Inhibition potential of glimepiride (gli) towards important UDP-glucuronosyltransferase (UGT) isoforms in human liver.

The aim of the present study was to investigate the inhibitory potential of glimepiride towards important UDP-glucuronosyltransferase (UGT) isoforms in human liver, which play a key role in the elimination of drugs. The recombinant UGT enzymes were used as enzyme source, and a nonspecific substrate 4-methylumbelliferone (4-MU) was utilized as substrate. The results showed that 100 microM of glimepiride inhibited UGT1A1, UGT1A3, UGT1A6, UGT1A9, UGT2B7 and UGT2B15 by 54.7%, 43.1%, 100%, 70.5%, 32.7 and 37.2%, respectively. Given that glimepiride exhibited strong inhibition towards UGT1A6, further inhibitory kinetic behaviour was determined. Glimepiride exerted concentration-dependent inhibition towards UGT1A6. Both Dixon and Lineweaver-Burk plots demonstrated that inhibition of UGT1A6 was best fit for noncompetitive inhibition type, and the inhibition kinetic parameter (Ki) was calculated to be 59.8 microM. Given that UGT1A6 plays a key role in detoxification of many drugs, more attention should be given when glimepiride was co-administered with the drugs mainly undergoing UGT1A6-mediated metabolism.

Unbalanced MMP/TIMP-1 expression during the development of experimental pulmonary fibrosis with acute paraquat poisoning.

Paraquat (PQ)-induced pulmonary toxicity is known to result in pulmonary edema, infiltration of inflammatory cells and damage to the alveolar epithelium, which may progress to severe fibrosis. Matrix metalloproteinases (MMPs) and their physiological inhibitors, tissue inhibitors of matrix metalloproteinases (TIMPs), which degrade and remodel the excess extracellular matrix, are believed to play an important role in the development of fibrotic tissue. In this study, we examined the sequential expression of MMP-2, MMP-9 and TIMP-1 in a rat model of pulmonary fibrosis induced by PQ. Adult male Sprague-Dawley rats were treated intraperitoneally with PQ (20 mg/kg) and saline (control group). Rats were sacrificed at days 1, 3, 7 and 21 after the PQ treatment. Lungs were excised for histological evaluation and immunohistochemical analyses, as well as the determination of collagen content, gene expression by fluorimeter-based quantitive RT-PCR assay and gelatinolytic activity by zymography. Lung MMP-2 and -9 mRNA expression progressively increased and reached a peak on day 7 after PQ treatment, while TIMP-1 mRNA levels in the PQ-treated lungs reached a peak on day 21 after modeling. Lung zymography revealed an increase in progelatinase B, progelatinase A and their active forms. In conclusion, unbalanced MMP/TIMP-1 expression and excessive gelatinolytic activity contribute to PQ-induced pulmonary fibrosis. Their precise role should be studied in depth as they may represent relevant therapeutic targets for PQ poisoning-induced pulmonary fibrosis.

[Association of urinary albumin excretion rate and hyperuricemia with macrovascular atherosclerosis in type 2 diabetic patients].

OBJECTIVE: To investigate the association of urinary albumin excretion rate (UAER) and hyperuricemia with macrovascular atherosclerosis in type 2 diabetic patients. METHODS: Ninety-seven type 2 diabetic patients were divided into two groups according to the UAER, namely group A with UAER between 20 and 200 microg/min (n=63) and group B with UAER > or = 200 microg/min (n=34); the patients were also classified into hyperuricemia group (group C, n=59) and normal blood uric acid (BUA) group (group D, n=38). The disease course, BUA, fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoproteins (HDL), UAER and arteria carotis intima-media thickness (IMT) were determined in these patients. The relationship of UAER and hyperuricemia with carotid arterial IMT was analyzed statistically. RESULTS: The levels of TG, TC, LDL and HDL showed no significant differences between the 4 groups (P>0.05). The disease course, BUA, UAER, and FBG levels and IMT in groups A and C were significantly higher than those in groups C and D (P<0.05), but no such differences were found between groups A and C or between groups B and D (P>0.05). Arotid arterial IMT was independently correlated to the disease course, BUA and UAER (r=0.201, 0.1999, 0.211, respectively, P<0.05), and a significant positive correlation was noted between BUA and UAER (r=0.221, P<0.05). CONCLUSION: Macrovascular atherosclerosis in type 2 diabetic patients is significantly correlated to the disease course, BUA and UAER levels, which can be used to evaluate and predict macrovascular atherosclerosis in type 2 diabetic patients.

[Cloning and sequence analysis of variable region gene of anti-idiotype monoclonal antibody against Vibrio alginolyticus].

AIM: To clone and sequence V(H) and V(L) genes of anti-idiotype monoclonal antibody (mAb) against vibrio alginolyticus. METHODS: Total RNA was extracted from hybridoma cell AL1 secreting mAb against vibrio alginolyticus and cDNA was amplified by RT-PCR. Then the cDNA was inserted into PMD18-T vector and its sequence was analyzed. RESULTS: The V(H) gene contained 369 bp and encoded 123 amino acid residues; the V(L) gene contained 339 bp and encoded 113 amino acid residues. There were four FRs, three CDRs and two characteristic cysteine residues in the V(H) and V(L) genes, respectively. CONCLUSION: The successful cloning of the V(H) and V(L) genes of anti-idiotype mAb against vibrio alginolyticus provides a sound basis for construction of gene-engineering vaccine of the anti-idiotype mAb against vibrio alginolyticus.