Regulation of PUMA-alpha by p53 in cisplatin-induced renal cell apoptosis

Unleashing the therapeutic power of verteporfin-eluting stents: modulating YAP signaling to combat carotid artery restenosis and cerebral watershed infarction

Carotid artery stenosis is the main cause of cerebral watershed infarction (CWI). In recent years, increasing attention has been given to treating this condition. The present study aimed to investigate how Verteporfin-eluting stent (VPES) modulates the YAP signaling pathway to inhibit restenosis of the carotid artery and alleviate CWI. Through transcriptome sequencing and functional experiments, it was found that VP could regulate the Yes-associated protein (YAP) signaling pathway and effectively suppress the proliferation and migration of smooth muscle cells (SMCs). Further investigation revealed that VPES could inhibit carotid artery restenosis through the YAP signaling pathway in a rabbit model, reducing the occurrence of CWI.

Doxepin as OCT2 inhibitor ameliorates inflammatory response and modulates PI3K/Akt signaling associated with cisplatin-induced nephrotoxicity in rats

Organic cationic transporter 2 (OCT2) was identified as the main transporter involved in the accumulation of cisplatin (CP) in the proximal tubular renal cells, resulting in nephrotoxicity. Doxepin (DOX) is a tricyclic agent with an inhibitory effect on OCT2. This study aimed to explore the possible mechanisms of the renoprotective role of DOX toward CP-induced nephrotoxicity. Rats were randomly divided into six groups: group 1, control; group 2, CP; groups 3, 4, and 5 were treated with graded doses of DOX (5, 10, and 20 mg/kg, respectively) intraperitoneally (ip) once daily for 10 consecutive days and group 6 was treated only with DOX (20 mg/kg). On the seventh day, a single injected dose of CP (10 mg/kg, ip) was given to the rats in groups 2-5. Seventy-two hours after CP injection, rats were sacrificed, and the kidneys were removed for histological and biochemical measurements. DOX ameliorated the CP-induced histopathological alterations. DOX significantly reduced the expression of OCT2, lipid peroxidation marker (MDA), and inflammatory cytokines, including TNF-α, IL-6, IL-1, IL-2, and IL-1β, and increased the activity of antioxidant enzymes. In addition, pre- and co-treatment with DOX significantly reduced the CP-mediated apoptotic effect by reducing the renal tissue expression of BAX and caspase-3 levels, upregulating the expression of Bcl-2, and modulating the phosphorylation of PI3K/Akt signaling cascade. DOX exerts a nephroprotective impact against CP-mediated nephrotoxicity via the inhibition of OCT2, suppression of inflammation, oxidative stress, and apoptotic markers, and modulation of PI3K/Akt signaling cascade.

Regulation of fibroblast phenotype in osteoarthritis using CDKN1A-loaded copper sulfide nanoparticles delivered by mesenchymal stem cells

This study aimed to investigate the regulation of fibroblast phenotypes by mesenchymal stem cells (MSCs) delivering copper sulfide (CuS) nanoparticles (NPs) loaded with CDKN1A plasmids and their role in cartilage repair during osteoarthritis (OA). Single-cell RNA sequencing data from the GEO database were analyzed to identify subpopulations within the OA immune microenvironment. Quality control, filtering, principal component analysis (PCA) dimensionality reduction, and tSNE clustering were performed to obtain detailed cell subtypes. Pseudotime analysis was used to understand the developmental trajectory of fibroblasts, and GO/KEGG enrichment analyses highlighted biological processes related to fibroblast function. Transcriptomic data and WGCNA identified CDKN1A as a key regulatory gene. A biomimetic CuS@CDKN1A nanosystem was constructed and loaded into MSCs to create MSCs@CuS@CDKN1A. The characterization of this system confirmed its efficient cellular uptake by fibroblasts. In vitro experiments demonstrated that MSCs@CuS@CDKN1A significantly modulated fibroblast phenotypes and improved the structure, proliferation, reduced apoptosis, and enhanced migration of IL-1β-stimulated chondrocytes. In vivo, an OA mouse model was treated with intra-articular injections of MSCs@CuS@CDKN1A. Micro-CT scans revealed a significant reduction in osteophyte formation and improved joint space compared with control groups. Histological analysis, including H&E, Safranin O-Fast Green, and toluidine blue staining, confirmed improved cartilage integrity, whereas the International Osteoarthritis Research Society (OARSI) scoring indicated reduced disease severity. Immunofluorescence showed upregulated CDKN1A expression, decreased MMP13, and reduced α-SMA expression in fibroblast subtypes. Major organs exhibited no signs of toxicity, confirming the biocompatibility and safety of the treatment. These findings suggest that MSCs@CuS@CDKN1A can effectively regulate fibroblast activity and promote cartilage repair, providing a promising therapeutic strategy for OA treatment.NEW & NOTEWORTHY This study introduces MSCs@CuS@CDKN1A, a nanoengineered MSC platform that targets fibroblast phenotypes in osteoarthritis (OA). By modulating CDKN1A expression, this innovative approach not only enhances cartilage repair but also effectively mitigates fibroblast-driven inflammation, marking a significant advancement in OA therapeutics with demonstrated efficacy and biocompatibility.

Chemoprotective Mechanism of Sodium Thiosulfate Against Cisplatin-Induced Nephrotoxicity Is via Renal Hydrogen Sulfide, Arginine/cAMP and NO/cGMP Signaling Pathways

Cisplatin is a common and highly effective chemotherapeutic agent whose nephrotoxic side effect is well-characterized. Sodium thiosulfate (STS), an FDA-approved hydrogen sulfide (H2S) donor drug, is emerging as a chemoprotective agent against cisplatin-induced nephrotoxicity (CIN). In this study, we investigated the chemoprotective mechanism of STS in a rat model of CIN. Twenty-five male Sprague Dawley rats were randomly assigned to the following groups: HC: Healthy control (received 10 mL/kg/day of 0.9% saline intraperitoneally (ip), [n = 5]), CIN: Cisplatin (received single dose of 7 mg/kg cisplatin ip [n = 5]); CIN + PAG: Cisplatin and daily ip administration of 40 mg/kg of the H2S inhibitor, DL-propargylglycine (PAG) for 28 days (n = 5); CIN + PAG + STS: Cisplatin and daily PAG and STS (150 µM) ip injection for 28 days; CIN + STS: Cisplatin and daily STS ip administration for 28 days (n = 5). Rats in each group were kept in metabolic cages for 24 h on day 0, 14 and 29 after cisplatin administration for urine collection. Rats were then euthanized, and kidney and blood samples were collected for analysis. Histologically, CIN was characterized by glomerular and tubular injury and significant macrophage influx and tubular apoptosis, as well as markedly increased levels of plasma and renal IL-1β, IL-6 and TNF-α and impaired renal antioxidant status compared to HC rats (p < 0.001). These pathological changes were exacerbated in CIN + PAG rats and were strongly reduced in CIN + PAG + STS rats relative to CIN + PAG rats (p < 0.01), while superior renal protection was observed in CIN + STS rats. Functionally, CIN was evidenced by markedly increased levels of serum creatinine and BUN, and significantly decreased urine creatinine, renal creatinine clearance, as well as electrolyte imbalance and urinary concentrating defect in comparison with HC (p < 0.01). These functional changes worsened significantly in CIN + PAG rats (p < 0.05) but improved in CIN + PAG + STS rats, with further improvement in CIN + STS rats to levels comparable to HC rats. Mechanistically, STS increased renal and plasma levels of H2S, arginine, cAMP, nitric oxide (NO) and cGMP as well as SIRT3 and PGC-1α. We have shown for the first time that STS provides chemoprotection against CIN by activating renal arginine/cAMP and NO/cGMP signaling pathways and their downstream mechanisms through increased renal H2S production.

Titin gene mutations enhance radiotherapy efficacy via modulation of tumour immune microenvironment in rectum adenocarcinoma

OBJECTIVE

This study investigates the impact of Titin (TTN) gene mutations on radiotherapy sensitivity in rectum adenocarcinoma (READ) by examining changes in the tumour immune microenvironment.

METHODS

Data on gene expression and mutations in READ were obtained from The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases. Bioinformatics analysis explored the correlation between TTN mutations and immune cell infiltration. In vitro, lentiviral vectors were used to assess TTN mutations' effects on ANKRD1 expression in two READ cell lines. ANKRD1 was overexpressed, and clonogenic assays evaluated radiotherapy sensitivity. Flow cytometry, immunofluorescence, and comet assays examined mutations' impact on cell cycle, apoptosis, and DNA damage response (DDR). An in vivo mouse model and formalin-fixed paraffin-embedded samples from locally advanced rectal cancer (LARC) patients before and after radiotherapy were analyzed, followed by prognostic evaluation.

RESULTS

Bioinformatics revealed that TTN mutations increase radiation sensitivity in LARC by slowing cell proliferation, promoting apoptosis, and reducing DDR. TTN mutations also inhibit ANKRD1 expression via JUN disruption and enhance CD4/CD8 T-cell infiltration, improving anti-tumour immunity and outcomes. Observations from the clinical study showed a substantial decline in ANKRD1 expression levels alongside a notable surge in the counts of CD4+ and CD8+ T cells after undergoing radiotherapy. Patients with TTN mutations, low ANKRD1 expression, and high densities of CD4+ and CD8+ T cells had longer 3-year disease-free survival in READ.

CONCLUSION

Our findings reveal that TTN mutations can serve as biomarkers for enhanced radiotherapy sensitivity in READ. By altering the tumour's immune microenvironment, these mutations may provide a novel target for personalized radiotherapy strategies, potentially improving therapeutic outcomes in patients with READ.

HIGHLIGHTS

The association between TTN mutations and tumour mutation burden, as well as immune cell infiltration in READ, is examined. TTN mutations enhance the radiation sensitivity of READ cells and weaken DNA damage repair in response to radiation. TTN mutations increase the radiation sensitivity of READ cells by inhibiting ANKRD1. The infiltration of CD8+ and CD4+ T cells induced by TTN mutations is essential for anti-tumour immunity. TTN mutations serve as a biomarker for the pathological response to preoperative radiotherapy in READ.

Protective Effect of Memantine on Cisplatin-Induced Ototoxicity: An In Vitro Study

HYPOTHESIS

Memantine, an N -methyl- d -aspartate receptor antagonist, is widely used to treat Alzheimer's disease and has been found to have potential neuroprotective effects. In this study, we evaluated the protective effects of memantine against cisplatin-induced ototoxicity.

BACKGROUND

Cisplatin is a widely used anticancer drug for various cancers; however, its use is limited by its side effects, including ototoxicity. Several drugs have been developed to reduce cisplatin toxicity. In this study, we treated cisplatin-damaged cochlear hair cells with memantine and evaluated its protective effects.

METHOD

House Ear Institute Organ of Corti 1 (HEI-OC1) cells and cochlear explants were treated with cisplatin or memantine. Cell viability, apoptotic patterns, reactive oxygen species (ROS) production, Bcl-2/caspase-3 activity, and cell numbers were measured to evaluate the anti-apoptotic and antioxidative effects of memantine.

RESULT

Memantine treatment significantly improved cell viability and reduced cisplatin-induced apoptosis in auditory cells. Bcl-2/caspase-3 activity was also significantly increased, suggesting anti-apoptotic effects against cisplatin-induced ototoxicity.

CONCLUSION

Our results suggest that memantine protects against cisplatin-induced ototoxicity in vitro, providing a potential new strategy for preventing hearing loss in patients undergoing cisplatin chemotherapy.

The Role of MicroRNA in the Pathogenesis of Acute Kidney Injury

Acute kidney injury (AKI) describes a condition associated with elevated serum creatinine levels and decreased glomerular filtration rate. AKI can develop as a result of sepsis, the nephrotoxic properties of several drugs, and ischemia/reperfusion injury. Renal damage can be associated with metabolic acidosis, fluid overload, and ionic disorders. As the molecular background of the pathogenesis of AKI is insufficiently understood, more studies are needed to identify the key signaling pathways and molecules involved in the progression of AKI. Consequently, future treatment methods may be able to restore organ function more rapidly and prevent progression to chronic kidney disease. MicroRNAs (miRNAs) are small molecules that belong to the non-coding RNA family. Recently, numerous studies have demonstrated the altered expression profile of miRNAs in various diseases, including inflammatory and neoplastic conditions. As miRNAs are major regulators of gene expression, their dysregulation is associated with impaired homeostasis and cellular behavior. The aim of this article is to discuss current evidence on the involvement of miRNAs in the pathogenesis of AKI.

Transcriptional activation of PINK1 by MyoD1 mediates mitochondrial homeostasis to induce renal calcification in pediatric nephrolithiasis

This study aims to uncover the molecular mechanisms underlying pediatric kidney stone formation induced by renal calcium deposition by utilizing high-throughput sequencing data to reveal the regulation of PINK1 by MyoD1. We performed transcriptome sequencing on peripheral blood samples from healthy children and children with kidney stones to obtain differentially expressed genes (DEGs). Genes related to mitochondrial oxidative stress were obtained from the Genecards website and intersected with DEGs to obtain candidate target genes. Additionally, we conducted protein-protein interaction (PPI) analysis using the STRING database to identify core genes involved in pediatric kidney stone disease (KSD) and predicted their transcription factors using the hTFtarget database. We assessed the impact of MyoD1 on the activity of the PINK1 promoter using dual-luciferase reporter assays and investigated the enrichment of MyoD1 on the PINK1 promoter through chromatin immunoprecipitation (ChIP) experiments. To validate our hypothesis, we selected HK-2 cells and established an in vitro kidney stone model induced by calcium oxalate monohydrate (COM). We evaluated the expression levels of various genes, cell viability, volume of adherent crystals in each group, as well as mitochondrial oxidative stress in cells by measuring mitochondrial membrane potential (Δψm), superoxide dismutase (SOD) activity, reactive oxygen species (ROS), and malondialdehyde (MDA) content. Mitochondrial autophagy was assessed using mtDNA fluorescence staining and Western blot analysis of PINK1-related proteins. Apoptosis-related proteins were evaluated using Western blot analysis, and cell apoptosis was measured using flow cytometry. Furthermore, we developed a rat model of KSD and assessed the expression levels of various genes, as well as the pathologic changes in rat renal tissues using H&E and von Kossa staining, transmission electron microscopy (TEM), and the expression of creatinine, blood urea nitrogen, neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecule-1 (KIM-1) to evaluate the mitochondrial oxidative stress in vivo (through measurement of Δψm, SOD activity, ROS, and MDA content). Mitochondrial autophagy was evaluated by Western blot analysis of PINK1-associated proteins. Apoptosis-related proteins were detected using Western blot analysis, and cellular apoptosis was examined using cell flow cytometry and TUNEL staining. Bioinformatics analysis revealed that the PINK1 gene is upregulated and vital in pediatric kidney stone patients. Our in vitro and in vivo experiments demonstrated that silencing PINK1 could inhibit kidney stone formation by suppressing mitochondrial oxidative stress both in vitro and in vivo. We identified MyoD1 as an upstream transcription factor of PINK1 that contributes to the occurrence of pediatric kidney stones through the activation of PINK1. Our in vivo and in vitro experiments collectively confirmed that silencing MyoD1 could inhibit mitochondrial oxidative stress, mitochondrial autophagy, and cellular apoptosis in a rat model of kidney stones by downregulating PINK1 expression, consequently suppressing the formation of kidney stones. In this study, we discovered that MyoD1 may promote kidney stone formation and development in pediatric patients by transcriptionally activating PINK1 to induce mitochondrial oxidative stress.

NOX4-mediated astrocyte ferroptosis in Alzheimer's disease

This study investigates NADPH oxidase 4 (NOX4) involvement in iron-mediated astrocyte cell death in Alzheimer's Disease (AD) using single-cell sequencing data and transcriptomes. We analyzed AD single-cell RNA sequencing data, identified astrocyte marker genes, and explored biological processes in astrocytes. We integrated AD-related chip data with ferroptosis-related genes, highlighting NOX4. We validated NOX4's role in ferroptosis and AD in vitro and in vivo. Astrocyte marker genes were enriched in AD, emphasizing their role. NOX4 emerged as a crucial player in astrocytic ferroptosis in AD. Silencing NOX4 mitigated ferroptosis, improved cognition, reduced Aβ and p-Tau levels, and alleviated mitochondrial abnormalities. NOX4 promotes astrocytic ferroptosis, underscoring its significance in AD progression.

Novel insights into STIM1's role in store-operated calcium entry and its implications for T-cell mediated inflammation in trigeminal neuralgia

This investigation aims to elucidate the novel role of Stromal Interaction Molecule 1 (STIM1) in modulating store-operated calcium entry (SOCE) and its subsequent impact on inflammatory cytokine release in T lymphocytes, thereby advancing our understanding of trigeminal neuralgia (TN) pathogenesis. Employing the Gene Expression Omnibus (GEO) database, we extracted microarray data pertinent to TN to identify differentially expressed genes (DEGs). A subsequent comparison with SOCE-related genes from the Genecards database helped pinpoint potential target genes. The STRING database facilitated protein-protein interaction (PPI) analysis to spotlight STIM1 as a gene of interest in TN. Through histological staining, transmission electron microscopy (TEM), and behavioral assessments, we probed STIM1's pathological effects on TN in rat models. Additionally, we examined STIM1's influence on the SOCE pathway in trigeminal ganglion cells using techniques like calcium content measurement, patch clamp electrophysiology, and STIM1- ORAI1 co-localization studies. Changes in the expression of inflammatory markers (TNF-α, IL-1β, IL-6) in T cells were quantified using Western blot (WB) and enzyme-linked immunosorbent assay (ELISA) in vitro, while immunohistochemistry and flow cytometry were applied in vivo to assess these cytokines and T cell count alterations. Our bioinformatic approach highlighted STIM1's significant overexpression in TN patients, underscoring its pivotal role in TN's etiology and progression. Experimental findings from both in vitro and in vivo studies corroborated STIM1's regulatory influence on the SOCE pathway. Furthermore, STIM1 was shown to mediate SOCE-induced inflammatory cytokine release in T lymphocytes, a critical factor in TN development. Supportive evidence from histological, ultrastructural, and behavioral analyses reinforced the link between STIM1-mediated SOCE and T lymphocyte-driven inflammation in TN pathogenesis. This study presents novel evidence that STIM1 is a key regulator of SOCE and inflammatory cytokine release in T lymphocytes, contributing significantly to the pathogenesis of trigeminal neuralgia. Our findings not only deepen the understanding of TN's molecular underpinnings but also potentially open new avenues for targeted therapeutic strategies.

PDCD4-induced oxidative stress through FGR/NF-κB axis in rectal cancer radiotherapy-induced AKI

This study aimed to investigate the molecular mechanism of the effect of PDCD4 on radiotherapy-induced acute kidney injury (AKI) in rectal cancer through the regulation of FGR/NF-κB signaling. Differentially expressed genes were identified using Gene Expression Omnibus (GEO) datasets (GSE90627 for rectal cancer and GSE145085 for AKI) and R software. The human renal tubular epithelial cell line, HK-2, was used to establish an in vitro model of radiotherapy-induced AKI. RT-qPCR and western blotting were used to detect gene and protein expression levels, respectively. Cell proliferation and apoptosis were assessed using the CCK-8 assay and flow cytometry, respectively. The malondialdehyde and superoxide dismutase levels in the cell culture supernatants were determined. Additionally, an in vivo AKI model was established using BALB/c mice, and kidney tissue morphology, expression of the renal injury molecule KIM-1, apoptosis of renal tubular cells, and TAS and TOS in serum were evaluated. Bioinformatics analysis revealed the upregulated expression of PDCD4 in AKI. In vitro experiments demonstrated that PDCD4 induced apoptosis in renal tubular cells by promoting FGR expression, which activated the NF-κB signaling pathway and triggered an oxidative stress response. In vivo animal experiments confirmed that PDCD4 promoted oxidative stress response and radiotherapy-induced AKI through the activation of the FGR/NF-κB signaling pathway. Silencing PDCD4 attenuated radiotherapy-induced AKI. Our findings suggest that PDCD4 may induce radiotherapy-induced AKI in rectal cancer by promoting FGR expression, activating the NF-κB signaling pathway, and triggering an oxidative stress response.

Antitumor activity and targeting p53-PUMA mRNA expression by 5-flurouracil PLGA-lipid polymeric nanoparticles in mouse mammary carcinomas: comparison to free 5-flurouracil

Polymeric poly (lactic-co-glycolic acid) (PLGA)-lipid hybrid nanoparticles (PNPs)-based therapy are powerful carriers for various therapeutic agents. This study was conducted to evaluate the chemotherapeutic potential of free 5-flurouracil (5FU) and synthetized 5FU-PNPs and impact on p53-dependent apoptosis in mammary carcinomas (MCs) grown in mice. Breast cancer cells were injected in Swiss albino female mice and 2 bilateral masses of MC were confirmed after one week. Mice were distributed to five experimental groups; Group 1: MC control group. Groups 2 and 3: MC + free 5FU [5 or 10 mg per kg] groups. Groups 4 and 5: synthetized MC+ 5FU-PNPs [5 or 10 mg per kg] groups. Medications were administered orally, twice weekly for 3 weeks. Then, tumors were dissected, and sections were stained with hematoxylin-eosin (HE) while the other MC was used for measuring of cell death and inflammatory markers. Treatment with 5FU-PNPs suppressed the MC masses and pathologic scores based on HE-staining. Similarly, greater proapoptotic activity was recorded in 5FU-PNPs groups compared to free 5FU groups as shown by significant upregulation in tumoral p53 immunostaining. The current results encourage the utility of PNPs for improving the antitumor effect of 5FU. The chemotherapeutic potential was mediated through enhancement of tumoral p53-mediated p53 up-regulated modulator of apoptosis (PUMA) genes. Additional studies are warranted for testing the antitumor activity of this preparation in other mouse models of breast cancer.

Platinum iodido drugs show potential anti-tumor activity, affecting cancer cell metabolism and inducing ROS and senescence in gastrointestinal cancer cells

Cisplatin-based chemotherapy has associated clinical disadvantages, such as high toxicity and resistance. Thus, the development of new antitumor metallodrugs able to overcome different clinical barriers is a public healthcare priority. Here, we studied the mechanism of action of the isomers trans and cis-[PtI2(isopropylamine)2] (I5 and I6, respectively) against gastrointestinal cancer cells. We demonstrate that I5 and I6 modulate mitochondrial metabolism, decreasing OXPHOS activity and negatively affecting ATP-linked oxygen consumption rate. Consequently, I5 and I6 generated Reactive Oxygen Species (ROS), provoking oxidative damage and eventually the induction of senescence. Thus, herein we propose a loop with three interconnected processes modulated by these iodido agents: (i) mitochondrial dysfunction and metabolic disruptions; (ii) ROS generation and oxidative damage; and (iii) cellular senescence. Functionally, I5 reduces cancer cell clonogenicity and tumor growth in a pancreatic xenograft model without systemic toxicity, highlighting a potential anticancer complex that warrants additional pre-clinical studies.

Transcriptionally activates CCL28 expression to inhibit M2 polarization of macrophages and prevent immune escape in colorectal cancer cells

OBJECTIVE

This study aimed to investigate the potential molecular mechanism of SPDEF in immune evasion of colorectal cancer (CRC) and examine its impact on macrophage M2 polarization using the TCGA and GEO databases.

METHODS

By combining TCGA and GEO databases, differential gene expression between CRC samples and standard tissue samples was analyzed to screen for immune-related genes (IRGs) associated with the prognosis of CRC patients. A predictive risk model was constructed based on 18 key IRGs, which were then validated using the GEO dataset. The relationship between transcription factors and IRGs was further explored to investigate their regulatory network in CRC. In vivo and in vitro experiments were carried out to validate these regulatory relationships and explore the function of SPDEF and CCL28 in CRC.

RESULTS

Twelve key IRGs associated with clinical and pathological characteristics of CRC patients were identified. Among them, CCL28 significantly impacted macrophage infiltration in CRC cells and may be a critical factor in immune evasion. In both in vitro and in vivo experiments, overexpression of SPDEF upregulated CCL28 expression, thereby suppressing M2 polarization of macrophages and inhibiting CRC cell proliferation and tumor growth. Notably, interference with CCL28 could reverse the effect of SPDEF overexpression.

CONCLUSION

SPDEF can suppress immune evasion of CRC cells by activating CCL28, which is achieved through the modulation of M2 polarization of macrophages. This provides a new research direction and potential therapeutic target for immunotherapy in CRC.

Limonin ameliorates cisplatin-induced acute liver injury by inhibiting 11β-hydroxysteroid dehydrogenase type 1

BACKGROUND

Acute liver injury (ALI) is a common side effect of cisplatin treatment in the clinic and can lead to liver failure if not treated promptly. Previous studies have revealed that Limonin, a critical bioactive substance in citrus fruits, can protect multiple organs from various medical conditions. However, whether Limonin could ameliorate cisplatin-induced ALI remains unclear.

METHODS

In vivo and in vitro models were induced by cisplatin in the present study. Non-targeted metabolomics was employed to analyze the metabolic changes in the liver after ALI. In addition, molecular docking was utilized to predict the potential targets of Limonin.

RESULTS

Limonin attenuated hepatic histopathological injury by reducing hepatocyte apoptosis, lipid peroxidation, and inflammation in cisplatin-challenged mice. Employing metabolomics, we revealed that Limonin mediated the balance of various disturbed metabolic pathways in the liver after cisplatin-induced ALI. Integrating public data mining, molecular docking studies, and in vitro experiments demonstrated that Limonin suppressed the expression and activity of its direct target, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), in the liver, thus reducing the production of corticosterone (CORT), a key metabolite promoted hepatocyte apoptosis.

CONCLUSIONS

Limonin improves the liver metabolic microenvironment by inhibiting 11β-HSD1 to protect against cisplatin-induced ALI.

Cytosine-phosphate-guanine oligodeoxynucleotides alleviate radiation-induced kidney injury in cervical cancer by inhibiting DNA damage and oxidative stress through blockade of PARP1/XRCC1 axis

BACKGROUND

Radiotherapy can cause kidney injury in patients with cervical cancer. This study aims to investigate the possible molecular mechanisms by which CpG-ODNs (Cytosine phosphate guanine-oligodeoxynucleotides) regulate the PARP1 (poly (ADP-ribose) polymerase 1)/XRCC1 (X-ray repair cross-complementing 1) signaling axis and its impact on radiation kidney injury (RKI) in cervical cancer radiotherapy.

METHODS

The GSE90627 dataset related to cervical cancer RKI was obtained from the Gene Expression Omnibus (GEO) database. Bioinformatics databases and R software packages were used to analyze the target genes regulated by CpG-ODNs. A mouse model of RKI was established by subjecting C57BL/6JNifdc mice to X-ray irradiation. Serum blood urea nitrogen (BUN) and creatinine levels were measured using an automated biochemical analyzer. Renal tissue morphology was observed through HE staining, while TUNEL staining was performed to detect apoptosis in renal tubular cells. ELISA was conducted to measure levels of oxidative stress-related factors in mouse serum and cell supernatant. An in vitro cell model of RKI was established using X-ray irradiation on HK-2 cells for mechanism validation. RT-qPCR was performed to determine the relative expression of PARP1 mRNA. Cell proliferation activity was assessed using the CCK-8 assay, and Caspase 3 activity was measured in HK-2 cells. Immunofluorescence was used to determine γH2AX expression.

RESULTS

Bioinformatics analysis revealed that the downstream targets regulated by CpG-ODNs in cervical cancer RKI were primarily PARP1 and XRCC1. CpG-ODNs may alleviate RKI by inhibiting DNA damage and oxidative stress levels. This resulted in significantly decreased levels of BUN and creatinine in RKI mice, as well as reduced renal tubular and glomerular damage, lower apoptosis rate, decreased DNA damage index (8-OHdG), and increased levels of antioxidant factors associated with oxidative stress (SOD, CAT, GSH, GPx). Among the CpG-ODNs, CpG-ODN2006 had a more pronounced effect. CpG-ODNs mediated the inhibition of PARP1, thereby suppressing DNA damage and oxidative stress response in vitro in HK-2 cells. Additionally, PARP1 promoted the formation of the PARP1 and XRCC1 complex by recruiting XRCC1, which in turn facilitated DNA damage and oxidative stress response in renal tubular cells. Overexpression of either PARP1 or XRCC1 reversed the inhibitory effects of CpG-ODN2006 on DNA damage and oxidative stress in the HK-2 cell model and RKI mouse model.

CONCLUSION

CpG-ODNs may mitigate cervical cancer RKI by blocking the activation of the PARP1/XRCC1 signaling axis, inhibiting DNA damage and oxidative stress response in renal tubule epithelial cells.

Pathological consequences of DNA damage in the kidney

DNA lesions that evade repair can lead to mutations that drive the development of cancer, and cellular responses to DNA damage can trigger senescence and cell death, which are associated with ageing. In the kidney, DNA damage has been implicated in both acute and chronic kidney injury, and in renal cell carcinoma. The susceptibility of the kidney to chemotherapeutic agents that damage DNA is well established, but an unexpected link between kidney ciliopathies and the DNA damage response has also been reported. In addition, human genetic deficiencies in DNA repair have highlighted DNA crosslinks, DNA breaks and transcription-blocking damage as lesions that are particularly toxic to the kidney. Genetic tools in mice, as well as advances in kidney organoid and single-cell RNA sequencing technologies, have provided important insights into how specific kidney cell types respond to DNA damage. The emerging view is that in the kidney, DNA damage affects the local microenvironment by triggering a damage response and cell proliferation to replenish injured cells, as well as inducing systemic responses aimed at reducing exposure to genotoxic stress. The pathological consequences of DNA damage are therefore key to the nephrotoxicity of DNA-damaging agents and the kidney phenotypes observed in human DNA repair-deficiency disorders.

Emerging role of tumor suppressor p53 in acute and chronic kidney diseases

p53 is a major regulator of cell cycle arrest, apoptosis, and senescence. While involvement of p53 in tumorigenesis is well established, recent studies implicate p53 in the initiation and progression of several renal diseases, which is the focus of this review. Ischemic-, aristolochic acid (AA) -, diabetic-, HIV-associated-, obstructive- and podocyte-induced nephropathies are accompanied by activation and/or elevated expression of p53. Studies utilizing chemical or renal-specific inhibition of p53 in mice confirm the pathogenic role of this transcription factor in acute kidney injury and chronic kidney disease. TGF-β1, NOX, ATM/ATR kinases, Cyclin G, HIPK, MDM2 and certain micro-RNAs are important determinants of renal p53 function in response to trauma. AA, cisplatin or TGF-β1-mediated ROS generation via NOXs promotes p53 phosphorylation and subsequent tubular dysfunction. p53-SMAD3 transcriptional cooperation downstream of TGF-β1 orchestrates induction of fibrotic factors, extracellular matrix accumulation and pathogenic renal cell communication. TGF-β1-induced micro-RNAs (such as mir-192) could facilitate p53 activation, leading to renal hypertrophy and matrix expansion in response to diabetic insults while AA-mediated mir-192 induction regulates p53 dependent epithelial G2/M arrest. The widespread involvement of p53 in tubular maladaptive repair, interstitial fibrosis, and podocyte injury indicate that p53 clinical targeting may hold promise as a novel therapeutic strategy for halting progression of certain acute and chronic renal diseases, which affect hundreds of million people worldwide.

Protective effect of luteolin against chemical and natural toxicants by targeting NF-κB pathway

Humans are continuously exposed to environmental, occupational, consumer and household products, food, and pharmaceutical substances. Luteolin, a flavone from the flavonoids family of compounds, is found in different fruits and vegetables. LUT is a strong anti-inflammatory (via inhibition of NF-κB, ERK1/2, MAPK, JNK, IL-6, IL-8, and TNF-α) and antioxidant agent (reducing ROS and enhancement of endogenous antioxidants). LUT can chelate transition metal ions responsible for ROS generation and consequently repress lipoxygenase. It has been proven that NF-κB, as a commom cellular pathway plays a considerable role in the progression of inflammatory process and stimulates the expression of genes encoding inducible pro-inflammatory enzymes (iNOS and COX-2) and cytokines including IL-1β, IL-6, and TNF-α. This review summarizes the available literature discussing LUT and its potential protective role against pharmaceuticals-, metals-, and environmental compounds-induced toxicities. Furthermore, the review explains the involved protective mechanisms, especially inhibition of the NF-κB pathway.

CD8+ T cell-derived IL-13 increases macrophage IL-10 to resolve neuropathic pain

Understanding the endogenous mechanisms regulating resolution of pain may identify novel targets for treatment of chronic pain. Resolution of chemotherapy-induced peripheral neuropathy (CIPN) after treatment completion depends on CD8⁺ T cells and on IL-10 produced by other cells. Using Rag2^–/– mice lacking T and B cells and adoptive transfer of Il13^–/– CD8⁺ T cells, we showed that CD8⁺ T cells producing IL-13 were required for resolution of CIPN. Intrathecal administration of anti–IL-13 delayed resolution of CIPN and reduced IL-10 production by dorsal root ganglion macrophages. Depleting local CD206⁺ macrophages also delayed resolution of CIPN. In vitro, TIM3⁺CD8⁺ T cells cultured with cisplatin, apoptotic cells, or phosphatidylserine liposomes produced IL-13, which induced IL-10 in macrophages. In vivo, resolution of CIPN was delayed by intrathecal administration of anti-TIM3. Resolution was also delayed in Rag2^–/– mice reconstituted with Havcr2 (TIM3)^–/– CD8⁺ T cells. Our data indicated that cell damage induced by cisplatin activated TIM3 on CD8⁺ T cells, leading to increased IL-13 production, which in turn induced macrophage IL-10 production and resolution of CIPN. Development of exogenous activators of the IL-13/IL-10 pain resolution pathway may provide a way to treat the underlying cause of chronic pain.

p53 in Proximal Tubules Mediates Chronic Kidney Problems after Cisplatin Treatment

Nephrotoxicity is a major side-effect of cisplatin in chemotherapy, which can occur acutely or progress into chronic kidney disease (CKD). The protein p53 plays an important role in acute kidney injury induced by cisplatin, but its involvement in CKD following cisplatin exposure is unclear. Here, we address this question by using experimental models of repeated low-dose cisplatin (RLDC) treatment. In mouse proximal tubular BUMPT cells, RLDC treatment induced p53 activation, apoptosis, and fibrotic changes, which were suppressed by pifithrin-α, a pharmacologic inhibitor of p53. In vivo, chronic kidney problems following RLDC treatment were ameliorated in proximal tubule-specific p53-knockout mice (PT-p53-KO mice). Compared with wild-type littermates, PT-p53-KO mice showed less renal damage (KIM-1 positive area: 0.97% vs. 2.5%), less tubular degeneration (LTL positive area: 15.97% vs. 10.54%), and increased proliferation (Ki67 positive area: 2.42% vs. 0.45%), resulting in better renal function after RLDC treatment. Together, these results indicate that p53 in proximal tubular cells contributes significantly to the development of chronic kidney problems following cisplatin chemotherapy.

Leonurine attenuates cisplatin nephrotoxicity by suppressing the NLRP3 inflammasome, mitochondrial dysfunction, and endoplasmic reticulum stress

PURPOSE

Cisplatin has been widely accepted as an effective chemotherapy drug with various side effects, including nephrotoxicity. The mechanisms of cisplatin-induced acute kidney injury (AKI) are complex, and there are limited renoprotective approaches. Leonurine is the main active compound of a Chinese herb and has recently been reported to have a protective effect on the kidneys. This study aimed to verify the renoprotective effect of leonurine in attenuating cisplatin-induced AKI and explore the potential associated mechanisms.

METHODS

C57BL/6 mice were divided into four groups (Sham, Cisplatin, Leonurine, and Cisplatin + Leonurine). Mice in the leonurine-treated groups were pretreated with a daily intraperitoneal injection of 25 mg/kg leonurine. AKI was induced by injecting cisplatin once intraperitoneally at 20 mg/kg body weight. Mice were killed on day 5. Kidney injury was assessed using a serum biochemical and histological assay. Apoptosis was evaluated using a terminal deoxyribonucleotide transferase-mediated dUTP nick-end labeling (TUNEL) staining assay and Western blot. Antioxidant enzymes were detected using commercial kits. The improvement in inflammasome activation, mitochondrial dysfunction, and endoplasmic reticulum stress (ERS) were assessed by polymerase chain reaction (PCR) and Western blot, respectively.

RESULTS

Leonurine treatment improved kidney function by preventing renal tubular injury and apoptosis. Expression of nucleotide-binding leucine-rich repeat and pyrin domain containing protein 3 (NLRP3) inflammasome components and inflammatory cytokines, mitochondrial dysfunction, and ERS were all alleviated by leonurine.

CONCLUSION

The results indicate that leonurine plays a protective role in cisplatin-induced AKI and may represent an effective multi-targeted intervention strategy.

Inhibition of HDAC3 protects against kidney cold storage/transplantation injury and allograft dysfunction

Cold storage/rewarming is an inevitable process for kidney transplantation from deceased donors, which correlates closely with renal ischemia-reperfusion injury (IRI) and the occurrence of delayed graft function. Histone deacetylases (HDAC) are important epigenetic regulators, but their involvement in cold storage/rewarming injury in kidney transplantation is unclear. In the present study, we showed a dynamic change of HDAC3 in a mouse model of kidney cold storage followed by transplantation. We then demonstrated that the selective HDAC3 inhibitor RGFP966 could reduce acute tubular injury and cell death after prolonged cold storage with transplantation. RGFP966 also improved renal function, kidney repair and tubular integrity when the transplanted kidney became the sole life-supporting graft in the recipient mouse. In vitro, cold storage of proximal tubular cells followed by rewarming induced remarkable cell death, which was suppressed by RGFP966 or knockdown of HDAC3 with shRNA. Inhibition of HDAC3 decreased the mitochondrial pathway of apoptosis and preserved mitochondrial membrane potential. Collectively, HDAC3 plays a pathogenic role in cold storage/rewarming injury in kidney transplantation, and its inhibition may be a therapeutic option.

Panduratin A Derivative Protects against Cisplatin-Induced Apoptosis of Renal Proximal Tubular Cells and Kidney Injury in Mice

BACKGROUND

Panduratin A is a bioactive cyclohexanyl chalcone exhibiting several pharmacological activities, such as anti-inflammatory, anti-oxidative, and anti-cancer activities. Recently, the nephroprotective effect of panduratin A in cisplatin (CDDP) treatment was revealed. The present study examined the potential of certain compounds derived from panduratin A to protect against CDDP-induced nephrotoxicity.

METHODS

Three derivatives of panduratin A (DD-217, DD-218, and DD-219) were semi-synthesized from panduratin A. We investigated the effects and corresponding mechanisms of the derivatives of panduratin A for preventing nephrotoxicity of CDDP in both immortalized human renal proximal tubular cells (RPTEC/TERT1 cells) and mice.

RESULTS

Treating the cell with 10 µM panduratin A significantly reduced the viability of RPTEC/TERT1 cells compared to control (panduratin A: 72% ± 4.85%). Interestingly, DD-217, DD-218, and DD-219 at the same concentration did not significantly affect cell viability (92% ± 8.44%, 90% ± 7.50%, and 87 ± 5.2%, respectively). Among those derivatives, DD-218 exhibited the most protective effect against CDDP-induced renal proximal tubular cell apoptosis (control: 57% ± 1.23%; DD-218: 19% ± 10.14%; DD-219: 33% ± 14.06%). The cytoprotective effect of DD-218 was mediated via decreases in CDDP-induced mitochondria dysfunction, intracellular reactive oxygen species (ROS) generation, activation of ERK1/2, and cleaved-caspase 3 and 7. In addition, DD-218 attenuated CDDP-induced nephrotoxicity by a decrease in renal injury and improved in renal dysfunction in C57BL/6 mice. Importantly, DD-218 did not attenuate the anti-cancer efficacy of CDDP in non-small-cell lung cancer cells or colon cancer cells.

CONCLUSIONS

This finding suggests that DD-218, a derivative of panduratin A, holds promise as an adjuvant therapy in patients receiving CDDP.

Proximal Tubule p53 in Cold Storage/Transplantation-Associated Kidney Injury and Renal Graft Dysfunction

Kidney injury associated with cold storage/transplantation is a primary factor for delayed graft function and poor outcome of renal transplants. p53 contributes to both ischemic and nephrotoxic kidney injury, but its involvement in kidney cold storage/transplantation is unclear. Here, we report that p53 in kidney proximal tubules plays a critical role in cold storage/transplantation kidney injury and inhibition of p53 can effectively improve the histology and function of transplanted kidneys. In a mouse kidney cold storage/transplantation model, we detected p53 accumulation in proximal tubules in a cold storage time-dependent manner, which correlated with tubular injury and cell death. Pifithrin-α, a pharmacologic p53 inhibitor, could reduce acute tubular injury, apoptosis and inflammation at 24 h after cold storage/transplantation. Similar effects were shown by the ablation of p53 from proximal tubule cells. Notably, pifithrin-α also ameliorated kidney injury and improved the function of transplanted kidneys in 6 days when it became the sole life-supporting kidney in recipient mice. in vitro, cold storage followed by rewarming induced cell death in cultured proximal tubule cells, which was accompanied by p53 activation and suppressed by pifithrin-α and dominant-negative p53. Together, these results support a pathogenic role of p53 in cold storage/transplantation kidney injury and demonstrate the therapeutic potential of p53 inhibitors.

Protective Effect of Pyxinol, One Active Ingredient of Lichenes on Cisplatin-Induced Nephrotoxicity via Ameliorating DNA Damage Response

Background: Cisplatin is a valuable chemotherapeutic agent against malignant tumors. However, the clinical use of cisplatin is limited by its side effects such as renal injury. Pyxinol is an active constituent of Lichenes and its effects on cisplatin-induced nephrotoxicity is currently unknown. This study aims to examine the potential protective effects of pyxinol on cisplatin-induced renal injury and explore the underlying mechanisms.

Methods:In vivo rat model of cisplatin-induced nephrotoxicity was induced by intraperitoneal (i.p) administration of cisplatin. The blood urea nitrogen and creatinine levels were measured and renal histological analysis was conducted to evaluate the renal function; The TUNEL staining, western blotting and real-time PCR assays were conducted to examine related molecular changes. Finally, the in vivo anti-tumor efficacy was examined in the xenograft tumor model using nude mice.

Results: Pretreatment with pyxinol attenuated cisplatin-induced increase in blood urea nitrogen, creatinine and urinary protein excretion and the magnitude of injury in the renal tubules. Pyxinol ameliorated the activation of p53 via attenuating the DNA damage response, which then attenuated the tubular cell apoptosis. Finally, pyxinol could potentiate the in vivo anti-tumor efficacy of cisplatin against the xenograft tumor of cervical cancer cells in nude mice.

Conclusions: Combining pyxinol with cisplatin could alleviate cisplatin-induced renal injury without decreasing its therapeutic efficacy, which might represent a beneficial adjunct therapy for cisplatin-based chemotherapeutic regimens in the clinic.

In Vitro Nephrotoxicity Studies of Established and Experimental Platinum-Based Compounds

Cisplatin is one of the most commonly used drugs for the treatment of various solid cancers. However, its efficacy is restricted by severe side effects, especially dose-limiting nephrotoxicity. New platinum-based compounds are designed to overcome this limitation. Previous investigations showed that the platinum(IV)–nitroxyl complex PN149 is highly cytotoxic in various tumor cell lines. In the present study, investigations with PN149 were extended to normal human kidney tubule epithelia. Coincident with higher intracellular platinum accumulation, the cytotoxicity of PN149 in the proximal tubule epithelial cell line ciPTEC was more pronounced compared to the established platinum chemotherapeutics cisplatin, carboplatin and oxaliplatin. Quantitative gene expression profiling revealed the induction of ROS-inducible and anti-oxidative genes, suggesting an oxidative stress response by PN149. However, in contrast to cisplatin, no pro-inflammatory response was observed. Genes coding for distinct DNA damage response factors and genes related to apoptosis were up-regulated, indicating the activation of the DNA damage response system and induction of the apoptotic cascade by PN149. Altogether, a comparable transcriptional response was observed for PN149 and the platinum chemotherapeutics. However, the lack of inflammatory activity, which is a possible cause contributing to toxicity in human renal proximal tubule epithelia, might indicate the reduced nephrotoxic potential of PN149.

Platinum drugs and taxanes: can we overcome resistance?

Cancer therapy is aimed at the elimination of tumor cells and acts via the cessation of cell proliferation and induction of cell death. Many research publications discussing the mechanisms of anticancer drugs use the terms "cell death" and "apoptosis" interchangeably, given that apoptotic pathways are the most common components of the action of targeted and cytotoxic compounds. However, there is sound evidence suggesting that other mechanisms of drug-induced cell death, such as necroptosis, ferroptosis, autophagy, etc. may significantly contribute to the fate of cancer cells. Molecular cross-talks between apoptotic and nonapoptotic death pathways underlie the successes and the failures of therapeutic interventions. Here we discuss the nuances of the antitumor action of two groups of the widely used anticancer drugs, i.e., platinum salts and taxane derivatives. The available data suggest that intelligent interference with the choice of cell death pathways may open novel opportunities for cancer treatment.

NAM protects against cisplatin-induced acute kidney injury by suppressing the PARP1/p53 pathway

Cisplatin is a commonly used anti-cancer drug, but it induces nephrotoxicity. As a water-soluble vitamin B family member, nicotinamide (NAM) was recently demonstrated to have beneficial effects for renal injury, but its underlying mechanism remains largely unclear. Here, we suggest that NAM may exert protective effects against cisplatin-induced acute kidney injury (AKI) mainly via suppressing the poly ADP-ribose polymerase 1 (PARP1)/p53 pathway. In our experiment, NAM protected against cisplatin-induced apoptosis both in cultured renal proximal tubular cells and AKI in mice. Mechanistically, NAM suppressed the expression and activation of p53, a known mediator of cisplatin-induced AKI. Upstream of p53, NAM attenuated the induction of γ-H2AX, a hallmark of DNA damage response. Interestingly, PARP1 was activated in cisplatin AKI and this activation was inhibited by NAM. Pharmacological inhibition of PARP1 with PJ34 significantly ameliorated p53 activation and cisplatin-induced cell death in RPTCs and AKI in mice. Thus, NAM may protect against cisplatin-induced AKI by suppressing the PARP1/p53 pathway.

Environmentally relevant concentration of sulfamethoxazole-induced oxidative stress-cascaded damages in the intestine of grass carp and the therapeutic application of exogenous lycopene

Due to the unreasonable use and discharge of the aquaculture industry, over standard of the antibiotics has been frequent in different types of water environments, causing adverse effects on aquatic organisms. Lycopene (LYC) is an esculent carotenoid, which is considered to be a strong antioxidant. This study was designed to explore the therapeutic effect of LYC on antibiotic (sulfamethoxazole (SMZ)) induced intestinal injury in grass carp Ctenopharyngodon idella. The 120 carps (the control, LYC, SMZ, and co-administration groups) were treated for 30 days. We found that treatment with LYC significantly suppressed SMZ-induced intestinal epithelial cell damage and tight junction protein destruction through histopathological observation, transmission electron microscopy and detection of related genes (Claudin-1/3/4, Occludin and zonula occludens (ZO)-1/2). Furthermore, LYC mitigated SMZ-induced dysregulation of oxidative stress markers, including elevated malondialdehyde (MDA) levels, and consumed super oxide dimutese (SOD), catalase (CAT) activities and glutathione (GSH) content. In the same treatment, LYC reduced inflammation and apoptosis by a detectable change in pro-inflammatory factors (tumor necrosis factor-alpha (TNF-β), interleukin (IL)-1β, IL-6 and IL-8), anti-inflammatory factors (transforming growth factor-beta (TGF-β) and IL-10) and pro-apoptosis related genes (p53, p53 upregulated modulator of apoptosis (PUMA), Bax/Bcl-2 ratio, caspase-3/9). In addition, activation of autophagy (as indicated by increased autophagy-related genes through AMPK/ATK/MTOR signaling pathway) under the stress of SMZ was also dropped back to the original levels by LYC co-administration. Collectively, our findings identified that LYC can serve as a protectant agent against SMZ-induced intestinal injury.

Regulated cell death in cisplatin-induced AKI: relevance of myo-inositol metabolism

Regulated cell death (RCD), distinct from accidental cell death, refers to a process of well-controlled programmed cell death with well-defined pathological mechanisms. In the past few decades, various terms for RCDs were coined, and some of them have been implicated in the pathogenesis of various types of acute kidney injury (AKI). Cisplatin is widely used as a chemotherapeutic drug for a broad spectrum of cancers, but its usage was hampered because of being highly nephrotoxic. Cisplatin-induced AKI is commonly seen clinically, and it also serves as a well-established prototypic model for laboratory investigations relevant to acute nephropathy affecting especially the tubular compartment. Literature reports over a period of three decades have indicated that there are multiple types of RCDs, including apoptosis, necroptosis, pyroptosis, ferroptosis, and mitochondrial permeability transition-mediated necrosis, and some of them are pertinent to the pathogenesis of cisplatin-induced AKI. Interestingly, myo-inositol metabolism, a vital biological process that is largely restricted to the kidney, seems to be relevant to the pathogenesis of certain forms of RCDs. A comprehensive understanding of RCDs in cisplatin-induced AKI and their relevance to myo-inositol homeostasis may yield novel therapeutic targets for the amelioration of cisplatin-related nephropathy.

Mechanisms of Cisplatin-Induced Acute Kidney Injury: Pathological Mechanisms, Pharmacological Interventions, and Genetic Mitigations

Administration of the chemotherapeutic agent cisplatin leads to acute kidney injury (AKI). Cisplatin-induced AKI (CIAKI) has a complex pathophysiological map, which has been linked to cellular uptake and efflux, apoptosis, vascular injury, oxidative and endoplasmic reticulum stress, and inflammation. Despite research efforts, pharmaceutical interventions, and clinical trials spanning over several decades, a consistent and stable pharmacological treatment option to reduce AKI in patients receiving cisplatin remains unavailable. This has been predominately linked to the incomplete understanding of CIAKI pathophysiology and molecular mechanisms involved. Herein, we detail the extensively known pathophysiology of cisplatin-induced nephrotoxicity that manifests and the variety of pharmacological and genetic alteration studies that target them.

Compound C Protects Against Cisplatin-Induced Nephrotoxicity Through Pleiotropic Effects

AICAR (Acadesine/AICA riboside) as an activator of AMPK, can protect renal tubular cells from cisplatin induced apoptosis. But in our experiment, the dorsomorphin (compound C, an inhibitor of AMPK) also significantly reduced cisplatin induced renal tubular cells apoptosis. Accordingly, we tested whether compound C can protect cisplatin-induced nephrotoxicity and the specific mechanism. Here, we treated Boston University mouse proximal tubular cells (BUMPT-306) with cisplatin and/or different dosages of AICAR (Acadesine/AICA riboside) or compound C to confirm the effect of AICAR and compound C in vitro. The AMPK-siRNA treated cells to evaluate whether the protective effect of compound C was through inhibiting AMPK. Male C57BL/6 mice were used to verify the effect of compound C in vivo. Both compound C and AICAR can reduce renal tubular cells apoptosis in dose-dependent manners, and compound C decreased serum creatinine and renal tubular injury induced by cisplatin. Mechanistically, compound C inhibited P53, CHOP and p-IREα during cisplatin treatment. Our results demonstrated that compound C inhibited AMPK, but the renal protective effects of compound C were not through AMPK. Instead, compound C protected cisplatin nephrotoxicity by inhibiting P53 and endoplasmic reticulum (ER) stress. Therefore, compound C may protect against cisplatin-induced nephrotoxicity through pleiotropic effects.

HIF in Nephrotoxicity during Cisplatin Chemotherapy: Regulation, Function and Therapeutic Potential

Simple Summary

Cisplatin is a widely used chemotherapy drug, but its use and efficacy are limited by its nephrotoxicity. HIF has protective effects against kidney injury during cisplatin chemotherapy, but it may attenuate the anti-cancer effect of cisplatin. In this review, we describe the role and regulation of HIF in cisplatin-induced nephrotoxicity and highlight the therapeutic potential of targeting HIF in chemotherapy.

Abstract

Cisplatin is a highly effective, broad-spectrum chemotherapeutic drug, yet its clinical use and efficacy are limited by its side effects. Particularly, cancer patients receiving cisplatin chemotherapy have high incidence of kidney problems. Hypoxia-inducible factor (HIF) is the “master” transcription factor that is induced under hypoxia to trans-activate various genes for adaptation to the low oxygen condition. Numerous studies have reported that HIF activation protects against AKI and promotes kidney recovery in experimental models of cisplatin-induced acute kidney injury (AKI). In contrast, little is known about the effects of HIF on chronic kidney problems following cisplatin chemotherapy. Prolyl hydroxylase (PHD) inhibitors are potent HIF inducers that recently entered clinical use. By inducing HIF, PHD inhibitors may protect kidneys during cisplatin chemotherapy. However, HIF activation by PHD inhibitors may reduce the anti-cancer effect of cisplatin in tumors. Future studies should test PHD inhibitors in tumor-bearing animal models to verify their effects in kidneys and tumors.

Bromamine T (BAT) Exerts Stronger Anti-Cancer Properties than Taurine (Tau)

BACKGROUND

Taurine (Tau) ameliorates cancer pathogenesis. Researchers have focused on the functional properties of bromamine T (BAT), a stable active bromine molecule. Both N-bromotaurine (TauNHBr) and BAT exert potent anti-inflammatory properties, but the landscape remains obscure concerning the anti-cancer effect of BAT.

METHODS

We used Crystal Violet, colony formation, flow cytometry and Western blot experiments to evaluate the effect of BAT and Tau on the apoptosis and autophagy of cancer cells. Xenograft experiments were used to determine the in vivo cytotoxicity of either agent.

RESULTS

We demonstrated that both BAT and Tau inhibited the growth of human colon, breast, cervical and skin cancer cell lines. Among them, BAT exerted the greatest cytotoxic effect on both RKO and MDA-MB-468 cells. In particular, BAT increased the phosphorylation of c-Jun N-terminal kinases (JNK½), p38 mitogen-activated protein kinase (MAPK), and extracellular-signal-regulated kinases (ERK½), thereby inducing mitochondrial apoptosis and autophagy in RKO cells. In contrast, Tau exerted its cytotoxic effect by upregulating JNK½ forms, thus triggering mitochondrial apoptosis in RKO cells. Accordingly, colon cancer growth was impaired in vivo.

CONCLUSIONS

BAT and Tau exerted their anti-tumor properties through the induction of (i) mitochondrial apoptosis, (ii) the MAPK family, and iii) autophagy, providing novel anti-cancer therapeutic modalities.

Pioglitazone alleviates cisplatin nephrotoxicity by suppressing mitochondria-mediated apoptosis via SIRT1/p53 signalling

Pioglitazone (PIO) attenuates cisplatin nephrotoxicity whereas the underlying mechanism remains unknown. Apoptosis is associated with mitochondrial dysfunction and SIRT1 activation can decrease cell apoptosis in cisplatin nephrotoxicity. Therefore, we explored whether the protective effect of PIO in cisplatin nephrotoxicity is achieved by suppressing mitochondria‐mediated apoptosis through SIRT1/p53 signalling regulation. Cell viability, apoptosis, survival rate, renal pathology and function were examined. Moreover, we also analysed the expression of SIRT1, Acetyl‐p53, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), mitochondrial permeability transition pore (mPTP) opening, adenosine triphosphate (ATP) and apoptosis‐related protein in vivo and in vitro. Pioglitazone treatment significantly increased cell viability, promoted SIRT1‐p53 interaction, upregulated Bcl‐2 expression, activated SIRT1 and elevated mitochondrial ATP synthesis after cisplatin treatment. However, PIO decreased the generation of ROS, opening of mPTP, dissipation of MMP and translocation of cytochrome c after cisplatin treatment. Pioglitazone also reduced the activation of caspase‐3 and caspase‐9, lowered the ratio of Bax/Bcl‐2, attenuated kidney pathological damage and dysfunction, down‐regulated the expression of Acetyl‐p53, PUMA‐α and Bax and abated cell apoptosis after cisplatin treatment. The SIRT1 inhibitor, EX527, clearly reversed the protective effects of PIO. These results implied PIO attenuated cisplatin nephrotoxicity by suppressing mitochondria‐mediated apoptosis through regulating SIRT1/p53 signalling.

Vernonia cinerea regenerates tubular epithelial cells in cisplatin induced nephrotoxicity in cancer bearing mice without affecting antitumor activity

Background

Traditional Siddha Medicine advises using metal-based formulations to treat cancers. In the case of any toxicities during the therapy, Siddha physicians use Vernonia cinerea (VC) whole plant kashayam (crude aqueous extract-CAE) to reverse the toxic effects.

Aim

To evaluate the nephroprotective activity of CAE and its fractions in cisplatin-induced nephrotoxicity and to assess whether they compromise the anticancer efficacy of cisplatin.

Materials and methods

Cisplatin-induced renal damage was induced in Ehrlich Ascites Carcinoma (EAC) bearing mice during mild phase of tumor growth. CAE and its butanol (BF) and aqueous (AF) fractions were administered orally from the 5th day for five days. Nephroprotective potential (serum urea, creatinine, renal histology) and effect of VC on cisplatin anticancer efficacy (tumor volume, viable tumor cells, percentage increase in life span (% ILS)) were calculated.

Result

CAE and its fractions significantly reversed the cisplatin-induced renal damage. CAE and BF treated animals showed regeneration of 50%–75% of proximal tubular cells. Compared to EAC control mice, the % ILS of the cisplatin-treated group was 244% and it was further extended to 379% after CAE administration. The % ILS in the CAE treated group was 1.6 times higher than the cisplatin alone treated group. GC-MS study showed the presence of astaxanthin and betulin.

Conclusion

CAE of VC reverses cisplatin-induced kidney damage as well as regenerates proximal tubular epithelial cells, without compromising the anticancer effect of cisplatin. When CAE was further fractionated, the nephroprotective activity was retained, but the beneficial anticancer effect of cisplatin was compromised.

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Vernonia cinerea (VC) significantly reverses cisplatin-induced kidney damage.

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VC regenerates the damaged proximal tubular epithelial cells.

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VC did not compromise the anticancer beneficial effect of cisplatin.

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Fractionation of VC lead to compromising of cisplatin anticancer effect.

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Astaxanthin and betulin present in VC could be resposible for its nephroprotective effect.

Ganoderma lucidum Prevents Cisplatin-Induced Nephrotoxicity through Inhibition of Epidermal Growth Factor Receptor Signaling and Autophagy-Mediated Apoptosis

Background

Cisplatin (cis-diaminedichloroplatinum, CDDP) is a broad-spectrum antineoplastic agent. However, CDDP has been blamed for its nephrotoxicity, which is the main dose-limiting adverse effect. Ganoderma lucidum (GL), a medicinal mushroom, has antioxidant and inflammatory activities. Therefore, this study is aimed at finding out the potential nephroprotection of GL against CDDP-induced nephrotoxicity in rats and the possible molecular mechanisms including the EGFR downstream signaling, apoptosis, and autophagy.

Methods

Rats were given GL (500 mg/kg) for 10 days and a single injection of CDDP (12 mg/kg, i.p).

Results

Nephrotoxicity was evidenced by a significant increase in renal indices and oxidative stress markers. Additionally, CDDP showed a plethora of inflammatory and apoptotic responses as evidenced by a profound increase of HMGB-1, NF-κB, and caspase-3 expressions, whereas administration of GL significantly improved all these indices as well as the histopathological insults. Renal expression of EGFR showed a similar trend after GL administration. Furthermore, activation of autophagy protein, LC3 II, was found to be involved in GL-mediated nephroprotection correlated with the downregulation of apoptotic signaling, caspase-3 and terminal deoxynucleotidyl transferase (TDT) renal expressions.

Conclusion

These results suggest that GL might have improved CDDP-induced nephrotoxicity through antioxidant, anti-inflammatory, and autophagy-mediated apoptosis mechanisms and that inhibition of EGFR signaling might be involved in nephroprotection.

Inhibition of p53 DNA binding by a small molecule protects mice from radiation toxicity

Transcription factors are attractive therapeutic targets that are considered non-druggable because they do not have binding sites for small drug-like ligands. We established a cell-free high-throughput screening assay to search for small molecule inhibitors of DNA binding by transcription factors. A screen was performed using p53 as a target, resulting in the identification of NSC194598 that inhibits p53 sequence-specific DNA binding in vitro (IC₅₀ = 180 nM) and in vivo. NSC194598 selectively inhibited DNA binding by p53 and homologs p63/p73, but did not affect E2F1, TCF1, and c-Myc. Treatment of cells with NSC194598 alone paradoxically led to p53 accumulation and modest increase of transcriptional output owing to disruption of the MDM2-negative feedback loop. When p53 was stabilized and activated by irradiation or chemotherapy drug treatment, NSC194598 inhibited p53 DNA binding and induction of target genes. A single dose of NSC194598 increased the survival of mice after irradiation. The results suggest DNA binding by p53 can be targeted using small molecules to reduce acute toxicity to normal tissues by radiation and chemotherapy.

Influence of Tumor Suppressor p53 Functioning on the Expression of Antioxidant System Genes under the Action of Cytotoxic Compounds

The effect of inhibition of the tumor suppressor p53 on the antioxidant system genes expression under the influence of cytotoxic compounds of the platinum group was studied. It was found that the action of platinum(II) and platinum(IV) complexes induced accumulation of p53 protein with a maximum in 12 h, which was confirmed by an increase in the expression of the P21 gene, the target gene of the p53 protein. It was shown that the action of platinum complexes activated the expression of catalase and superoxide dismutase 2 genes. Suppression of p53 protein functions with specific inhibitor α-piphitrin under the action of platinum complexes reduced the expression of catalase and superoxide dismutase 2 genes and the target gene P21, which attested to the p53-dependent regulation of these genes.

Renoprotective Effects of a New Free Radical Scavenger, XH-003, against Cisplatin-Induced Nephrotoxicity

Acute renal injury has an incidence of 25%–30% in patients with tumors who are treated with cisplatin and in patients for whom no specific drugs are available for treatment. Amifostine is the only FDA-approved chemoprotective drug; however, its clinical application is limited because of side effects. The small-molecule antioxidant XH-003, an acute radiation syndrome- (ARS-) protective drug independently developed in our laboratory, with 100% intellectual property rights, overcomes the side effects of amifostine but retains its high efficacy. In this study, XH-003 showed a chemoprotective effect similar to that of amifostine. A mechanistic study showed that XH-003 could significantly reduce cisplatin-induced increases in serum creatinine and urea nitrogen, increase the activity of antioxidant enzymes (SOD, CAT, and GSH-Px), reduce oxidative stress and tissue inflammation, and alleviate renal tissue damage by blocking the activity of the mitochondrial apoptosis pathway. Most importantly, XH-003 could reduce the accumulation of cisplatin in renal tissue by regulating the expression of proteins involved in cisplatin uptake and excretion, such as organic cation transporter 2 and MRP2. Moreover, in an in vivo xenotransplantation model, XH-003 did not interfere with the antitumor effect of cisplatin. These data provide strong evidence that the ARS-protective agent has a great potential for protecting against chemotherapy-induced toxicity. Thus, XH-003 can be considered in antitumor therapy.

Canagliflozin reduces cisplatin uptake and activates Akt to protect against cisplatin-induced nephrotoxicity

Cisplatin is a widely used chemotherapy drug with notorious nephrotoxicity. Na⁺-glucose cotransporter 2 inhibitors are a class of novel antidiabetic agents that may have other effects in the kidneys besides blood glucose control. In the present study, we demonstrated that canagliflozin significantly attenuates cisplatin-induced nephropathy in C57BL/6 mice and suppresses cisplatin induced renal proximal tubular cell apoptosis in vitro. The protective effect of canagliflozin was associated with inhibition of p53, p38 and JNK activation. Mechanistically, canagliflozin partially reduced cisplatin uptake by kidney tissues in mice and renal tubular cells in culture. In addition, canagliflozin enhanced the activation of Akt and inhibited the mitochondrial pathway of apoptosis during cisplatin treatment. The protective effect of canagliflozin was diminished by the phosphatidylinositol 3-kinase/Akt inhibitor LY294002. Notably, canagliflozin did not affect the chemotherapeutic efficacy of cisplatin in A549 and HCT116 cancer cell lines. These results suggest a new application of canagliflozin for renoprotection in cisplatin chemotherapy. Canagliflozin may protect kidneys by reducing cisplatin uptake and activating cell survival pathways.

Effect of memantine hydrochloride on cisplatin-induced neurobehavioral toxicity in mice

Cisplatin is an anticancer agent widely used in the treatment of malignant tumors. One of the major adverse effects of cisplatin is its neurotoxicity. Memantine, an uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, has been reported to have neuroprotective effects against neurological deficits. This study therefore investigated the possible protective role of memantine as an agent to minimize the neurobehavioral toxic side effects of cisplatin. Two different therapeutic doses of memantine (5 mg/kg) and (10 mg/kg) were orally administered for 30 days to 50 male BALB/c mice divided into 5 groups: G1: no treatment; G2: cisplatin treatment; G3: memantine treatment; G4: pretreatment of (5 mg/kg) memantine with cisplatin (4 mg/kg); G5: pretreatment of 10 mg/kg memantine with cisplatin (4 mg/kg). Weekly neurobehavioral investigations were conducted using the following battery of tests: open field activity, negative geotaxis, hole-board test, swimming test, and calculation of weight. At the end of the experimental period the mice were euthanized, and immunohistochemistry was then used to measure the expression scores of nicotinic acetylcholine receptors (nAChRs) in the muscles and brain. Results revealed that mice in G2 showed a significant decrease in the ability to perform neurobehavioral tasks. The mice in G5 exhibited a significantly improved ability on these tests, indicating a complete neurobehavioral protective effect, while the mice in G4 showed partial protection. The nAChRs score showed higher expression in the case of G2 in comparison with G3, G4, and G5. Weight loss was exhibited in G2, while in G3 and G1 these values were normal. A therapeutic dose of memantine 10 mg/kg yielded more protection than 5 mg/kg in the treatment of neuropathy; this highlights the importance of using memantine to decrease the main side effects of cisplatin.

New Findings in the Signaling Pathways of cis and trans Platinum Iodido Complexes' Interaction with DNA of Cancer Cells

We have selected a series of aliphatic amine platinum compounds bearing chloride and/or iodide as the leaving groups. The complexes' cytotoxicity and interaction with DNA indicated differences in the reactivity. Now, we are reporting on the analysis of their molecular mechanism of action on gastric cancer cells. Our data reveals differences between them. Chlorido drugs showed similar behavior to cisplatin; they both required p53 to induce apoptosis but only cis-ipa showed DNA damage requirement for apoptosis induction. On the contrary, cis and trans iodido induced cell death independent of p53 activity, and they induced cell death through Bid activation, so their toxicity could be enhanced in a combined treatment with novel Bcl-2 protein family inhibitors. We also report the structural features of the DNA adduct for one of the complexes by X-ray diffraction. These findings represent a step forward in the search for new platinum-derived agents more specific and effective in the treatment of cancer.

Amniotic fluid stem cells ameliorate cisplatin-induced acute renal failure through induction of autophagy and inhibition of apoptosis

BACKGROUND

We have recently demonstrated that amniotic fluid stem cells (AFSC) express renal progenitor markers and can be differentiated in vitro into renal lineage cell types, viz, juxtaglomerular and renal proximal tubular epithelial-like cells. Here, we have evaluated the therapeutic efficacy of AFSC in a cisplatin-induced rat model of acute renal failure (ARF) and investigated the underlying mechanisms responsible for their renoprotective effects.

METHODS

ARF was induced in Wistar rats by intra-peritoneal injection of cisplatin (7 mg/kg). Five days after cisplatin injection, rats were randomized into two groups and injected with either AFSC or normal saline intravenously. On days 8 and 12 after cisplatin injection, the blood biochemical parameters, histopathological changes, apoptosis and expression of pro-apoptotic, anti-apoptotic, and autophagy-related proteins in renal tissues were studied in both groups of rats. To further confirm whether the protective effects of AFSC on cisplatin-induced apoptosis were dependent on autophagy, chloroquine, an autophagy inhibitor, was administered by the intra-peritoneal route.

RESULTS

Administration of AFSC in ARF rats resulted in improvement of renal function and attenuation of renal damage as reflected by significant decrease in blood urea nitrogen, serum creatinine levels, tubular cell apoptosis as assessed by Bax/Bcl2 ratio, and expression of the pro-apoptotic proteins, viz, PUMA, Bax, cleaved caspase-3, and cleaved caspase-9, as compared to the saline-treated group. Furthermore, in the AFSC-treated group as compared to the saline-treated group, there was a significant increase in the activation of autophagy as evident by increased expression of LC3-II, ATG5, ATG7, Beclin1, and phospho-AMPK levels with a concomitant decrease in phospho-p70S6K and p62 expression levels. Chloroquine administration led to significant reduction in the anti-apoptotic effects of the AFSC therapy and further deterioration in the renal structure and function caused by cisplatin.

CONCLUSION

AFSC led to amelioration of cisplatin-induced ARF which was mediated by inhibition of apoptosis and activation of autophagy. The protective effects of AFSC were blunted by chloroquine, an inhibitor of autophagy, highlighting that activation of autophagy is an important mechanism of action for the protective role of AFSC in cisplatin-induced renal injury.

Piceatannol protects against cisplatin nephrotoxicity via activation of Nrf2/HO-1 pathway and hindering NF-κB inflammatory cascade

This study investigates the molecular mechanisms of the nephroprotective effect of piceatannol (PIC) against cisplatin-induced nephrotoxicity in rats. PIC (10 mg/kg i.p.) was given for 7 days, starting 2 days before cisplatin single injection (7 mg/kg i.p.). Serum creatinine, blood urea nitrogen (BUN), kidney injury molecule 1, and neutrophil gelatinase-associated lipocalin were used as nephrotoxicity markers. Oxidative stress, inflammatory, and apoptotic markers were determined. In addition, the role of PIC in Nrf2 activation and its subsequent induction of antioxidant enzymes, as well as its potential cross talk with nuclear factor kappa-B, were addressed. PIC reversed cisplatin-induced elevation of nephrotoxicity markers and restored the normal kidney ultrastructure. PIC attenuated cisplatin-induced reduction in Nrf2 expression and the relative mRNA level of antioxidant enzymes: hemeoxygenase-1, cysteine ligase catalytic, and modifier subunits, as well as superoxide dismutase and glutathione-S-transferase activities. Cisplatin pro-inflammatory response was reduced by PIC treatment as evidenced by the suppression of nuclear factor kappa-B activation and the subsequent decreased tissue levels of interleukin-1β, tumor necrosis factor-α, cyclooxygenase-2, and inducible nitric oxide synthase. PIC suppressed cisplatin-induced apoptosis by decreasing p53 and cytochrome C expression and caspase-3 activity. Therefore, PIC may protect against cisplatin-induced nephrotoxicity by modulating Nrf2/HO-1 signaling and hindering the inflammatory and apoptotic pathways.

New Insights in the Pathogenesis of Cisplatin-Induced Nephrotoxicity

Cisplatin (cis-diamminedichloroplatinum II) is a widely used chemotherapeutic agent. However, efficacy and clinical utility of this drug is significantly limited by severe side effects such as nephrotoxicity which develops due to renal accumulation and bio-transformation in proximal tubular epithelial cells. Cisplatin-induced nephrotoxicity can be manifested as acute kidney injury (AKI), or as different types of tubulopathies, salt wasting, loss of urinary concentrating ability, and magnesium wasting. The attenuation of cisplatin-caused AKI is currently accomplished by hydration, magnesium supplementation or mannitol-induced forced diuresis. However, mannitol treatment causes over-diuresis and consequent dehydration, indicating an urgent need for the clinical use of newly designed, safe and efficacious renoprotective drug, as an additive therapy for high dose cisplatin-treated patients. Accordingly, we emphasized current knowledge regarding molecular mechanisms responsible for cisplatin-caused nephrotoxicity and we described in detail the main clinical manifestations of cisplatin-induced renal dysfunction in order to pave the way for the design of new therapeutic approaches that can minimize detrimental effects of cisplatin in the kidneys. Having in mind that most of cisplatin-induced cytotoxic effects against renal cells are, at the same time, involved in anti-tumor activity of cisplatin, new nephroprotective therapeutic strategies have to prevent renal injury and inflammation without affecting cisplatin-induced toxicity against malignant cells.

Advances in Toxicological Research of the Anticancer Drug Cisplatin

Cisplatin is one of the most widely used chemotherapeutic agents for various solid tumors in the clinic due to its high efficacy and broad spectrum. The antineoplastic activity of cisplatin is mainly due to its ability to cross-link with DNA, thus blocking transcription and replication. Unfortunately, the clinical use of cisplatin is limited by its severe, dose-dependent toxic side effects. There are approximately 40 specific toxicities of cisplatin, among which nephrotoxicity is the most common one. Other common side effects include ototoxicity, neurotoxicity, gastrointestinal toxicity, hematological toxicity, cardiotoxicity, and hepatotoxicity. These side effects together reduce the life quality of patients and require lowering the dosage of the drug, even stopping administration, thus weakening the treatment effect. Few effective measures exist clinically against these side effects because the exact mechanisms of various side effects from cisplatin remain still unclear. Therefore, substantial effort has been made to explore the complicated biochemical processes involved in the toxicology of cisplatin, aiming to identify effective ways to reduce or eradicate its toxicity. This review summarizes and reviews the updated advances in the toxicological research of cisplatin. We anticipate to provide insights into the understanding of the mechanisms underlying the side effects of cisplatin and designing comprehensive therapeutic strategies involving cisplatin.

Acylated Ghrelin Renders Chemosensitive Ovarian Cancer Cells Resistant to Cisplatin Chemotherapy via Activation of the PI3K/Akt/mTOR Survival Pathway

This study investigated the effect of acylated synthetic ghrelin (AG) on the survival and proliferation of human chemosensitive ovarian cancer cells (A2780) and explored some mechanisms of action with a focus on the p53 apoptotic pathway and PI3K/Akt and NF-κB survival pathways. Human A2780 ovarian cancer cells were cultured with or without AG treatment in the presence or absence of cisplatin. In some cases, cisplatin+AG-treated cells were pre-incubated either with [D-Lys3]-GHRP-6, a ghrelin receptor antagonist, or with LY294002, a PI3K inhibitor. mRNA of ghrelin receptors(GHS-R1a and GHS-R1b), as well as, protein levels of GHS-R1a, were expressed abundantly in A2780 cells. AG treatment did not affect the mRNA and protein levels of GHS-R1a and GHS-R1b in both control and Cis-treated cells. However, while AG treatment had no effect on control cell viability, it significantly increased cell viability and proliferation and inhibited cell death in Cis-treated cells. In both control and Cis-treated cells, AG treatment significantly increased PI3K/Akt/mTOR signaling and enhanced the nuclear accumulation of NF-κB. Concomitantly, in both control and Cis-treated cells, AG significantly lowered the protein levels of p53, p-p53 (Ser16), PUMA, cytochrome C, and cleaved caspase-3. Interestingly, pre-incubating the cells with either [D-Lys3]-GHRP-6 or LY294002 completely abolished the above-mentioned effect of AG in both control and Cis-treated cells. In conclusion, the findings of this study show that AG promotes cell survival of the OC cells and renders them resistat to Cis therapy, an effect that is mediated by the activation of PI3K/Akt/mTOR and activation of NF-κB, and requires GHS-R1a.