Validated UPLC-MS/MS method for quantification of seven compounds in rat plasma and tissues: Application to pharmacokinetic and tissue distribution studies in rats after oral administration of extract of Eclipta prostrata L

A comprehensive review on wedelolactone: natural sources, total synthesis, and pharmacological activities

Plant-derived natural products have long been a vital source for developing therapeutic drugs. Wedelolactone (WDL), a coumestan isolated from Eclipta prostrata, Wedelia calendulacea, Wedelia chinensis, and Sphagneticola trilobata, demonstrates a broad spectrum of therapeutic potential, including anticancer, anti-inflammatory, anti-obesity, anti-myotoxic, antimicrobial, anti-diabetic, and tissue-protective activities. This review synthesizes information on the isolation, total synthesis, pharmacological activity, underlying mechanisms, and pharmacokinetic properties of WDL. Additionally, it offers insights into potential clinical applications and future drug discovery avenues utilizing WDL or its derivatives, either independently or in combination with other pharmaceuticals.

Long-term effects of luteolin in a mouse model of nephropathic cystinosis

In infantile nephropathic cystinosis, variants of the CTNS gene cause accumulation of cystine in lysosomes, causing progressive damage to most organs. Patients usually present before 1 year of age with signs of renal Fanconi syndrome. Cysteamine therapy allows cystine clearance from lysosomes and delays kidney damage but does not prevent progression to end-stage kidney disease, suggesting that pathways unrelated to cystine accumulation are also involved. Among these, impaired autophagy, altered endolysosomal trafficking, and increased apoptosis have emerged in recent years as potential targets for new therapies. We previously showed that luteolin, a flavonoid compound, improves these abnormal pathways in cystinotic cells and in zebrafish models of the disease. Herein, we have investigated if prolonged luteolin treatment ameliorates kidney damage in a murine model of cystinosis. To this end, we have treated Ctns-/- mice from 2 to 8 months with 150 mg/kg/day of luteolin. No significant side effects were observed. Compared to untreated animals, analyses of kidney cortex samples obtained after sacrifice showed that luteolin decreased p62/SQSTM1 levels (p <0.001), improved the number, size, and distribution of LAMP1-positive structures (p <0.02), and decreased tissue expression of cleaved caspase 3 (p <0.001). However, we did not observe improvements in renal Fanconi syndrome and kidney inflammation. Kidney function remained normal during the time of the study. These results indicate that luteolin has positive effects on the apoptosis and endo-lysosomal defects of cystinotic proximal tubular cells. However, these beneficial effects did not translate into improvement of renal Fanconi syndrome.

Luteolin as a potential hepatoprotective drug: Molecular mechanisms and treatment strategies

Luteolin is a flavonoid widely present in various traditional Chinese medicines. In recent years, luteolin has received more attention due to its impressive liver protective effect, such as metabolic associated fatty liver disease, hepatic fibrosis and hepatoma. This article summarizes the pharmacological effects, pharmacokinetic characteristics, and toxicity of luteolin against liver diseases, and provides prospect. The results indicate that luteolin improves liver lesions through various mechanisms, including inhibiting inflammatory factors, reducing oxidative stress, regulating lipid balance, slowing down excessive aggregation of extracellular matrix, inducing apoptosis and autophagy of liver cancer cells. Pharmacokinetics research manifested that due to metabolic effects, the bioavailability of luteolin is relatively low. It is worth noting that appropriate modification, new delivery systems, and derivatives can enhance its bioavailability. Although many studies have shown that the toxicity of luteolin is minimal, strict toxicity experiments are still needed to evaluate its safety and promote its reasonable development. In addition, this study also discussed the clinical applications related to luteolin, indicating that it is a key component of commonly used liver protective drugs in clinical practice. In view of its excellent pharmacological effects, luteolin is expected to become a potential drug for the treatment of various liver diseases.

Wedelolactone: A molecule of interests

BACKGROUND

The search for bioactive molecules from medicinal plants of the family Asteraceae has been one of the targets in various phytochemical and pharmacological investigations for many years. According to these studies, wedelolactone, a coumestan of the secondary metabolite type, is a key compound found in several Eclipta and Wedelia herbal plants. To date, numerous experimental studies with intention of highlighting its role in drug development programs were carried out, but an extensive review is not sufficient.

OBJECTIVE

The current review aims to fill the gaps in extensive knowledge about phytochemistry, synthesis, pharmacology, and pharmacokinetics of coumestan wedelolactone.

MATERIALS AND METHODS

The databases Google Scholar, Scopus, PubMed, Web of Science, Science Direct, Medline, and CNKI were used to compile the list of references. In order to find references, "wedelolactone" was considered separately or in combination with "phytochemistry", "synthesis", "pharmacology", and "pharmacokinetics." Since the 1950s, >100 publications have been collected and reviewed.

RESULTS

Wedelolactone is likely to be a characteristic metabolite of two genera Eclipta and Wedelia, the family Asteraceae, while it could be synthetically derived from mono-phenol derivatives, through Sonogashira and cross-coupling reactions. Numerous biomedical investigations on wedelolactone revealed that its pharmacological values included anticancer, antiinflammatory, antidiabetic, antiobesity, antimyotoxicity, antibacterial, antioxidant, antivirus, anti-aging, cardiovascular, serine protease inhibition, especially its protective health benefits to living organs such as liver, kidney, lung, neuron, eye, bone, and tooth. The combination of wedelolactone and potential agents is a preferential approach to improve its biomedical values. Pharmacokinetic study exhibited that wedelolactone was metabolized in rat plasma due to hydrolysis, open-ring lactone, methylation, demethylation, and glucuronidation.

CONCLUSIONS

Wedelolactone is a promising agent with the great pharmacological values. Molecular mechanisms of the actions of this compound at both in vitro and in vivo levels are now available. However, reports highlighting biosynthesis and structure-activity relationship are still not adequate. Moreover, chemo-preventive records utilizing nano-technological approaches to improve its bioavailability are needed since the solubility in the living body environment is still limited.

UPLC-MS/MS Assay for Quantification of Wedelolactone and Demethylwedelolactone in Rat Plasma and the Application to a Preclinical Pharmacokinetic Study

AIMS AND OBJECTIVE

Wedelolactone and demethylwedelolactone are the two major coumarin constituents of Herba Ecliptae. The objective of this work was to develop and validate a sensitive, rapid, and robust UPLC-MS/MS method for the simultaneous quantification of wedelolactone and demethylwedelolactone in rat plasma.

MATERIALS AND METHODS

Wedelolactone and demethylwedelolactone were extracted from rat plasma by protein precipitation with acetonitrile. Electrospray ionization in negative mode and selected reaction monitoring (SRM) were used for wedelolactone and demethylwedelolactone at the transitions m/z 312.8→298.0 and m/z 299.1→270.6, respectively. Chromatographic separation was conducted on a Venusil C₁₈ column (50 mm × 2.1 mm, 5 μm) with isocratic elution of acetonitrile-0.1% formic acid in water (55:45, v/v) at a flow rate of 0.3 mL/min. A linear range was observed over the concentration range of 0.25-100 ng/mL for wedelolactone and demethylwedelolactone.

RESULTS

They reached their maximum plasma concentrations (C_max, 74.9±13.4 ng/mL for wedelolactone and 41.3±9.57 ng/mL for demethylwedelolactone) at the peak time (T_max) of 0.633 h and 0.800 h, respectively. The AUC_0-t value of wedelolactone (260.8±141.8 ng h/mL) was higher than that of demethylwedelolactone (127.4±52.7 ng h/mL) by approximately 2-fold, whereas the terminal elimination half-life (t_1/2) of wedelolactone (2.20±0.59 h) showed the approximately same as that of demethylwedelolactone (2.08±0.69 h).

CONCLUSION

Based on full validation according to US FDA guidelines, this UPLC-MS/MS method was successfully applied to a pharmacokinetic study in rats.

Integrated Phytochemical Analysis Based on UPLC-MS/MS and Network Pharmacology Approaches to Explore the Effect of Odontites vulgaris Moench on Rheumatoid Arthritis

Odontites vulgaris Moench has the effect of clearing away heat, detoxification, dispelling wind, and clearing dampness. In this study, the potential anti-inflammatory compounds of O. vulgaris were investigated using ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) combined with the network pharmacology approach and further confirmed on an LPS-activated RAW 264.7 macrophage model. Monomer compounds were prepared from the active fraction using modern advanced separation and purification methods. UPLC-Q-Exactive HRMS was used to identify the chemical compounds in the active fractions of O. vulgaris. D-mannitol, geniposidic acid, salidroside, shanzhiside methyl ester, eleutheroside B, geniposide, 7,8-dihydroxycoumarin, gardoside methyl ester, arenarioside, vanillic acid, p-hydroxy-cinnamic acid, melampyroside, syringaresinol, tricin, and diosmetin were isolated from O. vulgaris for the first time. A compound database of O. vulgaris was established based on the existing literature to predict the mechanism of O. vulgaris in the treatment of rheumatoid arthritis. The results suggest that the PI3K-Akt pathway mediates O. vulgaris and deserves more attention in the treatment of RA. Finally, the anti-rheumatoid arthritis effects of the four target compounds were validated with the decreased levels of NO, TNF-α, IL-6 and IL-1β in RAW 264.7 macrophage cells treated with LPS. The present study explored the potential targets and signaling pathways of O. vulgaris in the treatment of RA, which may help to illustrate the mechanisms involved in the action of O. vulgaris and may provide a better understanding of the relationship between O. vulgaris and RA. This study provides novel insights into the development of new drugs and utilization of Mongolian traditional Chinese medicine resources.

Potent Inhibitors of Organic Anion Transporters 1 and 3 From Natural Compounds and Their Protective Effect on Aristolochic Acid Nephropathy

Organic anion transporters 1 and 3 (OAT1 and OAT3) play a critical role in renal drug-drug interactions and are involved in the nephrotoxicity of many anionic xenobiotics. To date, relatively little is known about the interaction of natural compounds with OAT1 and OAT3. Of the 270 natural compounds screened in the present study, 21 compounds inhibited OAT1 and 45 compounds inhibited OAT3. Further concentration-dependent studies identified 7 OAT1 inhibitors and 10 OAT3 inhibitors with IC50 values of <10 μM, and most of them were flavonoids, the most commonly ingested polyphenolic compounds in the diet and herbal products. Computational modeling of OAT1 and OAT3 revealed the important residues for the recognition of inhibitors. The two strong OAT inhibitors, namely wedelolactone and wogonin, were evaluated for their in vivo interactions with the OAT substrate aristolochic acid I (AAI), a natural compound causing aristolochic acid-induced nephropathy (AAN) in many species. The cytotoxicity of AAI increased in two OAT-overexpressing cell lines, with more cytotoxicity in OAT1-overexpressing cells, suggesting a more important role of OAT1 than OAT3 in AAN. Both wedelolactone and wogonin markedly increased serum AAI concentrations in AAI-treated rats and ameliorated kidney injuries in AAI-treated mice. To conclude, the present findings are of significant value in understanding natural compound-drug interactions and provide a natural source for developing treatments for AAN.

Does Oral Apigenin Have Real Potential for a Therapeutic Effect in the Context of Human Gastrointestinal and Other Cancers?

Apigenin (4′, 5, 7-trihydroxyflavone) is a plant flavone that has been found to have various actions against cancer cells. We evaluated available evidence to determine whether it is feasible for apigenin to have such effects in human patients.

Apigenin taken orally is systemically absorbed and recirculated by enterohepatic and local intestinal pathways. Its bioavailability is in the region of 30%. Once absorbed from the oral route it reaches maximal circulating concentration (C_max) after a time (T_max) of 0.5–2.5h, with an elimination half-life (T¹/₂) averaging 2.52 ± 0.56h.

Using a circulating concentration for efficacy of 1–5μmol/L as the target, we evaluated data from both human and rodent pharmacokinetic studies to determine if a therapeutic concentration would be feasible. We find that oral intake of dietary materials would require heroic ingestion amounts and is not feasible. However, use of supplements of semi-purified apigenin in capsule form could reach target blood levels using amounts that are within the range currently acceptable for other supplements and medications. Modified formulations or parenteral injection are suitable but may not be necessary.

Further work with direct studies of pharmacokinetics and clinical outcomes are necessary to fully evaluate whether apigenin will contribute to a useful clinical strategy, but given emerging evidence that it may interact beneficially with chemotherapeutic drugs, this is worthy of emphasis. In addition, more effective access to intestinal tissues from the oral route raises the possibility that apigenin may be of particular relevance to gastrointestinal disorders including colorectal cancer.

Anti-perimenopausal osteoporosis effects of Erzhi formula via regulation of bone resorption through osteoclast differentiation: A network pharmacology-integrated experimental study

ETHNOPHARMACOLOGICAL RELEVANCE

Erzhi formula (EZF) consists of Ecliptae herba (EH) and Fructus Ligustri Lucidi (FLL) at a ratio 1:1, and constitutes a well-known formula in China that is commonly used for treating menopausal diseases.

AIM OF THE STUDY

In this study, we explored the pharmacologic actions and potential molecular mechanisms underlying EZF's action in preventing and treating osteoporosis.

MATERIALS AND METHODS

The active components and related targets of EZF's anti-osteoporotic effects were predicted by network pharmacology, and functional enrichment analysis was also performed. We then used an osteoporosis model of ovariectomized (OVX) mice to detect the effects of EZF on osteoporosis.

RESULTS

The results from network pharmacology identified a total of 10 active ingredients from EH and 13 active ingredients from FLL that might affect 65 potential therapeutic targets. GO enrichment analysis revealed that EZF affected bone tissue primarily via hormone (particularly estradiol)-related pathways and bone resorption by osteoclast differentiation. KEGG analysis demonstrated that bone-related factors such as Runt-related transcription factor 2 (Runx2), Ca2, estrogen receptor1 (ESR1), androgen receptors (AR), and TNFα served as the primary targets during osteoclastic differentiation. In vivo experiments showed that the formula significantly improved the diminution in estrogen and the subsequent uterine atrophy induced by ovariectomy (P < 0.01 or 0.05), implying that the EZF exerted its actions via regulation of estradiol and the nourishing effects of the uterus in OVX mice. Dual-energy X-ray absorptiometry and micro-CT showed that EZF significantly inhibited bone loss and improved bone micro-architecture by statistically increasing the number of bone trabeculae and decreasing the separation of bone trabeculae in OVX mice (P < 0.01 or 0.05); EZF also inhibited bone loss and enhanced bone-fracture load. Furthermore, we confirmed that EZF reduced the calcium concentrations, augmented protein and mRNA levels for Runx2 in the bone marrow, and reduced PPARγ levels. RANKL-a key downstream regulatory protein of many targets that was referred to in our results of network pharmacology as being involved in the regulation of osteoclastogenesis-was significantly diminished by EZF; it also elevated OPG content. In addition, we used monocytes of bone-marrow origin to detect the effects of the potential components of EZF on osteoclast differentiation and found that wedelolactone, oleanolic acid, echinocystic acid, luteolin, and luteolin-7-o-glucoside significantly inhibited osteoclast differentiation from monocytes induced by 25 ng/mL MCSF and 50 ng/mL RANKL (P < 0.01 or 0.05).

CONCLUSIONS

Our present study indicated that EZF significantly inhibited the bone loss induced by OVX in mice by its regulation of estradiol combined with the nourishing effect of the uterus, and that it also attenuated bone resorption by decreasing the RANKL/OPG ratio so as to inhibit osteoclast maturation.

UPLC-MS/MS Method for the Simultaneous Quantification of Eight Compounds in Rat Plasma and Its Application to a Pharmacokinetic Study after Oral Administration of Veratrum (Veratrum nigrum L.) Extract

Veratrum nigrum L. is a well-known traditional Chinese medicine with a lot of pharmacological activities including antihypertensive, anticancer, and antifungal effects. In the current experiment, a rapid and sensitive UPLC-MS/MS method that takes only 7 min run time has been established and validated for simultaneous determination of eight bioactive compounds including cyclopamine, jervine, veratramine, polydatin, quercetin, apigenin, resveratrol, and veratrosine in rat plasma. The chromatographic separation of analytes and internal standard was performed on a Phenyl-Hexyl column (2.1 × 100 mm, 1.7 μm) with the mobile phase consisting of water (0.1% formic acid) and acetonitrile at a flow rate of 0.3 mL/min. An electrospray ionization (ESI) source was used to detect the samples in both positive and negative ion modes. The intra- and interday precisions of the compounds were less than 9.5% and the accuracy ranged from -10.8% to 10.4%. The extraction recoveries of the compounds were in the range of 85.1 ± 1.5% to 102.6 ± 8.0%, and the matrix effect ranged from 91.2 ± 4.5% to 113.8 ± 1.5%. According to the results of the stability test, the eight compounds have good stability under various conditions and the relative standard deviation (RSD) less than 13.2%. The pharmacokinetic parameters of the eight compounds in rat plasma after oral administration of Veratrum nigrum L. extract were successfully determined by the established UPLC-MS/MS method.

Pharmacokinetic Study of Multiple Components of Gelsemium elegans in Goats by Ultra-Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry

Gelsemium elegans (G. elegans) has been used in traditional Chinese medicine. This plant is highly toxic to humans, but can promote the growth of pigs and goats in the veterinary clinic. It is a very complex mixture containing tens or hundreds of different components. Therefore, multiple-component pharmacokinetic studies of G. elegans are a major challenge due to the lack of authentic standards of the components. The purpose of this study was to investigate the plasma pharmacokinetics of multiple components after a single oral dose of G. elegans in goat using a sensitive ultra-performance liquid chromatography coupled to tandem mass spectrometry method for the simultaneous semiquantification of multiple alkaloids without standards. The method was validated in terms of the specificity, LOD, LOQ, linearity, accuracy, precision and matrix effects. To validate the global pharmacokinetic characteristics, the results obtained from the semiquantitative analysis of three authentic compounds (gelsemine, koumine and humantenmine) were compared with the absolute quantification from our recently published method. The results showed that the two methods had similar analytical results, and the obtained values of Tmax, T1/2 and MRT0-t of the three alkaloids were similar between the two methods. In addition, the values of Cmax and AUC0-t of the three alkaloids after normalization were close to the real values, which indicated that this semiquantitative method could be used in the pharmacokinetic study of multiplecomponents. Then the pharmacokinetic parameters of 23 other G. elegans alkaloids in goats were obtained. The results suggested that the gelsedine-type alkaloids were the major active ingredients that predict and explain the efficacy and toxicity of G. elegans.