The brown algae: Sargassum binderi sonder bears potential nephroprotective activity in in-vivo experimental model.

OBJECTIVES: This study aimed to investigate the protective activity of brown seaweed, the ethanolic and water extracts of Sargassum binderi (S. binderi) were examined. Anticancer drug, cisplatin is normally used for the treatment of solid tumors that cause acute kidney damage after assemblage in the renal tubules. MATERIAL AND METHODS: It was an acute nephrotoxicity study, animals were divided into several groups randomly, cisplatin (7mg/kg i.p.) and normal saline were used as positive and negative control respectively. The S. bindari ethanolic and water extract were given orally in a dose of 200mg/kg for 5days. Various biomarkers were assessed to observe the nephroprotective potential, while antioxidant activities were investigated using reduced glutathione, catalase and malondialdehyde as oxidative stress. GCMS was performed to validate the presence of important therapeutic moieties. RESULTS: The current result justified that pretreatment with S. binderi inhibited the elevation of antioxidant parameters and also showed protection against lipid peroxidation, induced by cisplatin challenge. The overall impact was the nephroprotection, which has been revealed from the results. GCMS evaluation of hexanes fraction revealed the presence of therapeutically important compounds including heptasiloxane, 3,7,11,15-tetramethyl-2-hexadecen-1-ol, hexadecamethyl, cyclooctasiloxane, and hexadecamethyl. These compounds have been reported for their antioxidant, antibacterial, anticancer, and antifungal activities. CONCLUSION: S. binderi showed reno-protective effect by checking their well-known biochemical parameters probably due to the antioxidant activity as confirmed by the presence of compounds.

[Preoperative chemotherapy for patients with upper tract urothelial carcinoma: Impact on renal function]. / Chimiothérapie préopératoire des tumeurs des voies excrétrices supérieures : impact sur la fonction rénale.

PURPOSE: Upper tract urothelial carcinoma (UTUC) are rare tumors with a poor prognosis. The standard treatment for localized disease is based on total nephroureterectomy (NUT) followed by platinum-based adjuvant chemotherapy for eligible patients at risk of recurrence. However, many patients have renal failure after surgery preventing chemotherapy. Thus, the place of preoperative chemotherapy (POC) is questioned with little information available about renal toxicity and efficacity. METHODS: A single center retrospective study was performed on patients with UTUC who received POC. RESULTS: In all, 24 patients with localized UTUC were treated with POC between 2013 and 2022. Twenty-one (91%) had secondarily NUT. In this cohort, POC did not result in degradation of median renal function (pre-POC median GFR: 70mL/min, post-POC median GFR: 77mL/min, P=0.79), unlike NUT (post-NUT median GFR: 51.5mL/min, P<0.001). In addition, the rate of complete pathological response to pathological examination was 29%. After a median follow-up of 27.4 months, the overall survival rate was 74% and the recurrence-free survival rate was 46%. CONCLUSION: POC for UTUC shows a very reassuring renal toxicity profile and encouraging histological results. These data encourage prospective studies assessing its place for UTUC management.

BRD4 promotes the migration and invasion of bladder cancer cells through the Sonic hedgehog signaling pathway and enhances cisplatin resistance.

Platinum-based chemotherapy is a widely used strategy for bladder cancer (BCa) treatment. However, its clinical efficacy is affected by chemotherapy resistance via complex molecular mechanisms. Therefore, there is an urgent need to explore new targets for BCa therapy. Here, we showed that bromodomain-4 protein (BRD4) expression is upregulated in BCa tissues and cells. Inhibition of BRD4 attenuated the migration and invasion of BCa cells, which was rescued by the Sonic hedgehog (SHH) pathway activator recombinant human Sonic hedgehog peptide (rhSHH). We further found that cisplatin (DDP) suppressed the migration and invasion of BCa cells in vitro and inhibited tumor growth in vivo. However, overexpression of BRD4 weakened the pharmacological effects of DDP. In brief, our research revealed that BRD4 promotes migration and invasion by positively regulating the SHH pathway, drives DDP resistance in BCa, and is a novel therapeutic target for the treatment of BCa.

Protective effects of sildenafil administration on chemotherapeutic-induced ovarian damage in rats.

Agents to reduce the gonadotoxic effects of chemotherapeutics are still under investigation. In this context, we aimed to investigate the protective effect of sildenafil against chemotherapeutic-induced gonadotoxicity in a rat model. A total of 62 female rats were divided into eight groups as control, sildenafil (1.4 mg/kg, orally), doxorubicin (3 mg/kg, i.p.), cisplatin (5 mg/kg, i.p.), cyclophosphamide (200 mg/kg, i.p.), doxorubicin+sildenafil, cisplatin+sildenafil, and cyclophosphamide+sildenafil (1.4 mg/kg orally sildenafil in addition to the same dose of chemotherapeutics). The groups were compared in terms of follicle count, ovarian size, and anti-müllerian hormone (AMH) levels. Use of sildenafil with cyclophosphamide was effective only in preserving primary follicle count (p = 0.026) and had no significant change in the secondary follicle count, ovarian size, or AMH level. Adding sildenafil to cisplatin had a significant protective effect on primary follicle count (p = 0.011), secondary follicle count (p = 0.009), and ovarian size (p = 0.001), but this effect could not be demonstrated at AMH level. Sildenafil was not effective on any parameter in the doxorubicin group. Sildenafil may be effective in reducing the gonadotoxicity associated with the use of cisplatin and cyclophosphamide.

Blockade of chloride channel-3 enhances cisplatin sensitivity of cholangiocarcinoma cells though inhibiting autophagy.

Chemotherapy is one of the most important strategies in the treatment of cancer; however, chemoresistance restricts the effect of chemotherapy. Growing reports suggest that chloride channel-3 (ClC-3) is involved in regulating the sensitivity of multiple chemotherapeutic agents in the chemotherapy of various tumours, while its role in the chemotherapy of cholangiocarcinoma (CCA) is still poorly understood. Herein, we observed that ClC-3 was highly expressed in CCA chemoresistant tissues and CCA cisplatin-resistant cells QBC939/DDP, and the sensitivities of QBC939 and QBC939/DDP cells to cisplatin were all increased after inhibition of ClC-3. Further mechanism exploration revealed that ClC-3 knockdown reduced the level of autophagy. Furthermore, in both QBC939 and QBC939/DDP cells, the autophagy agonist rapamycin eliminated the increased cisplatin sensitivity of ClC-3 knockdown without affecting ClC-3 expression. Collectively, all the findings demonstrate that ClC-3 knockdown increases cisplatin-induced cell death in CCA cells though inhibiting autophagy, regardless of the occurrence of cisplatin resistance. In addition, our results also suggest that targeted inhibition of ClC-3 may be a potential strategy for chemosensitization in CCA chemotherapy.

Endothelin system expression in the kidney following cisplatin-induced acute kidney injury in male and female mice.

The chemotherapeutic agent cisplatin accumulates in the kidney and induces acute kidney injury (AKI). Preclinical and clinical studies suggest that young female mice and women show greater recovery from cisplatin-AKI compared to young male mice and men. The endothelin (ET) and ET receptors are enriched in the kidney and may be dysfunctional in cisplatin-AKI; however, there is a gap in our knowledge about the putative effects of sex and cisplatin on the renal ET system. We hypothesized that cisplatin-AKI male and female mice will have increased expression of the renal ET system. As expected, all cisplatin-AKI mice had kidney damage and body weight loss greater than control mice. Cisplatin-AKI mice had greater cortical Edn1, Edn3, Ednra, and Ednrb, while outer medullary Ednra was significantly suppressed in both sexes. Of the ∼25 000 genes sequenced from the inner medulla, only 91 genes (comparing saline mice) and 134 genes (comparing cisplatin-AKI mice) were differentially expressed and they were unrelated to the ET system. However, Edn1 was significantly greater in the inner medulla of male and female cisplatin-AKI mice. Thus, RNA profiles of the ET system were significantly affected by cisplatin-AKI throughout the kidney regardless of sex and this may help determine the therapeutic potential of targeting the ET receptors in cisplatin-AKI.

Wnt/ß-catenin inhibitor pyrivinium attenuates cisplatin-induced acute kidney injury by possibly reducing platinum uptake and accumulation mediated by reduced organic cation transporter-2 expressions.

Aberrant activation of Wnt/ß-catenin induces renal dysfunction by initiating pro-apoptotic cascades, fibrosis, oxidative and inflammatory burden. This study tested the therapeutic effects of Wnt/ß-catenin inhibitor pyrvinium against cisplatin-induced acute kidney injury (AKI) in rats. Cisplatin was administered at a single dose of 5 mg/kg (i.p.) and renal cisplatin accumulation and uptake in cortical slices were determined after the fifth day by atomic absorption spectroscopy. Levels of pro-inflammatory cytokines were checked by ELISA, and organic cation transporter-2 (OCT-2) transcription and expression in renal tissue were evaluated by RT-PCR and immunohistochemical technique. Cisplatin administration produced renal dysfunction manifested as increase in serum creatinine, blood urea nitrogen, proteinuria, reduced clearance and electrolyte imbalance. Oxidative stress indices, pro-inflammatory cytokines, fibronectin, and caspase-3 activity were elevated in cisplatin-challenged rats. Moreover, increased renal OCT-2 transcription and immunostaining were detected in cisplatin kidneys which resulted in platinum accumulation. Additional docking studies depicted strong interaction between the ß-catenin and OCT-2 protein. These manifestations induced mitochondrial dysfunction, histological damage and fibrosis. Notably, Wnt/ß-catenin inhibitor pyrvinium (60 µg/kg; p.o.) treatment reduced the renal OCT-2 gene transcription causing a decline in platinum levels. Thus, the present study concludes that Wnt/ß-catenin inhibition attenuates cisplatin-induced AKI in rats, partly by down-regulating OCT-2 expression.

Upregulation of exonuclease 1 caused by homology-dependent repair confers cisplatin resistance to gastric cancer cells.

The homology-dependent repair (HDR) pathway is involved in deoxyribonucleic acid (DNA) damage response (DDR), which is crucial to cancer cell survival after treatment with DNA damage agents, including cisplatin (CDDP). Here, we explored the interactions between exonuclease 1 (EXO1), a core gene in the HDR pathway, and CDDP resistance in gastric cancer (GC). Using bioinformatics analysis, we identified the HDR pathway as the most amplified pathway in DDR in GC. In addition, EXO1 was the core gene in the HDR pathway and showed the most significant amplification in GC. The amplification of EXO1 resulted in higher EXO1 expression in cancerous tissues, with malignant prognostic effects. Moreover, we upregulated or downregulated EXO1 in GC cells to examine its effects on the cell malignant phenotype and CDDP resistance in vitro and in vivo. The depletion of EXO1 inhibited cell proliferatory, migratory, and invasive activities, and provided apoptosis resistance to GC cells. EXO1 expression was elevated in CDDP-resistant cells. Ectopic expression of EXO1 increased the resistance of GC cells to CDDP, while downregulation of EXO1 increased the sensitivity of GC cells. Taken together, our study indicates that the HDR pathway is an important player in CDDP resistance in GC through the regulation of EXO1.

Synergistic effects of autophagy inhibitors combined with cisplatin against cisplatin-resistant nasopharyngeal cancer cells.

This study explored the synergistic effects of autophagy inhibitors combined with cisplatin against cisplatin-resistant nasopharyngeal cancer cells by treating HNE-1 and cisplatin (diamminedichloroplatinum; DDP)-resistant HNE1/DDP nasopharyngeal cancer cell lines with DDP, autophagy inhibitors, or a combination of autophagy inhibitors and DDP. Cell viability was determined via MTT (colorimetric) and colony-forming assays, and the rate of apoptosis was determined using propidium iodide (PI) and annexin V double-staining. The expressions of proteins were determined by Western blotting. For our in-vivo studies, a murine xenograft model was established to evaluate the anti-tumor effects of the combination of autophagy inhibitor and DDP. The results showed that treatment with DDP increased the expressions of ATP-binding cassette sub-family B member 1 (ABCB1), ATP Binding Cassette Subfamily C Member 1 (ABCC1), and P-glycoprotein 1 (P-gp) in the HNE1/DDP cell lines. Treatment with chloroquine decreased the expression levels of ABCB1, ABCC1, and P-gp, and increased the formation of LC3-II and the expression levels of p62 in the HNE1/DDP cells. Additionally, the combination of autophagy inhibitors and DDP produced a synergistic effect on DDP-induced cell death and apoptosis. Furthermore, the combination of the autophagy inhibitor and DDP showed significant anti-tumor effects in the xenograft mouse model. In summary, autophagy inhibitors show synergistic anti-tumor effects with DDP in vitro against DDP-resistant nasopharyngeal cancer cells and in vivo in our xenograft murine model.

Resveratrol upregulates miR-455-5p to antagonize cisplatin ototoxicity via modulating the PTEN-PI3K-AKT axis.

Resveratrol is a non-flavonoid polyphenol compound that exists in many plants, and is considered an antitoxin. This study explores the effects from the regulation of miR-455-5p by resveratrol on cisplatin-induced ototoxicity via the PTEN-PI3K-AKT signaling pathway. For this, House Ear Institute-Organ of Corti 1 (HEI-OC1) cells were transfected with miR-455-5p inhibitor and treated with cisplatin and resveratrol, then cell proliferation, apoptosis, and oxidative stress were evaluated. A mouse model of hearing loss was established, and these mice were treated with cisplatin, resveratrol, or cisplatin combined with resveratrol, by intraperitoneal injection. The auditory brainstem response (ABR) threshold was measured, and hair cells were examined using immunofluorescence staining. The expression levels of miR-455-5p, PTEN, and PI3K/Akt proteins were examined. The results from our in-vitro experiments indicate that resveratrol promoted viability and reduced apoptosis and oxidative stress in cisplatin-induced HEI-OC1 cells. Resveratrol upregulated miR-455-5p, downregulated PTEN, and activated the PI3K-Akt axis. These effects of resveratrol were reversed by knock-down of miR-455-5p. The results from our in-vivo experiments indicate that resveratrol protected hearing and inhibited the hair-cell injury caused by cisplatin ototoxicity. Resveratrol also upregulated miR-455-5p, downregulated PTEN, and activated the PTEN-PI3K-Akt axis in cochlear tissues from cisplatin-treated mice. These results indicate that resveratrol upregulates miR-455-5p to target PTEN and activate the PI3K-Akt signaling pathway to counteract cisplatin ototoxicity.

Redox and apoptotic potential of novel ruthenium complexes in rat blood and heart.

Ruthenium(II) complexes offer the potential for lower toxicity compared with platinum(II) complexes. Our study aimed to compare cardiotoxicity of [Ru(Cl-tpy)(en)Cl][Cl], [Ru(Cl-tpy)(dach)Cl][Cl], [Ru(Cl-tpy)(bpy)Cl][Cl], cisplatin, and saline through assessment of redox status and relative expression of apoptosis-related genes. A total of 40 Wistar albino rats were divided into five groups. Ruthenium groups received a single dose of complexes intraperitoneally (4 mg/kg/week) for a 4-week period; cisplatin group received cisplatin (4 mg/kg/week) and control group received saline (4 mL/kg/week) in the same manner as ruthenium groups. In collected blood and heart tissue samples, spectrophotometric determination of oxidative stress biomarkers was performed. The relative expression of apoptosis-related genes (Bcl-2, Bax, and caspase-3) in hearts was examined by real-time polymerase chain reaction. Our results showed that systemic and cardiac pro-oxidative markers (thiobarbituric acid reactive substances and nitrite) were significantly lower in ruthenium groups compared with cisplatin group, while concentrations of antioxidative parameters (catalase, superoxide dismutase, and oxidized glutathione) were significantly higher. Ruthenium administration led to significantly lower gene expression of Bax and caspase-3 compared with cisplatin-treated rats, while Bcl-2 remained unchanged. Applied ruthenium complexes have less pronounced potential for induction of oxidative stress-mediated cardiotoxicity compared with cisplatin. These findings may help for future studies that should clarify the mechanisms of cardiotoxicity of ruthenium-based metallodrugs.

Morphometric analysis of structural renal alterations and beneficial effects of aminoguanidine in acute kidney injury induced by cisplatin in rats.

Since cisplatin-induced nephrotoxicity has very important clinical consequences, the purpose of this study was to determine the potential protective effect of aminoguanidine on the acute kidney injury caused by cisplatin. Experiments were done on 40 Wistar rats divided into four groups. The CIS group received cisplatin in a single dose of 8 mg/kg, while the CISAG group received the same dose of cisplatin and aminoguanidine (100 mg/kg) by intraperitoneal injections. Animals in the AG group received only aminoguanidine (100 mg/kg) and those in the C group received saline. Quantitative evaluation of structural and functional alterations in the kidneys was performed by analysis of biochemical and parameters of oxidative stress and by histological and morphometric analysis of renal sections. Histological sections of kidney showed structural damage of proximal tubules and glomeruli that were induced by cisplatin. Morphometric analysis revealed statistically significant differences in the area of proximal tubules and the size and cellularity of glomeruli between the CIS and CISAG groups. Glomerular basement membrane thickness was increased in the CIS group, while aminoguanidine attenuated these changes in the CISAG group of rats. Our results suggest that aminoguanidine acts protectively and repairs structural and functional damage of kidney by engaging the existent antioxidative potential at the level of renal tissue.

Inhibition of autophagy improves resistance and enhances sensitivity of gastric cancer cells to cisplatin.

Autophagy plays critical roles in tumorigenesis, while the effects of autophagy on chemoresistance of cancer cells had great disparity. This study aims to explore the impacts of autophagy on the sensitivity and resistance of gastric cancer cells to cisplatin (DDP). We firstly demonstrated that there was stronger autophagy activity in gastric cancer SGC-7901 cells than that in DDP-resisting SGC-7901/DDP cells. Then, we discovered that inhibiting autophagy by chloroquine (CQ) significantly enhanced the proliferation-inhibiting and apoptosis-inducing effects of DDP to SGC-7901 and SGC-7901/DDP cells. Moreover, CQ could partially reverse the resistance of SGC-7901/DDP cells to DDP in a concentration-dependent manner. However, the autophagy inducer everolimus (RAD001) had no obvious effects on the sensitivity of gastric cells to DDP. Mechanistically, we demonstrated that CQ might enhance the sensitivity of SGC-7901cells and improve the resistance of SGC-7901/DDP cells to DDP through inhibiting the mTORC1 pathway, especially to SGC-7901/DDP cells. Additionally, we found interfering Beclin-1 using Beclin-1 shRNA also enhanced the proliferation-inhibiting and apoptosis-inducing effects of DDP on gastric cancer cells by inhibiting phosphorylation of Akt. Our study shows that inhibiting autophagy could improve the chemoresistance and enhanced sensitivity of gastric cancer cells to DDP and provide a rationale for the administration of cisplatin combined with CQ for treating patients with gastric cancer.

Caffeic acid phenethyl ester attenuates changes in pancreatic tissue damage biomarkers induced by cisplatin.

Application of cisplatin (CP) for the treatment of different cancers is known to cause pancreatitis through an increase in reactive oxygen species production and promotion of inflammation. Caffeic acid phenethyl ester (CAPE), the main activity carrier of propolis extracts, was previously found to possess numerous beneficial properties. This study aims to determine for the first time the potential of CAPE in preventing CP-induced pancreatic tissue damage by studying the changes occurring on both biochemical and microscopic levels. The levels of serum α-amylase and a panel of pancreatic tissue biomarkers related to tissue injury (reduced glutathione, xanthine oxidase, malondialdehyde, and protein carbonylated concentration) and inflammation (myeloperoxidase, nitric oxide, and umor necrosis factor alpha) were studied in male Wistar rats treated with either CP alone or with CP and CAPE. Additionally, microscopic analysis of pancreatic tissue would be conducted as well. Application of CAPE together with CP statistically significantly prevented the disturbance in all here-studied pancreatic tissue damage and inflammation-related biomarkers. The changes in pancreas biochemical status was followed by morphological disturbance. The results of the present study suggest that CAPE could act as a protective agent in pancreatic damage that arises after CP application.

Ambroxol attenuates cisplatin-induced hepatotoxicity and nephrotoxicity via inhibition of p-JNK/p-ERK.

Hepatotoxicity and nephrotoxicity are important drawbacks of cisplatin. The objective of this study is to evaluate the ability of ambroxol in 2 different doses (35 and 70 mg/kg, i.p.) to protect liver and kidney from damage induced by a single dose of cisplatin (10 mg/kg, i.p.) in comparison with N-acetylcysteine (250 mg/kg, i.p.). Inflammatory, oxidative stress, and apoptotic biomarkers were investigated to show the influence of ambroxol on hepatotoxicity and nephrotoxicity. Ambroxol decreased the elevated activity of liver enzymes (aspartate aminotransferase and alanine aminotransferase) and kidney function tests (blood urea nitrogen and creatinine). Ambroxol mitigated cisplatin inflammatory damage by inhibition of tumor necrosis factor-α, interleukin-1ß, and nuclear factor kappa-B and elevation of nuclear factor erythroid 2-related factor 2. Moreover, ambroxol inhibited oxidative damage indicated by reduction of malondialdehyde and replenished the store of reduced glutathione likely by upregulating glutathione reductase and superoxide dismutase. Elevation of phosphorylated c-Jun N-terminal kinases (p-JNK) and phosphorylated extracellular signal-regulated kinase (p-ERK) were attenuated by ambroxol associated with a decrease in the expression of caspase-3; these results were consistent with histopathological results. These results recommend ambroxol to be co-administered with cisplatin in cancer patients to ameliorate liver and kidney damage, and this was confirmed by MTT assay.

Apoptosis perturbations and expression of regulatory inflammatory factors in cisplatin-depleted rat livers under l-arginine protection.

Hepatic injury is one of the most common complications associated with cisplatin (CIS) use. Recently, liver protection lines are being discovered to stop the hepatic cell death due to inflammatory and apoptotic perturbations. l-arginine has protective effects in several models of liver injury. This study was designed to investigate the possible protective effect of l-arginine against CIS-induced acute hepatic injury in rats. Rats were divided into 4 groups: control, l-arginine, CIS, l-arginine + CIS. Liver function, oxidative stress, inflammatory cytokines, and apoptosis markers were assessed. l-arginine pretreatment protected the liver against CIS-induced toxicity as indicated by significantly alleviating the changes in liver function along with restoration of the antioxidant status. This finding was confirmed with the markedly improved pathological changes. l-arginine showed anti-inflammatory effect through the reduction of liver expression of iNOS, TNF-α, and NF-κß, which were ameliorated to significant levels. Furthermore, l-arginine administration downregulated the liver expression of the apoptotic marker, caspase-3. The results recommend l-arginine as a hepatoprotective agent against CIS toxicity. Mostly, this hepatoprotective effect of l-arginine involved anti-inflammatory and anti-apoptotic activities.

miRNA-34a decreases ovarian cancer cell proliferation and chemoresistance by targeting HDAC1.

This study aimed to explore the roles of miRNA-34a (miR-34a) in ovarian cancer (OC) cells and uncover possible mechanisms. The proliferation of OC cells was measured with an MTT assay and soft agar colony formation assay. TargetScan analysis, real-time PCR, and a luciferase reporter assay were used to demonstrate the downstream target of miR-34a in OC cells. HDAC1 expression levels were detected by immunoblot analysis. miR-34a inhibited the proliferation of SKOV3 and OVCA433 cells and enhanced cisplatin sensitivity in cisplatin-resistant SKOV3cp cells. The results of TargetScan analysis, real-time PCR, and luciferase reporter assay confirmed that miR-34a downregulated HDAC1 expression by directly targeting the 3'-UTR of HDAC1 mRNA. The overexpression of HDAC1 decreased cisplatin sensitivity and promoted proliferation in OC cells. MTT assay and soft agar colony formation assay showed that HDAC1 overexpression blocked the suppressive effects of miR-34a on SKOV3 cell proliferation. In addition, treatment with the miR-34a mimic partially recovered the cisplatin sensitivity of SKOV3cp cells, whereas HDAC1 overexpression blocked the above phenomena caused by treatment with the miR-34a mimic. miR-34a exhibited suppressive effects on OC cells via directly binding and downregulating HDAC1 expression, which subsequently decreased the resistance to cisplatin and suppressed proliferation in OC cells.

Combined but not single administration of vitamin C and l-carnitine ameliorates cisplatin-induced gastric mucosa damage in male rats.

Although cisplatin is a potent anticancer drug, it instigates oxidative and pro-inflammatory reactions that pose significant and distressing clinical symptoms. Therefore, this study investigated the effects of vitamin C and (or) l-carnitine on cisplatin-induced gastric mucosa damage in rat. The rats were allocated into 6 groups (n = 5). The control group received distilled water, while the treatment groups received cisplatin alone (CIP), or cisplatin with vitamin C, l-carnitine, or their combination. Cisplatin caused disruption of the gastric mucosa histoarchitecture and altered the mucus barrier function. Moreover, the stomach tissue of the CIP-treated group showed increased levels of oxidative stress markers (malondialdehyde and H2O2) and decreased activities of antioxidant (superoxide dismutase, glutathione peroxidase, catalase, glutathione S-transferase) and non-antioxidant (reduced glutathione) enzymes. These deleterious events were accompanied with significant increases in pro-inflammatory cytokines and inflammatory infiltration markers, myeloperoxidase and inducible nitric oxide synthase. However, the administration of both vitamin C and l-carnitine, and not either of the two showed additive effects in attenuating the adverse effects of cisplatin. The histological results agreed with the biochemical assays. The study concluded that the combined administration of vitamin C and l-carnitine, but not the single therapy, could prevent the adverse effects of cisplatin on gastric tissue.

PRPS1 silencing reverses cisplatin resistance in human breast cancer cells.

PRPS1 (phosphoribosyl pyrophosphate synthetase 1), which drives the nucleotide biosynthesis pathway, modulates a variety of functions by providing central building blocks and cofactors for cell homeostasis. As tumor cells often display abnormal nucleotide metabolism, dysregulated de-novo nucleotide synthesis has potential impacts in cancers. We now report that PRPS1 is specifically and highly expressed in chemoresistant (CR) cancer cells derived from cisplatin-resistant human breast cancer cell lines SK-BR-3 and MCF-7. The inhibition of PRPS1 activity in CR cells by genetic silencing reduces cell viability and increases apoptosis in vitro, both of which can be further potentiated by cisplatin treatment. Significantly, such down-regulation of PRPS1 in CR cells when administered to nude mice enhanced the survival of those animals, as demonstrated by decreased tumor growth. Knockdown of PRPSI may cause these effects by potently inducing autonomous activation of caspase-3 and inhibiting the proliferation in the engrafted CR tumors. As a result, cisplatin sensitivity in a xenograft model of CR cancer cells can be restored by the down-regulation of PRPS1. Thus, PRPS1 inhibition may afford a therapeutic approach to relapsed patients with breast cancer, resistant to chemotherapy.

The protective effect of trimetazidine against cisplatin-induced nephrotoxicity in rats.

Nephrotoxicity is a dose-limiting side effect of cisplatin (CSP). The study investigated the possible protective role of trimetazidine (TMZ) against CSP-induced nephrotoxicity in rats. Rats were divided into four groups; control, TMZ, CSP, and CSP + TMZ. The CSP group showed significant deterioration in kidney function with structural changes in the form of interstitial hemorrhage, glomeruli shrinkage and peritublar capillary congestion, tubular cells vacuolation, pyknosis, shedding and necrosis, and inflammatory cell infiltrates, all indicating renal damage. CSP also caused a significant increase in the lipid peroxidation marker malondialdehyde (MDA) levels, renal nuclear factor kappa B (NF-κB) DNA-binding activity and protein expression, and tumor necrosis factor alpha (TNF-α) and IL-6 levels. Treatment with TMZ before and after CSP injection produced significant improvement of kidney function and histopathology. TMZ treatment also significantly attenuated CSP-induced oxidative stress and suppressed elevated levels of TNF-α and IL-6 and NF-κB expression and its DNA-binding activity caused by CSP administration. TMZ has a protective effect against CSP-induced nephrotoxicity mediated by reduction of oxidative stress and attenuation of CSP-induced inflammation.