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Background and purpose The entire kallikrein-kinin system is present in the skin, and it is thought to exert a relevant role in cutaneous diseases, including psoriasis. The present study was designed to evaluate the relevance of kinin receptors in the development and progression of a model of psoriasis in mice. Experimental approach The effects of kinin B1 and B2 receptor knockout and of kinin receptor antagonists (SSR240612C or FR173657) were assessed in a model of psoriasis induced by imiquimod in C57BL/6 mice. Severity of psoriasis was assessed by histological and immunohistochemical assays of skin, along with objective scores based on the clinical psoriasis area and severity index. Key results Both kinin receptors were up-regulated following 6 days of imiquimod treatment. Kinin B1 and B2 receptor deficiency and the use of selective antagonists show morphological and histological improvement of the psoriasis hallmarks. This protective effect was associated with a decrease in undifferentiated and proliferating keratinocytes, decreased cellularity (neutrophils, macrophages, and CD4+ T lymphocytes), reduced γδ T cells, and lower accumulation of IL-17. The lack of B2 receptors resulted in reduced CD8+ T cells in the psoriatic skin. Relevantly, blocking kinin receptors reflected the improvement of psoriasis disease in the well-being behaviour of the mice. Conclusions and implications Kinins exerted critical roles in imiquimod-induced psoriasis. Both B1 and B2 kinin receptors exacerbated the disease, influencing keratinocyte proliferation and immunopathology. Antagonists of one or even both kinin receptors might constitute a new strategy for the clinical treatment of psoriasis.

Malva sylvestris is a species used worldwide as an alternative to anti-inflammatory therapies; however, its mechanism of action remains unknown. In this paper, the anti-inflammatory effects of M. sylvestris alcoholic extracts were evaluated by measuring the pro-inflammatory mediators PGE₂ and PGD₂ in desferrioxamine-stimulated phorbol 12-myristate 13-acetate-differentiated U937 cells. An HPLC-DAD fingerprint of the M. sylvestris extract was performed and caffeic acid, ferulic acid and scopoletin were identified and quantified. An HPLC-MS/MS method was developed and validated to separate and measure the prostaglandins. The lower limits of detection (~0.5 ng/mL for PGE₂ and PGD₂) and quantification (1.0 ng/mL for PGE₂ and PGD₂) indicated that the method is highly sensitive. The calibration curves showed excellent coefficients of correlation (r > 0.99) over the range of 1.0-500.0 ng/mL, and at different levels, the accuracy ranged from 96.4 to 106.4% with an RSD < 10.0% for the precision study. This method was successfully applied using U937-d cells. A significant dose-dependent reduction of PGE2 and PGD2 levels occurred using 10 µg/mL (10.74 ± 2.86 and 9.60 ± 6.89%) and 50 µg/mL of extract (48.37 ± 3.24 and 53.06 ± 6.15%), suggesting that the anti-inflammatory mechanisms evoked by M. sylvestris may be related to modulation of these mediators.

Background and Objective It has been demonstrated that periodontitis induces systemic inflammation, which may impair endothelial function leading to increased cardiovascular risk. The aim of this study was to evaluate the effect of simvastatin on systemic inflammatory markers and endothelial dysfunction induced by periodontitis. Material and Methods Wistar rats were subjected to ligature-induced experimental periodontitis. Eight days after the procedure, the ligature and sham groups were randomly assigned to receive simvastatin or vehicle once a day until the 14th day, when the effects of acetylcholine and sodium nitroprusside on blood pressure were evaluated. Blood samples were collected and evaluated for plasma interleukin-6C, -reactive protein and lipids. The maxilla and mandible were removed for bone loss analysis. Results Simvastatin treatment reduced systemic inflammation and endothelial dysfunction induced by periodontitis. Furthermore, simvastatin improved the blood lipid profile and reduced alveolar bone loss. Conclusion Simvastatin treatment, in addition to the improvement on serum lipid profile, may reduce other predictors of cardiovascular events associated with periodontitis.

The marine snail peptide ziconotide (ω-conotoxin MVIIA) is used as an analgesic in cancer patients refractory to opioids, but may induce severe adverse effects. Animal venoms represent a rich source of novel drugs, so we investigated the analgesic effects and the side-effects of spider peptide Phα1β in a model of cancer pain in mice with or without tolerance to morphine analgesia. Cancer pain was induced by the inoculation of melanoma B16-F10 cells into the hind paw of C57BL/6 mice. After 14 days, painful hypersensitivity was detected and Phα1β or ω-conotoxin MVIIA (10-100 pmol/site) was intrathecally injected to evaluate the development of antinociception and side-effects in control and morphine-tolerant mice. The treatment with Phα1β or ω-conotoxin MVIIA fully reversed cancer-related painful hypersensitivity, with long-lasting results, at effective doses 50% of 48 (32-72) or 33 (21-53) pmol/site, respectively. Phα1β produced only mild adverse effects, whereas ω-conotoxin MVIIA induced dose-related side-effects in mice at analgesic doses (estimated toxic dose 50% of 30 pmol/site). In addition, we observed that Phα1β was capable of controlling cancer-related pain even in mice tolerant to morphine antinociception (100% of inhibition) and was able to partially restore morphine analgesia in such animals (56 ± 5% of inhibition). In this study, Phα1β was as efficacious as ω-conotoxin MVIIA in inducing analgesia in a model of cancer pain without producing severe adverse effects or losing efficacy in opioid-tolerant mice, indicating that Phα1β has a good profile for the treatment of cancer pain in patients.

Garcinia gardneriana is popularly used in skin disorders; therefore, this article investigated the effect of G. gardneriana extracts from leaves, bark and seeds and two isolated compounds in ear oedema and leucocytes migration caused by croton oil. The topical application of the extract of G. gardneriana leaves was able to reduce (70 ± 3%, and ID50 0.33 mg/ear) ear oedema, while the seeds (51 ± 5%) and the wood (60 ± 12%) extracts were less effective. In a time-course evaluation, the leaf extract (1 mg/ear) was effective when applied 2 hr before and until 3 hr after the stimulation, presenting a higher effectiveness when applied right after croton oil (83 ± 7% inhibition). In addition, the leaf extract was able to diminish the myeloperoxidase (MPO) activity in 64 ± 13%, which suggests the inhibition of leucocyte infiltration that was confirmed by histological analysis. Also, both biflavonoids isolated from the leaves of G. gardneriana, fukugetin (or morelloflavone) and 13-naringenin-II 8-eriodictyol (GB-2a), were able to reduce ear oedema, with ID50 values of 0.18 (0.10–0.28) and 0.22 (0.15–0.31) mg/ear, respectively, besides the inhibition of MPO activity of 52 ± 6% and 64 ± 5%, respectively. Using the fluorescent probe 2′,7′-dichlorodihydrofluorescein diacetate, the leaf extract, fukugetin and GB-2a topically applied to the ear treated with croton oil reduced 52 ± 15%, 63 ± 17% and 83 ± 4%, respectively, the production of reactive oxygen species of the skin. Thus, these results reveal the anti-inflammatory effect of G. gardneriana leaves for topical usage, and both biflavonoids are responsible for this effect.

Study Objective. To evaluate the efficacy and safety of using the anti-tumor necrosis factor-α (anti-TNF-α) drugs adalimumab, etanercept, and infliximab for the treatment of rheumatoid arthritis. Design. Systematic review and meta-analysis of 21 randomized, placebo-controlled trials (eight adalimumab, seven infliximab, six etanercept). Patients. Adults with rheumatoid arthritis who received adalimumab (1524 patients), infliximab (1116 patients), etanercept (1029 patients), or placebo (2834 patients) with or without concomitant methotrexate in all groups. Measurements and Main Results. A literature search of several databases from January 1995-December 2008 was performed. There were no restrictions based on language or date of publication, and low-quality studies (based on Jadad score) were excluded. American College of Rheumatology (ACR) 20% improvement criteria (ACR20), 50% improvement criteria (ACR50), and 70% improvement criteria (ACR70) were used to compare treatment efficacy. Safety was compared based on frequency of serious adverse events, serious infections, malignancy, and death. Withdrawals due to adverse events and lack of efficacy were also evaluated. With short-term treatment (12–30 wks), etanercept demonstrated the highest risk ratios (RRs) for reaching ACR20 and ACR50: 2.94 (95% confidence interval [CI] 2.27–3.81) and 5.28 (95% CI 3.12–8.92), respectively. Adalimumab demonstrated the highest RR for achieving ACR70 (5.36, 95% CI 3.76– 7.64). Over a long-term treatment course (1–3 yrs), adalimumab demonstrated the highest RRs (95% CIs) for these parameters: 1.85 (1.07–3.19), 2.80 (1.16–6.77), and 3.23 (1.37–7.61) for ACR20, ACR50, and ACR70, respectively. No statistically significant differences were noted in the safety of any of the three drugs compared with placebo. Infliximab had the highest RRs for withdrawing from the study due to lack of efficacy (2.05, 95% CI 1.33–3.16) and adverse events (0.41, 95% CI 0.18–0.95). Conclusion. With short-term treatment, etanercept and adalimumab had higher efficacy results; with long-term treatment, adalimumab appeared to be the most effective. Clinicians should be aware that each of the three drugs has different rates of efficacy and different safety considerations that must be taken into account when selecting the best treatment for an individual with rheumatoid arthritis.