Modulation of methotrexate-induced intestinal mucosal injury by dietary factors

The Impact of Gut Microbiota Changes on Methotrexate-Induced Neurotoxicity in Developing Young Rats

Methotrexate (MTX) is an essential part of therapy in the treatment of acute lymphoblastic leukemia (ALL) in children, and inferior intellectual outcomes have been reported in children who are leukemia survivors. Although several studies have demonstrated that the interaction between gut microbiota changes and the brain plays a vital role in the pathogenesis of chemotherapy-induced brain injury, preexisting studies on the effect of MTX on gut microbiota changes focused on gastrointestinal toxicity only. Based on our previous studies, which revealed that MTX treatment resulted in inferior neurocognitive function in developing young rats, we built a young rat model mimicking MTX treatment in a child ALL protocol, trying to investigate the interactions between the gut and brain in response to MTX treatment. We found an association between gut microbiota changes and neurogenesis/repair processes in response to MTX treatment, which suggest that MTX treatment results in gut dysbiosis, which is considered to be related to MTX neurotoxicity through an alteration in gut-brain axis communication.

Dietary restriction rescues 5-fluorouracil-induced lethal intestinal toxicity in old mice by blocking translocation of opportunistic pathogens

Chemotherapy remains a major treatment for malignant tumors, yet the application of standard dose intensity chemotherapy is limited due to the side effects of cytotoxic drugs, especially in old populations. The underlying mechanisms of cytotoxicity and strategies to increase the safety and tolerance of chemotherapy remain to be explored. Using 5-fluorouracil (5-FU), a cornerstone chemotherapeutic drug, we demonstrate that the main cause of death in ad libitum (AL) fed mice after 5-FU chemotherapy was infection caused by translocation of intestinal opportunistic pathogens. We show that these opportunistic pathogens greatly increase in the intestine after chemotherapy, which was closely related to loss of intestinal lysozyme. Of note, two weeks of dietary restriction (DR) prior to chemotherapy significantly protected the loss of lysozyme and increased the content of the beneficial Lactobacillus genera, resulting in a substantial inhibition of intestinal opportunistic pathogens and their translocation. The rescue effect of DR could be mimicked by Lysozyme or Lactobacillus gavage. Our study provides the first evidence that DR achieved a comprehensive protection of the intestinal physical, biological and chemical barriers, which significantly improved the overall survival of 5-FU-treated mice. Importantly, the above findings were more prominent in old mice. Furthermore, we show that patients over 65 years old have enriched opportunistic pathogens in their gut microbiota, especially after 5-FU based chemotherapy. Our study reveals important mechanisms for the poor chemotherapy tolerance of the elderly population, which can be significantly improved by short-term DR. This study generates new insights into methods for improving the chemotherapeutic prognosis by increasing the chemotherapy tolerance and safety of patients with malignant tumors.

Zinc and L-carnitine combination with or without methotrexate prevents intestinal toxicity during arthritis treatment via Nrf2/Sirt1/Foxo3 pathways: an In vivo and molecular docking approach

Methotrexate (MTX) is an antifolate that is inescapable and widely used to treat autoimmune diseases and is the gold standard medicine for the arthritic condition. Despite its importance, it is more prone to gastrointestinal toxicity, which is most common in arthritis patients during MTX treatment. Combination therapies are required to ensure MTX's antiarthritic activity while providing gastrointestinal protection. Zinc (Zn) and L-carnitine (Lc) are well-known potent antioxidants and anti-inflammatory supplements with promising results in pre-clinical studies. Arthritis was induced in Wistar rat's ankles with Freund's adjuvant and treated with either MTX (2.5 mg/kg b.w per week for two weeks) or Zn (18 mg/kg b.w. per day) Lc (200 mg/kg b.w. per day) individually or in combination (MTX + Zn Lc). The antiarthritic effects were evaluated by body weight, paw volume, ankle tissue, and joint histopathology. At the same time, anti-toxicity/gastrointestinal protective activity was examined by tissue oxidative stress markers, antioxidants, mitochondrial function, inflammatory mediators, and antioxidant signaling proteins and their binding mechanism. Repercussions of MTX intoxication induced upregulation of oxidative stress markers, antioxidant depletion, ATP depletion, decreased expression of Nrf2/Sirt1/Foxo3, and the overexpression of inflammatory mediators attenuated by co-treatment with Zn Lc. Zn Lc markedly mitigated MTX-instigated intestinal injury by activating antioxidant signaling mechanisms Nrf2/Sirt1/Foxo3 signaling and tissue architectural anomalies and exhibited an enhanced antiarthritic effect. In conclusion, we report that Zn Lc and MTX combination could presumably protect the intestine from low-dose MTX which managed arthritis but induced severe intestinal damage with increased inflammation and downregulated Nrf2/Sirt1/Foxo3 pathway.

L-carnitine and Zinc supplementation impedes intestinal damage in methotrexate-treated adjuvant-induced arthritis rats: Reinstating enterocyte proliferation and trace elements

BACKGROUND

Methotrexate (MTX), a folic acid analogue, is used as a first-line treatment for rheumatoid arthritis (RA) since it has more therapeutic mechanisms than any other drug. Being an undeniable drug for the treatment of arthritis, even low-dose MTX provokes intestinal toxicity as a primary adverse effect and does not revive an anti-inflammatory element. Thus, our study aims to elucidate the anti-arthritic and prophylactic activity of supplements L-carnitine (L) and zinc (Z) against MTX-mediated intestinal damage in arthritis rats.

METHODS

The rats were assessed for arthritic parameters such as body weight, paw volume, x-ray scan, and serum trace elements level. To analyze the toxic effects of MTX in the rats, intestine pH, mucosal weight, digestive enzymes, myeloperoxidase, histopathological, and immunohistochemical analysis were performed.

RESULTS

Our study demonstrated that the arthritic parameters have shown that MTX has an ameliorative effect on arthritic rats. Besides, our findings showed that low-dose MTX (2.5 mg/kg b.w.) given once a week for two weeks during arthritis treatment had toxic effects in the rat's intestine, as evidenced by changes in intestine pH and mucosal weight, decreased digestive enzymes, increased MPO, and degenerative changes in histopathological analysis. Concurrent therapy of LZ with MTX, on the other hand, restored the modifications in these parameters.

CONCLUSION

MTX in combination with LZ effectively manages arthritis than monotherapy and significantly prevents MTX-induced intestinal damage in arthritis rats. Thus, LZ could be used as an improved therapeutic and safety for MTX-instigated intestinal damage during arthritis treatments. Therefore, our combination of L-carnitine and zinc with MTX would be promising prophylactic activity for arthritis patients.

Albiflorin ameliorates inflammation and oxidative stress by regulating the NF-κB/NLRP3 pathway in Methotrexate-induced enteritis

Methotrexate (MTX) treats various diseases but also damages intestinal barrier and leads to enteritis. Albiflorin (ALB) has a variety of pharmacological effects, including antioxidant, anti-inflammation and anti-apoptosis. In the present study, we evaluated the therapeutic effect of ALB on MTX-induced enteritis and investigated the possible mechanisms involved. Male SD rats were intraperitoneally injected with 7 mg/kg MTX for three consecutive days to establish the enteritis model. ALB (20 or 40 mg/kg/day) was intragastrically administrated since two days prior MTX treatment and lasted for six days. We found that ALB treatment increased body weight and intestinal weight of rats with MTX injection. The disease activity index (DAI) score was also decreased after ALB administration. In histological examination, ALB treatment attenuated inflammatory cells infiltration and promoted survival of goblet cells. In detection of inflammatory-associated factors, ALB treatment decreased CD68⁺ cells infiltration, inhibited myeloperoxidase activity, and suppressed intercellular cell adhesion molecule-1 and cyclooxygenase-2 expression. Additionally, ALB reduced malondialdehyde, glutathione levels, inhibited superoxide dismutase activity and suppressed reactive oxygen species production. Moreover, ALB treatment effectively inhibited NLRP3, as well as caspase 1 p20 and interleukin (IL)-1β and 18 expression. Finally, nuclear factor-κB (NF-κB) p65 phosphorylation and nuclear translocation were also demonstrated to be blocked upon ALB treatment. In conclusion, our findings indicated that ALB alleviated MTX-induced enteritis via inhibiting the NF-κB/NLRP3 pathway.

Decreased Tissue Omega-6/Omega-3 Fatty Acid Ratio Prevents Chemotherapy-Induced Gastrointestinal Toxicity Associated with Alterations of Gut Microbiome

Gastrointestinal toxicity (GIT) is a debilitating side effect of Irinotecan (CPT-11) and limits its clinical utility. Gut dysbiosis has been shown to mediate this side effect of CPT-11 by increasing gut bacterial β-glucuronidase (GUSB) activity and impairing the intestinal mucosal barrier (IMB). We have recently shown the opposing effects of omega-6 (n-6) and omega-3 (n-3) polyunsaturated fatty acids (PUFA) on the gut microbiome. We hypothesized that elevated levels of tissue n-3 PUFA with a decreased n-6/n-3 PUFA ratio would reduce CPT-11-induced GIT and associated changes in the gut microbiome. Using a unique transgenic mouse (FAT-1) model combined with dietary supplementation experiments, we demonstrate that an elevated tissue n-3 PUFA status with a decreased n-6/n-3 PUFA ratio significantly reduces CPT-11-induced weight loss, bloody diarrhea, gut pathological changes, and mortality. Gut microbiome analysis by 16S rRNA gene sequencing and QIIME2 revealed that improvements in GIT were associated with the reduction in the CPT-11-induced increase in both GUSB-producing bacteria (e.g., Enterobacteriaceae) and GUSB enzyme activity, decrease in IMB-maintaining bacteria (e.g., Bifidobacterium), IMB dysfunction and systemic endotoxemia. These results uncover a host-microbiome interaction approach to the management of drug-induced gut toxicity. The prevention of CPT-11-induced gut microbiome changes by decreasing the tissue n-6/n-3 PUFA ratio could be a novel strategy to prevent chemotherapy-induced GIT.

Pharmacomicrobiology of Methotrexate in Rheumatoid Arthritis: Gut Microbiome as Predictor of Therapeutic Response

Rheumatoid arthritis (RA) is a disabling autoimmune disease with invasive arthritis as the main manifestation and synovitis as the basic pathological change, which can cause progressive destruction of articular cartilage and bone, ultimately leading to joint deformity and loss of function. Since its introduction in the 1980s and its widespread use in the treatment of RA, low-dose methotrexate (MTX) therapy has dramatically changed the course and outcome of RA treatment. The clinical use of this drug will be more rational with a better understanding of the pharmacology, anti-inflammatory mechanisms of action and adverse reaction about it. At present, the current clinical status of newly diagnosed RA is that MTX is initiated first regardless of the patients’ suitability. But up to 50% of patients could not reach adequate clinical efficacy or have severe adverse events. Prior to drug initiation, a prognostic tool for treatment response is lacking, which is thought to be the most important cause of the situation. A growing body of studies have shown that differences in microbial metagenomes (including bacterial strains, genes, enzymes, proteins and/or metabolites) in the gastrointestinal tract of RA patients may at least partially determine their bioavailability and/or subsequent response to MTX. Based on this, some researchers established a random forest model to predict whether different RA patients (with different gut microbiome) would respond to MTX. Of course, MTX, in turn, alters the gut microbiome in a dose-dependent manner. The interaction between drugs and microorganisms is called pharmacomicrobiology. Then, the concept of precision medicine has been raised. In this view, we summarize the characteristics and anti-inflammatory mechanisms of MTX and highlight the interaction between gut microbiome and MTX aiming to find the optimal treatment for patients according to individual differences and discuss the application and prospect of precision medicine.

Berberine and/or zinc protect against methotrexate-induced intestinal damage: Role of GSK-3β/NRF2 and JAK1/STAT-3 signaling pathways

AIM

The present study was undertaken to elucidate the potential protective mechanism of berberine (BBR) and/or zinc (Zn) against methotrexate (MTX)-induced intestinal injury.

METHODS

Five groups of rats were assigned; normal group (received vehicle), MTX group (20 mg/kg; i.p. single dose), and the other three groups received a single daily oral dose of BBR (50 mg/kg), Zn (5 mg/kg), and BBR plus Zn respectively, for 5 days before MTX and 5 days after.

RESULTS

Our results emphasized the toxic effect of MTX on rat's intestine as shown by disturbance of oxidant/antioxidant status, down-regulation of NRF2, SIRT1, FOXO-3, Akt, and mTOR expressions, along with up-regulation of GSK-3β, JAK1, and STAT-3 expressions. Besides, severe intestinal histopathological changes were also observed. On the contrary, BBR and/or Zn produced marked protection against MTX-induced intestinal toxicity via amelioration of oxidative stress, improving NRF2, SIRT1, FOXO-3, GSK-3β, Akt, mTOR, JAK1, and STAT-3 alterations. Moreover, our treatments significantly restored histopathological abnormalities. Interestingly, combination therapy of BBR plus Zn exhibited higher effectiveness than mono-therapy.

SIGNIFICANCE

BBR plus Zn could be used as a novel therapy for the treatment of MTX-induced intestinal damage through modulation of GSK-3β/NRF2, Akt/mTOR, JAK1/STAT-3, and SIRT1/FOXO-3 signaling pathways.