Publications by authors named "Mengfei Zheng"

6-Diazo-5-oxo-L-norleucine (DON) is a potent glutamine antagonist with toxic side effects; in order to reduce these effects, multiple prodrugs have been designed. However, there are currently no reports of a DON prodrug with a defined mechanism to achieve high tumor selectivity. To improve the selective toxicity of DON to tumor cells while reducing systemic toxicity, a hypoxia-activated prodrug, termed HDON, was designed.

View Article and Find Full Text PDF

Antibody-drug conjugates (ADCs) have exciting possibilities in targeted tumor therapy. However, in the existing ADC preparation processes, the random attachment of the payloads to the antigen-binding fragments (Fab) greatly increases the risk of disrupting its antigen recognition ability, while the drug-antibody ratio (DAR) is low, leading to a cumbersome preparation process and low drug delivery efficiency. Herein, poly(glutamic acid) is used to expand the number of drug binding sites, based on the "click chemistry" of azide and DBCO, and the high affinity of Fc-III-4C peptide to the crystalline fragment (Fc) of the monoclonal antibodies.

View Article and Find Full Text PDF

Resiquimod (R848) is an immunomodulator that causes a severe systemic inflammatory reaction due to low tumor selectivity, thus hindering its use in cancer therapy. Therefore, an azide-masked prodrug (R848-N ) of R848 is developed, which is selectively activated to R848 in hypoxic tumors. R848-N significantly reduces pro-inflammatory cytokines in treated mice to 1/12 compared to R848 at the same dose.

View Article and Find Full Text PDF

Mitochondrial reactive oxygen species (ROS)generation plays an essential role in the process of adipocyte differentiation and is involved in the development of obesity and associated metabolic diseases. Various dietary flavonoids possess the substantial anti-adipogenic activity. However, it is unclear whether these flavonoids inhibit adipocyte differentiation by reducing ROS generation.

View Article and Find Full Text PDF

Natural polymers like polysaccharides, polypeptides and their derivatives are broadly applied in drug delivery due to excellent biocompatibility and biodegradability. In this study, the dissolving tablets, formed with carboxymethylcellulose/poly-l-lysine/tripolyphosphate (CMC/PLL/TPP) complex, were prepared using metformin hydrochloride (MetHCl) as model drug. Confocal laser scanning microscopy observation manifested that FITC-labeled PLL interacted with CMC and formed a uniform interior microstructure.

View Article and Find Full Text PDF

Two new 30-noroleanane triterpenes, 2α,3β,20α-trihydroxy-30-norolean-12-en-28-oic acid (1), 2α,3β-dihydroxy-23-oxo-30-norolean-12,20(29)-dien-28-oic acid (2), were isolated from the pericarps of Akebia trifoliata, together with four known ones, 3β-akebonoic acid (3), 2α,3β-dihydroxy-30-noroleana-12,20(29)-dien-28-oic acid (4), 3α-akebonoic acid (5) and quinatic acid (6). Their structures were established on the basis of detailed spectroscopic analysis, and they were all isolated from the pericarps of A. trifoliata for the first time.

View Article and Find Full Text PDF

A novel quinic acid derivative, 5-O-trans-o-coumaroylquinic acid methyl ester (1), together with three known ones, chlorogenic acid methyl ester (2), macranthoin F (3) and macranthoin G (4), were isolated from the aerial parts of the invasive plant Ageratina adenophora (Spreng.). The structure of new compound 1 was elucidated on the basis of extensive spectroscopic analysis, including 1D- and 2D-NMR techniques.

View Article and Find Full Text PDF