Raloxifene Protects Cisplatin-Induced Renal Injury in Mice via Inhibiting Oxidative Stress

Advances in understanding cisplatin-induced toxicity: Molecular mechanisms and protective strategies

Cisplatin, a widely used chemotherapeutic agent, has proven efficacy against various malignancies. However, its clinical utility is hampered by its dose-limiting toxicities, including nephrotoxicity, ototoxicity, neurotoxicity, and myelosuppression. This review aims to provide a comprehensive overview of cisplatin toxicity, encompassing its underlying mechanisms, risk factors, and emerging therapeutic strategies. The mechanisms of cisplatin toxicity are multifactorial and involve oxidative stress, inflammation, DNA damage, and cellular apoptosis. Various risk factors contribute to the interindividual variability in susceptibility to cisplatin toxicity. The risk of developing cisplatin-induced toxicity could be related to pre-existing conditions, including kidney disease, hearing impairment, neuropathy, impaired liver function, and other comorbidities. Additionally, this review highlights the emerging therapeutic strategies that could be applied to minimize cisplatin-induced toxicities and aid in optimizing cisplatin treatment regimens, improving patient outcomes, and enhancing the overall quality of cancer care.

Bipyraloxifene - a modified raloxifene vector against triple-negative breast cancer

Raloxifene, a selective oestrogen receptor modulator (SERM), has demonstrated efficacy in the prevention and therapy of oestrogen receptor-positive (ER+) breast cancer, with some degree of effectiveness against triple-negative forms. This suggests the presence of oestrogen receptor-independent pathways in raloxifene-mediated anticancer activity. To enhance the potential of raloxifene against the most aggressive breast cancer cells, hybrid molecules combining the drug with a metal chelator moiety have been developed. In this study, we synthetically modified the structure of raloxifene by incorporating a 2,2'-bipyridine (2,2'-bipy) moiety, resulting in [6-methoxy-2-(4-hydroxyphenyl)benzo[b]thiophen-3-yl]-[4-(2,2'-bipyridin-4'-yl-methoxy)phenyl]methanone (bipyraloxifene). We investigated the cytotoxic activity of both raloxifene and bipyraloxifene against ER+ breast adenocarcinomas, glioblastomas, and a triple-negative breast cancer (TNBC) cell line, elucidating their mode of action against TNBC. Bipyraloxifene maintained a mechanism based on caspase-mediated apoptosis but exhibited significantly higher activity and selectivity compared to the original drug, particularly evident in triple-negative stem-like MDA-MB-231 cells.

Rosuvastatin and diosmetin inhibited the HSP70/TLR4 /NF-κB p65/NLRP3 signaling pathways and switched macrophage to M2 phenotype in a rat model of acute kidney injury induced by cisplatin

Numerous efforts to manage acute kidney injury (AKI) were unsuccessful because its pathophysiology is still poorly understood. Thus, our research hotspot was to explore the possible renoprotective effects of rosuvastatin (Ros) and diosmetin (D) on macrophage polarization and the role of HSP70/TLR4/MyD88/NF-κB p65/NLRP3/STAT3 signaling in cis-induced AKI and study the activity of D against uropathogenic bacteria. Fifty-four albino male rats were randomized into 9 groups equally: Control, Ros, D20, D40, untreated Cis, and Cis groups cotreated with Ros, D20, D40 and Ros+D40 for 10 days. Our results indicated that Ros and D, in a dose-dependent manner, markedly restored body weight, systolic blood pressure, and renal histological architecture besides significantly upregulated SOD levels, expression of anti-inflammatory CD163 macrophages, arginase1levels, IL-10 levels,STAT3 and PCNA immunoreactivity. Also, they significantly downregulated renal index, serum urea, serum creatinine, serum cystatin c, inflammatory biomarkers (C reactive protein, IL1β & TNF-α), MDA levels, HSP70/TLR4/MyD88/NF-κB p65/NLRP3 expressions, proinflammatory CD68 macrophages and caspase-3 immunoreactivity, resulting in a reversal of cis-induced renal damage. These findings were further confirmed by molecular docking that showed the binding affinity of Ros and D towards TLR4 and NLRP3. Furthermore, D had antibacterial action with a minimum inhibitory concentration ranging from 128 to 256 µg/mL and caused a delay in the growth of the tested isolates, and negatively affected the membrane integrity. In conclusion, Ros and D had antioxidant, anti-inflammatory and antiapoptotic properties and switched macrophage from proinflammatory CD68 to anti-inflammatory CD163. Additionally, the targeting of HSP70/TLR4/MyD88/NF-κB p65/NLRP3/STAT3 signals are effective therapeutic strategy in AKI.

Apigenin Ameliorates Hyperuricemia and Renal Injury through Regulation of Uric Acid Metabolism and JAK2/STAT3 Signaling Pathway

Hyperuricemia (HUA) is a kind of metabolic disease with high incidence that still needs new countermeasures. Apigenin has uric-lowering and kidney-protective activities, but how apigenin attenuates HUA and renal injury remains largely unexploited. To this end, an acute HUA mouse model was established by intraperitoneal injection of potassium oxazinate and oral administration with hypoxanthine for 7 consecutive days. Apigenin intervention decreased serum uric acid (UA), creatinine (CRE), blood urea nitrogen (BUN), interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor (TNF-α), interleukin-18 (IL-18), liver xanthine oxidase (XOD), and urine protein levels, and increased serum interleukin-10 (IL-10) and urine UA and CRE levels in HUA mice. Moreover, administration of apigenin to HUA mice prevented renal injury, decreased renal glucose transporter 9 (GLUT9) and urate anion transporter 1 (URAT1) levels, and increased renal organic anion transporter 1 (OAT1). These alterations were associated with an inhibition of IL-6, phospho-janus kinase 2 (P-JAK2), phospho-signal transducer, and activator of transcription 3 (P-STAT3), and suppression of cytokine signaling 3 (SOCS3) expression in the kidneys. Additionally, the molecular docking results showed that apigenin had strong binding capacity with UA transporters and JAK2 proteins. In summary, apigenin could improve UA metabolism and attenuate renal injury through inhibiting UA production, promoting excretion, and suppressing the JAK2/STAT3 signaling pathway in HUA mice. The results suggest that apigenin may be a suitable drug candidate for management of HUA and its associated renal injury.

The diminution and modulation role of water-soluble gallic acid-carboxymethyl chitosan conjugates against the induced nephrotoxicity with cisplatin

The toxicity of cisplatin (CDDP) toward the renal tubules and its severe effects on the proximal tubules limits its further use in cancer therapy. The current study was undertaken to evaluate the protective effects of gallic acid-grafted O-carboxymethyl chitosan (GA@CMCS) against nephrotoxicity induced by CDDP in rats. Renal injury was assessed in the GA@CMCS/CDDP-treated rats using kidney injury molecule-1 (KIM-1). Moreover, the levels of reduced glutathione (GSH), malondialdehyde (MDA), and nitric oxide (NO) were measured. The comet assay was performed to measure the DNA damage. The renoprotective activity of GA@CMCS was supported by histo- and immuno-pathological studies of the kidney. GA@CMCS significantly normalized the increases in kidney homogenate of KIM-1, MDA, and NO-induced by CDDP and significantly increased GSH as compared with the CDDP group. GA@CMCS also significantly protects rat kidneys from CDDP-induced histo- and immuno-pathological changes. Both biochemical findings and histo- and immuno-pathological evidence showed the renoprotective potential of GA@CMCS against CDDP-induced oxidative stress, inflammation, and renal dysfunction in rats. In conclusion, GA@CMCS has been shown to mitigate the nephrotoxicity impact of CDDP in cancer therapy.