Celastrus aculeatus Merr. suppresses the induction and progression of autoimmune arthritis by modulating immune response to heat-shock protein 65

Complementary and alternative medicine products are increasingly being used for the treatment of autoimmune diseases. However, the mechanisms of action of these agents are not fully defined. Using the rat adjuvant arthritis (AA) model of human rheumatoid arthritis, we determined whether the ethanol extract of Celastrus aculeatus Merr. (Celastrus), a Chinese herb, can down-modulate the severity of AA, and also examined the Celastrus-induced changes in immune responses to the disease-related antigen mycobacterial heat-shock protein 65 (Bhsp65). AA was induced in the Lewis (LEW; RT.1l) rat by immunization subcutaneously with heat-killed M. tuberculosis H37Ra (Mtb). Celastrus was fed to LEW rats by gavage daily, beginning either before Mtb challenge (preventive regimen) or after the onset of AA (therapeutic regimen). An additional group of rats was given methotrexate for comparison. All rats were graded regularly for the signs of arthritis. In parallel, the draining lymph node cells of Celastrus-treated rats were tested for proliferative and cytokine responses, whereas their sera were tested for the inflammatory mediator nitric oxide. Celastrus feeding suppressed both the induction as well as the progression of AA, and the latter effect was comparable to that of methotrexate. Celastrus treatment induced relative deviation of the cytokine response to anti-inflammatory type and enhanced the production of anti-Bhsp65 antibodies, which are known to be protective against AA. Celastrus feeding also reduced the levels of nitric oxide. On the basis of our results, we suggest further systematic exploration of Celastrus as an adjunct therapeutic modality for rheumatoid arthritis

The determinants of susceptibility/resistance to adjuvant arthritis in rats

Adjuvant arthritis (AA) serves as an excellent model for human rheumatoid arthritis. AA is readily inducible in certain rat strains, but not in others. Susceptibility/resistance to AA is determined by multiple factors. Among the genetic factors, both MHC and non-MHC genes contribute to arthritis susceptibility, and specific quantitative trait loci show association with the severity of the disease. Differential T-cell proliferative and cytokine responses, as well as antibody responses, to heat-shock proteins are evident when comparing AA-susceptible and AA-resistant rats. In addition, neuroendocrine factors and the housing environment can further modulate arthritis susceptibility/severity in particular rat strains

Immunomodulation of Autoimmune Arthritis by Herbal CAM

Rheumatoid arthritis (RA) is a debilitating autoimmune disease of global prevalence. The disease is characterized by synovial inflammation leading to cartilage and bone damage. Most of the conventional drugs used for the treatment of RA have severe adverse reactions and are quite expensive. Over the years, increasing proportion of patients with RA and other immune disorders are resorting to complementary and alternative medicine (CAM) for their health needs. Natural plant products comprise one of the most popular CAM for inflammatory and immune disorders. These herbal CAM belong to diverse traditional systems of medicine, including traditional Chinese medicine, Kampo, and Ayurvedic medicine. In this paper, we have outlined the major immunological pathways involved in the induction and regulation of autoimmune arthritis and described various herbal CAM that can effectively modulate these immune pathways. Most of the information about the mechanisms of action of herbal products in the experimental models of RA is relevant to arthritis patients as well. The study of immunological pathways coupled with the emerging application of genomics and proteomics in CAM research is likely to provide novel insights into the mechanisms of action of different CAM modalities

Mediators of Inflammation-Induced Bone Damage in Arthritis and Their Control by Herbal Products

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the synovial joints leading to bone and cartilage damage. Untreated inflammatory arthritis can result in severe deformities and disability. The use of anti-inflammatory agents and biologics has been the mainstay of treatment of RA. However, the prolonged use of such agents may lead to severe adverse reactions. In addition, many of these drugs are quite expensive. These limitations have necessitated the search for newer therapeutic agents for RA. Natural plant products offer a promising resource for potential antiarthritic agents. We describe here the cellular and soluble mediators of inflammation-induced bone damage (osteoimmunology) in arthritis. We also elaborate upon various herbal products that possess antiarthritic activity, particularly mentioning the specific target molecules. As the use of natural product supplements by RA patients is increasing, this paper presents timely and useful information about the mechanism of action of promising herbal products that can inhibit the progression of inflammation and bone damage in the course of arthritis

Modified Huo-Luo-Xiao-Ling Dan Suppresses Adjuvant Arthritis by Inhibiting Chemokines and Matrix-Degrading Enzymes

Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting the joints that can lead to deformities and disability. The prolonged use of conventionally used drugs is associated with severe adverse reactions. Therefore, safer and less expensive therapeutic products are continually being sought. Huo-Luo-Xiao-Ling dan (HLXL), a traditional Chinese herbal mixture, and its modified versions possess anti-arthritic activity. In this paper, we examined the influence of modified HLXL on two of the key mediators of arthritic inflammation and tissue damage, namely, chemokines and matrix-metalloproteinases (MMPs) in the rat adjuvant-induced arthritis (AA) model of RA. We treated arthritic Lewis rats with HLXL (2.3 g/kg) by daily gavage beginning at the onset of AA. The control rats received the vehicle. At the peak phase of AA, rats were sacrificed and their draining lymph node cells (LNC) and spleen adherent cells (SAC) were tested. The HLXL-treated rats showed a significant reduction in the levels of chemokines (RANTES, MCP-1, MIP-1α, and GRO/KC), MMPs (MMP 2 and 9), as well as cytokines (IL-6 and IL-17) that induce them, compared to the control vehicle-treated rats. Thus, HLXL controls arthritis in part by suppressing the mediators of immune pathology, and it might offer a promising alternative/adjunct treatment for RA

Suppression of Ongoing Experimental Arthritis by a Chinese Herbal Formula (Huo-Luo-Xiao-Ling Dan) Involves Changes in Antigen-Induced Immunological and Biochemical Mediators of Inflammation

Rheumatoid arthritis (RA) is one of the major autoimmune diseases of global prevalence. The use of the anti-inflammatory drugs for the treatment of RA is associated with severe adverse reactions and toxicity. This limitation has necessitated the search for novel therapeutic products. We report here a traditional Chinese medicine-based herbal formula, Huo luo xiao ling dan (HLXL), which has potent antiarthritic activity as validated in the rat adjuvant-induced arthritis (AA) model. HLXL (2.3 g/Kg) was fed to Lewis (RT.11) rats daily by gavage beginning at the onset of arthritis and then continued through the observation period. HLXL inhibited the severity of ongoing AA. This suppression of arthritis was associated with significant alterations in the T cell proliferative and cytokine responses as well as the antibody response against the disease-related antigen, mycobacterial heat-shock protein 65 (Bhsp65). There was a reduction in the level of the proinflammatory cytokines IL-17 and IL-1β but enhancement of the anti-inflammatory cytokine IL-10 level. In addition, there was inhibition of both the anti-Bhsp65 antibody response and the serum level of nitric oxide. Thus, HLXL is a promising CAM modality for further testing in RA patients

Diversification of T Cell Responses to Carboxy-terminal Determinants within the 65-kD Heat-shock Protein Is Involved in Regulation of Autoimmune Arthritis

The T cell response to the 65-kD mycobacterial heat-shock protein (Bhsp65) has been implicated in the pathogenesis of autoimmune arthritis. Adjuvant arthritis (AA) induced in the Lewis rat (RT-1l) by injection of Mycobacterium tuberculosis serves as an experimental model for human rheumatoid arthritis (RA). However, the immunological basis of regulation of acute AA, or of susceptibility/resistance to AA is not known. We have defined the specificity of the proliferative T cell responses to Bhsp65 during the course of AA in the Lewis rat. During the early phase of the disease (6–9 d after onset of AA), Lewis rats raised T cell responses to many determinants within Bhsp65, spread throughout the molecule. Importantly, in the late phase of the disease (8–10 wk after onset of AA), there was evidence for diversification of the T cell responses toward Bhsp65 carboxy-terminal determinants (BCTD) (namely, 417–431, 441–455, 465–479, 513–527, and 521–535). Moreover, arthritic rats in the late phase of AA also raised vigorous T cell responses to those carboxy-terminal determinants within self(rat) hsp65 (Rhsp65) that correspond in position to the above BCTD. These results suggest that the observed diversification is possibly triggered in vivo by induction of self(Rhsp65)-reactive T cells. Interestingly, another strain of rat, the Wistar Kyoto (WKY/NHsd) rat (RT-1l), with the same major histocompatibility complex class II molecules as the Lewis rat, was found to be resistant to AA. In WKY rats, vigorous responses to the BCTD, to which the Lewis rat responded only in the late phase of AA, were observed very early, 10 d after injection of M. tuberculosis. Strikingly, pretreatment with the peptides comprising the set of BCTD, but not its amino-terminal determinants, provided significant protection to naive Lewis rats from subsequent induction of AA. Thus, T cell responses to the BCTD are involved in regulating inflammatory arthritis in the Lewis rat and in conferring resistance to AA in the WKY rat. These results have important implications in understanding the pathogenesis of RA and in devising new immunotherapeutic strategies for this disease