Free radical scavenging and anti-inflammatory properties of <Emphasis Type="Italic">Lagerstroemia speciosa</Emphasis> (L)

The in vitro antioxidant activity of the successive extracts (ethyl acetate, ethanol, methanol and water) of the leaves of Lagerstroemia speciosa L. (Lythraceae) were studied by examining their superoxide, hydroxyl ion scavenging and by measuring lipid peroxidation. The ethyl acetate and ethanol extracts were found to possess greater antioxidant property than the methanol and water extracts. Anti-inflammatory activity of the ethyl acetate and ethanol extracts were examined using the carrageenan-induced acute inflammation and formalin-induced (chronic) paw edema models. In acute and chronic inflammation models, the ethyl acetate extract reduced the paw edema significantly in a dose-dependent manner. Whereas, ethanol extract did not show dose-dependent activity. This results suggests that the anti-inflammatory activity is possibly attributed to its free radical scavenging activity. It was found that ethyl acetate extract reduced the inflammation more significantly than the ethanol extract.     

Naproxen-PC: A GI safe and highly effective anti-inflammatory

We have been developing a family of phosphatidylcholine (PC)-associated NSAIDs, which appear to have improved GI safety and therapeutic efficacy in both rodent model systems and pilot clinical trials. As naproxen has been demonstrated to be associated with the lowest cardiovascular adverse events in comparison with both COX-2 selective inhibitors and conventional NSAIDs, we have been developing a Naproxen-PC formulation for evaluation in animal models and clinical trials. We have determined that an oil-based formulation of naproxen and triple strength soy lecithin provides excellent GI protection in both: 1) an acute NSAID-induced intestinal bleeding model in rats pretreated with L-NAME that are intragastrically administered a single dose of naproxen (at a dose of 50 mg/kg) vs the equivalent dose of Naproxen-PC; and 2) a more chronic model (at a naproxen dose of 25 mg/kg BID) in rats that have pre-existing hindpaw inflammation (induced with a intradermal injection of Complete Freund’s Adjuvant/CFA). Both models demonstrate the superior GI safety of Naproxen-PC vs naproxen while this novel formulation had significant anti-inflammatory efficacy to reduce hindpaw edema and the generation of PGE₂ in the collected joint synovial fluid. Conclusion: Naproxen-PC appears to induce significantly less GI injury and bleeding in two rodent model systems while maintaining anti-inflammatory and COX-inhibitory activity. Received 13 October 2008; accepted 11 November 2008     

Human whole blood assay for rapid and routine testing of non-steroidal anti-inflammatory drugs (NSAIDs) on cyclo-oxygenase-2 activity

Aim of this study was to present a simple, fast and reliable method to examine the capacity of NSAIDs to inhibiting COX-2 activity that uses rapid (stimulation takes only 5 h compared to other existing protocols) and routine testing. The assay includes elimination of COX-1-activity using ASS (a selective COX-1 inhibitor) and the thromboxane synthetase inhibitor (TXBSI), COX-2 induction via LPS and measurement of PGE(2). Using TXBSI reduces the amount of LPS and results in higher prostaglandin production.Cremophor EL((R))-EtOH was used as vehicle instead of DMSO because within a defined concentration range, Cremophor EL((R))-EtOH allows even very hydrophobic drugs to be solubilized and applied in vitro without cell damage. Cremophor EL((R))-EtOH at 0.2% was optimal as at this relatively low concentration excellent drug dissolution was obtained whereas many hydrophobic substances precipitate in 0.2% DMSO.Our results demonstrate that the IC(50) values for the tested NSAIDs are in the range of published data.     

Synthesis and reactions of some pyridazine derivatives

3,4-Diphenyl-5-cyanopyridazin-6-one 3 was prepared from the reaction of cyano-acetamide2 with benzilhydrazone in dry pyridine. A series of its derivatives was prepared. Tolyl and benzene sulphonyl derivatives6a and6b are also prepared. 3,4-Diphenyl-5-cyano-pyridazin-6-thione5 was obtained from3 by the action of P₂S₅ while 3,4-diphenyl-5-cyano-6-chloropyridazine4 was obtained from3 by the action of POCl₃. The reaction of4 with hydrazine hydrate directly afforded the pyrazolopyridazine derivative7. Compound4 also reacted with phenylhydrazine, aniline, thiophenol and anthranilic acid to yield pyridazine derivatives8, 9, 10 and11, respectively. On treatment of compound11 with acetic anhydride it cyclised to afford pyridazino pyrimidine derivatives12.     

Anti-oxidative and anti-inflammatory activities of some isolated constituents from the stem bark of Allanblackia monticola Staner L.C (Guttiferae)

Stem bark of Allanblackia monticola has been used in association with others plant in the Cameroonian folk medicine for the treatment of various diseases such amoebic dysentery, diarrhoea, lung infections, and skin diseases. The methylene chloride fraction, its isolated compounds like α-mangostin, lupeol and acid betulinic were screened for antioxidant activity using free radical scavenging method. These isolated compounds were further tested for anti-inflammatory properties using carrageenan-induced model. Methylene chloride fraction, showed concentration-dependent radical scavenging activity, by inhibiting 1,1-diphenyl-1-picryl-hydrazyl radical (DPPH) with an IC₅₀ value of 14.60 μg/ml. α-Mangostin and betulinic acid (500 μg/ml), showed weak radical scavenging activity with a maximum inhibition reaching 38.07 μg/ml and 26.38 μg/ml, respectively. Betulinic acid, lupeol and α-mangostin (5 mg/kg and 9.37 mg/kg) showed anti-inflammatory activity with a maximum inhibition of 57.89%, 57.14% and 38.70%, respectively. Methylene chloride fraction of Allanblackia monticola and some derivatives, have antioxidant and anti-inflammatory activities. Received 7 July 2008; accepted 7 October 2008     

The lathyrus toxin, beta-N-oxalyl-L-alpha,beta-diaminopropionic acid (ODAP), and homocysteic acid sensitize CA1 pyramidal neurons to cystine and L-2-amino-6-phosphonohexanoic acid

A brief exposure of hippocampal slices to L-quisqualic acid (QUIS) sensitizes CA1 pyramidal neurons 30- to 250-fold to depolarization by certain excitatory amino acids analogues, e.g., L-2-amino-6-phosphonohexanoic acid (L-AP6), and by the endogenous compound, L-cystine. This phenomenon has been termed QUIS sensitization. A mechanism similar to that previously described for QUIS neurotoxicity has been proposed to describe QUIS sensitization. Specifically, QUIS has been shown to be sequestered into GABAergic interneurons by the System x(c)(-) and subsequently released by heteroexchange with cystine or L-AP6, resulting in activation of non-NMDA receptors. We now report two additional neurotoxins, the Lathyrus excitotoxin, beta-N-oxalyl-L-alpha,beta-diaminopropionic acid (ODAP), and the endogenous compound, L-homocysteic acid (HCA), sensitize CA1 hippocampal neurons >50-fold to L-AP6 and >10-fold to cystine in a manner similar to QUIS. While the cystine- or L-AP6-mediated depolarization can be inhibited by the non-NMDA receptor antagonist CNQX in ODAP- or QUIS-sensitized slices, the NMDA antagonist D-AP5 inhibits depolarization by cystine or L-AP6 in HCA-sensitized slices. Thus, HCA is the first identified NMDA agonist that induces phosphonate or cystine sensitization. Like QUIS sensitization, the sensitization evoked by either ODAP or HCA can be reversed by a subsequent exposure to 2 mM alpha-aminoadipic acid. Finally, we have demonstrated that there is a correlation between the potency of inducers for triggering phosphonate or cystine sensitivity and their affinities for System x(c)(-) and either the non-NMDA or NMDA receptor. Thus, the results of this study support our previous model of QUIS sensitization and have important implications for the mechanisms of neurotoxicity, neurolathyrism and hyperhomocystinemia.     

Anti-Inflammatory Activity of Parthenolide-Depleted Feverfew (Tanacetum parthenium)

Extracts of Tanacetum parthenium (L.) Sch. Bip., a plant known under the common name “Feverfew”, contains the sesquiterpene lactone parthenolide, a potent skin sensitizer. To eliminate the risk of skin sensitization from Feverfew, we developed a parthenolide-depleted extract of Feverfew (PD-Feverfew) and determined its effectiveness as an anti-inflammatory agent. We confirmed that PD-Feverfew was sufficiently depleted of parthenolide since PD-Feverfew did not inhibit TNF-α induced-NF-κB activity unlike parthenolide containing whole Feverfew. PD-Feverfew directly inhibited the activity of pro-inflammatory enzymes 5-lipoxygenase, phosphodiesterase-3 and phosphodiesterase-4. PD-Feverfew inhibited the release of pro-inflammatory mediators nitric oxide, PGE₂ and TNF-α from macrophages and TNF-α, IL-2, IFN-γ and IL-4 from human peripheral blood mononuclear cells. Additionally, PD-Feverfew inhibited TPA-induced release of PGE₂ from human skin equivalents. In vivo, PD-Feverfew inhibited oxazolone-induced dermatitis, and was more potent than whole Feverfew in reducing TPA-induced dermatitis. Finally the efficacy of PD-Feverfew was confirmed clinically by a reduction in erythema in a methyl nicotinate-induced vasodilation model. In conclusion, our results indicate that PD-Feverfew extracts have potent anti-inflammatory activity suggesting that this botanical would be efficacious in relieving inflammation without inducing immune sensitization.     

Protective effect of polysaccharides from Angelica sinensis on ulcerative colitis in rats

Ulcerative colitis (UC) involves the dysregulation of intestinal mucosal immunity and imbalance between the reactive oxygen species (ROS) and the endogenous anti-oxidants. While the protective effects of Angelica sinensis (AS) polysaccharides on neutrophil-dependent gastric mucosal damage have been reported, similar protective effects on UC are still uncertain. Hence our study aimed to investigate the effects of AS polysaccharides on rats with acute UC induced by 2,4-dinitrobenzene sulphonic acid (DNBS) evaluated after 24 h. Intrarectal injection of DNBS significantly reduced the glutathione (GSH) content, increased malondialdehyde concentration and raised the amount of apoptotic cells in colon tissues, which were related to oxidative stress and attenuated by AS polysaccharides pretreatment (5 mg/ml and 10 mg/ml). These findings suggest that oxidative stress and GSH depletion are highly associated with the pathological mechanism of UC, and the protective effects of AS polysaccharides are closely related to the prevention of oxidative stress, which may occur during neutrophil infiltration in the pathological process of UC.     

Phospholipids fromBombycis corpus and their neurotrophic effects

Three phospholipids (4-6) and three aromatic amines (1-3) were obtained from the methanol extract of Bombycis corpus. Based on spectral data, their structures have been elucidated as nicotiamide (1), cytidine (2), adenine (3), 1-O-(9Z-octadecenoyl)-2-O-(8Z,11Z-octadecadienoyl) sn-glycero-3-phosphorylcholine (4), 1,2-di-O-hexadecanoyl-sn-glycero-3-phosphorylcholine (5) and 1,2-di-O-9Z-octadecenoyl-sn-glycero-3-phosphorylcholine (6). We examined the effects of compounds on synthesis of NGF in cultured astrocytes. By RT-PCR analysis, expresison of NGF mRNA in astrocytes cultured in serum-starvation increased after the addition of phospholipid (10 microM). The NGF content in the culture medium was significantly increased by compound 5, compared with the control value. These results suggest that three phospholipid compounds isolated from the methanol extract of Bombycis corpus may exert neurotrophic effects by stimulation of NGF synthesis in astrocytes.     

Bioactive effects of olive oil phenolic compounds in humans: reduction of heart disease factors and oxidative damage

Oxidative stress is defined as an imbalance between the oxidant and antioxidant systems of the body, in favour of the oxidants. Oxidative stress produced by free radicals has been linked to the development of several diseases such as cardiovascular, cancer, and neurodegenerative diseases. Olive oil is the main source of fat of the Mediterranean diet which has been shown to be effective against oxidative stress associated diseases and also with the ageing. Besides its richness in monounsaturated fatty acid, the oleic acid, olive oil contains minor components with antioxidant properties. Here, we update the state of the art, and degree of evidence, of the body of knowledge concerning the protective role on lipids and lipid oxidative damage in humans of the olive oil phenolic compounds.     

Methanolic extract of Ruta graveolens L. inhibits inflammation and oxidative stress in adjuvant induced model of arthritis in rats

Ruta graveolens L. (Rutaceae) are traditionally used for the treatment of rheumatism, arthritis and other inflammatory conditions in the traditional medicine of India. The purpose of this study was to investigate anti-inflammatory and anti-oxidant effects of methanolic extract of Ruta graveolens L. in adjuvant induced arthritis in rats. Methanolic extract of Ruta graveolens (MER) exhibited maximum percentage of oedema inhibition at a dose of 20 mg/kg on 21st day of adjuvant arthritis. The effect was higher than that of standard drug indomethacin. The activities of cycloxygenase-2 and myeloperoxidase and concentration of thiobarbituric acid reactive substance (TBARS) were decreased and the activities of antioxidant enzymes, vitamins C & E and reduced glutathione level were increased on treatment with MER. The increment in ESR and total WBC, reduction in RBC count and haemoglobin and aberrant changes to the C-reactive protein (CRP) and ceruloplasmin levels observed in the arthritic animals were also found to be significantly restored in MER treated rats. Histopathology of paw tissue showed decreased oedema formation and cellular infiltration on supplementation with MER. Thus the results demonstrated the potential beneficiary effect of methanolic extract of Ruta graveolens on adjuvant induced arthritis in rats. Received 11 September 2008; accepted 22 January 2009     

Neuroprotectant effects of iso-osmolar D-mannitol to prevent Pacific ciguatoxin-1 induced alterations in neuronal excitability: a comparison with other osmotic agents and free radical scavengers

The basis for the neuroprotectant effect of D-mannitol in reducing the sensory neurological disturbances seen in ciguatera poisoning, is unclear. Pacific ciguatoxin-1 (P-CTX-1), at a concentration 10 nM, caused a statistically significant swelling of rat sensory dorsal root ganglia (DRG) neurons that was reversed by hyperosmolar 50 mM D-mannitol. However, using electron paramagnetic resonance (EPR) spectroscopy, it was found that P-CTX-1 failed to generate hydroxyl free radicals at concentrations of toxin that caused profound effects on neuronal excitability. Whole-cell patch-clamp recordings from DRG neurons revealed that both hyper- and iso-osmolar 50 mM D-mannitol prevented the membrane depolarisation and repetitive firing of action potentials induced by P-CTX-1. In addition, both hyper- and iso-osmolar 50 mM D-mannitol prevented the hyperpolarising shift in steady-state inactivation and the rise in leakage current through tetrodotoxin (TTX)-sensitive Na(v) channels, as well as the increased rate of recovery from inactivation of TTX-resistant Na(v) channels induced by P-CTX-1. D-Mannitol also reduced, but did not prevent, the inhibition of peak TTX-sensitive and TTX-resistant I(Na) amplitude by P-CTX-1. Additional experiments using hyper- and iso-osmolar D-sorbitol, hyperosmolar sucrose and the free radical scavenging agents Trolox and L-ascorbic acid showed that these agents, unlike D-mannitol, failed to prevent the effects of P-CTX-1 on spike electrogenesis and Na(v) channel gating. These selective actions of D-mannitol indicate that it does not act purely as an osmotic agent to reduce swelling of nerves, but involves a more complex action dependent on the Na(v) channel subtype, possibly to alter or reduce toxin association.     

Recombinant arginine deiminase as a differential modulator of inducible (iNOS) and endothelial (eNOS) nitric oxide synthetase activity in cultured endothelial cells

Modulation of the extracellular level of arginine, substrate for nitric oxide synthetases, is a promising modality to alleviate certain pathological conditions where excess nitric oxide (NO) is produced. However, complications arise, as only preferential inhibition of the inducible nitric oxide synthetase (iNOS), but not endothelial nitric oxide synthetase (eNOS), is desired for the treatment of NO over-production. We investigated the effect of arginine deprivation mediated by a recombinant arginine deiminase (rADI) on the activity of iNOS and eNOS in an endothelial cell line, TR-BBB. Our results demonstrated that cytokine-induced NO production depends on the extracellular arginine as substrate. However, if sufficient citrulline is present in the medium, A23187-activated NO production by eNOS does not rely on extracellular arginine. Treatment with rADI can markedly inhibit cytokine-induced NO production via iNOS, but not A23187-activated NO production via eNOS. Our results also showed that the decrease of NO production by iNOS could be achieved by depleting arginine from the medium even under the conditions that would up-regulate iNOS expression. Thus, rADI appears to be a novel selective modulator of iNOS activity that may be a used as a tool in the study of pathological disorders where NO over-production plays a key role.     

Neolignans from North American Magnolia Species with Cyclooxygenase 2 Inhibitory Activity

Objectives:  Based upon reported ethnomedicinal use by Native Americans, extracts and pure isolates from leaves and seeds of Magnolia grandiflora, M. virginiana, M. acuminata and M. macrophylla, all native to the Southeastern United States, were investigated for their anti-inflammatory potential against cyclooxygenase 2 (COX-2). Material and methods:  The extracts and pure compounds from Magnolia species were tested for their production of prostaglandin E₂ (PGE₂) using a mouse macrophage (RAW 264.7) assay where cells were stimulated by lipopolysaccharide. Results:  Leaf extracts were moderately active (44–58% inhibition at 50 μg/ml) whereas seed extracts showed significant activity of 54–88% inhibition, respectively. In the seed extract of M. grandiflora, honokiol, magnolol and 4’-O-methylhonokiol strongly inhibited COX-2 (IC₅₀: 1.2–2.0 μg/ml), 3-O-methylmagnolol was moderately active while a new compound was inactive towards COX-2. The neolignans were not cytotoxic to macrophages (RAW 264.7) and kidney fibroblast (VERO) cells in vitro. Conclusions:  The results indicate that the reported ethnomedicinal use of the investigated Magnolia species is in agreement with anti-inflammatory activity of their respective compounds. Received 8 December 2007; accepted 16 January 2009     

The clinical assessment of transitional vertebrae and back pain

This study examines the relationship between radiological evidence of lumbar transitional vertebrae (LTV) and the clinical presentation of low back pain (LBP). A retrospective review of 232 consecutive patients presenting at a specialist musculo-skeletal clinic with LBP was conducted. The medical chart for each patient was reviewed for: gender, birth date, symptoms, physical findings, imaging results, and medications prescribed. Subjects were recognized as having a lumbar transitional vertebra if it was noted on their x-ray report. The prevalence of LTV was 9.5 %. This study is consistent with previous research, indicating that the prevalence of LTV is not significantly higher amongst patients with LBP. However, this study also provides furthur detail about the clinical presentation and management of patients with LTV. The information presented in this study will assist health care professionals in determining the clinical significance of a LTV seen on an x-ray film or noted in a radiologist’s report. Received 16 March 2008; accepted 1 August 2008     

A novel approach to the discovery of non-systemic anti-inflammatory steroids; Antedrug

Therapeutic use of anti-inflammatory steroids is limited due primarily to their systemic suppressive effects on pituitary function and the immune system. To overcome the clinical limitation, a new approach toward the discovery of non-systemic anti-inflammatory steroids is based upon the antedrug concept introduced by this laboratory. The new concept describes locally active agents which are designed to undergo a predictable biotransformation to inactive metabolites upon entry into systemic circulation from the applied site. Thus, true antedrugs are devoid of systemic adverse effects. In a continuing effort, 16alpha-carboxylate and isoxazoline derivatives of prednisolone have been synthesized and screened. In the croton oil-induced ear edema bioassay, the following relative potencies were obtained setting hydrocortisone=1.0; 3a, 1.5; 3b, 3.1; 4a, 4.0; 4b, 12.2; 5b, 8.2; 6b, 11.2; 7a, 1.9; 7b, 4.1; 8a, 3.3; 8b, 6.8; 9a, 0.7; 9b, 8.6; 10a, 2.6; 10b, 7.4. Results of the five-day bioassay indicated that, in contrast to the parent compound, the novel steroidal antedrugs did not significantly alter body weight gain, thymus weights, adrenal weights or plasma corticosterone levels. Taken together, the antedrug concept appears to be a fundamentally sound strategy for the separation of local anti-inflammatory activity from systemic adverse effects.     

Anti-inflammatory activities of ethanolic extract of <Emphasis Type="Italic">Carica papaya</Emphasis> leaves

The anti-inflammatory activity of an ethanolic extract of Carica papaya leaves was investigated in rats using carrageenan induced paw oedema, cotton pellet granuloma and formaldehyde induced arthritis models. Experimental animals received 25-200 mg/Kg (orally) of the extracts or saline (control group) and the reference group received 5 mg/ Kg of indomethacin. The ulcerogenic activity of the extract was also investigated. The results show that the extracts significantly (p <0.05) reduced paw oedema in the carrageenan test. Likewise the extract produced significant reduction in the amount of granuloma formed from 0.58 +/-0.07 to 0.22 +/-0.03 g. In the formaldehyde arthritis model, the extracts significantly reduced the persistent oedema from the 4th day to the 10th day of the investigation. The extracts also produced slight mucosal irritation at high doses. The study establishes the anti-inflammatory activity of Carica papaya leaves.     

Soy isoflavones and their bone protective effects

Several observational studies have suggested that populations with a high dietary soy intake have a lower incidence of osteoporosis-related fractures when compared to Western populations. However, there has not been consistent data to show that soy isoflavones protect against or lessen bone loss. Studies in our laboratory showed that genistein, the major soy isoflavone, could stimulate osteoblastic functions as well as human breast cancer cell growth. These studies raised the concern of whether it would be safe for women who have a prior history of breast cancer to consume soy isoflavone for management of postmenopausal osteoporosis. As increasing the purity of genistein is known to increase its ability to induce human breast cancer cell growth, current effort in our laboratory is to determine if the in vivo bone protective effects will be affected by the complexity of the soy isoflavones extract in ovariectomized mice.     

A celebration of wine: wine IS medicine

Wine describes a diverse commodity class composed of the yeast fermentation products of the must, or juice, pressed from grapes, the fruit of genus Vitis, but both in animal and human studies, wine demonstrates beneficial properties that are independent from the presence of alcohol. These benefits for health are mostly associated with polyphenols, and are absorbable from wine but poorly from unfermented grape juice. Dealcoholised wine is providing all the benefits without the toxicity, and is very affordable; improvements in the organoleptic quality of dealcoholised wine(s) as well as massive distribution are current challenges.     

Measurement of Protein Diffusion Through Poly(d,l-Lactide-Co-Glycolide)

A novel method was developed for studying the diffusion of proteins through poly(d,l-lactide-co-glycolide) (PLG), using a diffusion cell. To develop improved formulations for the controlled release of encapsulated drugs it is important to understand the underlying release mechanisms. When using low-molecular-weight PLG as the release-controlling polymer, diffusion through the pores is often proposed as the main release mechanism. The experimental set-up and method of determining the diffusion coefficient were thoroughly evaluated with regard to the reliability and the influence of the stirring rate. A procedure for spraying thin films of PLG onto a filter, which could be placed in the diffusion cell, was optimized. The method was then applied to the determination of the diffusion coefficient of human growth hormone (hGH) through a PLG film. The results show that the method enables measurements of the diffusion coefficient through the polymer film. Neither the stirring rate nor the concentration of hGH influenced the diffusion coefficient. The diffusion coefficient of hGH through degraded PLG films was 5.0 · 10^{? 13} m²/s, which is in the range that could be expected, i.e., several orders of magnitude smaller than its the diffusivity in pure water. The reproducibility was good, considering the dynamic properties of PLG, i.e., the difference in diffusion coefficients, at, for example, different stages of degradation and for different compositions of PLG, is expected to be much higher. The variation is probably also present in PLG films used for controlled-release formulations. Although the PLG film contains a large amount of water, a considerable time elapsed before pores of sufficient size formed and diffusion through the film started. In two-component diffusion experiments, the difference in diffusion rate did not correspond to the difference in molecular weight of the solutes, indicating a size exclusion effect. This method can be used to study the effect of changes in the formulation specification. By studying the change in the diffusion coefficient through the degradation process of PLG, or similar polymers, a better understanding of diffusion and, thus, also release mechanisms can be obtained.