T-kininogen inhibits kinin-mediated activation of ERK in endothelial cells

Serum levels of T-kininogen increase dramatically as rats approach the end of their lifespan. Stable expression of the protein in Balb/c 3T3 fibroblasts leads to a dramatic inhibition of cell proliferation, as well as inhibition of the ERK signaling pathway. T-kininogen is a potent inhibitor of cysteine proteinases, and we have described that the inhibition of ERK activity occurs, at least in part, via stabilization of the MAP kinase phosphatase, MKP-1. Since fibroblasts are not a physiological target of T-kininogen, we have now purified the protein from rat serum, and used it to assess the effect of T-kininogen on endothelial cells. Adding purified T-kininogen to EAhy 926 hybridoma cells resulted in inhibition of basal ERK activity levels, as estimated using appropriate anti-phospho ERK antibodies. Furthermore, exogenously added T-kininogen inhibited the activation of the ERK pathway induced by either bradykinin or T-kinin. We conclude that the age-related increase in hepatic T-kininogen gene expression and serum levels of the protein could have dramatic consequences on endothelial cell physiology, both under steady state conditions, and after activation by cell-specific stimuli. Our results are consistent with T-kininogen being an important modulator of the senescent phenotype in vivo

Evidence for the presence of a kininogen-like species in a case of total deficiency of low and high molecular weight kininogens

Low and high molecular weight kininogens (LK and HK), containing 409 and 626 amino acids with masses of ~65 and 120120 kDa after glycosylation, respectively, are coded by a single gene mapped to the human chromosome 3 by alternative splicing of the transcribed mRNA. The NH2-termini Glu(1)-Thr(383) region, identical in LK and HK, contains bradykinin (BK) moieties Arg(363)-Arg(371). LK, HK and their kinin products Lys-BK and BK are involved in several biological processes. They are evolutionarily conserved and only 7 patients, all apparently normal, have been reported to lack them. In one of these patients (Williams'trait), a codon mutation (Arg(178) r stop) has been blamed for the absence of LK and HK. However, using Western blots with 2 monoclonal anti-HK antibodies, one that recognizes the region common to LK and HK and the other that recognizes only HK, I detected ~110-kDa bands in the plasma of this LK/HK-deficient patient vs ~120-kDa bands in normal human and ape plasmas. With polyclonal anti-Lys-BK antibody, which strongly detects BK eleaved at its COOH-terminus in purified HK, I detected ~110-kDa bands in the normal and the deficient plasmas. Western blots with a monoclonal anti-prekallikrein (PK) antibody showed that surface activation of PK and distribution of PK activation products, both dependent on HK, were similar in these plasmas. These findings suggest that a mutant gene yielded a kininogen-like species possibly involving aberrant mRNA splicing - structurally different from normal HK, but apparently with the capacity to carry out seemingly vital HK functions.

La glucosa en conjunto con péptidos derivados de cininógenos podrían actuar desde el aparato digestivo como bloqueadores de la acción diurética-natriurética del péptido natriurético auricular / Glucose in conjunction with peptides derived from kininogens might act from digestive tract as blockers of ANP mediated diuresis-natriuresis

This paper describes long term research efforts wich have lead: 1) to the identification of peptides present in pepsanurin, a peptidic fraction obtained by pepsin hydrolisis of plasma globulins that inhibits the renal excretory action of atrial natriuretic peptide (ANP) and 2) to the discovery of an unexpected role of glucose, as a requisite, for these inhibitory effects. The active peptides identified in pepsanurin are derived from plasma kininogens, substrates of the kallikrein-kinin system. Pro-kinins of 15, 16 and 18 aminoacids, and bradykinin itself, block ANP-induced diuresis and natriuresis when injected iv, ip or into, the duodenal lumen of anesthetized rats in picomol doses. Furthermore, a novel 20 aminoacids fragment derived from kininogen dominium-1, named PU-D1, is the most potent and longer lasting blocker of ANP renal effects. The anti-ANP effects of those peptides are prevented by B2- kinin receptor antagonists. The inhibition of ANP by kinins and PU-D1 was evident only in rats infused with isotonic glucose; whereas the excretory effect of ANP was not affected in fasted rats not infused, or infused with saline. These findings provide evidence that glucose facilitates liquid retention through a kinin-mediated inhibition of ANP excretory action that may be related to the prandial cycle

Kinins mediate the inhibition of atrial natriuretic peptide diuretic effect induced by pepsanurin

Pepsanurin is a peptidic fraction resulting from pepsin digestion of plasma globulins, that inhibits ANP renal excretory actions. We studied whether kinin-like peptides mediate the anti-ANP effect by testing if pepsanurin: 1) was blocked by the kinin B12 receptor antagonist HOE-140, 2) was produced from kininogen, and 3) was mimicked by bradykinin. Anti-ANP activity was assessed in anesthetized female rats by comparing the excretory response to two ANP boluses (0.5 mug iv) given before and after ip injection of test samples. Pepsanurin from human or rat plasma (1-5 mL/Kg), and bradykinin (5-20 mug/Kg), dose-relatedly inhibited ANP-induced water, sodium, potassium and cyclic GMP urinary excretion, without affecting arterial blood pressure. The same effect was exerted by pepsin hydrolysates of purified kininogen, whereas hydrolysates of kininogen-free plasma had no effect. HOE-140 (5 mug, iv) did not alter baseline, or ANP-induced excretion, but blocked the anti-ANP effects of pepsanurin. Histamine (15 mug/Kg) plus seroalbumin hydrolysates did not affect ANP response, despite inducing larger peritoneal fluid accumulation as compared with pepsanurin or bradykinin. We concluded that kinins cleaved from kininogen mediate the anti-ANP effects of pepsanurin by activation of kinin B2 receptors, independently of changes in systemic arterial pressure or peritoneal fluid sequestration.

Effect of Leukotriene C4 on Glandular Kallikrein Activity in Bronchial Wash of Guinea Pig / 대한마취과학회지

The involvement of plasma kallikrein-kinin system in some pathological states such as bronchial asthma and coughing induced by captopril has been suggested, LTC, and LTD, have been well reported to have a potent activity of bronchoconstriction and mucous secretion. The author tried to confirm whether leukotrienes increase glandular kallikrein activity in bronchial wash or not, and if it is true, to investigate the possible mechanism of leukotrienes-induced increase of glandular kallikrein activity. Bronchial wash was collected from excised lungs of guinea pig, and incubated with synthetic substrate (Pro-Phe-Arg-MCA), and released amount of AMC was measured by fluorescence spectrophotometer as the amidase activity (glandular kallikrein activity). In order to confirm that glandular kallikrein can release kinin, bronchial wash was also incubated with purified LMW- kininogen in the presence of kininase inhibitor (o-phenanthroline), and the amount of kinin was measured by enzyme immunoassay as the kinin releasing activity of glandular kallikrein. The results were as follows: 1) The glandular kallikrein activity (control: 2.98 x 10(-11) mole/min/ml wash) was increased by pilocarpine (12-120 umole/kg, i.v.), and the increased glandular kallikrein activity by pilocarpine (41 nmole/kg, i.v.) was inhibited by atropine (4-43 nmole/kg, i.v.). 2) LTC(4) (1-10 nmole/kg, i.v.) or LTD(4) (1-10 nmole/kg, i.v.) increased the glandular kallikrein activity, but the potency of LTD, was about 1/3 of that of LTC,. The increased glandular kallikrein activity by LTC, (3 nmole/kg, i.v.) was inhibited by ONO-1078 (20-203 nmole/kg, i.p.). 3) The increased glandular kallikrein activity by LTC, (3nmole/kg, i.v.) was inhibited by in- domethacin (8-83 nmole/kg, i.p.), OKY-046 (11-113 nmole/kg, i.v.), atropine (4-43 nmole/kg, i.v.), scopolamine (9-88 umole/kg, i.v.) and Thi-D-Phe-BK (100-1000 nmole/kg, i.v.). 4) STA, (6-60pmole/kg, i.v.) increased the glandular kallikrein activity, and the increased glandular kallikrein activity by STA, (20 pmole/kg, i.v.) was inhibited by atropine (14 umole/kg, i.v.) (p < 0. 001). 5) The increased glandular kallikrein activity by pilocarpine (41 urnole/kg, i.v.) was not inhibited by indomethacin (83 umole/kg, i.p.), but it was inhibited by Thi-D-Phe-BK (300 nmole/kg, i.v.) (p< 0. 001). 6) Bradykinin (3-30 nmole/kg, i.v.) increased the glandular kallikrein activity, and the increased glandular kallikrein activity by bradykinin (30 nmole/kg, i.v.) was inhibited by indomethacin (83 umole/kg, i.p.) or atropine (14 umole/kg, i.v.) (p<0.001). 7) The kinin releasing activity by glandular kallikrein in bronchial wash was 24 x 10 " mole/min/ ml wash in control group, and it was markedly increased in pilocarpine-pretreated group (124 x 10 mole/min/ml wash) (p<0.05), and in LTC4-pretreated group (164x10 mole/min/ml wash) (p<0. 01). The increased kinin releasing activity by LTC, (3 nmole/kg, i.v.) was completely inhibited by aprotinin (5000IU/ml, i.v.). I could conclude that i ) LTC, and LTD, increased glandular kallikrein activity in bronchial wash of guinea pig, ii) the most possible mechanism of LTC,-induced increase of glandular kallikrein activity in bronchial wash may be as follows; LTC,TXA,aeetyleholineinerease of glandular kallikrein acitivity, and iii) kinin released by glandular kallikrein may enhance the action of TXA, or acetylcholine to increase the glandular kallikrein activity.

A Bothrops jararaca plasma cysteine proteinase inhibitor related to Mammalian kininogen

A kininogen-like protein was purified from Bothrops jararaca plasma by DEAE-Sephadex ion-exchange and carboxy-methul-papain-Sepharose affinity chromatography. The molecular weight, estimated by SDS-gel electrophoresis, is about 100,000 and a species of about 75,000 is formed after incubation with hosrse urinary kallikrein. After incubation with rrypsin, only traces of biological activity were detected in tests on guinea pig ileum. The purified protein inhibits papain and bromelain, does not correct the clotting time of a kininogen-depleted human plasma, and does not affect the clotting time ogf plasma from Waglerophis merremii, a nonpoisonous snake; the same type of inhibitor was foind in this nonpoisonous snake. The dissociation cosntant (Ki) for the papain-inhibitor complex is approximately 1.6 nM

High molecular weight kininogen [MHWK] in patients with schistosomal hepatic fibrosis

Plasma level of high molecular weight kininogen [HMWK] was measured in 11 patients with schistosomal hepatic fibrosis and 12 healthy control subjects using clotting assay. Prothrombin time [PT], partial thromboplastin time [PTT], alanine transaminase [ALT], serum aspartate transaminase [AST], and estimation of total serum proteins and serum albumin were also performed. HMWK was decreased in patients with schistosomal hepatic fibrosis. No significant correlation was found between HMWK, PT, PTT and other liver function tests. The decrease in HMWK suggest impairment of the hepatic synthetic function in schistosomal hepatic fibrosis