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Rationale: Eucommia cortex is the core herb in traditional Chinese medicine preparations for the treatment of osteoporosis. Pinoresinol diglucoside (PDG), the quality control marker and the key pharmacodynamic component in Eucommia cortex, has attracted global attention because of its definite effects on osteoporosis. However, the in vivo metabolic characteristics of PDG and its anti‐osteoporotic mechanism are still unclear, restricting its development and application. Methods: Ultra‐high‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry was used to analyze the metabolic characteristics of PDG in rats, and its anti‐osteoporosis targets and mechanism were predicted using network pharmacology. Results: A total of 51 metabolites were identified or tentatively characterized in rats after oral administration of PDG (10 mg/kg/day), including 9 in plasma, 28 in urine, 13 in feces, 10 in liver, 4 in heart, 3 in spleen, 11 in kidneys, and 5 in lungs. Furan‐ring opening, dimethoxylation, glucuronidation, and sulfation were the main metabolic characteristics of PDG in vivo. The potential mechanism of PDG against osteoporosis was predicted using network pharmacology. PDG and its metabolites could regulate BCL2, MARK3, ALB, and IL6, involving PI3K‐Akt signaling pathway, estrogen signaling pathway, and so on. Conclusions: This study was the first to demonstrate the metabolic characteristics of PDG in vivo and its potential anti‐osteoporosis mechanism, providing the data for further pharmacological validation of PDG in the treatment of osteoporosis. [ABSTRACT FROM AUTHOR]

Rationale: Tetrandrine, the Q‐marker in Stephaniae Tetrandrae Radix, was proven to present an obvious antitumor effect. Until now, the metabolism and antitumor mechanism of tetrandrine have not been fully elucidated. Methods: The metabolites of tetrandrine in rats were profiled using ultra‐high‐performance liquid chromatography coupled with time‐of‐flight mass spectrometry. The potential antitumor mechanism of tetrandrine in vivo was predicted using network pharmacology. Results: A total of 30 metabolites were characterized in rats after ingestion of tetrandrine (10 mg/kg), including 0 in plasma, 7 in urine, 11 in feces, 9 in liver, 8 in spleen, 4 in lung, 5 in kidney, 5 in heart, and 4 in brain. This study was the first to show the metabolic processes demethylation, hydroxylation, and carbonylation in tetrandrine. The pharmacology network results showed that tetrandrine and its metabolites could regulate AKT1, TNF, MMP9, MMP2, PAK1, and so on by involving in proteoglycan tumor pathway, PI3K‐Akt signaling pathway, tumor pathway, MAPK signaling pathway, and Rap1 signaling pathway. Conclusions: The metabolism features of tetrandrine and its potential antitumor mechanism were summarized, providing data for further pharmacological validation. [ABSTRACT FROM AUTHOR]

A dual-photoelectrode self-powered photoelectrochemical (PEC) biosensing system for protein was proposed based on the liposome-assisted signal amplification strategy. The dual-photoelectrode self-powered device was constructed by integrating Ag3PO4 with bromine-doped g-C3N4 (Ag3PO4/Br-CN) as a photoanode and CuInS2 as a photocathode synchronously. Ag nanoparticle (AgNP)-encapsulated liposomes as tags were labeled on the target protein through a sandwich immunoreaction implemented in a 96-well plate. The AgNP-encapsulated liposomes were used to generate the signal regulator Ag+ for PEC detection. In the presence of Ag+, the reaction between Ag+ and Ag3PO4/Br-CN occurred to form Ag3PO4/AgBr/Br-CN ternary heterostructures. The compact contact and the matchable band-edge levels of Ag3PO4, AgBr, and Br-CN in the ternary heterostructures broaden the light absorption range and efficiently restrain the electron–hole recombination of the photoanode, producing an enhanced photocurrent response. The large loading capacity of liposomes, the fine performance of the formed ternary heterostructures, and the well-designed dual-photoelectrode self-powered PEC device endows the biosensing system with high sensitivity for protein detection. Using prostate-specific antigens as model proteins, the biosensing system exhibited a low detection limit of 3.4 × 10–13 g mL–1 with a linear range of 1.0 × 10–12 g mL–1 to 5.0 × 10–8 g mL–1. The marriage of the self-powered system with the liposome-assisted strategy not only represented a generic method for protein detection but also provided a path to fulfill the requirement of high sensitivity in PEC analysis. [ABSTRACT FROM AUTHOR]