Sputum-to-serum hydrogen sulphide ratio as a novel biomarker of predicting future risks of asthma exacerbation.

BACKGROUND: Increased level of hydrogen sulphide (H2 S) in sputum is reported to be a new biomarker of neutrophilic airway inflammation in chronic airway disorders. However, the relationship between H2 S and disease activity remains unclear. OBJECTIVE: We investigated whether H2 S levels could vary during different conditions in asthma. METHOD: H2 S levels in sputum and serum were measured using a sulphide-sensitive electrode in 47 stable asthmatic subjects (S-BA), 21 uncontrolled asthmatic subjects (UC-BA), 26 asthmatic subjects with acute exacerbation (AE-BA) and 15 healthy subjects. Of these, H2 S levels during stable, as well as exacerbation states, were obtained in 13 asthmatic subjects. RESULTS: Sputum H2 S levels were significantly higher in the AE-BA subjects compared to the UC-BA and healthy subjects (P < .05). However, serum H2 S levels in the AE-BA subjects were lower than in the S-BA subjects (P < .001) and similar to those in healthy subjects. Thus, the sputum-to-serum ratio of H2 S (H2 S ratio) in the AE-BA subjects was significantly higher than in the S-BA, UC-BA and healthy subjects (P < .05). Among all subjects, sputum H2 S levels showed a trend to decrease with FEV1 %predicted and significantly positive correlations with sputum neutrophils (%), sputum IL-8 and serum IL-8. A multiple linear regression analysis showed that sputum H2 S was independently associated with increased sputum neutrophils (%) and decreased FEV1 %predicted (P < .05). The cut-off level of H2 S ratio to indicate an exacerbation was ≥0.34 (area under the curve; 0.88, with a sensitivity of 81.8% and specificity of 72.7%, P < .001). Furthermore, half of the asthmatic subjects with H2 S ratios higher than the cut-off level experienced asthma exacerbations over the following 3 months after enrolment. CONCLUSIONS: The H2 S ratio may provide useful information on predicting future risks of asthma exacerbation, as well as on obstructive neutrophilic airway inflammation as one of the non-Th2 biomarkers, in asthma.

N-linked glycosylation of mouse adiponectin.

Adiponectin is an insulin-sensitizing adipokine with antidiabetic, anti-atherogenic, anti-inflammatory, and cardioprotective properties. Previously, some types of posttranslational modification on adiponectin have been reported. In this study, we demonstrate that mouse adiponectin protein migrated as 2 bands on SDS-PAGE gel. Slower migrating band of adiponectin was reduced by PNGase treatment. PNGase is known as N-glycosidase, and is able to change the mobility of N-glycosylated protein on SDS-PAGE gel. This result indicates the possibility that slower band shifted and overlapped with faster band by cleavage of N-glycan. To further clarify the N-glycosylation of adiponectin, we investigated the effect of N-glycosylation inhibitor tunicamycin on 3T3-L1 adipocytes. Tunicamycin significantly reduced the ratio of slower band to faster band in culture medium from 3T3-L1 adipocytes. This result also indicates the possibility that slower band of adiponectin is N-glycosylated. Lastly, to identify glycosylated asparagine residues, we established 3T3-L1 cell lines stably expressing wild type and mutant adiponectin in N-glycosylation sites. Wild-type adiponectin protein migrated as double bands, and mutant adiponectin in either asparagine at position 53 or threonine at 55 lacked slower band. These results suggest that a part of mouse adiponectin is modified by N-linked glycosylation at asparagine 53.

Measurement of adiponectin production from differentiated metabolic stem cells.

To treat metabolic syndrome, fat tissue dysfunction should be corrected rather than controlling conventional risk factors such as hypertension, dyslipidemia, and diabetes mellitus. For this purpose, accumulating evidence suggests increasing plasma adiponectin levels can be a key treatment strategy, especially in setting of food or drug selection. Here we report that adipocyte precursors obtained from several sites of fat tissue, which we call Metabolic Stem Cells (MSC), could be used as a novel screening system to identify adiponectin enhancing drugs or food for individual patients. MSC were prepared from fat tissues collected from 29 patients. They were differentiated in cultures into mature adipocytes. The time course of adiponectin production was independent of the number of mature adipocytes and gradually decreased at 48 h after differentiation. Pioglitazone, a full PPARgamma agonist, stabilized adiponectin production at days 8-16 after differentiation, whereas telmisartan, a partial PPARgamma agonist, showed variable response. Dividing the adiponectin secretion of day 12 by that of day 10 provided an estimate of adiponectin-producing activity irrespective of the number of MSC-derived adipocytes in culture. Using this score of adiponectin-production activity, we successfully assessed 16 agents in a 96-well plate. The effect of each agent on adiponectin production showed a similar pattern, independent of the site of isolated adipose tissue. Our results show that MSC can be used as a tool for selecting drugs that enhance adiponectin-production activity.

Adiponectin plays a protective role in caerulein-induced acute pancreatitis in mice fed a high-fat diet.

BACKGROUND: Obesity is a risk factor for acute pancreatitis (AP), but the molecular mechanism remains unclear. Adiponectin, an adipose tissue-derived secretory factor, has anti-inflammatory properties in addition to various biological functions, and its plasma concentrations are reduced in obese subjects. However, the role of adiponectin in AP has not been investigated. AIM: To determine the effects of adiponectin on AP. METHODS: We investigated the effects of adiponectin on experimental AP by using adiponectin-knockout (APN-KO) mice and adenovirus-mediated adiponectin over-expression. AP was induced by 10 hourly intraperitoneal injections of low-dose caerulein (10 microg/kg) after 2 week feeding of normal chow or a high-fat diet (HFD) in wild-type (WT) and APN-KO mice. We evaluated the severity of AP biochemically and morphologically. RESULTS: Low-dose caerulein treatment did not induce pancreatic damage in either WT or APN-KO mice under normal chow feeding. APN-KO mice, but not WT mice, fed a HFD and then treated with caerulein developed pancreatic damage and inflammation, accompanied by increased macrophage/neutrophil infiltration and upregulation of pro-inflammatory mediators such as tumour necrosis factor alpha in the pancreas. Adenovirus-mediated over-expression of adiponectin attenuated the severity of HFD/caerulein-induced AP in APN-KO mice. CONCLUSIONS: Adiponectin plays a protective role in caerulein-induced AP in HFD-fed mice.

Involvement of an SHP-2-Rho small G protein pathway in hepatocyte growth factor/scatter factor-induced cell scattering.

Hepatocyte growth factor/scatter factor (HGF/SF) induces cell scattering through the tyrosine kinase-type HGF/SF receptor c-Met. We have previously shown that Rho small G protein (Rho) is involved in the HGF/SF-induced scattering of Madin-Darby canine kidney (MDCK) cells by regulating at least the assembly and disassembly of stress fibers and focal adhesions, but it remains unknown how c-Met regulates Rho activity. We have found here a novel signaling pathway of c-Met consisting of SHP-2-Rho that regulates the assembly and disassembly of stress fibers and focal adhesions in MDCK cells. SHP-2 is a protein-tyrosine phosphatase that contains src homology-2 domains. Expression of a dominant negative mutant of SHP-2 (SHP-2-C/S) markedly increased the formation of stress fibers and focal adhesions in MDCK cells and inhibited their scattering. C3, a Clostridium botulinum ADP-ribosyltransferase, and Y-27632, a specific inhibitor for ROCK, reversed the stimulatory effect of SHP-2-C/S on stress fiber formation and the inhibitory effect on cell scattering. Vav2 is a GDP/GTP exchange protein for Rho. Expression of a dominant negative mutant of Vav2 blocked the stimulatory effect of SHP-2-C/S on stress fiber formation. Conversely, expression of mutants of Vav2 that increased stress fiber formation inhibited HGF/SF-induced cell scattering. These results indicate that SHP-2 physiologically modulates the activity of Rho to form stress fibers and focal adhesions and thereby regulates HGF/SF-induced cell scattering. In addition, Vav2 may be involved in the SHP-2-Rho pathway.

Interactive binding to the two principal ligand binding sites of human serum albumin: effect of the neutral-to-base transition.

The relationship between the two principal ligand binding sites, sites I and II, on human serum albumin (HSA) was quantitatively and qualitatively examined by equilibrium dialysis and fluorescence spectroscopy. Among the three subsite markers to site I, only the binding of dansyl-L-asparagine (DNSA), which is a subsite Ib marker (K. Yamasaki et al., Biochim. Biophys. Acta 1295 (1996) 147), was inhibited by the simultaneous binding of a site II ligand, such as ibuprofen and diazepam. This indicates that, in contrast to subsite Ib, subsites Ia and Ic do not strongly interact with site II. The thermodynamic characteristics for the coupling reaction between DNSA and ibuprofen and between DNSA and diazepam, which gave positive coupling free energies and negative values for both coupling enthalpy and entropy, indicated that the reaction process was entropically driven. Increase of pH from 6.5 to 8.2 caused an increase in coupling constant and entropy for the mutual antagonism between DNSA and the site II ligands on binding to HSA. The site II ligand-induced red-shift of lambda(max) and solvent accessibility of DNSA in subsite Ib were decreased when the albumin molecule was isomerized from the neutral (N) to the base (B) conformation in the physiological pH region. Based on these findings, we conclude that a 'competitive' like strong allosteric regulation exists for the binding of these two ligands to the N conformer, whereas for the B conformer this interaction can be classified as nearly 'independent'. Since the distance between Trp-214, which resides within the site I subdomain, and Tyr-411, which is involved in site II, is increased by 6 A during the N-B transition (N.G. Hagag et al., Fed. Proc. 41 (1982) 1189), we propose a mechanism for the pH-dependent antagonistic binding between subsite Ib and site II, which involves the transmission of ligand-induced allosteric effects from one site to another site, modified by changes in the spatial relationship of sites I and II caused by the N-B transition.

Impact of cilostazol on restenosis after percutaneous coronary balloon angioplasty.

BACKGROUND: Restenosis after percutaneous transluminal coronary (balloon) angioplasty (PTCA) remains a major drawback of the procedure. We previously reported that cilostazol, a platelet aggregation inhibitor, inhibited intimal proliferation after directional coronary atherectomy and reduced the restenosis rate in humans. The present study aimed to determine the effect of cilostazol on restenosis after PTCA. METHODS AND RESULTS: Two hundred eleven patients with 273 lesions who underwent successful PTCA were randomly assigned to the cilostazol (200 mg/d) group or the aspirin (250 mg/d) control group. Administration of cilostazol was initiated immediately after PTCA and continued for 3 months of follow-up. Quantitative coronary angiography was performed before PTCA and after PTCA and at follow-up. Reference diameter, minimal lumen diameter, and percent diameter stenosis (DS) were measured by quantitative coronary angiography. Angiographic restenosis was defined as DS at follow-up >50%. Eligible follow-up angiography was performed in 94 patients with 123 lesions in the cilostazol group and in 99 patients with 129 lesions in the control group. The baseline characteristics and results of PTCA showed no significant difference between the 2 groups. However, minimal lumen diameter at follow-up was significantly larger (1.65+/-0.55 vs 1.37+/-0.58 mm; P<0.0001) and DS was significantly lower (34.1+/-17.8% vs 45.6+/-19. 3%; P<0.0001) in the cilostazol group. Restenosis and target lesion revascularization rates were also significantly lower in the cilostazol group (17.9% vs 39.5%; P<0.001 and 11.4% vs 28.7%; P<0. 001). CONCLUSIONS: Cilostazol significantly reduces restenosis and target lesion revascularization rates after successful PTCA.

Improving the pharmacokinetic and pharmacodynamic properties of a drug by chemical conversion to a chimera drug.

The purpose of the present study is to investigate a new concept which involves the conjugation of two drugs having different pharmacological activities which is termed a 'chimera drug (mutual prodrug)', in drug delivery optimization using a chemical modification approach. The conjugates of FP, an NSAID, with histamine H(2) antagonists were synthesized, in order to investigate the reduction in gastric damage by NSAID, and their pharmaceutical, pharmacokinetic and pharmacological properties were examined. The limited data obtained herein indicate that the chimera drug composed of FP and PPA was effective in reducing gastric damage by FP, with no changes in its biopharmaceutical properties, compared with the conventional prodrugs such as ester-type prodrugs.

Therapeutic keratoplasty using preserved corneas from keratoconus eyes.

PURPOSE: To report and discuss cases of lamellar keratoplasty using corneas obtained during previous penetrating keratoplasty in keratoconus eyes. METHODS: Corneal buttons were obtained from 7 keratoconus patients and stored in a preserving solution for 7-60 days (average, 32.4 days) before use. The recipient eyes comprised recurrent pterygium 3 eyes, primary pterygium 1 eye, pseudopterygium 1 eye, corneal perforation with iris prolapse due to fungal corneal ulcer 1 eye, and limbal dermoid 1 eye. RESULTS: The recipient eyes ran favorable courses in general. Graft rejection developed in 2 eyes and was successfully treated with topical and systemic corticosteroid. CONCLUSIONS: Preserved corneas from keratoconus eyes were found useful in therapeutic lamellar keratoplasty. By this procedure, the current inadequate supply of donor corneas in eye banks in Japan can be augmented.

[Therapeutic keratoplasty using corneas obtained from keratoconus patients].

Therapeutic lamellar keratoplasty was performed using corneas obtained from keratoconus patients undergoing penetrating keratoplasty. The corneas used in this series were stored in preservation solution for 7 to 59 days (average, 27.8 days) and submitted to surgery. The recipients were three patients with recurrent pterygium, one with primary pterygium, one with corneal perforation and iris prolapse due to fungal corneal ulcer, and one with limbal dermoid. Graft rejection developed in two cases postoperatively, but they were successfully treated with steroid therapy. During the entire period of clinical observation, there was no sign of recurrence of pterygium. In the case of the fungal corneal ulcer, the site of perforation healed quickly and the donor cornea maintained its transparency. A marked cosmetic improvement was achieved in the case of the limbal dermoid. Obtaining corneas from keratoconus patients and storing them for a short period is a potentially useful application for therapeutic lamellar keratoplasty.

[Fundamental and clinical studies of a sustained release preparation of cefaclor in the surgical field].

Fundamental and clinical studies of S6472 (sustained release preparation of cefaclor (CCL] were conducted in the surgical field and it was confirmed that the preparation is a useful drug. The following is the summary of the results from the fundamental and clinical studies: In vitro antibacterial activity. CCL showed MICs of 0.78 to 6.25 micrograms/ml against almost strains of S. aureus, E. coli and Klebsiella isolated from surgical wound regions, and the antibacterial activities were stronger than those of cephalexin (CEX). Clinical efficacy. S6472 was orally administered to 33 patients with skin and soft tissue infections in 2 divided doses. As a result, excellent clinical response was observed in 13 patients, good response observed in 14 patients, fair in 4 and poor in 1. The clinical efficacy in 1 of the 33 patients was unknown. Overall clinical effective rate was 84.4%. Adverse reaction. In 2 patients, mild gastrointestinal symptoms were observed.

Stereoselective disposition of flurbiprofen from a mutual prodrug with a histamine H2-antagonist to reduce gastrointestinal lesions in the rat.

The in vitro and in vivo stereoselective hydrolysis characteristics of the mutual prodrug FP-PPA, which is a conjugate of flurbiprofen (FP) with the histamine H2-antagonist PPA, to reduce gastrointestinal lesions induced by FP were investigated and compared with those of FP methyl ester (rac-FP-Me) and FP ethyleneglycol ester (rac-FP-EG). The rac-FP derivatives were hydrolyzed preferentially to the (+)-S-isomer in plasma and to the (-)-R-isomer in liver and small intestinal mucosa. Interestingly, in the gastric mucosa, the stereoselectivity of hydrolysis of (-)-R-FP-PPA was opposite from that of rac-FP-Me and rac-FP-EG, which suggested that the stereoselective hydrolysis of FP-PPA was helpful in reducing gastric damage induced by (+)-S-FP. However, hydrolysis of all rac-FP derivatives was found to be catalyzed by carboxylesterases in the gastric mucosa. The stereoselective disposition of FP enantiomers early after intravenous administration of rac-FP-PPA could be explained by the stereoselective formation of (-)-R-FP from rac-FP-PPA in the liver. (-)-R-FP-PPA was completely hydrolyzed to form (-)-R-FP in vivo, while 78% of (+)-S-FP-PPA was hydrolyzed to (+)-S-FP, with a corresponding decrease in the area under the curve. Twenty-five percent of (+)-S-FP-PPA might be eliminated as the intact prodrug or its metabolites other than FP. The most important bioconversion of FP-PPA occurred in plasma, and additional hydrolysis of the R-enantiomer in liver resulted in the stereoselectivity observed following both i.v. and p.o. administration.