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 flowassisted 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.
Shu YangZhonghua WangYanhua LiuXin ZhangHang ZhangZhaoying WangZhi ZhouZeper Abliz
Ototoxicity and nephrotoxicity are the most prevalent side effects of aminoglycoside antibiotics(gentamicin,amikacin,neomycin)and platinum anti-tumor drugs(cisplatin,carboplatin).The inner ear and kidney share similarities in drug deposition and toxicity,but the underlying pathophysiological mechanisms remain unclear.Investigating the shared mechanisms and metabolic alterations in these distinct organs will provide valuable insights for clinical therapy.A strong correlation has been identified between the spatiotemporal accumulation patterns of neomycin and the specific occurrence of lipid metabolism disorders in these two organs.The primary allocation of neomycin to mitochondria results in a notable escalation in the accumulation of lipid droplets(LDs)and more interactions between mitochondria and LDs,leading to a sequence of disturbances in lipid metabolism,such as increased lipid ROS and the blocked transfer of fatty acids from LDs to mitochondria.PGC-1αdeficiency worsens the neomycin-induced disorders in lipid metabolism and intensifies the pathological interactions between mitochondria and LDs,as indicated by the exacerbated disturbance of dynamic LD turnover,increased level of oxidized lipids and decreased use of fatty acids.This investigation provides a fresh perspective on the lipid metabolic dysfunction related to mitochondria-LD interactions in drug-induced ototoxicity and nephrotoxicity,potentially providing novel avenues for intervention strategies.
Nanoplastics(NPs)can accumulate in the kidney and cause kidney injury,but the multi-organ interaction mechanism and preventive measures of kidney injury are still unclear.In this study,in vivo(60μg/day,42 days)and in vitro(0.4μg/μL,24 h)exposure models of polystyrene nanoplastics(PS-NPs,80 nm)in mice and human kidney cortex proximal tubule epithelial cells(HK-2 cells)were established,respectively.Our study revealed that PS-NPs caused obvious pathological changes and impaired renal function in mice,which were related to lipid metabolism disorders mediated by intestinal flora.Desulfovibrionales-fatty acid synthase(Fasn)-docosahexaenoic acid(DHA)pathway may be one of the mechanisms of kidney injury in mice.Importantly,we also found that melatonin attenuates PS-NPs-induced nephrotoxicity by modulating lipid metabolism disorders(represented by DHA)and affects Fasn expression.In conclusion,our study revealed the important role of intestinal flora-mediated lipid metabolism in PS-NPs-induced nephrotoxicity and preliminarily provided potential key gene targets and effective preventive measures for PS-NPs-induced nephrotoxicity.