Simultaneous determination of eight bufadienolides in cinobufacini injection by HPLC coupled with triple quadrupole mass spectrometry

Modulating pancreatic cancer microenvironment: The efficacy of Huachansu in mouse models via TGF-β/Smad pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Huachansu (HCS) is a traditional Chinese medicine obtained from the dried skin glands of Bufo gargarizans and clinical uses of HCS have been approved in China to treat malignant tumors. The traditional Chinese medicine theory states that HCS relieves patients with cancer by promoting blood circulation to remove blood stasis. Clinical observation found that local injection of HCS given to pancreatic cancer patients can significantly inhibit tumor progression and assist in enhancing the efficacy of chemotherapy. However, the material basis and underlying mechanism have not yet been elucidated.

AIM OF THE STUDY

To investigate the therapeutic potential of HCS for the treatment of pancreatic cancer in in situ transplanted tumor nude mouse model. Furthermore, this study sought to elucidate the molecular mechanisms underlying its efficacy and assess the impact of HCS on the microenvironment of pancreatic cancer. To identify the antitumor effect of HCS in in situ transplanted tumor nude mouse model and determine the Chemopreventive mechanism of HCS on tumor microenvironment (TME).

METHODS

Using the orthotopic transplantation nude mouse model with fluorescently labeled pancreatic cancer cell lines SW1990 and pancreatic stellate cells (PSCs), we examined the effect of HCS on the pancreatic ductal adenocarcinoma (PDAC) microenvironment based on the transforming growth factor β (TGF-β)/Smad pathway. The expression of TGF-β, smad2, smad3, smad4, collagen type-1 genes and proteins in nude mouse model were detected by qRT-PCR and Western blot.

RESULTS

HCS significantly reduced tumor growth rate, increased the survival rate, and ameliorated the histopathological changes in the pancreas. It was found that HCS concentration-dependently reduced the expression of TGF-β1 and collagen type-1 genes and proteins, decreased the expression of Smad2 and Smad3 genes, and downregulated the phosphorylation level of Smad2/3. Additionally, the gene and protein expression of Smad4 were promoted by HCS. Further, the promoting effect gradually enhanced with the rise of HCS concentration.

CONCLUSIONS

The results demonstrated HCS could regulate the activity of the TGF-β/Smad pathway in PDAC, improved the microenvironment of PDAC and delayed tumor progression. This study not only indicated that the protective mechanism of HCS on PDAC might be attributed partly to the inhibition of cytokine production and the TGF-β/Smad pathway, but also provided evidence for HCS as a potential medicine for PDAC treatment.

Identification of potential anti-tumor targets and mechanisms of HuaChanSu injection using network pharmacology and cytological experiments in Breast cancer

HuaChanSu (HCS) or Cinobufacini injection is an aqueous extract of the dried skin of Bufo bufo gargarigans, and has anti-tumor effects. The aim of this study was to evaluate the possible therapeutic effect of HCS against breast cancer (BRCA) using cytology, network pharmacology, and molecular biology approaches. The half-inhibitory concentration (IC50) of HCS in the BRCA cells was determined by cytotoxicity assay, and were accordingly treated with high and low doses HCS in the TUNEL and scratch assays. The potential targets of HCS in the BRCA cells were identified through functional enrichment analysis and protein-protein interaction (PPI) networks, and verified by molecular docking. The expression levels of key signaling pathways-related proteins in HCS-treated BRCA cells by western blotting. HCS inhibited the proliferation and migration of MCF-7 and MDA-MB-231 cells, and induced apoptosis in a dose-dependent manner. Furthermore, we screened 289 core HCS targets against BRCA, which were primarily enriched in the PI3K-AKT, MAPK chemokines, and other. signaling pathways. In addition, PIK3CA, PIK3CD, and MTOR were confirmed as HCS targets by molecular docking. Consistent with this, we observed a reduction in the expression levels of phosphorylated PI3K, AKT, and MTOR in the HCS-treated BRCA cells. Taken together, our findings suggest that HCS inhibits the growth of BRCA cells by targeting the PI3K-AKT pathway, and warrants further investigation as a therapeutic agent for treating patients with BRCA.

Quantification of peptide components in cinobufacini injection and toad skin by ultra-high-performance liquid chromatography/triple quadrupole mass spectrometry

Cinobufacini injection is commonly used in the clinical treatment of tumors and hepatitis B, but the quality is uneven. Currently, the main focus of its quality assessment is on steroids and alkaloids. Based on a previous study, we screened four peptides with high reproducibility, responsiveness, and specificity. This research was the first to develop an ultra-high-performance liquid chromatography/triple quadrupole mass spectrometry approach for evaluating the quality of cinobufacini preparations from the peptide perspective. In this study, we have identified 230 peptides in cinobufacini injection by Q-Exactive mass spectrometry, which contains species-specific peptides. Then, we used ultra-high-performance liquid chromatography/triple quadrupole mass spectrometry to establish a quantitative method for species-specific peptides and carried out method validation. The result revealed that four peptides were linear in a specific range, and had great reproducibility, accuracy, and stability. Eventually, we evaluated the quality of eight batches of cinobufacini injections and 26 batches of toad skins using the total content of target peptides as the criterion. The outcomes demonstrated that the quality of cinobufacini injection is generally stable and the toad skin from Shandong is of the best quality. In conclusion, the quantitative approach that focuses on peptides will offer innovative perspectives on assessing the quality of cinobufacini preparations.

Comparative Pharmacokinetics of Cinobufacini Capsule and Injection by UPLC-MS/MS

Cinobufacini capsule and injection are two different formulations from the same source, obtained from the extraction of the skin of Bufo bufo gargarizans Cantor, which have been approved by the Chinese State Food and Drug Administration (CFDA) for the treatment of various cancers. Our previous study has found that the cinobufacini capsule and injection exhibited different anticancer effects, but their different pharmacokinetic behaviors, which could give a cause of that, have never been reported. So a sensitive and selective method for the simultaneous quantitation of 13 compounds in the rat plasma, including bufothionine, hellebrigenin, bufalin, gamabufotalin, telocinobufagin, cinobufagin, arenobufagin, cinobufotalin, desacetylcinobufotalin, bufotalin, pseudobufarenogin, resibufogenin, and desacetylcinobufagin, was established by using the Agilent 6460 mass spectrometer equipped with an ESI ion source in a multiple-reaction monitoring (MRM) mode. Chromatographic analysis was accomplished in 6 min by using an Agilent SB-C18 column and a mobile phase consisting of 0.1% formic acid in water and acetonitrile in an optimized gradient program at a flow rate of 0.3 ml/min. The correlation coefficients (r) of all analytes ranged from 0.9967 to 0.9996, while their lower limits of quantification ranged from 0.20 to 4.84 ng/ml. The method has been fully verified and applied for the pharmacokinetic difference study of the Cinobufacini capsule and injection in rats. The results showed that nine components could be quantitated in rat plasma samples after the administration of the cinobufacini capsule, while only bufothionine, bufalin, arenobufagin, and pseudobufarenogin could be detected in the cinobufacini injection group. Their pharmacokinetic studies indicated telocinobufagin, bufalin, desacetylcinobufagin, and arenobufagin were predicted as the potential active substances of the Cinobufacini capsule, while bufothionine was considered as a major ingredient in the cinobufacini injection due to its relatively high blood drug exposure. Also, the AUC of the nine components in cinobufacini capsule groups with three different doses showed a similar trend with significant differences, and the exposure increased with the increase of the dose. The pharmacokinetic characteristics of all major ingredients in cinobufacini capsules and injection were of wide variation, which could be used to explain differences in the efficacy of the cinobufacini capsule and injection and infer the pharmacodynamic ingredients of various cinobufacini preparations.

Network Pharmacology Study on the Pharmacological Mechanism of Cinobufotalin Injection against Lung Cancer

Cinobufotalin injection, extracted from the skin of Chinese giant salamander or black sable, has good clinical effect against lung cancer. However, owing to its complex composition, the pharmacological mechanism of cinobufotalin injection has not been fully clarified. This study aimed to explore the mechanism of action of cinobufotalin injection against lung cancer using network pharmacology and bioinformatics. Compounds of cinobufotalin injection were determined by literature retrieval, and potential therapeutic targets of cinobufotalin injection were screened from Swiss Target Prediction and STITCH databases. Lung-cancer-related genes were summarized from GeneCards, OMIM, and DrugBank databases. The pharmacological mechanism of cinobufotalin injection against lung cancer was determined by enrichment analysis of gene ontology and Kyoto Encyclopedia of Genes and Genomes, and protein-protein interaction network was constructed. We identified 23 compounds and 506 potential therapeutic targets of cinobufotalin injection, as well as 70 genes as potential therapeutic targets of cinobufotalin injection in lung cancer by molecular docking. The antilung cancer effect of cinobufotalin injection was shown to involve cell cycle, cell proliferation, antiangiogenesis effect, and immune inflammation pathways, such as PI3K-Akt, VEGF, and the Toll-like receptor signaling pathway. In network analysis, the hub targets of cinobufotalin injection against lung cancer were identified as VEGFA, EGFR, CCND1, CASP3, and AKT1. A network diagram of “drug-compounds-target-pathway” was constructed through network pharmacology to elucidate the pharmacological mechanism of the antilung cancer effect of cinobufotalin injection, which is conducive to guiding clinical medication.

Metabolites from Bufo gargarizans (Cantor, 1842): A review of traditional uses, pharmacological activity, toxicity and quality control

ETHNOPHARMACOLOGICAL RELEVANCE

Bufo gargarizans (Cantor, 1842) (BGC), a traditional medicinal animal distributed in many provinces of China, is well known for the pharmaceutical value of Chansu and Chanpi. As traditional Chinese medicines (TCMs), Chansu and Chanpi, with their broad-spectrum of therapeutic applications, have long been applied to detoxification, anti-inflammation, analgesia, etc. OVERARCHING OBJECTIVE: We critically analyzed the current evidence for the traditional uses, chemical profiles, pharmacological activity, toxicity and quality control of BGC (Bufonidae family) to provide a scientific basis for future in-depth studies and perspectives for the discovery of potential drug candidates.

METHODOLOGY

All of the available information on active constituents and TCMs derived from BGC was obtained using the keywords "Bufo gargarizans", "Chansu", "Chanpi", "Huachansu", or "Cinobufacini" through different electronic databases, including PubMed, Web of Science, Chinese National Knowledge Infrastructure (CNKI), the Wanfang Database, and Pharmacopoeia of China. In addition, Chinese medicine books from different times were used to elucidate the traditional uses of BGC. Electronic databases, including the "IUCN Red List of Threatened Species", "American Museum of Natural History" and "AmphibiaWeb Species Lists", were used to validate the scientific name of BGC.

RESULTS

To date, about 118 bufadienolide monomers and 11 indole alkaloids have been identified from BGC in total. The extracts and isolated compounds exhibit a wide range of in vitro and in vivo pharmacological effects. The literature search demonstrated that the ethnomedicinal uses of BGC, such as detoxification, anti-inflammation and the ability to reduce swelling and pain associated with infections, are correlated with its modern pharmacological activities, including antitumor, immunomodulation and attenuation of cancer-derived pain. Bufadienolides and indole alkaloids have been regarded as the main active substances in BGC, among which bufadienolides have significant antitumor activity. Furthermore, the cardiotoxicity of bufadienolides was discussed, and the main molecular mechanism involves in the inhibition of Na⁺/K⁺-ATPase. Besides, with the development of modern analytical techniques, the quality control methods of BGC-derived TCMs are being improved constantly.

CONCLUSIONS

An increasing number of reports suggest that BGC can be regarded as an excellent source for exploring the potential antitumor constituents. However, the future antitumor research of BGC needs to follow the standard pharmacology guidelines, so as to provide comprehensive pharmacological information and aid the reproducibility of the data. Besides, to ensure the efficacy and safety of BGC-derived TCMs, it is vital to construct a comprehensive quality evaluation model on the basis of clarifying pharmacodynamic-related and toxicity-related compositions.

Huachansu suppresses TRPV1 up-regulation and spinal astrocyte activation to prevent oxaliplatin-induced peripheral neuropathic pain in rats

Chemotherapy-induced peripheral neuropathic pain (CIPNP) is a major dose- and therapy-limiting side effect that is particularly difficult to treat. Huachansu, an aqueous extract from toad skin, is a widely used anti-cancer natural product in China. Clinical findings have established the safety and effectiveness of Huachansu in combination with chemotherapy to promote the therapeutic efficacy while alleviate the side effects, especially cancer-related pain symptoms. Unfortunately, experimental data on the effects and mechanisms of Huachansu in combination with chemotherapy is not available. In this study, the effects of Huachansu were tested in vivo on a rat model of oxaliplatin-induced CIPNP. The results show, a single injection of Huachansu 2.5 g/kg produced a short-term analgesic effect on pre-established oxaliplatin-induced CIPNP after 60 min, as indicated by decreased mechanical and thermal hypersensitivity in comparison to oxaliplatin-treated rats. Repeated doses of Huachansu, given during CIPNP induction, prevented the development of oxaliplatin-induced CIPNP. This prophylactic effect of Huachansu was associated with suppressed oxaliplatin-induced TRPV1 up-regulation in the dorsal root ganglia and spinal astrocyte activation. These findings reveal Huachansu therapeutic potential in treating and preventing CIPNP.

Cinobufacini protects against paclitaxel-induced peripheral neuropathic pain and suppresses TRPV1 up-regulation and spinal astrocyte activation in rats

Chemotherapy-induced peripheral neuropathic pain is a major limiting factor affecting cancer patients. No effective treatment is currently available. Cinobufacini, an aqueous extract from toad skin, is a widely used anti-cancer drug in China. Clinical evidence has demonstrated the safety and effectiveness of cinobufacini in combination with chemotherapy to promote the therapeutic efficacy while alleviating side effects, especially cancer-related pain symptoms. In this study, the effects of cinobufacini were investigated in a rat model of paclitaxel-induced peripheral neuropathic pain (PIPNP) to better understand and expand its clinical application. A single injection of cinobufacini (2.5 g/kg, i.p.) alleviated pre-established PIPNP, as indicated by decreased mechanical and thermal hypersensitivity compared with paclitaxel-treated rats. Repeated cinobufacini (1.25 and 2.5 g/kg, i.p.), given during the induction of PIPNP, prevented the establishment of paclitaxel-induced mechanical and thermal hypersensitivity. This preventative effect was associated with suppressed paclitaxel-induced TRPV1 up-regulation and spinal astrocyte activation, as well as decreased production of spinal TNF-α and IL-1β. These findings reveal cinobufacini as a therapeutic potential to treat and prevent paclitaxel-induced peripheral neuropathic pain.

The Development of Toad Toxins as Potential Therapeutic Agents

Toxins from toads have long been known to contain rich chemicals with great pharmaceutical potential. Recent studies have shown more than 100 such chemical components, including peptides, steroids, indole alkaloids, bufogargarizanines, organic acids, and others, in the parotoid and skins gland secretions from different species of toads. In traditional Chinese medicine (TCM), processed toad toxins have been used for treating various diseases for hundreds of years. Modern studies, including both experimental and clinical trials, have also revealed the molecular mechanisms that support the development of these components into medicines for the treatment of inflammatory diseases and cancers. More recently, there have been studies that demonstrated the therapeutic potential of toxins from other species of toads, such as Australian cane toads. Previous reviews mostly focused on the pharmaceutical effects of the whole extracts from parotoid glands or skins of toads. However, to fully understand the molecular basis of toad toxins in their use for therapy, a comprehensive understanding of the individual compound contained in toad toxins is necessary; thus, this paper seeks to review the recent studies of some typical compounds frequently identified in toad secretions.

Evaluation of Bufadienolides as the Main Antitumor Components in Cinobufacin Injection for Liver and Gastric Cancer Therapy

BACKGROUND

Cinobufacin injection, also known as huachansu, is a preparation form of Cinobufacini made from Cinobufacin extract liquid. Despite that Cinobufacin injection is shown to shrink liver and gastric tumors, improving patient survival and life quality, the effective components in Cinobufacin remain elusive. In this study, we aim to screen antitumor components from Cinobufacin injection to elucidate the most effective antitumor components for treatment of liver and gastric cancers.

MATERIALS AND METHODS

High performance liquid chromatography (HPLC) and LC-MS/MS analysis were used to separate and determine the components in Cinobufacin injection. Inhibition rates of various components in Cinobufacin injection on liver and gastric cancer cells were determined with MTT assay; Hepatocellular carcinoma and gastric cancer models were used to assess the antitumor effect of the compounds in vivo.

RESULTS

The major constituents in Cinobufacin injection include peptides, nucleic acids, tryptamines and bufotalins. MTT assay revealed that bufadienolides had the best antitumor activity, with peptides being the second most effective components. Bufadienolides showed significant inhibition rates on gastric and hepatocellular tumour growth in vivo.

CONCLUSION

Bufadienolides are the most effective components in Cinobufacini injection for the treatment of liver and gastric cancers. This discovery can greatly facilitate further research in improving the therapeutic effects of Cinobufacin injection, meanwhile reducing its adverse reaction.

Effects of active bufadienolide compounds on human cancer cells and CD4+CD25+Foxp3+ regulatory T cells in mitogen-activated human peripheral blood mononuclear cells

The growth inhibitory effects of bufadienolide compounds were investigated in two intractable cancer cells, a human glioblastoma cell line U-87 and a pancreatic cancer cell line SW1990. Among four bufadienolide compounds, a dose-dependent cytotoxicity was observed in these cancer cells after treatment with gamabufotalin and arenobufagin. The IC50 values of the two compounds were 3-5 times higher in normal peripheral blood mononuclear cells (PBMCs) than these values for both cancer cell lines. However, similar phenomena were not observed for two other bufadienolide compounds, telocinobufagin and bufalin. These results thus suggest that gamabufotalin and arenobufagin possess selective cytotoxic activity against tumor cells rather than normal cells. Moreover, a clear dose-dependent lactate dehydrogenase (LDH) release, a well-known hallmark of necrosis, was observed in both cancer cells treated with gamabufotalin, suggesting that gamabufotalin-mediated cell death is predominantly associated with a necrosis-like phenotype. Of most importance, treatment with as little as 8 ng/ml of gamabufotalin, even an almost non-toxic concentration to PBMCs, efficiently downregulated the percentages of CD4+CD25+Foxp3+ regulator T (Treg) cells in mitogen-activated PBMCs. Given that Treg cells play a critical role in tumor immunotolerance by suppressing antitumor immunity, these results suggest that gamabufotalin may serve as a promising candidate, as an adjuvant therapeutic agent by manipulating Treg cells to enhance the efficacy of conventional anticancer drugs and lessen their side-effects. These findings provide insights into the clinical application of gamabufotalin for cancer patients with glioblastoma/pancreatic cancer based on its cytocidal effect against tumor cells as well as its depletion of Treg cells.

Multi-constituent identification in Australian cane toad skin extracts using high-performance liquid chromatography high-resolution tandem mass spectrometry

Toad skins and venom glandular secretions have been widely used for centuries in traditional Chinese and Japanese medicine for the treatment of various ailments such as cancer, sores, toothache, local inflammation and pain. The active chemical constituents from traditional oriental medicines have demonstrated potential in the development of effective therapeutic pharmaceuticals. Our primary focus in this research was to identify and characterise 'active' compounds or groups of compounds for their potential as neuropsychiatric disorder therapeutics. For this aim, we utilised a variety of solvents, i.e., the aqueous, 60% ethanol (aqueous) and acetic acid (aq) (at two different pHs) for extractions of Australian cane toad skins to identify chemical constituents. The identification of compounds was carried out using HPLC-ESI-Q-TOF-MS/MS based on the accurate mass measurement for molecular ions and MS/MS analysis, whereby accurate mass pseudo-molecular ions and characteristic fragment ions were compared to published reference data, including mass bank and NIST. As a result, we have to date identified 42 major constituents including alkaloids, amino acids, bufadienolides, fatty acids, nucleobases, nucleosides and vitamins mostly from the aqueous and 60% ethanol extracts. Of the 42 constituents identified, 29 were found in the aqueous extract, 35 were found in the ethanol (aq) extract and only 10 in the pH 1.78 acetic acid extract and 11 in the pH 2.17 acetic acid extract of the cane toad skins. Therefore, the aqueous and 60% ethanolic extracts present the greatest potential for ongoing development in our assays. There have been no previous reports on the identification of many of the constituents we have here identified in Australian cane toad skins. These findings, while somewhat consistent with findings in toad skins in other countries, identifies the presence of potential bioactive constituents. Our results showed that HPLC-ESI-Q-TOF-MS/MS is an effective method to characterise and identify components in Australian cane toad skin extracts. Chemical profiling is an essential initial step in the identification and therapeutic exploitation of bioactive agents present in Australian cane toad skin extracts.

Characterization and quantitative amino acids analysis of analgesic peptides in cinobufacini injection by size exclusion chromatography, matrix-assisted laser desorption/ionization time of flight mass spectrometry and gas chromatography mass spectrometry

Cinobufacini injection that comes from the water extract of Bufo bufo gargarizans Cantor skin is widely used for cancer treatment in China. Peptide is one of its major types of constituents, however the biological effects and content of this injection are little reported. In present study, the analgesic effect of peptides was determined and evaluated by in-vivo models. To characterize and quantitatively analyze these peptides, a reliable and efficient method combining size exclusion chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with amino acid analysis was developed. The peptides presented as a series of analogs with similar molecular weights mostly ranging from 2 to 8 kDa. The amino acid analysis by gas chromatography mass spectrometry (GC-MS) was developed to determine both free and combined amino acids (FAA and CAA) in cinobufacini injection. This method achieved good linearity (R(2) , 0.9909-0.9999) and low limit of detection and quantification. FAA and CAA samples were efficiently analyzed by modified Phenomenex EZ: faast procedure. For the sample analysis, the method showed good repeatability (relative standard deviation, RSD ≤ 10%). For most FAA and CAA the mean recoveries were >80% with RSD <10%. The GC-MS based method is useful for quality assurance of both FAA and CAA in cinobufacini injection.

Toad glandular secretions and skin extractions as anti-inflammatory and anticancer agents

Toad glandular secretions and skin extractions contain many natural agents which may provide a unique resource for novel drug development. The dried secretion from the auricular and skin glands of Chinese toad (Bufo bufo gargarizans) is named Chansu, which has been used in Traditional Chinese Medicine (TCM) for treating infection and inflammation for hundreds of years. The sterilized hot water extraction of dried toad skin is named Huachansu (Cinobufacini) which was developed for treating hepatitis B virus (HBV) and several types of cancers. However, the mechanisms of action of Chansu, Huachansu, and their constituents within are not well reported. Existing studies have suggested that their anti-inflammation and anticancer potential were via targeting Nuclear Factor (NF)-κB and its signalling pathways which are crucial hallmarks of inflammation and cancer in various experimental models. Here, we review some current studies of Chansu, Huachansu, and their compounds in terms of their use as both anti-inflammatory and anticancer agents. We also explored the potential use of toad glandular secretions and skin extractions as alternate resources for treating human cancers in combinational therapies.