Anti-inflammatory potential of thienopyridines as possible alternative to NSAIDs.

The present study was designed to evaluate the anti-inflammatory and antiarthritic activity of the new synthetic thienopyridine analogs. The anti-inflammatory activity of thienopyridines was assayed by using carrageenan; dextran and arachidonic acid induced paw edema models (acute), cotton pellet granuloma model (Sub acute) and Freund's complete adjuvant induced arthritis (chronic) in experimental rats. The compounds BN-4, BN-14 and BN-16 have shown significant inhibition of edema in carrageenan and arachidonic acid induced paw edema model at a dose of 100mg/kg compared to the dextran induced paw edema model and also showed significant inhibition in granuloma tissue formation and Freund's complete adjuvant induced arthritis in experimental rats. These thienopyridine analogs also inhibited the proinflammatory mediators such as Tumor necrosis factor (TNF)-α, Interleukin (IL)-1ß and Nitric Oxide (NO) in Lipopolysaccharide (LPS) challenged murine macrophages. Ulcerogenecity study results revealed less ulcerogenic potential of BN-4, BN-14 and BN-16 compared to nonsteroidal anti-inflammatory drug (NSAID) indomethacin in rats. In conclusion, the new thienopyridine analogs were promising for the potential use as anti-inflammatory agents for both acute and chronic inflammatory disorders with low toxic effects.

Neuroprotective effect of Alpinia galanga (L.) fractions on Aß(25-35) induced amnesia in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: The rhizomes of Alpinia galanga (L.) Willd (Zingiberaceae), a ginger substitute for flavouring food was traditionally used as nervine tonic and stimulant. AIM OF THE STUDY: This investigation is designed to screen cognitive improvement of Alpinia galanga (AG) fractions in Alzheimer's type of amnesia in mice induced by Aß((25-35)). MATERIALS AND METHODS: Alzheimer's disease induced mice treated with fractions (n-hexane, chloroform and ethyl acetate) of AG in 200 and 400mg/kg. Neurotoxicity was induced by intracerebroventricular injection of Aß((25-35)) on the 14th day of 21 days drug treatment. Open field and water maze were carried to determine habituation memory and hippocampal memory. Na(+)/K(+)-ATPase, acetylcholinesterase (AChE) and antioxidant enzymes (SOD, GPx, catalase and vitamin C) were determined in brain tissue homogenate to estimate the brain biochemical changes and its anti-amnesic potential with intensity of oxidative stress signaling. Further bioactive (chloroform) fraction was eluted through column chromatography to identify the lead molecules. RESULTS: Increased habituation memory and decreased escape latency in behavioral parameter are the indicative of the cognitive enhancement after treatment with Alpinia galanga fractions. Increment in Na(+)/K(+)-ATPase and antioxidant activity depicts brain membrane integrity improvement and free radical scavenging property. AChE level was decreased to improve the cognition by enhancing cholinergic transmission. CONCLUSION: Anti-amnesic effect was exerted by various fractions of Alpinia galanga. Among all fractions, preeminent neuroprotection was exerted by chloroform fraction, which has compound, 1'δ-1'-acetoxyeugenol acetate and it may be a potential therapeutic agent for Alzheimer's type of amnesia. These results further motivate us to explore the activity of lead compound's anti-amnesic effect on transgenic mice model of AD.

Potential in vitro antioxidant and protective effects of Soymida febrifuga on ethanol induced oxidative damage in HepG2 cells.

There is increasing evidence that oxidative stress is implicated in pathogenesis of various diseases, including alcoholic liver injury. In the present study, we investigated the comparative protective effects of leaf, bark, root and root bark extracts of Soymida febrifuga (Roxb.) A. Juss. (Meliaceae) against ethanol induced oxidative damage in HepG2 cells. Comparatively, methanolic and aqueous extracts of bark and leaf significantly attenuated the cytotoxicity of the ethanol, as determined by cytotoxicity, lipid peroxidation, lactate dehydrogenase, alanine aminotransferases and asparatate aminotransferases, than the root and root bark extracts. Ethanol induces liver toxicity through free radical generation so initially in vitro antioxidant activity of the extracts was evaluated. Methanolic and aqueous extracts of bark and leaf have shown higher total phenolic content, reducing power, metal chelating, superoxide, hydroxyl radical, hydrogen peroxide and nitric oxide (murine macrophage cells) scavenging activity than the root and root bark extracts.

Evaluation of antioxidant and antimicrobial properties of Soymida febrifuga leaf extracts.

The present study was designed to evaluate the antioxidant and antimicrobial properties of hexane (LH), methanol (LM) and aqueous (LA) extracts of Soymida febrifuga (Maliaceae) leaves, which is a traditional folk medicine in India. No pharmacological evaluation of this plant (except antiplasmodial activity) has been reported to date. Antioxidant activity of different extracts was evaluated by DPPH free radical scavenging activity, taking total phenolic content (TPC) as an index. Antimicrobial activity was tested against six bacterial and five fungal strains using the agar hole diffusion method and the minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) were determined for all the test organisms against the extracts. The results showed that the methanol and aqueous extracts of leaf had a higher antioxidant activity and total phenolic content than the hexane extract. The antioxidant activity and TPC of the extracts were highly correlated. Extracts also showed several degrees of antimicrobial activity against different microbes. The methanol extract was more potent against Aspergillus fumigatus and Candida tropicana. The lowest MIC values obtained for LM, LA and LH were 78, 156, 625 microg/mL against A. fumigatus, C. tropicana and C. albicans, respectively. Hence, this study confirms that Soymida febrifuga leaves possess potent antioxidant and antimicrobial activity.

Evaluation of antimicrobial, antioxidant and wound-healing potentials of Holoptelea integrifolia.

The methanolic extracts of Holoptelea integrifolia (Roxb.) (Urticaceae) leaves (MLE) and stem bark (MSBE) were studied for the wound-healing potential. Since wound healing is severely hampered by microbial infection and reactive oxygen species (ROS), this study was undertaken to evaluate antimicrobial and antioxidant activity apart from wound-healing activity. The antimicrobial property of the Holoptelea was studied against the six bacterial and five fungal strains using the agar well diffusion method and minimum microbicidal concentration and minimum inhibitory concentration were determined for each strain, in which methanolic extract of stem bark (MSBE) has shown bigger zone of inhibition (11.3-20.4 mm) than methanolic extract of leaves (MLE) (9.6-14.9 mm). The anti-oxidant activity was evaluated by DPPH free radical scavenging activity using HPLC method. The IC(50) values obtained for MSBE (TPC: 78.53+/-1.26 mg/g) and MLE (TPC: 57.71+/-1.45 mg/g) were 37.66+/-0.48 and 50.36+/-0.59 microg/well, respectively. In excision wound model, more than 90% wound healing was recorded in treated groups by 14 days of post surgery, where as only 62.99% was observed in the control group. In incision model, higher breaking strengths and higher hydroxyproline content in treated groups suggested higher collagen re-deposition than the control group. Finally, histopathology studies conformed wound-healing activity of Holoptelea integrifolia.

Folate coupled poly(ethyleneglycol) conjugates of anionic poly(amidoamine) dendrimer for inflammatory tissue specific drug delivery.

Folate receptor is overexpressed on the activated (but not quiescent) macrophages in both animal models and human patients with naturally occurring rheumatoid arthritis. The aim of this study was to prepare folate targeted poly(ethylene glycol) (PEG) conjugates of anionic dendrimer (G3.5 PAMAM) as targeted drug delivery systems to inflammation and to investigate its biodistribution pattern in arthritic rats. Folate-PEG-PAMAM conjugates, with different degrees of substitution were synthesized by a two-step reaction through a carbodiimide-mediated coupling reaction and loaded with indomethacin. Folate-PEG conjugation increased the drug loading efficiency by 10- to 20-fold and the in vitro release profile indicated controlled release of drug. The plasma pharmacokinetic parameters indicated an increased AUC, circulatory half-life and mean residence time for the folate-PEG conjugates. The tissue distribution studies revealed significantly lesser uptake by stomach for the folate-PEG conjugates, thereby limiting gastric-related side effect. The time-averaged relative drug exposure (r(e)) of the drug in paw for the folate-PEG conjugates ranged from 1.81 to 2.37. The overall drug targeting efficiency (T(e)) was highest for folate-PEG conjugate (3.44) when compared to native dendrimer (1.72). The folate-PEG-PAMAM conjugates are the ideal choice for targeted delivery of antiarthritic drugs to inflammation with reduced side-effects and higher targeting efficiency.

The development of folate-PAMAM dendrimer conjugates for targeted delivery of anti-arthritic drugs and their pharmacokinetics and biodistribution in arthritic rats.

The aim of this study was to synthesize folate-dendrimer conjugates as suitable vehicle for site specific delivery of anti-arthritic drug (indomethacin) to inflammatory regions and to determine its targeting efficiency, biodistribution in adjuvant induced arthritic rats. Folic acid was coupled to the surface amino groups of G4-PAMAM dendrimer (G4D) via a carbodiimide reaction and loaded with indomethacin. The conjugates were characterized by (1)H-NMR and IR spectroscopy. The drug content and percent encapsulation efficiency increased with increasing folate content for the dendrimer conjugates. The in vitro release rate was decreased for the folate conjugates when compared with unconjugated dendrimer (DNI). The plasma concentration profile showed a biphasic curve indicating rapid distribution followed by slow elimination. The AUC(0-infinity), half-life and residence time of indomethacin in inflamed paw was higher for folate-dendrimer conjugates. The time-averaged relative drug exposure (r(e)) of the drug in paw and overall drug targeting efficiency (T(e)) were higher for folate conjugate with 21 folate moieties (4.1 and 2.78, respectively) when compared with DNI (1.91 and 1.88, respectively). This study demonstrated the superiority of active targeting over dendrimer mediated passive targeting and also for the first time, folate-mediated targeting of an anti-arthritic drug to the inflammatory tissues.

Determination of DPPH free radical scavenging activity by reversed-phase HPLC: a sensitive screening method for polyherbal formulations.

The colorimetric method of evaluation of antioxidant activity by scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical is with certain shortcomings like failure to indicate antioxidant activity of certain drugs and interference from color pigments of natural products. A specific HPLC method was developed for evaluating the DPPH free radical scavenging activity of commercial polyherbal formulations using a LiChrospher 100 RP-18e column (250 mm x 4 mm, 5 microM). The mobile phase was a mixture of methanol and water (80:20, v/v) pumped at a flow rate of 1 mL/min. The DPPH peaks were monitored at 517 nm. The method was standardized using known antioxidants such as ascorbic acid, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox), probucol and alpha-tocopherol. The 50% radical scavenging activity (IC50) determined by the HPLC method correlated well with that of colorimetry. This HPLC method was applied for the estimation of free radical scavenging activity of Silymarin and a few commercial hepatoprotective polyherbal formulations. While the colorimetric method failed to estimate the free radical scavenging activity of polyherbal formulations, HPLC method was free from interferences and was specific. The HPLC method is sensitive and can be used as a quality control tool for the rapid determination of free radical scavenging activity of variety of products including plant extracts, foods, drugs and polyherbal formulations.