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Several lines of evidence in experimental animals indicate that the kinin system may participate in the pathogenesis of envenomation by the Tityus serrulatus (Ts) scorpion sting, but there are no studies in humans with regard to this system. In this study, we evaluated the plasma levels of high-molecular (HKg) and low-molecular (LKg) weight kininogens (detected by ELISA), the activities of plasma or tissue kallikreins and kininase II (enzymatic action upon selective substrates), and the Ts plasma venom levels (ELISA). A total of 27 patients (12 males) aged 12–72 were evaluated immediately at hospital admittance. According to the severity of envenomation, patients were classified as mild (n = 15), moderate (n = 8), and severe cases (n = 4). Controls were paired for age and sex. Plasma venom levels were associated with the severity of envenomation. Severe cases presented lower levels of LKg in relation to mild and controls. Inverse correlations were seen between LKg levels and the venom concentration. The results of this study suggested that the kinin system may participate in the pathogenesis of human Ts envenomation and knowledge about this system may be useful to develop new strategies to reduce the damage caused by scorpion envenomation.

To investigate the influence of rheumatoid arthritis on the stereoselective disposition of fenoprofen administered as a racemic mixture, eight patients with rheumatoid arthritis receiving calcium rac-fenoprofen (200 mg/8 h) and 7 healthy volunteers given single oral dose (600 mg) were investigated. Serial blood samples and urine were collected from zero to 24 h after fenoprofen (FEN) administration. The following differences were observed between the (+)-(S) and (−)-(R)-FEN in the patients with rheumatoid arthritis (means 95% CI, Wilcoxon test, P < 0.05): Cmax 14.1 (12.5–15.8) versus 3.6 (2.5–4.7) μg/ml; AUC 80.5 (67.3–93.7) versus 12.1 (8.8–15.4) μg·h/ml; ClT/f 1.3 (1.0–1.5) versus 9.1 (6.5–11.8) l/h; and t1/2 3.1 (2.3–3.9) versus 1.2 (0.8–1.6) h. The ClT/f of (−)-(R)-FEN was reduced in patients with rheumatoid arthritis when compared to healthy volunteers: 9.1 (6.5–11.8) versus 17.4 (13.9–20.9) l/h; P < 0.05 Mann–Whitney test. The administration of rac-FEN as a single dose to healthy volunteers or multiple doses to patients with rheumatoid arthritis resulted in lower ClT/f for the (+)-(S)-FEN. The lower ClT/f of (−)-(R)-FEN observed for patients with rheumatoid arthritis is consistent with lower clearance by inversion, although other metabolic pathways, drug interactions, and bioavailability of the individual enantiomers may also contribute to the difference. Chirality 16:602–608, 2004. © 2004 Wiley-Liss, Inc.

This study was aimed to investigate the influence of diabetes or arthritis on the enantioselective metabolism and kinetic disposition of fenoprofen in rats with streptozotocin-induced diabetes or Mycobacteriumtuberculosis adjuvant-induced arthritis. Animals received i.v. 10 mg/kg racemic fenoprofen and blood samples were collected up to 24 h thereafter, with 5 animals studied at each time point. Plasma concentrations of the fenoprofen enantiomers were determined by HPLC. Diabetic and arthritic animals showed significant differences when compared with respective controls for the following pharmacokinetic variables of the (+)-(S)-fenoprofen eutomer: area under the plasma concentration time curve, total clearance and volume of distribution. The results indicate that experimental diabetes and adjuvant-induced arthritis influence the fenoprofen enantioselective metabolism.

Scorpion envenomation is a common medical problem in many countries and an important cause of morbidity and mortality, especially among children. The plasma levels of pro-inflammatory (IL-1beta, IL-6, IL-8 and TNF-alpha) and anti-inflammatory (IL-10) cytokines were measured in individuals stung by Tityus serrulatus (Ts) scorpions. According to clinical manifestations patients were classified, as defined by the Brazilian Ministry of Health, as having mild (n=15, mean age=42.2 years), moderate (n=8, mean age=26 years) or severe (n=4, mean age=14 years) envenomation. Blood samples were taken immediately (T1) and 6h (T2) after admission to the hospital. Eighteen age-matched healthy volunteers were used as control. TNF-alpha, IL-1beta, IL-6 and IL-8 levels were significantly increased in moderate and severe cases and the levels of these cytokines were positively correlated with the severity of envenomation, as evaluated by clinical profile and plasma venom concentration. IL-10 levels were increased in severe and moderate cases and reduced in mild cases. The results reported in the present study suggest that the physiopathological manifestation of Ts envenomation may be mediated, at least in part, by cytokines, and that the early treatment after scorpion sting with drugs that inhibit cytokine production, such as glucocorticoids, may have a potential beneficial effect, ameliorating the severity of the clinical manifestations observed, particularly in severe and moderate cases.

Pruritic papular eruption (PPE) is a common inflammatory cutaneous lesion observed only in HIV/AIDS patients. Since kinin is an important mediator in inflammation, we evaluated the levels of total kininogen (TKg), low and high molecular weight kininogen (LKg and HKg, respectively) and the activity of kallikrein in plasma of 11 patients (median age = 31.4) with AIDS and PPE (PPE+), eight patients (median age = 31.5) with AIDS without PPE (PPE-) and in 12 control individuals (median age = 32.9) with anti-HIV negative serum. Kininogens were measured by ELISA and expressed in median (m) of BK Equivalent/ml plasma and the kallikrein by its activity upon selective chromogenic substrate, and expressed as U kallikrein/ml of plasma. TKg or LKg concentrations in PPE+ patients (m = 4.11 and 4.5) and in PPE- patients (m = 6.23 and 4.54) were significantly higher when compared to control (m = 2.10 and 1.17). Compared to controls PPE- patients presented similar values of HKg (m = 0.78 and 0.61), whereas PPE+ patients presented undetectable values. Plasma kallikrein activity was significantly decreased in PPE+ and PPE- (m = 0.6 and 0.89, respectively) when compared with control individuals (m = 2.23).

We studied some of the components of the kininogen-kallikrein-kinin system, simultaneously, in plasma and synovial effusions of patients with inflammatory articular diseases. Plasma and tissue kallikrein like activity and kininogen levels were evaluated. Active plasma and tissue kallikreins in plasma and synovial fluid were detected by their amidase activity upon specific chromogenic substrates. Kininogen levels were determined by a bioassay. Both specific amidase activity of plasma and tissue kallikreins were augmented in synovial effusions in relation to their own plasma activity. Kininogen levels in synovial fluid tended to be diminished in relation to plasma, however statistical significance was not reached. The consumption of kininogen is probably related to kinin production. This finding together with increased activities of plasma and tissue kallikreins reinforce the involvement of kinins in pathogenesis of inflammatory articular diseases.

We evaluated the activities of salivary kallikrein and tissue/plasma kallikreins, and the plasma levels of high-molecular (HKg) and low-molecular (LKg) weight kininogens in patients with rheumatoid arthritis. The patients exhibited higher levels of the active salivary kallikrein compared to the controls. In contrast, the total salivary kallikrein activity of patients was not different from controls. In plasma from the patients, tissue kallikrein activity or plasma prekallikrein activity was not significantly different from the controls. Plasma HKg levels observed in patients were higher than in controls, whereas plasma LKg levels did not differ significantly from controls. Our results showed that most of the salivary kallikrein seen in patients is in its active form, suggesting the presence of systemic or local factors with the ability to activate salivary pro-kallikrein.

The objective of the present study was to assess the influence of type 1 and type 2 diabetes mellitus on the enantioselective pharmacodynamics and pharmacokinetics of fenoprofen. Patients with diabetes mellitus type 1 (n = 7) or type 2 (n = 7) and healthy volunteers (n = 13) received orally a single 600-mg dose of racemic fenoprofen. Monocompartmental analysis of (+)-(S)-fenoprofen showed a significant difference (P < .05, Kruskal-Wallis test) in area under the curve (AUC) values (153.68 vs 243.50 microg x h/mL) and oral clearance (1.95 vs 1.23 L/h) only between patients with diabetes mellitus type 2 and healthy volunteers. The inhibitory activity of cyclooxygenases was evaluated indirectly by the determination of prostaglandin E2 (COX-2) and thromboxane B2 (COX-1) using the sigmoidal inhibitory Emax model. The patients with type 2 diabetes mellitus presented lower IC50 (3.29 vs 6.0 microg/mL) and g (0.73 vs 2.01) values for COX-1 activity compared to healthy volunteers (P < .05, Kruskal-Wallis test). These results show that diabetes mellitus type 2, but not type 1, influences the pharmacokinetics and pharmacodynamics of (+)-(S)-fenoprofen.

Summary Background Pemphigus foliaceus (PF) is an autoimmune blistering disease of unknown aetiology, which is endemic in Brazil. Although the pathogenesis of PF is still unknown, proteins of the contact system have been implicated. Objectives As the components of the kinin system may interact with those of the contact system, in this study we evaluated the plasma levels of high-molecular-weight kininogen (HK) and low-molecular-weight kininogen (LK), and the activity of plasma kallikrein, tissue kallikrein and kininase II in plasma of patients with PF presenting with Nikolsky's sign. As kidneys and salivary glands are relevant sources of tissue kallikrein for plasma, we also evaluated urinary/salivary kallikrein and urinary kininase II activities. Methods Fifteen patients and 15 age- and sex-matched controls were studied. Kininogen levels were determined by enzyme-linked immunosorbent assay, and the activities of kallikreins and kininase II were determined using selective chromogenic substrates. Results Compared with controls, plasma HK levels were decreased (P = 0·031), whereas the activities of plasma kallikrein, tissue kallikrein and kininase II in plasma, and the activity of salivary kallikrein, were increased in patients (P

To evaluate the kinin system components and selected cytokines in plasma and cerebrospinal fluid (CSF) of patients with neuropsychiatric lupus (NPL).We studied 29 women with active NPL and 29 healthy women matched to patients for age. Low (LKg) and high molecular weight kininogen (HKg) and cytokine concentrations [interleukin 1beta (IL-1beta), IL-6, IL-8, IL-10, and tumor necrosis factor-a (TNF-a)] were determined by ELISA. The activities of tissue kallikrein, plasma prekallikrein, and kininase II were assayed by their action on selective substrates.Compared to controls, patients with NPL presented increased plasma and CSF levels of LKg, HKg, and prekallikrein, increased activity of tissue kallikrein and kininase II, and increased levels of IL-6, IL-10, and TNF-a (p0.001 each comparison). IL-1beta levels were increased in patient plasma (p0.001), whereas plasma IL-8 levels did not differ from controls. IL-1beta and IL-8 were not detected in CSF of patients or controls.The increased levels of kininogen fractions, kallikreins, and kininase II in patient plasma and CSF indicate overactivity of the kinin system, suggesting intense kinin production. Since kinins may induce the production of proinflammatory cytokines including IL-1beta, IL-6, and TNF-a, these findings support the participation of kinins and cytokines in the acute manifestations of NPL. Most of the variables evaluated in patients' CSF increased proportionally in relation to plasma levels. In contrast, the activity of tissue kallikrein in patient CSF increased out of proportion to plasma levels, appearing to be locally synthesized in response to brain involvement.

The separation of albumin from salts and buffers by AG 11A8 ion-retardation resin was studied as a function of column length, ion load, flow rate, and resin regeneration. These operating conditions affected the retardation of the low molecular weight ions and, thus, improved the separation from albumin which was cluted rapidly. Experimental conditions are described for separating albumin from NaCl, Tris-HCl, sodium trichloroacetate, sodium 5-sulfosalicylate, sodium citrate, sodium acetate, sodium phosphate, and ammonium sulfats. A 200-cm column is necessary for the effective separation of the last four compounds from albumin. The resin was used to separate bradykinin and related peptides from salts and buffers present in ethanol extracts of trypsin-treated plasma, as reported in the accompanying paper (Reis, M. L., Draghetta, W., Camargo, A. C. M., and Greene, L. J. (1977) Anal. Biochem. 81 , 358–368.

A method employing a 200-cm column of AG 11A8 ion-retardation resin (Reis, M. L., Draghetta, W., and Greene, L. J., Anal. Biochem.81, 346–357) was used to separate nanomole quantities of bradykinin (Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg), Lys-bradykinin and Met-Lys-bradykinin from at least 99% of the salts present in an 80% ( v v ) ethanol extract of trypsin-treated acid-denatured plasma to which had been added sodium acetate, sodium citrate, and Tris-HCl. Pretreatment of the resin with polybrene or other basic polymers is necessary to prevent the irreversible adsorption to the resin of nanomole quantities of these basic polypeptides. The behavior of other peptides, glucose, and also amino acids on the long column of the resin has been studied. Extensive losses of both aromatic and basic amino acids have been observed.