Lycopene alleviates 5-fluorouracil-induced nephrotoxicity by modulating PPAR-γ, Nrf2/HO-1, and NF-κB/TNF-α/IL-6 signals

Abstract

5-Fluorouracil (5-FU) is one of the most used anticancer drugs. However, its nephrotoxicity-associated drawback is of clinical concern. Lycopene (LYC) is a red carotenoid with remarkable anti-inflammatory and anti-oxidative properties. In this study, rats were divided randomly into five groups: control, lycopene (10 mg) (10 mg/kg/day; P.O), 5-FU (30 mg/kg/day; i.p.), Lycopene (5 mg) + 5-FU (5 mg/kg + 30 mg/kg/day), and lycopene (10 mg) + 5-FU (10 mg/kg + 30 mg/kg/day). LYC attenuated the loss of renal function induced by 5-FU in a dose-dependent manner. Rats co-treated with LYC had lower serum urea, creatinine, uric acid and KIM-1 levels, and a higher serum albumin level than those receiving 5-FU alone. Furthermore, co-treatment with the high dose of LYC maintained renal oxidant–antioxidant balance by ameliorating/preventing the loss of antioxidants and the elevation of malondialdehyde. Rats treated with 5-FU had markedly lower renal levels of PPAR-gamma, HO-1, Nfr2, and Il-10 and higher levels of NF-kB, TNF-alpha, and IL6 compared to the control rats. Co-treatment with LYC attenuated the reduction in PPAR-gamma, HO-1, Nfr2, and IL-10 levels and moderated the elevated levels of NF-kB, TNF-alpha, and IL-6. The kidneys from rats co-treated with lycopene (10 mg) + 5-FU did not show the degenerative changes in the glomerular tufts and tubules observed for the rats treated with 5-FU alone. In conclusion, LYC is a promising therapeutic strategy for attenuating 5-FU-induced nephrotoxicity through the restoration of antioxidant activities and inhibition of inflammatory responses by modulating PPAR-γ, Nrf2/HO-1, and NF-κB/TNF-α/IL-6, signals.

1. Introduction

One widely used anticancer agent is 5-fluorouracil (5-FU), which treats various malignancies, such as breast, liver, pancreatic, esophageal, gastric, colorectal, head, and neck cancers [1,2]. The main mechanism of 5-FU is inhibiting cancer cell growth and proliferation by inhibiting thymidylate synthase, which is required for thymine nucleotide synthesis [3]. Regrettably, the clinical application of 5-FU is limited because of its adverse actions. 5-FU-induced nephrotoxicity is one of the major side effects [4].

Peroxisome proliferator-activated receptor gamma (PPAR-γ) and nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1(HO-1) signals are the key cytoprotective pathways in oxidative stress and play a critical role in kidney protection against diseases [5,6]. On the other side, nuclear factor kappa-B (NF-κB), the strategic controller of inflammation, and the inflammatory cytokines; tumor necrosis factor (TNF)-α and interleukin (IL)-6 play significant roles in inflammation in various illnesses, and they have a substantial role in the development of renal injury [7]. In contrast, IL-10 has a cytoprotective anti-inflammatory effect and has previously been reported to attenuate renal injury in different animal models [8–10].

Interestingly, many phytochemicals have medical benefits and have been used as therapeutic agents for different diseases [11,12]. Additionally, considerable studies investigated that phytochemicals have an effective role in attenuating 5-FU-induced renal injury [13–16]. Lycopene (LYC) is a red carotenoid that exists naturally in rich content in tomatoes, watermelons, bananas, grapes, oranges, papayas, and other fruits [17]. LYC possesses antioxidant, anti-inflammatory, and anticancer effects [18–21]. LYC suppresses the cytotoxicity and cell migration when used as an adjuvant with 5-FU in human colon cancer [22] as well as anti-oxidative and anti-inflammatory activities against 5-FU-induced cytotoxicity in colorectal cancer cell line (Caco2) [23]. LYC inhibits NK-_KB signaling and induces apoptosis in pancreatic cancer cells [24]. Also, it is reported that LYC protects against chemicals and toxins-induced toxicity; besides, there is no history of toxicity due to fruit and vegetable-containing LYC [25,26]. LYC protects adriamycin and cyclosporine A-induced testicular toxicities in rats (Ateşşahin et al. 2006; Türk et al. 2007) as well as radiation- and bisphenol A-induced hepatic toxicities in rats [27,28]. It is reported that LYC has a renal protective effect against drug-induced kidney injury, that is, against oxidative kidney damage associated with combined use of isoniazid and rifampicin in rats, cisplatin-induced nephrotoxicity, and methotrexate-induced functional alterations of the Madin-Darby kidney cells [29–31]. These beneficial effects of LYC make it a great candidate for attenuation of nephrotoxicity induced by 5-FU side effects. This study aimed to investigate the possible reno-protective effect of LYC against 5-FU-induced injury and validate the impact of PPAR-γ, Nrf2/HO-1, and NF-κB/TNF-α/IL-6 signals in renal protection.

2. Materials and methods

2.1. Animals

Thirty male rats (average weight 150–200 gm) were kept in cages for 2 weeks to acclimate to laboratory conditions. They were purchased and kept in an animal house with 50% humidity, 25 Celsius temperature, and a 12-h dark:12-h light cycle. They were supplied with plenty of standard food and water. The Institutional Review Board (IRB) approved the experiment ethically at King Abdullah bin Abdulaziz University Hospital, Riyadh, KSA (HA-01-R-104).

2.2. Experimental design

Animals were randomly assigned to five groups (each containing six rats) by a technician unaware of the experimental group’s identity. During the experiment period (10 days), rats were used to administer one of the following regimens daily (Table 1).

Table 1.

Experimental design.

Groups	Dosage	Treatment and duration
Normal (control) group	Vehicle	Throughout the experiment period
Lycopene (10 mg) group	LYC (10 mg/kg/day) by gavage	Throughout the experiment period (10 days)
5-FU group	5-FU (30 mg/kg/day; intraperitoneal injection (i.p.)	Five consecutive days started on the 6th day of the experiment.
Lycopene (5 mg) + 5-FU group	LYC (5 mg/kg/day) by gavage + 5-FU (30 mg/kg/day; i.p.)	LYC is in the lycopene group, but the dose is 5 mg + 5-FU as in the 5-FU group.
Lycopene (10 mg) + 5-FU group	LYC (10 mg/kg/day) by gavage + 5-FU (30 mg/kg/day; i.p.)	LYC as in the lycopene (10 mg) group + 5-FU as in the 5-FU group.

The experimental regimen and dosage of 5-FU were based on previous work on 5-FU-induced nephrotoxicity in rats. It was given by intraperitoneal injection on the 6th day of the experiment (after 5 days from the start of LYC gavage) for 5 consecutive days [32–34]. Also, the dosage of LYC is based on previous works that found a 5 mg/kg dose effective as an antioxidant anti-inflammatory in rat models [35,36]. During the experimental period, LYC was given in lycopene (10 mg), lycopene (5 mg) + 5-FU, and lycopene (10 mg) + 5-FU groups for 10 days.

At the end of the experiment, all rats were sacrificed, and the two kidneys were divided into equal halves; one each was homogenized in phosphate buffer saline to yield a 10% w/v homogenate for the biochemical tests. The homogenate was kept at 4 °C for 15 min before being centrifuged at 1200 g at 4 °C, and the supernatant was kept at −80 °C until the assays were performed. The other halves were processed for histological and immunohistochemical examinations.

2.3. Kidney function biomarkers

Urea (Cat. No. UR-21-10), creatinine (Cat. No. CR-12-50), uric (Cat. No. UA-21-20), and albumin (albumin-FH10) levels in serum were measured using commercial vendor kits (Spectrum Diagnostics Company, Obour City, Cairo, Egypt) to evaluate the renal functions. Furthermore, according to the vendor’s instructions, a quantitative bioassay of the kidney injury molecule-1 (KIM-1) (cat. No. E-EL-R3019 Elabscience, Houston, Texas, USA) was measured in real tissues using ELISA kits.

2.4. Assessment of renal oxidative stress biomarkers

Assessment of renal malondialdehyde (MDA) (cat. No. MD-25-29) and reduced glutathione (GSH) (cat. No. GR-25-11) were done by methods previously described by Mihara and Uchiyama [37] and Ellman [38], respectively. Renal enzymatic activities of superoxide dismutase (SOD) (cat. No. SD-25-21), glutathione S-transferases (GST) (cat. No. GT-25-19), and glutathione peroxidase (GPx) (gpx1-kit_ka0882) were assessed using commercial kits (Spectrum Diagnostics Company, Egypt). The methods were previously established by Keen et al. [39], Marklund and Marklund (1974) [40], and Fathy and Drees [41].

2.5. Histopathological examination

Kidney specimens were fixed in 10% buffered formalin and dehydrated in upgraded serial concentrations of ethyl alcohol. The specimens were cleared in xylene and then embedded in paraffin wax according to the standard histology protocol. About 5-µm sections were prepared, dried, and stained with hematoxylin and eosin (H&E), and two pathologists blindly evaluated the histopathological findings to avoid bias. Scoring of the histopathological findings was designated as 0 for no lesion, 1 for mild, 2 for moderate, and 3 for severe described lesions. The scores were statistically analyzed non-parametrically using Chi-square and Mann–Whitney U-test.

2.6. Immunohistochemical analysis

Paraffin-embedded tissue sections on super-frosted slides were placed in the oven at 60 °C for 20 min to melt the wax and then deparaffinized twice in 100% xylene for 15 min each time. A rehydration step was performed using downgraded ethanol for 5 min each. After rehydration, tissues were washed with distilled water for 5 min before incubating in a microwave oven for antigen recovery in a citrate buffer (pH 6.0). Endogenous peroxidase was quenched for 5 min with 3% H₂O₂. Normal Goat serum blocking serum (cat. no. S‑1000‑20; 5:100 dilution; Vector Laboratories, Inc., CA, USA) was used for blocking of the tissue, followed by incubation with anti‑rabbit polyclonal unconjugated Nrf2 antibodies (cat. no. NBP1‑32822; 1: 500 dilution, Novus biologicals, CO, USA), anti-PPARγ mouse monoclonal antibodies (Catalog #sc-7273; 1:50 dilution; Santa Cruz Biotechnology Inc., Texas, USA), and anti-HO‑1 rabbit polyclonal antibodies (cat. no. ab13243; 1:500 dilution, Abcam, Boston, USA). The primary antibodies (HO-1, Nrf2, PPAR-γ, or NF-κB) were diluted and incubated in sections at 4 °C overnight, followed by 20-min incubation at room temperature with the secondary antibody. After washing sections with PBST, horseradish peroxidase-conjugated secondary antibody was applied for 30 min at room temperature. The peroxidase activity was detected by a chromogen reaction using DAB, and the sections were countered with hematoxylin. After counterstaining with hematoxylin staining for 2–3 s at room temperature, and the sections were dehydrated, cleared in ethanol and xylene, and then mounted on a glass slide. A Leica DM 2500 microscope (Leica Microsystems, Wetzlar, Germany) was used to image the sections at a fixed magnification of x400. From each group, 10 specific areas were captured. ImageJ threshold analysis software version 1.52a (National Institutes of Health, Bethesda, Maryland, USA) was used to measure the relative optical density (ROD%).

2.7. Statistical analysis

Graph pad prism 8 was used for statistical analysis. The results were presented as a mean and standard error of the mean (SEM). The statistical significance between groups for each biomarker was determined by one-way analysis of variance (ANOVA) and the Tukey-post hoc test using GraphPad Prism version 8.1 (GraphPad Prism, San Diego, CA, USA). p < 0.05 was considered to indicate statistical significance.

3. Results

3.1. Effect of lycopene on renal function markers of 5-FU-injected rats

As illustrated in Figure 1(A)–(E), the 5-Fu group had markedly higher serum urea, creatinine, uric acid, and KIM-1 levels and a lower serum albumin level than the control group. In contrast, the lycopene (5 mg) +5-FU and lycopene (10 mg) +5-FU groups had dose-dependent lower serum parameters and higher serum albumin levels than the 5-FU group. Therefore, co-treatment with LYC moderated the renal dysfunction induced by 5-FU. Notably, normal rats that received LYC in a dose of 10 mg lycopene (10 mg) had no changes in serum urea, creatinine, uric, KIM-1, and albumin levels.

Figure 1.

Effect of lycopene on renal function markers of 5-FU-injected rats. Co-treatment with lycopene decreased the levels of serum urea (a), creatinine (B), uric (C), KIM-1 (D), but increased serum albumin (E) induced by 5-FU (30 mg/kg/day; i.p) in a dose-dependent manner, N = 6 rats per group. The results were presented in the form of a mean and SEM. The statistical significance was done using one-way ANOVA and the Tukey-post hoc test. ^a significant versus “control.” ^b significant versus “5-FU,” ^c significant of versus “lycopene (5 mg) +5-FU)” at p < 0.05.

3.2. Effect of lycopene on the histopathological findings of renal tissue of 5-FU-injected rats

Histological examinations notably confirmed the reno-protective effect of LYC. Normal intact glomeruli and tubules are observed in control and lycopene (10 mg)-treated rats. In the 5-FU group, degenerative changes of the glomerular tufts and renal tubules were observed in the form of increased cytoplasmic acidophilia, vacuolar degeneration of glomerular epithelium (mesangial and podocyte), and proximal convoluted tubular epithelium. The distal convoluted tubules appeared dilated with epithelial denudation and desquamation. Some glomeruli appeared hypocellular with epithelial vacuolation and cell death. Moreover, few tubular epithelial cells revealed apoptosis with deep acidophilic cytoplasm and pyknotic nuclei in the kidneys of 5-FU-intoxicated rats. LYC administration with 5-FU (lycopene (5 mg) + 5-FU and lycopene (10 mg) + 5-FU) revealed minimal tubular changes (Figure 2). The renal histopathological changes were scored in different groups and statistical analysis showed that the degenerative changes in glomeruli and proximal convoluted tubules, desquamation, and apoptosis of renal epithelium were significantly higher in 5-FU group than those of lycopene treated groups. The kidneys from rats in the lycopene (10 mg) +5-FU group had histological findings comparable to those of the control group (Table 2).

Figure 2.

Effect of lycopene on the histopathological findings in renal tissues of 5-FU-injected rats. Renal tissues of control and LYC-treated rats (10 mg/kg/day; P.O) had intact glomeruli (star) and tubules (black arrow) with no abnormal changes; however, those of 5-FU-treated rats (30 mg/kg/day; i.p.) showed marked vacuolar degeneration of the glomeruli (black arrowhead), tubular dilatations, epithelial denudation, and desquamation (green arrow) as well as apoptosis (yellow arrow). Rats in the lycopene (5 mg) +5-FU group showed minimal degenerative changes in the glomeruli (black arrow) and apoptosis (yellow arrow). Rats in lycopene (10 mg) +5-FU group restored the renal tissue to control level. H&E, scale bar = 50um.

Table 2.

Scoring of the renal histological lesions in rats and the protective effects of lycopene after 5-FU treatment.

Pathological changes	Control	LYC 10	5-FU	Lycopene (5 mg/kg) +5-FU	Lycopene (10 mg/kg) +5-FU
Degenerative changes of the glomerular tufts and proximal renal tubules	0.0a	0.0a	2.17 ± 0.31b	0.67 ± 0.21c	0.17 ± 0.17a
Denudation and desquamation of distal convoluted tubules	0.0a	0.0a	1.33 ± 0.21b	0.33 ± 0.21c	0.0a
Apoptosis of renal tubular epithelium	0.0a	0.0a	1.17 ± 0.17b	0.50 ± 0.22c	0.17 ± 0.16a
Total	0.0a	0.0a	1.56 ± 0.16	0.5 ± 0.12	0.11 ± 0.07

In one row, values that have the same superscripted letter are not statistically different, and those with different superscripted letters are significantly different.

3.3. Effect of lycopene on 5-FU-induced renal oxidative stress in rats

In 5-FU-treated rats, renal GSH, GPx, GST, and SOD activities were significantly lower, whereas the renal MDA content was significantly higher than those of control rats. Co-treatment of 5-FU with LYC ameliorated in a dose-dependent manner the effects of 5-FU alone on GSH, GST, GPx, SOD activities, and MDA content in renal tissues (Figure 3).

Figure 3.

Effect of lycopene on 5-FU-induced renal oxidative stress in rats. Co-treatment with lycopene (5, 10 mg/kg/day; P.O) ameliorate the decreased GSH, GPx, GST, and SOD levels induced by 5-FU-treated (30 mg/kg/day; i.p.) but decreased MDA content in renal tissues of 5-FU-treated (30 mg/kg/day; i.p.) rats in a dose-dependent manner. N = 6 rats per group. The results were presented in the form of a mean and SEM. The statistical significance was done using one-way ANOVA and the Tukey-post hoc test. ^a significant versus “Normal.” ^b significant versus “5-FU,” ^c significant of “lycopene (10 mg) +5-FU) versus “lycopene (5 mg)+5-FU” at p < 0.05.

3.4. Effect of lycopene on renal PPAR-γ and Nrf2/HO-1 in 5-FU-induced nephrotoxicity in rats

LYC alone increased the levels of PPAR-γ (Figure 4), Nrf2 (Figure 5), and HO-1 (Figure 6) expression. Oral LYC co-treatment ameliorated or attenuated the effect of 5-FU on PPAR-γ, Nrf2, and HO-1 as indicated by the intense brown immunopositivity compared with 5-FU-treated rats. The effect lycopene on PPAR-γ and HO-1 was dose-dependent.

Figure 4.

Effect of lycopene on renal PPAR-γ expression in 5-FU-induced nephrotoxicity in rats. Lycopene partially blocked the effect of 5-FU on PPAR-γ expression in renal tissues of rats. This effect of lycopene on PPAR-γ immunostaining was dose dependent. The intensity of immunostaining was evaluated using ImageJ software. N = 6 rats per group. The results were presented in the form of a mean and SEM. The statistical significance was done using one-way ANOVA and the Tukey-post hoc test. ^a significant versus “Normal”. ^b significant versus “5-FU”, ^c significant versus “lycopene (5 mg) +5-FU” at p < 0.05.

Figure 5.

Effect of lycopene on renal Nrf2 expression in 5-FU-induced nephrotoxicity in rats. Lycopene partially blocked the effect of 5-FU on Nrf2 expression in renal tissues of rats to a similar degree. The intensity of immunostaining was evaluated using ImageJ software. Immunostaining was evaluated using ImageJ software. N = 6 rats per group. The results were presented in the form of a mean and SEM. The statistical significance was done using one-way ANOVA and the Tukey-post hoc test. ^a significant versus “Normal.” ^b significant versus “5-FU,” ^c significant versus “lycopene (5 mg) +5-FU” at p < 0.05.

Figure 6.

Effect of lycopene on renal HO-1 expression in 5-FU-induced nephrotoxicity in rats. Lycopene attenuated in a dose-dependent manner the effect of 5-FU on HO-1 expression in renal tissues of rats. The intensity of immunostaining was evaluated using ImageJ software. N = 6 rats per group. The results were presented in the form of a mean and SEM. The statistical significance was done using one-way ANOVA and the Tukey-post hoc test. ^a significant versus “Normal.” ^b significant versus “5-FU,” ^c significant versus “lycopene (5 mg) +5-FU” at p < 0.05.

3.5. Effect of lycopene on renal inflammatory perturbation in 5-FU-intoxicated rats

LYC alone and control have no significant difference in levels of NF-κB expression. NF-κB was markedly up-regulated after 5-FU injection when compared to the normal control. Compared to the 5-FU treated group, expression of NF-kB was lower in both co-treated groups (lycopene + 5-FU) (Figure 7). TNF-α and IL-6 were significantly higher in the kidneys of the 5-FU group than those of the control (Figure 8(A,B)). These cytokines were significantly lowered in 5-FU rats treated with LYC (both doses) in a dose-dependent manner. In contrast, cytokines IL-10 was lowered significantly in the 5-FU group in comparison with control rats. The effect of 5-FU on IL-10 levels was attenuated in a dose-dependent manner by co-treatment with LYC (Figure 8(C)).

Figure 7.

Effect of lycopene on renal NF-κB expression in 5-FU-induced nephrotoxicity in rats. Both doses of lycopene attenuated the effect of 5-FU on NF-κB expression to a similar degree. The intensity of immunostaining was evaluated using ImageJ software. N = 6 rats per group. The results were presented in the form of a mean and SEM. The statistical significance was done using one-way ANOVA and the Tukey-post hoc test. ^a significant versus “Normal.” ^b significant versus “5-FU,” ^c significant versus “lycopene (5 mg) +5-FU” at p < 0.05.

Figure 8.

Effect of lycopene on renal inflammatory perturbations in 5-FU-intoxicated rats. Lycopene attenuated in a dose-dependent manner the 5-FU-induced elevation of proinflammatory cytokines TNF-α (A) and IL-6 (B) levels and the reduction in the anti-inflammatory cytokine IL-10 level (C). N = 6 rats per group. The results were presented in the form of a mean and SEM. The statistical significance was done using one-way ANOVA and the Tukey-post hoc test. ^a significant versus “Normal.” ^b significant versus “5-FU,” ^c significant versus “lycopene (5 mg) +5-FU” at p < 0.05.

4. Discussion

Cancer is one of the greatest health problems affecting human health and causing a high mortality rate worldwide [42]. Various types of chemotherapeutic agents have been used for the treatment of cancer, while different adverse effects usually accompany their use. Predominantly, nephrotoxicity is one of the major chemotherapy adverse effects [43]. 5-FU is a prodrug that is converted intracellularly into cytotoxic anticancer motilities and usually causes renal injury because it is mainly excreted in the urine [1]. Accordingly, this study aimed to evaluate LYC’s potential renal protective effects against the 5-FU-induced nephrotoxicity. Interestingly, exploration of the possible roles of PPAR-γ, Nrf2/HO-1, and NF-κB in this process.

Kidney function biomarkers were used to evaluate kidney injury [44]. In this study, serum urea, creatinine, uric, and KIM-1 levels were remarkably higher in 5-FU-treated rats. In contrast, the level of albumin lowered significantly, which indicated an acute renal injury due to 5-FU compared to the control group. Indeed, histopathological examination revealed vacuoles in glomerular tufts and tubular epithelium and apoptosis in rats treated with 5-FU [33, 45,46]. In contrast, administration of LYC in a dose-dependent manner attenuated nephrotoxicity. Similar protective effects of LYC were reported against gentamycin- and cisplatin-induced renal injury [32].

Oxidative renal damage is a key part of the pathogenesis of 5-FU-induced nephrotoxicity [47]. In this study, 5-FU significantly lowered the renal levels of GSH and enzymatic activity of GPx, GST, and SOD; meanwhile, the contents of MDA were higher dramatically. In line with this findings, 5-FU impaired oxidant and antioxidant balance in different animal models [48,49]. Co-treatment of 5-FU and LYC restored the content of GSH and enzymatic activity of GPx, GST, and SOD, as well as suppressing the level of MDA, increased cell preservation, and kept the function of the endogenous antioxidant system, indicating that LYC alleviated the renal oxidative stress induced by 5-FU. In line with previous studies, LYC has an antioxidant effect mediated by increasing the level of GSH and enzymatic activity of GPx, GST, and SOD, while reducing the level of MDA, as reported previously in renal injury models [50–52]. Moreover, LYC exerts its antioxidant activity by suppressing the production of reactive oxygen species and potentiating PPARα and Nrf2/HO-1 pathways [53–55] through upregulation of PPARα and Nrf2/HO-1 expression in renal tubules and glomerular cells. The histopathological findings approved that LYC attenuates the nephrotoxic effect of 5-FU by decreasing the degenerative and apoptotic changes of glomerular and tubular epithelium.

Nrf2 is a nuclear transcription factor that regulates the expression of cytoprotective genes encoding antioxidants and detoxifying enzymes such as HO-1 and SOD, as well as the synthesis of GSH. Nrf2 activation protects against drug-induced nephrotoxicity [56,57]. In addition, PPAR-γ has a key role in maintaining the antioxidant status and enzymatic activation that potently protects against chemotherapy-induced nephrotoxicity [58]. Co-activation of PPAR-γ/Nrf2 has been shown to exert cellular protection against oxidative stress in renal and chemotherapy-induced toxicities [59–62]. In this study, PPAR-γ, Nrf2, and HO-1 expression was significantly downregulated in 5-FU-treated rats. In contrast, oral administration of LYC significantly counteracted the adverse effects of 5-FU toxicities on PPAR-γ, Nrf2, and HO-1 downregulation. The antioxidant effects of LYC are crucial in the upregulation of PPAR-γ and Nrf2/HO-1 that modulate the endogenous antioxidant defense system [63,64].

Inflammation significantly affects 5-FU-induced nephrotoxicity [15]. NF-κB/TNF-α/IL-6 pathway has a critical role in regulating inflammatory pathways [7, 65]. Additionally, NF-κB/TNF-α/IL-6 pathway is implicated in different models of renal injury [7]. Notably, IL-10 is anti-inflammatory by inhibiting proinflammatory cytokines and has a kidney protection effect [66]. Compared to the control group, the levels of renal NF-κB and proinflammatory cytokines TNF-α and IL-6 were significantly higher, but the level of IL-10 was significantly lower in 5-FU-treated rats. Similar results were observed on 5-FU-induced mucositis [34, 67]. LYC suppressed several proinflammatory mediators, such as IL-1β and TNF-α, that modulated its anti-inflammatory activity in sulfamethoxazole-induced renal inflammation [68]. Similarly, in the present work, LYC significantly attenuated the 5-FU-induced NF-κB up-regulation and proinflammatory cytokines TNF-α and IL-6 in a dose-dependent manner. Recently, the crosstalk between nuclear Nrf2 and NF-κB systems has been approved that Nrf2 activation leads to upregulation of HO-1, which can interfere with NF-κB nuclear translocation [69]. Based on the results of this study, LYC has a promising effect in attenuating 5-FU-induced renal injury through the modulation of PPAR-γ, Nrf2/HO-1, and NF-κB signals.

Based on the results obtained in the present experimental model, the possible application of lycopene alone or in combination with other nutraceuticals such as phytofluene, phytoene, α-, β-, and γ-carotene, fucoxanthin, astaxanthin, β-cryptoxanthin, zeaxanthin, and lutein [70] could also be provided as a potential future use with therapies of anticancer medications that have adverse effects such as 5-FU, cisplatin, adriamycin (doxorubicin), and/or environmental pollutants induced toxicities such as bisphenol, aflatoxins, and insecticides [71–74].

5. Conclusion

This study revealed that 5-FU induces nephrotoxicity through oxidative stress and inflammatory response. LYC has a beneficial role in maintaining kidney function, and its antioxidative and anti-inflammatory effects are crucial in modulating protein expression of PPAR-γ, Nrf2/ARE, and NF-κB. Therefore, for cancer patients, LYC may be administered alongside 5-FU to reduce its renal side effects.

Funding Statement

This study was supported by Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2024R30), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia. This research was funded by the Researchers Supporting Project number (RSPD2024R811), King Saud University, Riyadh, Saudi Arabia.

Ethics approval

The Institutional Review Board (IRB) approved the experiment ethically, King Abdullah Bin Abdulaziz University Hospital, Riyadh, KSA (HA-01-R-104).

Disclosure statement

The authors declare that they have no conflict of interest.

Data availability statement

The corresponding author can provide the data to support this study’s conclusions upon reasonable request.