Amitriptyline prevents CPT-11-induced early-onset diarrhea and colonic apoptosis without reducing overall gastrointestinal damage in a rat model of mucositis

Banxia Xiexin decoction combined with 5-ASA protects against CPT-11-induced intestinal dysfunction in rats via inhibiting TLR4/NF-κB signaling pathway

BACKGROUND

Banxia Xiexin decoction (BXD) can control irinotecan (CPT-11)-caused delayed diarrhea, but the corresponding mechanism remains undefined.

AIMS

This paper aimed to uncover the mechanism of BXD in regulating CPT-11-caused delayed diarrhea.

MATERIALS & METHODS

Sprague-Dawley (SD) rats were assigned into the control, model, BXD low-dose (BXD-L, 5 g/kg), BXD medium-dose (BXD-M, 10 g/kg), BXD high-dose (BXD-H, 15 g/kg), 5-aminosalicylic acid (5-ASA, 10 mL/kg), and BXD-M + 5-ASA groups. Rats were injected intraperitoneally with 150 mg/kg CPT-11 at Day 4 and Day 5 to induce delayed diarrhea, and later treated with various doses (low, medium, and high) of BXD and 5-ASA for 9 days, except for rats in control group. The body weight of rats was measured. The rat colon tissue injury, inflammatory cytokine levels, and the activation of toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) signaling pathway were detected.

RESULTS

BXD (5, 10, or 15 g/kg) or 5-ASA (10 mL/kg) alleviated body weight loss and colon tissue injury, decreased levels of inflammatory cytokines, and inactivated TLR4/NF-κB signaling pathway in CPT-11-induced model rats. BXD at 10 g/kg (the optimal concentration) could better treat CPT-11-induced intestinal dysfunction, as evidenced by the resulting approximately 50% reduction on injury score of model rats. Moreover, BXD-M (10 g/kg) synergistic with 5-ASA (10 mL/kg) further strengthened the inhibition on rat body weight loss, colon tissue injury, inflammatory cytokine levels, and TLR4/NF-κB signaling pathway.

CONCLUSION

To sum up, BXD has a protective effect against CPT-11-induced intestinal dysfunction by inhibiting inflammation through inactivation TLR4/NF-κB signaling pathway. In particular, the combined use of BXD and 5-ASA holds great promise for treating CPT-11-induced delayed diarrhea.

Experimental Chemotherapy-Induced Mucositis: A Scoping Review Guiding the Design of Suitable Preclinical Models

Mucositis is a common and most debilitating complication associated with the cytotoxicity of chemotherapy. The condition affects the entire alimentary canal from the mouth to the anus and has a significant clinical and economic impact. Although oral and intestinal mucositis can occur concurrently in the same individual, these conditions are often studied independently using organ-specific models that do not mimic human disease. Hence, the purpose of this scoping review was to provide a comprehensive yet systematic overview of the animal models that are utilised in the study of chemotherapy-induced mucositis. A search of PubMed/MEDLINE and Scopus databases was conducted to identify all relevant studies. Multiple phases of filtering were conducted, including deduplication, title/abstract screening, full-text screening, and data extraction. Studies were reported according to the updated Preferred Reporting Items for Systematic reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. An inter-rater reliability test was conducted using Cohen's Kappa score. After title, abstract, and full-text screening, 251 articles met the inclusion criteria. Seven articles investigated both chemotherapy-induced intestinal and oral mucositis, 198 articles investigated chemotherapy-induced intestinal mucositis, and 46 studies investigated chemotherapy-induced oral mucositis. Among a total of 205 articles on chemotherapy-induced intestinal mucositis, 103 utilised 5-fluorouracil, 34 irinotecan, 16 platinum-based drugs, 33 methotrexate, and 32 other chemotherapeutic agents. Thirteen articles reported the use of a combination of 5-fluorouracil, irinotecan, platinum-based drugs, or methotrexate to induce intestinal mucositis. Among a total of 53 articles on chemotherapy-induced oral mucositis, 50 utilised 5-fluorouracil, 2 irinotecan, 2 methotrexate, 1 topotecan and 1 with other chemotherapeutic drugs. Three articles used a combination of these drugs to induce oral mucositis. Various animal models such as mice, rats, hamsters, piglets, rabbits, and zebrafish were used. The chemotherapeutic agents were introduced at various dosages via three routes of administration. Animals were mainly mice and rats. Unlike intestinal mucositis, most oral mucositis models combined mechanical or chemical irritation with chemotherapy. In conclusion, this extensive assessment of the literature revealed that there was a large variation among studies that reproduce oral and intestinal mucositis in animals. To assist with the design of a suitable preclinical model of chemotherapy-induced alimentary tract mucositis, animal types, routes of administration, dosages, and types of drugs were reported in this study. Further research is required to define an optimal protocol that improves the translatability of findings to humans.

Structural insight and analysis of TLR4 interactions with IAXO-102, TAK-242 and SN-38: an in silico approach

Introduction

Toll-like receptor 4 (TLR4) has attracted interest due to its role in chemotherapy-induced gastrointestinal inflammation. This structural study aimed to provide in silico rational of the recognition and potential binding of TLR4 ligands IAXO-102, TAK-242, and SN-38 (the toxic metabolite of the chemotherapeutic irinotecan hydrochloride), which could contribute to rationale development of therapeutic anti-inflammation drugs targeting TLR4 in the gastrointestinal tract.

Methods

In silico docking was performed between the human TLR4-MD-2 complex and ligands (IAXO-102, TAK-242, SN-38) using Autodock Vina, setting the docking grids to cover either the upper or the lower bound of TLR4. The conformation having the lowest binding energy value (kcal/mol) was processed for post-hoc analysis of the best-fit model. Hydrogen bonding was calculated by using ChimeraX.

Results

Binding energies of IAXO-102, TAK-242 and SN-38 at the upper bound of TLR4-MD-2 ranged between - 3.8 and - 3.1, - 6.9 and - 6.3, and - 9.0 and - 7.0, respectively. Binding energies of IAXO-102, TAK-242 and SN-38 at the lower bound ranged between - 3.9 and - 3.5, - 6.5 and - 5.8, and - 8.2 and - 6.8, respectively. Hydrogen bonding at the upper bound of TLR4/MD-2 with IAXO-102, TAK-242 and SN-38 was to aspartic acid 70, cysteine 133 and serine 120, respectively. Hydrogen bonding at the lower bound of TLR4-MD-2 with IAXO-102, TAK-242 and SN-38 was to serine 528, glycine 480 and glutamine 510, respectively.

Conclusion

The in silico rational presented here supports further investigation of the binding activity of IAXO-102 and TAK-242 for their potential application in the prevention of gastrointestinal inflammation caused by SN-38.

Investigation of the Possible Protective Effect of N-Acetylcysteine (NAC) against Irinotecan (CPT-11)-Induced Toxicity in Rats

Irinotecan (CPT-11) is a chemotherapeutic agent involved in the treatment regimens for several malignancies such as colorectal cancer. N-acetylcysteine (NAC) is a strong antioxidant and anti-inflammatory agent used in the treatment of several diseases related to oxidative stress and inflammation. This study aimed at investigating whether NAC provides protection against hepatorenal and gastrointestinal tissue damage induced by CPT-11. Thirty-two Wistar albino rats were divided into four groups as control, NAC, CPT-11, and CPT-11+NAC. Following the experimental period, blood, and tissue samples (liver, kidney, stomach, and small intestine) were collected, and biochemical indicators, together with pro-inflammatory cytokines (TNF-α and IL-1β), matrix metalloproteinases (MMPs), malondialdehyde (MDA), glutathione peroxidase (GPx) and superoxide dismutase (SOD) levels were evaluated. Both the biochemical indicators and the pro-inflammatory cytokines, MMP, and MDA levels increased in animals treated with CPT-11, while SOD and GPx activities decreased. Histopathological evaluation revealed structural damage in all examined tissues. With NAC administration, significant improvements were observed, both biochemically and histologically. In conclusion, the results of the present study suggest that NAC treatment together with CPT-11 may have a beneficial effect on reducing CPT-11 toxicity in rats, by modulating inflammation and the oxidant-antioxidant balance. These results strongly promote further investigative studies.

Effects of a novel toll-like receptor 4 antagonist IAXO-102 in a murine model of chemotherapy-induced gastrointestinal toxicity

INTRODUCTION

Gastrointestinal mucositis (GIM) is a side effect of high-dose irinotecan (CPT-11), causing debilitating symptoms that are often poorly managed. The role of TLR4 in the development of GIM has been clearly demonstrated. We, therefore, aimed to investigate the potential of the TLR4 antagonist, IAXO-102, to attenuate gastrointestinal inflammation as well as supress tumour activity in a colorectal-tumour-bearing mouse model of GIM induced by CPT-11.

METHODS

24 C57BL/6 mice received a vehicle, daily i.p. IAXO-102 (3 mg/kg), i.p. CPT-11 (270 mg/kg) or a combination of CPT-11 and IAXO-102. GIM was assessed using validated toxicity markers. At 72 h, colon and tumour tissue were collected and examined for histopathological changes and RT-PCR for genes of interest; TLR4, MD-2, CD-14, MyD88, IL-6, IL-6R, CXCL2, CXCR1, and CXCR2.

RESULTS

IAXO-102 prevented diarrhoea in mice treated with CPT-11. Tumour volume in IAXO-102-treated mice was lower compared to vehicle at 48 h (P < 0.05). There were no differences observed in colon and tumour weights between the treatment groups. Mice who received the combination treatment had improved tissue injury score (P < 0.05) in the colon but did not show any improvements in cell proliferation or apoptotic rate. Expression of all genes was similar across all treatment groups in the tumour (P > 0.05). In the colon, there was a difference in transcript expression in vehicle vs. IAXO-102 (P < 0.05) and CPT-11 vs. combination (P < 0.01) in MD-2 and IL-6R, respectively.

CONCLUSION

IAXO-102 was able to attenuate symptomatic parameters of GIM induced by CPT-11 as well as reduce tissue injury in the colon. However, there was no effect on cell proliferation and apoptosis. As such, TLR4 activation plays a partial role in GIM development but further research is required to understand the specific inflammatory signals underpinning tissue-level changes.

Chemotherapy-Induced Intestinal Microbiota Dysbiosis Impairs Mucosal Homeostasis by Modulating Toll-like Receptor Signaling Pathways

Chemotherapy-induced intestinal mucositis, a painful debilitating condition affecting up to 40–100% of patients undergoing chemotherapy, can reduce the patients’ quality of life, add health care costs and even postpone cancer treatment. In recent years, the relationships between intestinal microbiota dysbiosis and mucositis have drawn much attention in mucositis research. Chemotherapy can shape intestinal microbiota, which, in turn, can aggravate the mucositis through toll-like receptor (TLR) signaling pathways, leading to an increased expression of inflammatory mediators and elevated epithelial cell apoptosis but decreased epithelial cell differentiation and mucosal regeneration. This review summarizes relevant studies related to the relationships of mucositis with chemotherapy regimens, microbiota, TLRs, inflammatory mediators, and intestinal homeostasis, aiming to explore how gut microbiota affects the pathogenesis of mucositis and provides potential new strategies for mucositis alleviation and treatment and development of new therapies.

NIR triggered PLGA coated Au-TiO2 core loaded CPT-11 nanoparticles for human papillary thyroid carcinoma therapy

MDR (multi-drug resistance) is one of the significant deterrents of effective chemotherapy for malignant growth. One of the powerful ways to deal with defeat of the MDR is to utilize inorganic nanoparticle-intervened tranquilize conveyance to build the medication aggregations in cancerous growth cells. In this work, we have developed the presentation that is accurately made of medication conveyance framework dependent on the TiO₂ nanoparticles stacked CPT-11 to defeat the thyroid malignancy cells. The synthesized nanoparticles are characterized by spectroscopy methods (UV–vis, XPS, SEM, TEM, and DLS). The TEM results suggested that the shape of PLGA-Au-TiO₂@CPT-11 of nanoparticles is ∼250 nm. After successful synthesis, we have evaluated the MTT of PLGA-Au-TiO₂@CPT-11 nanoparticles with and without NIR radiations. Further, the morphological changes were observed using various biochemical stainings, such as acridine orange and ethidium bromide (AO–EB) and nuclear staining through Hoechst-33258. Also, migration and cell invasion were examined. The results show that these PLGA-Au-TiO₂@CPT-11 and PLGA-Au-TiO₂@CPT-11 + NIR nanoparticles exhibited promising antimetastatic property and reduced the cell invasion activity in B-CPAP and FTC-133 thyroid cancer cell lines. Based on the above findings, these PLGA-Au-TiO₂@CPT-11 and PLGA-Au-TiO₂@CPT-11 + NIR nanoparticles can be used as a promising candidate for the malignant thyroid cells.

Irinotecan: 25 years of cancer treatment

Twenty-five years ago, the cytotoxic drug irinotecan (IRT) was first approved in Japan for the treatment of cancer. For more than two decades, the IRT prodrug has largely contributed to the treatment of solid tumors worldwide. Nowadays, this camptothecin derivative targeting topoisomerase 1 remains largely used in combination regimen, like FOLFIRI and FOLFIRINOX, to treat metastatic or advanced solid tumors, such as colon, gastric and pancreatic cancers and others. This review highlights recent discoveries in the field of IRT and its derivatives, including analogues of the active metabolite SN38 (such as FL118), the recently approved liposomal form Nal-IRI and SN38-based immuno-conjugates currently in development (such as sacituzumab govitecan). New information about the IRT mechanism of action are presented, including the discovery of a new protein target, the single-stranded DNA-binding protein FUBP1. Significant progress has been made also to better understand and manage the main limiting toxicities of IRT, chiefly neutropenia and diarrhea. The role of drug-induced inflammation and dysbiosis is underlined and strategies to limit the intestinal toxicity of IRT are discussed (use of β-glucuronidase inhibitors, plant extracts, probiotics). The detailed knowledge of the metabolism of IRT has enabled the identification of potential biomarkers to guide patient selection and to limit drug-induced toxicities, but no robust IRT-specific therapeutic biomarker has been approved yet. IRT is a versatile chemotherapeutic agent which combines well with a variety of anticancer drugs. It offers a large range of drug combinations with cytotoxic agents, targeted products and immuno-active biotherapeutics, to treat a variety of advanced solid carcinoma, sarcoma and cancers with progressive central nervous system diseases. A quarter of century after its first launch, IRT remains an essential anticancer drug, largely prescribed, useful to many patients and scientifically inspiring.