The protective role of luteolin against the methotrexate-induced hepato-renal toxicity via its antioxidative, anti-inflammatory, and anti-apoptotic effects in rats

Luteolin attenuates CCl4-induced hepatic injury by inhibiting ferroptosis via SLC7A11

BACKGROUND

Luteolin (3,4,5,7-tetrahydroxy flavone) is reported to strongly protect from acute carbon tetrachloride (CCl4) -induced liver injury or fibrosis. Ferroptosis can be induced by hepatic injury, and contributes to liver fibrosis development. The exact functional mechanism underlying luteolin inhibition of hepatic injury and whether ferroptosis is involved are unclear.

METHODS

Mice model and cell model of liver injury were constructed or induced to explore the effect and molecular mechanisms of Luteolin in the treatment of hepatic injury using CCl4. Cell Counting Kit-8 (CCK-8) and flow cytometry were used to evaluate HepG2 cell viability and apoptosis. The differential expressed genes involved in liver injury were scanned using RNA-seq and confirmed using functional study. Western blot was used to detect the indicators related to ferroptosis.

RESULTS

Luteolin attenuated hepatic injury by alleviating cell morphology and decreasing serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) levels in vivo mice models, and increasing cell viability, downregulating arachidonate 12-lipoxygenase (ALOX12), cyclooxygenase-2 (COX-2) and P21 protein expression, suppressing apoptosis in vitro cell models. Luteolin also inhibited ferroptosis by stimulating glutathione peroxidase 4 (GPX4) and mitochondrial ferritin (FTMT) protein expression, increasing glutathione (GSH) content, and minimizing Fe2+ and malondialdehyde (MDA) levels. Solute carrier family 7a member 11 (SLC7A11) was identified to be a key regulatory gene that participated in luteolin attenuation of CCl4-induced hepatic injuries in HepG2 cells using Microarray assay. Functional study showed that SLC7A11 can alleviate hepatic injury and ferroptosis.

CONCLUSION

Luteolin attenuated CCl4-induced hepatic injury by inhibiting ferroptosis via SLC7A11. SLC7A11 may serve as a novel alternative therapeutic target for hepatic injury.

The potential neuroprotective of luteolin against acetamiprid-induced neurotoxicity in the rat cerebral cortex

Acetamiprid is a class of neuroactive insecticides widely used to control insect pests. The current study aimed to investigate the potential neuroprotective effects of luteolin against acetamiprid-induced neurotoxicity in the rat cerebral cortex. Four equal groups of adult male rats (10 in each): control, acetamiprid (40 mg/kg for 28 days), luteolin (50 mg/kg for 28 days), and acetamiprid+luteolin cotreatment were used. Acetamiprid was shown to alter the oxidative state by increasing oxidant levels [nitric oxide (NO) and malondialdehyde (MDA)] and decreasing antioxidants [glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD), and catalase-(CAT)], with increased activity of nuclear factor erythroid 2-related factor 2-(Nrf2). Likewise, acetamiprid increases the inflammatory response, as evidenced by increased interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and nuclear factor kappa B-(NF-κB). In contrast, the treatment with luteolin brought these markers back to levels close to normal, showing that it protects neurocytes from oxidative damage and the neuroinflammation effects of acetamiprid-induced inflammation. Luteolin also demonstrated a neuroprotective role via the modulation of acetylcholinesterase (AChE) activity in the cerebral cortex tissue. Histopathology showed severe neurodegenerative changes, and apoptotic cells were seen in the acetamiprid-induced cerebral cortex layer, which was evident by increased protein expression levels of Bax and caspase-3 and decreased Bcl-2 levels. Histochemistry confirmed the neuronal degeneration, as proven by the change in neurocyte colour from brown to black when stained with a silver stain. Luteolin may have a neuroprotective effect against biochemical and histopathological changes induced by acetamiprid in the rat cerebral cortex.

Anti-Tumor Effects and Toxicity Reduction Mechanisms of Prunella vulgaris: A Comprehensive Review

PURPOSE

To investigate and systematically describe the mechanism of action of Prunella vulgaris (P. vulgaris) against digestive system tumors and related toxicity reduction.

METHODS

This study briefly describes the history of medicinal food and the pharmacological effects of P. vulgaris, focusing on the review of the anti-digestive tumor effects of the active ingredients of P. vulgaris and the mechanism of its toxicity reduction.

RESULTS

The active ingredients of P. vulgaris may exert anti-tumor effects by inducing the apoptosis of cancer cells, inhibiting angiogenesis, inhibiting the migration and invasion of tumor cells, and inhibiting autophagy. In addition, P. vulgaris active ingredients inhibit the release of inflammatory factors and macrophages and increase the level of indicators of oxidative stress through the modulation of target genes in the pathway to achieve the effect of toxicity reduction.

CONCLUSION

The active ingredients in the medicine food homology plant P. vulgaris not only treat digestive system tumors through different mechanisms but also reduce the toxic effects. P. vulgaris is worthy of being explored more deeply.

Nobiletin alleviates methotrexate-induced hepatorenal toxicity in rats

We investigated the possible ameliorative effects of nobiletin (NBL) against methotrexate (MTX)-induced hepatorenal toxicity in rats. Twenty-eight Wistar albino rats were randomly divided into four groups, namely: Control; MTX (administered 20 mg/kg MTX); MTX+NBL (administered 20 mg/kg MTX and 10 mg/kg NBL per day); and NBL (administered 10 mg/kg/day NBL). Histopathological, immunohistochemical and biochemical analyses were performed on the kidney and liver tissues of rats at the end of the study. MTX caused renal toxicity, as indicated by increases in malondialdehyde (MDA) and caspase-3, as well as decreases in reduced glutathione (GSH), glucose-6-phosphate dehydrogenase (G6PD), glutathione peroxidase (GPx), catalase (CAT) and B-cell lymphoma-2 (Bcl-2). MTX also caused hepatotoxicity, as indicated by increases in 8-hydroxy-2'-deoxyguanosine (8-OHdG), tumor necrosis factor alpha (TNF-α), MDA and caspase-3 and decrease in interleukin 10 (IL-10), GSH, total antioxidant capacity, GPx, G6PD, CAT and Bcl-2. MTX caused histopathological changes in kidney and liver tissues indicating tissue and cellular damage. Administration of NBL concurrently with methotrexate reduced oxidative stress, inflammatory and apoptotic signs, and prevented kidney and liver damage caused by methotrexate. We consider NBL has attenuating and ameliorating effects on methotrexate-induced hepatorenal toxicity.

Pinostrobin, a dietary bioflavonoid exerts antioxidant, anti-inflammatory, and anti-apoptotic protective effects against methotrexate-induced ovarian toxicity in rats

This study investigated the protective activities of pinostrobin (PIN) against methotrexate (MTX)-induced ovarian toxicity. Female rats were administered with PIN (50 mg/kg) for 4 weeks, while MTX was administered from weeks 2-4 of PIN treatment. Serum hormonal profiles, ovarian oxidative stress, inflammatory and apoptotic biomarkers as well as ovarian histomorphometry were evaluated. MTX administration elicited profound deficit in serum progesterone and estrogen (E2) levels, while luteinizing hormone (LH) and follicle stimulating hormone (FSH) were significantly increased. Additionally, MTX administration was associated with significant increases in ovarian malondialdehyde, nitric oxide, NF-кB, TNF-α, IL-6, IL-1β, iNOS and caspase-3 activity, as well as notable reduction in the activities of glutathione peroxidase, catalase and superoxide dismutase as well as the level of glutathione. Whereas, treatment with PIN significantly decreased serum levels of FSH and LH, as well as ovarian levels of NO, MDA, caspase 3, NF-κB, IL-1β, IL-6, TNF-α and iNOS. PIN also significantly upregulated GSH, GPx, CAT and SOD in the ovarian tissues as well as increased serum E2 and progesterone levels compared to the MTX group. Furthermore, PIN significantly restored altered ovarian histoarchitecture in the treated group. These findings suggests that PIN exerts protective effects against MTX-triggered ovarian damages.

Luteolin as a potential hepatoprotective drug: Molecular mechanisms and treatment strategies

Luteolin is a flavonoid widely present in various traditional Chinese medicines. In recent years, luteolin has received more attention due to its impressive liver protective effect, such as metabolic associated fatty liver disease, hepatic fibrosis and hepatoma. This article summarizes the pharmacological effects, pharmacokinetic characteristics, and toxicity of luteolin against liver diseases, and provides prospect. The results indicate that luteolin improves liver lesions through various mechanisms, including inhibiting inflammatory factors, reducing oxidative stress, regulating lipid balance, slowing down excessive aggregation of extracellular matrix, inducing apoptosis and autophagy of liver cancer cells. Pharmacokinetics research manifested that due to metabolic effects, the bioavailability of luteolin is relatively low. It is worth noting that appropriate modification, new delivery systems, and derivatives can enhance its bioavailability. Although many studies have shown that the toxicity of luteolin is minimal, strict toxicity experiments are still needed to evaluate its safety and promote its reasonable development. In addition, this study also discussed the clinical applications related to luteolin, indicating that it is a key component of commonly used liver protective drugs in clinical practice. In view of its excellent pharmacological effects, luteolin is expected to become a potential drug for the treatment of various liver diseases.

In-vivo anticancer efficacy of self-targeted methotrexate-loaded polymeric nanoparticles in solid tumor-bearing rat

Here, cytotoxicity and antitumor efficacy against a chemically (N-methyl-N-nitrosourea) generated mammary tumor in rats were assessed using methotrexate-loaded chitosan nanoparticles (Meth-Cs-NPs). Meth-Cs-NPs intravenous administrated resulted in noticeably decreased tumor incidence, multiplicity, and weight. Further, kidney function tests for the treated groups resulted in noticeably decreased ALP (Meth-Cs-NPs; 244 ± 15, diseases control; 403 ± 14 U/L), Creatinine (Meth-Cs-NPs; 0.81 ± 0.05, diseases control; 2 ± 0.05 mg/dl), and Urea (Meth-Cs-NPs; 56.62 ± 5, diseases control; 113 ± 6 mg/dl) levels, close to a normal control group. Similarly, liver function tests showed significantly decreased serum biomarkers, SGPT (Meth-Cs-NPs; 40 ± 1.8, diseases control; 84 ± 1.9 U/L) and SGOT (Meth-Cs-NPs; 15 ± 2, diseases control; 55 ± 4 U/L) levels in treated groups as compared to the untreated group (diseases control). From the results, pro-inflammatory cytokines were also markedly reduced in the treated group such as, TNF-α (Meth-Cs-NPs; 17.31 ± 1.15, diseases control; 36.9 ± 5 pg/mL), IL-1β (Meth-Cs-NPs; 433.3 ± 66.5, diseases control; 1540 ± 131.1 pg/mL), and IL-6 (Meth-Cs-NPs; 1515 ± 53, diseases control; 2200.6 ± 69 pg/mL) levels. Whereas Meth-Cs-NPs not only helped in lowering tumor multiplicity rates but also decrease inflammation. The studies could be successfully performed in chemically induced mammary tumors due to their easy, quick tumor growth and low mortality rates in rat models. According to the current study, Meth-Cs-NPs have high treatment potency and represent a possible therapeutic alternative for breast cancer treatment.

Protective effects of sitagliptin on methotrexate-induced nephrotoxicity in rats

Methotrexate (MTX), a cytotoxic chemotherapeutic and immunosuppressant agent, is widely used in the treatment of autoimmune diseases and different types of cancers. However, its use has been limited by its life-threatening side effects, including nephrotoxicity and hepatotoxicity. The purpose of this study was to investigate the protective effect of sitagliptin on methotrexate (MTX)-induced nephrotoxicity in rats. Twenty-four rats were divided into four groups: control group, which received the vehicle for 6 days; MTX group, which received a single dose of MTX, followed by five daily doses of vehicle dosing; MTX + sitagliptin group, which received a single dose of MTX 1 h after the first sitagliptin treatment and six daily doses of sitagliptin; and sitagliptin group, which received sitagliptin for 6 days. Both MTX and sitagliptin were given as intraperitoneal injections at a dose of 20 mg/kg body weight. All rats were euthanized on the seventh day of the study. Kidney tissues were harvested and blood samples were collected. Serum levels of blood urea nitrogen (BUN) and creatinine were evaluated. Furthermore, catalase, glutathione peroxidase, superoxide dismutase activities, and malondialdehyde (MDA) levels were determined in kidney tissue. In addition, histopathological analysis was conducted. Histopathological evaluation showed that MTX-induced marked kidney injury. Biochemical analysis revealed a significant increase of BUN and creatinine in the serum of the MTX group. Furthermore, oxidative stress and depressed antioxidant system of the kidney tissues were evident in the MTX group. Sitagliptin did not affect these endpoints when administered alone, but it significantly attenuated the observed MTX-induced effects. These results suggest that sitagliptin exhibits potent anti-oxidant properties against the nephrotoxicity induced by MTX in rats.

Renoprotective Effects of Luteolin: Therapeutic Potential for COVID-19-Associated Acute Kidney Injuries

Acute kidney injury (AKI) has been increasingly reported in critically-ill COVID-19 patients. Moreover, there was significant positive correlation between COVID-19 deaths and renal disorders in hospitalized COVID-19 patients with underlying comorbidities who required renal replacement therapy. It has suggested that death in COVID-19 patients with AKI is 3-fold higher than in COVID-19 patients without AKI. The pathophysiology of COVID-19-associated AKI could be attributed to unspecific mechanisms, as well as COVID-19-specific mechanisms such as direct cellular injury, an imbalanced renin-angiotensin-aldosterone system, pro-inflammatory cytokines elicited by the viral infection and thrombotic events. To date, there is no specific treatment for COVID-19 and its associated AKI. Luteolin is a natural compound with multiple pharmacological activities, including anticoronavirus, as well as renoprotective activities against kidney injury induced by sepsis, renal ischemia and diverse nephrotoxic agents. Therefore, in this review, we mechanistically discuss the anti-SARS-CoV-2 and renoprotective activities of luteolin, which highlight its therapeutic potential in COVID-19-AKI patients.

Pros and cons of NRF2 activation as adjunctive therapy in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease with an important inflammatory component accompanied by deregulated redox-dependent signaling pathways that are feeding back into inflammation. In this context, we bring into focus the transcription factor NRF2, a master redox regulator that exerts exquisite antioxidant and anti-inflammatory effects. The review does not intend to be exhaustive, but to point out arguments sustaining the rationale for applying an NRF2-directed co-treatment in RA as well as its potential limitations. The involvement of NRF2 in RA is emphasized through an analysis of publicly available transcriptomic data on NRF2 target genes and the findings from NRF2-knockout mice. The impact of NRF2 on concurrent pathologic mechanisms in RA is explained by its crosstalk with major redox-sensitive inflammatory and cell death-related pathways, in the context of the increased survival of pathologic cells in RA. The proposed adjunctive therapy targeted to NRF2 is further sustained by the existence of promising NRF2 activators that are in various stages of drug development. The interference of NRF2 with conventional anti-rheumatic therapies is discussed, including the cytoprotective effects of NRF2 for alleviating drug toxicity. From another perspective, the review presents how NRF2 activation would be decreasing the efficacy of synthetic anti-rheumatic drugs by increasing drug efflux. Future perspectives regarding pharmacologic NRF2 activation in RA are finally proposed.

Protective effect of luteolin against chemical and natural toxicants by targeting NF-κB pathway

Humans are continuously exposed to environmental, occupational, consumer and household products, food, and pharmaceutical substances. Luteolin, a flavone from the flavonoids family of compounds, is found in different fruits and vegetables. LUT is a strong anti-inflammatory (via inhibition of NF-κB, ERK1/2, MAPK, JNK, IL-6, IL-8, and TNF-α) and antioxidant agent (reducing ROS and enhancement of endogenous antioxidants). LUT can chelate transition metal ions responsible for ROS generation and consequently repress lipoxygenase. It has been proven that NF-κB, as a commom cellular pathway plays a considerable role in the progression of inflammatory process and stimulates the expression of genes encoding inducible pro-inflammatory enzymes (iNOS and COX-2) and cytokines including IL-1β, IL-6, and TNF-α. This review summarizes the available literature discussing LUT and its potential protective role against pharmaceuticals-, metals-, and environmental compounds-induced toxicities. Furthermore, the review explains the involved protective mechanisms, especially inhibition of the NF-κB pathway.

Effect of gervital in attenuating hepatotoxicity caused by methotrexate or azathioprine in adult albino rats

Methotrexate (MTX) and azathioprine (AZA) are chemotherapeutic, antimetabolic, and immunosuppressive agents with substantial risks such as oxidative lesions to the liver. This study examined the effect of grape seed extract (GSE; gervital) in attenuating hepatotoxicity caused by MTX or AZA treatment. Rats were divided into six groups (six rats per group): Group I, normal control group; Group II, GSE (150 mg/kg/day); Group III, MTX (8 mg/kg/week); Group IV, AZA (15 mg/kg/day); Group V, GSE (150 mg/kg/day) + MTX (8 mg/kg/week); and Group VI, GSE (150 mg/kg/day) + AZA (15 mg/kg/day). After 35-day experimental period, all rats were sacrificed and blood was collected for biochemical study and hemoglobin (Hb) assessment. The liver was weighed and triaged for histological, ultrastructural, and biochemical studies. MTX and AZA treatment decreased Hb levels, increased relative liver weight, increased the activity of glutamate pyruvate transaminase (ALT) and glutamate oxaloacetate transaminase (AST) aminotransferase (ALT) and aspartate aminotransferase (AST) values, and displayed histopathological and ultrastructural alterations. These changes included the disorganization of hepatocytes, pyknosis, karyolysis of some nuclei, and mononuclear leukocytic infiltration. The liver with significant oxidative stress (OS) showed decreased reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) and increased malondialdehyde (MDA) levels. In contrast, GSE administration ameliorated ALT, AST, and all histopathological and ultrastructural changes. GSE treatment also reduced MDA levels but increased the antioxidant parameters. In conclusion, it was concluded that GSE supplementation could be considered as a promising antioxidant in reducing OS, histopathological and ultrastructural alterations induced by MTX and AZA.

Protective Effect of Pycnogenol against Methotrexate-Induced Hepatic, Renal, and Cardiac Toxicity: An In Vivo Study

Methotrexate (MTX) is one of the most commonly used chemotherapies for various types of cancer, including leukemia, breast cancer, hepatocarcinoma, and gastric cancers. However, the efficacy of MTX is frequently limited by serious side effects. Several studies have reported that the cytotoxic effect of MTX is not limited to cancer cells but can also affect normal tissues, leading to prospective damage to many organs. In the present study, we extensively investigated the molecular and microscopic basis of MTX-induced toxicity in different organs (liver, kidney, and heart) and explored the possible protective effect of pycnogenol, a polyphenolic component extracted from the bark of P. pinaster, to attenuate these effects. Biochemical analysis revealed that administration of MTX significantly reduced the function of the liver, kidney, and heart. Histological and immunohistochemical analysis indicated that MTX treatment caused damage to tissues of different organs. Interestingly, administration of pycnogenol (10, 20, and 30 mg/kg) significantly attenuated the deterioration effects of MTX on different organs in a dose-dependent manner, as demonstrated by biochemical and histological analysis. Our results reveal that pycnogenol successfully ameliorated oxidative damage and reduced toxicity, inflammatory response, and histological markers induced by methotrexate treatment. Taken together, this study provides solid evidence for the pharmacological application of pycnogenol to attenuate damage to different organs induced by MTX treatment.