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

Effects of ciprofloxacin and levofloxacin on initial colonization of intestinal microbiota in Bufo gargarizans at embryonic stages

Ciprofloxacin (CIP) and levofloxacin (LEV) are broad-spectrum antibiotics with potent antibacterial activity. Although many studies have shown that antibiotics can lead to gut microbiota disruption, the effects of CIP and LEV on gut microbial colonization at the embryonic stage remain poorly characterized. Here, we evaluated the response of Bufo gargarizans embryos in terms of gut microbiota colonization, growth and developmental stages to CIP and LEV exposure. Embryos treated with 100 μg/L CIP and LEV exhibited significantly reduced diversity and richness of the gut microbiota, as well as altered community structure. Both CIP and LEV treatments resulted in an increase in the pathogenic bacteria Bosea and Aeromonas, and they appeared to be more resistant to CIP than LEV. Additionally, CIP exposure caused reduced total length and delayed the development in B. gargarizans embryos, while LEV increased the total length and promoted embryonic development. The present study revealed the adverse effects of CIP and LEV exposure on host gut microbiota, growth and development during the embryonic stage, and contributed new perspectives to the evaluation of early aquatic ecological risk under CIP and LEV exposure.

Preparation for oxidative stress in Chinese toads (Bufo gargarizans) living under natural conditions along an altitudinal gradient

Preparation for oxidative stress (POS) has been widely reported in animals under controlled laboratory conditions, but whether this phenomenon is visible in animals under natural conditions remains to be explored. Altitudinal gradients provide a good opportunity to address this question, since environmental conditions become more hostile with increasing altitude. Here, we investigated the levels of oxidative stress, oxidative damage, and antioxidant defenses in Chinese toads (Bufo gargarizans) along an altitudinal gradient (50 m, 1200 m, 2300 m, 3400 m above sea level). The results show that changing altitude led to a significantly lower ratio of oxidized to reduced glutathione in liver, with a higher value at 50 m. This ratio in muscle tissues did not differ significantly between altitudes of 50 m, 2300 m, and 3400 m. However, reduced glutathione content increased significantly along the altitude, with higher values in liver at 2300 m and higher values in skeletal muscle at 3400 m. Malondialdehyde (MDA) content in liver did not change significantly with increasing altitude. Brain and muscle tissues showed a higher MDA content at 50 m than the other three altitudes. The activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase, as well as total antioxidant capacity, also displayed tissue-specific upregulation in heart, skeletal muscle, and brain, but all of these antioxidant enzymes except for glutathione-S-transferase were significantly reduced in liver along the altitudinal gradient. In summary, environmental factors at higher altitude did not lead to higher levels of oxidative stress and oxidative damage in B. gargarizans, mainly due to stronger antioxidant defenses. This study corroborates the occurrence of POS in high-altitude toads living under field conditions and contributes to revealing the biochemical adaptations to extreme environments at higher altitude.

Cytochrome P450 Mining for Bufadienolide Diversification

Bufadienolides are a class of steroids with a distinctive α-pyrone ring at C17, mostly produced by toads and consisting of over 100 orthologues. They exhibit potent cardiotonic and antitumor activities and are active ingredients of the traditional Chinese medicine Chansu and Cinobufacini. Direct extraction from toads is costly, and chemical synthesis is difficult, limiting the accessibility of active bufadienolides with diverse modifications and trace content. In this work, based on the transcriptome and genome analyses, using a yeast-based screening platform, we obtained eight cytochrome P450 (CYP) enzymes from toads, which catalyze the hydroxylation of bufalin and resibufogenin at different sites. Moreover, a reported fungal CYP enzyme Sth10 was found functioning in the modification of bufalin and resibufogenin at multiple sites. A total of 15 bufadienolides were produced and structurally identified, of which six were first discovered. All of the compounds were effective in inhibiting the proliferation of tumor cells, especially 19-hydroxy-bufalin (2) and 1β-hydroxy-bufalin (3), which were generated from bufalin hydroxylation catalyzed by CYP46A35. The catalytic efficiency of CYP46A35 was improved about six times and its substrate diversity was expanded to progesterone and testosterone, the common precursors for steroid drugs, achieving their efficient and site-specific hydroxylation. These findings elucidate the key modification process in the synthesis of bufadienolides by toads and provide an effective way for the synthesis of unavailable bufadienolides with site-specific modification and active potentials.

Animal-derived natural products for hepatocellular carcinoma therapy: current evidence and future perspectives

Hepatocellular carcinoma (HCC) has a high morbidity and mortality rate, and the survival rate of HCC patients remains low. Animal medicines have been used as potential therapeutic tools throughout the long history due to their different structures of biologically active substances with high affinity to the human body. Here, we focus on the effects and the mechanism of action of animal-derived natural products against HCC, which were searched in databases encompassing Web of Science, PubMed, Embase, Science Direct, Springer Link, and EBSCO. A total of 24 natural products from 12 animals were summarized. Our study found that these natural products have potent anti-hepatocellular carcinoma effects. The mechanism of action involving apoptosis induction, autophagy induction, anti-proliferation, anti-migration, and anti-drug resistance via phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR), Ras/extracellular signal regulated kinases (ERK)/mitogen-activated protein kinase (MAPK), Wnt/β-catenin, and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathways. Huachansu injection and sodium cantharidate have been used in clinical applications with good efficacy. We review the potential of animal-derived natural products and their derivatives in the treatment of HCC to date and summarize their application prospect and toxic side effects, hoping to provide a reference for drug development for HCC.

Chemical Composition, Pharmacological Effects and Clinical Applications of Cinobufacini

Chinese medicine cinobufacini is an extract from the dried skin of Bufo bufo gargarizans Cantor, with active ingredients of bufadienolides and indole alkaloids. With further research and clinical applications, it is found that cinobufacini alone or in combination with other therapeutic methods can play an anti-tumor role by controlling proliferation of tumor cells, promoting apoptosis, inhibiting formation of tumor neovascularization, reversing multidrug resistance, and regulating immune response; it also has the functions of relieving cancer pain and regulating immune function. In this paper, the chemical composition, pharmacological effects, clinical applications, and adverse reactions of cinobufacini are summarized. However, the extraction of monomer components of cinobufacini, the relationship between different mechanisms, and the causes of adverse reactions need to be further studied. Also, high-quality clinical studies should be conducted.

Synthesis of Bufadienolide Cinobufagin via Late-Stage Singlet Oxygen Oxidation/Rearrangement Approach

This manuscript describes a concise synthesis of cinobufagin, a natural steroid of the bufadienolide family, from readily available dehydroepiandrosterone (DHEA), as well as its α5-epimer derived from 3-epi-andosterone. This synthesis features expedient installation of the 17β-pyrone moiety with the 14β,15β-epoxide and the 16β-acetoxy group using a photochemical regioselective singlet oxygen [4 + 2] cycloaddition followed by CoTPP-promoted in situ endoperoxide rearrangement to provide a 14β,16β-bis-epoxide in 64% yield with a 1.6:1 d.r. This β,β-bis-epoxide intermediate was subsequently subjected to a regioselective scandium(III) trifluoromethanesulfonate catalyzed House-Meinwald rearrangement to establish the 17β-configuration. The synthesis of cinobufagin is achieved in 12 steps (LLS) and 7.6% overall yield, and we demonstrate that it could be used as a platform for the subsequent medicinal chemistry exploration of cinobufagin analogs such as cinobufagin 5α-epimer.

Efficacy and Safety of Hepatic Arterial Infusion Therapy with Cinobufacini in Advanced Hepatocellular Carcinoma with Macrovascular Invasion: A Retrospective Cohort Study

Background

The presence of macrovascular invasion (MVI) is associated with poor prognosis in advanced hepatocellular carcinoma (HCC). This study aims to evaluate the efficacy and safety of Cinobufacini therapy via hepatic arterial infusion (HAI) in advanced HCC patients with MVI.

Methods

The clinical records of 130 consecutive patients with unresectable advanced HCC and MVI who had received Cinobufacini or cisplatin plus 5-fluorouracil (CF) treatment via HAI were retrospectively analyzed. The therapeutic efficacy, overall survival (OS), progression-free survival (PFS), and adverse events were compared between the two treatment groups.

Results

The Cinobufacini group demonstrated significant curative effects on treatment via HAI compared with the CF group, including the objective response rate (44.9% vs 27.9%, P=0.048), the median OS (14.8 months vs 11.1 months, P=0.010), and the median PFS (10.3 months vs 6.0 months, P=0.006). Result in subgroup analysis of portal vein invasion grade supported the efficacy in Cinobufacini treatment, especially in the median OS of Vp1-2 (18.3 months vs 14.3 months, P=0.043) and Vp3 (15.0 months vs 11.4 months, P=0.046), as well as the median PFS of Vp1-2 (14.8 months vs 10.2 months, P=0.028) and Vp3 (10.8 months vs 6.6 months, P=0.033) compared with CF treatment. Cox proportional hazards model and forest plot analysis of factors confirmed the survival benefit from HAI with Cinobufacini over CF (hazard ratio [HR], 0.61; 95% CI: 0.40-0.91; P=0.010). Multivariable analysis identified portal vein invasion grade (Vp4; HR, 1.78; 95% CI: 1.03-2.16; P=0.032) and AFP (>1000; HR, 1.61; 95% CI: 1.08-1.91; P=0.039) as the independent factors for prognosis. Moreover, the total incidence of adverse events in the Cinobufacini group was significantly lower than in the CF group (60.9% vs 82.0%, P=0.009).

Conclusion

Cinobufacini therapy via HAI is a viable strategy for curing advanced HCC with MVI, due to prolonged survival and a superior safety profile.

3α-Hydroxybufadienolides in Bufo gallbladders: structural insights and biotransformation

Bufadienolides, naturally occurring steroids primarily found in toads, have garnered attention for their pharmacological properties and ecological significance. In this study, we isolated and identified 21 bufadienolides from the gallbladders of Bufo gargarizans, comprising four new compounds and 17 known ones. Notably, the predominance of 15 bufadienolides with a 3α-OH configuration in toad bile differs significantly from the 3β-OH bufadienolides found in venom secreted by toad glands. Moreover, our investigation into the biotransformation of 3β-OH and 3α-OH bufadienolides in the liver and kidney tissues of toads revealed an irreversible conversion from 3β-OH to 3α-OH bufadienolides, suggesting a crucial role in toad self-detoxification. These findings provide valuable insights into the structural diversity of bufadienolides and advance our understanding of their medical and ecological significance.

A UPLC-QTOF/MS-based hepatic tissue metabolomics approach deciphers the mechanism of Huachansu tablets-based intervention against hepatocellular carcinoma

Huachansu (HCS) tablets, classified as well-known traditional Chinese medicine (TCM) preparation, have been proved to be effective in the treatment of hepatocellular carcinoma (HCC) in clinical studies. However, the underlying mechanism of HCS tablets against HCC has not been comprehensively elucidated. In this study, a rat model of HCC was established with diethylnitrosamine (DEN) inducer. The efficacy of HCS tablets against HCC was assessed through liver histopathological examination and evaluation of biochemical indicators. A metabolomics method based on UPLC-Q-TOF/MS combined with multivariate data analysis was established to identify differential metabolites related to the inhibition effect of HCS tablets on HCC, and then the relevant metabolic pathway analysis was performed to investigate the anti-HCC mechanisms of HCS tablets. The results showed that compared to the control group, the HCC model group showed a significant increase in the values of HCC-related biochemical indicators and the number of tumor nodules, indicating the successful establishment of the HCC rat model. Upon treatment with HCS tablets, the values of HCC-related biochemical indicators decreased, liver fibrosis and nuclear deformation were also significantly alleviated. A total of 15 differential metabolites associated with the anti-tumor effect of HCS tablets on HCC were screened and annotated through hepatic tissue metabolomics studies. Analysis of metabolic pathways revealed that the therapeutic effects of HCS tablets on HCC mainly involved the pentose and glucuronate interconversions and arachidonic acid metabolism. Further western blotting corroborated that the alteration in arachidonic acid (AA) level after the intervention of HCS tablets was related to the inhibition of cPLA2α expression in rat liver tissues. In conclusion, HCS tablets exhibit a certain anti-tumor effect on HCC, and the metabolomics method based on UPLC-Q-TOF/MS combined with further verification at the biochemical level is a promising way to reveal its underlying mechanism.

Clinical efficacy and safety of Chinese herbal injections in combination with platinum-based chemotherapy for advanced non-small cell lung cancer: a systematic review and meta-analysis of 140 randomized controlled trials

Background and aim

Chinese herbal injection (CHI) is a widely used preparation for advanced non-small cell lung cancer (NSCLC) treatment to alleviate the adverse drug reactions and enhance the clinical efficacy of chemotherapy. However, its efficacy and safety in combination with platinum-based chemotherapy (PBC) remain poorly understood owing to the lack of high-level evidence in the face of a wide variety of CHIs. Therefore, in this study, we aimed to explore the efficacy and safety of CHIs in combination with PBC regimens in the treatment of mid- and advanced NSCLC.

Methods

Systematic evaluation and meta-analysis were conducted as per the Preferred Reporting Project for Systematic Evaluation and Meta-Analysis Protocols (PRISMA-P). Seven databases were comprehensively searched for relevant randomized controlled trials (RCTs) through August 1, 2022. The quality of each study was evaluated based on the Cochrane Handbook for Systematic Reviews of Interventions. Statistical analysis was performed using Revman 5.3, with dichotomies expressed as risk ratio (RR) and 95% confidence interval (CI). Objective response rate (ORR) and disease control rate (DCR) were selected as the primary outcomes, with quality of life (QoL) and toxic side effects as secondary outcomes.

Results

A total of 140 RCTs were included in this study. The results of the meta-analysis suggested that, compared with PBC alone, PBC combined with CHIs significantly improved the ORR (RR=1.35, 95% CI: 1.30-1.41, P<0.001), DCR (RR=1.15, 95% CI: 1.13-1.18, P<0.001) and QoL (RR=1.29, 95% CI: 1.24-1.33, P<0.001). Moreover, the combination treatment reduced chemotherapy-induced leukopenia (RR=0.69, 95% CI: 0.64-0.75, P<0.001), anemia (RR=0.70, 95% CI: 0.62-0.79, P<0.001), thrombocytopenia (RR=0.68, 95% CI: 0.62-0.75, P<0.001), nausea and vomiting (RR=0.69, 95% CI: 0.63-0.76, P<0.001), diarrhea (RR=0.59, 95% CI: 0.48-0.73, P<0.001), and constipation (RR=0.68, 95% CI: 0.54-0.86, P=0.001).

Conclusion

According to the available evidence, CHIs in combination with PBC can improve clinical efficacy and reduce the toxic side effects in the treatment of advanced NSCLC. However, considering the study's limitations, more rigorous and high-quality studies are needed to further confirm the results.

Systematic review registration

https://inplasy.com/inplasy-2022-1-0104/, identifier INPLASY202210104.

Hellebrigenin triggers death of promyelocytic leukemia cells by non-genotoxic ways

Bufadienolides are digitalis-like aglycones mainly found in skin secretions of toads. Among their biological properties, the mechanisms of antiproliferative action on tumor cells remain unclear for many compounds, including against leukemia cells. Herein, it was evaluated the mechanisms involved in the antiproliferative and genotoxic actions of hellebrigenin on tumor cell lines and in silico capacity to inhibit the human topoisomerase IIa enzyme. Firstly, its cytotoxic action was investigated by colorimetric assays in human tumor and peripheral blood mononuclear cells (PBMC). Next, biochemical and morphological studies were detailed by light microscopy (trypan blue dye exclusion), immunocytochemistry (BrdU uptake), flow cytometry and DNA/chromosomal damages (Cometa and aberrations). Finally, computational modelling was used to search for topoisomerase inhibition. Hellebrigenin reduced proliferation, BrdU incorporation, viability, and membrane integrity of HL-60 leukemia cells. Additionally, it increased G2/M arrest, internucleosomal DNA fragmentation, mitochondrial depolarization, and phosphatidylserine externalization in a concentration-dependent manner. In contrast to doxorubicin, hellebrigenin did not cause DNA strand breaks in HL-60 cell line and lymphocytes, and it interacts with ATPase domain residues of human topoisomerase IIa, generating a complex of hydrophobic and van der Waals interactions and hydrogen bonds. So, hellebrigenin presented potent anti-leukemic activity at concentrations as low as 0.06 μM, a value comparable to the clinical anticancer agent doxorubicin, and caused biochemical changes suggestive of apoptosis without genotoxic/clastogenic-related action, but it probably triggers catalytic inhibition of topoisomerase II. These findings also emphasize toad steroid toxins as promising lead antineoplasic compounds with relatively low cytotoxic action on human normal cells.

Bufogarlides A-C, three new bufadienolides with Δ14,15 double bond from the skins of Bufo bufo gargarizans

Three new bufadienolides with a Δ14,15 double bond, named bufogarlides A-C (1-3), together with three known analogs (4-6), were isolated from the skins of Bufo bufo gargarizans. Their structures were identified by analyses of spectroscopic data (1 D and 2 D NMR, HR-ESIMS), and comparison with the literature data. All the isolates were evaluated for their cytotoxic activities against ovarian carcinoma cell lines A2780 and SKOV3. Among them, compound 5 showed the highest potential for the growth inhibition of cancerous cells A2780 and SKOV3 with the IC50 values of 21.09 and 67.08 nM, respectively.

Efficacy and safety of Huachansu combined with adjuvant chemotherapy in resected colorectal cancer patients: a prospective, open-label, randomized phase II study

Although some studies in China have suggested Huachansu (HCS) combined with chemotherapy is effective in the treatment of various cancers, there are few studies on colorectal cancer (CRC), especially in postoperative adjuvant chemotherapy. The aim of this study was to test the hypothesis that HCS combined with adjuvant chemotherapy would improve survival probability in resected CRC patients. This was a prospective, open-label, randomized phase II study. Patients with stage III or high-risk stage II resected CRC were randomly assigned to the chemotherapy and HCS + chemotherapy groups. The Chemotherapy group was treated with the FOLFOX regimen for ≥ 6 cycles or the CAPEOX regimen for ≥ 4 cycles. The HCS + chemotherapy group was treated with HCS on the basis of the chemotherapy group. The primary endpoint was 3-year disease-free survival (DFS), and the secondary endpoints were 3-year overall survival (OS) and toxicity. A total of 250 patients were included in this study (126 chemotherapy, 124 HCS + chemotherapy). There were significant differences in 3-year DFS between the two groups (median 28.7 vs. 31.6 months, respectively; P = 0.027), but no significant differences in 3-year OS between the two groups (median 32.7 vs. 34 months, respectively; P = 0.146). No patients experienced grade four adverse events, and the rates of leukopenia, neutropenia, and diarrhea in the HCS + chemotherapy group were lower than that those in the chemotherapy group. HCS combined with adjuvant chemotherapy after radical resection for patients with stage III or high-risk stage II CRC was demonstrated to be an effective and feasible treatment.

Bufotalin Suppresses Proliferation and Metastasis of Triple-Negative Breast Cancer Cells by Promoting Apoptosis and Inhibiting the STAT3/EMT Axis

Triple-negative breast cancer (TNBC) is a highly aggressive type of breast cancer and has a poor prognosis. As standardized TNBC treatment regimens cause drug resistance and tumor recurrence, the development of new TNBC treatment strategies is urgently required. Bufotalin is a bufadienolide isolated from the skin and parotid venom glands of the toad Bufo gargarizan, and has several pharmacological properties, including antiviral, anti-inflammatory, and anticancer activities. However, the anticancer effect and underlying molecular mechanisms of action of bufotalin in TNBC have not been fully studied. In the current study, we investigated the effects of bufotalin on the growth and metastasis of MDA-MB-231 and HCC1937 TNBC cells. Bufotalin potently inhibited the proliferation of both TNBC cell lines by promoting cell cycle arrest and caspase-mediated apoptosis. Furthermore, bufotalin effectively suppressed the migration and invasion of both TNBC cell lines by regulating the expression of key epithelial-mesenchymal transition (EMT) biomarkers, matrix metalloproteinases (MMPs), and integrin α6. Notably, the anticancer effect of bufotalin in TNBC cells was associated with the downregulation of the signal transducer and activator of the transcription 3 (STAT3) signaling pathway. Collectively, our results suggest that the natural compound bufotalin may exert antiproliferative and antimetastatic activities in TNBC cells by modulating the apoptotic pathway and the STAT3/EMT axis.

Regulation mechanisms underlying tail resorption in Bufo gargarizans metamorphosis

Anurans have been excellent organisms for studying amphibian metamorphosis. Tail resorption is a remarkable event that occurs during amphibian metamorphosis. Although tail resorption has been previously studied in other anurans like Xenopus laevis and Rana chensinensis, there is no report on Bufo gargarizans. This paper thus explored the mechanism of tail resorption during metamorphosis in Bufo gargarizans tadpoles through some biological research methods. Histological results showed that the tail tissues of tadpoles gradually degraded as metamorphosis progressed. RNA sequencing analysis was performed to examine the expression level and functional enrichment of differentially expressed genes in the tail. In addition, we analyzed the mRNA expression levels of genes related to tail resorption by quantitative real-time polymerase chain reaction. We also speculated on three pathways that participate in the regulation of tail resorption based on the above results. The present study might provide a theoretical basis and novel insights for further research of complex molecular mechanisms of tail resorption in amphibians.

Review on Processing Methods of Toxic Chinese Materia Medica and the Related Mechanisms of Action

Toxic Chinese materia medica (CMM) has both pharmacological activities and toxic effects. Based on thousands of years of experience in the application of CMMs, people have explored many practical processing methods of CMMs, also known as "Pao Zhi", to reduce/control toxicity and preserve/enhance efficacy. Toxic CMMs have been used throughout China's hospitals. Yet, the production and use of toxic CMM should be carried out in accordance with the Chinese pharmacopoeia (ChP) and the processing regulations formulated by the health administrative departments of provinces, autonomous regions, and municipalities directly under the Central Government. This paper summarizes the current understanding and awareness of toxicity and 45 toxic CMMs, the commonly used processing methods of toxic CMMs recorded in the 2020 edition of ChP, and the changes in the chemical component, toxicity, or efficacy profiles after processing. This review may provide useful information for the processing methods of toxic CMMs worldwide. We believe that with an in-depth study and understanding of toxic CMMs combined with a standardized application, the toxicity of CMMs will be predictable and controllable in the future.

Proteins from toad's parotoid macroglands: do they play a role in gland functioning and chemical defence?

BACKGROUND

Parotoid gland secretion of bufonid toads is a rich source of toxic molecules that are used against predators, parasites and pathogens. Bufadienolides and biogenic amines are the principal compounds responsible for toxicity of parotoid secretion. Many toxicological and pharmacological analyses of parotoid secretions have been performed, but little is known about the processes related to poison production and secretion. Therefore, our aim was to investigate protein content in parotoids of the common toad, Bufo bufo, to understand the processes that regulate synthesis and excretion of toxins as well as functioning of parotoid macroglands.

RESULTS

Applying a proteomic approach we identified 162 proteins in the extract from toad's parotoids that were classified into 11 categories of biological functions. One-third (34.6%) of the identified molecules, including acyl-CoA-binding protein, actin, catalase, calmodulin, and enolases, were involved in cell metabolism. We found many proteins related to cell division and cell cycle regulation (12.0%; e.g. histone and tubulin), cell structure maintenance (8.4%; e.g. thymosin beta-4, tubulin), intra- and extracellular transport (8.4%), cell aging and apoptosis (7.3%; e.g. catalase and pyruvate kinase) as well as immune (7.0%; e.g. interleukin-24 and UV excision repair protein) and stress (6.3%; including heat shock proteins, peroxiredoxin-6 and superoxide dismutase) response. We also identified two proteins, phosphomevalonate kinase and isopentenyl-diphosphate delta-isomerase 1, that are involved in synthesis of cholesterol which is a precursor for bufadienolides biosynthesis. STRING protein-protein interaction network predicted for identified proteins showed that most proteins are related to metabolic processes, particularly glycolysis, stress response and DNA repair and replication. The results of GO enrichment and KEGG analyses are also consistent with these findings.

CONCLUSION

This finding indicates that cholesterol may be synthesized in parotoids, and not only in the liver from which is then transferred through the bloodstream to the parotoid macroglands. Presence of proteins that regulate cell cycle, cell division, aging and apoptosis may indicate a high epithelial cell turnover in parotoids. Proteins protecting skin cells from DNA damage may help to minimize the harmful effects of UV radiation. Thus, our work extends our knowledge with new and important functions of parotoids, major glands involved in the bufonid chemical defence.

Identification of Protein Quality Markers in Toad Venom from Bufo gargarizans

Toad venom is a traditional Chinese medicine with high medicinal value. The existing quality evaluation standards of toad venom have obvious limitations because of the lack of research on proteins. Thus, it is necessary to screen suitable quality markers and establish appropriate quality evaluation methods for toad venom proteins to guarantee their safety and efficacy in clinical applications. SDS-PAGE, HPLC, and cytotoxicity assays were used to analyze differences in protein components of toad venom from different areas. Functional proteins were screened as potential quality markers by proteomic and bioinformatic analyses. The protein components and small molecular components of toad venom were not correlated in content. Additionally, the protein component had strong cytotoxicity. Proteomics analysis showed that 13 antimicrobial proteins, four anti-inflammatory and analgesic proteins, and 20 antitumor proteins were differentially expressed extracellular proteins. A candidate list of functional proteins was coded as potential quality markers. Moreover, Lysozyme C-1, which has antimicrobial activity, and Neuropeptide B (NPB), which has anti-inflammatory and analgesic activity, were identified as potential quality markers for toad venom proteins. Quality markers can be used as the basis of quality studies of toad venom proteins and help to construct and improve safe, scientific, and comprehensive quality evaluation methods.

Bufalin reverses ABCB1-mediated resistance to docetaxel in breast cancer

Background

Docetaxel (DCT) is widely used in clinical practice, but the drug resistance of breast cancer patients has become an important reason to limit its clinical efficacy. Chan'su is a commonly used traditional Chinese medicine for the treatment of breast cancer. Bufalin (BUF) is a bioactive polyhydroxy steroid extracted from chan'su and has strong antitumor activity, but there are few studies on reversing drug resistance in breast cancer. The aim of this study is to determine whether BUF can reverse the drug resistance to DCT and restore efficacy in breast cancer.

Methodology

The reversal index of BUF was detected by Cell Counting Kit-8 (CCK-8) assays. The effects of BUF on enhancing the apoptosis of DCT were detected by flow cytometry and Western Blot (WB), and the main differential expression levels of sensitive and resistant strains were detected by high-throughput sequencing. Rhodamine 123 assay, WB and ATP Binding Cassette Subfamily B Member 1 (ABCB1) ATPase activity experiments were used to detect the effect of BUF on ABCB1. The nude mouse orthotopic model was constructed to investigate the reversal effect of BUF on DCT resistance in vivo.

Results

With BUF intervention, the sensitivity of drug-resistant cell lines to DCT was increased. BUF can inhibit the expression of ABCB1 protein, increase the drug accumulation of DCT in drug-resistant strains, and reduce the ATPase activity of ABCB1. Animal experiments show that BUF can inhibit the growth of drug-resistant tumors in an orthotopic model of breast cancer and decrease the expression of ABCB1.

Conclusion

BUF can reverse ABCB1-mediated docetaxel resistance in breast cancer.

Bufadienolides from the Bufo viridis toad venom exert cytotoxic effects on cancer cells by inducing cell apoptosis and cell cycle arrest

A series of bufadienolides were isolated from the Bufo viridis toad venom, and their cytotoxic activities against three human cancer cell lines (HeLa, HT-29, MCF7) and a non-cancer cell line (L-O2) were explored using the MTT assay in vitro. All of nine compounds exhibited cytotoxic activities against the three cancer cell lines, with compound D4 exhibiting potent cytotoxic activity against HeLa cells and was better than positive control. Herein, we further evaluated the effect of compound D4 on HeLa cells. The results revealed that compound D4 has excellent cytotoxic effect on HeLa cells by inhibiting cell colony formation and migration, promoting cell apoptosis, increasing reactive oxygen species (ROS) levels and arresting of HeLa cells in S and G2/M phases. These findings encourage further work on the chemistry and bioactivity of the Bufo viridis toad venom.

Bufadienolides originated from toad source and their anti-inflammatory activity

Bufadienolide, an essential member of the C-24 steroid family, is characterized by an α-pyrone positioned at C-17. As the predominantly active constituent in traditional Chinese medicine of Chansu, bufadienolide has been prescribed in the treatment of numerous ailments. It is a specifically potent inhibitor of Na+/K+ ATPase with excellent anti-inflammatory activity. However, the severe side effects triggered by unbiased inhibition of the whole-body cells distributed α1-subtype of Na+/K+ ATPase, restrict its future applicability. Thus, researchers have paved the road for the structural alteration of desirable bufadienolide derivatives with minimal adverse effects via biotransformation. In this review, we give priority to the present evidence for structural diversity, MS fragmentation principles, anti-inflammatory efficacy, and structure modification of bufadienolides derived from toads to offer a scientific foundation for future in-depth investigations and views.

A research update on the antitumor effects of active components of Chinese medicine ChanSu

Clinical data show that the incidence and mortality rates of cancer are rising continuously, and cancer has become an ongoing public health challenge worldwide. Excitingly, the extensive clinical application of traditional Chinese medicine may suggest a new direction to combat cancer, and the therapeutic effects of active ingredients from Chinese herbal medicine on cancer are now being widely studied in the medical community. As a traditional anticancer Chinese medicine, ChanSu has been clinically applied since the 1980s and has achieved excellent antitumor efficacy. Meanwhile, the ChanSu active components (e.g., telocinobufagin, bufotalin, bufalin, cinobufotalin, and cinobufagin) exert great antitumor activity in many cancers, such as breast cancer, colorectal cancer, hepatocellular carcinoma and esophageal squamous cell carcinoma. Many pharmaceutical scientists have investigated the anticancer mechanisms of ChanSu or the ChanSu active components and obtained certain research progress. This article reviews the research progress and antitumor mechanisms of ChanSu active components and proposes that multiple active components of ChanSu may be potential anticancer drugs.

Cultural and Medicinal Use of Amphibians and Reptiles by Indigenous People in Punjab, Pakistan with Comments on Conservation Implications for Herpetofauna

Simple Summary

Humans have interacted with reptile and amphibian species for millennia. The current study was designed to collect knowledge about the use of amphibian and reptile species by the native peoples residing along the Jhelum and Chenab rivers in Punjab, Pakistan. To the best of our knowledge, this is the first quantitative assessment of the cultural uses of amphibian and reptile species in the study area. However, hunting, trade, and cultural use are the greatest threats to the diversity of the amphibians and reptiles in the studied area. These threats can potentially lead to their extinction. It is important to protect the highly endangered and vulnerable species employed in therapeutic medications, more specifically in terms of their conservation.

Abstract

Amphibians and reptiles have interacted with humans for millennia. However, humans interact with amphibian and reptile species in different manners, which depend on their culture and traditions. This study was designed to better understand the interactions between amphibian and reptile species and their usage among the native peoples in the vicinity of the Jhelum and Chenab rivers, Pakistan. Information was collected through semi-structured interviews and questionnaires, and was analyzed by using different indices, including the frequency of citation, corrected fidelity level, fidelity level, relative importance level, and informant major ailment. Two amphibians and twenty-six reptile species were used in therapeutic medicine in the study area. Based on the cultural analysis, we found that Naja naja (black cobra) was highly cited across all cultural groups. A 100% Fidelity Level was calculated for the following species: Naja naja (eye infection), Varanus bengalensis (joint pain), Eurylepis taeniolatus (cataract), and Acanthodactylus cantoris (cancer). We found five endangered species in the study area, i.e., Aspideretes gangeticus, A. hurum, Chitra indica, Varanus flavescens, and Geoclemys hamiltonii, that were used to cure joint pain, muscle stretching and pain, backbone pain, paralysis, and psoriasis, respectively. Likewise, Lissemys punctata andersoni, a vulnerable species as labelled by the International Union for Conservation of Nature, was extensively used for the treatment of joint pain, body pain, paralysis, and arthritis in the study area. In terms of conservation, it is critical to protect the highly vulnerable and endangered species that are being used in therapeutic medicines. Our findings may be helpful for the conservation of amphibian and reptile species by helping to make an effective plan to prevent their extinction. The main threats to the diversity of amphibian and reptile species in the area are hunting, trading, and cultural use. These threats could potentially lead to the extinction of these species. Therefore, with the involvement of concerned authorities, e.g., local stakeholders, the Ministry of Climate Change, provincial wildlife departments, academia, and conservation managers, immediate conservation measures should be taken for the protection and sustainable utilization of medicinal species.

Histological Study of Glandular Variability in the Skin of the Natterjack Toad—Epidalea calamita (Laurenti, 1768)—Used in Spanish Historical Ethnoveterinary Medicine and Ethnomedicine

Simple Summary

Common toads, including the natterjack toad (Epidalea calamita), have been used since ancient times for remedies, and thus constitute excellent biological material for pharmacological and natural product research. After a previous analysis of the historical-folk therapeutic use of amphibians in Spain, a histological study was carried out to provide a complementary ethnopharmacological view through the analysis of the integumentary heterogeneity of the serous (venom) and mucous glands from two adult specimens. Plastic-embedded semi-thin sections showed that serous/venom glands are cytologically homogeneous in spite of their genetic and biochemical complexity, leading to a cocktail that remains stored until extrusion. On the contrary, mucous glands, working continuously, show a more complex cytological variation and regional heterogeneity, which suggests an adaptive variability, leading to an invisible topographic map of skin toxicity. Natterjack toad-based folk remedies are usually extracted from the whole animal as a therapeutic unit in ethnoveterinary practice. However, a new ethnopharmacological vision could emerge from the study of tegumentary regional variation.

Abstract

Common toads have been used since ancient times for remedies and thus constitute excellent biological material for pharmacological and natural product research. According to the results of a previous analysis of the therapeutic use of amphibians in Spain, we decided to carry out a histological study that provides a complementary view of their ethnopharmacology, through the natterjack toad (Epidalea calamita). This species possesses a characteristic integument, where the parotoid glands stand out, and it has been used in different ethnoveterinary and ethnomedical practices. This histological study of their glandular variability allow us to understand the stages through which the animal synthesises and stores a heterogeneous glandular content according to the areas of the body and the functional moment of the glands. To study tegumentary cytology, a high-resolution, plastic embedding, semi-thin (1 micron) section method was applied. Up to 20 skin patches sampled from the dorsal and ventral sides were processed from the two adult specimens collected, which were roadkill. Serous/venom glands display a genetic and biochemical complexity, leading to a cocktail that remains stored (and perhaps changes over time) until extrusion, but mucous glands, working continuously to produce a surface protection layer, also produce a set of active protein (and other) substances that dissolve into mucous material, making a biologically active covering. This study provides a better understanding of the use of traditional remedies in ethnoveterinary medicine.

Role of Traditional Chinese Medicine in Treating Severe or Critical COVID-19: A Systematic Review of Randomized Controlled Trials and Observational Studies

Background: The coronavirus disease 2019 (COVID-19) continues to spread globally. Due to the higher risk of mortality, the treatment of severe or critical patients is a top priority. Traditional Chinese medicine (TCM) treatment has played an extremely important role in the fight against COVID-19 in China; a timely evidence summary on TCM in managing COVID-19 is crucial to update the knowledge of healthcare for better clinical management of COVID-19. This study aimed to assess the effects and safety of TCM treatments for severe/critical COVID-19 patients by systematically collecting and synthesizing evidence from randomized controlled trials (RCTs) and observational studies (e.g., cohort).

Methods: We searched nine databases up to 19th March 2022 and the reference lists of relevant publications. Pairs of reviewers independently screened studies, extracted data of interest, and assessed risk of bias. We performed qualitative systematic analysis with visual presentation of results and compared the direction and distribution of effect estimates for each patient’s important outcome. We performed sensitivity analyses to observe the robustness of results by restricting analysis to studies with low risk of bias.

Results: The search yielded 217,761 records, and 21 studies (6 RCTs and 15 observational studies) proved eligible. A total of 21 studies enrolled 12,981 severe/critical COVID-19 patients with a mean age of 57.21 years and a mean proportion of men of 47.91%. Compared with usual supportive treatments, the effect estimates of TCM treatments were consistent in direction, illustrating that TCM treatments could reduce the risk of mortality, rate of conversion to critical cases, and mechanical ventilation, and showed significant advantages in shortening the length of hospital stay, time to viral clearance, and symptom resolution. The results were similar when we restricted analyses to low-risk-bias studies. No serious adverse events were reported with TCM treatments, and no significant differences were observed between groups.

Conclusion: Encouraging evidence suggests that TCM presents substantial advantages in treating severe/critical COVID-19 patients. TCM has a safety profile that is comparable to that of conventional treatment alone. TCMs have played an important role in China’s prevention and treatment of COVID-19, which sets an example of using traditional medicine in preventing and treating COVID-19 worldwide.

Cinobufagin inhibits proliferation of acute myeloid leukaemia cells by repressing c-Myc pathway-associated genes

Cinobufagin is a cardiotoxic bufanolide steroid secreted by the Asiatic toad, Bufo gargarizans. Bufanolides inhibit Na⁺/K⁺ ATPase and have similar effects as cardiac glycosides, such as digitoxin or ouabain derived from toxic herbs. Recently, the anti-cancer effects of bufanolides have gained attention, however the underlying molecular mechanisms remain unclear. Selecting cinobufagin as a candidate anti-leukaemia agent, we here conducted transcriptomic analyses on the effect of cinobufagin on human acute myeloid leukaemia (AML) cell lines, HL60 and Kasumi-1. Flow cytometry analysis showed that cinobufagin induced apoptosis in both cell lines. RNA-sequencing (RNA-seq) of the two cell lines treated with cinobufagin revealed commonly downregulated genes with enrichment in the term "Myc active pathway" according to Gene Ontology (GO) analysis. Gene Set Enrichment Analysis (GSEA) of genes downregulated by cinobufagin also showed "MYC_TARGETS_V2" with the highest normalised enrichment score (NES) in both cell lines. In contrast, hallmarks such as "TNFA_SIGNALING_VIA_NFKB", "APOPTOSIS", and "TGF_BETA_SIGNALING" were significantly enriched as upregulated gene sets. Epigenetic analysis using chromatin immunoprecipitation and sequencing (ChIP-seq) confirmed that genes encoding cell death-related signalling molecules were upregulated by gain of H3K27ac, whereas downregulation of c-Myc-related genes was not accompanied by H3K27ac alteration. Cinobufagin is an anti-proliferative natural compound with c-Myc-inhibiting and epigenetic-modulating activity in acute myeloid leukaemia.

A review of chemical defense in harlequin toads (Bufonidae: Atelopus)

Toads of the genus Atelopus are chemically defended by a unique combination of endogenously synthesized cardiotoxins (bufadienolides) and neurotoxins which may be sequestered (guanidinium alkaloids). Investigation into Atelopus small-molecule chemical defenses has been primarily concerned with identifying and characterizing various forms of these toxins while largely overlooking their ecological roles and evolutionary implications. In addition to describing the extent of knowledge about Atelopus toxin structures, pharmacology, and biological sources, we review the detection, identification, and quantification methods used in studies of Atelopus toxins to date and conclude that many known toxin profiles are unlikely to be comprehensive because of methodological and sampling limitations. Patterns in existing data suggest that both environmental (toxin availability) and genetic (capacity to synthesize or sequester toxins) factors influence toxin profiles. From an ecological and evolutionary perspective, we summarize the possible selective pressures acting on Atelopus toxicity and toxin profiles, including predation, intraspecies communication, disease, and reproductive status. Ultimately, we intend to provide a basis for future ecological, evolutionary, and biochemical research on Atelopus.

Comparative transcriptomes of three different skin sites for the Asiatic toad (Bufo gargarizans)

Toads release toxic dry secretions from glands in their skin. Toxin possesses a wide range of biological effects, but little is known about its specific gene expression pattern and regulatory mechanisms. The Asiatic toad (Bufo gargarizans) is widely used to produce toxin. Here, we explored the gene expression of 30 tissue samples from three different skin sites (parotoid gland, dorsal skin, and abdomen skin) of B. gargarizans. After de novo assembly, 783,130 unigenes with an average length of 489 bp (N50 = 556 bp) were obtained. A total of 9,248 significant differentially expressed genes (DEGs) were detected. There were 8,819 DEGs between the parotoid gland and abdomen skin and 1,299 DEGs between the dorsal skin and abdomen skin, while only 1,283 DEGs were obtained between the parotoid gland and dorsal skin. Through enrichment analysis, it was found that the detected differential gene expressions corresponded to the different functions of different skin sites. Our key findings were the genetic expression of toxin secretion, the protection function of skin, and the related genes such as HSD3B, Cyp2c, and CAT, LGALS9. In conclusion, we provide useful transcript resources to study the gene expression and gene function of B. gargarizans and other amphibians. The detected DEGs between different sites of the skin provided better insights into the genetic mechanisms of toxin secretion and the protection function of skin for amphibians.

From Gondwana to the Yellow Sea, evolutionary diversifications of true toads Bufo sp. in the Eastern Palearctic and a revisit of species boundaries for Asian lineages

Taxa with vast distribution ranges often display unresolved phylogeographic structures and unclear taxonomic boundaries resulting in hidden diversity. This hypothesis-driven study reveals the evolutionary history of Bufonidae, covering the phylogeographic patterns found in Holarctic bufonids from the West Gondwana to the phylogenetic taxonomy of Asiatic true toads in the Eastern Palearctic. We used an integrative approach relying on fossilized birth-death calibrations, population dynamics, gene-flow, species distribution, and species delimitation modeling to resolve the biogeography of the clade and highlight cryptic lineages. We verified the near-simultaneous Miocene radiations within Western and Eastern Palearctic Bufo, c. 14.49-10.00 Mya, temporally matching with the maximum dust outflows in Central Asian deserts. Contrary to earlier studies, we demonstrated that the combined impacts of long dispersal and ice-age refugia equally contributed to the current genetic structure of Bufo in East Asia. Our findings reveal a climate-driven adaptation in septentrional Eastern Asian Bufo, explaining its range shifts toward northern latitudes. We resolve species boundaries within the Eastern Palearctic Bufo, and redefine the taxonomic and conservation units of the northeastern species: B. sachalinensis and its subspecies.

Screening of Bufadienolides from Toad Venom Identifies Gammabufotalin as a Potential Anti-inflammatory Agent

Toad venom (Chansu) is used in the treatment of infectious and inflammatory diseases in China and East/Southeast Asian countries. However, the anti-inflammatory components of toad venom have not yet been systematically evaluated and clearly defined. To investigate the anti-inflammatory effects of toad venom and identify new anti-inflammatory ingredients, we used zebrafish, an alternative drug screening model, to evaluate the anti-inflammatory effects of 14 bufadienolides previously isolated from toad venom. Most of the bufadienolides were found to exert significant anti-inflammatory effects on lipopolysaccharide-, CuSO₄-, or tail transection-induced zebrafish inflammatory models. Moreover, gammabufotalin ( 6: ) inhibits lipopolysaccharide-induced inflammation by suppressing the myeloid differentiation primary response 88/nuclear factor-kappa B and STAT3 signal pathways. This study confirms the potential of zebrafish in drug screening, clarifies the anti-inflammatory effects of bufadienolides from toad venom, and indicates that gammabufotalin may be developed as a novel therapeutic agent for inflammatory diseases in the future.

HuaChanSu suppresses tumor growth and interferes with glucose metabolism in hepatocellular carcinoma cells by restraining Hexokinase-2

Hepatocellular carcinoma (HCC) has become the sixth highly diagnosed cancer and the fourth main reason of cancer deaths worldwide. HuaChanSu, an extract from dried toad skin, exhibits good anticancer effects and has been widely used in the treatment of liver cancer. The reprogramming of glucose metabolism is one remarkable feature of hepatocellular carcinoma, and the effects of HuaChanSu on the abnormal glucose metabolism of cancer cells have not been elucidated. In our study, we investigate the effects of HuaChanSu on glucose metabolism of hepatocellular carcinoma cells and tumor growth in vivo. The results show that HuaChanSu inhibits the tumor growth of hepatoma H22-bearing mice and prolongs the survival time of tumor-bearing mice, additionally, HuaChanSu has no obvious adverse effects in these mice. In vitro, HuaChanSu restrains the proliferation, induces apoptosis and cell cycle arrest of human hepatoma cells. HuaChanSu also promotes ROS production and causes mitochondrial damage. Furthermore, HuaChanSu inhibits glucose uptake and lactate release in human hepatoma cells. Mechanistically, we find that HuaChanSu downregulates Hexokinase-2 (HK2) expression, and using RNA interference, we confirm that HuaChanSu suppresses the growth of HepG2 cells by interfering with glucose metabolism through downregulation of Hexokinase-2. However, knockdown of Hexokinase-2 has no obvious effect on the proliferation of SK-HEP-1 cells, although glucose uptake and lactate release are reduced in siHK2-transfected SK-HEP-1 cells, subsequently, we illustrate that two human hepatoma cell lines exhibit glucose metabolism heterogeneity, which causes the different cell proliferation responses to the inhibition of Hexokinase-2. Taken together, our study indicates that HuaChanSu could inhibit tumor growth and interfere with glucose metabolism via suppression of Hexokinase-2, and these findings provide a new insight into the anti-hepatoma mechanisms of HuaChanSu and lay a theoretical foundation for the further clinical application of HuaChanSu.

Material Basis and Mechanism of Chansu Injection for COVID-19 Treatment Based on Network Pharmacology and Molecular Docking Technology

Purpose

The clinical efficacy of Chansu injection for COVID-19 treatment has been confirmed. Its mechanism of action remains unclear. We used network pharmacology and molecular docking technology to explore the potential material basis and mechanism of action of Chansu injection for COVID-19.

Methods

The main components of Chansu injection were determined using HPLC. The PharmMapper, SwissTargetPrediction, SEA, and TCMID databases were used to screen for the active ingredients and therapeutic targets of Chansu injection, while the OMIM and GeneCards Suite databases were used to search for COVID-19-related targets. The STRING database was used for protein-protein interaction (PPI) network construction and topological analysis, while DAVID was used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the core targets. The main active compounds of Chansu injection were docked with 3CL protease, ACE2, RdRp, and spike protein.

Results

The three Chansu injection compounds were identified using HPLC. A total of 236 drug-related targets and 16,611 disease-related targets were identified, and 77 common targets were determined through mapping. The PPI mapping results revealed that 16 core targets were obtained through topological analysis and screening. Furthermore, GO and KEGG pathway enrichment analyses revealed that the PI3K and JAK-STAT signaling pathways are the major pathways. The molecular docking results suggest that the three Chansu injection components have high binding energies to the S protein.

Conclusions

The potential mechanism of Chansu injection for COVID-19 involves multiple targets and pathways, thereby providing a scientific basis for its clinical application and further research.

A rGO-DNAzyme assisted fluorescence method for sensitive RNase A activity assay and natural compound screening

As a key regulator of human physiology and metabolic processes, ribonuclease (RNase) A can be used as an important biomarker for predicting human disease occurrence. Hence, establishing sensitive methods for tracking RNase A activity in vitro and in living cells is of great importance. Herein, we present a convenient fluorescence method assisted by reduced graphene oxide (rGO) and DNAzyme mediated fluorescence signal release for RNase A assay. The fluorescence change of the new method showed a positive linear relation with RNase A concentration in the range from 0.5 pg μL^-1 to 1 ng μL^-1 with a detection limit of 0.089 pg μL^-1. By using this method to screen the effector of RNase A from natural compounds, the natural compound of B6 was found to stimulate RNase A activity in vitro and in vivo, the result of which was supported by the real-time imaging of RNase A in living cells. In summary, this fluorescence method with high sensitivity and specificity provides an alternative for RNase A activity assay and effector screening.

Medicinal Animals and Plants as Alternative and Complementary Medicine in Southern Regions of Khyber Pakhtunkhwa, Pakistan

Background: Local communities use animals and plants as common traditional therapies for various diseases. The study aimed to document animals and animal-plant mixture recipes that are used as alternative and complementary medicine in southern regions of Khyber Pakhtunkhwa, Pakistan.

Methods: The data were collected (2017–2018) in three remote areas (Dera Ismail Khan, Bannu, and Lakki Marwat) through questionnaires and face-to-face interviews with local inhabitants. Data on ethnomedicinal uses and cultural values of animal products or parts and their mixture with plants were analyzed using various indices such as frequency of citation (FC), informant consensus (FIC), and fidelity level (FL) to find the highly preferred species in the area.

Results: A total of 185 informants (117 females and 68 males) were interviewed. The study documented 32 animal species, vertebrates (n = 24) and invertebrates (n = 8), for curing 37 types of diseases. Mammals (n = 13) were among the most commonly utilized species followed by birds (n = 8), arthropods (n = 7), reptiles (n = 2), and fishes and annelids (n = 1 each). Among the reported animals, Herpestes edwardsi (mongoose), Macaca mulatta (monkey), Labeo rohita (rohu), Oryctolagus cuniculus (rabbit), and Streptopelia decaocto (dove) were the newly reported species used as alternative medicine. The meat of Capra hircus (goat), monkey, and rabbit was used to treat chronic diseases such as hepatitis C, cancer, epilepsy, and asthma. A total of 17 plants belonging to 15 botanical families were used in combination with animal parts/products. The commonly used families were Piperaceae (31%) followed by Apiaceae (27%). The notable plant species in combination with animal products were Curcuma longa, Piper nigrum, Coriandrum sativum, Brassica rapa, and Phoenix dactylifera. Seeds were the highest used part in animal-plant mixture recipes. Gallus gallus (chicken) and Columba livia (pigeon) secured the highest (FC = 28) and (FL = 80%), respectively. FIC results had shown the highest degree of consensus for general body weakness (FIC = 0.88) and pyrexia (FIC = 0.86).

Conclusion: Our findings suggest that local communities in the southern regions of Khyber Pakhtunkhwa have substantial knowledge about the formulation of ethnomedicines from both flora and fauna that need urgent documentation to avoid eroding and for conservational purposes. The newly reported phytozootherapeutic recipes and animal species can potentially be a source of pharmacologically active constituents and should be checked experimentally for further confirmation.

Bufadienolides from the Eggs of the Toad Bufo bufo gargarizans and Their Antimelanoma Activities

Toads produce potent toxins, named bufadienolides, to defend against their predators. Pharmacological research has revealed that bufadienolides are potential anticancer drugs. In this research, we reported nine bufadienolides from the eggs of the toad Bufo bufo gargarizans, including two new compounds (1 and 3). The chemical structures of 1 and 3, as well as of one previously reported semisynthesized compound (2), were elucidated on the basis of extensive spectroscopic data interpretation, chemical methods, and X-ray diffraction analysis. Compound 1 is an unusual 19-norbufadienolide with rearranged A/B rings. A biological test revealed that compounds 2 and 4-8 showed potent cytotoxic activities toward human melanoma cell line SK-MEL-1 with IC₅₀ values less than 1.0 μM. A preliminary mechanism investigation revealed that the most potent compound, 8, could induce apoptosis via PARP cleavage, while 5 and 6 significantly suppressed angiogenesis in zebrafish. Furthermore, an in vivo biological study showed that 5, 6, and 8 inhibit SK-MEL-1 cell growth significantly.

Bufothionine induces autophagy in H22 hepatoma-bearing mice by inhibiting JAK2/STAT3 pathway, a possible anti-cancer mechanism of cinobufacini

ETHNOPHARMACOLOGICAL RELEVANCE

Cinobufacini is extracted from the skins and parotid venom glands of the toad for treating symptoms like swelling and pain in ancient times. Nowadays, cinobifucini injection has also achieved satisfactory therapeutic effects on hepatocellular carcinoma (HCC) in China.

AIM OF THE STUDY

Our previous work found that bufothionine, an alkaloid abundant in cinobufacini injection, induced mitochondria-mediated apoptosis. In this work, the underlying effects of bufothionine on autophagy in HCC and its possible dependent pathway were investigated.

METHODS

CCK-8 and Hoechst staining assays were performed to verify effects of drugs on proliferation and apoptosis of SMMC7721 cell. H₂₂-tumor-bearing mice model was established by inoculating ascites fluid. HE staining was used to observe pathological changes in liver and tumor tissues. ELISA and Western blot experiments were conducted to investigate IL-6/JAK2/STAT3 signaling pathway. The effects of drugs on expressions of autophagic relative proteins were investigated by Western blot in vitro and in vivo.

RESULTS

In vitro, CCK-8 and Hoechst staining assays showed that bufothionine inhibited SMMC7721 cell proliferation and promoted apoptosis at 100 μM. In vivo, bufothionine relieved symptoms of H₂₂-tumor-bearing mice and exerted anti-inflammation activity. ELISA and Western blot demonstrated that bufothionine significantly reduced serum IL-6 concentration, suppressed p-Stat3tyr705, p-Stat3ser727 and Jak2 expressions in tumor tissues and upregulated Atg5, Atg7 and LC3Ⅱ expressions in SMMC7721 cell and H₂₂ tumor.

CONCLUSION

This is the first report showing that bufothionine might induce autophagy in HCC by inhibiting JAK2/STAT3 pathway, presenting a possible anti-cancer mechanism of bufothionine in cinobufacini injection.

Toad venom: A comprehensive review of chemical constituents, anticancer activities, and mechanisms

Toad venom, a traditional natural medicine, has been used for hundreds of years in China for treating different diseases. Many studies have been performed to elucidate the cardiotonic and analgesic activities of toad venom. Until the last decade, an increasing number of studies have documented that toad venom is a source of lead compound(s) for the development of potential cancer treatment drugs. Research has shown that toad venom contains 96 types of bufadienolide monomers and 23 types of indole alkaloids, such as bufalin, cinobufagin, arenobufagin, and resibufogenin, which exhibit a wide range of anticancer activities in vitro and, in particular, in vivo for a range of cancers. The main antitumor mechanisms are likely to be apoptosis or/and autophagy induction, cell cycle arrest, cell metastasis suppression, reversal of drug resistance, or growth inhibition of cancer cells. This review summarizes the chemical constituents of toad venom, analyzing their anticancer activities and molecular mechanisms for cancer treatments. We also outline the importance of further studies regarding the material basis and anticancer mechanisms of toad venom.

Tumor-Targeted Delivery of Bufalin-Loaded Modified Albumin-Polymer Hybrid for Enhanced Antitumor Therapy and Attenuated Hemolysis Toxicity and Cardiotoxicity

A novel albumin polymer hybrid with a core-shell structure was designed to target delivery of bufalin, which is an antineoplastic monomer with serious cardiotoxicity. The sheath layer was composed of ursodeoxycholic acid (UA)-modified bovine serum albumin (UA-BSA), while the stable core consisted of poly n-butyl cyanoacrylate (PBCA) nanoparticles. The UA-BSA was synthetized, and the substitution degree was characterized. The physical properties of bufalin-loaded UA-modified protein-PBCA nanocomplexes (BF-uPPNCs), such as morphology, particle size, and encapsulation efficiency, were evaluated. FTIR and DSC revealed the bufalin to be in an amorphous state. Furthermore, the in vitro release study indicated a sustained release profile of BF-uPPNCs. The MTT and cellular uptake study demonstrated that BF-uPPNCs significantly improved the inhibitory effect of the bufalin accompanied with an enhanced cell uptake capacity on HepG2 cells. In addition, in vivo research demonstrated that BF-uPPNCs had a better antitumor effect coupled with improved therapeutic effect, and reduced hemolysis, vascular irritation, and cardiotoxicity. This work therefore presented a novel albumin polymer hybrid with favorable stability, efficient tumor-targeted delivery potential, and side effect reduction ability, which can be a potential vehicle for an anticancer drug.

The Toxicity and Attenuation Methods of Toxic Chinese Materia Medica for its Reasonable Application: A Review

Over a millennia, traditional Chinese medicine (TCM) has been used to treat various diseases in China. In recent years, more and more Chinese materia medica (CMM) have been studied in scientific research projects, applied in clinical practice, and their extracts have even appeared in some health products. However, the toxicity of some CMM is often overlooked, including hepatotoxicity, nephrotoxicity, neurotoxicity, cardiotoxicity, etc. In this review, the toxic components and their toxicological mechanisms of some toxic CMM were listed according to the chemical structure classification of toxic components. Afterwards, the traditional methods (processing and compatibility) and modern methods (structural modification, biotransformation, etc.) of attenuation of CMM were discussed. Since ancient times, it has been said that "fight fire with fire, fight poison with poison," and toxic CMM are of great significance in the treatment of difficult and severe diseases. The rational application of toxic CMM and their components in clinical practice was also exemplified in this review. While the pharmacological effects of TCMs have been emphasized, the scientific attenuation and rational application of toxic components should be concerned. We hope this review can provide a reference for future related research.

Acetyl-bufalin shows potent efficacy against non-small-cell lung cancer by targeting the CDK9/STAT3 signalling pathway

BACKGROUND

Cyclin-dependent kinase 9 (CDK9) is a promising prognostic marker and therapeutic target in cancers. Bufalin is an effective anti-tumour agent; however, the clinical application of bufalin is limited due to its high toxicity. Acetyl-bufalin, the bufalin prodrug, was designed and synthesised with higher efficiency and lower toxicity.

METHODS

Three non-small-cell lung cancer (NSCLC) cell lines, a xenograft model and a patient-derived xenograft (PDX) model were used to examine the effects of acetyl-bufalin. CDK9/STAT3 involvement was investigated by knockdown with siRNA, proteome microarray assay, western blot analysis and co-immunoprecipitation experiments. Acute toxicity test and pharmacokinetics (PK) study were conducted to assess the safety and PK. The human NSCLC tissues were analysed to verify high CDK9 expression.

RESULTS

We showed that CDK9 induced NSCLC cell proliferation and that this effect was associated with STAT3 activation, specifically an increase in STAT3 phosphorylation and transcription factor activity. Acetyl-bufalin is an effective and safety inhibitor of the CDK9/STAT3 pathway, leading to the impediment of various oncogenic processes in NSCLC. Molecular docking and high-throughput proteomics platform analysis uncovered acetyl-bufalin directly binds to CDK9. Consequently, acetyl-bufalin impaired the complex formation of CDK9 and STAT3, decreased the expressions of P-STAT3, and transcribed target genes such as cyclin B1, CDC2, MCL-1, Survivin, VEGF, BCL2, and it upregulated the expression levels of BAX and caspase-3 activity. Acetyl-bufalin inhibited tumour growth in NSCLC xenograft and PDX models.

CONCLUSIONS

Acetyl-bufalin is a novel blocker of the CDK9/STAT3 pathway thus may have potential in therapy of NSCLC and other cancers.

The Parotoid Gland Secretion from Peruvian Toad Rhinella horribilis (Wiegmann, 1833): Chemical Composition and Effect on the Proliferation and Migration of Lung Cancer Cells

Since Rhinella sp. toads produce bioactive substances, some species have been used in traditional medicine and magical practices by ancient cultures in Peru. During several decades, the Rhinella horribilis toad was confused with the invasive toad Rhinella marina, a species documented with extensive toxinological studies. In contrast, the chemical composition and biological effects of the parotoid gland secretions (PGS) remain still unknown for R. horribilis. In this work, we determine for the first time 55 compounds from the PGS of R. horribilis, which were identified using HPLC-MS/MS. The crude extract inhibited the proliferation of A549 cancer cells with IC₅₀ values of 0.031 ± 0.007 and 0.015 ± 0.001 µg/mL at 24 and 48 h of exposure, respectively. Moreover, it inhibited the clonogenic capacity, increased ROS levels, and prevented the etoposide-induced apoptosis, suggesting that the effect of R. horribilis poison secretion was by cell cycle blocking before of G2/M-phase checkpoint. Fraction B was the most active and strongly inhibited cancer cell migration. Our results indicate that the PGS of R. horribilis are composed of alkaloids, bufadienolides, and argininyl diacids derivatives, inhibiting the proliferation and migration of A549 cells.

Identification of Antitumor Constituents in Toad Venom by Spectrum-Effect Relationship Analysis and Investigation on Its Pharmacologic Mechanism

(1) Background: Toad venom (Bufonis Venenum, known as ‘Chansu’ in Chinese), the secretion of the ear-side gland and skin gland of Bufo gargarizans cantor or Duttaphrynus melanostictus Schneider, has been utilized to treat several diseases in China for thousands of years. However, due to the chemical variability of the components, systematic chemical composition and the key pharmacophores in toad venom have not yet fully understood. Besides, it contains a variety of effective compounds with different physiological activity and chemotypes, mainly including alkaloids, bufogenins, bufotoxins, and so on. The recent pharmacological researches have demonstrated that several bufogenins have remarkable pharmacological effects, such as anti-inflammatory, analgesic effects, and anti-tumor effects. Aim of the study: To identify the bioactive compounds and pharmacophores originating from toad venom based on analyzing spectrum-effect relationship by chemometrics and to explore the anti-cancer mechanism primarily. (2) Materials and methods: Fingerprint of the 21 batches of samples was established using HPLC (High Performance Liquid Chromatography). The anti-tumor activity of extracts were determined by in-vitro assays. Chemometric analysis was used to establish the spectrum-effect model and screen for active ingredients. Pharmacodynamic tests for the screened active compound monomers were conducted with in-vitro assays. Further anti-tumor mechanisms were investigated using western blot and flow cytometry. (3) Results: The established spectrum-effect model has satisfactory fitting effect and predicting accuracy. The inhibitory effect of major screened compounds on lung carcinoma cells A549 were validated in vitro, demonstrating that arenobufagin, telocinobufogenin, and cinobufotalin had significant anti-tumor effects. Through further investigation of the mechanism by western blotting and flow cytometry, we elucidated that arenobufagin induces apoptosis in A549 cells with the enhanced expression of cleaved PARP (poly (ADP-ribose) polymerase). These results may provide valuable information for further structural modification of bufadienolides to treat lung cancer and a method for discovery of anti-tumor active compounds. Conclusions: Our research offers a more scientific method for screening the principal ingredients dominating the pharmacodynamic function. These screened compounds (arenobufagin, etc.) were proven to induce apoptosis by overactivation of the PARP-pathway, which may be utilized to make BRCA (breast cancer susceptibility gene) mutant cancer cells more vulnerable to DNA damaging agents and kill them.

Molecular mechanisms of bufadienolides and their novel strategies for cancer treatment

Bufadienolides are cardioactive C24 steroids with an α-pyrone ring at position C17. In the last ten years, accumulating studies have revealed the anticancer activities of bufadienolides and their underlying mechanisms, such as induction of autophagy and apoptosis, cell cycle disruption, inhibition of angiogenesis, epithelial-mesenchymal transition (EMT) and stemness, and multidrug resistance reversal. As Na⁺/K⁺-ATPase inhibitors, bufadienolides have inevitable cardiotoxicity. Short half-lives, poor stability, low plasma concentration and oral bioavailability in vivo are obstacles for their applications as drugs. To improve the drug potency of bufadienolides and reduce their side effects, prodrug strategies and drug delivery systems such as liposomes and nanoparticles have been applied. Therefore, systematic and recapitulated information about the antitumor activity of bufadienolides, with special emphasis on the molecular or cellular mechanisms, prodrug strategies and drug delivery systems, is of high interest. Here, we systematically review the anticancer effects of bufadienolides and the molecular or cellular mechanisms of action. Research advancements regarding bufadienolide prodrugs and their tumor-targeting delivery strategies are critically summarized. This work highlights recent scientific advances regarding bufadienolides as effective anticancer agents from 2011 to 2019, which will help researchers to understand the molecular pathways involving bufadienolides, resulting in a selective and safe new lead compound or therapeutic strategy with improved therapeutic applications of bufadienolides for cancer therapy.

Individual variation in cardiotoxicity of parotoid secretion of the common toad, Bufo bufo, depends on body size - first results

Anurans secrete a wide diversity of toxins from skin glands to defend themselves against predators and pathogens. Bufonids produce potent poison in parotoid macroglands located in the postorbital region. Parotoid secretion is a rich source of bioactive compounds with cardiotoxic, cytotoxic and hemolytic activity. Poison content and toxicity may vary between species, populations, and among conspecifics inhabiting the same area. In the present paper, we pre-analyzed the individual variation in cardiotoxicity of parotoid extract of common toads (Bufo bufo Linnaeus, 1758) and impact of body mass (BM), snout to vent length (SVL), and body condition (BC) of toad on the poison toxicity. We hypothesized that large toads produce poison with higher cardiotoxicity than smaller ones. Parotoid extract was fractionated by reverse phase chromatography, and then in vitro physiological bioassays were carried out on the semi-isolated hearts of the mealworm beetle (Tenebrio molitor Linnaeus, 1758) to determine cardiotoxicity of the whole poison and separated fractions. Generalized linear mixed models were used to determine effects of BM, SVL, and BC on the poison toxicity. We recorded significant changes in the insect heart contractility after treatment with the whole poison and separated fractions. We found an individual variation in cardiotoxicity of the parotoid extract which was explained by the body size of toad. Poison of smaller toads displayed a negative, whereas poison of larger toads positive, chronotropic effect on the heart contractility. Thus, we conclude that the effectiveness of parotoid secretion in repelling predators may vary depending on the toad individual size.

Safety reassessment of cinobufotalin injection: new findings into cardiotoxicity

Cinobufotalin injection, a traditional Chinese medicine preparation, successfully used for several years, might induce cardiotoxicity. The aim of the study was to evaluate the cardiotoxicity of cinobufotalin injection and the cardiotoxicity-preventive effect of sodium phenytoin in vivo. According to the 4 × 4 Latin square design, four Beagle dogs were allocated into four dose levels of 0, 0.3, 1, and 3 g/kg in treatment phases I-IV (cinobufotalin injection) and 3 g/kg in treatment phase V (cardiotoxicity antidote). The following parameters and endpoints were assessed: clinical observations, body weight, indicators of myocardial injury, and electrocardiogram (ECG) parameters. The cinobufotalin injection-related changes were observed in clinical observations (rapid breathing pattern), indicators of myocardial injury (increased cardiac troponin I, creatine kinase isoenzymes, and aspartate aminotransferase), and ECG graphics (arrhythmia) at 3 g/kg concentration in treatment phases I-IV. The cardiotoxicity of cinobufotalin injection was attenuated by sodium phenytoin in treatment phase V. The results confirmed the cardiotoxicity of cinobufotalin injection, and they might bring information about the appropriate monitoring time points and cardiotoxicity parameters in clinical practices and shed light on the treatment of cardiovascular adverse reactions.

Chanling Gao Attenuates Bone Cancer Pain in Rats by the IKKβ/NF-κB Signaling Pathway

Cancer pain is one of the most common and serious symptoms of cancer patients. At present, the agents used for the prevention or treatment of cancer pain do not act with optimal safety and efficacy. The nuclear factor kappa B (NF-κB) signaling pathway and its downstream inflammatory factors interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) play an important regulatory role in the developmental process of cancer pain. IKKβ is a key molecule of the IκB (IKK) kinase that propagates cellular responses to inflammation. Previous studies have shown that phosphorylation and degradation of the IκBα protein promotes the activation of NF-κB and the expression of TNF-α, IL-1β, and IL-6, participating in the formation and development of cancer pain. Chanling Gao (CLG) is a compound preparation of traditional Chinese medicine. It contains specific functions, namely nourishing Yin, activating blood circulation and relieving pain and dysfunction syndrome. It is used in the treatment of a variety of pain disorders including cancer-induced bone pain (CIBP), which has a certain relief effect. However, its mechanism of action still remains unclear. In the present study, a rat model of tibia CIBP was successfully established using the Walker 256 breast cancer cell line. The IKKβ/NF-κB signaling pathway and its related factors TNF-α, IL-1β, and IL-6 were used as the entry points to explore the effect of CLG on CIBP and their possible mechanisms of action. The results indicated that CLG improved the body mass of the CIBP rat model and increased the pain threshold in rats. CLG significantly inhibited the degradation of IκBα and the levels of p-IκBα, p-IKKβ, and p-p65 NF-κB proteins in the spinal cord of CIBP rats, inhibiting the contents of TNF-α, IL-1β, and IL-6. Therefore, we conclude that the analgesic effect of CLG in this rat model of CIBP may be related to the inhibition of the IKKβ/NF-κB signaling pathway and the reduction of synthesis and release of TNF-α, IL-1β, and IL-6.

Interpreting the Pharmacological Mechanisms of Huachansu Capsules on Hepatocellular Carcinoma Through Combining Network Pharmacology and Experimental Evaluation

Hepatocellular carcinoma (HCC) is one of the most fatal cancers across the world. Chinese medicine has been used as adjunctive or complementary therapy for the management of HCC. Huachansu belongs to a class of toxic steroids isolated from toad venom that has important anti-cancer property. This study was aimed to identify the bioactive constituents and molecular targets of Huachansu capsules (HCSCs) for treating HCC using network pharmacology analysis and experimental assays. The major bioactive components of HCSCs were determined using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A series of network pharmacology methods including target prediction, pathway identification, and network establishment were applied to identify the modes of action of HCSCs against HCC. Furthermore, a series of experiments, including MTT, clonogenic assay, 3-D transwell, wound healing assay, as well as flow cytometry, were conducted to verify the inhibitory ability of HCSCs on HCC in vitro. The results showed that 11 chemical components were identified from HCSCs. The network pharmacological analysis showed that there were 82 related anti-HCC targets and 14 potential pathways for these 11 components. Moreover, experimental assays confirmed the inhibitory effects of HCSCs against HCC in vitro. Taken together, our study revealed the synergistic effects of HCSCs on a systematic level, and suggested that HCSCs exhibited anti-HCC effects in a multi-component, multi-target, and multi-pathway manner.