On the activity of trifluoperazine and palmitoylcarnitine in mice: delayed hypersensitivity models

Trifluoperazine reduces cuprizone-induced demyelination via targeting Nrf2 and IKB in mice

Multiple sclerosis (MS) is one of the most common neurodegenerative diseases. In this disease, the immune system attacks oligodendrocyte cells and the myelin sheath of myelinated neurons in the central nervous system, causing their destruction. These conditions lead to impaired conduction of nerve impulses and are manifested by symptoms such as weakness, fatigue, visual and motor disorders. This study aimed to evaluate the ability of trifluoperazine (TF) to improve cuprizone-induced behavioral and histopathological changes in the prefrontal cortex of C57BL/6 male mice. Demyelination was induced by adding 0.2% cuprizone (CPZ) to the standard animal diet for 6 weeks. Three doses of TF (0.5, 1 and 2 mg/kg/day; i.p.) were given once daily for the last 2 weeks of treatment. Treatment with CPZ induced a weight loss during 6 weeks of treatment compared to the control group, which was reversed by the administration of TF. Behavioral tests (pole test and rotarod performance test) showed a decrease in motor coordination and balance in the group treated with CPZ (P < 0.01). Treatment with TF during the last two weeks was able to improve these motor deficiencies. Histopathological examination also evidenced an increase in demyelination in the CPZ group, which was improved by TF administration. In addition, CPZ intake significantly decreased the cerebral cortex levels of p-Nrf2 (P < 0.001) and increased the levels of p-IKB (P < 0.001) and, these changes were normalized in the TF groups. TF administration also reversed the increased levels of nitrite and the reduced activity of the antioxidant enzyme superoxide dismutase associated with CPZ exposure. TF can to reduce the harmful effects of CPZ by reducing the demyelination and modulating the Nrf2 and NF-kB signaling pathways.

The Protective Roles of PPARα Activation in Triptolide-induced Liver Injury

Triptolide (TP), one of the main active ingredients in Tripterygium wilfordii Hook F, is clinically used to treat immune diseases but is known to cause liver injury. The aim of this study was to investigate the biomarkers for TP-induced hepatotoxicity in mice and to determine potential mechanisms of its liver injury. LC/MS-based metabolomics was used to determine the metabolites that were changed in TP-induced liver injury. The accumulation of long-chain acylcarnitines in serum indicated that TP exposure disrupted endogenous peroxisome proliferator-activated receptor α (PPARα) signaling. TP-induced liver injury could be alleviated by treatment of mice with the PPARα agonist fenofibrate, while the PPARα antagonist GW6471 increased hepatotoxicity. Furthermore, fenofibrate did not protect Ppara-/- mice from TP-induced liver injury, suggesting an essential role for the PPARα in the protective effect of fenofibrate. Elevated long-chain acylcarnitines may protect TP-induced liver injury through activation of the NOTCH-NRF2 pathway as revealed in primary mouse hepatocytes and in vivo. In agreement with these observations in mice, the increase of long-chain acylcarnitines was observed in the serum of patients with cholestatic liver injury compared to heathy volunteers. These data demonstrated the role of PPARα and long-chain acylcarnitines in TP-induced hepatotoxicity, and suggest that modulation of PPARα may protect against drug-induced liver injury.

Toxicology and immunology of Ganoderma lucidum polysaccharides in Kunming mice and Wistar rats

In the present work, the toxicology and immunology of polysaccharides from fruiting body of Ganoderma lucidum (GPs) were investigated. No abnormal clinical-symptoms or deaths and no significant difference in body weight and food in-taking rate were found in Wistar rats during the 30-day feeding administration. No significant differences were found in each hematology value, clinical chemistry value and organ/body weight ratio, either. It had no mutagenicity due to the negative experimental results of Ames test, micronucleus test of polychromatic erythrocyte, sperm abnormality test, and chromosome aberration test in Kunming mice, respectively. The immune experiments indicated that high-dose GPs had immune effects in increasing the degree of toe swelling and enhancing the primary immune response to SRBC (P<0.01). But no-significant influence of GPs on the phagocytic function of mononuclear macrophages (MΦ) could be obtained.

Orally Administered Dendrobium Officinale and its Polysaccharides Enhance Immune Functions in BALB/c Mice

The immunoactivity was evaluated of Dendrobium officinale Kimura & Migo, a Chinese herbal plant, and its crude polysaccharides. Different dosages of D. officinale and its polysaccharides were orally administered to healthy BALB/c mice. The control group was given distilled water. After 4 weeks, immune parameters, including cellular immunity (delayed-type hypersensitivity and natural killer cell activity), humoral immunity (serum hemolytic complement activity), nonspecific immunity (peritoneal macrophage phagocytosis) and interferon-γ production by splenocytes were measured. The results showed that D. officinale and its polysaccharides can significantly enhance cellular immunity and nonspecific immunity in mice. Humoral immunity was also enhanced after oral administration of D. officinale, but the polysaccharides had no influence. Both D. officinale and its polysaccharides markedly increased IFN-γ production by murine splenocytes. Six fractions were isolated from the polysaccharides; the molecular weight of the major fraction was 533,700 Da, and composed of mannose, glucose and rhamnose in a molar ratio of 7.3:1.3:1.0.

Possible role of macrophages induced by an irridoid glycoside (RLJ-NE-299A) in host defense mechanism

In order to explore the possible role of macrophages and other necessary immune competent (T and B) cells in the modulation of immune responses, an attempt was made to study the immunomodulatory effect of an irridoid glycoside (RLJ-NE-299A) isolated from the roots of Picrorhiza kurroa. Both in vitro and in vivo studies were used to evaluate the effect of RLJ-NE-299A on humoral, cellular, and phagocytic activity of macrophages. The data obtained in the present study showed that RLJ-NE-299A significantly increased sheep red blood cell (SRBC) and induced antibody (IgM and IgG) titer and delayed type hypersensitivity (DTH) reaction in mice. Besides augmenting the humoral and cell-mediated immune response, it induced macrophage phagocytosis and stimulated cytokine-induced macrophage activation and nitric oxide (NO) production, which resulted in a high degree of protection against Candida albicans and Salmonella typhimurium infections. Flow cytometric analysis indicated the enhanced expression of co-stimulatory surface molecules CD80 and CD86. The ability of RLJ-NE-299A to upregulate these cell surface antigens involved in antigen presentation may provide an explanation for the increased T-cell mediated immunity involving macrophages. Taken together this in vitro and in vivo preclinical data suggests that RLJ-NE-299A acts as an effective immunomodulator specifically to improve macrophage function during infections. The effects of this agent on these cells at concentrations relevant to in vivo therapy support its immunopharmacologic application to modify cellular immunity.

A new chloroquinolinyl chalcone derivative as inhibitor of inflammatory and immune response in mice and rats

The synthetic chalcone derivative 1-(2,4-dichlorophenyl)-3-(3-(6,7-dimethoxy-2-chloroquinolinyl))-2-propen-1-one (CIDQ) was evaluated for its anti-inflammatory, analgesic and immunomodulatory efficacy in-vitro and in-vivo. CIDQ concentration-dependently inhibited the production of nitric oxide (NO) (IC50 4.3 μM) and prostaglandin E2 (PGE2) (IC50 1.8 μM) in RAW 264.7 macrophages stimulated with lipopolysaccharide. Human mononuclear cell proliferation was significantly inhibited by 10 μM CIDQ. Oral administration of CIDQ (10–30 mg kg−1) in the 24-h zymosan-stimulated mouse air-pouch model produced a dose-dependent reduction of cell migration as well as NO and PGE2 levels in exudates. CIDQ (20 mg kg−1, p.o.) inhibited ear swelling and leucocyte infiltration in the delayed-type hypersensitivity response to 2,4-dinitrofluorobenzene in mice. In the rat adjuvant-arthritis model, this compound reduced joint inflammation as well as PGE2 and cytokine levels. In addition, CIDQ displayed analgesic effects in the phenylbenzoquinone-induced abdominal constriction model in mice and in the late phase of the nociceptive response to formalin. Our findings indicated the potential interest of CIDQ in the modulation of some immune and inflammatory conditions.

Immunomodulatory activity of Zingiber officinale Roscoe, Salvia officinalis L. and Syzygium aromaticum L. essential oils: evidence for humor- and cell-mediated responses

OBJECTIVES

The immunomodulatory effect of ginger, Zingiber officinale (Zingiberaceae), sage, Salvia officinalis (Lamiaceae) and clove, Syzygium aromaticum (Myrtaceae), essential oils were evaluated by studying humor- and cell-mediated immune responses.

METHODS

Essential oils were administered to mice (once a day, orally, for a week) previously immunized with sheep red blood cells (SRBCs).

KEY FINDINGS

Clove essential oil increased the total white blood cell (WBC) count and enhanced the delayed-type hypersensitivity (DTH) response in mice. Moreover, it restored cellular and humoral immune responses in cyclophosphamide-immunosuppressed mice in a dose-dependent manner. Ginger essential oil recovered the humoral immune response in immunosuppressed mice. Contrary to the ginger essential oil response, sage essential oil did not show any immunomodulatory activity.

CONCLUSIONS

Our findings establish that the immunostimulatory activity found in mice treated with clove essential oil is due to improvement in humor- and cell-mediated immune response mechanisms.

In vitro and in vivo effects of Ranunculus peltatus subsp. baudotii methanol extract on models of eicosanoid production and contact dermatitis

Ranunculus (Crowfoot) species are numerous and they are all reputed to be counter-irritants and are used in several topical conditions. In order to study the pharmacological mechanisms of action underlying this popular use, a methanol extract of Ranunculus peltatus was tested in vitro in various assays involving eicosanoid and human elastase release by intact cells as well as in vivo, with models of delayed-type hypersensitivity (DTH) contact dermatitis. The extract proved to be a selective inhibitor of the cyclooxygenase-1 pathway, producing the total inhibition of 12-(S)-HHTrE release at 200 microg/mL, while leaving both 5-lipoxygenase and 12-lipoxygenase activities unaffected at the same dose. The n-hexane, chloroform and ethyl acetate fractions of the crude methanol extract inhibited LTB(4) release by intact rat peritoneal neutrophils, but more polar fractions were inactive and did not increase the 5-LOX activity as seen previously for extracts of other Ranunculus species. In the in vivo models, the methanol extract reduced the dinitrofluorobenzene (DNFB)-induced oedema by 40%, but failed to inhibit the oedema brought on by oxazolone. The results agree with the age-old assertion that Water Crowfoot species can be used as a topical antiinflammatory remedy without the prominent irritant action that accompanies the application of non-aquatic Ranunculus species.

Effects of plant alkylphenols on cytokine production, tyrosine nitration and inflammatory damage in the efferent phase of contact hypersensitivity

BACKGROUND AND PURPOSE

The phenolic compounds isoprenylhydroquinone glucoside (IHG), 3,5-dicaffeoylquinic acid (DCA), and its methyl ester (DCE) have previously been shown to inhibit both contact hypersensitivity (CHS) and peroxynitrite reactivity. The present work seeks to establish a relationship between the anti-inflammatory effect and the release of cytokines and tyrosine nitration in skin.

EXPERIMENTAL APPROACH

Murine CHS was developed by means of sensitization and challenge with dinitrofluorobenzene (DNFB) or oxazolone. Ear swelling was measured 24 and 96 h after challenge. Interleukin (IL)-1beta, IL-4, and tumour necrosis factor (TNF)-alpha were measured by ELISA; and the expression of inducible nitric oxide synthase (iNOS) was detected by Western blotting. Histological samples were analysed for 3-nitrotyrosine.

KEY RESULTS

In the oxazolone model, DCE reduced the 24 h swelling by 54% whereas the effect of DCA was lower (40% inhibition). All the test compounds reduced IL-1beta values 24 h after challenge with DNFB or oxazolone, DCE particularly inhibited IL-4 production (74% and 78%, respectively; P<0.01). Tyrosine nitration was also markedly reduced by DCE. In general, the test compounds limited the presence of polymorphonuclear (PMN) leukocytes in the skin.

CONCLUSIONS AND IMPLICATIONS

These results suggest that the effect of 3,5-dicaffeoylquinic esters on CHS is associated with a decrease in the production of interleukins, but not with the inhibition of iNOS expression. Moreover, esterification of the carboxyl group at C-1 enhanced protection against tyrosine nitration in the skin.

New insight into the inhibition of the inflammatory response to experimental delayed-type hypersensitivity reactions in mice by scropolioside A

Scropolioside A, an iridoid isolated from Scrophularia auriculata ssp. pseudoauriculata, showed anti-inflammatory properties against different experimental models of delayed-type hypersensitivity. This iridoid reduced the oedema induced by oxazolone by 79% (72 h) at 0.5 mg/ear while reducing that induced by sheep red blood cells by 47% (18 h), 45% (24 h) and 36% (48 h) at 10 mg/kg. In vivo it reduced both oedema formation and cell infiltration whereas in vitro it reduced the proliferation of activated T-lymphocytes (IC50 of 67.74 microM). Treatment with scropolioside A (100 microM) 18 and 24 h after phytohemagglutinin stimulation increased the number of cells arrested in the subG(0) phase whereas treatment 3 h after stimulation clearly increased the number of cells that passed to the S phase. Scropolioside A also inhibited the production of prostaglandin E2, leukotriene B4, nitric oxide, interleukin-1beta, interleukin-2, interleukin-4, tumour necrosis factor-alpha and interferon-gamma, but had no effect on the production of interleukin-10. Moreover, it modified the expression of both nitric oxide synthase-2 and cyclooxygenase-2, as well as the activation of nuclear factor-kappaB in RAW 264.7 macrophages.

Pharmacological approach to the pro- and anti-inflammatory effects of Ranunculus sceleratus L

Ranunculus sceleratus is a widespread species with unique toxicological and pharmacological activities. The present study seeks to assess this species' ability, both in vitro and in vivo, to modulate processes involved in inflammations. To this end, different extracts from the aerial parts of the plant were tested in several models of acute inflammation induced by tetradecanoylphorbol acetate (TPA), arachidonic acid (AA), and carrageenan, as well as in two models of delayed hypersensitivity induced by oxazolone and dinitrofluorobencene (DNFB). The extracts were also assayed in models of eicosanoid and elastase release by intact cells. When tested in vivo, all of the extracts showed anti-inflammatory or neutral effects. In vitro, non-polar extracts of this species were able to inhibit eicosanoid production, whereas polar extracts enhanced the synthesis of 5(S)-HETE, LTB(4) and 12(S)-HHTrE. The hypothesis of a "counter-irritant" mechanism of action has thus been proposed and is also discussed herein.

Prevention of macrophage-related inflammatory diseases by allergina

The oriental herbal combination allergina has been shown to inhibit allergic inflammation. In the present study, we demonstrate that the oral administration of allergina markedly inhibits the progression of inflammatory diseases, such as graft-versus-host diseases (in the allogeneic bone marrow transplantation and the parent-into-F1 transplantation models), collagen-induced arthritis and sheep red blood cell-induced delayed type hypersensitivity. The immunosuppressive activity of allergina in vivo appears to be associated, at least in part, with the inhibition of tumor necrosis factor-alpha production. In conclusion, our results suggest that allergina could be useful as a immunosuppressive agent for the treatment of macrophage-related inflammatory disease.

Assessment of the anti-inflammatory activity and free radical scavenger activity of tiliroside

Three flavonoids, gnaphaliin, pinocembrin and tiliroside, isolated from Helichrysum italicum, were studied in vitro for their antioxidant and/or scavenger properties and in vivo in different models of inflammation. In vitro tests included lipid peroxidation in rat liver microsomes, superoxide radical generation in the xanthine/xanthine oxidase system and the reduction of the stable radical 1,1-diphenyl-2-pycryl-hydrazyl (DPPH). Acute inflammation was induced by application of 12-O-tetradecanoylphorbol 13-acetate (TPA) to the mouse ear or by subcutaneous injection of phospholipase A(2) or serotonin in the mouse paw. Eczema provoked on the mouse ear by repeated administration of TPA was selected as a model of chronic inflammation. The flavonoids were assayed against sheep red blood cell-induced mouse paw oedema as a model of delayed-type hypersensitivity reaction. The most active compound, both in vitro and in vivo, was tiliroside. It significantly inhibited enzymatic and non-enzymatic lipid peroxidation (IC(50)=12.6 and 28 microM, respectively). It had scavenger properties (IC(50)=21.3 microM) and very potent antioxidant activity in the DPPH test (IC(50)=6 microM). In vivo, tiliroside significantly inhibited the mouse paw oedema induced by phospholipase A(2)(ED(50)=35.6 mg/kg) and the mouse ear inflammation induced by TPA (ED(50)=357 microg/ear). Pinocembrin was the only flavonoid that exhibited anti-inflammatory activity in the sheep red blood cell-induced delayed-type hypersensitivity reaction. However, only tiliroside significantly reduced the oedema and leukocyte infiltration induced by TPA. As in the case of other flavonoids, the anti-inflammatory activity of tiliroside could be based on its antioxidant properties, although other mechanisms are probably involved.

Anti-inflammatory and antioxidant properties of Helichrysum italicum

The anti-inflammatory and antioxidant activities of the aerial part of Helichrysum italicum extracts have been established in various in-vivo and in-vitro experimental models. The results obtained on the acute oedemas induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) and ethyl phenylpropiolate in the mouse ear, by serotonin and phospholipase A2 (PLA2) in the mouse paw, on chronic inflammation induced by repeated application of TPA in the mouse ear and on the delayed-type hypersensitivity induced by sheep red blood cells suggest that said anti-inflammatory activity is due to the effects of compounds expressed via a corticoid-like mechanism. In addition, the antioxidant activity of the extracts seems to be implicated in this anti-inflammatory activity, as the former inhibits enzymatic and non-enzymatic lipid peroxidation and has free-radical scavenger properties. We conclude that the anti-inflammatory activity of Helichrysum italicum can be explained by multiple effects, including inflammatory enzyme inhibition, free-radical scavenging activity and corticoid-like effects.

Oleanonic acid, a 3-oxotriterpene from Pistacia, inhibits leukotriene synthesis and has anti-inflammatory activity

One of the best known bioactive triterpenoids is oleanolic acid, a widespread 3-hydroxy-17-carboxy oleanane-type compound. In order to determine whether further oxidation of carbon 3 affects anti-inflammatory activity in mice, different tests were carried out on oleanolic acid and its 3-oxo-analogue oleanonic acid, which was obtained from Pistacia terebinthus galls. The last one showed activity on the ear oedema induced by 12-deoxyphorbol-13-phenylacetate (DPP), the dermatitis induced by multiple applications of 12-O-tetradecanoyl-13-acetate (TPA) and the paw oedemas induced by bradykinin and phospholipase A2. The production of leukotriene B4 from rat peritoneal leukocytes was reduced by oleanonic acid with an IC50 of 17 microM. Negligible differences were observed in the response of both triterpenes to DPP, bradykinin, and phospholipase A2, while oleanonic acid was more active on the dermatitis by TPA and on the in vitro leukotriene formation. In conclusion, the presence of a ketone at C-3 implies an increase in the inhibitory effects on models related to 5-lipoxygenase activity and on associated in vivo inflammatory processes.

Inhibition of T-cell invasion across cultured fibroblast monolayers by phenothiazine-related calmodulin inhibitors: impairment of lymphocyte motility by trifluoperazine and chlorpromazine, and alteration of the monolayer by pimozide

Phenothiazines inhibit the typical shape changes displayed by activated lymphocytes and thereby their migration through polycarbonate filters. The structure activity relationship of this effect is distinct from calmodulin inhibition. Our aim was to study this effect of phenothiazines on lymphocyte migration in an environment with living solid tissue cells. We assessed the effect of trifluoperazine and chlorpromazine (TFP and CP, two strong inhibitors of lymphocyte motility) and pimozide (PIM, a much weaker inhibitor of lymphocyte motility but a strong inhibitor of calmodulin) on invasion of human Molt-4 T-cells across precultured fibroblast monolayers. As expected invasion was inhibited by TFP and CP in the micromolar range that also inhibited motility. Surprisingly, PIM inhibited monolayer invasion at least as efficiently as TFP and CP (from 2.25 microM on). Preincubation of the monolayers or the lymphoid cells show that PIM exerted this novel invasion inhibiting effect on the monolayer. TFP and CP had a much weaker effect on the monolayer. Since these three compounds inhibit calmodulin in the same order, it is likely that this effect on the monolayer was caused by inhibition of a calmodulin-dependent pathway. KN-62, a specific inhibitor of calmodulin-dependent protein kinase II acted on the monolayer like PIM, whereas ML-7, a specific inhibitor of myosin regulatory light chain kinase, inhibited lymphoid cell motility like TFP and CP. In conclusion, invasion of T-cells across cellular monolayers is inhibited both by PIM and by phenothiazines like TFP and CP, but via distinct mechanisms: TFP and CP inhibit lymphocyte motility via a calmodulin independent pathway, whereas PIM impairs the monolayer's tolerance for invasion, most likely via a calmodulin and CamKII dependent pathway.