[Arctigenin mitigates vascular endothelial injury in rats with pregnancy-induced hypertension via autophagy-NLRP3 inflammasome pathway].

This study aims to investigate the effect and mechanism of arctigenin(ARC) in the treatment of vascular endothelial injury in rats with pregnancy-induced hypertension(PIH). Fifty SD rats pregnant for 12 days were randomly assigned into a control group, a model group, an ARC group, a rapamycin(RAP, autophagy inducer) group, and an ARC+3-methyladenine(3-MA, autophagy inhibitor) group, with 10 rats in each group. The rats in the other groups except the control group were intraperitoneally injected with nitrosyl-L-arginine methyl ester(50 mg·kg~(-1)·d~(-1)) to establish the PIH model on the 13th day of pregnancy.

Neuronal growth-inhibitory factor (metallothionein-3): structure-function relationships.

Neuronal growth-inhibitory factor (GIF), also named metallothionein-3, inhibits the outgrowth of neuronal cells. Recent studies on the structure of human GIF, carried out using NMR and molecular dynamics simulation techniques, have been summarized. By studying a series of protein-engineered mutants of GIF, we showed that the bioactivity of GIF is modulated by multiple factors, including the unique TCPCP motif-induced characteristic conformation, the solvent accessibility and dynamics of the metal-thiolate cluster, and the domain-domain interactions.

The role of Ile476 in the structural stability and substrate binding of human cytochrome P450 2C8.

The biological function and stability of a cytochrome P450 (CYP) mainly depend on the subtle properties of the residues in the active site cavity, which are generally more divergent among proteins than other parts of the protein. As the most unique member of human CYP2C family, CYP2C8 has an isoleucine (Ile) 476 instead of phenylalanine (Phe) in substrate recognizing site 6 (SRS6). However, the role of Ile476 of CYP2C8 is still unknown.

The structural and biological significance of the EAAEAE insert in the alpha-domain of human neuronal growth inhibitory factor.

Human neuronal growth inhibitory factor (hGIF) is able to inhibit the outgrowth of neurons. As compared with the amino acid sequences of metallothionein 1/2, hGIF contains two insertions: a Thr at position 5 and an acidic hexapeptide EAAEAE(55-60) close to the C-terminus. Moreover, all mammalian growth inhibitory factor sequences contain a conserved CPCP(6-9) motif.

Important roles of the conserved linker-KKS in human neuronal growth inhibitory factor.

Metallothinein-3 (MT3), also named neuronal growth inhibitory factor (GIF), is attractive by its distinct neuronal growth inhibitory activity, which is not shared by other MT isoforms. The polypeptide chain of GIF is folded into two individual domains, which are connected by a highly conserved linker, KKS. In order to figure out the significance of the conserved segment, we constructed several mutants of human GIF (hGIF), including the K31/32A mutant, the K31/32E mutant and the KKS-SP mutant by site-directed mutagenesis.

Study on structure-property-reactivity-function relationship of human neuronal growth inhibitory factor (hGIF).

Human metallothionein-3 (hMT3), also named as human neuronal growth inhibitory factor (hGIF), can inhibit the outgrowth of embryonic cortical neurons in the presence of brain extracts. In order to systematically study the structure-property-reactivity-function relationship of hGIF, our laboratory designed a series of mutants and studied their structure, property, reactivity and functions by a series of chemical and biological tools including UV spectroscopy, CD spectroscopy, NMR, chemical reaction and primary neuronal culture assays. In summary, we concluded that the bioactivity of hGIF was regulated by multiple factors, including the (6)CPCP(9) motif, an additional threonine insert at sequence position 5, domain-domain interactions, the structure and stability of the metal-thiolate cluster and the linker.

Incorporation of a glycine within the conserved TCPCP motif of human neuronal growth inhibitory factor significantly reduces its bioactivity.

It has been reported that the (6)CPCP(9) motif near the N-terminus is pivotal to the inhibitory activity of human neuronal growth inhibitory factor (hGIF). In order to better understand the biological significance of this region on the structure, property and function of hGIF, we introduced a highly flexible residue, Gly, either in front of the (6)CPCP(9) motif (the IG6 mutant, TGCPCP) or in the middle of it (the IG8 mutant, TCPGCP) and investigated their structural and metal binding properties in detail. The results showed that the overall structure and the stability of the metal-thiolate clusters of the two mutants were comparable to that of hGIF.

Forced unfolding of apocytochrome b5 by steered molecular dynamics simulation.

Apocytochrome b5 (apocyt b5), a small b-type cytochrome with heme prosthetic group removal, has been subjected to steered molecular dynamics (SMD) simulations for investigating the consequences of mechanical force-induced unfolding. Both constant velocity (0.5 and 1.

Structural prediction of the beta-domain of metallothionein-3 by molecular dynamics simulation.

The beta-domain of metallothionein-3 (MT3) has been reported to be crucial to the neuron growth inhibitory bioactivity. Little detailed three-dimensional structural information is available to present a reliable basis for elucidation on structure-property-function relationships of this unique protein by experimental techniques. So, molecular dynamics simulation is adopted to study the structure of beta-domain of MT3.