Inhibitory effects of lupeal acetate of Cortex periplocae on N-nitrosomethylbenzylamine-induced rat esophageal tumorigenesis

Traditional Chinese Medicine Therapy for Esophageal Cancer: A Literature Review

Esophageal cancer (EC) is the sixth leading cause of cancer-related deaths worldwide. Western medicine has played a leading role in its treatment, but its prognosis remains unsatisfactory. Therefore, the development of effective therapies is important. Traditional Chinese medicine (TCM) has been practiced for thousands of years, and involves taking measures before diseases occur, deteriorate, and recur. Interestingly, there is growing evidence that TCM can improve the therapeutic effects in reversing precancerous lesions, inhibiting the recurrence and metastasis of EC. In this article, we review traditional Chinese herbs and formulas that have preventive and therapeutic effects on EC, summarize the application and research status of TCM in patients with EC, and discuss its shortcomings and prospects in the context of translational, evidence-based, and precision medicine.

Simultaneous determination of periplocin, periplocymarin, periplogenin, periplocoside M and periplocoside N of Cortex Periplocae in rat plasma and its application to a pharmacokinetic study

A sensitive and specific ultra-performance liquid chromatographic-tandem mass spectrometric method was developed and validated to simultaneously determine periplocin, periplocymarin (PM), periplogenin (PG), periplocoside M (PSM) and periplocoside N (PSN) in rat plasma. Acetonitrile was employed to precipitate plasma with appropriate sensitivity and acceptable matrix effects. Chromatographic separation was performed using a Waters HSS T3 column with a gradient elution using water and acetonitrile both containing 0.1% formic acid and 0.1 mm ammonium formate within 8 min. Detection was performed in positive ionization mode using multiple reaction monitoring. The method was fully validated in terms of selectivity, linearity, accuracy, precision, recovery, matrix effects and stability. Using this method, the concentrations of periplocin, PM, PG, PSM and PSN were established after oral administration of Cortex Periplocae extract to rats, and the pharmacokinetic characteristics of periplocin, PM, PG, PSM and PSN were assessed. Generally, PM, PG, PSM and PSN were eliminated slowly and their half-lives were all >8 h. In addition, the systemic exposure of PSM showed significant differences between genders with more than 10 times higher area under the concentration-time curve in female rats than in male rats. The findings of this study provide useful information for further research on Cortex Periplocae.

In Vitro Metabolic Profiling of Periplogenin in Rat Liver Microsomes and its Associated Enzyme-kinetic Evaluation

Background:

Periplogenin, an active ingredient in Cortex Periplocae, is widely noted for its multiple biological activities; however, the metabolism of this compound has been scarcely investigated. The present report proposed the in vitro metabolic profiling and reaction pathways of periplogenin in rat liver microsomes.

Method and Results:

The metabolites of periplogenin in rat liver microsomes were analyzed. Two main metabolites, namely 14-hydroxy-3-oxo-14β-carda-4, 20 (22)-dienolide and 5, 14-dihydroxy-3-oxo-5β, 14β-card-20(22)-enolide were identified by HPLC-MSn, 1H-NMR and 13C-NMR. HPLC method was established for the simultaneous determination of periplogenin and its related metabolites (M0, M1 and M2), which was performed on Waters ODS column with a methanol-water solution (53:47, v/v) as mobile phase and descurainoside as an internal standard at 220 nm. The linearity ranges of M0, M1 and M2 were 0.64-820.51, 0.68-864.86 and 0.64-824.74 μM respectively with the regression coefficient (R2) above 0.9995. The limits of quantitation for these metabolites (M0, M1 and M2) were 0.18, 0.22 and 0.15 μM respectively. The developed method was also accurate (with relative errors of -3.6% to 3.2%) and precise (with relative standard deviations below 7.9%). The recoveries of the three analytes were above 85.7% with stability in the range of -2.4% to 3.6%. The enzyme-kinetic parameters of periplogenin including Vmax (6.08 ± 0.19 nmol/mg protein/min), Km (288.62 ± 14.54 μM) and Clint (21 ± 1.0 μL/min/mg protein) were calculated using nonlinear regression analysis.

Conclusion:

These findings significantly highlighted the metabolic pathways of periplogenin and also provided some reference data for future pharmacokinetic and pharmacodynamic studies.

Characterization of chemical components of Periplocae Cortex and their metabolites in rats using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

Periplocae Cortex, named Xiang-Jia-Pi in China, has been widely used to treat autoimmune diseases, especially rheumatoid arthritis. However, the in vivo substances of Periplocae Cortex remain unknown yet. In this study, an ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used for profiling the chemical components and related metabolites of Periplocae Cortex. A total of 98 constituents were identified or tentatively characterized in Periplocae Cortex: 42 C21 steroidal glycosides, 10 cardiac glycosides, 23 organic acids, 4 aldehydes, 7 triterpenes, and 12 other types. Among them, 18 components were unambiguously identified by comparison with reference standards. In addition, 176 related xenobiotics (34 prototypes and 142 metabolites) were screened out and characterized in rats' biosamples (plasma, urine, bile, and feces) after the oral administration of Periplocae Cortex. Moreover, the metabolic fate of periplocoside S-4a, a C21 steroidal glycoside, was proposed for the first time. In summary, phase II reactions (methylation, glucuronidation, and sulfation), phase I reactions (hydrolysis reactions, oxygenation, and reduction), and their combinations were the predominant metabolic reactions of Periplocae Cortex in rat. It is the first report to reveal the in vivo substances and metabolism feature of Periplocae Cortex. This study also provided meaningful information for further pharmacodynamics study of Periplocae Cortex, as well as its quality control research.

Involvement of Glutathione Depletion in Selective Cytotoxicity of Oridonin to p53-Mutant Esophageal Squamous Carcinoma Cells

Oridonin, a diterpenoid compound isolated from traditional Chinese medicine Rabdosia rubescens, has shown antitumor effects to esophageal cancer. However, its molecular mechanism is not fully understood, which limits its clinical application. In the present study, we used RNA-seq analysis to check the transcriptome changes after oridonin treatment and we found genes controlling the GSH-ROS system were up-regulated, namely SLC7A11, TXNRD1, TRIM16, SRXN1, GCLM, and GCLC. Furthermore, our data suggest that oridonin significantly increased the production of ROS in EC109 and TE1 cells, which can be inhibited by NAC. Interestingly, oridonin can dramatically reduce intracellular GSH levels in TE1 cells in a concentration and time-dependent manner. In addition, cell death caused by oridonin was strongly inhibited by GSH (1 mM), while GSSG (1 mM) had little effect. At the same time, we also found that oridonin showed selective cytotoxicity to esophageal squamous carcinoma cell with p53 mutation since mut-p53 cells had lower SLC7A11 expression, a component of the cystine/glutamate antiporter. We also found that γ-glutamyl cysteine synthetase inhibitor (BSO) synergizes with oridonin to strongly inhibit EC109 cells at a low dose. These results suggested that the antitumor effects of oridonin are based on its –SH reactivity and glutathione depletion. Esophageal squamous carcinoma cells with p53-mutation showed hypersensitivity to oridonin because of the suppression of SLC7A11 expression by p53 mutation.

Genus Periploca (Apocynaceae): A Review of Its Classification, Phytochemistry, Biological Activities and Toxicology

The genus Periploca belongs to the family Apocynaceae, which is composed of approximately ten species of plants according to incomplete statistics. Most of these plants serve as folk medicines with a long history, especially Periploca sepium and Periploca forrestii. The botanical classifications, chemical constituents, biological activities and toxicities of the genus Periploca were summarized in the literature from 1897 to early 2019. Though the botanical classification of this genus is controversial, these species are well-known to be rich sources of diverse and complex natural products-above all, cardiac steroids and C₂₁ pregnane steroids with special structures and obvious pharmacological activities. The various crude extracts and 314 isolated metabolites from this genus have attracted much attention in intensive biological studies, indicating that they are equipped with cardiotonic, anti-inflammatory, immunosuppressive, antitumor, antimicrobial, antioxidant, insecticidal and other properties. It is noteworthy that some cardiac glycosides showed hepatotoxicity and cardiotoxicity at certain doses. Therefore, in view of the medical and agricultural value of the genus Periploca, in-depth investigations of the pharmacology in vivo, the mechanisms of biological actions, and the pharmacokinetics of the active ingredients should be carried out in the future. Moreover, in order to ensure the safety of clinical medication, the potential toxicities of cardiac glycosides or other compounds should also be paid attention. This systematic review provides an important reference base for applied research on pharmaceuticals and pesticides from this genus.

Crocetin treatment inhibits proliferation of colon cancer cells through down-regulation of genes involved in the inflammation

Background

The current study was designed to investigate the effect of crocetin on the proliferation inhibition of colon cancer cells and the underlying mechanism.

Methods

MTT assay showed inhibition of proliferation of colon cancer cells in a dose based manner by crocetin treatment. At 30 µM concentration of crocetin proliferation rate of colon cancer cells was reduced to 14% after 24 h. Flow cytometry and fluorescence microscopy revealed induction of apoptosis in colon cancer cells on treatment with crocetin. The tube formation was suppressed significantly in the cultures of HUVEC treated with 30 µM concentration of crocetin compared to the control cultures.

Results

The results from transwell assay revealed a significant reduction in the population of DU-145 cells passing through filters of transwell on treatment with crocetin compared to the control cells. Treatment of the DU-145 cells with crocetin caused a significant reduction in the expression levels of NF-κB, VEGF and MMP-9. The results from RT-PCR analysis revealed a significant reduction in the expression of genes involved in inflammation including, HMGB1, IL-6 and IL-8 on treatment of DU-145 cells with crocetin. However, the expression of NAG-1 gene was increased by crocetin treatment in DU-145 cells significantly compared to the control cells.

Conclusion

Crocetin inhibits growth of colon cancer cells and prevents tube formation through induction of apoptosis. Therefore, crocetin can be used efficiently for the treatment of colon cancer.

3-Bromopyruvate inhibits cell proliferation and induces apoptosis in CD133+ population in human glioma

The study was aimed to investigate the role of 3-bromopyruvate in inhibition of CD133+ U87 human glioma cell population growth. The results demonstrated that 3-bromopyruvate inhibited the viability of both CD133+ and parental cells derived from U87 human glioma cell line. However, the 3-bromopyruvate-induced inhibition in viability was more prominent in CD133+ cells at 10 μM concentration after 48 h. Treatment of CD133+ cells with 3-bromopyruvate caused reduction in cell population and cell size, membrane bubbling, and degradation of cell membranes. Hoechst 33258 staining showed condensation of chromatin material and fragmentation of DNA in treated CD133+ cells after 48 h. 3-Bromopyruvate inhibited the migration rate of CD133+ cells significantly compared to the parental cells. Flow cytometry revealed that exposure of CD133+ cells to 3-bromopyruvate increased the cell population in S phase from 24.5 to 37.9 % with increase in time from 12 to 48 h. In addition, 3-bromopyruvate significantly enhanced the expression of Bax and cleaved caspase 3 in CD133+ cells compared to the parental cells. Therefore, 3-bromopyruvate is a potent chemotherapeutic agent for the treatment of glioma by targeting stem cells selectively.

Anticancer effects of crocetin in human esophageal squamous cell carcinoma KYSE-150 cells

Crocetin is the main pharmacologically-active component of saffron and has been considered as a promising candidate for cancer chemoprevention. The purpose of the present study was to investigate the anticancer effects of crocetin and the possible mechanisms of these properties in the esophageal squamous cell carcinoma cell line KYSE-150. The KYSE-150 cells were cultured in Dulbecco’s modified Eagle’s medium and incubated with 0, 12.5, 25, 50, 100 or 200 μmol/l crocetin for 48 h. Cell proliferation was measured using an MTT assay. Hoechst 33258 staining and observation under fluorescent microscopy were used to analyze the proapoptotic effects of crocetin. The migration rate was assessed by a wound-healing assay. The cell cycle distribution was analyzed using flow cytometry analysis subsequent to propidium iodide staining. The expression of B-cell lymphoma-2-associated X protein (Bax) and cleaved caspase 3 was determined by western blot analysis. It was found that treatment of KYSE-150 cells with crocetin for 48 h significantly inhibited the proliferation of the cells in a concentration-dependent manner, and the inhibition of proliferation was associated with S phase arrest. Crocetin was also found to induce morphological changes and cell apoptosis in a dose-dependent manner through increased expression of proapoptotic Bax and activated caspase 3. In addition, crocetin suppressed the migration of KYSE-150 cells. The present study provides evidence that crocetin exerts a prominent chemopreventive effect against esophageal cancer through the inhibition of cell proliferation, migration and induction of apoptosis. These findings reveal that crocetin may be considered to be a promising future chemotherapeutic agent for esophageal cancer therapy.