Amelioration of autoimmune arthritis by naringin through modulation of T regulatory cells and Th1/Th2 cytokines.

Naringin, a well-known flavanone glycoside found in grapefruit and other citrus fruits, was determined to be an effective anti-inflammatory compound. We investigated the effect of naringin on the key mediators of arthritic inflammation, namely T cell subsets, CD4(+)GITR(+) expressing cells, CD4(+)CD25(+)Foxp3(+) (Treg), Th1/Th2 cytokines and inflammatory mediators. We treated Balb/c mice (p.o.) with naringin (20, 40 and 80 mg/kg) for 14 days. Compared with the vehicle-treated and arthritic-control mice, the naringin treatment demonstrated a considerable decrease in the level of T cells, CD4(+)GITR(+), Th1 cytokine and inflammatory mediator expressions. In contrast, naringin treatment resulted in significantly up-regulated Treg and Th2 cytokine levels. Therefore, the naringin-induced inhibition of the T cells, various pro-inflammatory cytokines and inflammatory mediators that facilitate cellular infiltration into the joints might have contributed to its anti-arthritic activity. Our data suggest that naringin diminished the AIA in mice and it could be a potential alternative/adjunct treatment for RA.

Anti-inflammatory effect of Euphorbia hirta in an adjuvant-induced arthritic murine model.

Despite extensive research into inflammatory diseases to date, no drugs with favourable safety profiles are available for treatment. Euphorbia hirta (E. hirta) is a tree that is locally used as a traditional medicine in Africa and Australia to treat numerous diseases such as hypertension, antipyretic and anti-inflammatory activities. The aim of the present study was to determine the potential anti-arthritic effects of E. hirta in mouse models of adjuvant induced arthritis (AIA). We treated BALB/c mice with (p.o.) E. hirta (25, 50, 100, and 200 mg/kg) daily (13 days) beginning at the onset of AIA. We examined the effect of E. hirta on key mediators of arthritic-inflammation, including pro-inflammatory (IL-2, IFN-γ, and TNF-α) and anti-inflammatory (IL-4 and IL-5) cytokines, T-cell activation markers (CD25/CD69), and co-stimulatory molecules (CD80/CD86). We also examined the inflammatory mediators (PGE2 and LTB4) response. E. hirta-treated mice showed a substantial reduction in the levels of pro-inflammatory cytokines, down regulated cell activation markers and co-stimulatory molecules, and up regulated anti-inflammatory cytokines. E. hirta decreased the levels of inflammatory-mediators in AIA animals. Supplementation with an E. hirta extract may be a promising treatment for arthritic and inflammatory diseases.

Grape seed proanthocyanidin extract protects against carrageenan-induced lung inflammation in mice through reduction of pro-inflammatory markers and chemokine expressions.

Proanthocyanidins are the most abundant phenolic compounds and have been reported to exert anti-inflammatory actions. The aim of this study was to investigate the effects of grape seed proanthocyanidin extract (GSPE) in a mouse model of carrageenan-induced pleurisy. Following the induction of pleurisy using λ-carrageenan (Cg, 1 %), GSPE (25, 50 and 100 mg/kg) was administered per-oral (p.o.), and the glucocorticoid-induced tumour necrosis factor receptor (GITR), IL-17A expressing cells and other markers, such as cytokines (Th1/Th2 and Th17), were studied. We evaluate the effects of GSPE on the mRNA expression of pro-inflammatory and anti-inflammatory mediators. The results illustrated that the cell numbers of IL-17A and GITR expressing cells and the cytokine levels in Th1/Th17 cells were markedly increased in the Cg-group, whereas the cytokines produced by Th2 cells were significantly decreased in the same group. Treatment with GSPE reversed these effects. Histological examinations revealed anti-inflammatory effects of GSPE.

Grape seed proanthocyanidin extract has potent anti-arthritic effects on collagen-induced arthritis by modifying the T cell balance.

Rheumatoid arthritis (RA) is an autoimmune disease characterised by chronic inflammation of the synovial joints, joint malformations, and disability. The continuous use of conventional anti-inflammatory drugs is associated with severe adverse effects. Grape seed proanthocyanidin extract (GSPE) is considered to have protective effects against several diseases. In this study based on the mouse adjuvant-induced-arthritis (AIA) model, we examined the effects of GSPE on the key mediators of arthritic inflammation, namely T cell subsets, glucocorticoid-induced tumour necrosis factor receptor (GITR) expressing cells, CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells, Th17 cells, Th1/Th2 cytokines, and inflammatory mediator gene expression. We treated BALB/c mice with 25, 50, or 100 mg/kg GSPE or saline daily (14 days) per orally (p.o.) at the onset of AIA. At the peak phase of AIA (day 14), the heparinised whole blood and ankle joints of all groups were collected and tested. GSPE-treated mice showed a substantial reduction in the levels of T cell subsets, GITR-expressing cells, and Th1 cytokines as well as the inflammatory mediators (MCP-1, MIP-2, and ICAM-1) that induce them compared with the vehicle-treated (saline) and arthritic mice. However, GSPE significantly upregulated the number of Tregs and Th2 cytokine producing cell number or it also induced Th17/Treg rebalance and orchestrated various pro-inflammatory and anti-inflammatory cytokines and the gene expression of their mediators that mediate cellular infiltration into the joints. This might, contribute to its anti-arthritic activity. Our results suggest that p.o. treatment with GSPE attenuated AIA in mice might offer a promising alternative/adjunct treatment for RA.

TNF-α inhibitory effect of Euphorbia hirta in rats.

CONTEXT: Euphorbia hirta L. (Euphorbiaceae) (E. hirta) is a tree locally used as a traditional medicine in Africa and Australia to treat numerous diseases such as hypertension, respiratory ailments, tumors, and wounds, and it has reported antiallergic, antipyretic, anti-inflammatory activities, etc. OBJECTIVE: This study evaluated the ability of fresh leaves of E. hirta ethanol extract to inhibit the intracellular tumor necrosis factor α (TNF-α) level in the synovial fluid and neutrophils in lipopolysaccharide (LPS)-induced inflamed rat knees. MATERIALS AND METHODS: Female Wister albino rats 140-160 g were used. E. hirta ethanol extract was given orally at 25, 50, 100, and 200 mg/kg, 2 h before an intra-articular (i.a.) injection of LPS. Two and three hours later, synovial fluid and neutrophils levels of intracellular TNF-α production were measured. RESULTS: In the time course of the experiment, E. hirta maximum inhibition at 100 and 200 mg/kg (p.o.) dose showed 16.5 ± 1.34 and 14.4 ± 1.30% of synovial fluid, 4.26 ± 0.36 and 3.78 ± 0.29% of neutrophils levels of intracellular TNF-α productions at 2 h after LPS injection. LPS control displayed 22.97 ± 1.61 and 6.78 ± 0.34% of synovial fluid and neutrophils levels of intracellular TNF-α at 2 h after LPS injection. Intracellular TNF-α was also estimated at 3 h after LPS injection. DISCUSSION AND CONCLUSION: The LPS-injected rat knee model gives a comparative study of acute anti-inflammatory responses. E. hirta inhibition of proinflammatory intracellular cytokine TNF-α production with LPS-induced inflamed rat knee is of great importance in defining the anti-arthritic potential of E. hirta.

Immunosuppressive effects of Euphorbia hirta in experimental animals.

Euphorbia hirta L. (Euphorbiaceae) (E. hirta) is a tree locally used as a traditional medicine in Africa and Australia to treat numerous diseases such as hypertension, respiratory ailments, tumors, wounds, antipyretic, anti-inflammatory activities, etc. Therefore, we undertook to investigate their immunomodulatory effect on T lymphocytes (CD3+, CD4+ and CD8+ receptors) and Th1 cytokines (IL-2, TNF-α, IFN-γ) in a dose-dependent manner. E. hirta ethanol extract at 25, 50, 100 and 200 mg/kg doses was given orally for 7 days from the day of immunization. E. hirta maximum inhibition at 100 and 200 mg/kg p.o. was found to significantly block the production of the cell-mediated immune response, (CD3+, CD4+ and CD8+ receptors) and (IL-2, TNF-α, IFN-γ) and also prolongs graft rejection. E. hirta also showed a decrease of delayed hypersensitivity (DTH) response and dose-related decrease in the primary antibody response, respectively. Based on the data, it can be suggested that E. hirta is a potent and non-toxic immunosuppressor, which can be further explored for the development of potent immunosuppressor.

Modulation of Th1 cytokines and inflammatory mediators by Euphorbia hirta in animal model of adjuvant-induced arthritis.

Euphorbia hirta L. (Euphorbiaceae) (E. hirta) is a tree locally used as a traditional medicine in Africa and Australia to treat numerous diseases such as hypertension, respiratory ailments, tumors, antipyretic, anti-inflammatory activities. In the present study, we investigated the anti-arthritic activity of fresh leaves of E. hirta ethanol extract that was found to inhibit the production of inflammatory mediators and cytokines of adjuvant arthritis in rats. Adjuvant arthritis was induced in rats (Wistar) by the subplantar injection of 0.05 ml freshly prepared suspension (5.0 mg/ml) of steam killed Mycobacterium tuberculli in liquid paraffin. Animals were treated with graded doses of 25, 50, 100 and 200 mg/kg of E. hirta ethanol extract, p.o. E. hirta significantly inhibited the swelling of the adjuvant-induced arthritis. Moreover, E. hirta at higher dose (200 mg/kg) showed 40.54 ± 1.09 % of CD3+, 15.1 ± 0.76 % of CD4+, 12.2 ± 1.18 % of CD8+ T cell receptor and 17.6 ± 1.11 % gated of CD19+ B cell receptor revealing a down regulation of adjuvant-induced arthritis as compared to the corresponding valves of the arthritic control rats. According to the results shown in Tables 1, 2, the production of IL-1ß, TNF-α, IL-2 and IFN-γ were increased in splenocytes of arthritic rats and this increased level was reduced by E. hirta. Also, E. hirta significantly down regulated lipopolysaccharide (LPS)-induced production of nitric oxide production in peritoneal macrophages. These results suggest that E. hirta exhibits an improvement in adjuvant-induced arthritis through down regulation of activated macrophages and T lymphocytes functions. Such unique effects of E. hirta shown on adjuvant arthritis rat model may be advantageous to the long-term treatment of clinical rheumatoid arthritis. Table 1 Effect of E. hirta and prednisolone (Pred) on LPS-induced IL-1ß and TNF-α productions from splenocytes in Mycobacterium tuberculli-induced inflammatory arthritic rats Treatment Dose (mg/kg) IL-1ß (pg/ml) TNF-α (pg/ml) Arthritic control (AC) - 323.56 ± 31.65 180.91 ± 24.12 E. hirta 25 311.19 ± 29.08* 171.43 ± 22.54* E. hirta 50 287.12 ± 26.98* 164.54 ± 21.76** E. hirta 100 243.12 ± 19.21*** 157.30 ± 18.54*** E. hirta 200 215.21 ± 16.05*** 138.43 ± 17.98*** Prednisolone (Pred) 5 187.18 ± 15.21*** 123.77 ± 15.12*** Normal control (NC) - 54.12 ± 12.54 71.94 ± 12.12 Each value indicates the mean ± SEM of six animals AC arthritic control, NC normal control; E. hirta (25, 50, 100 and 200 mg/kg) and prednisolone (5 mg/kg) were given p.o. from day 0 to day 21 after Mycobacterium tuberculli injection, respectively * p < 0.05; ** p < 0.01; *** p < 0.001, compared to arthritic control Table 2 Effect of E. hirta and Prednisolone (Pred) on Con A-induced IL-2 and IFN-γ productions from splenocytes in Mycobacterium tuberculli-induced inflammatory arthritic rats Treatment Dose (mg/kg) IL-2 (pg/ml) IFN-γ (pg/ml) Arthritic control (AC) - 235.98 ± 15.23 165.95 ± 13.87 E. hirta 25 225.12 ± 14.76** 154.76 ± 11.07** E. hirta 50 207.76 ± 13.87** 134.76 ± 11.01** E. hirta 100 189.98 ± 12.65 *** 110.64 ± 10.98*** E. hirta 200 157.84 ± 14.32 *** 98.54 ± 10.76*** Prednisolone (Pred) 5 131.08 ± 13.31*** 87.65 ± 10.61*** Normal control (NC) - 78.12 ± 12.04 31.87 ± 10.12 Each value indicates the mean ± SEM of six animals AC arthritic control, NC normal control; E. hirta (25, 50, 100 and 200 mg/kg) and prednisolone (5 mg/kg) were given p.o. from day 0 to day 21 after Mycobacterium tuberculli injection, respectively * p < 0.05; ** p < 0.01; *** p < 0.001, compared to arthritic control.

L-Carnitine halts apoptosis and myelosuppression induced by carboplatin in rat bone marrow cell cultures (BMC).

Carboplatin (CP), a second generation platinum compound, is effective against various types of cancers, producing less nephrotoxicity and ototoxicity but more myelotoxicity than cisplatinum. CP-myelosuppression is the rate-limiting step of its clinical use. Prevention of CP-myelosuppression is a major target in the field of chemotherapy. Therefore, the present study investigates the use of L-carnitine (LCR)-an antioxidant, cardioprotective, neuroprotective, and immunostimulant nontoxic natural compound-to protect against CP-induced myelosuppression. The viability of BMC was studied using a trypan blue exclusion technique following incubation with CP and/or LCR as a function of time and concentration. Apoptosis was tested for by detecting the amount of DNA fragmentation and the visualization of DNA ladders upon gel electrophoresis. Bone marrow progenitor cell function was examined by colony forming unit assay. Cellular contents of glutathione (GSH) and malondialdehyde (MDA) were also estimated. Results revealed that LC50 of CP is 4.7 mM and the highest safe concentration of LCR is 5 mM. Co-exposure of LCR+CP rescued BMC viability by 37% compared to the CP-treated cultures. The LCR halts CP-induced apoptosis and it significantly improves the function of the bone marrow progenitors by increasing the number of colony-forming units as a response to granulocyte/macrophage colony stimulating factors. Finally, LCR restores CP-induced GSH depletion and prevents MDA elevation in BMC. In summary, the results suggest that LCR is able to protect against CP-induced myelosuppression, which suggests its use as an adjuvant therapy. This finding merits further investigation into the mechanism(s) of such protection as well as its interaction with CP antitumor activity.

Treatment of experimental osteomyelitis by liposomal antibiotics.

OBJECTIVES: Traditional antibiotic therapy of staphylococcal osteomyelitis by a single drug or a drug combination is ineffective in producing complete sterilization of infected bones. The aim of this study was to develop a non-traditional delivery system of antibiotics for treatment of chronic experimental osteomyelitis. METHODS: In the current work, ciprofloxacin and vancomycin were encapsulated in a cationic, anionic or neutral liposomal formulation. For prolonged circulation in serum, liposomal dispersions (<100 nm in diameter) were sonicated for different times (20, 40, 60 or 80 s), and tested for antibacterial activities. RESULTS AND CONCLUSIONS: Liposomes sonicated for 40 s gave the highest antibacterial activities in vitro. Since cationic liposomes trapped the highest percentage of antibiotics, and enhanced antibacterial activity above that of the free drugs, they were used for therapeutic trials to treat chronic staphylococcal osteomyelitis induced in rabbits. Therapeutic trials with antibiotics given intravenously revealed that, free ciprofloxacin or vancomycin given alone for 14 days was ineffective in sterilizing bone. Combination therapy with free ciprofloxacin and vancomycin for 14 days was more effective. However, this group showed renal dysfunction and severe diarrhoea, which resulted in loss of 33.3% of treated animals. Treatment with liposomal forms of either drug for 7 days was ineffective. Meanwhile, combination therapy in liposomal form for 7 days was more effective. Complete sterilization of bone tissues on cultures (100% cure) was obtained only in the group treated for 14 days with the combination of both drugs in liposomal form. Moreover, liposomal formulations showed much lower nephrotoxicity and a lower incidence of severe diarrhoea than that induced by free drugs.