F. Zijlstra

Evidence for local inflammation in complex regional pain syndrome type 1

BACKGROUND: The pathophysiology of complex regional pain syndrome type 1 (CRPS 1) is still a matter of debate. Peripheral afferent, efferent and central mechanisms are supposed. Based on clinical signs and symptoms (e.g. oedema, local temperature changes and chronic pain) local inflammation is suspected. AIM: To determine the involvement of neuropetides, cytokines and eicosanoids as locally formed mediators of inflammation. METHODS: In this study, nine patients with proven CRPS 1 were included. Disease activity and impairment was determined by means of a Visual Analogue Scale, the McGill Pain Questionnaire, the difference in volume and temperature between involved and uninvolved extremities, and the reduction in active range of motion of the involved extremity. Venous blood was sampled from and suction blisters made on the involved and uninvolved extremities for measurement of cytokines interleukin (IL)-6, II-1beta and tumour necrosis factor-alpha (TNF-alpha), the neuropetides NPY and CRGP, and prostaglandin E2RESULTS: The patients included in this study did have a moderate to serious disease activity and impairment. In plasma, no changes of mediators of inflammation were observed. In blister fluid, however, significantly higher levels of IL-6 and TNF-alpha in the involved extremity were observed in comparison with the uninvolved extremity. CONCLUSIONS: This is the first time that involvement of mediators of inflammation in CRPS 1 has been so clearly and directly demonstrated. This observation opens new approaches for the succesful use and development of immunosuppressives in CRPS 1.

Treatment of Vulvar Intraepithelial Neoplasia with Topical Imiquimod

BACKGROUND Alternatives to surgery are needed for the treatment of vulvar intraepithelial neoplasia. We investigated the effectiveness of imiquimod 5% cream, a topical immune-response modulator, for the treatment of this condition. METHODS Fifty-two patients with grade 2 or 3 vulvar intraepithelial neoplasia were randomly assigned to receive either imiquimod or placebo, applied twice weekly for 16 weeks. The primary outcome was a reduction of more than 25% in lesion size at 20 weeks. Secondary outcomes were histologic regression, clearance of human papillomavirus (HPV) from the lesion, changes in immune cells in the epidermis and dermis of the vulva, relief of symptoms, improvement of quality of life, and durability of response. Reduction in lesion size was classified as complete response (elimination), strong partial response (76 to 99% reduction), weak partial response (26 to 75% reduction), or no response (< or =25% reduction). The follow-up period was 12 months. RESULTS Lesion size was reduced by more than 25% at 20 weeks in 21 of the 26 patients (81%) treated with imiquimod and in none of those treated with placebo (P<0.001). Histologic regression was significantly greater in the imiquimod group than in the placebo group (P<0.001). At baseline, 50 patients (96%) tested positive for HPV DNA. HPV cleared from the lesion in 15 patients in the imiquimod group (58%), as compared with 2 in the placebo group (8%) (P<0.001). The number of immune epidermal cells increased significantly and the number of immune dermal cells decreased significantly with imiquimod as compared with placebo. Imiquimod reduced pruritus and pain at 20 weeks (P=0.008 and P=0.004, respectively) and at 12 months (P=0.04 and P=0.02, respectively). The lesion progressed to invasion (to a depth of <1 mm) in 3 of 49 patients (6%) followed for 12 months (2 in the placebo group and 1 in the imiquimod group). Nine patients, all treated with imiquimod, had a complete response at 20 weeks and remained free from disease at 12 months. CONCLUSIONS Imiquimod is effective in the treatment of vulvar intraepithelial neoplasia. (Current Controlled Trials number, ISRCTN11290871 [controlled-trials.com].).

Anti-inflammatory actions of acupuncture

Acupuncture has a beneficial effect when treating many diseases and painful conditions, and therefore is thought to be useful as a complementary therapy or to replace generally accepted pharmacological intervention. The attributive effect of acupuncture has been investigated in inflammatory diseases, including asthma, rhinitis, inflammatory bowel disease, rheumatoid arthritis, epicondylitis, complex regional pain syndrome type 1 and vasculitis. Large randomised trials demonstrating the immediate and sustained effect of acupuncture are missing. Mechanisms underlying the ascribed immunosuppressive actions of acupuncture are reviewed in this communication. The acupuncture-controlled release of neuropeptides from nerve endings and subsequent vasodilative and anti-inflammatory effects through calcitonine gene-related peptide is hypothesised. The complex interactions with substance P, the analgesic contribution of beta-endorphin and the balance between cell-specific pro-inflammatory and anti-inflammatory cytokines tumour necrosis factor-alpha and interleukin-10 are discussed.

Increased endothelin-1 and diminished nitric oxide levels in blister fluids of patients with intermediate cold type complex regional pain syndrome type 1

BackgroundIn complex regional pain syndrome type 1 (CRPS1) pro-inflammatory mediators and vascular changes play an important role in the sustained development and outcome of the disease. The aim of this study was to determine the involvement of vasoactive substances endothelin-1 (ET-1) and nitric oxide (NO) during early chronic CRPS1.MethodsIncluded were 29 patients with CRPS 1 who were diagnosed during the acute stage of their disease and observed during follow-up visits. Disease activity and impairment were determined and artificial suction blisters were made on the CRPS1 and the contralateral extremities for measurements of IL-6, TNF-α, ET-1 and nitrate/nitrite (NOx).ResultsThe levels of IL-6, TNF-α and ET-1 in blister fluid in the CRPS1 extremity versus the contralateral extremity were significantly increased and correlated with each other, whereas NOx levels were decreased.ConclusionThe NOx/ET-1 ratio appears to be disturbed in the intermediate stage of CRPS, resulting in vasoconstriction and consequently in a diminished tissue blood distribution.

Interleukin-1 receptors on rat brain endothelial cells: a role in neuroimmune interaction?

Inflammation following an infection induces a range of nonspecific symptoms of sickness in animals and humane. The cytokine interleukin‐1 (IL‐1) mediates many of the brain‐mediated symptoms of sickness. Binding sites for IL‐1 have been found in mouse brain, but not in the brains of rats. This raises questions as to the involvement of these neuronally localized IL‐1 binding sites in the induction of sickness symptoms. Based on observations of IL‐1 receptor mRNA in close vicinity to the vasculature in the mouse and rat brain, we studied the possibility that endothelial cells in the rat brain exhibit IL‐1 receptors to transduce information to the brain. Ligand binding studies reveal that cultured endothelial cells of adult rat brain exhibit specific binding sites for rat IL‐ 1β. Polymerase chain reaction experiments demonstrated that mRNA of the type I but not that of the type II IL‐1 receptor is present in rat brain endothelial cells. Incubation of these endothelial cells with recombinant rat IL‐1β showed a dose‐dependent increase in interleukin‐6, prostaglandin E2, and prostacyclin secretion. Intravenous administration of rat IL‐1β to adult rats enhanced prostaglandin E2 immunoreactivity in en‐dothelial cells of the brain microvasculature. These results indicate that functional type I IL‐1 receptors are present on endothelial cells of adult rat brain. We postulate that circulating IL‐1 can be translated by brain endothelial cells into other signals such as interleukin‐6 or prostaglandins that have access to the brain and induce sickness symptoms.—Van Dam, A.‐M., de Vries, H. E., Kuiper, J., Zijlstra, F. J., de Boer, A. G., Tilders, F. J. H., Berkenbosch, F. Interleukui‐1 receptors on rat brain endothelial cells: a role in neuroimmune interaction? FASEB J. 10, 351‐356 (1996)

Multiplex bead array assay for detection of 25 soluble cytokines in blister fluid of patients with complex regional pain syndrome type 1.

Inflammatory processes are known to be involved at least in the early phase of complex regional pain syndrome type 1 (CRPS1). Blister fluid obtained from the involved extremities displayed increased amounts of proinflammatory cytokines IL-6 and TNFα compared with the noninvolved extremities. The aim of this paper is to investigate the involvement of mediators by measurement of several other cytokines using new detection techniques that enable multiple cytokine measurement in small samples. The use of a multiplex-25 bead array cytokine assay and Luminex technology enabled simultaneous measurement of representative (1) proinflammatory cytokines such as GM-CSF, IL-1β, IL-1RA, IL-6, IL-8, and TNF-α; (2) Th1/Th2 distinguishing cytokines IFN-γ, IL-2, IL-2R, IL-4, IL-5, and IL-10; (3) nonspecific acting cytokines IFN-α, IL-7, IL-12p40/p70, IL-13, IL-15, and IL-17; and (4) chemokines eotaxin, IP-10, MCP-1, MIP-1α, MIP-1β, MIG, and RANTES. Although minimal detection levels are significantly higher in the bead array system than those in common ELISA assays, in blister fluid, IL-1RA, IL-6, IL-8, TNF-α, IL-12p40/p70, MCP-1, and MIP-1β were detectable and increased in CRPS1 affected extremities. Levels of IL-6 and TNF-α simultaneously measured by ELISA (Sanquin Compact kit) and by multiplex-25 bead array assay (Biosource) were highly correlated (r = 0.85, P < .001 for IL-6 and r = 0.88, P < .001 for TNF-α). Furthermore, IP-10 and eotaxin were detectable but diminished in CRPS1, whereas detectable amounts of IL-10 were similar in involved and noninvolved extremities. Multiplex bead array assays are useful systems to establish the involvement of cytokines in inflammatory processes by measurements in blister fluids of CRPS1. Ten representative cytokines were detectable. However, detection levels and amounts measured are at least 3 times higher in the multiplex-25 array assay than in the ELISA assays used simultaneously for the measurement of cytokines.

Quantification of global left ventricular function : Comparison of multidetector computed tomography and magnetic resonance imaging. A meta-analysis and review of the current literature

Cardiac morbidity and mortality are closely related to cardiac volumes and global left ventricular (LV) function, expressed as left ventricular ejection fraction. Accurate assessment of these parameters is required for the prediction of prognosis in individual patients as well as in entire cohorts. The current standard of reference for left ventricular function is analysis by short-axis magnetic resonance imaging. In recent years, major extensive technological improvements have been achieved in computed tomography. The most marked development has been the introduction of the multidetector CT (MDCT), which has significantly improved temporal and spatial resolutions. In order to assess the current status of MDCT for analysis of LV function, the current available literature on this subject was reviewed. The data presented in this review indicate that the global left ventricular functional parameters measured by contemporary multi-detector row systems combined with adequate reconstruction algorithms and post-processing tools show a narrow diagnostic window and are interchangeable with those obtained by MRI.

Intermediate Stage Complex Regional Pain Syndrome Type 1 Is Unrelated to Proinflammatory Cytokines

The aim of this paper is to determine the involvement of tumour necrosis factor-α (TNF-α) and interleukin (IL)-6 in intermediate CRPS 1 as locally formed mediators of inflammation. In this study, 25 patients with proven CRPS 1 (Bruehl criteria) were included. All patients participated in one of our earlier studies during the acute stage of their disease. After the disease developed into an intermediate stage, both the disease activity and the profile of inflammatory mediators were reevaluated. Disease activity and impairment were determined by means of a visual analogue scale, the McGill Pain Questionnaire, the difference in volume and temperature between the involved and uninvolved extremities, and the reduction in active range of motion of the involved extremity. Suction blisters were made on the involved and uninvolved extremities for measurement of IL-6 and TNF-α. A significant improvement in signs and symptoms of impairment was found. However, the levels of IL-6 and TNF-α in blister fluid in the involved extremity versus uninvolved extremity were still significantly raised. Although signs and symptoms are significantly improved, proinflammatory cytokines are still increased in CRPS 1 affected extremities during the intermediate stage of the disease. This indicates that the initiation and sustained development of the disease are only partially affected by proinflammatory cytokines. Follow-up in the chronic stage is necessary to draw more definite conclusions about the existence of a supposed relation between clinical signs and symptoms and the level of proinflammatory cytokines.

Nicotine inhibits the in vitro production of interleukin 2 and tumour necrosis factor-α by human mononuclear cells

Smoking protects against ulcerative colitis (UC), and treatment with nicotine patches has a beneficial symptomatic effect in patients with UC. To find an explanation for this response to nicotine in UC, we assessed the effects of nicotine on cytokine production by mononuclear cells (MNC). MNC were isolated from peripheral blood from healthy volunteers. Non-adherent MNC were preincubated with varying concentrations of nicotine or prednisolone for 24 h followed by addition of phytohemagglutinin (10 micrograms/ml). The concentrations of interleukin 2 (IL-2) and tumour necrosis factor-alpha (TNF alpha) in the supernatants were determined by ELISA. Nicotine as well as prednisolone caused a significant inhibition of IL-2 and TNF alpha production. The maximum inhibition caused by nicotine was about 50% of that caused by prednisolone and was reached at concentrations equivalent to nicotine levels measured in plasma of smokers. These results indicate that nicotine exerts its immunoregulatory role through modulation of the cytokine production by non-adherent mononuclear cells.

Identification of prostaglandin D2 as the major eicosanoid from liver endothelial and Kupffer cells

The capacity of freshly isolated endothelial, Kupffer and parenchymal rat liver cells to produce eicosanoids from [1-14C]arachidonic acid was investigated in order to determine the relative importance of these cells to total liver eicosanoid production. Based upon the total formation of [1-14C]arachidonate metabolites in the liver, it can be calculated that Kupffer and endothelial cells are responsible for 65 and 23%, respectively, of the total amount of eicosanoids produced by the liver. Consequently, parenchymal liver cells, representing 92.5% of the total liver mass, contribute only 12% to the total liver production of eicosanoids. The main product of Kupffer cells was prostaglandin D2 (PGD2), representing 55% of the total amount of eicosanoids produced. Liver endothelial cells produced about 4-times less eicosanoids (per mg cell protein) than Kupffer cells, and PGD2 was also the main product of these cells (44%). The production of eicosanoids by parenchymal cells was lower by a factor of 180 (per mg cell protein) than that in Kupffer cells. Besides the ability to form eicosanoids from added 14C-labeled arachidonic acid, Kupffer and endothelial liver cells were also able to produce significant amounts of PGD2 (the main liver prostaglandin) from endogenous arachidonic acid, as determined by a radioimmunoassay. It is concluded that inside the liver, Kupffer cells together with endothelial cells are of major importance in the production of eicosanoids, while the parenchymal cells may be considered metabolic target cells for these products, as indicated by the finding that the major liver prostaglandin, PGD2, could stimulate the glucose output in isolated parenchymal cells.