Cyclosporine differentially regulates interleukin-10, interleukin-15, and tumor necrosis factor a production by rheumatoid synoviocytes

Eugenol mimics exercise to promote skeletal muscle fiber remodeling and myokine IL-15 expression by activating TRPV1 channel

Metabolic disorders are highly prevalent in modern society. Exercise mimetics are defined as pharmacological compounds that can produce the beneficial effects of fitness. Recently, there has been increased interest in the role of eugenol and transient receptor potential vanilloid 1 (TRPV1) in improving metabolic health. The aim of this study was to investigate whether eugenol acts as an exercise mimetic by activating TRPV1. Here, we showed that eugenol improved endurance capacity, caused the conversion of fast-to-slow muscle fibers, and promoted white fat browning and lipolysis in mice. Mechanistically, eugenol promoted muscle fiber-type transformation by activating TRPV1-mediated CaN signaling pathway. Subsequently, we identified IL-15 as a myokine that is regulated by the CaN/nuclear factor of activated T cells cytoplasmic 1 (NFATc1) signaling pathway. Moreover, we found that TRPV1-mediated CaN/NFATc1 signaling, activated by eugenol, controlled IL-15 levels in C2C12 myotubes. Our results suggest that eugenol may act as an exercise mimetic to improve metabolic health via activating the TRPV1-mediated CaN signaling pathway.

Boswellia serrata normalizes altered haematological indices, attenuates pain and inflammation associated with adjuvant induced arthritis in rats

A study was carried out to evaluate the anti-arthritic potential of Boswellia serrata on haematological parameters, pain and inflammation associated with adjuvant induced rheumatoid arthritis in rats. Thirty male Wistar rats were randomly divided in to 5 groups. While Group 1 served as normal control, Group 2 served as arthritic control, Groups 3, 4 and 5 served as treatment groups. Arthritis was induced in animals from Groups 2 to 5 with 0.1 ml of Freund's complete adjuvant injected intradermally into the foot pad of hindlimbs. Consequently, the onset of rheumatoid arthritis was indicated by hyperalgesia and inflammatory signs which were assessed by paw volume, paw diameter and paw withdrawal latency. Treatment protocol was followed from 3rd to 21st day, with Boswellia serrata given orally as methanolic extract at 500 mg/kg b.wt. to Group 3, meloxicam given subcutaneously at 1 mg/kg b.wt to Group 4 and both the drugs given concurrently to Group 5. The drug effects were evaluated on paw parameters and haematological indicators to depict the extent of paw inflammation and its subsequent amelioration. Conclusively, a major curative effect was witnessed with Boswellia serrata when compared to meloxicam.

Tacrolimus Improves the Implantation Rate in Patients with Elevated Th1/2 Helper Cell Ratio and Repeated Implantation Failure (RIF)

Introduction An abnormal endometrial immune response is involved in the pathogenesis of repeated implantation failure (RIF), so we investigated the effectiveness of tacrolimus treatment on the endometrium of RIF patients.

Materials and Methods Ten RIF patients with elevated T-helper 1/T-helper 2 (Th1/Th2) cell ratios were recruited into a clinical study. The expression of p53, leukemia inhibitory factor (LIF), interleukin (IL)-4, IL-10, IL-17, and interferon gamma (IFN-γ) in the endometrium of patients with and without tacrolimus treatment and the association of these factors with assisted reproductive technology (ART) outcomes were investigated.

Results Tacrolimus significantly increased the expression of LIF, IL-10, and IL-17 and decreased the expression of IL-4, IFN-γ, and the IFN-γ/IL-10 ratio in RIF patients. Tacrolimus treatment resulted in an implantation rate of 40%, a clinical pregnancy rate of 50%, and a live birth rate of 35% in RIF patients with elevated Th1/Th2 ratios who had previously failed to become pregnant despite at least three transfers of embryos. We also found a significant positive correlation between IL-10 levels and the implantation rate.

Conclusions Our findings suggest that RIF patients with a higher Th1/Th2 ratio could be candidates for tacrolimus therapy and that this immunosuppressive drug could be acting through upregulation of LIF, IL-10, and IL-17.

Cyclosporine: A Historical Perspective on Its Role in the Treatment of Noninfectious Uveitis

The history of cyclosporine and uveitis is intertwined with the development of experimental autoimmune uveitis (EAU) animal models and the understanding that T lymphocytes play a major role in the pathogenesis of uveitis. The early studies of CsA in uveitis also demonstrated the power of collaborative efforts in translational research. Dr. Robert Nussenblatt and his colleagues were the first to show that CsA can inhibit EAU. Over many years after the initial CsA experiments, Dr. Nussenblatt's group as well as others continued to study CsA under experimental conditions as well as in clinical trials with human patients. The data and observations from these studies significantly advanced our knowledge of uveitis pathophysiology and demonstrated the value of well-designed masked, controlled treatment trials in uveitis. Dr. Nussenblatt and his collaborators delved into the most significant adverse effect of CsA, renal toxicity, and helped elucidate the pathophysiology of renal injury. They explored adjunctive treatments to improve the efficacy and decrease the toxicity of CsA and also studied other members of the cyclosporine family. Among the immunosuppressives used to treat ocular inflammation, CsA was the first, and remains the only medication comprehensively studied under both experimental and clinical conditions.

Relationship of Interleukin-10 and Transforming Growth Factor-β Levels With Short-Term Graft Function After Kidney Transplantation

INTRODUCTION

We evaluated the relationship of interleukin-10 (IL-10) and transforming growth factor-β (TGF-β) levels with graft function in kidney transplantation patients receiving tacrolimus-based immunosuppression during the early post-transplantation period.

MATERIAL AND METHODS

There were 112 patients who underwent kidney transplantation from live donors between May 2011 and May 2013. Eight patients had at least 1 of the exclusion criteria, and the remaining 104 patients were included in the study. The recipients underwent evaluation for biochemical markers, complete blood count, and creatinine and cytokine (IL-10, TGF-β) levels during the pretransplantation and post-transplantation 6 months.

RESULTS

The creatinine level was negatively correlated with IL-10 and positively correlated with TGF-β levels in both the pretransplantation and early post-transplantation period.

CONCLUSION

Low serum TGF-β and high IL-10 levels at post-transplantation month 6 might have a positive effect on graft survival in living donor kidney recipients on tacrolimus-based immunosuppressive treatment.

IL-15 is decreased upon CsA and FK506 treatment of acute rejection following heart transplantation in mice

The aim of this study was to investigate the effect of cyclosporine A (CsA) and tacrolimus (FK506) on interleukin-15 (IL-15) production during acute rejection following heart transplantation in mice. Inbred male Balb/c (H‑2d) and C57BL/6 (H-2b) mice were used to establish a heterotopic intra-abdominal cardiac transplantation model. The mice were divided in four groups: syngeneic control, allogeneic acute rejection, allogeneic rejection treated with CsA, and allogeneic rejection treated with FK506. The expression of IL-15, IL-2, and tumor necrosis factor-α (TNF-α) was measured using reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. A low level of IL-15 was detected in transplanted hearts of the control group, with a significant increase observed in the allogeneic acute rejection group. Compared to the allogeneic acute rejection group, IL-15 expression was significantly decreased in the CsA- and FK506-treated allogeneic rejection groups. The TNF-α expression pattern was similar to that of IL-15 in all groups. IL-2 expression was increased in the allogeneic acute rejection group and was inhibited in mice treated with CsA and FK506. In conclusion, increased IL-15 expression in rejected murine heart grafts may be reduced by CsA and FK506 in vivo.

NFAT gene family in inflammation and cancer

Calcineurin-NFAT signaling is critical for numerous aspects of vertebrate function during and after embryonic development. Initially discovered in T cells, the NFAT gene family, consisting of five members, regulates immune system, inflammatory response, angiogenesis, cardiac valve formation, myocardial development, axonal guidance, skeletal muscle development, bone homeostasis, development and metastasis of cancer, and many other biological processes. In this review we will focus on the NFAT literature relevant to the two closely related pathological systems: inflammation and cancer.

TWEAK promotes osteoclastogenesis in rheumatoid arthritis

Bone destruction is critical in the functional disability of patients with rheumatoid arthritis (RA). Osteoclasts, specialized bone-resorbing cells regulated by cytokines, such as receptor activator of NF-κB ligand (RANKL), are primarily implicated in bone destruction in RA. The aim of the study was to examine whether tumor necrosis factor-like weak inducer of apoptosis (TWEAK), a member of the tumor necrosis factor superfamily, has osteoclastogenic activity in patients with RA and in animal models, including mice with collagen-induced arthritis (CIA) and IL-1 receptor antagonist knockout (IL-1RaKO) mice. TWEAK was increased in the synovium, synovial fluid, and serum of patients with RA and in the synovium of CIA mice and IL-1RaKO mice. TWEAK induced RANKL expression in mixed joint cells and splenocytes from CIA mice, IL-1RaKO mice, and fibroblast-like synoviocytes from patients with RA. Both osteoclast precursor cells and osteoclasts express TWEAK receptor fibroblast growth factor-inducible 14. In addition, TWEAK enhanced in vitro osteoclastogenesis without the presence of RANKL-providing cells and by inducing RANKL expression in fibroblast-like synoviocytes. Moreover, treatment with fibroblast growth factor-inducible 14-Fc inhibited RANKL-induced osteoclastogenesis, indicating that endogenous TWEAK also has osteoclastogenic activity. Our data demonstrated that TWEAK promotes osteoclastogenesis in RA, suggesting that therapeutic strategies targeting TWEAK could be effective for treatment of patients with RA, especially in preventing bone destruction.

Cyclosporine in anti-Jo1-positive patients with corticosteroid-refractory interstitial lung disease

OBJECTIVE

To describe the longterm effectiveness and safety of cyclosporine (CYC) in patients with anti-Jo1-positive antisynthetase syndrome with corticosteroid-refractory interstitial lung disease (ILD).

METHODS

All patients with anti-Jo1 antisynthetase syndrome referred to our division between June 1991 and February 2010 were retrospectively evaluated for ILD. ILD was assessed using pulmonary function tests (PFT) and/or high-resolution computed tomography (HRCT). Kazerooni score was used to evaluate the HRCT extent of ILD. Prednisone was the first-line treatment in all cases (1 mg/kg/day orally, then tapering). Patients with corticosteroid-refractory or relapsing ILD were then included in this retrospective study. All patients started CYC (3 mg/kg/day) without increasing prednisone dosage. Both PFT and chest HRCT were regularly reassessed during followup.

RESULTS

Over the period of study we evaluated 18 patients with antisynthetase syndrome; 17 had ILD (13 women; median age at ILD onset 57 yrs); all patients failed prednisone within 12 months of ILD onset and subsequently started CYC. The median followup on CYC was 96 months [interquartile range (IQR) 57-120 mo]. Upon starting CYC, median forced vital capacity (FVC) was 60% (IQR 56%-70%), median DLCO 60% (IQR 50%-62.75%), and median Kazerooni score 16 (IQR 7-18). After 1 year of CYC, FVC (p = 0.0006), DLCO (p = 0.0010), and total Kazerooni score (p = 0.0002) improved and prednisone was tapered (median reduced from 25 mg/day to 2.5 mg/day; p < 0.0001). The results were substantially maintained including at last available followup. CYC side effects were hypertension (5 patients) and creatinine increase (6 patients). CYC was reduced in 3 cases and withdrawn in 4. Three out of 4 patients who interrupted CYC experienced ILD relapse; 2 patients recommenced low-dose CYC with subsequent ILD control. One patient refused re-treatment and subsequently died.

CONCLUSION

CYC is effective and substantially safe in patients with anti-Jo1 antisynthetase syndrome with corticosteroid-refractory ILD. CYC withdrawal may be associated with ILD relapse, and low-dose CYC was effective in ILD control.

Grape-seed proanthocyanidin extract as suppressors of bone destruction in inflammatory autoimmune arthritis

Chronic autoimmune inflammation, which is commonly observed in rheumatoid arthritis (RA), disrupts the delicate balance between bone resorption and formation causing thedestruction of the bone and joints. We undertook this study to verify the effects of natural grape-seed proanthocyanidin extract (GSPE), an antioxidant, on chronic inflammation and bone destruction. GSPE administration ameliorated the arthritic symptoms of collagen-induced arthritis (CIA), which are representative of cartilage and bone destruction. GSPE treatment reduced the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells and osteoclast activity and increased differentiation of mature osteoblasts. Receptor activator of NFκB ligand expression in fibroblasts from RA patients was abrogated with GSPE treatment. GSPE blocked human peripheral blood mononuclear cell-derived osteoclastogenesis and acted as an antioxidant. GSPE improved the arthritic manifestations of CIA mice by simultaneously suppressing osteoclast differentiation and promoting osteoblast differentiation. Our results suggest that GSPE may be beneficial for the treatment of inflammation-associated bone destruction.

The use of cyclosporine-A in dogs with chronic osteoarthritis: a pilot study

OBJECTIVE

To evaluate the efficacy of cyclosporine-A in dogs with radiographic and physical evidence of chronic stifle osteoarthritis.

MATERIALS AND METHODS

Ten hound-type dogs with osteoarthritis induced by surgical transection of a cranial cruciate ligament followed by immediate stabilization of the stifle four years prior to study start were randomized to two groups. Cyclosporine-A was administered orally once daily at 5 mg/kg to one group for one month while the other group served as control. After a two week wash-out period during which the animals were not treated, and the degree of lameness was allowed to return to baseline, the treatments were switched so that the second group received treatment with cyclosporine-A and the first group served as control. Ground reaction forces were measured using a force platform in all animals at day zero and then every two weeks until the end of the study.

RESULTS

Cyclosporine-A did not alter the degree of lameness based on assessment of ground reaction forces.

CONCLUSIONS

At a dose of 5 mg/kg/day for 28 days, cyclosporine-A was not effective in decreasing lameness of dogs with chronic osteoarthritis induced by surgical transection of the cranial cruciate ligament.

The B cell, arthritis, and the sympathetic nervous system

The pathogenesis of rheumatoid arthritis (RA) is still an unresolved puzzle. Many factors and inflammatory cells play together to initiate a chronic inflammatory process that, if untreated, leads to complete destruction of involved joints. Recent success in treating severe forms of RA with B cell-depleting or -modifying agents revived the concept that the B cell might play a pivotal role in the pathogenesis of some forms of arthritis. However, the rather unspecific treatment approach affecting all B cells, no matter if autoreactive or not, leads to potential harmful side-effects, e.g., severe infections. Therefore, finding regulatory systems that more specifically modulate B cell function is important to improve current treatment options. One such regulatory system is the sympathetic nervous system (SNS), which is known to modulate B cell function, but also profoundly influences arthritis development and severity. This review develops the hypothesis that the SNS via modulating B cell function influences arthritis development and progression. For this purpose data is presented that shows (1) how the SNS influences B cell function, (2) how the SNS influences arthritis development and severity, and (3) how B cells are involved in the disease process with an emphasis on possible contact points for SNS neuromodulation.

Transcriptional regulation of bone and joint remodeling by NFAT

Osteoporosis and arthritis are highly prevalent diseases and a significant cause of morbidity and mortality worldwide. These diseases result from aberrant tissue remodeling leading to weak, fracture-prone bones or painful, dysfunctional joints. The nuclear factor of activated T cells (NFAT) transcription factor family controls diverse biologic processes in vertebrates. Here, we review the scientific evidence that links NFAT-regulated gene transcription to bone and joint pathology. A particular emphasis is placed on the role of NFATs in bone resorption and formation by osteoclasts and osteoblasts, respectively. In addition, emerging data that connect NFATs with cartilage biology, angiogenesis, nociception, and neurogenic inflammation are explored. The goal of this article is to highlight the importance of tissue remodeling in musculoskeletal disease and situate NFAT-driven cellular responses within this context to inspire future research endeavors.

CD44 costimulation promotes FoxP3+ regulatory T cell persistence and function via production of IL-2, IL-10, and TGF-beta

Work by our group and others has demonstrated a role for the extracellular matrix receptor CD44 and its ligand hyaluronan in CD4(+)CD25(+) regulatory T cell (Treg) function. Herein, we explore the mechanistic basis for this observation. Using mouse FoxP3/GFP(+) Treg, we find that CD44 costimulation promotes expression of FoxP3, in part through production of IL-2. This promotion of IL-2 production was resistant to cyclosporin A treatment, suggesting that CD44 costimulation may promote IL-2 production through bypassing FoxP3-mediated suppression of NFAT. CD44 costimulation increased production of IL-10 in a partially IL-2-dependent manner and also promoted cell surface TGF-beta expression. Consistent with these findings, Treg from CD44 knockout mice demonstrated impaired regulatory function ex vivo and depressed production of IL-10 and cell surface TGF-beta. These data reveal a novel role for CD44 cross-linking in the production of regulatory cytokines. Similar salutary effects on FoxP3 expression were observed upon costimulation with hyaluronan, the primary natural ligand for CD44. This effect is dependent upon CD44 cross-linking; while both high-molecular-weight hyaluronan (HA) and plate-bound anti-CD44 Ab promoted FoxP3 expression, neither low-molecular weight HA nor soluble anti-CD44 Ab did so. The implication is that intact high-molecular weight HA can cross-link CD44 only in those settings where it predominates over fragmentary LMW-HA, namely, in uninflamed tissue. We propose that intact but not fragmented extracellular is capable of cross-linking CD44 and thereby maintains immunologic tolerance in uninjured or healing tissue.

cAMP regulates IL-10 production by normal human T lymphocytes at multiple levels: a potential role for MEF2

Signal transduction by the cAMP/cAMP-dependent protein kinase A (PKA) pathway is triggered through multiple receptors and is important for many processes in a variety of cells. In T cells, the engagement of the TCR-CD3 complex induces cAMP, a second messenger that controls immune response. IL-10, produced by a variety of lymphocyte subpopulations, is an important regulator of this response exerting a wide range of immunomodulatory actions. Elevation of cAMP has been shown to increase IL-10 production by monocytes. However, the mechanism of cAMP mediated regulation of IL-10 production by T lymphocytes remains unclear. In this study using normal peripheral T lymphocytes stimulated either through the TCR-CD3 complex or the TCR-CD3 and the CD28 molecule, we show that IL-10 is produced mainly by memory T lymphocytes after either way of stimulation and is drastically inhibited (70-90%) by cAMP elevating agents. cAMP mediated inhibition was reversed by the use of the specific PKA inhibitor Rp-8-Br-cAMP but not by the addition of exogenous rhIL-2, indicating that the inhibitory effect depends on PKA activation and is not secondary to IL-2 inhibition. Inhibition is taking place at both transcriptional and posttranscriptional level. Transfection of a luciferase reporter plasmid carrying the IL-10 promoter in T cells, revealed that TCR/CD28-induced activation was inhibited by 60% by cAMP elevation. The most sensitive part to cAMP mediated inhibition was a fragment of 135 bp upstream of TATA box, which contains multiple binding sites for MEF-2. Overexpression of MEF-2 in the same cells increased IL-10 promoter activity by 2.5-fold. Stimulation through TCR/CD28 increased MEF-2 binding in its corresponding binding sites which was inhibited by 80% in the presence of cAMP elevating agents. These results suggest that the inhibitory effect of cAMP on IL-10 production by normal peripheral T lymphocytes is cell type and stimulus specific, exerted on multiple levels and involves MEF2 transcription factor.

Design of a New Line in Treatment of Experimental Rheumatoid Arthritis by Artesunate

This study was aimed to evaluate the therapeutic potency of a new antimalarial drug, artesunate, in an experimental model of rheumatoid arthritis. Collagen-induced arthritis (CIA) was induced in Lewis rats.The intraperitoneally administration of artesunate (ARS) and methotrexate (MTX) were started on day 25 postimmunization and continued until final assessment on day 35. During this period, clinical examination was intermittent. The anticollagen type II antibody (CII Ab) and nitric oxide synthesis were measured. The paws and kness were then removed for histopathology and radiography assay. The biocompatibility of ARS and MTX were assessed using fibrosarcoma cell line. Our results showed that i.p. injection of artesunate to arthritic rats induced a significant reduction in paw edema. This beneficial effect was associated with a significant decrease in anti-CII antibody response compared with untreated rats. Histopathological assessment showed reduced inflammatory cells infiltrate in joints of treated rats, and tissue edema and bone erosion in the paws were markedly reduced following ARS therapy. Moreover, our radiographic results paralleled histological findings. Cytotoxicity analysis of ARS showed greater tolerability compared with MTX. Treatment with ARS significantly diminished nitric oxide formation in treated rats compared with untreated controls. Our findings revealed the therapeutic efficacy of artesunate in experimental rheumatoid arthritis compared with a choice drug (methotrexate). This result may recommend it as a second-line drug in the treatment of rheumatoid arthritis.

Release of heat shock protein 70 and the effects of extracellular heat shock protein 70 on the production of IL-10 in fibroblast-like synoviocytes

It has recently been suggested that heat shock protein (Hsp) 70, an intracellular protein, can be released into the extracellular compartment and exert important immunomodulatory functions. Although elevated Hsp70 has been found in synovial fluid from patients with rheumatoid arthritis (RA), its sources and extracellular functions remain unclear. In this study, we explored whether stress response such as heat stress or exposure to tumor necrosis factor-alpha (TNF-alpha) could induce Hsp70 release from RA fibroblast-like synoviocytes (FLSs) and whether extracellular Hsp70 would stimulate cytokine production in RA FLSs. Cultured FLSs were obtained from patients with RA. The expression of intracellular Hsp70 was studied by Western blot. Hsp70 release and the production of interleukin (IL)-6, IL-8, and IL-10 by RA FLSs were studied by specific enzyme-linked immunosorbent assays. The levels of Toll-like receptor (TLR) 2 and 4 mRNA and protein in FLSs were analyzed using reverse transcription-polymerase chain reaction and Western blotting. Treatment with sublethal heat shock or TNF-alpha results in the up-regulation of intracellular Hsp70 in FLSs and Hsp70 release from RA FLSs. In vitro studies show that extracellular Hsp70 can induce anti-inflammatory cytokine IL-10 production in FLSs. The mRNA and protein expression of TLR2 and TLR4 was demonstrated in FLSs, and TLR4 blocking abrogated the up-regulatory effects of Hsp70 on IL-10 production. Thus, these results lend support to the hypothesis that Hsp70 is actively released from FLSs in response to heat shock or TNF-alpha and Hsp70 may be a major paracrine/autocrine inducer of IL-10 production in FLSs via TLR4.

T cells are involved in the development of arthritis induced by anti-type II collagen antibody

T cells play an important role in initiating autoimmune responses and maintaining synovial inflammation in rheumatoid arthritis. Although, anti-type II collagen antibody-induced arthritis (CAIA) is generally believed to be a T cell- and B cell-independent model, the detailed pathogenesis of CAIA remains unclear. In the present study, to elucidate the contribution of T cells to the pathogenesis of CAIA, we evaluated the effects of CTLA4 Ig and cyclosporin (CsA). Arthritis was induced in mice by intravenous injection of anti-type II collagen antibody followed by intraperitoneal injection of lipopolysaccharide. CTLA4 Ig was intraperitoneally administered and CsA was subcutaneously administered; then the severity of arthritis was evaluated by scoring the edema and erythema of paws and by measuring hind paw thickness. Paw samples were collected 12 days after the antibody injection, and the mRNA expression levels were analyzed by real-time quantitative polymerase chain reaction. Administration of CTLA4 Ig ameliorated the increases in arthritic score and paw thickness in the later phase, but not in the early phase of arthritis. CsA suppressed the increases in arthritic score and paw thickness in both the early and later phases of arthritis. CTLA4 Ig and CsA suppressed mRNA up-regulation of T-cell markers, CD3 and CD25, and immune response-related mediators, IFN-gamma and IL-12. They also suppressed the up-regulation of macrophage marker, F4/80, and proinflammatory cytokines, TNF-alpha, IL-1beta and IL-6. The results provide direct evidence that arthritis in this model is T-cell activation dependent.

Cyclosporine and tacrolimus for the treatment of rheumatoid arthritis

PURPOSE OF REVIEW

The calcineurin inhibitors cyclosporine and tacrolimus are important treatments for patients with active rheumatoid arthritis, especially in cases of resistance or intolerance to methotrexate or other disease-modifying antirheumatic drugs. Here, we discuss the mechanism, efficacy and safety of cyclosporine and tacrolimus in the treatment of rheumatoid arthritis.

RECENT FINDINGS

Recent clinical trials of cyclosporine have shown the advantages of its combination with methotrexate, glucocorticoids and leflunomide in the treatment of active rheumatoid arthritis. In Japan, tacrolimus monotherapy was found to be quite effective and combination therapy with methotrexate had positive results in an American study. The inhibitory effects of both drugs not only on T lymphocytes, but also on human osteoclast formation, have been demonstrated in basic studies.

SUMMARY

Cyclosporine and tacrolimus are clinically available disease-modifying antirheumatic drugs. Numerous clinical studies have shown the usefulness of these calcineurin inhibitors in monotherapy and also when combined with methotrexate. Although these drugs have similar effects, there are some differences in adverse reactions.

Cyclosporine A inhibits IL-15-induced IL-17 production in CD4+ T cells via down-regulation of PI3K/Akt and NF-kappaB

Cyclosporine A (CSA) has various biological effects on T cells, including inhibition of interleukin (IL)-15-induced IL-17 production in CD4+ T cells from patients with rheumatoid arthritis (RA). However, the mechanism underlying this effect is not fully understood. Here, we tried to investigate the mechanism of CSA to inhibit IL-17 production induced by IL-15 in CD4+ T cells. Synovial fluid and serum levels of IL-15 and IL-17 were determined by ELISA. CD4+ T cells from RA patients were treated with IL-15 in the presence of CSA or several signal inhibitors. The concentration of IL-17 in culture supernatants was measured by ELISA and IL-17 mRNA expression was determined by RT-PCR. NF-kappaB binding activity for IL-17 transcription was assessed by electrophoretic mobility shift assay. IL-15 induced IL-17 production by CD4+ T cells in dose- and time-dependent manner. IL-15-stimulated IL-17 production and mRNA expression were inhibited by CSA in CD4+ T cells. Moreover PI3K/Akt inhibitor, NF-kappaB inhibitor, and FK506 significantly inhibited IL-15-induced IL-17 production in CD4+ T cells. Inhibition studies revealed the requirement of PI3K/Akt and NF-kappaB signal pathway for IL-15-induced IL-17 production. CSA down-regulated the phosphorylation of Akt and IkappaB. CSA inhibited binding of NF-kappaB to IL-17 promoter. The inhibitory effect of CSA on IL-15 induced IL-17 production partially depended on the increase in IL-10, since neutralizing anti-IL-10 antibodies were able to partially reverse this inhibition. CSA inhibits IL-17 production by CD4+ T cells and this effect is mediated by IL-15-activated NF-kappaB pathway in CD4+ T cells, which is possible mechanism of CSA in treating RA as NF-kappaB targeting strategy.

Effects and mechanisms of Clematis mandshurica Maxim. as a dual inhibitor of proinflammatory cytokines on adjuvant arthritis in rats

Effect and mechanism of Clematis mandshurica Maxim. water extract (CMA), a dual inhibitor of interleukin-1 (IL-1) and tumor necrosis factor-α (TNF-α), on rat adjuvant arthritis (AA) were investigated. Complete Freund's adjuvant (CFA) was used to induce AA in rats. The extents of inflammation and treatment response were evaluated with regard to lymphocyte proliferation. Serial evaluation was carried out on days 1, 7, 14, 21 and 28 after creation of inflammation. The lymphocyte proliferation study revealed cellular immunosuppression during the early phase of the disease. Administration of CMA on the same day or 5 days prior to inflammatory insult into the joint significantly reduced the inflammation as compared to the untreated animals in a dose dependent manner. The administration of CMA (2, 5 and 10mg/kg, subcutaneously (s.c.)) inhibited the inflammatory response and restored the weight of body and immune organs of AA rats. Synoviocytes proliferation of AA rats significantly increased, and the levels of TNF-α and IL-1 in supernatants of synoviocytes in AA rats were also elevated compared with the nonimmunized rats group. The administration of CMA (2, 5 and 10mg/kg, s.c.) reduced the above changes significantly. In contrast to TNF-α and IL-1, IL-10 production and the level of its mRNA of synoviocytes in AA rats were apparently decreased. CMA (2, 5 and 10mg/kg, s.c.) markedly increased IL-10 in synoviocytes at protein and transcription level. The results indicated that CMA had a beneficial effect on rats AA due to modulating inflammatory cytokines production of synoviocytes, which played a crucial role in pathogenesis of this disease.

Effect of cyclosporin a eye drop on keratoconjunctivitis sicca and its mechanism

In this study, the effect of cyclosporin A (CsA) eye drop on keratoconjunctivitis Sicca (KCS) and its mechanism were studied. The KCS models were established by injecting Pertussis vaccine, complete Freund's adjuvant (CFA) and antigen of conjunctiva from isotype mice. Then the KCS models were treated with cyclosporin A eye drop. Changes in breaking-up time (BUT), lacrimal secretion in 30 min and diversion in 24 h were measured. The percentage of beaker cells, the lymphocytic infiltration in conjunctiva were observed. The expression levels of Aquaporin-3 (AQP3) in conjunctiva epithelial cells, beaker cells and accessory lacrimal gland were immunohistochemically detected. The results showed that there were significant differences in BUT, the percentage of beaker cells, lacrimal secretion in 30 min, the lymphocytic infiltration and the expression of AQP3 between the experimental group and an control group. It was concluded that CsA eye drop exerts marked therapeutic effect on KCS by inhibiting T lymph cells, increasing the goblet cells and AQP3 expression in conjunctiva.

Effects and mechanisms of FR167653, a dual inhibitor of interleukin-1 and tumor necrosis factor, on adjuvant arthritis in rats

Effects and mechanisms of FR167653, 1-[7-(4-fluorophenyl)-1,2,3,4-tetrahydro-8-(4-pyridyl)pyrazolo[5,1-c][1,2,4] triazin-2-yl]-2-phenylethanedione sulfate monohydrate, a dual inhibitor of interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha), on rat adjuvant arthritis (AA) was investigated. Complete Freund's adjuvant was used to induce AA in rats. Secondary paw swelling of AA rats was measured, and polyarthritis index was scored. Synoviocytes were separated by the method of collagenase and DNase digestion. Synoviocytes proliferation was assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. TNF-alpha, IL-1 and interleukin-10 (IL-10) production of synoviocytes was measured with ELISA. The expression of IL-10 mRNA of synoviocytes was determined using RT-PCR. There were significant secondary inflammatory reactions in AA rats, which accompanied with the decrease of body and immune organs weight simultaneously. The administration of FR167653 (4, 12, 36 mg/kg, subcutaneously (s.c.)) inhibited the inflammatory response and restored the weight of body and immune organs of AA rats. Synoviocytes proliferation of AA rats significantly increased, and the levels of TNF-alpha and IL-1 in supernatants of synoviocytes in AA rats were also elevated compared with the sham group. The administration of FR167653 (4, 12, 36 mg/kg, s.c.) reduced the above changes significantly. In contrast to TNF-alpha and IL-1, IL-10 production and the level of its mRNA of synoviocytes in AA rats were apparently decreased. FR167653 (4, 12, 36 mg/kg, s.c.) markedly increased IL-10 in synoviocytes at protein and transcription level. The results indicated that FR167653 had a beneficial effect on rats AA due to modulating inflammatory cytokines production of synoviocytes, which played a crucial role in pathogenesis of this disease.

Arginine-rich anti-vascular endothelial growth factor (anti-VEGF) hexapeptide inhibits collagen-induced arthritis and VEGF-stimulated productions of TNF-alpha and IL-6 by human monocytes

Vascular endothelial growth factor (VEGF) has been suggested to play a critical role in the pathogenesis of rheumatoid arthritis (RA). We previously identified a novel RRKRRR hexapeptide that blocked the interaction between VEGF and its receptor through the screening of peptide libraries. In this study, we investigated whether anti-VEGF peptide RRKRRR (dRK6) could suppress collagen-induced arthritis (CIA) and regulate the activation of mononuclear cells of RA patients. A s.c. injection of dRK6 resulted in a dose-dependent decrease in the severity and incidence of CIA and suppressed synovial infiltration of inflammatory cells in DBA/1 mice. In these mice, the T cell responses to type II collagen (CII) in lymph node cells and circulating IgG Abs to CII were also dose-dependently inhibited by the peptides. In addition, VEGF directly increased the production of TNF-alpha and IL-6 from human PBMC. Synovial fluid mononuclear cells of RA patients showed a greater response to VEGF stimulation than the PBMC of healthy controls. The major cell types responding to VEGF were monocytes. Moreover, anti-VEGF dRK6 inhibited the VEGF-induced production of TNF-alpha and IL-6 from synovial fluid mononuclear cells of RA patients and decreased serum IL-6 levels in CIA mice. In summary, we observed first that dRK6 suppressed the ongoing paw inflammation in mice and blocked the VEGF-induced production of proinflammatory cytokines. These data suggest that dRK6 may be an effective strategy in the treatment of RA, and could be applied to modulate various chronic VEGF-dependent inflammatory diseases.

Treatment of experimental arthritis with M2000, a novel designed non-steroidal anti-inflammatory drug

The current study was planned to explore the therapeutic potency of M2000 (beta-D-mannuronic acid), a novel designed non-steroidal anti-inflammatory drug (NSAID) in adjuvant-induced arthritis model. Arthritis was induced in Lewis rats by a single intradermal injection (0.1 ml) of heat-killed Mycobacterium tuberculosis (0.3 mg) in Freund's incomplete adjuvant into the right footpad. Fourteen days after injection of adjuvant, the contralateral left footpad volume was measured. The animals with paw volumes 0.37 ml greater than normal paws were then randomized into treatment groups. Orally and intraperitoneally administrations of test drugs (M2000, 40/mg/kg/day and indomethacin, 2/mg/kg/day) were started on day 15 post-adjuvant injection and continued until final assessment on day 25. The left hind limb was removed for histological evaluation. The WEHI-164 cell line was used for assaying tolerability and matrix metalloproteinase type 2 (MMP-2) activity. MMP-2 activity was assessed using zymography. Pharmacotoxicology study was carried out on animal models based on the evaluation of serum and urine determinants, histology of kidney, gastrointestinal tolerability and body temperature. Results showed that the orally administration as well as intraperitoneally injection of M2000 to arthritic rats induced a significant reduction in paw oedema. Histopathological assessment showed a reduced inflammatory cells infiltrate in joints of treated rats, as well as the number of osteoclasts present in the subchondral bone, tissue oedema and bone erosion in the paws were markedly reduced following M2000 therapy. Cytotoxicity analysis of M2000 showed a much higher tolerability compared with other tested drugs (diclofenac, piroxicam and dexamethasone). The inhibitory effect of M2000 in MMP-2 activity was significantly greater than that of dexamethasone and of piroxicam at a concentration of 200 microg/ml. Moreover, the toxicological study revealed that M2000 had no influence on serum (blood urea nitrogen, creatinine, triglyceride and cholesterol) and urine (urea and urinary protein excretion) determinants, glomerular histology and body temperature in normothermic rats and had no ulcerogenic effects on rats' stomach. Our data show that M2000, as a novel NSAID, could be strongly suggested as the safest anti-inflammatory drug for long-term administration.

Tolerability and anti-inflammatory effects of glucuronoxylomannan in collagen-induced arthritis

This investigation was planned to assess the therapeutic efficacy of glucuronoxylomannan (GXM) in collagen-induced arthritis (CIA). GXM was isolated from culture filtrate of Cryptococcus neoformans var. gattii, serotype C. CIA was induced by the immunization of Dark Agouti rats with bovine type II collagen in incomplete Freund's adjuvant. GXM solution at two doses, 25 and 50 mg/kg, was administered intraperitoneally. Onset of i.p. injections of GXM to prevention and treatment groups was days 0 and 10 postimmunization, respectively. The WEHI-164 cell line was used for assaying tolerability, matrix metalloproteinase type 2 (MMP-2) activity and apoptosis. MMP-2 activity was assessed using zymography. For assessment of apoptosis, the terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labelling method was used. The results of this experiment showed that the treatment of CIA with GXM at a dose of 50 mg/kg could suppress disease development both prophylactically and therapeutically. This beneficial effect of GXM was associated with a significant decrease in the anti-CII antibody response compared with untreated rats. Moreover, GXM therapy could diminish MMP-2 activity, but it had no notable effect on apoptosis. GXM also showed a high tolerability compared with certain steroidal and non-steroidal anti-inflammatory drugs. We conclude that GXM suppresses the development of disease in CIA and it could be recommended as a new immunosuppressive and anti-inflammatory agent for further investigations.

Polymorphism of immunomodulatory cytokine genes: implications in acute renal failure

Experimental studies have incriminated cytokines and other immunoregulatory molecules as important mediators of tissue injury in acute renal failure (ARF). The relative importance of genetic factors, e.g. polymorphisms involving cytokine genes, in influencing susceptibility to and severity of ARF is unknown. This review summarizes the existing experimental and clinical studies supporting the role of inflammation in ARF, and critically examines human studies that have examined polymorphism of two critical cytokine genes, tumor necrosis factor-alpha and interleukin-10, as potential determinants of susceptibility to and severity of acute infectious and inflammatory diseases. Conclusions are drawn on the application of genetic epidemiology to the field of ARF and the rationale for further research on the role of genetic markers in ARF.

T-cell-activation inhibitors in rheumatoid arthritis

As rheumatoid arthritis (RA) is a chronic inflammatory disabling disease and a cure is not available, optimisation of therapeutic strategies is mandatory. Within recent years many new details of the inflammatory cascade(s) have been elaborated, leading to new therapeutic options such as neutralisation of tumour necrosis factor-alpha (TNFalpha). T-cell inhibition is another new approach to the treatment of RA. However, it is important to note two points: first, the role of T lymphocytes in the initiation and/or perpetuation of RA is still debated controversially. Second, there are few truly T-cell-specific agents that have proven to be effective and are established in the treatment of inflammatory disorders. Leflunomide may be considered one such agent; another in development is the fusion protein CTLA4-Ig. From a clinical perspective, studies demonstrating efficacy of these agents might represent the strongest support for a role of T cells in RA. In addition to leflunomide and CTLA4-Ig, therapeutic agents with activity against T cells, including anti-CD4 antibodies, cyclosporin, tacrolimus and T-cell receptor (TCR)-Vbeta-chain vaccination strategies, have been studied in patients with RA. Combination therapies including any of these T-cell-activation inhibitors with non-T-cell-specific agents such as methotrexate, antimalarials or anti-TNFalpha biologicals may prove the most effective strategies in controlling this complex disease.

Feline Immunodeficiency Virus Vectors for Efficient Transduction of Primary Human Synoviocytes: Application to an Original Model of Rheumatoid Arthritis

The potential of gene therapeutics is hindered by the limitations of the delivery systems presently available. Recently, human immunodeficiency virus (HIV) vectors have been developed that allow the efficient and stable transduction of primary nondividing cells in vivo. Because of the safety concerns raised by HIV vectors, we developed a gene delivery system derived from the ungulate lentivirus feline immunodeficiency virus (FIV). We describe in the present study the optimization of the safety and efficiency of this system that proved to be as potent as HIV vectors to transduce nondividing cells, with titers over 10(8) transducing units per ml. We used this tool to transduce TNF-alpha into human primary synoviocytes, and showed a high efficiency of transduction. TNF-alpha-transduced synoviocytes injected into the knee joints of severe combined immunodeficient (SCID) mice induced cell proliferation, as well as cartilage and bone erosion as soon as day 7, creating a standardized, humanized animal model relevant for rheumatoid arthritis. FIV vectors appear to be promising tools for biologic research and gene therapy.

Effector function of type II collagen-stimulated T cells from rheumatoid arthritis patients: Cross-talk between T cells and synovial fibroblasts

OBJECTIVE

To investigate the effector function exerted by type II collagen (CII)-stimulated T cells on rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS), and to determine their contribution to RA pathogenesis.

METHODS

We used enzyme-linked immunosorbent assays to measure the levels of interleukin-15 (IL-15), tumor necrosis factor alpha (TNFalpha), and IL-18 production by FLS that were cocultured with antigen-activated T cells. Likewise, we analyzed the levels of interferon-gamma (IFN gamma) and IL-17 production by RA T cells coincubated with FLS. To investigate the cross-talk between CII-stimulated T cells and RA FLS, we examined the effect of using a transwell membrane to separate T cells and FLS in a culture chamber, as well as the effect of adding an antibody to block CD40 ligation.

RESULTS

The levels of IL-15, TNF alpha, IFN gamma, and IL-17 were all significantly increased in the serum of RA patients compared with normal control serum. Among the patients, the group with a stronger T cell proliferation response to CII showed higher levels of these inflammatory mediators. When coincubated with RA FLS, these T cells induced the production of IL-15, TNF alpha, and IL-18 by FLS with an intensity that increased in proportion to the duration of CII stimulation. T cells, in turn, responded to FLS stimulation by secreting higher amounts of IL-17 and IFN gamma in coculture. Interestingly, T cells that were activated by CII for longer periods of time showed stronger induction of these cytokines. The cross-talk between T cells and FLS appeared to require direct cell-cell contact as well as CD40 ligation, at least in part.

CONCLUSION

Through repeated stimulation by CII, RA synovial T cells became trained effector cells that induced the production of proinflammatory mediators by FLS, while in the process the T cells becoming more sensitized to the activation signal from FLS.

Evaluation of p53, bcl-2, and interleukin-15 levels in gingival crevicular fluid of cyclosporin A-treated patients

BACKGROUND

Apoptosis plays an important role in the maintenance of tissue homeostasis. Considering that apoptosis mediators may play a role in the pathogenesis of drug-induced gingival overgrowth, this study was conducted to evaluate p53, bcl-2, and interleukin-15 (IL-15) levels in gingival crevicular fluid (GCF) of cyclosporin A (CsA)-treated patients.

METHODS

Twenty renal transplant patients exhibiting CsA-induced gingival overgrowth and 15 systemically healthy gingivitis patients were included in the study; 15 systemically and periodontally healthy volunteer subjects served as the healthy control group. GCF samples were obtained from one interdental site with gingival overgrowth (GO+) and one site without (GO-) from each CsA-treated patient; hyperplasia index, probing depth, papilla bleeding index, and plaque presence were recorded. One site from each gingivitis patient and healthy control was selected, GCF samples were obtained, and the same clinical parameters were recorded. GCF p53, bcl-2, and IL-15 levels were analyzed by enzyme-linked immunosorbent assay. The results were tested statistically.

RESULTS

p53 and bcl-2 levels were below the minimum detectable level in all GCF samples analyzed. CsA GO+ and CsA GO- sites, as well as gingivitis sites, exhibited significantly higher GCF levels of IL-15 compared to healthy controls (P<0.05). The difference between CsA GO+ sites and gingivitis sites was not statistically significant, although the total amount of IL-15 in CsA GO+ sites was lower than gingivitis sites (P>0.05). The total amount of IL-15 in CsA GO- sites was significantly lower than gingivitis sites (P<0.05). No significant correlation was found between the clinical parameters and GCF IL-15 levels (P>0.05).

CONCLUSIONS

The pathogenesis of CsA-induced gingival overgrowth is multifactorial. The findings of the present study indicate that IL-15 may play a role in the pathogenesis of CsA-induced gingival overgrowth due to its interactions with CsA and its role in apoptosis and inflammation.