A UHPLC-MS/MS method coupled with simple and efficient alkaline hydrolysis for free and total determination of conjugate nanomedicine: Pharmacokinetic and biodistribution study of poly (l-glutamic acid)-graft-methoxy poly (ethylene glycol)/combretastatin A4

Two Species Origins Comparison of Herba Patriniae based on Their Ingredients Profile by UPLC-QTOF/MS/MS and Orthogonal Partial Least Squares Discriminant Analysis

Herba Patriniae (HP) is widely used as a medicinal and edible material in China. Besides food value, HP attracts more attention due to its medicinal potential. Patrinia villosa Juss. ( PV ) and Patrinia scabiosaefolia Fisch. ( PS ) are the two species origins of HP. These two of HP show different effects on cell proliferation, migration, angiogenesis and anti-diabetic. As we have previously reported, PV and PS show significant differences on their anti-inflammatory ability in the same experimental model. Comparing the ingredient profiles of two different sources will not only facilitate the understanding of their medicinal effects, but also help the development and research of new activities. However, still now, there is no systematic and detailed study to compare the components of PV and PS . In present study, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was employed to achieve a high-throughput qualitative and thorough analysis of the chemical composition spectrum of HP. A total of 164 compounds were identified, among these compounds, 127 compounds were identified from PV , and 107 compounds were identified from PS . Most of the chemical components was discovered for the first time. Flavonoids, saponins, terpenoids and organic acids, as the main ingredients in PV and PS were 45.45%vs 28.46%, 12.61% vs 32.09%, 14.33% vs 22.38% and 14.58% vs 6.79%, respectively. Flavonoids are the main components of PV , while PS is rich in saponins. PV and PS were classified into two groups by principal component analysis (PCA) and screened out the main molecular differences responsible by orthogonal partial least squares discriminant analysis (OPLS-DA). All the results will be a guide for the quality control, functional activity research, or better clinic use based on the ingredients profile between these two species. Besides, this first study on ingredients profile of two species origins will be beneficial for potential and best resources utilization of both PV and PS .

A high-throughput and simultaneous determination of combretastatin A-4 phosphate and its metabolites in human plasma using HPLC-MS/MS: Application to a clinical pharmacokinetic study

To investigate the clinical pharmacokinetics of CA4P, a high-throughput high-performance liquid chromatography-tandem mass spectrometry assay with an identical positive electrospray ionization (ESI) mode was developed for the simultaneous determination of CA4P, its active metabolite CA4, and CA4 glucuronide in human plasma. CA4P and CA4 were easier to protonate in positive ESI mode, whereas CA4G was reported to produce deprotonated ion in negative ESI mode. Because the baseline separation of CA4P and CA4G could not be achieved, using MS positive/negative ion switching is not feasible. In this study, an abundant ammonium adduct ion of CA4G in ESI+ was observed as an ideal precursor ion. The final precursor/product transition pairs chosen for CA4P, CA4, and CA4G were at m/z 397/350, 317/286, and 510/317, respectively. To the best of our knowledge, it is the first report on the simultaneous quantification of CA4P, CA4, and CA4G in biological samples. The proposed method was validated, which showed a wide linear dynamic range, high selectivity and sensitivity, good repeatability, and a short run time. Compared with the literatures, the lower limits of quantification were five- and two-fold more sensitive for CA4G and CA4, respectively. Therefore, this method was successfully applied to the pharmacokinetic study of CA4P in phase I clinical trial.

Polypeptides-Drug Conjugates for Anticancer Therapy

Polypeptides are an important class of biodegradable polymers that have been widely used in drug delivery field. Owing to the controllable synthesis and robust side chain-functionalization ability, polypeptides have long been ideal candidates for conjugation with anticancer drugs. The chemical conjugation of anticancer drugs with polypeptides, termed polypeptides-drug conjugates, has demonstrated several advantages in improving pharmacokinetics, enhancing drug targeting, and controlling drug release, thereby leading to enhanced therapeutic outcomes with reduced side toxicities. This review focuses on the recent advances in the design and preparation of polypeptides-drug conjugates for enhanced anticancer therapy. Strategies for conjugation of different types of drugs, including small-molecule chemotherapeutic drugs, proteins, vascular disrupting agents, and gas molecules, onto polypeptides backbone are summarized. Finally, the challenges and future perspectives on the development of innovative polypeptides-drug conjugates for clinical cancer treatment are also presented.

Preparation of a Sensor Based on Biomass Porous Carbon/Covalent-Organic Frame Composites for Pesticide Residues Detection

In this work, a covalent-organic framework with high carbon and nitrogen content microstructures (named COF-LZU1), assisted by 3D nitrogen-containing kenaf stem composites (represented as COF-LZU1/3D-KSCs), was constructed. Moreover, it was utilized for immobilizing acetylcholinesterase (AChE) for identifying trichlorfon, a commonly applied organophosphorus (OP) pesticide. The development of COF-LZU1/3D-KSC was affirmed by SEM, PXRD, and EDXS. The findings confirmed that COF-LZU1 microstructures were uniformly developed on 3D-KSC holes using a one-step synthesis approach, which can substantially enhance the effective surface area. Also, the COF-LZU1/3D-KSC composite contains not only the nitrogen element in COF-LZU1 but also the nitrogen element in 3D-KSC, which will greatly improve the biocompatibility of the material. The AChE/COF-LZU1/3D-KSC integrated electrode was fabricated by directly fixing a large amount of AChE on the composite. At the same time, the integrated electrode had good detection efficiency for trichlorfon. Improved stabilization, a wide-linear-range (0.2–19 ng/mL), and a lower detection limit (0.067 ng/mL) have been displayed by the sensor. Therefore, this sensor can be used as an important platform for the on-site detection of OP residue.

Gut microbiome-derived lactate promotes to anxiety-like behaviors through GPR81 receptor-mediated lipid metabolism pathway

Accumulating evidence suggests that chronic stress could perturb the composition of the gut microbiota and induce host anxiety- and depression-like behaviors. In particular, microorganism-derived products that can directly or indirectly signal to the nervous system. This study sought to investigate whether high levels of Lactobacillus and lactate in the gut of rats under chronic unpredictable stress (CUS) were the factors leading to anxiety behavior. We collected faeces and blood samples in a sterile laboratory bench to study the microbiome and plasma metabolome from adult male rats age and environment matched healthy individuals. We sequenced the V3 and V4 regions of the 16S rRNA gene from faeces samples. UPLC-MS metabolomics were used to examine plasma samples. Search for potential biomarkers by combining the different data types. Finally, we found a regulated signaling pathway through the relative expression of protein and mRNA. Both lactate feeding and fecal microbiota transplantation caused behavioral abnormalities such as psychomotor malaise, impaired learning and memory in the recipient animals. These rats also showed inhibition of the adenylate cyclase (AC)-protein kinase A (PKA) pathway of lipolysis after activation of G protein-coupled receptor 81 (GPR81) by lactate in the liver, as well as increased tumor necrosis factor α (TNF-α), compared with healthy controls. Furthermore, we showed that sphingosine-1-phosphate receptor 2 (S1PR2) protein expression in hippocampus was reduced in chronic unpredictable stress compared to control group and its expression negatively correlates with symptom severity. Our study suggest that the gut microbiome-derived lactate promotes to anxiety-like behaviors through GPR81 receptor-mediated lipid metabolism pathway.

Pulsatilla chinensis saponins cause liver injury through interfering ceramide/sphingomyelin balance that promotes lipid metabolism dysregulation and apoptosis

BACKGROUND

P. chinensis saponins (PRS) are pentacyclic triterpenoid bioactive constituents from Pulsatilla chinensis (Bunge) Regel. In our previous study, PRS caused chronic liver injury (CLI) with the significant changes of lipid metabolites including sphingomyelin (SM) in serum after long-term administration. The SM in the hepatocytes membrane plays an indispensable role in maintaining cell membrane stability and regulating the extracellular and intracellular signal transduction. However, it is still unknown the pathway related to SM and the mechanism of CLI on hepatocyte.

PURPOSE

The purpose of this study was to explore the hepatotoxicity mechanism of PRS in vivo and in vitro, to reveal the action of mechanism of SM and the pathway related to liver injury.

METHODS

SD rats were orally administered with PRS for 240 days and liver injury was evaluated by histological examinations. Metabolomics analysis was used to explore the liver metabolic pathway affected by PRS, and the expressions of related proteins were evaluated by western blots. To discover and elucidate the underlying mechanisms of metabolites changes induced by PRS at the cellular level, cellular morphology, MTT assays, western blots and cell membrane potential measurements were carried out using LO2 cells. Furthermore, the roles of SM and cholesterol (Chol) in hepatocyte injury were investigated individually in overload Chol and SM groups. Sphingolipid metabolic pathway related with ceramide/sphingomyelin (Cer/SM) balance was explored using cellular lipidomics and RT-PCR.

RESULTS

PRS gradually damaged the rat's liver in a time-dependent manner. The analysis of liver metabolism profiles showed that lipids metabolites were changed, including sphingolipid, bile acid, linoleic acid and fatty acid. We found that PRS induced apoptosis by interfering with bile acid-mediated sphingolipid metabolic pathway and Cer/SM balance in CLI. In in vitro experiments, PRS led to the increase of LDH leakage, depolarized cell membrane potential and caused cell membrane toxicity. Furthermore, PRS inducedG0/G1 phase cell cycle arrest in LO2 cells, simultaneously activated cellular extrinsic and intrinsic apoptosis pathways. PRS acted on SM and interfered with Cer/SM balance, which promote lipid metabolism dysregulation and apoptosis.

CONCLUSION

PRS acted on SM to interfere Cer/SM balance on LO2 cell. Both in vivo and in vitro, PRS induced Cer/SM imbalance which promoted lipid metabolism disorder and apoptosis. Apoptosis and lipids changes gradually damaged the rats liver, and ultimately developed into CLI.

Metabolite Profile Changes in Different Regions of Rat Brain Affected by Ephedra sinica

Ephedra sinica Stapf (EP) has a long medication history dating back centuries in the world. There were some reports of adverse effects in the central nervous system (CNS) resulting from administration of a drug containing EP or ephedrine. Compared with alkaloid monomer compounds, the effects of EP on the CNS are usually neglected. It is necessary to explore CNS affection which is helpful to use EP rationally. However, the affection and the changes of substances by EP in the brain are still unknown because the effects of drug on the brain also exhibit different tendency and distribution and usually lead to diversity of metabolite alteration in different regions. In this study, metabolomics based on different brain regions was used to investigate the affection mechanism of EP in the CNS. The metabolites in 6 brain regions from a rat that underwent oral administration with EP for 14 days were determined by UPLC/Q-TOF-MS. Brain histological examinations showed that there were no obvious lesions in EP administration groups. Partial least square-discriminant analysis (PLS-DA) displayed that there were significant separations between control and EP administration groups. 7 CNS biomarkers were found and identified in different regions. 3 metabolic pathways were disturbed by EP, including amino acid metabolism, phospholipid metabolism, and amino sugar metabolism. Furthermore, all biomarkers were significantly changed in the cortex after administration. This study may be helpful to understand the affection mechanism of EP in the CNS and improve cognition of brain regional characteristics.

Rapid identification and pharmacokinetic studies of multiple active alkaloids in rat plasma through UPLC-Q-TOF-MS and UPLC-MS/MS after the oral administration of Zanthoxylum nitidum extract

Zanthoxylum nitidum (Roxb.) DC. (ZN) belongs to the genus Zanthoxylum of Rutaceae and has various chemical ingredients and pharmacologic effects. Alkaloids are its main active constituents responsible for diverse pharmacologic effects, such as anti-tumor, anti-bacterial, anti-inflammatory, and analgesic activities. The chemical and pharmacological effects of ZN are well reported, but the in vivo pharmacokinetic profiles of its main active alkaloids are poorly investigated. This study aims to elucidate the absorbed constituents and pharmacokinetic behavior of main active ingredients in rat plasma after the oral administration of ZN extract. The absorbed constituents in rat plasma were qualitatively analyzed using ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Ultra-high-performance liquid chromatography with triple quadrupole mass spectrometry (UPLC-MS/MS) method was developed for the simultaneous determination and pharmacokinetic studies of dihydrochelerythrine (DHCHE), nitidine chloride (NIT), chelerythrine (CHE), sanguinarine (SAN), liriodenine (LIR), skimmianine (SKI), γ-fagarine (FAG), and dictamnine (DIC) in rat plasma. Eighteen prototypes and metabolites were identified according to exact mass, characteristic diagnostic fragment ions, and reference standards. The established UPLC-MS/MS quantitative method met the requirements of FDA for biological analysis methods. Method validation showed that this method has good linearity (r ≥ 0.9910), precision (RSD ≤ 18.63 %), accuracy (88.11 %-117.50 %), and stability. The limit of detection (LOD) could reach 1 ng/mL, and the limit of quantitation could reach 2 ng/mL. The plasma drug concentration of benzophenanthridine alkaloids, such as NIT, CHE, and DHCHE, were still low even after dose differences were deducted. For the furan quinoline alkaloids (such as SKI, FAG, and DIC), only SKI showed high plasma drug concentration, although SKI content comprised only approximately 1/6 of benzophenanthridine alkaloids. This study is the first to simultaneously determine the above-mentioned active alkaloids in rat plasma and would contribute to the comprehensive understanding of in vivo pharmacokinetic behavior on active alkaloids in ZN extract.

Therapeutic potential of polypeptide-based conjugates: Rational design and analytical tools that can boost clinical translation

The clinical success of polypeptides as polymeric drugs, covered by the umbrella term "polymer therapeutics," combined with related scientific and technological breakthroughs, explain their exponential growth in the development of polypeptide-drug conjugates as therapeutic agents. A deeper understanding of the biology at relevant pathological sites and the critical biological barriers faced, combined with advances regarding controlled polymerization techniques, material bioresponsiveness, analytical methods, and scale up-manufacture processes, have fostered the development of these nature-mimicking entities. Now, engineered polypeptides have the potential to combat current challenges in the advanced drug delivery field. In this review, we will discuss examples of polypeptide-drug conjugates as single or combination therapies in both preclinical and clinical studies as therapeutics and molecular imaging tools. Importantly, we will critically discuss relevant examples to highlight those parameters relevant to their rational design, such as linking chemistry, the analytical strategies employed, and their physicochemical and biological characterization, that will foster their rapid clinical translation.

Yttrium(iii) coordination polymer micro/nanospheres with single ligand and dual ligands

In this work, yttrium(iii) coordination polymer (Y-CP) ball-flower-shaped microparticles with diameters ranging from 5 μm to 10 μm were synthesized using vanillin and asparagine as ligands under solvothermal conditions at 150 °C for 24 h. Then, we investigated the reaction influencing factors such as the concentration of reactants (involving vanillin, asparagine, and rare earth), reaction temperature, and reaction time. Both uniform and sphere-like nanoparticles with an average size of ∼50 nm were obtained using vanillin as a ligand at 120 °C for 12 h. Furthermore, the products were characterized and the results of cytotoxicity research demonstrated that the nanoparticles had low cytotoxicity and the coordination polymer nanospheres were perfectly biocompatible.

In this work, yttrium (III) coordination polymer (Y-CP) ball-flower-shaped microparticles with diameters ranging from 5 μm to 10 μm were synthesized using vanillin and asparagine as ligands under solvothermal conditions at 150 °C for 24 h.

Nitrogen-containing three-dimensional biomass porous carbon materials as an efficient enzymatic biosensing platform for glucose sensing

Schematic illustration of the fabrication and structure of the 3D-CVS/GOD electrode.