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Aim: To design and synthesize a series of novel amino acid-binding 1,5-diarylpyrazole derivatives, which are intended to act as prodrugs with better aqueous solubility than celecoxib, and which will exert potent anti-inflammatory activities after being converted to their parent compounds in vivo., Methods: To introduce an amino acid, celecoxib analogs containing amino or methylamino group were synthesized first through multi-step chemical reactions. All the synthesized compounds were screened in an intact cell-based assay in vitro and in carrageenan-induced mouse paw edema in vivo. Some active compounds were selected for further evaluation in a carrageenan-induced rat paw edema model. The preliminary pharmacokinetics experiments were conducted using high performance liquid chromatography/mass spectrometry (HPLC/MS)., Results: Celecoxib, 6 of the 1,5-diarylpyrazole class of celecoxib analogs, and their amino acid derivatives (hydrochloride salts) were synthesized. In vitro screening, the hydrochloride salts showed decreased inhibitory effects on cyclooxygenase (COX)-1 and COX-2 compared with their parent compounds, but some exhibited potent anti-inflammatory activity in vivo. Compound 4a was selected for further evaluation, and its anti-inflammatory effect was equivalent to that of celecoxib after oral administration in the carrageenan-induced rat paw edema model. At three doses (25 mg/kg, 50 mg/kg, and 100 mg/kg) the percentage inhibition on edema was 20.7%, 52.6%, and 62.6% (for compound 4a) and 27.8%, 38.4%, and 40.1% (for celecoxib), respectively. Preliminary pharmacokinetic evaluations support the hypothesis that compound 4a was actually converted to its parent compound, compound 4., Conclusion: The compound bound with amino acid acts like prodrug, which can exert anti-inflammatory effect similar to celecoxib after being converted to its parent compound. This finding will be of great benefit in carrying out structural modifications of prodrug-like selective COX-2 inhibitors.

Aim: To investigate molecular mechanism of testis development and spermatogenesis., Methods: A human testis cDNA microarray was hybridized with probes from human adult testis, embryo testis and human sperm, and the differential expressed clones were sequenced and analyzed. Expression of PIAS-NY gene was analyzed by RT-PCR., Result: A new isoform of PIAS family, named PIAS-NY, was isolated from human testis cDNA library. It was strongly expressed in adult testis and weakly expressed in both embryo testis and human sperm. Analysis of the open reading frame of PIAS-NY indicated that PIAS-NY was a polypeptide of 405 amino acid residues, and the sequence from the 15th amino acid to the end of PIAS-NY protein was the same as the N-terminal amino acids of PIASx-alpha and PIASx-beta protein. PIAS-NY protein contained two conserved putative LXXLL signature motifs and a zinc binding motif. Tissue distribution analysis revealed that PIAS-NY was predominantly expressed in testis, weakly in the pancreas, and almost imperceptibly in the other organs., Conclusion: PIAS-NY may play important role in testis development and/or spermatogenesis.

Aim: To clone a new gene related to human spermatogenesis., Methods: cDNA probes of embryo and adult testis were used to hybridize the cDNA microarray of adult testis, and the clones of differential hybridization were sequenced and analyzed., Results: A novel isoform of calpastatin exclusively and highly expressed in human adult testis was found., Conclusion: A novel isoform of calpastatin expresses in human testis and it is related to spermatogenesis.