Effects of Tripterygium wilfordii hook F extracts on induction of cyclooxygenase 2 activity and prostaglandin E2 production

Tripterygium hypoglaucum (Lévl.) Hutch and Its Main Bioactive Components: Recent Advances in Pharmacological Activity, Pharmacokinetics and Potential Toxicity

Tripterygium hypoglaucum (Lévl.) Hutch (THH) is believed to play an important role in health care and disease treatment according to traditional Chinese medicine. Moreover, it is also the representative of medicine with both significant efficacy and potential toxicity. This characteristic causes THH hard for embracing and fearing. In order to verify its prospect for clinic, a wide variety of studies were carried out in the most recent years. However, there has not been any review about THH yet. Therefore, this review summarized its characteristic of components, pharmacological effect, pharmacokinetics and toxicity to comprehensively shed light on the potential clinical application. More than 120 secondary metabolites including terpenoids, alkaloids, glycosides, sugars, organic acids, oleanolic acid, polysaccharides and other components were found in THH based on phytochemical research. All these components might be the pharmacological bases for immunosuppression, anti-inflammatory and anti-tumour effect. In addition, recent studies found that THH and its bioactive compounds also demonstrated remarkable effect on obesity, insulin resistance, fertility and infection of virus. The main mechanism seemed to be closely related to regulation the balance of immune, inflammation, apoptosis and so on in various disease. Furthermore, the study of pharmacokinetics revealed quick elimination of the main component triptolide. The feature of celastrol was also investigated by several models. Finally, the side effect of THH was thought to be the key for its limitation in clinical application. A series of reports indicated that multiple organs or systems including liver, kidney and genital system were involved in the toxicity. Its potential serious problem in liver was paid specific attention in recent years. In summary, considering the significant effect and potential toxicity of THH as well as its components, the combined medication to inhibit the toxicity, maintain effect might be a promising method for clinical conversion. Modern advanced technology such as structure optimization might be another way to reach the efficacy and safety. Thus, THH is still a crucial plant which remains for further investigation.

Beneficial Modulation of Lipid Mediator Biosynthesis in Innate Immune Cells by Antirheumatic Tripterygium wilfordii Glycosides

Tripterygium wilfordii glycosides (TWG) is a traditional Chinese medicine with effectiveness against rheumatoid arthritis (RA), supported by numerous clinical trials. Lipid mediators (LM) are biomolecules produced from polyunsaturated fatty acids mainly by cyclooxygenases (COX) and lipoxygenases (LOX) in complex networks which regulate inflammation and immune responses and are strongly linked to RA. The mechanism by which TWG affects LM networks in RA treatment remains elusive. Employing LM metabololipidomics using ultra-performance liquid chromatography-tandem mass spectrometry revealed striking modulation of LM pathways by TWG in human monocyte-derived macrophage (MDM) phenotypes. In inflammatory M1-MDM, TWG (30 µg/mL) potently suppressed agonist-induced formation of 5-LOX products which was confirmed in human PMNL and traced back to direct inhibition of 5-LOX (IC₅₀ = 2.9 µg/mL). TWG also efficiently blocked thromboxane formation in M1-MDM without inhibiting other prostanoids and COX enzymes. Importantly, in anti-inflammatory M2-MDM, TWG (30 µg/mL) induced pronounced formation of specialized pro-resolving mediators (SPM) and related 12/15-LOX-derived SPM precursors, without COX and 5-LOX activation. During MDM polarization, TWG (1 µg/mL) decreased the capacity to generate pro-inflammatory 5-LOX and COX products, cytokines and markers for M1 phenotypes. Together, suppression of pro-inflammatory LM but SPM induction may contribute to the antirheumatic properties of TWG.

Research Progress of Therapeutic Enzymes and Their Derivatives: Based on Herbal Medicinal Products in Rheumatoid Arthritis

Rheumatoid arthritis (RA) acts as one of the most common, agnogenic and chronic inflammatory-autoimmune disorder which is characterized by persistent synovitis, cartilage destruction, and joint deformities, leads to a wide range of disabilities, and increased mortality, thus imposing enormous burdens. Several drugs with anti-inflammatory and immunomodulatory properties such as celecoxib, diclofenac and methotrexate are being selected as conventional drugs in the allopathic system of medicine for the treatment of RA in clinic. However, there are some serious side effects more or less when using these drugs because of their short poor bioavailability and biological half-life for a long time. These shortcomings greatly promote the exploration and application of new low- or no-toxicity drugs for treating the RA. Meanwhile, a growing number of studies demonstrate that several herbs present certain anti-inflammatory and anti-arthritic activities through different enzymes and their derivatives, which indicate that they are promising therapeutic strategies when targeting these mediators based on herbal medicinal products in RA research. This review article summarizes the roles of the main enzymes and their derivatives during the pathogenesis of RA, and clearly clarifies the explicit and potential targeted actions of herbal medicinal products that have anti-RA activity. Our review provides timely and critical reference for the scientific rationale use of herbal medicinal products, with the increasing basic research and clinical application of herbal medicinal products by patients with RA.

Therapeutic Potential of Triptolide as an Anti-Inflammatory Agent in Dextran Sulfate Sodium-Induced Murine Experimental Colitis

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn’s disease (CD), is a group of chronic and incurable inflammatory diseases involving the gastrointestinal tract. In this study, we investigated the anti-inflammatory effects of triptolide in a dextran sulfate sodium (DSS)-induced mouse colitis model and LPS-activated macrophages and explored the specific molecular mechanism(s). In mice, triptolide treatment showed significant relief and protection against colitis, and it markedly reduced the inflammatory responses of human monocytes and mouse macrophages. Pharmacological analysis and weighted gene co-expression network analysis (WGCNA) suggested that PDE4B may be an important potential targeting molecule for IBD. Exploration of the specific mechanism of action indicated that triptolide reduced the production of ROS, inhibited macrophage infiltration and M1-type polarization by activating the NRF2/HO-1 signaling pathway, and inhibited the PDE4B/AKT/NF-κB signaling cascade, which may help weaken the intestinal inflammatory response. Our findings laid a theoretical foundation for triptolide as a treatment for IBD and revealed PDE4B as a target molecule, thus providing new ideas for the treatment of IBD.

Natural Products for the Treatment of Autoimmune Arthritis: Their Mechanisms of Action, Targeted Delivery, and Interplay with the Host Microbiome

Rheumatoid arthritis (RA) is a chronic, debilitating illness characterized by painful swelling of the joints, inflammation of the synovial lining of the joints, and damage to cartilage and bone. Several anti-inflammatory and disease-modifying drugs are available for RA therapy. However, the prolonged use of these drugs is associated with severe side effects. Furthermore, these drugs are effective only in a proportion of RA patients. Hence, there is a need to search for new therapeutic agents that are effective yet safe. Interestingly, a variety of herbs and other natural products offer a vast resource for such anti-arthritic agents. We discuss here the basic features of RA pathogenesis; the commonly used animal models of RA; the mainstream drugs used for RA; the use of well-characterized natural products possessing anti-arthritic activity; the application of nanoparticles for efficient delivery of such products; and the interplay between dietary products and the host microbiome for maintenance of health and disease induction. We believe that with several advances in the past decade in the characterization and functional studies of natural products, the stage is set for widespread clinical testing and/or use of these products for the treatment of RA and other diseases.

Small Peptides Compound Isolated from Agkistrodon with Antiarthritic Effect in Collagen-Induced Arthritis Rats

Agkistrodon in Chinese medicine has long been used as an effective treatment against rheumatoid arthritis (RA). The present research further investigated the effects of peptides extracted from the crude Agkistrodon on the RA rat model. Extracted peptides were separated by parameter-optimized ion-exchange chromatography (IEC), peptide fractions were further analysed by MALDI-TOF/TOF MS, and nano-LC-MS/MS acquired mass spectra were further characterized using Mascot software, which ranks the best matches in the NCBI database. RT-PCR results in RAW264.7 cells indicated that Agkistrodon peptide components had inhibitory effects against inflammatory cytokines. The therapeutic efficacy of Agkistrodon peptides was evaluated on the Wistar rats with collagen-induced arthritis. Symptom relief and reduced cartilage destruction and bone erosion were observed, which can be explained by the direct suppression of inflammatory cytokines in the joints. Agkistrodon peptides downregulate the expression of TNF-α, IL-1β, and IL-6, which may alleviate cartilage destruction and bone erosion, thus relieving symptoms of RA.

Inhibitory effect of Triperygium wilfordii polyglucoside on dipeptidyl peptidase I in vivo and in vitro

BACKGROUD

Dipeptidyl peptidase I (DPPI), a lysosomal cysteine protease is derived from granule immune cells including mast cell, neutrophils, and toxicity T cells. DPPI can activate serine proteases by removal of dipeptides from N-termini of the pro-proteases, resulting in granule immune cells activation which involved in physiological or pathological responses. Triperygium Wilfordii Polyglucoside (TWP) is one of the traditional Chinese medicines, and commonly used in rheumatoid arthritis (RA) treatment. The present study intended to evaluate the effects of TWP on DPPI activity.

METHODS

In vivo and in vitro studies were carried out to investigate the functions of TWP or triptolide (TP) on DPPI activities in serum, tissues of CIA rats. Rats were divided into five groups randomly: normal group, untreated CIA rat group, TWP treatment CIA groups (the low dose 2.5mg/100g body-weight and high dose 5mg/100g body-weight), and TP treatment CIA group (4μg/100g body-weight). Arthritis development was monitored visually, and joint pathology was examined radiologically. Total protein concentrations in synovial fluids (SFs) were determined by BCA method. Serums and tissue homogenates from CIA rats were collected and DPPI activities were detected using fluorescence substrate GF-AFC. The in vitro interactions between DPPI in serums or in tissue homogenates and TWP or TP were assessed.

RESULTS

TWP-treated CIA rats showed a significant improvement in bone erosion. TWP significantly suppressed paw swelling and total protein concentration in the SFs of CIA rats compared with untreated CIA rats. The elevated activities of DPPI in serums or tissues of CIA rats were significantly inhibited by TWP, but not by TP in vivo. The inhibitory effects of TWP on DPPI activities were also confirm by in vitro study.

CONCLUSION

One of the therapeutic functions of TWP in RA treatment could be inhibiting DPPI activity in serums and synovial tissue produced during RA development, and then reducing inflammatory serine proteases activities and further recovering CIA rats from RA symptoms.

Drug-Herb Interactions in the Elderly Patient with IBD: a Growing Concern

OPINION STATEMENT

Inflammatory bowel disease (IBD), which includes conditions such as Crohn's disease and ulcerative colitis, is becoming more prevalent with the elderly being the fastest growing group. Parallel to this, there is an increasing interest in the use of complementary and alternative medicine (CAM). Nearly half of patients with IBD have used CAM at one time. The elderly patients, however, are burdened by comorbid conditions, polypharmacy, and altered functional status. With increasing use of complementary and alternative medicine in our elderly patients with IBD, it is vital for the provider to provide counsel on drug-herb potential interactions. CAM includes herbal products, diet, dietary supplements, acupuncture, and prayer. In this paper, we will review common CAM, specifically herbs, that are used in patients with IBD including the herb background, suggested use, evidence in IBD, and most importantly, potential interactions with IBD medications used in elderly patients. Most important evidence-based adverse events and drug-herb interactions are summarized. The herbs discussed include Triticum aestivum (wheat grass), Andrographis paniculata (chiretta), Boswellia serrata, tormentil, bilberry, curcumin (turmeric), Plantago ovata (blond psyllium), Oenothera biennis (evening primrose oil), germinated barley foodstuff, an herbal preparation of myrrh, chamomile and coffee extract, chios mastic gum, wormwood (absinthe, thujone), Cannabis sativa (marijuana, THC), tripterygium wilfordii (thunder god vine), Ulmus rubra (slippery elm bark), trigonella foenugraecum (fenugreek), Dioscorea mexicana (wild yam), Harpagophytum procumbens (devil's claw), ginger, cinnamon, licorice, and peppermint.

Celastrol: A Spectrum of Treatment Opportunities in Chronic Diseases

The identification of new bioactive compounds derived from medicinal plants with significant therapeutic properties has attracted considerable interest in recent years. Such is the case of the Tripterygium wilfordii (TW), an herb used in Chinese medicine. Clinical trials performed so far using its root extracts have shown impressive therapeutic properties but also revealed substantial gastrointestinal side effects. The most promising bioactive compound obtained from TW is celastrol. During the last decade, an increasing number of studies were published highlighting the medicinal usefulness of celastrol in diverse clinical areas. Here we systematically review the mechanism of action and the therapeutic properties of celastrol in inflammatory diseases, namely, rheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel diseases, osteoarthritis and allergy, as well as in cancer, neurodegenerative disorders and other diseases, such as diabetes, obesity, atherosclerosis, and hearing loss. We will also focus in the toxicological profile and limitations of celastrol formulation, namely, solubility, bioavailability, and dosage issues that still limit its further clinical application and usefulness.

Celastrol inhibits prostaglandin E2-induced proliferation and osteogenic differentiation of fibroblasts isolated from ankylosing spondylitis hip tissues in vitro

BACKGROUND

Heterotopic ossification on the enthesis, which develops after subsequent inflammation, is one of the most distinctive features in ankylosing spondylitis (AS). Prostaglandin E2 (PGE-2) serves as a key mediator of inflammation and bone remodeling in AS. Celastrol, a well-known Chinese medicinal herb isolated from Tripterygium wilfordii, is widely used in treating inflammatory diseases, including AS. It has been proven that it can inhibit lipopolysac-charide-induced expression of various inflammation mediators, such as PGE-2. However, the mechanism by which celastrol inhibits inflammation-induced bone forming in AS is unclear.

OBJECTIVE

To investigate whether celastrol could inhibit isolated AS fibroblast osteogenesis induced by PGE-2.

METHODS

Hip synovial tissues were obtained from six AS patients undergoing total hip replacement in our hospital. Fibroblasts were isolated, primarily cultured, and then treated with PGE-2 for osteogenic induction. Different doses of celastrol and indometacin were added to observe their effects on osteogenic differentiation. Cell proliferation, osteogenic markers, alizarin red staining as well as the activity of alkaline phosphatase were examined in our study.

RESULTS

Celastrol significantly inhibits cell proliferation of isolated AS fibroblasts and in vitro osteogenic differentiation compared with control groups in a time- and dose-dependent manner.

CONCLUSION

Our results demonstrated that celastrol could inhibit isolated AS fibroblast proliferation and in vitro osteogenic differentiation. The interaction of PI3K/AKT signaling and Wnt protein may be involved in the process. Further studies should be performed in vivo and animal models to identify the potential effect of celastrol on the bone metabolism of AS patients.

Potent health effects of pomegranate

Accumulating data clearly claimed that Punica granatum L. (pomegranate) has several health benefits. Pomegranates can help prevent or treat various disease risk factors including high blood pressure, high cholesterol, oxidative stress, hyperglycemia, and inflammatory activities. It is demonstrated that certain components of pomegranate such as polyphenols have potential antioxidant, anti-inflammatory, and anticarcinogenic effects. The antioxidant potential of pomegranate juice is more than that of red wine and green tea, which is induced through ellagitannins and hydrosable tannins. Pomegranate juice can reduce macrophage oxidative stress, free radicals, and lipid peroxidation. Moreover, pomegranate fruit extract prevents cell growth and induces apoptosis, which can lead to its anticarcinogenic effects. In addition, promoter inhibition of some inflammatory markers and their production are blocked via ellagitannins. In this article, we highlight different studies on the therapeutic effects of pomegranate and their suggested mechanisms of actions.

Extracts of Tripterygium wilfordii Hook F in the Treatment of Rheumatoid Arthritis: A Systemic Review and Meta-Analysis of Randomised Controlled Trials

Clinical trials have reported the effects of Tripterygium wilfordii Hook F (TwHF) extracts (TEs) in the treatment of rheumatoid arthritis (RA); however, the results have been inconsistent. This meta-analysis is aimed to assess the safety of TEs and their effects on the treatment of RA. Randomised controlled trials (RCTs) comparing the effects of TEs and placebo (PBO) or disease-modifying antirheumatic drugs (DMARDs) in patients with RA were included. Weighted mean differences (MDs) were calculated for net changes by employing fixed-effect or random-effects models. After filtering, ten RCTs (involving 733 participants) were included in this study. The methodological quality of these studies was generally low. Compared with DMARDs, TEs alone produced a mild increase in grip strength (GS) (P = 0.02; standard mean difference (SMD) = 0.81; 95% confidence interval (CI): 0.14 to 1.48). The most common adverse effects (AEs) of TEs were gastrointestinal discomfort, menstruation disorders, and amenorrhea. In conclusion, TEs, as a sort of “herbal DMARD,” could be as effective as synthetic DMARDs in the treatment of RA. However, the efficacy of TEs in treating RA should be further estimated with better designed, fully powered, confirmatory RCTs that apply the American College of Rheumatology (ACR) improvement criteria to evaluate their outcomes.

Tripterygium wilfordii Hook F (a traditional Chinese medicine) for primary nephrotic syndrome

BACKGROUND

Tripterygium wilfordii Hook F (TwHF), a traditional Chinese herbal medicine used as an immunosuppressive agent, has been prescribed in China for patients with primary nephrotic syndrome (NS) for more than two decades. Although patients with primary NS in China have benefited from TwHF treatment, its properties have not yet been fully understood.

OBJECTIVES

To assess the benefits and harms of TwHF for patients with primary NS.

SEARCH METHODS

We searched the Cochrane Renal Group's specialised register (August 2012), Cochrane Register of Controlled Trials (CENTRAL, The Cochrane Library 2012, Issue 8), EMBASE (1966 to August 2012), and MEDLINE (1966 to August 2012). We also searched CBM (Chinese Biological Medical Database) (1978 to November 2010), CNKI (Chinese National Knowledge Infrastructure) (1979 to November 2010), VIP (ChongQing WeiPu Chinese Science and Technology Periodical Database) (1989 to November 2010), WanFang Database (1980 to November 2010), and reference lists of articles (6 November 2010).

SELECTION CRITERIA

Only randomised controlled trials (RCTs) were included. Two standardised preparations of TwHF were investigated: ethanol-ethyl acetate extract and chloroform-methanol extract. All other TwHF preparations were excluded because of reported toxicities. Other traditional Chinese herbal medicines were also excluded. All included RCTs had a follow-up of at least three months.

DATA COLLECTION AND ANALYSIS

Data extraction and risk of bias assessment were undertaken independently by two authors. Where details of randomised sequence generation and allocation concealment were absent or inadequately reported, we contacted original study investigators for verification and details of the procedure. For dichotomous outcomes (remission and drug-related adverse events) we used risk ratio (RR) with 95% confidence intervals (95% CI) and mean difference (MD) for continuous outcomes (urinary protein excretion, serum albumin and serum creatinine).

MAIN RESULTS

Ten studies enrolling 630 participants were included. Overall, the quality of evidence was suboptimal due to the small number of included studies enrolling small numbers of participants; short follow-up in each study; only a few studies in each comparison category; and major concerns with methodological bias. Four studies (293 participants) contributed to the comparison of TwHF versus non-TwHF. TwHF significantly increased complete remission (RR 1.46, 95% CI 1.18 to 1.80) and complete or partial remission (RR 1.26, 95% CI 1.10 to 1.44) without escalating the adverse events profile at the last follow-up (12 to 16 months). Four studies (223 participants) compared TwHF with prednisone. There were no statistically significant differences between complete remission, partial remission, and complete or partial remission. Two studies (114 participants) contributed to the comparison of TwHF versus cyclophosphamide (CPA) at the last follow-up (3 to 12 months). There were no statistically significant differences between complete, partial, or complete or partial remission. One study (46 participants) reported TwHF was associated with a significantly lower serum creatinine compared with CPA (MD -14.00 μmol/L, 95% CI -26.43 to -1.57). No serious adverse events of TwHF were observed. One study (37 participants) reported TwHF was associated with a significantly lower risk of psychosis when compared to prednisone (RR 0.11, 95% CI 0.01 to 0.75), and two studies showed a significantly lower risk of hair loss with TwHF when compared to CPA ((2 studies, 114 participants): RR 0.11, 95% CI 0.02 to 0.59).

AUTHORS' CONCLUSIONS

TwHF may have an add-on effect on remission in patients with primary NS. There was insufficient evidence to assess if TwHF was as effective as prednisone or CPA. More methodologically sound and sufficiently powered studies, with adequate follow-up would help to better inform management options for the use of TwHF for primary NS. TwHF should be further directly compared with other widely used immunosuppressive agents after the superiority over placebo or no treatment has been clearly established.

Impairment of triptolide on liver mitochondria in isolated liver mitochondria and HL7702 cell line

OBJECTIVE

To observe the impairing effects of triptolide on liver mitochondria in isolated rat-liver mitochondria and human normal liver HL7702 cell line.

METHODS

Rat-liver mitochondria were isolated from adult female Sprague-Dawley (SD) rats. Liver mitochondria were incubated with 0, 1.25, 2.5, 5 and 10 μmol/L triptolide for detecting mitochondrial swelling and with 0, 2.5, 5 and 10 μmol/L triptolide for mitochondrial permeability transition pore (MPTP) activity. Mitochondrial swelling was estimated by measuring the apparent absorbance change during 600 s in the mitochondrial suspensions at 520 nm with a mitochondrial swelling examining kit. The effect of triptolide on MPTP was determined with a fluorescence detection kit by detecting the fluorescence intensity at an excitation wavelength of 488 nm emitted at 527 nm. Human normal liver HL7702 cells were treated without or with 0.02, 0.1 and 0.5 μmol/L triptolide for 24 h for analyzing mitochondrial transmembrane potential (Δψm) and reactive oxygen species (ROS). Δψm was measured using the fluorescent probe 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1). ROS was measured using fluorescent probe 2',7'-dichlorofluorescin diacetate (DCFH-DA). The cells were harvested and dyed with JC-1 and DCFH-DA, and analyzed by flow cytometry, respectively.

RESULTS

Incubation of isolated mitochondria with triptolide results in swollen mitochondria in a concentration-dependent manner. Moreover, triptolide significantly activated mitochondrial permeability transition at 5 and 10 μmol/L (P<0.05 and P<0.01). When HL7702 cells were exposed to a various concentration triptolide for 24 h, mitochondrial membrane depolarization and increase of ROS were caused by triptolide in a concentration-dependent manner. Triptolide significantly induced the mitochondrial membrane depolarization at 0.1 and 0.5 μmol/L (P<0.05 and P<0.01) and the increase of ROS at 0.1 and 0.5 μmol/L (P<0.05 and P<0.01).

CONCLUSION

Triptolide could induce mitochondrial impairment, which may be one of the mechanisms by which hepatotoxicity occurs.

Triptolide in the treatment of psoriasis and other immune-mediated inflammatory diseases

Apart from cancer chronic (auto)immune-mediated diseases are a major threat for patients and a challenge for physicians. These conditions include classic autoimmune diseases like systemic lupus erythematosus, systemic sclerosis and dermatomyositis and also immune-mediated inflammatory diseases such as rheumatoid arthritis and psoriasis. Traditional therapies for these conditions include unspecific immunosuppressants including steroids and cyclophosphamide, more specific compounds such as ciclosporin or other drugs which are thought to act as immunomodulators (fumarates and intravenous immunoglobulins). With increasing knowledge about the underlying pathomechanisms of the diseases, targeted biologic therapies mainly consisting of anti-cytokine or anti-cytokine receptor agents have been developed. The latter have led to a substantial improvement of the induction of long term remission but drug costs are high and are not affordable in all countries. In China an extract of the herb Tripterygium wilfordii Hook F. (TwHF) is frequently used to treat autoimmune and/or inflammatory diseases due to its favourable cost-benefit ratio. Triptolide has turned out to be the active substance of TwHF extracts and has been shown to exert potent anti-inflammatory and immunosuppressive effects in vitro and in vivo. There is increasing evidence for an immunomodulatory and partly immunosuppressive mechanism of action of triptolide. Thus, compounds such as triptolide or triptolide derivatives may have the potential to be developed as a new class of drugs for these diseases. In this review we summarize the published knowledge regarding clinical use, pharmacokinetics and the possible mode of action of triptolide in the treatment of inflammatory diseases with a particular focus on psoriasis.

Extract of Tripterygium wilfordii Hook F Protect Dopaminergic Neurons Against Lipopolysaccharide-Induced Inflammatory Damage

Activation of microglia is a critical pathological marker of Parkinson's disease. Activated microglia produces proinflammatory and neurotoxic factors, which cause neurons to induce neurodegeneration. Although it is believed that Chinese herbs, such as Tripterygium wilfordii Hook F, can ease inflammatory diseases, little is known about its benefit to neurodegenerative disease, like Parkinson's disease. In this study, we report the extract of Tripterygium wilfordii Hook F with a novel extraction method significantly protected dopaminergic neurons from LPS-induced degeneration in rat mesencephalic neuron-glia cultures. Cells pretreated with the extract have shown dose-dependent inhibition of LPS-induced TNFα and excessive NO production. More importantly, the total number of activated microglia was greatly reduced in these pretreated cells. Our results suggest that the extract of Tripterygium wilfordii Hook F has a strong bioactive function to diminish the pro-inflammatory factors, such as TNFα and NO. These data might also shed light for future neurodegenerative disease therapy.

Suppressive Effects of a Chinese Herbal Medicine Qing-Luo-Yin Extract on the Angiogenesis of Collagen-induced Arthritis in Rats

Qing-Luo-Yin (QLY), a traditional Chinese herbal medicine for the treatment of rheumatoid arthritis, is a combination of the extracts of Sophora flavescens Ait., Phellodendron amurense Rupr., Sinomenium acutum Rehd. et Wils. and Dioscorea hypoglauca Palib. The suppressive effect of QLY on the development of angiogenesis was investigated in a rat model of collagen-induced arthritis (CIA). QLY (0.3 g/kg) was orally administered daily for 27 days. Neo-angiogenesis, pannus and cartilage damage, the expression of metalloproteinases (MMP)-3 messenger RNA (mRNA) and the level of the tissue inhibitor of matrix metalloproteinase (TIMP)-1 in the synovium were examined by histology, in situ hybridization and immunohistochemiscal assays, respectively. It was observed that the articular morphological alterations, the over-expression of MMP-3 mRNA and the reduced production of TIMP-1 in CIA rats were significantly ameliorated by QLY. QLY performed about as effectively as tripterygium glycosidorum tablets (0.1 g/kg) extracted from Tripterygium wilfordii Hook. f.. These results indicate that QLY exerts a suppressive effect on the angiogenesis of CIA rats, and suggest that the therapeutic effect of QLY could be due to restoring the balance of MMP-3 and TIMP-1 in rheumatoid synovium.

Botanical Extracts from Rosehip (Rosa canina), Willow Bark (Salix alba), and Nettle Leaf (Urtica dioica) Suppress IL-1β-Induced NF-κB Activation in Canine Articular Chondrocytes

The aim of this study was to characterize the anti-inflammatory mode of action of botanical extracts from rosehip (Rosa canina), willow bark (Salix alba), and nettle leaf (Urtica dioica) in an in vitro model of primary canine articular chondrocytes. Methods. The biological effects of the botanical extracts were studied in chondrocytes treated with IL-1β for up to 72 h. Expression of collagen type II, cartilage-specific proteoglycan (CSPG), β1-integrin, SOX-9, COX-2, and MMP-9 and MMP-13 was examined by western blotting. Results. The botanical extracts suppressed IL-1β-induced NF-κB activation by inhibition of IκBα phosphorylation, IκBα degradation, p65 phosphorylation, and p65 nuclear translocation. These events correlated with downregulation of NF-κB targets including COX-2 and MMPs. The extracts also reversed the IL-1β-induced downregulation of collagen type II, CSPG, β1-integrin, and cartilage-specific transcription factor SOX-9 protein expression. In high-density cultures botanical extracts stimulated new cartilage formation even in the presence of IL-1β. Conclusions. Botanical extracts exerted anti-inflammatory and anabolic effects on chondrocytes. The observed reduction of IL-1β-induced NF-κB activation suggests that further studies are warranted to demonstrate the effectiveness of plant extracts in the treatment of OA and other conditions in which NF-κB plays pathophysiological roles.

Triptolide enhances the sensitivity of multiple myeloma cells to dexamethasone via microRNAs

Recently triptolide (TPL) has been proved to have the capacity to inhibit the proliferation of multiple myeloma (MM) cells as well as leukemic cells in vitro. In the present study, we found a synergistic effect when TPL was added to dexamethasone to induce apoptosis in MM.1S cells. This combination induced a significantly higher proportion of apoptotic cells compared with those treated with each drug separately. TPL down-regulated the expression of miR142 - 5p and miR181a, which have been shown to inhibit glucocorticoid receptor (GR) expression. MicroRNA mimics and inhibitors inhibited or enhanced the synergistic effect between TPL and dexamethasone in inducing apoptosis in MM.1S cells, suggesting an important role of miR142 - 5p and miR181a in GR regulation by TPL. The in vitro proapoptotic effect of TPL associated with dexamethasone reveals a new lead for further clinical investigation into the treatment of patients with MM with TPL.

Triptolide exhibits anti-inflammatory, anti-catabolic as well as anabolic effects and suppresses TLR expression and MAPK activity in IL-1β treated human intervertebral disc cells

INTRODUCTION

Increased levels of proinflammatory cytokines seem to play a pivotal role in the development of back pain in a subpopulation of patients with degenerative intervertebral disc (IVD) disease. As current treatment options are mostly limited to surgical interventions or conservative treatment, anti-inflammatory substances might offer a novel, more target-orientated therapeutic approach. Triptolide (TPL), a natural substance found in the Chinese medicinal herb Tripterygium wilfordii Hook, has been demonstrated to possess anti-inflammatory effects in various cells, but no studies exist so far for the IVD. Therefore, the aim of this study was to determine the effects of TPL on human IVD cells by analyzing changes in gene expression and underlying molecular mechanisms.

MATERIALS AND METHODS

In order to investigate the anti-inflammatory, anabolic and anti-catabolic effect of TPL, dose-dependency experiments (n = 5) and time course experiments (n = 5) were performed on IL-1β prestimulated human IVD cells and changes in gene expression of IL-6/-8, TNF-α, PGE2S, MMP1/2/3/13, aggrecan and collagen-I/-II were analyzed by real-time RT-PCR. The molecular mechanisms underlying the effects observed upon TPL treatment were investigated by analyzing involvement of Toll-like receptors TLR2/4 (real-time RT-PCR, n = 5), NF-κB, MAP kinases p38, ERK and JNK (immunoblotting and immunocytochemistry, n = 4) as well as RNA polymerase II (immunoblotting, n = 3).

RESULTS

Results showed that 50 nM TPL exhibited an anti-inflammatory, anti-catabolic and anabolic effect on the mRNA level for IL-6/-8, PGE2S, MMP1/2/3/13, aggrecan, collagen-II and TLR2/4, with most pronounced changes after 18 h for proinflammatory cytokines and MMPs or 30 h for TLRs and matrix proteins. However, we also observed an up-regulation of TNF-α at higher concentrations. The effects of TPL did not seem to be mediated via an inhibition of NF-κB or a decrease of RNA polymerase II levels, but TPL influenced activity of MAP kinases p38 and ERK (but not JNK) and expression of TLR2/4.

CONCLUSIONS

In conclusion, TPL may possess promising potential for the treatment of inflammation-related discogenic back pain in vitro, but its analgetic effect will need to be confirmed in an appropriate in vivo animal model.

Using 18F-FDG microPET imaging to measure the inhibitory effects of Clematis chinensis Osbeck on the pro-inflammatory and degradative mediators associated with inflammatory arthritis

AIM OF THE STUDY

This study examined the modulating effects of Clematis chinensis Osbeck (Ranunculaeae) on pro-inflammatory and degradative mediators associated with inflammatory arthritis.

MATERIALS AND METHODS

Primary human chondrocytes (PHC) were stimulated with IL-1β or lipopolysaccharide (LPS) to induce the enhanced release of prostaglandin E(2) (PGE(2)), metalloproteinase (MMP-3 and -13), and cyclooxygenase-2 (COX-2) protein expression. The (18)F-FDG microPET imaging system was used to evaluate the anti-arthritic effects of Clematis chinensisin vivo.

RESULTS

The acetone extracted Clematis chinensis (CC6) contained the most total saponins compared to other solvent's extracts and showed significant and dose-dependent inhibitory effects on PGE(2), MMP-3, -13, and COX-2 productions by LPS-stimulated PHC. Furthermore, CC6 also exerted inhibitory effects on 2-(18)F-fluoro-2-deoxy-d-glucose ((18)F-FDG) uptake when assessed by positron emission tomography (PET) uptake in the joints and serum PGE(2) of rabbits with knee joints injected with LPS.

CONCLUSION

The results suggest the significant chondroprotective effects of Clematis chinensis are through its anti-inflammatory and MMPs inhibitory abilities. Meanwhile, we established a new analysis method to evaluate the Chinese herbal anti-arthritic effects.

Differential effects of salvinorin A on endotoxin-induced hypermotility and neurogenic ion transport in mouse ileum

BACKGROUND

Salvinorin A (SA) is the principal active ingredient of Salvia divinorum, with an established inhibitory action on gastrointestinal (GI) transit and colonic ion transport in mice. Under normal conditions, the effects of SA are mediated by kappa opioid (KOR) and cannabinoid (CB1 and CB2) receptors. However, the role of SA in pathophysiological conditions remains unresolved. The aim of this study was to characterize the in vitro and in vivo effects of SA on mouse ileum after endotoxin challenge.

METHODS

Changes in GI motility were studied in vitro, using smooth muscle preparations from the mouse ileum. In vivo, the fecal pellet output and small intestinal fluid content were measured. Neurogenic ion transport and intestinal permeability were examined using Ussing chambers. In addition, Western blot analysis of mucosa was performed and plasma nitrite/nitrate levels were determined.

KEY RESULTS

Salvinorin A inhibited endotoxin-induced ileal hypercontractility via KOR, CB1, and CB2 receptors. Neurogenic ion transport, which was significantly reduced after endotoxin challenge, was normalized by SA through a nitric oxide synthase (NOS)-dependent mechanism. Western blot analysis and plasma nitrite/nitrate level quantitation confirmed the involvement of NOS in the regulatory action of SA.

CONCLUSIONS & INFERENCES

This is the first report showing differential effects of SA on motor and secretory activity in mouse GI during endotoxemia. The outcomes of our study imply possible novel applications of SA and its analogs in the treatment of GI disorders.

A Chinese herb Tripterygium wilfordii Hook F in the treatment of rheumatoid arthritis: mechanism, efficacy, and safety

Tripterygium wilfordii Hook F (TwHF) is a Chinese herb with immunosuppressive effects and an established history of use in the treatment of rheumatoid arthritis (RA). Numerous preclinical studies have demonstrated that the extracts from the root of TwHF inhibit the expression of proinflammatory cytokines, proinflammatory mediators, adhesion molecules, and matrix metalloproteinases by macrophages, lymphocytes, synovial fibroblasts, and chondrocytes. TwHF also induces apoptosis in lymphocytes and synovial fibroblasts and inhibits their proliferation. Except numerous uncontrolled clinical trials, there are some prospective, double-blind, randomized, and placebo/sulfasalazine-controlled trials, also demonstrating greater improvement in RA disease activity by TwHF extract than placebo/sulfasalazine. Radiographic progression in RA may also be retarded by TwHF. Therefore, the immunosuppressive, cartilage protective, and anti-inflammatory effects of TwHF extracts are well demonstrated, and TwHF extract is an alternative disease modifying anti-rheumatic drug (DMARD) for the patients with RA refractory to conventional therapy.

The expression change of β-arrestins in fibroblast-like synoviocytes from rats with collagen-induced arthritis and the effect of total glucosides of paeony

AIM OF THE STUDY

To investigate the expression of β-arrestins in fibroblast-like synoviocytes (FLS) from collagen-induced arthritis (CIA) rats and the effect of total glucosides of paeony (TGP).

MATERIALS AND METHODS

TGP and glucosides of tripterygium wilfordii (GTW) were intragastriclly administrated to collagen-induced arthritis (CIA) rats after immunization. The secondary inflammatory reaction was evaluated by hind paw swelling, polyarthritis index and histopathological changes. Antibodies to type II collagen (CII) were determined by enzyme-linked immunosorbent assay (ELISA). Synoviocyte proliferations were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl (MTT) assay. The expression of β-arrestins in synoviocytes from CIA rats was measured by western blot.

RESULTS

The administration of TGP (25, 50, 100 mg/kg) depressed hind paw swelling and decreased the arthritis scores of CIA rats. TGP improved the pathologic manifestations of CIA. Serum anti-CII antibodies level increased significantly in CIA rats, while TGP had no effect on it. Fibroblast-like synoviocytes (FLS) proliferation was inhibited by TGP (50, 100 mg/kg). On d14, d28 after immunization, β-arrestins expression greatly up-regulated in synoviocytes from CIA rats and then returned to baseline levels on d42 after immunization. TGP (50, 100 mg/kg) significantly reduced the expression of β-arrestins.

CONCLUSION

An inflammatory process in vivo induces an up-regulation of β-arrestins in synoviocytes from CIA rats while TGP can inhibit this change, which might be one of the important mechanisms for TGP to produce a marked therapeutic effect on RA.

Non-NSAID over-the-counter (OTC) remedies for arthritis: good, bad or indifferent?

This overview looks at some of the issues involved with the ever-increasing availability of marketed non-prescription products, specifically claiming to treat the pain and inflammation of arthritis and other musculoskeletal problems.The question of whether the buyer is getting (any) value for their money cannot be answered without considering several key issues. These include: (a) reliability of claims; (b) placebo effect (but for how long?); (c) reliability of composition, and reproducibility (especially of natural products); (d) general safety; (e) interactions with other medications; (f) honest labelling (in the absence of stricter guidelines).A particularly difficult problem is to know how to recognise a 'drug of choice', particularly for such a multi-faceted disease as chronic arthritis, when there is so little information about the actual pharmacology/potential toxicity of these OTC products in the standard drug compendia and other readily available reference texts.This grey area can only be illuminated by (i) further introduction (and enforcement) of adequate standards/quality controls for products offered OTC; (ii) earliest prosecution of clinical trials to supercede unverified testimonial claims; (iii) appropriate funding to research/establish basic pharmacology of the active principles.In summary, more research, more regulation, and more realistic investment will be required to dispel present uncertainty about which non-NSAID drugs/nutriceuticals are indeed effective against arthritis/other forms of inflammation, and which are not.

RNA polymerase - an important molecular target of triptolide in cancer cells

Triptolide, a diterpenoid triepoxide, is the key biological component of Tripterygium wilfordii Hook. f. which was used in traditional Chinese medicine for centuries to treat inflammation and autoimmune diseases. Triptolide has shown potent activity in not only anti-inflammation and immune modulation, but also antiproliferative and proapoptotic activity in many different types of cancer cells. However, for a long time, the precise molecular target(s) of triptolide have remained elusive. Recently, several groups discovered that triptolide inhibited the activity of RNA polymerase. This review will focus on these breakthrough findings about the molecular target of triptolide and its implications for targeted-cancer therapeutics.

Triptolide inhibits Jak2 transcription and induces apoptosis in human myeloproliferative disorder cells bearing Jak2V617F through caspase-3-mediated cleavage of Mcl-1

The discovery of oncogene addiction in myeloproliferative disorders (MPDs) driven by the gain-of-function mutant Jak2V617F has attracted intense interest in targeted therapy for MPDs. In this report, we demonstrate that triptolide potently downregulated the transcription of Jak2 by inhibiting the activity of RNA polymerase. Triptolide inhibited the in vitro and in vivo growth of tumor cells harboring Jak2V617F. Triptolide induced abundant apoptosis with a prominent decline of Bcl-2, Bcl-X(L), survivin and Mcl-1. As well, triptolide induced caspase-3-dependent Mcl-1 cleavage, which may potentiate apoptosis. These findings suggest that triptolide is a promising agent to kill Jak2V617F-harboring cells.

Comparison of Tripterygium wilfordii Hook F versus sulfasalazine in the treatment of rheumatoid arthritis: a randomized trial

BACKGROUND

Extracts of the medicinal plant Tripterygium wilfordii Hook F (TwHF) have been used in China for centuries to treat a spectrum of inflammatory diseases.

OBJECTIVE

To compare the benefits and side effects of TwHF extract with those of sulfasalazine for the treatment of active rheumatoid arthritis.

DESIGN

Randomized, controlled trial. A computer-generated code with random, permuted blocks was used to assign treatment.

SETTING

2 U.S. academic centers (National Institutes of Health, Bethesda, Maryland, and University of Texas, Dallas, Texas) and 9 rheumatology subspecialty clinics (in Dallas and Austin, Texas; Tampa and Fort Lauderdale, Florida; Arlington, Virginia; Duncanville, Pennsylvania; Wheaton and Greenbelt, Maryland; and Lansing, Michigan).

PATIENTS

121 patients with active rheumatoid arthritis and 6 or more painful and swollen joints.

INTERVENTION

TwHF extract, 60 mg 3 times daily, or sulfasalazine, 1 g twice daily. Patients could continue stable doses of oral prednisone or nonsteroidal anti-inflammatory drugs but had to stop taking disease-modifying antirheumatic drugs at least 28 days before randomization.

MEASUREMENTS

The primary outcome was the rate of achievement of 20% improvement in the American College of Rheumatology criteria (ACR 20) at 24 weeks. Secondary end points were safety; radiographic scores of joint damage; and serum levels of interleukin-6, cholesterol, cortisol, and adrenocorticotropic hormone.

RESULTS

Outcome data were available for only 62 patients at 24 weeks. In a mixed-model analysis that imputed data for patients who dropped out, 65.0% (95% CI, 51.6% to 76.9%) of the TwHF group and 32.8% (CI, 21.3% to 46.0%) of the sulfasalazine group met the ACR 20 response criteria (P=0.001). Patients receiving TwHF also had significantly higher response rates for ACR 50 and ACR 70 in mixed-model analyses. Analyses of only completers showed similar significant differences between the treatment groups. Significant improvement was demonstrated in all individual components of the ACR response, including the Health Assessment Questionnaire disability score. Interleukin-6 levels rapidly and significantly decreased in the TwHF group. Although not statistically significant, radiographic progression was lower in the TwHF group. The frequency of adverse events was similar in both groups.

LIMITATIONS

Only 62% and 41% of patients continued receiving TwHF extract and sulfasalazine, respectively, during the 24 weeks of the study. Long-term outcome data were not collected on participants who discontinued treatment.

CONCLUSION

In patients who continued treatment for 24 weeks and could also use stable oral prednisone and nonsteroidal anti-inflammatory drugs, attainment of the ACR 20 response criteria was significantly greater with TwHF extract than with sulfasalazine.

Anti-inflammatory mechanism of total glycosides of Acanthopanax Giraldii

OBJECTIVE

To study the anti-inflammatory mechanisms of total glycosides of Acanthopanax Giraldii (TGA).

METHODS

The changes of prostaglandin E(2)(PGE(2)), tumor necrosis factor (TNF-alpha), nitric oxide (NO), and expressions of COX-1 mRNA and COX-2 mRNA in BALB/c mouse macrophages were observed by the radioimmunoassay, ELISA and nitric acid reduction and RT-PCR in the presence or absence of TGA.

RESULTS

(1) TGA could significantly decrease the production of PGE(2)and NO in mouse peritoneal macrophages. The inhibitory rate to LPS-induced PGE(2)production was 87% (TGA 100 mg/L, P<0.05, vs. LPS) and 62% (TGA 20 mg/L, P<0.05, vs. LPS), respectively. The inhibitory rate of NO production in mouse peritoneal macrophages was 49% (TGA 100 mg/L, P<0.05, vs. LPS) and 21% (TGA 20 mg/L, P<0.05 vs. LPS), respectively. TGA could not inhibit LPS-induced TNF-alpha production in mouse peritoneal macrophages. (2) TGA also inhibited the expression of COX-1 and COX-2 mRNA in RAW264.7 cells. The inhibitory rate of TGA to COX-1 mRNA was 22% (TGA 100 mg/L, P<0.05, vs. blank). The inhibitory rate of TGA to COX-2 mRNA was 55% (TGA 20 mg/L, P<0.05, vs. LPS) and 100% (TGA 100 mg/L, P<0.01 vs. LPS), respectively.

CONCLUSION

The anti-inflammatory mechanisms of TGA for inhibiting the production of NO and PGE(2)are through inhibiting COX-2 mRNA expression without TNF-alpha changes.

Activity of triptolide against human mast cells harboring the kinase domain mutant KIT

Gain-of-function mutations of the receptor tyrosine kinase KIT can cause systemic mastocytosis (SM) and gastrointestinal stromal tumors. Most of the constitutively active KIT can be inhibited by imatinib; D816V KIT cannot. In this study, we investigated the activity of triptolide, a diterpenoid isolated from the Chinese herb Tripterygium wilfordii Hook. f., in cells expressing mutant KIT, including D816V KIT. Imatinib-sensitive HMC-1.1 cells harboring the mutation V560G in the juxtamembrane domain of KIT, imatinib-resistant HMC-1.2 cells harboring both V560G and D816V mutations, and murine P815 cells, were treated with triptolide, and analyzed in terms of growth, apoptosis, and signal transduction. The in vivo antitumor activity was evaluated by using the nude mouse xenograft model. Our results demonstrated that triptolide potently inhibits the growth of both human and murine mast cells harboring not only imatinib-sensitive KIT mutation but also imatinib-resistant D816V KIT. Triptolide markedly inhibited KIT mRNA levels and strikingly reduced the levels of phosphorylated and total Stat3, Akt, and Erk1/2, downstream targets of KIT. Triptolide triggered apoptosis by inducing depolarization of mitochondrial potential and release of cytochrome c, downregulation of Mcl-1 and XIAP. Furthermore, triptolide significantly abrogated the growth of imatinib-resistant HMC-1.2 cell xenografts in nude mice and decreased KIT expression in xenografts. Our data demonstrate that triptolide inhibits imatinib-resistant mast cells harboring D816V KIT. Further investigation of triptolide for treatment of human neoplasms driven by gain-of-function KIT mutations is warranted.

Triptolide Attenuates Endotoxin- and Staphylococcal Exotoxin-Induced T-Cell Proliferation and Production of Cytokines and Chemokines

Proinflammatory cytokines mediate the toxic effects of superantigenic staphylococcal exotoxins (SE) and bacterial lipopolysaccharide (LPS). Triptolide, an oxygenated diterpene derived from a traditional Chinese medicinal herb, Tripterygium wilfordii, inhibited SE-stimulated T-cell proliferation (by 98%) and expression of interleukin 1beta, interleukin 6, tumor necrosis factor, gamma interferon, monocyte chemotactic protein 1, macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta by human peripheral blood mononuclear cells (PBMC). It also blocked the production of these cytokines and chemokines by LPS-stimulated PBMC in a dose-dependent manner. These results suggest that triptolide has potent immunosuppressive effects even counteracting the effects of superantigens and LPS. It also may be therapeutically useful for mitigating the pathogenic effects of these microbial products by downregulating the signaling pathways activated by both bacterial exotoxins and endotoxins.

Effective therapy for nephritis in (NZB x NZW)F1 mice with triptolide and tripdiolide, the principal active components of the Chinese herbal remedy Tripterygium wilfordii Hook F

OBJECTIVE

Triptolide and tripdiolide are thought to be active components of the Chinese antirheumatic herbal remedy Tripterygium wilfordii Hook F, which has been shown to be effective in treating murine lupus nephritis. This study was undertaken to examine the therapeutic effect of triptolide and tripdiolide on established lupus nephritis in (NZB x NZW)F1 mice.

METHODS

(NZB x NZW)F1 mice were treated with vehicle, triptolide, or tripdiolide for 15 weeks beginning at the age of 29 weeks (after the development of lupus nephritis). Body weight, proteinuria, and anti-double-stranded DNA (anti-dsDNA) antibodies were monitored, and the kidney and spleen were assessed histologically. Culture supernatants of spleen mononuclear cells were assayed for cytokines.

RESULTS

By 28 weeks, most (NZB x NZW)F1 mice had developed lupus nephritis. Vehicle-treated mice exhibited progressive proteinuria, hypoalbuminemia, elevated blood urea nitrogen (BUN) levels, and evidence of severe nephritis. In contrast, proteinuria and BUN levels were significantly reduced in mice treated with either triptolide or tripdiolide as compared with those treated with vehicle. There was no hypoalbuminemia or apparent evidence of lupus nephritis in mice treated with either of the 2 diterpenoids. At 44 weeks of age, the survival rate in mice treated with vehicle (35.7%) was markedly lower than that in mice treated with either triptolide (87.5%) or tripdiolide (88.2%). The mean level of anti-dsDNA antibody in mice treated with tripdiolide was lower than that in the vehicle-treated mice upon completion of the treatment course. Production of tumor necrosis factor, interleukin-6, and monocyte chemoattractant protein 1 by spleen cells was also decreased after diterpenoid therapy.

CONCLUSION

Therapy with triptolide or tripdiolide significantly ameliorated lupus nephritis in (NZB x NZW)F1 mice, reduced cytokine and chemokine production, and prolonged survival.

Bioavailable constituents/metabolites of pomegranate (Punica granatum L) preferentially inhibit COX2 activity ex vivo and IL-1beta-induced PGE2 production in human chondrocytes in vitro

Several recent studies have documented that supplementation with pomegranate fruit extract inhibits inflammatory symptoms in vivo. However, the molecular basis of the observed effects has not been fully revealed. Although previous studies have documented the inhibition of nitric oxide and cyclooxygenase (COX) activity in vitro by plant and fruit extracts added directly into the culture medium but whether concentrations of bioactive compounds sufficient enough to exert such inhibitory effects in vivo can be achieved through oral consumption has not been reported. In the present study we determined the effect of rabbit plasma obtained after ingestion of a polyphenol rich extract of pomegranate fruit (PFE) on COX enzyme activity ex vivo and the IL-1beta-induced production of NO and PGE2 in chondrocytes in vitro. Plasma samples collected before and 2 hr after supplementation with PFE were tested. Plasma samples collected after oral ingestion of PFE were found to inhibit the IL-1beta-induced PGE2 and NO production in chondrocytes. These same plasma samples also inhibited both COX-1 and COX-2 enzyme activity ex vivo but the effect was more pronounced on the enzyme activity of COX-2 enzyme. Taken together these results provide additional evidence of the bioavailability and bioactivity of compounds present in pomegranate fruit after oral ingestion. Furthermore, these studies suggest that PFE-derived bioavailable compounds may exert an anti-inflammatory effect by inhibiting the inflammatory cytokine-induced production of PGE2 and NO in vivo.

Differential effects of triptolide and tetrandrine on activation of COX-2, NF-kappaB, and AP-1 and virus production in dengue virus-infected human lung cells

Most virus infections induce cycloxygenase-2 (COX-2) expression and subsequent prostaglandin E₂ (PGE₂) production in cells, an inflammatory response that might be detrimental to virus replication and pathogenesis. This response in dengue virus infection remains to be elucidated. Triptolide and tetrandrine, compounds derived from two commonly used Chinese herbs, both demonstrate anti-inflammatory and immunosuppressive effects partly through modulation of COX-2 expression and, hence, may have antiviral effects. In this study, we examined, firstly, the immune response to dengue virus infection with respect to COX-2 expression and PGE₂ production in human lung cells (A549), liver cells (HepG2) and dendritic cells. Secondly, we assessed the potential antiviral effects of triptolide and tetrandrine on dengue virus infection vis-à-vis expression of COX-2, PGE₂, transcription factors, as well as virus production. We found that dengue virus infection enhanced COX-2 expression and PGE₂ production in A549 cells, similarly to the response in dendritic cells, but not in HepG2 cells. In dengue virus-infected A549 cells, nuclear factor κB (NF-κB) and activator protein 1 (AP-1) were also activated, and both were dose-dependently inhibited by triptolide (0.5–4 ng/ml). Tetrandrine (1–10 μM) had no similar immunosuppressive effects and, moreover, at higher concentrations, enhanced NF-κB and AP-1 activity, COX-2 expression and PGE₂ production. However, unexpectedly, tetrandrine, but not triptolide, dose-dependently suppressed dengue virus production in A549 cells, independent of PGE₂ level. Our findings imply that triptolide and tetrandrine may attenuate dengue virus infection in human lung cells, but through distinct pathways.

Triptolide impairs dendritic cell migration by inhibiting CCR7 and COX-2 expression through PI3-K/Akt and NF-kappaB pathways

Inhibition of dendritic cell (DC) migration into tissues and secondary lymphoid organs is an efficient way to induce immunosuppression and tolerance. CCR7 and PGE(2) are critical for DC migration to secondary lymphoid organs where DC initiate immune response. Triptolide, an active component purified from the medicinal plant Tripterygium Wilfordii Hook F., is a potent immunosuppressive drug capable of prolonging allograft survival in organ transplantation by inhibiting T cell activation and proliferation. Considering the essential role in T cell tolerance of DC migration to secondary lymphoid organs, here we demonstrate that triptolide can significantly inhibit LPS-triggered upregulation of CCR7 expression and PGE(2) production by inhibiting cyclooxygenase-2 (COX-2) expression in DC, thus impairing DC migration towards CCR7 ligand CCL19/MIP-3betain vitro. Moreover, triptolide-treated DC display impaired migration into secondary lymphoid organs and in vivo administration of triptolide also inhibits DC migration. Further studies show that the triptolide-mediated inhibitory effects of LPS-induced activation of phosphatidylinositol-3 kinase (PI3-K)/Akt and nuclear NF-kappaB activation are involved in down-regulation of COX-2 and CCR7 expression resulting in impaired migration to secondary lymphoid organs of DC. Therefore, inhibition of DC migration through decreasing COX-2 and CCR7 expression via PI3-K/Akt and NF-kappaB signal pathways provides additional mechanistic explanation for triptolide's immunosuppressive effect.

Triptolide, a diterpenoid triepoxide, suppresses inflammation and cartilage destruction in collagen-induced arthritis mice

Chinese herbal remedy Tripterygium wilfordii Hook. f. (TWHF) has been reported to be therapeutically efficacious in the treatment of rheumatoid arthritis (RA), but its in vivo actions have not been clarified. The purpose of this study was to investigate the effects of triptolide, a diterpenoid triepoxide extracted from TWHF, on inflammation and cartilage destruction in collagen-induced arthritis (CIA) model mice. Histological examination demonstrated that triptolide significantly reduced the inflammatory responses and cartilage damage in the joint tissues. Interestingly, triptolide interfered with CIA-augmented expression of matrix metalloproteinases-13 and -3, which are considered to be key enzymes in the pathological destruction of cartilage, and simultaneously augmented CIA-reduced tissue inhibitors of metalloproteinases-1 and -2 expression in the joints. Moreover, triptolide inhibited prostaglandin E(2) production via selective suppression of the production and gene expression of cyclooxygenase (COX)-2, but not COX-1. The levels of interleukin (IL)-1beta, tumor necrosis factor alpha and IL-6 were also decreased by triptolide in the joint tissues and sera as well as the suppression of CIA-mediated expression of their mRNAs in the joints. In addition, triptolide treatment in vivo was able to reduce an abundance of nuclear factor-kappaB, the transcriptional factor closely related to the inflammatory process, in articular cartilage and synovium in CIA mice. These results suggest that triptolide exerts novel chondroprotective and anti-inflammatory effects on RA, and the therapeutic action of TWHF on RA is, in part, due to the triptolide activities.

Triptolide inhibits CC chemokines expressed in rat adjuvant-induced arthritis

Triptolide, a diterpenoid triepoxide from Tripterygium wilfordii Hook F (TWHF), has been proven to have potent immunosuppressive and anti-inflammatory activities. It has been clinically used to treat patients with rheumatoid arthritis (RA), in which chemokines play an important role in immune and inflammatory responses. To investigate the effect of triptolide on MCP-1, MIP-1alpha and RANTES, we used complete Freund's adjuvant to induce adjuvant-induced arthritis (AA) in rats. AA in rat is a useful experimental model of human RA. Our data show that the thickness of arthritic ankle decreases with administration of triptolide. Both mRNA and protein levels of MCP-1, MIP-1alpha and RANTES in synovial tissue of rats with AA are significantly higher than those in normal rats. mRNA levels of MIP-1alpha and RANTES increase in peripheral blood mononuclear cells of rats with AA in comparison with those in normal rats, whereas no MCP-1 mRNA can be detected. Triptolide can significantly inhibit rat AA induced over-expression of MCP-1, MIP-1alpha and RANTES at both mRNA and protein levels in a dose-dependent manner. These results may contribute to the therapeutic effects of triptolide in rheumatoid arthritis.

Triptolide inhibits COX-2 expression via NF-kappa B pathway in astrocytes

Previous investigations have showed that triptolide possessed potent anti-inflammatory and immunosuppressive properties. In the present study, we examined the protective effects of triptolide on the inflammatory response induced by bacterial lipopolysaccharide (LPS) both in vivo and in vitro. Intrahippocampal injection of LPS (4 microg) in rats significantly increased the immunoreactivity of glial fibrillary acid protein (GFAP) and cyclooxygenase-2 (COX-2) in the injected region, which was reduced by pretreatment with triptolide (10-50 microg/kg) for 5d. In the cultured human differentiated A172 astroglial cells, LPS (1mg/L) increased the expression of COX-2 mRNA and protein, the production of prostaglandin E(2) (PGE(2)) and the DNA binding activity of NF-kappa B, which were markedly attenuated by pretreatment with triptolide (0.2-5 microg/L) for 1h. These results suggested that the protective effect of triptolide on neuroinflammation is mediated by decreasing COX-2 expression, at least partly, via the inhibition of NF-kappa B signaling pathway.

A systematic review of randomised clinical trials of Tripterygium wilfordii for rheumatoid arthritis

Tripterygium wilfordii is a Chinese herb with immunosuppressive effects and an established history of use in the treatment of rheumatoid arthritis (RA). We have carried out a systematic review of randomised clinical trials (RCTs) which assess the effectiveness of T. wilfordii in this indication. We included only randomised and controlled studies which tested the effectiveness of T. wilfordii monopreparations in the treatment of RA. Studies in any language were included. A search of five electronic databases from inception to February 2005 identified 18 articles which could potentially meet our inclusion criteria. Only 16 of these could be retrieved from the scientific literature and after reading these in full, only two unique RCTs meeting our inclusion criteria were identified. Both indicated that T. wilfordii has beneficial effects on the symptoms of RA. However, the literature indicates that T. wilfordii is associated with serious adverse events which make the risk-benefit analysis for this herb unfavourable. Therefore, we cannot recommend its use.