Epigallocatechin Gallate Attenuates Gentamicin-Induced Nephrotoxicity by Suppressing Apoptosis and Ferroptosis

Sodium Selenite Prevents Matrine-Induced Nephrotoxicity by Suppressing Ferroptosis via the GSH-GPX4 Antioxidant System

Matrine (MT), an active ingredient derived from Sophor flavescens Ait, is used as a therapeutic agent to treat liver disease and cancer. However, the serious toxic effects of MT, including nephrotoxicity, have limited its clinical application. Here, we explored the involvement of ferroptosis in MT-induced kidney injury and evaluated the potential efficacy and underlying mechanism of sodium selenite (SS) in attenuating MT-induced nephrotoxicity. We found that MT not only disrupts renal structure in mice but also induces the death of NRK-52E cells. Additionally, MT treatment resulted in significant elevations in ferrous iron, reactive oxygen species (ROS) and lipid peroxidation levels, accompanied by decreases in glutathione (GSH) and glutathione peroxidase (GPx) levels. SS effectively mitigated the alterations in ferroptosis-related indicators caused by MT and prevented MT-induced nephrotoxicity as effectively as Fer-1 in vivo and in vitro. SS also reversed the MT-induced reduction in GPX4, CTH and xCT protein levels. However, the glutathione peroxidase 4 (GPX4) inhibitor RSL3 and knockdown of GPX4, CTH, or xCT via siRNA abolished the protective effect of SS against MT-induced nephrotoxicity, indicating that SS exhibited antiferroptotic effects via the GSH-GPX4 antioxidant system. Overall, MT-induced ferroptosis triggers nephrotoxicity, and SS is a promising therapeutic drug for alleviating MT-induced renal injury by activating the GSH-GPX4 axis.

The anti-inflammatory properties of green tea extract protect against gentamicin-induced kidney injury

We assessed in vivo the protective effects and underlying antioxidant and anti-inflammatory properties of dry green tee extract (GTE) on glomerular and tubular kidney function and structure in an experimental model of gentamicin (GEN)-induced nephrotoxicity. Wistar rats were divided into four groups and treated daily for 10 days. The control group received distilled water; the GTE group received 20 μg/g body weight (BW) GTE by gavage; the GEN group received 100 mg/g BW GEN intraperitoneally; and the GEN+GTE group received GTE and GEN simultaneously, as described above. At the beginning and end of treatment, the serum creatinine, fractional excretion of sodium and potassium, and plasma heme oxygenase (HO)-1 levels and oxidative stress (OS) were assessed. At the end of the experiment, kidney fragments were collected for histological evaluation and immunohistochemical studies of cyclooxygenase (COX)-2 and nuclear factor (NF)kB. The levels of interleukin (IL)-1b, IL-4, IL-6, IL-10 and monocyte chemotactic protein (MCP)-1 were measured in kidney tissue. The results showed that GTE attenuated significantly kidney structural injury and prevented GEN-induced kidney functional injury (glomerular and tubular function). GTE significantly attenuated the kidney tissue increase of the proinflammatory mediators NF-kB, COX2, IL-1b and MCP-1 and significantly increased the kidney expression of the anti-inflammatory cytokines IL-6 and IL-10. However, GTE did not prevent OS increase in GEN-treated animals. In conclusion, GTE protected against GEN nephrotoxicity, likely due to direct blockade of the inflammatory cascade, which might had occurred independently of its antioxidant effect.

Lactoferrin alleviates gentamicin-induced acute kidney injury in rats by suppressing ferroptosis: Highlight on ACSL4, SLC7A11, NCOA4, FSP1 pathways and miR-378a-3p, LINC00618 expression

The use of gentamicin (GNT) is associated with acute kidney injury (AKI). Ferroptosis is a newly recognized iron-dependent, non-apoptotic cell death that can lead to AKI. Lactoferrin (LF), an iron-binding glycoprotein, was previously reported to be renoprotective. Nonetheless, LF's impact on GNT-induced AKI and ferroptosis has not yet been investigated. Accordingly, we assessed the dose-dependent effect of LF on GNT-induced AKI and its influence on ferroptosis. Thirty-six male rats were allocated as control, LF, GNT (100 mg/kg/day, i.p.), and groups given LF (100, 200, and 300 mg/kg, p.o.) for 14 days prior concurrently with GNT (Day 8-14). The high dose of LF (300 mg/kg) showed better histopathological picture, higher creatinine clearance, reduced serum and urine levels of kidney injury markers when compared to the GNT group and the lower two doses. These nephroprotective effects of LF can be attributed to the observed reduction in renal ferrous iron, 4-HNE, and MDA, miR-378a-3p and ALOX15 expression, TFR1, NCOA4, and ACSL4 protein expression and the increased LINC00618 expression, GSH levels, GPX4, SLC7A11, and FSP1 protein expression. In conclusion, LF high dose was the most renoprotective against GNT-induced AKI, in which suppression of ferroptosis pathways was a likely contributor to its protective mechanism.

Ferroptosis as a molecular target of epigallocatechin gallate in diseases

CONTEXT

Ferroptosis is a novel form of cell death characterised by iron overload and lipid peroxidation. It is closely associated with many diseases, including cardiovascular diseases, tumours, and neurological diseases. The use of natural chemicals to modulate ferroptosis is of great concern because of the critical role ferroptosis plays in disease. The main active ingredient in green tea is epigallocatechin gallate (EGCG), which is the most abundant catechin in green tea. EGCG shows a wide range of biological and therapeutic effects in various diseases, including anti-inflammatory, antioxidant, anticancer, and cardioprotective.

OBJECTIVE

The purpose of this article is to summarise the existing information on the relationship between EGCG and ferroptosis.

METHODS

Articles related to EGCG and ferroptosis were searched in PubMed and Web of Science databases, and the literature was analysed.

RESULTS AND CONCLUSION

EGCG could improve ferroptosis-related diseases and affect the development of ferroptosis by regulating the nuclear factor erythroid 2-related factor 2, autophagy, microRNA, signal transducer and activator of transcription 1, and protein kinase D1 signalling pathways.

Nrf2/FSP1/CoQ10 axis-mediated ferroptosis is involved in sodium aescinate-induced nephrotoxicity

Sodium aescinate (SA), an active compound found in horse chestnut seeds, is widely used in clinical practice. Recently, the incidence of SA-induced adverse events, particularly renal impairment, has increased. Our previous work demonstrated that SA causes severe nephrotoxicity via nephrocyte ferroptosis; however, the underlying mechanism remains to be fully elucidated. In the current study, we investigated additional molecular pathways involved in SA-induced nephrotoxicity. Our results showed that SA inhibited cell viability, disrupted cellular membrane integrity, and enhanced reactive oxygen species (ROS), ferrous iron (Fe2+), and malondialdehyde (MDA) levels, as well as lipid peroxidation in rat proximal renal tubular epithelial cell line (NRK-52E) cells. SA also depleted coenzyme Q10 (CoQ10, ubiquinone) and nicotinamide adenine dinucleotide (NADH) and reduced ferroptosis suppressor protein 1 (FSP1) and polyprenyltransferase (coenzyme Q2, COQ2) activity, triggering lipid peroxidation and ROS accumulation in mouse kidneys and NRK-52E cells. The overexpression of COQ2, FSP1, or CoQ10 (ubiquinone) supplementation effectively attenuated SA-induced ferroptosis, whereas iFSP1 or 4-formylbenzoic acid (4-CBA) pretreatment exacerbated SA-induced nephrotoxicity. Additionally, SA decreased nuclear factor-erythroid-2-related factor 2 (Nrf2) levels and inhibited Nrf2 binding to the -1170/-1180 bp ARE site in FSP1 promoter, resulting in FSP1 suppression. Overexpression of Nrf2 or its agonist dimethyl fumarate (DMF) promoted FSP1 expression, thereby improving cellular antioxidant capacity and alleviating SA-induced ferroptosis. These results suggest that SA-triggers renal injury through oxidative stress and ferroptosis, driven by the suppression of the Nrf2/FSP1/CoQ10 axis.

Potential protective effects of Acacia nilotica (L.) against gentamicin - induced nephrotoxicity by suppressing renal redox imbalance, inflammatory stress and caspase-dependent apoptosis in Wistar rats

Gentamicin-induced nephrotoxicity limits its therapeutic use as an effective aminoglycoside. Herbal drugs have a distinct place in the world of pharmaceuticals since they are safe, effective, and cost-efficient. Acacia nilotica (L.) has long been recognized for its antihypertensive, antioxidant, anti-inflammatory, and antiplatelet aggregatory benefits in traditional medicine. Still, the protective effect of Acacia nilotica on gentamicin-induced nephrotoxicity is still unknown. Thus, the goal of this research was to examine the protection of ethanolic extract of Acacia nilotica (ANE) against nephrotoxicity triggered by Gentamicin.

Thirty-six rats were randomly divided into six groups containing six rats in each group. The distilled water were given in control group. The rats in groups two and three were administered metformin and gentamicin respectively. In groups five and six, rats were administered ANE at doses of 100 and 200 mg/kg. Ten days of daily treatments were given. The urea, creatinine, uric acid, and LDH levels were analyzed on serum, whereas histological evaluation, MDA, GSH, SOD, CAT, TNF-α, IL-6, and caspase-3, were performed on kidney tissue on day 11. The gentamicin-treated group exhibited a significantly elevated MDA, and lower levels of antioxidant enzymes. Kidney function markers, inflammatory markers and caspase-3 expression were significantly elevated in the gentamicin-treated group. ANE significantly restored kidney function biomarkers, upregulated biochemical levels, inhibited TNF-α, caspase-3, cytokine expression, and reduced histological lesions.

In conclusion, ANE has the ability to prevent gentamicin-induced nephrotoxicity and reduce nephrotoxic damage. As such, it may represent an effective therapy for patients receiving gentamicin treatment.

Monoterpene linalool restrains gentamicin-mediated acute kidney injury in rats by subsiding oxidative stress, apoptosis, and the NF-κB/iNOS/TNF-α/IL-1β pathway and regulating TGF-β

The clinical use of gentamicin (GM) is restricted by its nephrotoxic effects. This study aimed for the first time to elucidate the ameliorative effects of the monoterpene linalool (Lin) against GM-mediated acute kidney injury in rats. A total of thirty-two rats were subdivided into four equal groups: control (saline), Lin (100 mg/kg/day), GM (100 mg/kg/day), and GM + Lin (100 and 100 mg/kg/day). Lin and GM were intraperitoneally administered for 12 days. Our results illustrated that Lin ameliorated GM-mediated renal histopathological abnormalities and reduced serum urea and creatinine levels in rats exposed to GM. Lin treatment mitigated oxidative stress in nephrotoxic animals as manifested by reducing serum and renal levels of malondialdehyde and increasing the activities of serum and renal glutathione peroxidase and renal catalase. Moreover, Lin markedly inhibited GM-triggered inflammation by downregulating NF-κB, iNOS, TNF-α, and IL-1β and reducing renal myeloperoxidase activity and nitric oxide levels. Interestingly, Lin repressed GM-induced apoptosis, as reflected by a marked downregulation of Bax and caspase-3 expression, concurrent with the upregulation of Bcl2 expression. Finally, Lin administration led to a significant downregulation of TGF-β expression in nephrotoxic animals. In summary, Lin ameliorated GM-mediated nephrotoxicity in rats, at least through its antioxidant, anti-inflammatory, and anti-apoptotic activities and by modulating TGF-β.

The role of ferroptosis in acute kidney injury: mechanisms and potential therapeutic targets

Acute kidney injury (AKI) is one of the most common and severe clinical renal syndromes with high morbidity and mortality. Ferroptosis is a form of programmed cell death (PCD), is characterized by iron overload, reactive oxygen species accumulation, and lipid peroxidation. As ferroptosis has been increasingly studied in recent years, it is closely associated with the pathophysiological process of AKI and provides a target for the treatment of AKI. This review offers a comprehensive overview of the regulatory mechanisms of ferroptosis, summarizes its role in various AKI models, and explores its interaction with other forms of cell death, it also presents research on ferroptosis in AKI progression to other diseases. Additionally, the review highlights methods for detecting and assessing AKI through the lens of ferroptosis and describes potential inhibitors of ferroptosis for AKI treatment. Finally, the review presents a perspective on the future of clinical AKI treatment, aiming to stimulate further research on ferroptosis in AKI.

The Antioxidant, Antibacterial and Cell-Protective Properties of Bioactive Compounds Extracted from Rowanberry (Sorbus aucuparia L.) Fruits In Vitro

Considering that Sorbus aucuparia fruits have been underutilized despite their tremendous potential, this study aimed to correlate the in vitro antioxidant, antibacterial and cell-protective abilities of fruit extracts derived from Sorbus aucuparia Romanian cultivars with their phytochemical composition. Therefore, following the preparation of ethanolic and carotenoid extracts, phytochemical screening was performed using UV-Vis and HPLC-DAD-ESI-MS methods. The antioxidant activity was analyzed using DPPH and FRAP tests. As the results revealed high contents of bioactive compounds (polyphenols 1.11 mg GAE/g DM, flavonoids 430.06 µg QE/g DM and carotenoids 95.68 µg/g DM) and an important antiradical action (DPPH 24.51 mg/mL and FRAP 0.016 µM TE/mL), we chose to further examine the fruits' biological properties. The antibacterial capacity was assessed employing agar well diffusion and broth microdilution techniques, with fruits displaying an intense activity against MSSA, MRSA and Enterococcus faecalis, but also E. coli and Pseudomonas aeruginosa. The cell-protective activity was analyzed on gentamicin-stressed renal cells, through MTT and Annexin V-FITC assays. Importantly, a significant increase in viability was registered on stressed cells following extract administration in low doses; nevertheless, viability was noticed to decline when exposed to elevated concentrations, potentially due to the cumulative actions of the extract and gentamicin. These findings offer novel light on the antibacterial activity of Sorbus aucuparia Romanian cultivars, as well as their cell-protective ability in renal cell injury.

Potential mechanism of tea for treating osteoporosis, osteoarthritis, and rheumatoid arthritis

Osteoporosis (OP), osteoarthritis (OA), and rheumatoid arthritis (RA) are common bone and joint diseases with a high incidence and long duration. Thus, these conditions can affect the lives of middle-aged and elderly people. Tea drinking is a traditional lifestyle in China, and the long-term intake of tea and its active ingredients is beneficial to human health. However, the mechanisms of action of tea and its active ingredients against OP, OA, and RA are not completely elucidated. This study aimed to assess the therapeutic role and related mechanisms of tea and its active ingredients in OP, OA, and RA. Moreover, it expanded the potential mechanisms of tea efficacy based on network pharmacology and molecular docking. Results showed that tea has potential anti-COX properties and hormone-like effects. Compared with a single component, different tea components synergize or antagonize each other, thereby resulting in a more evident dual effect. In conclusion, tea has great potential in the medical and healthcare fields. Nevertheless, further research on the composition, proportion, and synergistic mechanism of several tea components should be performed.

EGCG attenuated acute myocardial infarction by inhibiting ferroptosis via miR-450b-5p/ACSL4 axis

BACKGROUND

Epigallocatechin gallate (EGCG) has multiple biological effects such as anti-tumor multiple drug resistance, antioxidation and anti-inflammatory properties. Ferroptosis is the main driving factor of ischemic heart injury, thus inhibiting ferroptosis may prove to be an effective treatment strategy for cardiovascular diseases. However, the role of EGCG on ferroptosis in ischemic myocardium and underlying mechanisms remain uncertain.

PURPOSE

This study was aimed to investigate the effects and potential mechanisms of EGCG on myocardial ischemic-induced ferroptosis both in vitro and in vivo.

METHODS

Cardiomyocyte hypoxia model and mouse acute myocardial infarction (AMI) model were established in vitro and in vivo. MiR-450b-5p and ACSL4 silencing or overexpression plasmids were transfected, with or without EGCG pretreatment. Cell viability was determined by the CCK-8 assay. Hematoxylin and eosin (HE) staining and transmission electron microscopy (TEM) were used to evaluate the morphologic alterations. TTC staining was used to observe the infarction area, and echocardiography was adopted to appraise the heart function. Using flow cytometry, the presence of reactive oxygen species (ROS) was assessed. The content of cardiac troponin I (cTn I), glutathione (GSH), malondialdehyde (MDA), divalent iron ions (Fe2+) and superoxide dismutase (SOD) were detected using reagent kits. A luciferase activity assay was performed to assess the binding ability of miR-450b-5p to ACSL4. Expressions of related genes and proteins were measured by RT-qPCR and western blotting respectively.

RESULTS

EGCG attenuated AMI-induced ferroptosis and improved myocardial ischemia injury, which was associated with reducing iron deposition and cTn I, inhibition of lipid peroxidation, decreasing TFR1 and ACSL4, and upregulating SLC7A11, FTH1 and GPX4. Meanwhile, EGCG pretreatment increased miR-450b-5p expression in ischemic myocardium. Further researches discovered that knockdown of miR-450b-5p partially compromised EGCG-generated protective effect in hypoxia HL-1 cells, while combination with miR-450b-5p mimic could strengthen the potency of EGCG on ischemic myocardium. The dual-luciferase test demonstrated that miR-450b-5p has binding to ACSL4. Furthermore, silencing of ACSL4 synergistically increased the cardioprotective effect of EGCG. More significantly, EGCG treatment regulated the ferroptosis-related proteins expression via miR-450b-5p/ACSL4 axis.

CONCLUSION

In summary, the present study evidently demonstrated that EGCG attenuates myocardial ischemia injury by targeting ferroptosis. Our work revealed the role of miR-450b-5p/ACSL4 axis in AMI for the first time. Further, it also elucidated the molecular mechanisms of EGCG on inhibiting ferroptosis greatly depend on the miR-450b-5p/ACSL4 axis, suggesting that EGCG may act as a novel anti-ferroptosis agent and exert a therapeutic role in AMI.

Vitamin E and Silymarin Reduce Oxidative Tissue Damage during Gentamycin-Induced Nephrotoxicity

Aminoglycoside antibiotics and gentamicin (GN), in particular, are still widely used in clinical practice. It is a well-known fact that GN causes nephrotoxicity, and redox disturbances are discussed as a factor in its side effects. Recently, a new type of cell oxidative death, named ferroptosis, was discovered; it is associated with iron accumulation in the cell, glutathione (GSH) depletion and inactivation of glutathione peroxidase-4 (GPX4), reactive oxygen species (ROS) increment with concomitant lipid peroxidation. In this regard, a possible connection between GN-induced renal damage, ferroptosis and the overall antioxidant status of the organism could be investigated. Moreover, due to its beneficial effects, GN is still one of the main choices as a therapeutic agent for several diseases, and the possible reduction of its side effects with the application of certain antioxidants will be of important clinical significance. The study was conducted with adult male white mice divided into several groups (n = 6). GN nephrotoxicity was induced by the administration of GN 100-200 mg/kg i.p. for 10 days. The control group received only saline. The other groups received either Vitamin E (400 mg/kg p.o.) or Silymarin (200 mg/kg p.o.) applied alone or together with GN for the same period. After the end of the study, the animals were sacrificed, and blood and tissue samples were taken for the assessment of biochemical parameters and antioxidant status, as well as routine and specific for GPX4 histochemistry examination. The experimental results indicate that GN-induced nephrotoxicity negatively modulates GPX4 activity and is associated with increased production of ROS and lipid peroxidation. The groups treated with antioxidants demonstrated preserved antioxidant status and better GPX4 activity. In conclusion, the inhibition of ROS production and especially the suppression of ferroptosis, could be of clinical potential and can be applied as a means of reducing the toxic effects of GN application.

Ferroptosis: A new mechanism of traditional Chinese medicine compounds for treating acute kidney injury

Acute kidney injury (AKI) is a major health concern owing to its high morbidity and mortality rates, to which there are no drugs or treatment methods, except for renal replacement therapy. Therefore, identifying novel therapeutic targets and drugs for treating AKI is urgent. Ferroptosis is an iron-dependent and lipid-peroxidation-driven regulatory form of cell death and is closely associated with the occurrence and development of AKI. Traditional Chinese medicine (TCM) has unique advantages in treating AKI due to its natural origin and efficacy. In this review, we summarize the mechanisms underlying ferroptosis and its role in AKI, and TCM compounds that play essential roles in the prevention and treatment of AKI by inhibiting ferroptosis. This review suggests ferroptosis as a potential therapeutic target for AKI, and that TCM compounds show broad prospects in the treatment of AKI by targeting ferroptosis.

Phytochemical Profile, Antioxidant, Antimicrobial and Cytoprotective Effects of Cornelian Cherry (Cornus mas L.) Fruit Extracts

Cornus mas L. is characterized by an increased quantity of bioactive compounds, namely polyphenols, monoterpenes, organic acids, vitamin C and lipophilic compounds such as carotenoids, being anciently used in the treatment of various diseases. This paper’s objectives were to characterize the phytochemical profile of Cornus mas L. fruits and to evaluate the in vitro antioxidant, antimicrobial and cytoprotective effects on renal cells exposed to gentamicin. As such, two ethanolic extracts were obtained. The resulting extracts were used to assess the total polyphenols, flavonoids and carotenoids through spectral and chromatographic methods. The antioxidant capacity was assessed using DPPH and FRAP assays. Due to the high content of phenolic compounds analyzed in fruits and the results obtained regarding antioxidant capacity, we decided to further use the ethanolic extract to investigate the in vitro antimicrobial and cytoprotective effects on renal cells stressed with gentamicin. The antimicrobial activity was assessed using agar well diffusion and broth microdilution methods, with great results regarding Pseudomonas aeruginosa. The cytotoxic activity was assessed using MTT and Annexin-V assays. According to the findings, extract-treated cells had a higher cell viability. However, at high concentrations, viability was shown to decline, most likely due to the extract and gentamicin’s additive effects.