Determination of eleven components in rat plasma by UPLC-MS/MS and GC-MS for pharmacokinetic studies after oral administration of Citri Reticulatae Pericarpium extract.

Citri Reticulatae Pericarpium (CRP) is used as common health-care food and traditional Chinese medicine (TCM), which exerts pharmacological effects, such as anti-cardiovascular, anti-tumor, anti-oxidant, anti-inflammatory, anti-virus, hepatoprotective, blood pressure-lowering and neuroprotective. In this study, reliable, and sensitive ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) methods were developed and validated for the determination of eleven active components in rat plasma after oral administration of the CRP extract. The results of this method exhibited that the specificity, linearity (r > 0.999), precision and accuracy (the coefficient of variation (CV) < 11.5 %), recovery (52.9-107.9 %), matrix effects (63.8-107.5 %), and stability (CV < 10.8 %) met all requirements for the quantitation of plasma samples. The pharmacokinetic results showed that the Tmax of flavone glycosides was less than 0.7 h, and that of polymethoxyflavones and volatile components were within 1-7 h. Meanwhile, the area-under-the-curve (AUC) and concentration maximum (Cmax) of hesperidin, nobiletin, tangeretin, and D-limonene were higher than those of the other components, suggesting that the plasma exposure levels of these constituents were higher in CRP. The present research lays a foundation for elucidating the therapeutic material basis and provides a reference for further scientific research and clinical application of CRP.

Mesoporous silica nanoparticles as a drug delivery mechanism.

Research in intelligent drug delivery systems within the field of biomedicine promises to enhance drug efficacy at disease sites and reduce associated side effects. Mesoporous silica nanoparticles (MSNs), characterized by their large specific surface area, appropriate pore size, and excellent biocompatibility, have garnered significant attention as one of the most effective carriers for drug delivery. The hydroxyl groups on their surface are active functional groups, facilitating easy functionalization. The installation of controllable molecular machines on the surface of mesoporous silica to construct nanovalves represents a crucial advancement in developing intelligent drug delivery systems (DDSs) and addressing the issue of premature drug release. In this review, we compile several notable and illustrative examples of MSNs and discuss their varied applications in DDSs. These applications span regulated and progressive drug release mechanisms. MSNs hold the potential to enhance drug solubility, improve drug stability, and mitigate drug toxicity, attributable to their ease of functionalization. Furthermore, intelligent hybrid nanomaterials are being developed, featuring programmable properties that react to a broad spectrum of stimuli, including light, pH, enzymes, and redox triggers, through the use of molecular and supramolecular switches.

Investigation of the drug-drug interaction and incompatibility mechanism between Aconitum carmichaelii Debx and Pinellia ternata (Thunb.) Breit.

ETHNOPHARMACOLOGICAL RELEVANCE: The combination of Aconitum carmichaelii Debx (Chuanwu, CW) and Pinellia ternata (Thunb.) Breit (Banxia, BX) forms an herbal pair within the eighteen incompatible medicaments (EIM), indicating that BX and CW are incompatible. However, the scientific understanding of this incompatibility mechanism, especially the corresponding drug-drug interaction (DDI), remains complex and unclear. AIM OF THE STUDY: This study aims to explain the DDI and potential incompatibility mechanism between CW and BX based on pharmacokinetics and cocktail approach. MATERIALS AND METHODS: Ultraperformance liquid chromatography-tandem mass spectrometry methods were established for pharmacokinetics and cocktail studies. To explore the DDI between BX and CW, in the pharmacokinetics study, 10 compounds were determined in rat plasma after administering CW and BX-CW herbal pair extracts. In the cocktail assay, the pharmacokinetic parameters of five probe substrates were utilized to assess the influence of BX on cytochrome P450 (CYP) isoenzyme (dapsone for CYP3A4, phenacetin for CYP1A2, dextromethorphan for CYP2D6, tolbutamide for CYP2C9, and omeprazole for CYP2C19). Finally, the DDI and incompatibility mechanism of CW and BX were integrated to explain the rationality of EIM theory. RESULTS: BX not only enhances the absorption of aconitine and benzoylaconine but also accelerates the metabolism of mesaconitine, benzoylmesaconine, songorine, and fuziline. Moreover, BX affects the activity of CYP enzymes, which regulate the metabolism of toxic compounds. CONCLUSIONS: BX altered the activity of CYP enzymes, consequently affecting the metabolism of toxic compounds from CW. This incompatibility mechanism may be related to the increased absorption of these toxic compounds in vivo.

UV-Triggered Drug Release from Mesoporous Titanium Nanoparticles Loaded with Berberine Hydrochloride: Enhanced Antibacterial Activity.

Mesoporous titanium nanoparticles (MTN) have always been a concern and are considered to have great potential for overcoming antibiotic-resistant bacteria. In our study, MTN modified with functionalized UV-responsive ethylene imine polymer (PEI) was synthesized. The characterization of all products was performed by different analyses, including SEM, TEM, FT-IR, TGA, XRD, XPS, and N2 adsorption-desorption isotherms. The typical antibacterial drug berberine hydrochloride (BH) was encapsulated in MTN-PEI. The process exhibited a high drug loading capacity (22.71 ± 1.12%) and encapsulation rate (46.56 ± 0.52%) due to its high specific surface area of 238.43 m2/g. Moreover, UV-controlled drug release was achieved by utilizing the photocatalytic performance of MTN. The antibacterial effect of BH@MTN-PEI was investigated, which showed that it could be controlled to release BH and achieve a corresponding antibacterial effect by UV illumination for different lengths of time, with bacterial lethality reaching 37.76% after only 8 min of irradiation. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the nanoparticles have also been studied. The MIC of BH@MTN-PEI was confirmed as 1 mg/mL against Escherichia coli (E. coli), at which the growth of bacteria was completely inhibited during 24 h and the concentration of 5 mg/mL for BH@MTN-PEI was regarded as MBC against E. coli. Although this proof-of-concept study is far from a real-life application, it provides a possible route to the discovery and application of antimicrobial drugs.

Preparation, Characterization, and Evaluation of Mesoporous Silica Nanoparticles in Enhancing Oral Bioavailability of Poorly Water-Soluble Drugs.

BACKGROUND: Breviscapine (BVP) is one of the extracts of several flavonoids of Erigeron breviscapus, which has been widely used in the treatment of cerebral infarction and its sequelae, cerebral thrombus, coronary heart disease, and angina pectoris. But BVP has poor solubility. OBJECTIVE: The objective of the study is to develop mesoporous silica nanoparticles (MSNs) that can be loaded with a drug with poor water solubility. The MSNs, which were designed for oral administration, enhanced both the dissolution rate and drug loading capacity. METHODS: The use of MSNs as an oral drug delivery system was investigated by SEM, TEM, BETBJH, XRD, FT-IR, and HPLC. Additionally, we examined the oral bioavailability of BVP loaded onto MSNs and examined the cellular cytotoxicity of MSNs. RESULTS: The results indicate that the oral bioavailability of BVP after loading onto MSNs was greater than that of a marketed product. Furthermore, we studied the mechanism by which MSNs enhance the oral absorption of BVP. CONCLUSION: MSNs have the potential to enhance the oral bioavailability of poorly water-soluble drugs by accelerating the drug dissolution rate.

Spectrum-effect relationship study between ultra-high-performance liquid chromatography fingerprints and anti-hepatoma effect in vitro of Cnidii Fructus.

Cnidii Fructus, derived from the dried ripe fruit of Cnidium monnieri (L.) Cuss, has the effect of warming kidneys and invigorating Yang. This study established the spectrum-effect relationships between ultra-high-performance liquid chromatography (UHPLC) fingerprints and the antitumor activities of Cnidii Fructus on human hepatocellular carcinoma (HepG2) cells. In UHPLC fingerprints, 19 common peaks were obtained, and 17 batches of herbs had similarity >0.948. In Cell Counting Kit-8 (CCK-8) test, 17 batches of Cnidii Fructus extract significantly inhibited the proliferation of HepG2 cells to different degrees, showing different half-maximal inhibitory concentration (IC50) values. Furthermore, gray correlation analysis, Pearson's analysis, and orthogonal partial least squares discriminant analysis were performed to screen out eight components. The analysis of mass spectrum data and a comparison with standards revealed that the eight components were methoxsalen, isopimpinellin, osthenol, imperatorin, osthole, ricinoleic acid, linoleic acid, and oleic acid. The verification experiments by testing single compounds indicated that these eight compounds were the major anti-hepatoma compounds in Cnidii Fructus. This work provides a model combining UHPLC fingerprints and antitumor activities to study the spectrum-effect relationships of Cnidii Fructus, which can be used to determine the principal components responsible for the bioactivity.