Cisplatin and AKI: an ongoing battle with new perspectives—a narrative review

Glycoengineered stem cell-derived extracellular vesicles for targeted therapy of acute kidney injury

Acute kidney injury (AKI) is associated with high morbidity and mortality rates, primarily due to the lack of effective therapeutic options for kidney repair. To restore the biological function of injured kidney, there is a need to protect renal tubular epithelial cells (RTECs) and regulate M1 macrophages, responsible for progress of AKI. Herein, based on metabolic glycoengineering-mediated click chemistry, we prepare the engineered extracellular vesicles (pSEVs), derived from PEGylated hyaluronic acid (HA)-modified mesenchymal stem cells. Owing to their cell-protective and anti-inflammatory properties, pSEVs effectively prevent the apoptosis of RTECs and inhibit the polarization of macrophages into an inflammatory phenotype in vitro. When systemically administered into the cisplatin-induced AKI animal model, pSEVs selectively accumulate in injured kidneys via HA-mediated binding to CD44 and toll-like receptor4 which are over-expressed on RTECs and M1 macrophages, respectively. This targeted delivery efficiently alleviates AKI-related symptoms, as evidenced by delayed kidney weight reduction, and decreased levels of creatinine, blood urea nitrogen, and neutrophil gelatinase-associated lipocalin. Overall, pSEVs show potent anti-inflammatory effects and specific targeting to injured kidneys, presenting a considerable potential as the therapeutics for AKI.

The nephroprotective effect of metformin with cisplatin in bladder cancer: randomized clinical trial

PURPOSE

Cisplatin-based combination chemotherapy is the mainstay treatment strategy in various forms of carcinomas and sarcomas. However, its dosage and therapeutic efficacy are significantly limited by its nephrotoxicity. Based on metformin renal benefits in different studies, the study aims to determine safety and the potential nephroprotective effect of metformin when used with cisplatin in patients with bladder cancer.

METHODS

This was a prospective, randomized, parallel, controlled, open-label study in which 78 chemotherapy naïve bladder cancer patients aged 18-65 years and would receive gemcitabine/cisplatin regimen were selected and randomly assigned to treatment or control group in 1:1 allocation. Both groups were receiving cisplatin standard-of-care regimen, whereas metformin (500 mg, twice daily) was added to the treatment group's regimen only. Patients were prospectively followed up for four cycles of gemcitabine/cisplatin with assessment of renal function tests, serum neutrophil gelatinase-associated lipocalin (NGAL), cystatin-c, and metformin's adverse effects.

RESULTS

Serum creatinine, serum NGAL, and cystatin-C significantly increased in the control group only (P < 0.001). Estimated glomerular filtration rate (eGFR) significantly declines in the control group only (P < 0.001). On the contrary, serum NGAL significantly improved in the treatment group (P = 0.02) with stable and normal mean value of serum creatinine, eGFR, and cystatin-C without a concomitant significant increase in adverse events, such as hypoglycemia, gastrointestinal symptoms, or weight loss compared to the control group.

CONCLUSION

Metformin prevented renal damage and deterioration in kidney function in cisplatin-treated patients. Therefore, it is a promising agent in reducing cisplatin-induced nephrotoxicity. The study was registered in ClinicalTrials.gov on December, 16, 2023, Identifier Number NCT06215976.

Diagnostic and Prognostic Potential of SH3YL1 and NOX4 in Muscle-Invasive Bladder Cancer

Bladder cancer, especially muscle-invasive bladder cancer (MIBC), poses significant treatment challenges due to its aggressive nature and poor prognosis, often necessitating cisplatin-based chemotherapy. While cisplatin effectively reduces tumor burden, its nephrotoxic effects, specifically cisplatin-induced acute kidney injury (AKI), limit its clinical use. This study investigates SH3YL1 as a potential biomarker for bladder cancer progression and AKI. Plasma and urine SH3YL1 levels were measured in bladder cancer patients undergoing cisplatin treatment, showing elevated baseline levels compared to controls, suggesting a link with bladder cancer pathology rather than cisplatin-induced AKI. Functional network and Gene Ontology (GO) enrichment analyses identified SH3YL1's interactions with NADPH oxidase pathways, particularly NOX family genes, and highlighted its roles in cell adhesion, migration, and cytoskeletal organization-processes critical for tumor invasiveness. Notably, SH3YL1 and NOX4 expression were significantly higher in MIBC than in non-muscle-invasive bladder cancer (NMIBC), with a strong correlation between SH3YL1 and NOX4 (r = 0.62) in MIBC, suggesting a subtype-specific interaction. Kaplan-Meier survival analysis using The Cancer Genome Atlas bladder cancer (TCGA-BLCA) data further demonstrated that low SH3YL1 expression is significantly associated with poor overall and disease-specific survival in MIBC patients, reinforcing its role as a prognostic biomarker. In conclusion, SH3YL1 is a promising biomarker for identifying the invasive characteristics of MIBC and predicting patient outcomes. These findings underscore the importance of SH3YL1-NOX4 pathways in MIBC and suggest the need for further research into targeted biomarkers for bladder cancer progression and cisplatin-induced AKI to improve patient outcomes in high-risk cases.

Smilax glabra roxb. alleviates cisplatin-induced acute kidney injury in mice by activating the Nrf2/HO-1 Signalling Pathway

BACKGROUND

Owing to its remarkable efficacy, cisplatin (CDDP) is widely used as a chemotherapeutic drug in clinical cancer treatment; however, its severe nephrotoxicity often leads to acute kidney injury (AKI), in turn adversely affecting patient treatment and quality of life. Smilax glabra Roxb. (TFL), a Chinese herbal medicine, has various pharmacological effects, including antitumour, anti-inflammatory, and antioxidant activities, with the antioxidant activity being of useful in the detoxification of heavy metal toxicity.

AIM

This study aimed to investigate, for the first time, the nephroprotective effects of TFL in alleviating CDDP-induced AKI and to elucidate its underlying mechanisms.

METHODS

In vitro and in vivo models of AKI were established using CDDP induction. For the in vivo model, CDDP (20 mg/kg) was intraperitoneally injected on day 7 to induce AKI. TFL treatment was administered daily at doses of 1.95 and 3.9 g/kg starting from the day 1 and continuing for 10 consecutive days. Blood samples were collected on day 10 after 72-h of CDDP injection for analysis. Kidney pathology was observed using haematoxylin and eosin (HE) staining, and mitochondrial ultrastructure was assessed using transmission electron microscopy. The expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2), HO-1, NQO1, caspase-3, and cytochrome C (CYT-C) were determined using western blotting, PCR, and immunofluorescence (IF). Adenosine triphosphate (ATP) levels, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) were measured using the corresponding kits. Lastly, reverse validation of the Nrf2/HO-1 pathway was performed using the Nrf2-specific inhibitor, ML385.

RESULTS

After induction with 40 μM CDDP, HK2 cells showed obvious mitochondrial damage, and the protein and mRNA expressions of Nrf2, HO-1, and NQO1 were inhibited, but gradually increased with TFL treatment. Furthermore, CDDP-induced AKI in mice was similar to the observations in the in vitro model using HK2 cells. The protective effects of TFL were reversed with ML385 therapy.

CONCLUSION

In both in vivo and in vitro experiments, TFL activated the Nrf2/HO-1 signalling pathway, promoting the expression of antioxidant enzymes and thereby ameliorating CDDP-induced oxidative stress, mitochondrial dysfunction and renal cell apoptosis.

Methyltransferase-like 3 represents a prospective target for the diagnosis and treatment of kidney diseases

Kidney disease is marked by complex pathological mechanisms and significant therapeutic hurdles, resulting in high morbidity and mortality rates globally. A deeper understanding of the fundamental processes involved can aid in identifying novel therapeutic targets and improving treatment efficacy. Current comprehensive data analyses indicate the involvement of methyltransferase-like 3 (METTL3) and its role in RNA N6-methyladenosine methylation in various renal pathologies, including acute kidney injury, renal fibrosis, and chronic kidney disease. However, there is a paucity of thorough reviews that clarify the functional mechanisms of METTL3 and evaluate its importance in enhancing therapeutic outcomes. This review seeks to systematically examine the roles, mechanisms, and potential clinical applications of METTL3 in renal diseases. The findings presented suggest that METTL3 is implicated in the etiology and exacerbation of kidney disorders, affecting their onset, progression, malignancy, and responsiveness to chemotherapeutic agents through the regulation of specific genetic pathways. In conclusion, this review underscores a detrimental correlation between METTL3 and kidney diseases, highlighting the therapeutic promise of targeting METTL3. Additionally, it offers critical insights for researchers concerning the diagnosis, prognosis, and treatment strategies for renal conditions.

Omega-3 polyunsaturated fatty acids protect against cisplatin-induced nephrotoxicity by activating the Nrf2 signaling pathway

Nephrotoxicity is a prevalent side effect observed in patients undergoing chemotherapy. The pathogenesis of chemotherapy-induced nephrotoxicity involves various factors such as oxidative stress, DNA damage, inflammation, and apoptosis. Omega-3 polyunsaturated fatty acids (ω-3 PUFAs), particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), possess anti-inflammatory and antioxidant properties. This study investigated the effects of EPA and DHA, either alone or in combination, on cisplatin-induced nephrotoxicity in mice, as well as their underlying mechanisms of action. The combined administration of EPA and DHA demonstrated superior efficacy in mitigating cisplatin-induced nephrotoxicity compared to administration alone, including the reduction of oxidative damage, inflammation, and apoptosis. Moreover, the combination of EPA and DHA suppressed inflammation and prevented the development of chronic kidney fibrosis during prolonged observations following repeated cisplatin administration. Mechanistically, ω-3 PUFAs enhance the expression of antioxidant genes by activating the p62-Keap1-Nrf2 signaling pathway. Furthermore, Nrf2 activation can inhibit the cisplatin-induced p53 apoptosis signal by upregulating the expression of MDM2 in renal tubular epithelial cells. Consequently, ω-3 PUFAs exert a protective effect against cisplatin-induced renal injury through activating the Nrf2 signaling pathway, suggesting that ω-3 PUFAs intake holds promise as a therapeutic strategy for combating cisplatin-induced nephrotoxicity.

PARVB deficiency alleviates cisplatin-induced tubular injury by inhibiting TAK1 signaling

Cisplatin-induced renal tubular injury largely restricts the wide-spread usage of cisplatin in the treatment of malignancies. Identifying the key signaling pathways that regulate cisplatin-induced renal tubular injury is thus clinically important. PARVB, a focal adhesion protein, plays a crucial role in tumorigenesis. However, the function of PARVB in kidney disease is largely unknown. To investigate whether and how PARVB contributes to cisplatin-induced renal tubular injury, a mouse model (PARVB cKO) was generated in which PARVB gene was specifically deleted from proximal tubular epithelial cells using the Cre-LoxP system. In this study, we found depletion of PARVB in proximal tubular epithelial cells significantly attenuates cisplatin-induced renal tubular injury, including tubular cell death and inflammation. Mechanistically, PARVB associates with transforming growth factor-β-activated kinase 1 (TAK1), a central regulator of cell survival and inflammation that is critically involved in mediating cisplatin-induced renal tubular injury. Depletion of PARVB promotes cisplatin-induced TAK1 degradation, inhibits TAK1 downstream signaling, and ultimately alleviates cisplatin-induced tubular cell damage. Restoration of PARVB or TAK1 in PARVB-deficient cells aggravates cisplatin-induced tubular cell injury. Finally, we demonstrated that PARVB regulates TAK1 protein expression through an E3 ligase ITCH-dependent pathway. PARVB prevents ITCH association with TAK1 to block its ubiquitination. Our study reveals that PARVB deficiency protects against cisplatin-induced tubular injury through regulation of TAK1 signaling and indicates targeting this pathway may provide a novel therapeutic strategy to alleviate cisplatin-induced kidney damage.

Time-course analysis of cisplatin induced AKI in preclinical models: implications for testing different sources of MSCs

BACKGROUND

Kidneys are at risk from drug-induced toxicity, with a significant proportion of acute kidney injury (AKI) linked to medications, particularly cisplatin. Existing cytoprotective drugs for cisplatin-AKI carry side effects, prompting a search for better biological therapies. Mesenchymal Stem Cells (MSCs) are under consideration given their regenerative properties, yet their clinical application has not achieved their full potential, mainly due to variability in the source of MSC tested. In addition, translating treatments from rodent models to humans remains challenging due to a lack of standardized dosing and understanding potential differential responses to cisplatin between animal strains.

METHOD

In the current study, we performed a time-course analysis of the effect of cisplatin across different mouse strains and evaluated gender related differences to create a robust preclinical model that could then be used to explore the therapeutic efficacy of different sources of MSCs for their ability to reverse AKI.

RESULT

Our data indicated that different mouse strains produce differential responses to the same cisplatin dosing regimen. Despite this, we did not observe any gender-related bias towards cisplatin nephrotoxicity. Furthermore, our time-course analysis identified that cisplatin-induced inflammation was driven by a strong CXCL1 response, which was used as a putative biomarker to evaluate the comparative therapeutic efficacy of different MSC sources in reversing AKI. Our data indicates that UC-MSCs have a stronger anti-inflammatory effect compared to BM-MSCs and AD-MSCs, which helped to ameliorate cisplatin-AKI.

CONCLUSION

Overall, our data underscores the importance of using an optimized preclinical model of cisplatin-AKI to test different therapies. We identified CXCL1 as a potential biomarker of cisplatin-AKI and identified the superior efficacy of UC-MSCs in mitigating cisplatin-AKI.

Phytochemical profiling and nephroprotective potential of ethanolic leaf extract of Polyalthia longifolia against cisplatin-induced oxidative stress in rat model

ETHNOPHARMACOLOGICAL RELEVANCE

Kidney problems are becoming more common globally and are considered a major health issue in the modern world with high mortality rate. Polyalthia longifolia (Sonn.) Thwaites is a tropical ethnomedicinal plant used to treat various diseases like diabetes, hypertension and urinary disorders and possess antioxidant and anti-inflammatory properties.

AIM OF THE STUDY

This study aimed to investigate the phytochemical composition of 70% ethanolic leaf extract of Polyalthia longifolia (Sonn.) Thwaites (PL) and evaluates its nephroprotective effects against cisplatin-induced nephrotoxicity in Wistar rats.

MATERIALS AND METHODS

The leaves of PL were extracted with 70% ethanol and performed the phytochemical profiling using Liquid Chromatography-Mass Spectrometry (LC-MS). The nephroprotective effect of PL leaf extract was evaluated at three doses (150, 300 and 600 mg/kg, p.o.) for 14 days against cisplatin toxicity (16 mg/kg, i.p., once) in male Wistar rats. Body and kidney weight indices, kidney function markers and lipid profile markers in serum, and oxidative stress markers in kidney tissue were performed along with the histopathological analysis of kidney.

RESULTS

The LC-MS chromatograph confirmed the presence of various phytocompounds include N-Methylhernagine (aporphine alkaloid), 4-Acetamidobutanoic acid (gamma amino acid) and choline, etc. in the PL leaf extract. Exposure of cisplatin (16 mg/kg, i.p., once only) to the animals significantly elevated the levels of kidney functional markers (i.e. serum urea, uric acid, creatinine) and the lipid markers (triglyceride and total cholesterol) in blood circulation with depletion of serum albumin which were reversed by the therapy of PL leaf extract (150, 300 and 600 mg/kg) in dose-dependent manner. The altered level of body and kidney weight in cisplatin treated group was also restored by the therapy. PL leaf extract effectively improved the antioxidant defense system of kidney at all doses by restoring the levels of tissue glutathione, superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase with the dose-dependent reduction of lipid peroxidation against cisplatin-induced renal oxidative stress. The histopathological observations also showed the significant recovery in cellular morphology after PL treatment when compared to the cisplatin toxicity group. The highest dose 600 mg/kg of PL leaf extract showed more pronounced renal recovery (p < 0.001) followed by other two doses, which was similar to the silymarin treatment group (a reference drug) against nephrotoxicity.

CONCLUSION

The results of this study revealed the nephroprotective effects of PL leaves against cisplatin-induced nephrotoxicity by reversing the level of biochemical markers and mitigating oxidative stress as well as improving the architecture of renal tissues. This renal protection by PL might be due to the synergistic effect of its phytoconstituents and antioxidant efficacy.

Potential therapeutic applications of circular RNA in acute kidney injury

Acute kidney injury (AKI) is a common clinical syndrome characterized by a rapid deterioration in renal function, manifested by a significant increase in creatinine and a sharp decrease in urine output. The incidence of morbidity and mortality associated with AKI is on the rise, with most patients progressing to chronic kidney disease or end-stage renal disease. Treatment options for patients with AKI remain limited. Circular RNA (circRNA) is a wide and diverse class of non-coding RNAs that are present in a variety of organisms and are involved in gene expression regulation. Studies have shown that circRNA acts as a competing RNA, is involved in disease occurrence and development, and has potential as a disease diagnostic and prognostic marker. CircRNA is involved in the regulation of important biological processes, including apoptosis, oxidative stress, and inflammation. This study reviews the current status and progress of circRNA research in the context of AKI.

Pharmacotherapy considerations in patients who develop acute kidney injury during anti-cancer therapy

INTRODUCTION

Acute kidney injury (AKI) frequently develops in patients receiving cancer therapy and requires a wide differential diagnosis due to possible role of unique cancer and drug-related factors, in addition to common pre- and post-renal causes. Rapid development of new molecular targeted anti-cancer drugs and immunotherapies has opened unprecedented possibilities of treatment at the price of an increased spectrum of renal side effects.

AREAS COVERED

The present review aims at providing a state-of-the-art picture of AKI in cancer patient (PubMed and Embase libraries were searched from inception to January 2024), with a focus on differential diagnosis and management of diverse clinical settings. Reports of parenchymal AKI due to glomerular, microvascular, tubular and interstitial damage have been constantly increasing. Complex electrolyte and acid-base disorders can coexist. The role of renal biopsy and possible therapeutic approaches are also discussed.

EXPERT OPINION

Onconephrology has become an important subspecialty of clinical nephrology, requiring constantly updated skills and a high degree of interdisciplinary integration to tackle diagnostic challenges and even therapeutic and ethical dilemmas. Integrated onconephrological guidelines and availability of biomarkers may provide new tools for management of this unique type of patients in the near future.