Pahan and the Teli community was located after much search in two adjoining villages of Natore district, Bangladesh. Since the tribes were found to still depend on their traditional medicinal practitioners for treatment of ailments, it was the objective of the present study to document their traditional usage of medicinal plants and to evaluate such plants against modern research-based pharmacological activity studies on these plants. Interviews were conducted of the practitioners of the Pahan and Teli community of Natore district with the help of a semi-structured questionnaire and using the guided field-walk method. Plant specimens as pointed out by the practitioners were collected and pressed on the field and identification completed at the Bangladesh National Herbarium. The Pahan tribal practitioners used 13 plants distributed into 9 families for treatment of 14 different ailments. The Teli tribal practitioner used 15 plants divided into 14 families for treatment of 17 different ailments. Eight out of the thirteen plants used by the Pahan tribal practitioner (61.5%) had reported relevant pharmacological activities in the scientific literature, while six out of the fifteen plants used by the Teli tribal practitioners (40%) had such relevant pharmacological activities in accordance with their usage. The medicinal plants used by the Pahans and Telis warrant further scientific studies toward discovery of lead compounds and efficacious drugs and the documentation and protection of the traditional medical knowledge held by these tribes.

Gastroprotection and effect of the simultaneous administration of Cuachalalate (Amphipterygium adstringens) on the pharmacokinetics and anti-inflammatory activity of diclofenac in rats

This work aimed to study the effect of Cuachalalate methanol extract (CME) on the anti-inflammatory activity and pharmacokinetics of diclofenac sodium, a frequently prescribed non-steroidal antiinflammatory drug (NSAID). The gastroprotective effect of CME on the gastric injury induced by diclofenac was studied in rats. CME showed a gastroprotective effect of 15.7% at 1 mg kg−1 and 72.5% at dose of 300 mg kg−1. Omeprazole, used as anti-ulcer reference drug, showed gastroprotective effects of 50–89.7% at doses tested (1–30 mg kg−1). The value of the 50% effective dose for the anti-inflammatory effect of diclofenac sodium (ED50 = 1.14 ± 0.23 mg kg−1) using carrageenaninduced rat paw oedema model, was not modified by the concomitant administration of 30 or 100 mg kg−1 of CME. The effect of CME (30, 100 and 300 mg kg−1, p.o.) on the pharmacokinetics of diclofenac sodium was studied. It was observed that the simultaneous administration of diclofenac sodium and 300 mg kg−1 of CME decreased significantly the values of Cmax (7.08 ± 1.42 μg mL−1) and AUC (12.67 ± 2.97 μg h mL−1), but not the value of tmax (0.13 (0.1–0.25) h) obtained with the administration of diclofenac alone. The simultaneous administration of 30 or 100 mg kg−1 of CME did not modify the pharmacokinetic parameters of diclofenac. The experimental findings in rats suggest that CME at doses lower than 100 mg kg−1 protects the gastric mucosa from the damage induced by diclofenac sodium without altering either the anti-inflammatory activity or the pharmacokinetics of this NSAID.

Antiviral constituents against respiratory viruses from Mikania micrantha

Phytochemical investigation of the dried aerial parts of Mikania micrantha led to the isolation of a new sesquiterpene, 3beta-acetoxy-1,10-epoxy-4-germacrene-12,8;15,6-diolide (1), along with six known constituents: 1,10-epoxy-4-germacrene-12,8;15,6-diolide (2), dihydromikanolide (3), potassium mikanin 3-sulfate (4), mikanin (5), alpinetin (6), and ergosta-7,22-dien-3beta-ol (7). Their structures were elucidated by spectroscopic methods, and the molecular structures and stereochemistry of sesquiterpene lactones 1-3 were revealed by single-crystal X-ray analysis. Compound 2 showed moderate activity against respiratory syncytial virus (IC(50) = 37.4 uM) and parainfluenza type 3 virus (IC(50) = 37.4 uM) with a therapeutic index (TI) of 16.0 for both compounds. Compound 4, the main component of M. micrantha, exhibited inhibitory activity against parainfluenza type 3 virus with IC(50) (19.7 uM) and TI (24.0) values comparable to those of ribavirin, serving as a positive control.

Effects of Mikania genus plants on growth and cell adherence of mutans streptococci

The present study evaluated the chemical composition and the antimicrobial activity of the extracts and fractions of Mikania laevigata and Mikania glomerata on growth and cell adherence of mutans streptococci. Ethanolic extract, hexane and ethyl acetate fractions of Mikania laevigata and Mikania glomerata were chemically identified by chromatographic methods and tested on mutans streptococci from culture collection and clinical isolates. Twenty-two compounds were identified in both Mikania extracts, including coumarin, 1-octadecene, and diterpenic, cupressenic and kaurenoic acids. Antimicrobial activity was assessed by determination of the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and inhibition of cell adherence to a glass surface. Hexane fraction from both plant extracts was the most effective in inhibiting the growth of the bacterial strains tested (MIC values between 12.5 microg/ml and 400 microg/ml, and MBC values between 25 microg/ml and 400 microg/ml). In addition, sub-MIC levels of the crude extracts and their hexane fractions significantly inhibited the adherence of the microorganisms to a glass surface. The data indicate that the biologically active compounds are present mostly in the hexane fraction of both Mikania species, which showed remarkable inhibitory activities against mutans streptococci. Mikania genus plant is a promising source for novel antimicrobial agents against oral pathogens.

Antiulcerogenic activity of a crude hydroalcoholic extract and coumarin isolated from Mikania laevigata Schultz Bip

The leaves of Mikania (Asteraceae) species are used in folk medicine as antispasmodic, antiulcerogenic and antirheumatic agents. Phytochemical screening of the crude hydroalcoholic 70% extract (CHE) of Mikania laevigata Shultz Bip. revealed coumarins, terpenes and organic acids. Antiulcerogenic activity of CHE was evaluated, employing different experimental models in rats, to discern the pharmacological mechanism of action. Both the antisecretory and the cytoprotection hypothesis were evaluated. The crude hydroalcoholic extract (1000 mg/kg body wt., vo) decreased the ulcerative lesion index produced by indomethacin, ethanol, stress and reserpine in rats by 85%, 93%, 82% and 50%, respectively. In the pyloric ligation model, a decrease of hydrogenionic concentration (53%) was observed, suggesting that the pharmacological mechanism has a relationship to antisecretory activity. The antisecretory mechanisms of CHE and the coumarin isolated from M. laevigata were confirmed by acid hypersecretion induced by histamine, pentagastrin and bethanechol. Duodenal administration of CHE (1000 mg/kg body wt.) and coumarin (100 mg/kg body wt.) inhibited only the gastric acid secretion produced by bethanecol. These results suggest that both CHE and coumarin may influence the secretion control mediated by the parasympathetic system.

Analgesic sesquiterpene dilactone from Mikania cordata

The crude extract of Mikania cordata (1 and 3 g/kg, p.o.) and deoxymikanolide (1) (10 mg/kg, p.o.) significantly inhibited acetic acid-induced writhing in mice. Three other sesquiterpene dilactones isolated from the same plant, namely mikanolide, dihydromikanolide and scandenolide, did not show significant analgesic activity.