Effects of a mixture of fatty acids from sugar cane (Saccharum officinarum L.) wax oil in two models of inflammation: zymosan-induced arthritis and mice tail test of psoriasis.

A mixture of fatty acids obtained from sugar cane (Saccharum officinarum L.) wax oil (FAM), in which the main constituents are palmitic, oleic, linoleic, and linolenic acids, was evaluated in two models of inflammation: zymosan-induced arthritis and in the tail test for psoriasis, both on mice. In the first model, FAM significantly reduced zymozan-induced increase of beta glucuronidase (DE(50) 90+/-7 mg/kg). Histopathological studies showed inhibition in cellular infiltration and reduction of synovial hyperplasia and synovitis, whereas in the second test, histopathological and ultrastructural studies showed that topical application of FAM induced orthokeratosis with the presence of keratohyalin granules in the previously parakeratotic adult mouse tail, and without effects on epidermal thickness. The ED(50) of FAM in this model was 155+/-10 mg. The results of our studies showed that topical application of FAM exerts an important anti-inflammatory activity in both tests without evidence of irritant effects. The anti-inflamatory effects exerted by FAM may be due to its inhibitory effects on arachidonic acid metabolism. To our knowledge, this is the first report on the anti-inflammatory effect of sugar cane by-products in experimental models of arthritis and psoriasis.

C-phycocyanin: a biliprotein with antioxidant, anti-inflammatory and neuroprotective effects.

Phycocyanin (Pc) is a phycobiliprotein that has been recently reported to exhibit a variety of pharmacological properties. In this regard, antioxidant, anti-inflammatory, neuroprotective and hepatoprotective effects have been experimentally attributed to Pc. When it was evaluated as an antioxidant in vitro, it was able to scavenge alkoxyl, hydroxyl and peroxyl radicals and to react with peroxinitrite (ONOO(-);) and hypochlorous acid (HOCl). Pc also inhibits microsomal lipid peroxidation induced by Fe(+2)-ascorbic acid or the free radical initiator 2,2' azobis (2-amidinopropane) hydrochloride (AAPH). Furthermore, it reduces carbon tetrachloride (CCl(4))-induced lipid peroxidation in vivo. Pc has been evaluated in twelve experimental models of inflammation and exerted anti-inflammatory effects in a dose-dependent fashion in all of these. Thus, Pc reduced edema, histamine (Hi) release, myeloperoxidase (MPO) activity and the levels of prostaglandin (PGE(2)) and leukotriene (LTB(4)) in the inflamed tissues. These anti-inflammatory effects of Pc can be due to its scavenging properties toward oxygen reactive species (ROS) and its inhibitory effects on cyclooxygenase 2 (COX-2) activity and on Hi release from mast cells. Pc also reduced the levels of tumor necrosis factor (TNF-alpha) in the blood serum of mice treated with endotoxin and it showed neuroprotective effects in rat cerebellar granule cell cultures and in kainate-induced brain injury in rats.

Influence of C-phycocyanin on hepatocellular parameters related to liver oxidative stress and Kupffer cell functioning.

OBJECTIVES: Kupffer cells, liver macrophages involved in immunomodulation, phagocytosis, and biochemical attack, can induce cytotoxicity and inflammation when their activity is exacerbated. The aim of this study was to evaluate the effects of C-phycocyanin on Kupffer cell functioning considering its antioxidant and anti-inflammatory properties. MATERIALS AND METHODS: Actions of C-phycocyanin on colloidal carbon phagocytosis, carbon-induced respiratory burst activity, and sinusoidal lactate dehydrogenase (LDH) release were studied in isolated perfused mouse liver. The influence of C-phycocyanin on tumor necrosis factor-a (TNF-alpha) and nitrite levels in serum and liver nitric oxide synthase (NOS) activity was assessed in rats subjected to thyroid hormone (T3) administration, a condition known to underlie hepatic oxidative stress comprising an increased Kupffer cell activity. RESULTS: C-phycocyanin elicited a concentration-dependent inhibition of carbon phagocytosis and carbon-induced O2 uptake (IC50 = 0.2 mg/ml) by perfused livers, with a 52% diminution in the carbon-induced sinusoidal release of LDH being found at a concentration of 0.25 mg/ml. Thyroid calorigenesis induced an 82-fold increase in serum TNF-alpha levels, an effect that was suppressed by pretreatment with C-phycocyanin, the antioxidant alpha-tocopherol, and by the Kupffer cell inactivator gadolinium chloride. C-phycocyanin also suppressed the T3-induced increases in serum nitrite levels (234%) and in the activity of hepatic NOS (75%). CONCLUSIONS: C-phycocyanin significantly decreases Kupffer cell phagocytosis and the associated respiratory burst activity, effects that may contribute to the abolition of oxidative stress-induced TNF-alpha response and NO production by hyperthyroid state.

Role of histamine in the inhibitory effects of phycocyanin in experimental models of allergic inflammatory response.

It has recently been reported that phycocyanin, a biliprotein found in the blue-green microalgae Spirulina, exerts anti-inflammatory effects in some animal models of inflammation. Taking into account these findings, we decided to elucidate whether phycocyanin might exert also inhibitory effects in the induced allergic inflammatory response and on histamine release from isolated rat mast cells. In in vivo experiments, phycocyanin (100, 200 and 300mg/kg post-orally (p.o.)) was administered 1 h before the challenge with 1 microg of ovalbumin (OA) in the ear of mice previously sensitized with OA. One hour later, myeloperoxidase activity and ear edema were assessed. Phycocyanin significantly reduced both parameters. In separate experiments, phycocyanin (100 and 200 mg/kg p.o.) also reduced the blue spot area induced by intradermal injections of histamine, and the histamine releaser compound 48/80 in rat skin. In concordance with the former results, phycocyanin also significantly reduced histamine release induced by compound 48/80 from isolated peritoneal rat mast cells. The inhibitory effects of phycocyanin were dose dependent. Taken together, our results suggest that inhibition of allergic inflammatory response by phycocyanin is mediated, at least in part, by inhibition of histamine release from mast cells.

Effects of phycocyanin extract on tumor necrosis factor-alpha and nitrite levels in serum of mice treated with endotoxin.

Phycocyanin is a biliprotein which exerts antioxidative and anti-inflammatory effects in various in vivo and in vitro experimental models. In this study phycocyanin effects on tumor necrosis factor-alpha (TNF alpha) and nitrite levels in serum of mice treated with lipopolysaccharide (LPS) was examined. TNF alpha was measured by cytotoxicity on L-929 cells and nitrite by the Griess reaction, after reduction of all nitrates to nitrites by nitrate reductase, 1 h after LPS injection (0.5 mg/kg i.p.) there was a significant increase in TNF alpha levels in mouse serum. Phycocyanin (50-300 mg/kg p.o.), administered 1 h before LPS, reduced dose-dependently the TNF alpha concentration in serum. After 18 h, LPS (30 mg/kg i.p.) also induced a substantial increase in serum nitrite levels, which were reduced dose-dependently by phycocyanin pretreatment (100-300 mg/kg p.o.). The results indicate that phycocyanin exerts inhibitory effects on TNF alpha and NO production which might be ascribed to the antioxidative properties of the biliprotein.

Anti-inflammatory activity of phycocyanin extract in acetic acid-induced colitis in rats.

The anti-inflammatory effect of c-phycocyanin extract was studied in acetic acid-induced colitis in rats. Phycocyanin (150, 200 and 300 mg kg(-1) p.o.) was administered 30 min gbefore induction of colitis with enema of 1 ml of 4% acetic acid per rat. Twenty-four hours later myeloperoxidase (MPO) activity was determined as well as histopathological and ultrastructural studies were carried out in colonic tissue. Phycocyanin substantially reduced MPO activity which was increase din the control colitis group. Also, histopathological and ultrastructural studies were carried out in colonic tissue. Phycocyanin substantially reduced MPO activity which was increased in the control colitis group. Also, histopathological and ultrastructural studies showed inhibition in inflammatory cell infiltration and reduction to some extent in colonic damage in rats treated with phycocyanin. The probable role of antioxidative and the scavenging properties of phycocyanin against reactive oxygen species in the anti-colitic effect is discussed in this paper. To our knowledge this is the first report on the anti-inflammatory effect of phycocyanin in an experimental model of colitis.

ANTI-INFLAMMATORY ACTIVITY OF PHYCOCYANIN EXTRACT IN ACETIC ACID-INDUCED COLITIS IN RATS.

The anti-inflammatory effect of c-phycocyanin extract was studied in acetic acid-induced colitis in rats. Phycocyanin (150, 200 and 300 mg kg-1 p.o.) was administered 30 min before induction of colitis with enema of 1 ml of 4% acetic acid per rat. Twenty-four hours later myeloperoxidase (MPO) activity was determined as well as histopathological and ultrastructural studies were carried out in colonic tissue. Phycocyanin substantially reduced MPO activity which was increased in the control colitis group. Also, histopathological and ultrastructural studies showed inhibition in inflammatory cell infiltration and reduction to some extent in colonic damage in rats treated with phycocyanin. The probable role of antioxidative and the scavenging properties of phycocyanin against reactive oxygen species in the anti-colitic effect is discussed in this paper. To our knowledge this is the first report on the anti-inflammatory effect of phycocyanin in an experimental model of colitis.(c) 1999 The Italian Pharmacological Society.

Antioxidant and anti-inflammatory properties of C-phycocyanin from blue-green algae.

OBJECTIVE: Phycocyanin is a pigment found in blue-green algae which contains open chain tetrapyrroles with possible scavenging properties. We have studied its antioxidant properties. MATERIALS AND METHODS: Phycocyanin was evaluated as a putative antioxidant in vitro by using: a) luminol-enhanced chemiluminescence (LCL) generated by three different radical species (O2-, OH., RO.) and by zymosan activated human polymorphonuclear leukocytes (PMNLs), b) deoxyribose assay and c) inhibition of liver microsomal lipid peroxidation induced by Fe+2-ascorbic acid. The antioxidant activity was also assayed in vivo in glucose oxidase (GO)-induced inflammation in mouse paw. RESULTS: The results indicated that phycocyanin is able to scavenge OH. (IC50 = 0.91 mg/mL) and RO. (IC50 = 76 microg/mL) radicals, with activity equivalent to 0.125 mg/mL of dimethyl sulphoxide (DMSO) and 0.038 microg/mL of trolox, specific scavengers of those radicals respectively. In the deoxyribose assay the second-order rate constant was 3.56 x 10(11) M(-1) S(-1), similar to that obtained for some non-steroidal anti-inflammatory drugs. Phycocyanin also inhibits liver microsomal lipid peroxidation (IC50 = 12 mg/mL), the CL response of PMNLs (p < 0.05) as well as the edema index in GO-induced inflammation in mouse paw (p < 0.05). CONCLUSIONS: To our knowledge this is the first report of the antioxidant and anti-inflammatory properties of c-phycocyanin.

Current views on the pharmacological properties of the immunomodulator, lobenzarit disodium.

Lobenzarit disodium (LBZ) is an immunomodulator and antioxidative drug developed and used successfully in Japan for the treatment of rheumatoid arthritis (RA). Studies in animals and humans have shown striking differences between the pharmacological profile of LBZ and nonsteroidal antiinflammatory drugs commonly used in the treatment of RA. LBZ does not inhibit the biosynthesis of prostaglandins and leukotrienes and is ineffective on acute inflammatory reactions induced in animals. Therefore, its usefulness in RA is ascribed to immunopharmacological properties of the drug. Currently, evidence is available that B- and T-lymphocytes are targets of LBZ's actions which regulates the functions of these cells. LBZ reduces IgE titers in serum of sensitized mice by activating suppressor T-lymphocytes and inhibiting anaphylactic shock induced by ovalbumin. These results provide evidence in favor of the potential use of LBZ in the treatment of allergic diseases, which must be elucidated in controlled double-blind clinical trials. The suppressive effects of LBZ on the function of activated B cells as well as in the production of anti-DNA antibody have been reported. These findings suggest that LBZ may be effective in the treatment of other autoimmune diseases such as lupus erythematosus that are also characterized by the production of autoantibodies from activated B cells. Recently, an open clinical trial in patients with systemic lupus erythematosus supports this point of view. Other potential therapeutic uses of LBZ are in autoimmune-related diabetes and in autoimmune liver disease which are documented in this review. LBZ also selectively antagonizes the contractile responses of isolated rabbit aorta strips induced by thromboxane A2-mimetic U-46619. This result provides evidence in favor of an antagonist of LBZ at the level of TxA2 receptors and supports the potential usefulness of LBZ in some cardiovascular disorders such as cardiopulmonary diseases and thrombosis. LBZ is a scavenger of oxygen-free radicals such as hydroxyl radicals, superoxide, peroxyl and singlet oxygen. This property contributes substantially to its pharmacological and therapeutic profile as well as its mechanism of action.

Effects of Cuban red propolis on galactosamine-induced hepatitis in rats.

Using transmission electron microscopy and biochemical analysis, the effect of cuban red propolis against hepatitis induced by 1,000 mg kg-1 of galactosamine in rats was studied. An ethanolic extract of propolis was prepared and it was given to rats at doses of 10, 50 and 100 mg kg-1, 30 min before the hepatotoxin. Propolis extract prevented hepatocytes alterations induced by galactosamine. It was mainly seen in rough endoplasmic reticulum, Golgi complex, nucleus and plasma membrane of hepatocytes. Propolis extract induced reversion of the increased activity of alanine aminotransferase and malondialdehyde concentration in the serum of rats treated with galactosamine. The probable role of antioxidant activity of propolis in the prevention of hepatitis is discussed in this paper.

Protective effects of lobenzarit against allyl alcohol-induced hepatotoxicity in mice and rats.

The protective effects of lobenzarit disodium against the toxicity of allyl alcohol were investigated in vitro using isolated rat hepatocytes and in vivo using mice. In mice, at i.p doses of 25, 50 and 100 mg/kg lobenzarit significantly decreased the activity of alanine amino transferase (ALT) in serum and the concentration of malondialdehyde (MDA) in liver homogenates, both of which were increased by allyl alcohol at a dose of 64 mg/kg. At concentrations of 0.2 and 0.3 mM, lobenzarit reduced the release of lactate dehydrogenase (LDH) and the levels of malondialdehyde (MDA) induced by 0.4 mM of allyl alcohol in isolated rat hepatocytes. However, lobenzarit did not increase the levels of reduced glutathione (GSH) depleted by allyl alcohol in any of the two experimental models. The protective effects of lobenzarit were dose- and concentration-dependent and they were most obvious when lobenzarit was administered 30 min before allyl alcohol. It is concluded that lobenzarit exerts the observed protective effects most likely by its antioxidant properties.

Protective effects of Propolis extract on allyl alcohol-induced liver injury in mice.

Potential protective effects of ethanolic extract of Cuban red propolis against toxicity induced by allyl alcohol in mice was investigated. Propolis at doses of 25, 50 and 100 mg/i.p. significantly decreased the activity of alanine amino transferase (EC 2.6.1.2) in serum and the levels of mal-ondialdehyde in mouse liver after induction with a dose of 64 mg/kg of allyl alcohol. However, propolis did not increase the concentration of reduced glutathione in mouse liver which is depleted by allyl alcohol. Propolis also reduced liver damage induced by allyl alcohol in mice. This effect was observed by electron microscopy. The hepatoprotective effects of propolis were dose-dependent and they were produced when propolis was administered 30 min before allyl alcohol administration. It is indicated that the ethanolic extract of red propolis exerts potential hepatoprotective effects in this experimental model which is probably caused by antioxidative properties (e.g. scavenging action against oxygen radicals) of this extract.

Histopathological evaluation on the effect of red propolis on liver damage induced by CCl4 in rats.

A histopathological evaluation was performed on liver of rats treated with carbon tetrachloride (CCl4) and 25,50 and 100 mg/kg of Cuban red propolis (RP) extract. Additionally, alanine aminotransferase (ALT) in serum and liver triglycerides were determined in all animals. The morphometric study included the count of ballooned cells at the zone III of the Rappaport acini and the assessment of a software program to estimate the extension of steatosis area. A significant reduction of ballooned cells count in liver was observed at three dose levels of RP extract with respect to rats treated only with CCl4. Also, a certain reduction of steatosis degree as well as decreased concentration of liver triglycerides and ALT activity were found in three groups of rats treated with RP extract and CCl4 in relation to those treated with the hepatotoxin. Taken together, the histopathological and biochemical findings show hepatoprotective effects of RP extract in CCl4-induced liver damage in rats, probably due to the antioxidant effect of RP.

Mechanism of protection of lobenzarit against paracetamol-induced toxicity in rat hepatocytes.

The protective effects of lobenzarit, an antioxidative agent and antirheumatic drug, on the cytotoxicity of paracetamol in rat hepatocytes were studied, as well as the inhibitory effects of lobenzarit on cytochrome P-450s and glutathione S-transferases (GSTs) in rat liver. Paracetamol was selected as a model toxin, since it is known to be bioactivated by specific cytochrome P-450s presumably to N-acetyl-p-benzoquinoneimine, a reactive metabolite which upon overdosage of paracetamol causes protein and non-protein thiol depletion, lipid peroxidation and cytotoxicity measurable as LDH leakage. At concentrations of lobenzarit of 0.2 and 0.3 mM, added 30 min before paracetamol, the drug prevented paracetamol-induced leakage of lactate dehydrogenase (LDH) almost completely and lipid peroxidation (LPO) and depletion of glutathione (GSH) substantially and also the formation of the 3-glutathionyl conjugate of paracetamol. However, at a concentration of 0.05 mM Lobenzarit did not protect anymore against the paracetamol toxicity, When added to the hepatocytes 1 h and 2 h before paracetamol, 0.05 and 0.2 and 0.3 mM concentrations of lobenzarit did not protect against the cytotoxicity induced by paracetamol either. Lobenzarit did not inhibit cytochromes P-450 1A1/1A2, 2B1/2B2 and 2E1 which were measured as ethoxyresorufin O-deethylation (EROD) activity in beta-naphthoflavone-induced rat liver microsomes, as pentoxyresorufin de-pentylation (PROD) activity in phenobarbital-induced microsomes and as p-nitrophenol hydroxylation (PNPH) activity in pyrazol-induced microsomes. Lobenzarit did not show inhibition of glutathione S-transferase (GST) activity towards 1-chloro-2,4-dinitrobenzene (CDNB) in cytosol from liver of rats treated with phenobarbital, pyrazol and beta-naphthoflavone either. It is concluded that the cytoprotective effect of lobenzarit is most likely due to its antioxidant effects and/or to its ability to stimulate GSH reductase.

Hepatoprotective effects of lobenzarit disodium on acetaminophen-induced liver damage in mice.

We have studied the effects of the immunomodulator drug lobenzarit in the model of acute hepatotoxicity induced by a high oral dose (600 mg/kg) of acetaminophen in mice. Lobenzarit at doses of 25, 50 and 100 mg/kg i.p. decreased significantly the activity of alanine aminotransferase in serum, which was increased by acetaminophen alone, and increased the concentration of reduced glutathione in mice liver, which is depleted by acetaminophen. Lobenzarit also reduced liver damage induced by acetaminophen in mice, which was observed by electron microscopy. The hepatoprotective effects of lobenzarit were dose-dependent and they were produced when lobenzarit was administered 30 min before acetaminophen or 2 and 4 h after it. It is concluded that lobenzarit exerts some effects which resemble those of an antidote of acetaminophen such as N-acetylcysteine.