Evaluating toxicity and decoding the underlying mechanisms of active compounds are crucial for drug development. In this study, we present an innovative, integrated approach that combines air flow-assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and spatial metabolomics to comprehensively investigate the nephrotoxicity and underlying mechanisms of nitidine chloride (NC), a promising anti-tumor drug candidate. Our quantitive AFADESI-MSI analysis unveiled the region specific of accumulation of NC in the kidney, particularly within the inner cortex (IC) region, following single and repeated dose of NC. High spatial resolution ToF-SIMS analysis further allowed us to precisely map the localization of NC within the renal tubule. Employing spatial metabolomics based on AFADESI-MSI, we identified over 70 discriminating endogenous metabolites associated with chronic NC exposure. These findings suggest the renal tubule as the primary target of NC toxicity and implicate renal transporters (organic cation transporters, multidrug and toxin extrusion, and organic cation transporter 2 (OCT2)), metabolic enzymes (protein arginine N-methyltransferase (PRMT) and nitric oxide synthase), mitochondria, oxidative stress, and inflammation in NC-induced nephrotoxicity. This study offers novel insights into NC-induced renal damage, representing a crucial step towards devising strategies to mitigate renal damage caused by this compound.

BACKGROUND: Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors marked a milestone in the breast cancer treatment. Due to the potential impact of adverse effects on treatment decisions and patient outcomes, careful consideration of the varying toxicities of CDK4/6 inhibitors is crucial, as three inhibitors-palbociclib, abemaciclib, and ribociclib-have been approved with differences in adverse event profiles. However, limitations in clinical trials call for urgent real-world safety studies to evaluate and compare the risk of adverse events (AEs) among these CDK4/6 inhibitors. Therefore, this study aimed to analyze AEs of CDK4/6 inhibitors and provide insights for clinical drug selection, using real world database.
METHODS: The AEs of CDK4/6 inhibitors in the FDA Adverse Event Reporting System (2015-2022) were analyzed. Four disproportionality methods were used to detect safety signals: reporting odds ratio (ROR), proportional reporting ratio, Bayesian Confidence Neural Network Propagation, and Multi-Item Gamma Poisson Shrinker. Venn analysis was used to compare and select common and specific AEs.
RESULTS: This study included 73,042 patients treated with palbociclib, 25,142 with ribociclib, and 7563 with abemaciclib. All three inhibitors had 27 common AEs. Palbociclib exhibited the highest ROR for hematologic toxicities, while ribociclib showed the highest ROR for macrocytosis, nail disorders, and hepatic lesions. Abemaciclib displayed the highest ROR for mucosal toxicity. Common signals for both palbociclib and ribociclib included hematologic toxicities, decreased immune responsiveness, and aphthous ulcers. Myelosuppression, oral pain, and pseudocirrhosis were common signals for palbociclib and abemaciclib. Anemia, hepatotoxicity, and pneumonitis were observed as common signals for ribociclib and abemaciclib. Furthermore, specific AEs associated with palbociclib included fatigue, alopecia, and stomatitis. For ribociclib, specific AEs included electrocardiogram QT prolongation, thrombocytopenia, and decreased hemoglobin. Abemaciclib was specifically linked to diarrhea, vomiting, and interstitial lung disease.
CONCLUSIONS: Our analysis revealed that palbociclib showed a higher risk of hematologic toxicity. Ribociclib showed higher risks of hepatotoxicity, nephrotoxicity, and QT prolongation. Abemaciclib showed higher risks of hepatotoxicity, gastrointestinal effects, interstitial lung disease, and thrombosis. These findings provide valuable insights for CDK4/6 inhibitor selection.

UNASSIGNED: Acute kidney injury (AKI) is a severe postoperative complication in patients undergoing major surgery. Proton pump inhibitors (PPIs) are used preoperatively as prophylaxis for postoperative gastrointestinal bleeding. Whether preoperative PPI use is associated with an increased risk of postoperative AKI remains uncertain.
UNASSIGNED: This retrospective cohort study used electronic medical records from the clinical data warehouse of Peking University First Hospital to screen all adult hospitalizations undergoing major surgery between 1 January 2018 and 31 December 2020. Exposure was preoperative PPI use, defined as PPI use within 7 days before major surgery. The primary outcome was postoperative AKI, defined as AKI occurring within 7 days after major surgery; secondary outcomes included in-hospital AKI and in-hospital mortality.
UNASSIGNED: A total of 21,533 patients were included in the study (mean [SD] age, 57.8 [15.0] years; 51.2% male), of which 944 (4.4%) were prescribed PPI within 7 days before major surgery (PPI users). Overall, 72 PPI users (7.6%) and 356 non-users (1.7%) developed postoperative AKI. After adjustment, preoperative PPI use was associated with an increased risk of postoperative AKI (adjusted OR, 1.47; 95% CI, 1.04-2.07) and in-hospital AKI (adjusted OR, 1.41; 95% CI, 1.03-1.94). Moreover, subgroup analyses showed that the risk of PPI on postoperative AKI was amplified by the concomitant use of non-steroidal anti-inflammatory drugs or diuretics. No significant difference was observed between preoperative PPI use and in-hospital mortality in the fully adjusted model (adjusted OR 1.63; 95% CI, 0.55-4.85).
UNASSIGNED: Preoperative PPI use was associated with an increased risk of AKI in patients undergoing major surgery. This risk may be enhanced by the concomitant use of other nephrotoxic drugs. Clinicians should weigh the pros and cons before initiating PPI prophylaxis.

Aristolochic acid nephropathy (AAN) is a rapidly progressive kidney disease caused by medical or environmental exposure to aristolochic acids (AAs). This study aimed to identify serum metabolites associated with the severity of acute AAN and investigate the underlying mechanisms. Male C57BL/6 mice were treated with vehicle and 3 doses of aristolochic acid I (AAI) (1.25, 2.5, and 5 mg/kg/d) for 5 days by intraperitoneal injection. The results showed that AAI dose-dependently increased blood urea nitrogen (BUN) and serum creatinine (Scr) levels and renal pathological damage. Non-targeted metabolomics revealed that differences in serum metabolite profiles from controls increased with increasing AAI doses. Compared with the control group, 56 differentially expressed metabolites (DEMs) that could be affected by all 3 doses of AAI were obtained. We further identified 13 DEMs whose abundance significantly correlated with Scr and BUN levels and had good predictive values for diagnosing AAI exposure. Among the 13 DEMs, lipids and lipid-like molecules constituted the majority. Western blotting found that AAI suppressed renal fatty acid oxidation (FAO)-related enzymes expression. In conclusion, these findings provided evidence for developing biomarkers for monitoring AAs exposure and AAN diagnosis and indicated activation of FAO as a potential direction for the treatment of AAN.

5-Fluorouracil (5-FU) is often used as a chemotherapeutic agent in treating tumors and is said to have adverse effects, including nephrotoxicity. Therefore, the present study aimed to evaluate the protective effects of Chlorella vulgaris (VL) and Saccharum officinarum L. (SOL) against 5-FU-induced nephrotoxicity in rats through the measurement of renal histology, kidney damage indicators, and antioxidant measures. A total of forty-eight male rats were allotted into six groups: group 1 acted as a control negative group (control), group 2 received 5-FU and worked as a control positive group (FU), group 3 received SOL 15 mL/kg (SOL), group 4 received VL 400 mg/kg (VL), group 5 received 5-FU+SOL (5-FU+SOL), and group 6 received 5-FU+VL (5-FU+VL). After fifteen days, blood and renal tissue specimens were collected for hematological, biochemical, molecular, and histopathological examinations. Findings of the current investigation showed that 5-FU leads to hematological alterations and kidney injury evinced by elevated serum concentrations of uric acid, creatinine, and urea (p < 0.01), and a marked increase in kidney MDA and NO levels with a reduction in kidney CAT, SOD and GSH activities (p < 0.05). Alterations of the histopathological structure of kidney tissue in the FU group were noticed compared to the other groups. 5-FU administration elevated expression levels of TNF-α, lipocalin 2, and KIM1 (p < 0.01) compared to the control ones. 5-FU-induced nephrotoxicity was ameliorated after treatment with SOL and VL via their free radical scavenging, potent antioxidant, and anti-inflammatory effects. In conclusion, our findings demonstrate that the treatment with SOL and VL significantly improved nephrotoxicity induced by 5-FU in rats.

BACKGROUND: Polymyxins have re-emerged as a last-resort therapeutic option for infections caused by carbapenem-resistant gram-negative bacteria. Nephrotoxicity induced by polymyxins is a significant limitation of its use in the clinic. Polymyxin B and colistin sulfate are two widely used active formulations of polymyxins. However, there is a lack of studies conducting a comparative assessment of nephrotoxicity between the two formulations. This study aimed to compare the nephrotoxicity of polymyxin B and colistin sulfate in critically ill patients.
METHODS: We conducted a retrospective cohort study among critically ill patients who received intravenous polymyxin B or colistin sulfate for over 48 h from January 2017 to January 2024. The primary outcome was the incidence of acute kidney injury (AKI) associated with polymyxins, and the secondary outcome was 30-day all-cause mortality. Additionally, the risk factors of polymyxins-induced AKI and 30-day all-cause mortality were identified by Cox proportional hazard regression analysis.
RESULTS: A total of 473 patients were included in this study. The overall incidence of AKI was significantly higher in patients who received polymyxin B compared to those who received colistin sulfate in the unmatched cohort (20.8% vs. 9.0%, p = 0.002) and in the propensity score matching cohort (21.1% vs. 7.0%, p = 0.004), respectively. However, there was no significant difference in 30-day all-cause mortality between the two groups. Polymyxin type, septic shock, and concomitant use of vasopressors were identified as independent risk factors for polymyxin-induced AKI.
CONCLUSIONS: The prevalence of AKI was higher among patients who received polymyxin B compared to those treated with colistin sulfate. However, there was no significant difference in 30-day all-cause mortality between the two groups. Further prospective, multicenter studies with larger sample sizes are needed to validate these findings.

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.

Lung cancer is the leading cause of cancer-related death worldwide, especially non-small cell lung cancer. Early diagnosis and better treatment choices have already provided a more promising prognosis for cancer patients. In targeted therapy, antagonists target specific genes supporting cancer growth, proliferation and metastasis. With the incorporation of targeted therapies in routine cancer therapy, it is imperative that the array of toxicities associated with these agents must be well-recognized and managed, especially since these toxicities are distinct from those seen with conventional cytotoxic agents. Drug-related nephrotoxicity has attracted attention when initiating cancer therapy. Our review aims to summarize the adverse renal effects caused by targeted therapy during lung cancer treatment, mainly focusing on EGFR and ALK tyrosine kinase inhibitors. Also, we discuss the possible mechanism of the side effect and provide managements to help improve the renal function in clinical practice.

Aflatoxin B1 (AFB1) not only causes significant losses in livestock production but also poses a serious threat to human health. It is the most carcinogenic among known chemicals. Pigs are more susceptible to AFB1 and experience a higher incidence. However, the molecular mechanism of the toxic effect of AFB1 remains unclear. In this study, we used assay for transposase-accessible chromatin using sequencing (ATAC-seq) and RNA-seq to uncover chromatin accessibility and gene expression dynamics in PK-15 cells during early exposure to AFB1. We observed that the toxic effects of AFB1 involve signaling pathways such as p53, PI3K-AKT, Hippo, MAPK, TLRs, apoptosis, autophagy, and cancer pathways. Basic leucine zipper (bZIP) transcription factors (TFs), including AP-1, Fos, JunB, and Fra2, play a crucial role in regulating the biological processes involved in AFB1 challenge. Several new TFs, such as BORIS, HNF1b, Atf1, and KNRNPH2, represent potential targets for the toxic mechanism of AFB1. In addition, it is crucial to focus on the concentration of intracellular zinc ions. These findings will contribute to a better understanding of the mechanisms underlying AFB1-induced nephrotoxicity and offer new molecular targets.

Nephrotoxicity remains a major adverse reaction of the anticancer drug cisplatin (CDDP) chemotherapy, which is an important risk factor for chronic renal disease. Ginsenoside Rh2 from Panax ginseng has been shown to protect against CDDP-induced nephrotoxicity in vivo, but its pharmacological effect on renal tubular epithelial cells is not clearly understood. This study examined the molecular mechanisms underlying the nephroprotective effects of Rh2 on CDDP-induced HK-2 cells and acute kidney injury (AKI) mice. As a result of Rh2 treatment, CDDP-induced HK-2 cells showed increased cell viability and reduced lactate dehydrogenase release. Moreover, Rh2 ameliorated CDDP-induced mitochondrial membrane potential, increased antioxidant enzyme activities, and reduced pro-inflammatory cytokine expression to reduce damage. Rh2 inhibited apoptosis and enhanced the antioxidant capacity of HK-2 cells by reducing proteins associated with endoplasmic reticulum (ER) stress, as well as by attenuating tunicamycin-induced ER stress. In addition, treatment of CDDP-induced AKI mice with Rh2 substantially reduced blood urea nitrogen and serum creatinine levels, attenuated histological damage of kidney. Further, Rh2 also improved kidney function by inhibiting ER stress to support in vitro findings. These results consistently demonstrated that Rh2 protects renal tubular epithelial cells from CDDP-induced nephrotoxicity and apoptosis by restoring ER homeostasis, which might suggest a therapeutic potential and providing new insights into AKI alternative therapies.