Hepatotoxic evaluation of toosendanin via biomarker quantification and pathway mapping of large-scale chemical proteomics

Analysis of Clinical Trials Using Anti-Tumor Traditional Chinese Medicine Monomers

The potential anti-cancer effect of traditional Chinese medicine (TCM) monomers has been widely studied due to their advantages of well-defined structure, clear therapeutic effects, and easy quality control during the manufacturing process. However, clinical trial information on these monomers is scarce, resulting in a lack of knowledge regarding the research progress, efficacy, and adverse reactions at the clinical stage. Therefore, this study systematically reviewed the clinical trials on the anti-cancer effect of TCM monomers registered in the Clinicaltrials.gov website before 2023.4.30, paying special attention to the trials on tumors, aiming to explore the research results and development prospects in this field. A total of 1982 trials were started using 69 of the 131 TCM monomers. The number of clinical trials performed each year showed an overall upward trend. However, only 26 monomers entered into 519 interventional anti-tumor trials, with vinblastine (194, 37.38%) and camptothecin (146, 28.13%) being the most used. A total of 45 tumors were studied in these 519 trials, with lymphoma (112, 21.58%) being the most frequently studied. Clinical trials are also unevenly distributed across locations and sponsors/collaborators. The location and the sponsor/collaborator with the highest number of performed trials were the United States (651,32.85%) and NIH (77). Therefore, China and its institutions still have large room for progress in promoting TCM monomers in anti-tumor clinical trials. In the next step, priority should be given to the improvement of the research and development ability of domestic enterprises, universities and other institutions, using modern scientific and technological means to solve the problems of poor water solubility and strong toxic and side effects of monomers, so as to promote the clinical research of TCM monomers.

Toosendanin induces hepatotoxicity via disrupting LXRα/Lipin1/SREBP1 mediated lipid metabolism

Toosendanin (TSN) is the main active compound derived from Melia toosendan Sieb et Zucc with various bioactivities. However, liver injury was observed in TSN limiting its clinical application. Lipid metabolism plays a crucial role in maintaining cellular homeostasis, and its disruption is also essential in TSN-induced hepatotoxicity. This study explored the hepatotoxicity caused by TSN in vitro and in vivo. The lipid droplets were significantly decreased, accompanied by a decrease in fatty acid transporter CD36 and crucial enzymes in the lipogenesis including ACC and FAS after the treatment of TSN. It was suggested that TSN caused lipid metabolism disorder in hepatocytes. TOFA, an allosteric inhibitor of ACC, could partially restore cell survival via blocking malonyl-CoA accumulation. Notably, TSN downregulated the LXRα/Lipin1/SREBP1 signaling pathway. LXRα activation improved cell survival and intracellular neutral lipid levels, while SREBP1 inhibition aggravated the cell damage and caused a further decline in lipid levels. Male Balb/c mice were treated with TSN (5, 10, 20 mg/kg/d) for 7 days. TSN exposure led to serum lipid levels aberrantly decreased. Moreover, the western blotting results showed that LXRα/Lipin1/SREBP1 inhibition contributed to TSN-induced liver injury. In conclusion, TSN caused lipid metabolism disorder in liver via inhibiting LXRα/Lipin1/SREBP1 signaling pathway.

Role of covalent modification by hepatic aldehydes in dictamnine-induced liver injury

Dictamnine is a representative furan-containing hepatotoxic compound. Administration of dictamnine caused acute liver injury in mice and the metabolic activation of furan to reactive epoxy intermediate was responsible for the hepatotoxicity. This study aimed to characterize the protein adduction by endogenous hepatic aldehydes and investigate its role in dictamnine-induced hepatotoxicity. In the liver sample of dictamnine-treated mice, the protein adduction by five aldehydes was characterized as lysine residue-aldehyde adducts using high-resolution UPLC-Q/Orbitrap MS after exhaustive proteolytic digestion. The levels of protein adduct were increased at 2-3 h after the treatment with dictamnine. The formation of protein adduction increased with increasing doses of dictamnine. Inhibition of the bioactivation by CYP3A inhibitor ketoconazole prevented the protein adduction. Treatment with 2,3-dihydro-dictamnine, an analog of dictamnine that was unable to form the epoxy intermediate, did not lead to an increase in protein adduction. Application of aldehyde dehydrogenase-2 activator ALDA-1 or nucleophilic trapping reagent N-acetyl-L-lysine significantly reduced the protein adduction and attenuated dictamnine-induced liver injury without affecting the bioactivation. In conclusion, the metabolic activation of the furan ring of dictamnine resulted in the protein adduction by multiple hepatic aldehydes and the protein modification played a crucial role in dictamnine-induced liver injury.

Therapeutic potential of toosendanin: Novel applications of an old ascaris repellent as a drug candidate

Toosendanin (TSN), extracted from Melia. toosendan Sieb.et Zucc. and Melia. azedarach L., has been developed into an ascaris repellent in China. However, with the improvement of public health protection, the incidence of ascariasis has been reduced considerably, resulting in limited medical application of TSN. Therefore, it is questionable whether this old ascaris repellent can develop into a drug candidate. Modern studies have shown that TSN has strong pharmacological activities, including anti-tumor, anti-botulinum, anti-viral and anti-parasitic potentials. It also can regulate fat formation and improve inflammation. These researches indicate that TSN has great potential to be developed into a corresponding medical product. In order to better development and application of TSN, the availability, pharmacodynamics, pharmacokinetics and toxicology of TSN are summarized systematically. In addition, this review discusses shortcomings in the current researches and provides useful suggestions about how TSN developed into a drug candidate. Therefore, this paper illustrates the possibility of developing TSN as a medical product, aimed to provide directions for the clinical application and further research of TSN.

Ferulic acid prevents Diosbulbin B-induced liver injury by inhibiting covalent modifications on proteins

Diosbulbin B (DIOB) has been reported to cause serious liver injury. However, in traditional medicine, DIOB-containing herbs are highly safe in combination with ferulic acid (FA)-containing herbs, suggesting potential neutralizing effect of FA on the toxicity of DIOB. DIOB can be metabolized to generate reactive metabolites (RMs), which can covalently bind to proteins and lead to hepatoxicity. In the present study, the quantitative method was firstly established for investigating the correlation between DIOB RM-protein adducts (DRPAs) and hepatotoxicity. Then, we estimated the detoxication effect of FA in combination with DIOB and revealed the underlying mechanism. Our data indicated that the content of DRPAs positively correlate with the severity of hepatotoxicity. Meanwhile, FA is able to reduce the metabolic rate of DIOB in vitro. Moreover, FA suppressed the production of DRPAs and decreased the serum alanine/aspartate aminotransferase (ALT/AST) levels elevated by DIOB in vivo. Thus, FA can ameliorate DIOB-induced liver injury through reducing the production of DRPAs.

Profiling protein targets of cellular toxicant exposure

Environmental agents of exposure can damage proteins, affecting protein function and cellular protein homeostasis. Specific residues are inherently chemically susceptible to damage from individual types of exposure. Amino acid content is not completely predictive of protein susceptibility, as secondary, tertiary, and quaternary structures of proteins strongly influence the reactivity of the proteome to individual exposures. Because we cannot readily predict which proteins will be affected by which chemical exposures, mass spectrometry-based proteomic strategies are necessary to determine the protein targets of environmental toxins and toxicants. This review describes the mechanisms by which environmental exposure to toxins and toxicants can damage proteins and affect their function, and emerging omic methodologies that can be used to identify the protein targets of a given agent. These methods include target identification strategies that have recently revolutionized the drug discovery field, such as activity-based protein profiling, protein footprinting, and protein stability profiling technologies. In particular, we highlight the necessity of multiple, complementary approaches to fully interrogate how protein integrity is challenged by individual exposures.

Flavonoids and saponins: What have we got or missed?

BACKGROUND

Flavonoids and saponins are important bioactive compounds that have attracted wide research interests. This review aims to summarise the state of the art of the pharmacology, toxicology and clinical efficacy of these compounds.

METHODS

Data were retrieved from PubMed, Cochrane Library, Web of Science, Proquest, CNKI, Chongqing VIP, Wanfang, NPASS and HIT 2.0 databases. Meta-analysis and systematic reviews were evaluated following the PRISMA guideline. Statistical analyses were conducted using SPSS23.0.

RESULTS

Rising research trends on flavonoids and saponins were observed since the 1990s and the 2000s, respectively. Studies on pharmacological targets and activities of flavonoids and saponins represent an important area of research advances over the past decade, and these important resources have been documented in open-access specialised databases and can be retrieved with ease. The rising research on flavonoids and saponins can be attributed, at least in part, to their links with some highly investigated fields of research, e.g., oxidative stress, inflammation and cancer; i.e., 6.88% and 3.03% of publications on oxidative stress cited by PubMed in 1990 - 2021 involved flavonoids and saponins, respectively, significantly higher than the percentage involving alkaloids (1.88%). The effects of flavonoids concern chronic venous insufficiency, cervical lesions, diabetes, rhinitis, dermatopathy, prostatitis, menopausal symptoms, angina pectoris, male pattern hair loss, lymphocytic leukaemia, gastrointestinal diseases and traumatic cerebral infarction, etc, while those of saponins may have impact on venous oedema in chronic deep vein incompetence, erectile dysfunction, acute impact injuries and systemic lupus erythematosus, etc. The volume of in vitro research appears way higher than in vivo and clinical studies, with only 10 meta-analyses and systematic reviews (involving 290 interventional and observational studies), and 36 clinical studies on flavonoids and saponins. Data are sorely needed on pharmacokinetics, in vitro pan-assay interferences, purity of tested compounds, interactions in complex herbal extracts, real impact of anti-oxidative strategies, and mid- and long-term toxicities. To fill these important gaps, further investigations are warranted. On the other hand, drug interactions may cause adverse effects but might also be useful for synergism, with the goals of enhancing effects or of detoxifying. Furthermore, the interactions between phytochemicals and the intestinal microbiota are worth investigating as the field may present a promising potential for novel drug development.

Toosendanin, a late-stage autophagy inhibitor, sensitizes triple-negative breast cancer to irinotecan chemotherapy

Background

Triple-negative breast cancer (TNBC) is a highly aggressive subtype of breast cancer that develops resistance to chemotherapy frequently. Autophagy has been reported as a pro-survival response to chemotherapeutic drugs in TNBC, and suppression of autophagy can be a strategy to overcome drug resistance.

Methods

The efficacy of toosendanin (TSN) in blocking autophagy flux was measured by western blot analysis of autophagy markers, and the fluorescent imaging of RFP-GFP-LC3 probe. The co-localization of autophagosomes and lysosomes was analyzed by fluorescent imaging. Then, lysosome function was determined by measuring the lysosomal pH value and the activity of lysosomal hydrolytic proteases. For in vitro study, human triple-negative breast cancer MDA-MB-231 and MDA-MB-436 cell lines were used for evaluating the anti-proliferative effect. For in vivo study, the RFP-GFP-LC3 MDA-MB-231 xenograft nude mice received intraperitoneal injection of irinotecan (10 mg/kg), TSN (0.5 mg/kg) or a combination, and the autophagy activity and cell apoptosis were determined in tumor tissue. The degree of pathological injury of tissue was evaluated by liver index.

Results

The natural autophagy inhibitor TSN, a triterpenoid extracted from Melia toosenda Sieb. et Zucc, potently inhibited late-stage autophagy in TNBC cells. This effect was achieved via elevating lysosome pH rather than blocking the fusion of autophagosomes and lysosomes. We further investigated the effects of TSN on the in vitro and in vivo TNBC models, in combination with chemotherapeutic drug irinotecan (or its active metabolite 7-ethyl-10-hydroxycamptothecin), a topoisomerase I inhibitor showing therapeutic potential for TNBC. The data showed that TSN blocked 7-ethyl-10-hydroxycamptothecin (SN-38)/irinotecan-induced protective autophagy, and significantly induced apoptosis in TNBC cells and tumor xenograft models when compared to SN-38/irinotecan alone group.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00605-8.

Evolving Roles of Natural Terpenoids From Traditional Chinese Medicine in the Treatment of Osteoporosis

Osteoporosis (OP) is a systemic metabolic skeletal disease which can lead to reduction in bone mass and increased risk of bone fracture due to the microstructural degradation. Traditional Chinese medicine (TCM) has been applied in the prevention and treatment of osteoporosis for a long time. Terpenoids, a class of natural products that are rich in TCM, have been widely studied for their therapeutic efficacy on bone resorption, osteogenesis, and concomitant inflammation. Terpenoids can be classified in four categories by structures, monoterpenoids, sesquiterpenoids, diterpenoids, and triterpenoids. In this review, we comprehensively summarize all the currently known TCM-derived terpenoids in the treatment of OP. In addition, we discuss the possible mechanistic-of-actions of all four category terpenoids in anti-OP and assess their therapeutic potential for OP treatment.

Toosendanin triggered hepatotoxicity in zebrafish via inflammation, autophagy, and apoptosis pathways

Toosendanin (TSN) is a crucial component from Toosendan Fructus with a promising anti-tumor capacity. It is also the primary suspect hepatotoxic component of Toosendan Fructus. However, the mechanisms underlying TSN-induced liver injury are still largely unknown. In present study, we evaluated the hepatotoxicity of TSN on zebrafish and explored the role of inflammation, autophagy, and apoptosis in TSN-induced hepatotoxicity. We found that TSN treatment decreased the area and fluorescence intensity of zebrafish liver in time- and dose-dependent manners at nonlethal concentrations. The ALT and AST activities were increased after TSN treatment. Severe cytoplasmic vacuolation and nuclear shrank were found in the liver of TSN-treated zebrafish. The expression profile of genes demonstrated that inflammation, autophagy and apoptosis pathways were involved in TSN-induced hepatotoxicity. Our study demonstrated for the first time that TSN treatment gave rise to liver injury in zebrafish, and inflammation, autophagy, apoptosis played a role in TSN-induced hepatotoxicity.