Aim： To access beta-endorphin levels in serum as well as seminal plasma in different infertile male groups. Methods： Beta-endorphin was estimated in the serum and seminal plasma by enzyme-linked immunosorbent assay ...Aim： To access beta-endorphin levels in serum as well as seminal plasma in different infertile male groups. Methods： Beta-endorphin was estimated in the serum and seminal plasma by enzyme-linked immunosorbent assay （ELISA） method in 80 infertile men equally divided into four groups： non-obstructive azoospermia （NOA）, obstructive azoospermia （OA）, congenital bilateral absent vas deferens （CBVAD） and asthenozoospermia. The results were compared to those of 20 normozoospermic proven fertile men. Results： There was a decrease in the mean levels of betaendorphin in the seminal plasma of all successive infertile groups （mean ± SD： NOA 51.30 ± 27.37, OA 51.88 ± 9.47, CBAVD 20.36 ± 13.39, asthenozoospermia 49.26 ± 12.49 pg/mL, respectively） compared to the normozoospermic fertile control （87.23 ± 29.55 pg/mL）. This relation was not present in mean serum level of beta-endorphin between four infertile groups （51.09 ± 14.71, 49.76 ± 12.4, 33.96 ± 7.2, 69.1 ± 16.57 pg/mL, respectively） and the fertile control group （49.26 ± 31.32 pg/mL）. The CBVAD group showed the lowest seminal plasma mean level of beta-endorphin. Testicular contribution of seminal beta-endorphin was estimated to be approximately 40%. Seminal beta-endorphin showed significant correlation with the sperm concentration （r = 0.699, P = 0.0188） and nonsignificant correlation with its serum level （r = 0.375, P = 0.185） or with the sperm motility percentage （r = 0.470, P = 0.899）. Conclusion： The estimation of beta-endorphin alone is not conclusive to evaluate male reproduction as there are many other opiates acting at the hypothalamic pituitary gonadal axis.展开更多
A series of analogs of endomorphin-2 （EM-2） with phenylglycine （Phg） in position 3 or 4 were synthesized. In electrospray ionization Fourier transform ion cyclotron resonance （ESI-Fr-ICR） MS/MS spectra of these ...A series of analogs of endomorphin-2 （EM-2） with phenylglycine （Phg） in position 3 or 4 were synthesized. In electrospray ionization Fourier transform ion cyclotron resonance （ESI-Fr-ICR） MS/MS spectra of these compounds, some b, y, a, and internal ions were observed and slight mass differences between the calculated and observed results are obtained. Their sequences were derived successfully. However, the MS/MS patterns of these analogs with Dphg and Lphg were very similar. It is hard to distinguish them by MS/MS spectra. Moreover, if the third position was substituted by phenylglycine （L or D）, a rearrangement could occur in MS/MS experiment to lose proline residue.展开更多
Directed peptides C-terminal modification enabled by the engineered biomolecular catalyst-peptide amidase 12 B has been achieved via computational protein engineering. The engineered enzyme exhibits great promising po...Directed peptides C-terminal modification enabled by the engineered biomolecular catalyst-peptide amidase 12 B has been achieved via computational protein engineering. The engineered enzyme exhibits great promising potential in the C-terminal modification of opioid peptides using prop-2-yn-1-amine(PYA) or prop-2-en-l-amine(PEA) as the nucleophile. A variety of opioid peptides could be readily functionalized at the C-terminal chain in high yield in a mild and selective manner. Notably, modified opioid peptides bearing alkynyl moiety could be further functionalized through well-established click reaction.展开更多
文摘Aim： To access beta-endorphin levels in serum as well as seminal plasma in different infertile male groups. Methods： Beta-endorphin was estimated in the serum and seminal plasma by enzyme-linked immunosorbent assay （ELISA） method in 80 infertile men equally divided into four groups： non-obstructive azoospermia （NOA）, obstructive azoospermia （OA）, congenital bilateral absent vas deferens （CBVAD） and asthenozoospermia. The results were compared to those of 20 normozoospermic proven fertile men. Results： There was a decrease in the mean levels of betaendorphin in the seminal plasma of all successive infertile groups （mean ± SD： NOA 51.30 ± 27.37, OA 51.88 ± 9.47, CBAVD 20.36 ± 13.39, asthenozoospermia 49.26 ± 12.49 pg/mL, respectively） compared to the normozoospermic fertile control （87.23 ± 29.55 pg/mL）. This relation was not present in mean serum level of beta-endorphin between four infertile groups （51.09 ± 14.71, 49.76 ± 12.4, 33.96 ± 7.2, 69.1 ± 16.57 pg/mL, respectively） and the fertile control group （49.26 ± 31.32 pg/mL）. The CBVAD group showed the lowest seminal plasma mean level of beta-endorphin. Testicular contribution of seminal beta-endorphin was estimated to be approximately 40%. Seminal beta-endorphin showed significant correlation with the sperm concentration （r = 0.699, P = 0.0188） and nonsignificant correlation with its serum level （r = 0.375, P = 0.185） or with the sperm motility percentage （r = 0.470, P = 0.899）. Conclusion： The estimation of beta-endorphin alone is not conclusive to evaluate male reproduction as there are many other opiates acting at the hypothalamic pituitary gonadal axis.
文摘A series of analogs of endomorphin-2 （EM-2） with phenylglycine （Phg） in position 3 or 4 were synthesized. In electrospray ionization Fourier transform ion cyclotron resonance （ESI-Fr-ICR） MS/MS spectra of these compounds, some b, y, a, and internal ions were observed and slight mass differences between the calculated and observed results are obtained. Their sequences were derived successfully. However, the MS/MS patterns of these analogs with Dphg and Lphg were very similar. It is hard to distinguish them by MS/MS spectra. Moreover, if the third position was substituted by phenylglycine （L or D）, a rearrangement could occur in MS/MS experiment to lose proline residue.
基金supported by the National Natural Science Foundation of China(No.31601412)the 100 Talent Program grant and Biological Resources Service Network Initiative(No.ZSYS-012)grant from the Chinese Academy of Sciences(No.SKT1604)
文摘Directed peptides C-terminal modification enabled by the engineered biomolecular catalyst-peptide amidase 12 B has been achieved via computational protein engineering. The engineered enzyme exhibits great promising potential in the C-terminal modification of opioid peptides using prop-2-yn-1-amine(PYA) or prop-2-en-l-amine(PEA) as the nucleophile. A variety of opioid peptides could be readily functionalized at the C-terminal chain in high yield in a mild and selective manner. Notably, modified opioid peptides bearing alkynyl moiety could be further functionalized through well-established click reaction.
