The male reproductive toxicity after 5-Fluorouracil exposure: DNA damage, oxidative stress, and mitochondrial dysfunction in vitro and in vivo

5-Fluorouracil (5-FU), a chemotherapeutic drug used to treat a variety of cancers, can enter the environment through different routes, causing serious public health and environmental concerns. It has been reported that 5-FU exposure adversely affects male reproductive function, and its effects on this system cannot be avoided. In this study, using western blotting and quantitative polymerase chain reaction studies, we found that 5-FU promoted testicular injury by inducing oxidative stress, which was accompanied by the inhibition of nuclear factor erythroid 2-related factor 2/antioxidant response element signaling. Accumulation of reactive oxygen species (ROS) aggravated 5-FU-mediated mitochondrial dysfunction and apoptosis in murine cell lines and testes, indicating oxidative stress and mitochondrial-dependent apoptotic signaling play crucial roles in the damage of spermatogenic cells caused. N-Acetyl-L-cysteine, an antioxidant that scavenges intracellular ROS, protected spermatogenic cells from 5-FU-induced oxidative damage and mitochondrial dysfunction, revealing the important role of ROS in testicular dysfunction caused by 5-FU. We found that 5-FU exposure induces testicular cell apoptosis through ROS-mediated mitochondria pathway in mice. In summary, our findings revealed the reproductive toxicological effect of 5-FU on mice and its mechanism, provided basic data reference for adverse ecological and human health outcomes associated with 5-FU contamination or poisoning.

Xianglian Pill combined with 5-fluorouracil enhances antitumor activity and reduces gastrointestinal toxicity in gastric cancer by regulating the p38 MAPK/NF-κB signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Perioperative or postoperative adjuvant chemotherapy based on 5-fluorouracil (5-FU) is a common first-line adjuvant therapy for gastric cancer (GC). However, drug resistance and the side effects of 5-FU have reduced its efficacy. Among these side effects, gastrointestinal (GI) toxicity is one of the most common. Xianglian Pill (XLP) is a Chinese patent medicine that is commonly used for the treatment of diarrhoea. It can reduce inflammation and has a protective effect on the intestinal mucosa. Recent studies have shown that many components of XLP can inhibite tumor cell growth. However, the therapeutic effect of XLP in combination with 5-FU on GC is unclear.

AIM OF THE STUDY

To investigate whether the combination of XLP and 5-FU can enhance anti-GC activity while reducing GI toxicity.

MATERIALS AND METHODS

XLP was administered orally during intraperitoneal injection of 5-FU in GC mice model. Mice were continuously monitored for diarrhea and xenograft tumor growth. After 2 weeks, the mice were sacrificed and serum was collected to determine interleukin-6 levels. Pathological changes, the expression of pro-inflammatory factors and p38 mitogen-activated protein kinase (MAPK) in GI tissue were determined by Western blot analysis. Pathological changes, apoptosis levels and p38 MAPK expression levels in xenograft tissues were also determined.

RESULTS

The results showed that XLP could alleviate GI mucosal injury caused by 5-FU, alleviated diarrhea, and inhibited the expression of nuclear factor (NF)-κB and myeloid differentiation primary response-88. Besides, XLP could promote the 5-FU-induced apoptosis of GC cells and enhance the inhibitory effect of 5-FU on tumor xenografts. Further study showed that XLP administration could regulate the expression of p38 MAPK.

CONCLUSIONS

XLP in combination with 5-FU could alleviate its GI side effects and enhance its inhibitory effect on xenograft tumor. Moreover, these effects were found to be related to the regulation of the p38 MAPK/NF-κB pathway.

[Developmental toxicity of Cry1Ab protein in the embryonic stem-cell model]

OBJECTIVE

To evaluate the developmental toxicity of Cry1Ab protein by studying its effects on cell proliferation and differentiation ability using a developmental toxicity assessment model based on embryonic stem-cell.

METHODS

Cry1Ab protein was tested in seven dose groups (31.25, 62.50, 125.00, 250.00, 320.00, 1 000.00, and 2 000.00 μg/L) on mouse embryonic stem cells D3 (ES-D3) and 3T3 mouse fibroblast cells, with 5-fluorouracil (5-FU) used as the positive control and phosphate buffer saline (PBS) as the solvent control. Cell viability was detected by CCK-8 assay to calculate the 50% inhibitory concentration (IC50) of the test substance for different cells. Additionally, Cry1Ab protein was tested in five dose groups (125.00, 250.00, 320.00, 1 000.00, and 2 000.00 μg/L) on ES-D3 cells, with PBS as the solvent control and 5-FU used for model validation. After cell treatment, cardiac differentiation was induced using the embryonic bodies (EBs) culture method. The growth of EBs was observed under a microscope, and their diameters on the third and fifth days were measured. The proportion of EBs differentiating into beating cardiomyocytes was recorded, and the 50% inhibition concentration of differentiation (ID50) was calculated. Based on a developmental toxicity discrimination function, the developmental toxicity of the test substances was classified. Furthermore, at the end of the culture period, mRNA expression levels of cardiac differentiation-related markers (Oct3/4, GATA-4, Nkx2.5, and β-MHC) were quantitatively detected using real-time quantitative polymerase chain reaction (qPCR) in the collected EBs samples.

RESULTS

The IC50 of 5-FU was determined as 46.37 μg/L in 3T3 cells and 32.67 μg/L in ES-D3 cells, while the ID50 in ES-D3 cells was 21.28 μg/L. According to the discrimination function results, 5-FU was classified as a strong embryotoxic substance. There were no statistically significant differences in cell viability between different concentrations of Cry1Ab protein treatment groups and the control group in both 3T3 cells and ES-D3 cells (P>0.05). Moreover, there were no statistically significant differences in the diameter of EBs on the third and fifth days, as well as their morphology, between the Cry1Ab protein treatment groups and the control group (P>0.05). The cardiac differentiation rate showed no statistically significant differences between different concentrations of Cry1Ab protein treatment groups and the control group (P>0.05). 5-FU significantly reduced the mRNA expression levels of β-MHC, Nkx2.5, and GATA-4 (P < 0.05), showing a dose-dependent trend (P < 0.05), while the mRNA expression levels of the pluripotency-associated marker Oct3/4 exhibited an increasing trend (P < 0.05). However, there were no statistically significant differences in the mRNA expression levels of mature cardiac marker β-MHC, early cardiac differentiation marker Nkx2.5 and GATA-4, and pluripotency-associated marker Oct3/4 between the Cry1Ab protein treatment groups and the control group (P>0.05).

CONCLUSION

No developmental toxicity of Cry1Ab protein at concentrations ranging from 31.25 to 2 000.00 μg/L was observed in this experimental model.

Protective effect of thymoquinone nanoemulsion in reducing the cardiotoxic effect of 5-fluorouracil in rats

5-Fluorouracil (5-FU), which is one of the most widely used chemotherapy drugs, has various side effects on the heart. Thymoquinone (TMQ), the main bioactive component of Nigella sativa, has antioxidant and protective effects against toxicity. In this study, we investigated the protective effect of thymoquinone against cardiotoxicity caused by 5-FU in vitro and in vivo models. H9C2 cells were exposed to 5-FU and TMQ, and cell viability was evaluated in their presence. Also, 25 male Wistar rats were divided into five control groups, 5-FU, 2.5, and 5 mg TMQ in nanoemulsion form (NTMQ) + 5-FU and 5 mg NTMQ. Cardiotoxicity was assessed through electrocardiography, cardiac enzymes, oxidative stress markers, and histopathology. 5-FU induced cytotoxicity in H9c2 cells, which improved dose-dependently with NTMQ cotreatment. 5-FU caused body weight loss, ECG changes (increased ST segment, prolonged QRS, and QTc), increased cardiac enzymes (aspartate aminotransferase [AST], creatine kinase-myocardial band [CK-MB], and lactate dehydrogenase [LDH]), oxidative stress (increased malondialdehyde, myeloperoxidase, nitric acid; decreased glutathione peroxidase enzyme activity), and histological damage such as necrosis, hyperemia, and tissue hyalinization in rats. NTMQ ameliorated these 5-FU-induced effects. Higher NTMQ dose showed greater protective effects. Thus, the results of our study indicate that NTMQ protects against 5-FU cardiotoxicity likely through antioxidant mechanisms. TMQ warrants further research as an adjuvant to alleviate 5-FU chemotherapy side effects.

Downregulating miRNA-199a-5p exacerbates fluorouracil-induced cardiotoxicity by activating the ATF6 signaling pathway

BACKGROUND

Fluorouracil (5-FU) might produce serious cardiac toxic reactions. miRNA-199a-5p is a miRNA primarily expressed in myocardial cells and has a protective effect on vascular endothelium. Under hypoxia stress, the expression level of miRNA-199a-5p was significantly downregulated and is closely related to cardiovascular events such as coronary heart disease, heart failure, and hypertension. We explored whether 5-FU activates the endoplasmic reticulum stress ATF6 pathway by regulating the expression of miRNA-199a-5p in cardiac toxicity.

METHODS

This project established a model of primary cardiomyocytes derived from neonatal rats and treated them with 5-FU in vitro. The expression of miRNA-199a-5p and its regulation were explored in vitro and in vivo.

RESULTS

5-FU decreases the expression of miRNA-199a-5p in cardiomyocytes, activates the endoplasmic reticulum stress ATF6 pathway, and increases the expression of GRP78 and ATF6, affecting the function of cardiomyocytes, and induces cardiac toxicity. The rescue assay further confirmed that miRNA-199a-5p supplementation can reduce the cardiotoxicity caused by 5-FU, and its protective effect on cardiomyocytes depends on the downregulation of the endoplasmic reticulum ATF6 signaling pathway.

CONCLUSIONS

5-FU can down-regulate expression of miRNA-199a-5p, then activate the endoplasmic reticulum stress ATF6 pathway, increase the expression of GRP78 and ATF6, affect the function of cardiomyocytes, and induce cardiac toxicity.

Long-term Musculoskeletal Consequences of Chemotherapy in Pediatric Mice

Thanks to recent progress in cancer research, most children treated for cancer survive into adulthood. Nevertheless, the long-term consequences of anticancer agents are understudied, especially in the pediatric population. We and others have shown that routinely administered chemotherapeutics drive musculoskeletal alterations, which contribute to increased treatment-related toxicity and long-term morbidity. Yet, the nature and scope of these enduring musculoskeletal defects following anticancer treatments and whether they can potentially impact growth and quality of life in young individuals remain to be elucidated. Here, we aimed at investigating the persistent musculoskeletal consequences of chemotherapy in young (pediatric) mice. Four-week-old male mice were administered a combination of 5-FU, leucovorin, irinotecan (a.k.a., Folfiri) or the vehicle for up to 5 wk. At time of sacrifice, skeletal muscle, bones, and other tissues were collected, processed, and stored for further analyses. In another set of experiments, chemotherapy-treated mice were monitored for up to 4 wk after cessation of treatment. Overall, the growth rate was significantly slower in the chemotherapy-treated animals, resulting in diminished lean and fat mass, as well as significantly smaller skeletal muscles. Interestingly, 4 wk after cessation of the treatment, the animals exposed to chemotherapy showed persistent musculoskeletal defects, including muscle innervation deficits and abnormal mitochondrial homeostasis. Altogether, our data support that anticancer treatments may lead to long-lasting musculoskeletal complications in actively growing pediatric mice and support the need for further studies to determine the mechanisms responsible for these complications, so that new therapies to prevent or diminish chemotherapy-related toxicities can be identified.

Therapeutic benefit of melatonin in 5-fluorouracil-induced renal and hepatic injury

Nephrotoxicity and hepatotoxicity include increased oxidative stress and apoptosis; as a result, liver and kidney damage are related to its pathogenesis. These are significant side effects caused in cancer patients treated with 5-FU. In the research, 25 rats were divided into five groups, including control, 5-FU and 5-FU + 2.5, 5 and 10 mg/kg melatonin (MEL), and the protective impact of MEL against 5-FU-induced hepatorenal damage in rats was investigated. 5-FU caused significant harm, resulting in severe renal failure and histopathological changes. It also increased BUN, creatinine and hepatic function markers levels while decreasing superoxide dismutase and glutathione peroxidase activity. Additionally, 5-FU led to a notable increase in malondialdehyde content. However, MEL co-administration to rats reversed most biochemical and histologic effects. In the control and MEL + 5-FU groups, the values were comparable. The doses of MEL treatment had a significant positive impact on 5-FU-induced oxidative stress, apoptosis, lipid peroxidation and kidney damage. Our data concluded that MEL has an ameliorative effect on hepatorenal damage caused by 5-FU.

Dihydromyricetin reverses capecitabine-induced peripheral myelin dysfunction through modulation of oxidative stress

Previous clinical reports have shown that capecitabine, an oral prodrug of 5-fluorouracil (5-Fu), can induce peripheral neuropathy, resulting in numbness, paresthesia and hypoesthesia. However, the mechanism through which capecitabine causes peripheral nerve injury remains unclear. Here, we demonstrate that systemic administration of capecitabine leads to myelin abnormalities in the peripheral nerves of mice, which are possibly attributed to the death of Schwann cells, the myelinating cells in the peripheral nervous system. Furthermore, our results show that 5-Fu induces significant oxidative stress in Schwann cells by inhibiting the expression of the anti-oxidative protein DJ-1, leading to a decrease in Schwann cell markers. We found that the anti-oxidant dihydromyricetin (DMY) reverses 5-Fu-induced Schwann cell death and oxidative stress and alleviates capecitabine-induced myelin abnormalities. Taken together, our data indicate that capecitabine induces peripheral myelin dysfunction by regulating DJ-1-mediated oxidative stress in Schwann cells and reveal DMY as a potential therapeutic strategy for capecitabine-induced peripheral neuropathy.

The hepatotoxicity of γ-radiation synthesized 5-fluorouracil nanogel versus 5-fluorouracil in rats model

INTRODUCTION

The clinical use of 5-fluorouracil (5-FU), a routinely used chemotherapy medication, has a deleterious impact on the liver. Therefore, it is necessary to find a less harmful alternative to minimize liver damage. This study was designed to see how 5-fluorouracil nanogel influenced 5-FU-induced liver damage in rats.

METHODS

To induce liver damage, male albino rats were injected intraperitoneally with 5-FU (12.5 mg/kg) three doses/week for 1 month. The histopathological examination together with measuring the activities of serum alanine and aspartate aminotransferase enzymes (ALT and AST) were used to evaluate the severity of liver damage besides, hepatic oxidative stress and antioxidant markers were also measured. The hepatic gene expression of heme oxygenase-1 (HO-1), nuclear factor erythroid 2-related factor 2 (Nrf2) and its inhibitor Kelch-like ECH-associated protein-1(Keap-1) in addition to hepatic inflammatory mediators including tumor necrosis factor-α (TNF- α) and interleukins (IL-1β, IL-6) were detected.

RESULTS

5-Fu nanogel effectively attenuated 5-FU-induced liver injury by improving the hepatic structure and function (ALT and AST) besides the suppression of the hepatic inflammatory mediators (TNF- α, IL-1β and IL-6). Additionally, 5-FU nanogel alleviated the impaired redox status and restored the antioxidant system via maintaining the cellular homeostasis Keap-1/Nrf2/HO-1 pathway.

CONCLUSION

Consequently, 5-Fu nanogel exhibited lower liver toxicity compared to 5-FU, likely due to the alleviation of hepatic inflammation and the regulation of the cellular redox pathway.

Hazard assessment of antineoplastic drugs and metabolites using cytotoxicity and genotoxicity assays

Antineoplastic drugs are among the most toxic pharmaceuticals. Their release into the aquatic ecosystems has been reported, giving rise to concerns about the adverse effects, including cytotoxicity and genotoxicity, that they may have on exposed organisms. In this study, we analyzed the cytotoxicity and genotoxicity of 5-fluorouracil (5-FU) and its metabolite alpha-fluoro-beta-alanine (3-NH2-F); gemcitabine (GEM) and its metabolite 2'-deoxy-2',2'-difluorouridine (2-DOH-DiF); as well as cyclophosphamide (CP) on the HepG2 cell line. Drug concentrations were based on those previously observed in the effluent of a major cancer hospital in Brazil. The study found that GEM, 2-DOH-DiF and 5-FU resulted in reduced cell viability. No reduction in cell viability was observed for CP and 3-NH2-F. Genotoxic assessment revealed damage in the form of nucleoplasmic bridges for CP and 3-NH2-F. The tested concentrations of all compounds resulted in significantly increased MNi and NBUDs. The results showed that these compounds induced cytotoxic and genotoxic effects in HepG2 cells at concentrations found in the environment. To the best of our knowledge, this study is the first to report on the cytogenotoxic impacts of the metabolites 3-NH2-F and 2-DOH-DiF in HepG2 cells. These findings may help in the development of public policies that could minimize potential environmental contamination.

Achyrocline B (3,5 dihydroxy-6,7,8-trimethoxyflavone) synergizes with 5-fluorouracil allowing for dose reduction and reduced off-target toxicity in the treatment of colonic and pancreatic cancers

Surgically unresectable colorectal and pancreatic carcinomas have a high rate of mortality as current therapeutic options are limited. One common chemotherapeutic used to broadly treat both cancers is 5-flurouracil (5-Fu); however, treatment serves only to slow progression of the disease and comes with many side effects due to 5-Fu's intrinsic toxicity. Thus, strategies to decrease the dose of 5-Fu utilized therapeutically as well as reduce 5-Fu's off-target toxicity are paramount. Using cell models of colorectal and pancreatic cancers, we show that cotreatment with Achyrocline B (3,5 dihydroxy-6,7,8-trimethoxyflavone, AcB), a natural flavone from Achyrocline bogotensis, allows for four-fold reduction in 5-Fu dosage without loss of efficacy. We further show that the action of AcB is due to continued cell cycle progression despite 5-Fu pressure to synchronize at the G1/S threshold. In addition to AcB's effect on cancer cells, we found that AcB can directly reduce toxicity of 5-Fu in cells mimicking non-cancerous tissues. These in vitro results are then supported by xenograft modeling. AcB was shown to increase apoptosis in tumors leading to degeneration of the outer tumoral boundary. Furthermore, in 5-Fu treated animals it was found that AcB provided protection to the intestinal tract as indicated by preserved histological and immunohistochemical features. These results show promise for a new adjuvant therapy for colorectal and pancreatic carcinomas that not only reduces tumor progression, but more importantly has the potential to improve patient quality of life.

A dynamic model of the intestinal epithelium integrates multiple sources of preclinical data and enables clinical translation of drug-induced toxicity

We have built a quantitative systems toxicology modeling framework focused on the early prediction of oncotherapeutic-induced clinical intestinal adverse effects. The model describes stem and progenitor cell dynamics in the small intestinal epithelium and integrates heterogeneous epithelial-related processes, such as transcriptional profiles, citrulline kinetics, and probability of diarrhea. We fitted a mouse-specific version of the model to quantify doxorubicin and 5-fluorouracil (5-FU)-induced toxicity, which included pharmacokinetics and 5-FU metabolism and assumed that both drugs led to cell cycle arrest and apoptosis in stem cells and proliferative progenitors. The model successfully recapitulated observations in mice regarding dose-dependent disruption of proliferation which could lead to villus shortening, decrease of circulating citrulline, increased diarrhea risk, and transcriptional induction of the p53 pathway. Using a human-specific epithelial model, we translated the cytotoxic activity of doxorubicin and 5-FU quantified in mice into human intestinal injury and predicted with accuracy clinical diarrhea incidence. However, for gefitinib, a specific-molecularly targeted therapy, the mice failed to reproduce epithelial toxicity at exposures much higher than those associated with clinical diarrhea. This indicates that, regardless of the translational modeling approach, preclinical experimental settings have to be suitable to quantify drug-induced clinical toxicity with precision at the structural scale of the model. Our work demonstrates the usefulness of translational models at early stages of the drug development pipeline to predict clinical toxicity and highlights the importance of understanding cross-settings differences in toxicity when building these approaches.

Melatonin protected against kidney impairment induced by 5-fluorouracil in mice

The utility of 5-fluorouracil (5-FU) as a successful chemotherapeutic drug for several cancers is limited by the induction of kidney injury and dysfunction due to redox imbalance, inflammation, and apoptosis. Meanwhile, melatonin (MLT) is a potent antioxidant and anti-inflammatory natural compound with a wide safety range. The current study aimed to investigate MLT's protective effect against 5-FU-induced kidney impairment. Male mice were given multiple doses of 5-FU at 25 and 100 mg/kg, as well as MLT at 20 mg/kg. MLT treatment alleviated the toxic effect of 5-FU by normalizing blood urea and creatinine levels and preserving the histological structure, indicating MLT's nephroprotective ability. This is accompanied by body weight maintenance, an increase in survival percentage, and preserved hematological parameters in comparison to the 5-FU-treated mice. MLT's renoprotective effect was explained by improvements in C-reactive protein, IL-6, and caspase-3 in kidney tissue, indicating MLT's anti-inflammatory and antiapoptotic ability. Furthermore, MLT inhibited 5-FU-induced lipid peroxidation by maintaining the activity of superoxide dismutase and catalase, as well as glutathione levels in kidney tissue from mice treated with both doses of 5-FU. The current findings show that MLT has a novel protective effect against 5-FU-induced renal injury and renal impairment.

The role of Hippophae rhamnoides L. on 5-fluorouracil-ınduced oral mucositis in rats

Current study aimed to research the effect of Hippophae rhamnoides (HRE) on potantial oral oxidative and inflammatory damage of 5-FU in rats. The rats were assigned to three groups; healthy (HG), 5-FU 100mg/kg (FUG) and HRE 50mg/kg +5-FU 100mg/kg (HRFU). The 5-FU was injected in the FUG group intraperitoneally. The HRFU was injected 5-FU at 100mg/kg IP one hour after the 50mg/kg HRE was given orally. Olive oil was used as a solvent for the HG. HRE was given to the rats three times a day for ten days. 5-FU was given one dose on the 1st, 3rd and 5th days. On the 10th day, the tissues removed from the animals were euthanized with high-dose anaesthesia and were macroscopically examined. The levels of the oxidant, antioxidant and proinflammatory cytokines were investigated.It was seen that HRE alleviated the symptoms of severe mucositis by antagonizing the effects of 5-FU on oxidant, antioxidant and proinflammatory cytokines such as malondialdehyde, total glutathione, superoxide dismutase, catalase, nuclear factor kappa-B and interleukin-6 in inner cheek and tongue tissue. These results recommend that HRE may be benefical in the cure of 5-FU-associated oral mucositis.

The therapeutic effect of silibinin against 5-fluorouracil-induced ovarian toxicity in rats

5-Fluorouracil (5-FU) is a fluoropyrimidine group antineoplastic drug with antimetabolite properties and ovotoxicity is one of the most important side effects. Silibinin (SLB) is a natural compound that is used worldwide and stands out with its antioxidant and anti-inflammatory properties. The aim of this study was to evaluate the therapeutic effect of SLB in 5-FU-induced ovototoxicity using biochemical and histological analysis. This study was carried out in five main groups containing six rats in each group: control, SLB (5 mg/kg), 5-FU (100 mg/kg), 5-FU + SLB (2.5 mg/kg), and 5-FU + SLB (5 mg/kg). The levels of ovarian malondialdehyde (MDA), total oxidant status (TOS), total antioxidant status (TAS), superoxide dismutase (SOD), catalase (CAT), 8-hydroxy-2'-deoxyguanosine (8-OHdG), tumor necrosis factor-alpha (TNF-α), myeloperoxidase (MPO), and caspase-3 were determined using spectrophotometric methods. Hematoxylin and eosin staining method was employed for histopathological examination. MDA, TOS, 8-OHdG, TNF-α, MPO, and caspase-3 levels in 5-FU group were significantly increased compared with the control group, while the levels of TAS, SOD, and CAT were decreased (p < 0.05). SLB treatments statistically significantly restored this damage in a dose-dependent manner (p < 0.05). Although vascular congestion, edema, hemorrhage, follicular degeneration, and leukocyte infiltration were significantly higher in the 5-FU group compared with the control group, SLB treatments also statistically significantly restored these damages (p < 0.05). In conclusion, SLB has a therapeutic effect on the ovarian damage induced by 5-FU via decreasing the levels of oxidative stress, inflammation, and apoptosis. It may be helpful to consider the usefulness of SLB as an adjuvant therapy to counteract the side effects of chemotherapy.

Thymoquinone protects against 5-Fluorouracil-induced mucositis by NF-κβ and HIF-1 mechanisms in mice

Mucositis is among the most common side effects of 5-Fluorouracil (5-FU) and other cancer therapeutic drugs. Thymoquinone (TQ), a bioactive constituent extracted from Nigella sativa, has antioxidant and anti-inflammatory properties and can modify acute gastrointestinal injury. To investigate the effects of TQ on mucositis induced by 5-FU, studied animals were divided into four groups: control, 5-FU unit dose (300 mg/kg) to cause oral and intestinal mucositis (OM and IM), TQ (2.5 mg/kg) and TQ (2.5 mg/kg) plus 5-FU. Due to The molecular mechanisms, it was confirmed that the expression of NF-κβ and HIF-1 increases in OM. The serum levels of malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD), as well as pathological parameters, were assessed. Based on our results, the nuclear factor-kappa β gene expression in the tongue was downregulated significantly in the 5-FU + TQ compared to the 5-FU. TQ treatment can diminish MDA, and a reduction in oxidative stress was shown. TQ could also reduce the severity of tissue destruction and damaging effects induced by 5-FU on the tongue and intestine. We also observed lower villus length and width in the intestine of the 5-FU group compared to the control group. According to our research's pathological, biochemical, and molecular results, treatment with TQ as an anti-inflammatory and antioxidant compound may be the potential to improve and treat 5-FU-induced OM and IM, and TQ could be used against cancer treatment drugs and exhibit fewer adverse effects.

Antineoplastic drugs in environmentally relevant concentrations cause endocrine disruption and testicular dysfunction in experimental conditions

5-fluorouracil (5-FU) and methotrexate (MTX) are among the most widely consumed antineoplastic drugs worldwide. These drugs are known as emerging pollutants, once after consumption are excreted by feces and/or urine in a mixture of compounds and metabolites, entering the aquatic environment due to low efficiency in drug removal by effluent treatment plants. Considering that these substances may interact with the DNA, causing metabolic and morphological changes, leading to cell death, the present study aimed to investigate the potential impact of a long-term exposure to these antineoplastic drugs in environmentally relevant concentrations, on testicular morphophysiology of rats. Male Wistar rats (70 days old) were distributed into 4 groups (n = 10 / group): control, received only vehicle; MTX, received methotrexate at 10ngL-1 in drinking water; 5-FU received 5-fluorouracil at 10ngL-1 in drinking water; and MTX+ 5FU, received the combination of MTX and 5-FU at 10ngL-1 each. The treatment period was from postnatal day (PND)70 to PND160, when the animals were euthanized for evaluation of testicular toxicity and changes in endocrine signaling. In these experimental conditions, both drugs acted as endocrine disruptors causing cytotoxic effects in the testes of exposed rats, altering the structural pattern of seminiferous tubules and leading to oxidative stress even at environmental concentrations.

Assessing the impact of antineoplastic drugs in the aquatic environment: State of the art and future perspective for freshwater organisms

Since the late 70s, the continuous pharmaceuticals` input into the environment has raised concerns regarding the eventual risk posed by such compounds to human and environmental health. A major group of pharmaceuticals in terms of environmental impact are the antineoplastic agents (AAs). Herein, we followed a systematic review method to retrieve antineoplastic agents (AAs') ecotoxicological information regarding freshwater species. In this analysis, data from diverse taxonomic groups, from microorganisms to vertebrate species, looked at different levels of biological organization, including cell lines. Furthermore, this review gathers ecotoxicological parameters (EC₅₀ and LC₅₀) for imatinib (IM), cisplatin (CisPt), and 5-fluorouracil (5-FU) in species sensitivity distribution (SSD) curves and estimates the hazard concentration (HC₅) considering the protection of 95% of the ecological community. Lastly, we suggest how we can improve AAs' Environmental Risk Assessment (ERA), considering potential adoptable toxicity endpoints, test duration, AAs metabolites testing, and AAs mixture exposure.

Increased Expression of Hepatic Stearoyl-CoA Desaturase (SCD)-1 and Depletion of Eicosapentaenoic Acid (EPA) Content following Cytotoxic Cancer Therapy Are Reversed by Dietary Fish Oil

Cancer treatment evokes impediments to liver metabolism that culminate in fatty liver. This study determined hepatic fatty acid composition and expression of genes and mediators involved in lipid metabolism following chemotherapy treatment. Female rats bearing the Ward colon tumor were administered Irinotecan (CPT-11) +5-fluorouracil (5-FU) and maintained on a control diet or a diet containing eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) (2.3 g/100 g fish oil). Healthy animals provided with a control diet served as a reference group. Livers were collected one week after chemotherapy. Triacylglycerol (TG), phospholipid (PL), ten lipid metabolism genes, leptin, and IL-4 were measured. Chemotherapy increased TG content and reduced EPA content in the liver. Expression of SCD1 was upregulated by chemotherapy, while dietary fish oil downregulated its expression. Dietary fish oil down-regulated expression of the fatty acid synthesis gene FASN, while restoring the long chain fatty acid converting genes FADS2 and ELOVL2, and genes involved in mitochondrial β-oxidation (CPT1α) and lipid transport (MTTP1), to values similar to reference animals. Neither leptin nor IL-4 were affected by chemotherapy or diet. Depletion of EPA is associated with pathways evoking enhanced TG accumulation in the liver. Restoring EPA through diet may pose a dietary strategy to attenuate chemotherapy-associated impediments in liver fatty acid metabolism.

Preparation and pharmaceutical properties of Hangeshashinto oral ointment and its safety and efficacy in Syrian hamsters with 5-fluorouracil-induced oral mucositis

Chemotherapy-induced oral mucositis (COM) is a common adverse effect of cancer chemotherapy. Several clinical studies reported that repetitive use of mouthwashes containing 2.5-6.25% Hangeshashinto (HST), a Kampo formula, relieves COM, but the effect is insufficient. To solve this problem, we produced an oral ointment of 12% HST extract (considered quantitatively equivalent to 20% commercially available HST), which will increase the local concentrations of its active ingredients and prolong the contact time with COM. In this study, we evaluated the pharmaceutical properties (spreadability and stability) of HST oral ointment. In addition, its safety (oral mucosal irritation) and therapeutic effects on 5-fluorouracil-induced oral mucositis were evaluated in male Syrian hamsters. The HST ointment showed good spreadability and stability for more than 8 weeks at 4 °C. In the oral mucosal irritation test, topical application of HST ointment (0.2 g) three times per day for 14 days had no adverse effect on the oral mucosa of hamsters. In hamsters treated with 5-fluorouracil (60 mg/kg) twice, COM was induced by a submucosal injection of 5% acetic acid into the cheek pouch. When HST ointment (50 µg) was topically applied to the mucositis area once per day for 12 days, the area and macroscopic score of mucositis were significantly decreased, and the depth of the wound tended to be reduced compared with the lactose ointment-treated control animals. These findings suggest that HST oral ointment shows good properties in spreadability, stability, and safety, and elicits a therapeutic effect in an animal model of COM.

5-Flourouracil-induced toxicity in both male and female reproductive systems: A narrative review

The chemotherapeutic drug 5-flourouracil (5FU) is frequently used to treat a wide range of solid malignant tumors, such as colorectal, pancreatic, gastric, breast, and head and neck cancers. Its antitumoral effects are achieved by interfering with the synthesis of RNA and DNA and by inhibiting thymidylate synthase in both malignant and non-malignant cells. Therefore, it can be responsible for severe toxicities in crucial body organs, including heart, liver, kidney, and reproductive system. Given the fact that 5FU-induced reproductive toxicity may limit the clinical application of this drug, in this study, we aimed to discuss the main locations and mechanisms of the 5FU-induced reproductive toxicity. Initially, we discussed the impact of 5FU on the male reproductive system, which leads to damage of the seminiferous epithelial cells and the development of vacuoles in Sertoli cells. Although no noticeable changes occur at the histopathological level, there is a decrease in the weight of the prostate. Additionally, 5FU causes significant abnormalities in spermatogenesis, including germ cell shedding, spermatid halo formation, polynucleated giant cells, and decreased sperm count. Finally, in females, 5FU-induced reproductive toxicity is characterized by the presence of atretic secondary and antral follicles with reduced numbers of growing follicles, ovarian weight, and maturity impairment.

Amelioration of 5-Fluorouracil Induced Nephrotoxicity by Acacia catechu through Overcoming Oxidative Damage and Inflammation in Wistar Rats

AIM

The research intended to explore the possible nephroprotective potential of the ethyl acetate fraction derived from Acacia catechu leaves against nephrotoxicity brought about by 5-fluorouracil (5-FU) in Wistar rats.

BACKGROUND

While possessing strong anticancer properties, 5-FU is hindered in its therapeutic application due to significant organ toxicity linked to elevated oxidative stress and inflammation.

OBJECTIVE

The study is undertaken to conduct an analysis of the ethyl acetate fraction of A. catechu leaves both in terms of quality and quantity, examining its impact on different biochemical and histopathological parameters within the context of 5-FU-induced renal damage in rats and elucidation of the mechanism behind the observed outcomes.

METHODOLOGY

Intraperitoneal injection of 5-FU at a dosage of 20 mg/kg/day over 5 days was given to induce nephrotoxicity in rats. The evaluation of nephrotoxicity involved quantifying serum creatinine, urea, uric acid, and electrolyte concentrations. Furthermore, superoxide dismutase, catalase antioxidant enzymes, and TNF-α concentration in serum were also measured.

RESULTS

5-FU injection led to the initiation of oxidative stress within the kidneys, leading to modifications in renal biomarkers (including serum creatinine, urea, uric acid, and Na+, K+ levels), and a reduction in antioxidant enzymes namely superoxide dismutase and catalase. Notably, the presence of the inflammatory cytokine TNF-α was significantly elevated due to 5-FU. Microscopic examination of renal tissue revealed tubular degeneration and congestion. However, treatment involving the ethyl acetate fraction derived from A. catechu leaves effectively and dose-dependently reversed the changes observed in renal biomarkers, renal antioxidant enzymes, inflammatory mediators, and histopathological features, bringing them closer to normal conditions. The observed recuperative impact was mainly attributed to the antioxidant and antiinflammatory properties of the fraction.

CONCLUSION

The ethyl acetate fraction of A. catechu leaves exhibited a mitigating influence on the renal impairment caused by 5-FU, showcasing its potential as a nephroprotective agent capable of preventing and ameliorating 5-FU-induced nephrotoxicity.

Assessing the effects of the cytostatic drug 5-Fluorouracil alone and in a mixture of emerging contaminants on the mussel Mytilus galloprovincialis

The assessment of contaminants of emerging concern, alone and in mixtures, and their effects on marine biota requires attention. 5-Fluorouracil is a cytostatic category 3 anti-cancer medication (IARC) that is used to treat a variety of cancers, including colon, pancreatic, and breast cancer. In the presence of other pollutants, this pharmaceutical can interact and form mixtures of contaminants, such as adhering to plastics and interaction with metal nanoparticles. This study aimed to comprehend the effects of 5-Fluorouracil (5FU; 10 ng/L) and a mixture of emerging contaminants (Mix): silver nanoparticles (nAg; 20 nm; 10 μg/L), polystyrene nanoparticles (nPS; 50 nm; 10 μg/L) and 5FU (10 ng/L), in an in vivo (21 days) exposure of the mussel Mytilus galloprovincialis. A multibiomarker approach namely genotoxicity, the antioxidant defence system (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx), glutathione - S - transferases (GST) activities), and oxidative damage (LPO) was used to assess the effects in gills and digestive gland of mussels. Both treatments cause genotoxicity in mussel's haemolymph, and antagonism between contaminants was observed in the Mix. Genotoxicity observed confirms 5FU's mode of action (MoA) by DNA damage. The antioxidant defence system of mussels exposed to 5FU kicked in and counter balanced ROS generated during the exposure, though the same was not seen in Mix-exposed mussels. Mussels were able to withstand the effects of the single compound but not the effects of the Mix. For oxidative stress and damage, the interactions of the components of the mixture have a synergistic effect.

The reproductive effects of the cancer chemotherapy agent, Carmofur, on Daphnia magna are mediated by its metabolite, 5-Fluorouracil

Carmofur is an antineoplastic agent that inhibits ceramidase, a key enzyme in the sphingolipid pathway. Previous research suggests carmofur represses reproductive maturity in Daphnia magna. The purpose of this experiment was to confirm carmofur's effects on fecundity and reproductive maturity over two generations. A chronic toxicity test found reproductive maturity was delayed from 9 to 19 days by 0.80 μM carmofur with a 99.7% drop in reproduction, probably caused by delayed ovarian development. Second generation effects were even greater with 0% reproductive success at 0.40 μM. To our surprise, carmofur was not measured in the media by HPLC 24 h after exposure. Previous research indicated that carmofur is unstable in water and hydrolyzed into 5-fluorouracil (5-FU). Therefore, the chronic toxicity study was repeated with 5-FU and similar effects on reproductive maturity were observed at similar concentrations despite very different acute toxicities (48 h carmofur LC50 = 1.93 μM; 5-FU LC50 = 207 μM). 5-FU delayed reproductive maturity from 9 to 21 days with a 71.12% drop in reproduction at 0.80 μM and greater effects in the 2^nd generation similar to carmofur. 5-FU was found stable in aquatic media and HPLC confirmed 5-FU was hydrolyzed from carmofur within 24 h. In conclusion, carmofur and 5-FU reduce fecundity because they delay reproductive maturity and ovarian development in Daphnia magna. We conclude that the reproductive effects observed after carmofur treatment are primarily mediated by its breakdown product, 5-FU. This further underscores the importance of measuring chemical concentrations and evaluating chemical metabolism and decomposition when determining toxicity, especially of chemotherapeutic agents.Clinical trials registration Not applicable.

Role of Platelet-activating factor and HO-1 in mediating the protective effect of rupatadine against 5-fluorouracil-induced hepatotoxicity in rats

5-fluorouracil (5-FU) is a widely used chemotherapeutic drug, but its hepatotoxicity challenges its clinical use. Thus, searching for a hepatoprotective agent is highly required to prevent the accompanied hepatic hazards. The current study aimed to investigate the potential benefit and mechanisms of action of rupatadine (RU), a Platelet-activating factor (PAF) antagonist, in the prevention of 5-FU-related hepatotoxicity in rats. Hepatotoxicity was developed in male albino rats by a single 5-FU (150 mg/kg) intra-peritoneal injection on the 7th day of the experiment. RU (3 mg/kg/day) was orally administrated to the rodents for 10 days. Hepatic toxicity was assessed by measuring both liver and body weights, serum alanine aminotransferase and aspartate aminotransferase (ALT and AST), hepatic oxidative stress parameters (malondialdehyde (MDA), nitric oxide levels (NOx), reduced glutathione (GSH), superoxide dismutase (SOD)), and heme oxygenase-1 (HO-1). Inflammatory markers expressions (inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNFα), interleukins; IL-1B, IL-6), the apoptotic marker (caspase-3), and PAF were measured in the hepatic tissue. 5-FU-induced hepatotoxicity was proved by the biochemical along with histopathological assessments. RU ameliorated 5-FU-induced liver damage as proved by the improved serum ALT, AST, and hepatic oxidative stress parameters, the attenuated expression of hepatic pro-inflammatory cytokines and PAF, and the up-regulation of HO-1. Therefore, it can be concluded that RU pretreatment exerted a hepatoprotective effect against 5-FU-induced liver damage through both its powerful anti-inflammatory, antioxidant, and anti-apoptotic effect.