Cisplatin toxicity in the developing brain displays an absolute requirement for caspase-3

Effect of tangeretin on cisplatin-induced oxido-inflammatory brain damage in rats

Cisplatin (CIS) is a platinum-derived chemotherapeutic agent commonly utilized in the treatment of various malignant tumours. However, anticancer doses of the drug cause serious damage to the brain. This study aimed to determine the potential protective effects of tangeretin, which has antioxidant and anti-inflammatory properties, in cisplatin-induced neurotoxicity on BALB/c mice brains. Male BALB/c mice were randomized and separated into four groups. Tangeretin was given for 10 days by gavage. CIS was injected as a single dose of 10 mg/kg intraperitoneally (ip) on the 10th day. Brain tissues, malondialdehyde (MDA), total glutathione (tGSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT) and nitric oxide (NO) levels were measured to determine oxidative damage and myeloperoxidase, tumour necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1β), IL-6 and IL-10 were measured to determine inflammatory activity. In addition, 8-OHdG and caspase-3 were analysed by immunofluorescence methods. While CIS administration remarkably elevated reactive oxygen species, MDA, and NO levels in brain tissue compared to the control, tGSH, GPx, SOD and CAT levels were significantly decreased. Also, it has been detected that TNF-α, IL-1β and IL-6 obtained in CIS-treated groups increased as well as IL-10 decreased, thereby elevating the inflammatory response. In addition, 8-OHdG and caspase-3 immunoreactivity in neurons increased with CIS administration. Treatment with tangeretin ameliorated the deterioration in oxidant/antioxidant status, overpowered neuroinflammation and ameliorated neurotoxicity-induced apoptosis. This study shows that tangeretin has beneficial effects on CIS-induced neurodegeneration. Possible mechanisms underlying these beneficial effects include the antioxidant and anti-inflammatory properties of tangeretin.

N-Acetylcysteine Attenuates Cisplatin Toxicity in the Cerebrum and Lung of Young Rats with Artificially Induced Protein Deficiency

Neurotoxicity is a major obstacle in the effectiveness of Cisplatin in cancer chemotherapy. In this process, oxidative stress and inflammation are considered to be the main mechanisms involved in brain and lung toxicity. The aim of the present work was to study the influence of the amount of protein on some oxidative parameters in the brain and lungs of rats treated with Cisplatin (CP) and N-Acetylcysteine (NAC) as neuroprotectors. Four groups of Wistar rats, each containing six animals, were fed with a protein diet at 7% for 15 days. Thereafter, the groups were given either a unique dose of CP® 5 mg/kg or NAC® 5 mg/kg as follows: group 1 (control), NaCl 0.9% vehicle; group 2, CP; group 3, NAC; and group 4, NAC + CP. The animals were sacrificed immediately after the treatments. Blood samples were collected upon sacrifice and used to measure blood triglycerides and glucose. The brain and lungs of each animal were obtained and used to assay lipid peroxidation (TBARS), glutathione (GSH), serotonin metabolite (5-HIAA), catalase, and the activity of Ca+2, and Mg+2 ATPase using validated methods. TBARS, H2O2, and GSH were found to be significantly decreased in the cortex and cerebellum/medulla oblongata of the groups treated with CP and NAC. The total ATPase showed a significant increase in the lung and cerebellum/medulla oblongata, while 5-HIAA showed the same tendency in the cortex of the same group of animals. The increase in 5-HIAA and ATPase during NAC and CP administration resulted in brain protection. This effect could be even more powerful when membrane fluidity is increased, thus proving the efficacy of combined NAC and CP drug therapy, which appears to be a promising strategy for future chemotherapy in malnourished patients.

Inhibition of Apoptosis in a Model of Ischemic Stroke Leads to Enhanced Cell Survival, Endogenous Neural Precursor Cell Activation and Improved Functional Outcomes

Stroke results in neuronal cell death, which causes long-term disabilities in adults. Treatment options are limited and rely on a narrow window of opportunity. Apoptosis inhibitors demonstrate efficacy in improving neuronal cell survival in animal models of stroke. However, many inhibitors non-specifically target apoptosis pathways and high doses are needed for treatment. We explored the use of a novel caspase-3/7 inhibitor, New World Laboratories (NWL) 283, with a lower IC50 than current caspase-3/7 inhibitors. We performed in vitro and in vivo assays to determine the efficacy of NWL283 in modulating cell death in a preclinical model of stroke. In vitro and in vivo assays show that NWL283 enhances cell survival of neural precursor cells. Delivery of NWL283 following stroke enhances endogenous NPC migration and leads to increased neurogenesis in the stroke-injured cortex. Furthermore, acute NWL283 administration is neuroprotective at the stroke injury site, decreasing neuronal cell death and reducing microglia activation. Coincident with NWL283 delivery for 8 days, stroke-injured mice exhibited improved functional outcomes that persisted following cessation of the drug. Therefore, we propose that NWL283 is a promising therapeutic warranting further investigation to enhance stroke recovery.

HIF-1α promotes kidney organoid vascularization and applications in disease modeling

BACKGROUND

Kidney organoids derived from human pluripotent stem cells (HiPSCs) hold huge applications for drug screening, disease modeling, and cell transplanting therapy. However, these applications are limited since kidney organoid cannot maintain complete morphology and function like human kidney. Kidney organoids are not well differentiated since the core of the organoid lacked oxygen, nutrition, and vasculature, which creates essential niches. Hypoxia-inducible factor-1 α (HIF-1α) serves as a critical regulator in vascularization and cell survival under hypoxia environment. Less is known about the role of HIF-1α in kidney organoids in this regard. This study tried to investigate the effect of HIF-1α in kidney organoid vascularization and related disease modeling.

METHODS

For the vascularization study, kidney organoids were generated from human induced pluripotent stem cells. We overexpressed HIF-1α via plasmid transfection or treated DMOG (Dimethyloxallyl Glycine, an agent for HIF-1α stabilization and accumulation) in kidney progenitor cells to detect the endothelium. For the disease modeling study, we treated kidney organoid with cisplatin under hypoxia environment, with additional HIF-1α transfection.

RESULT

HIF-1α overexpression elicited kidney organoid vascularization. The endothelial cells and angiotool analysis parameters were increased in HIF-1α plasmid-transfected and DMOG-treated organoids. These angiogenesis processes were partially blocked by VEGFR inhibitors, semaxanib or axitinib. Cisplatin-induced kidney injury (Cleaved caspase 3) was protected by HIF-1α through the upregulation of CD31 and SOD2.

CONCLUSION

We demonstrated that HIF-1α elicited the process of kidney organoid vascularization and protected against cisplatin-induced kidney organoid injury in hypoxia environment.

Neuroprotective effect of lansoprazole against cisplatin-induced brain toxicity: Role of Nrf2/ARE and Akt/P53 signaling pathways

Cisplatin is a chemotherapeutic agent usually used in treating different patterns of malignancies. One of the significant apparent complications of cisplatin chemotherapy is brain toxicity. The present study was conducted to evaluate the protective effects of lansoprazole on cisplatin-induced cortical intoxication. Thirty-two rats were allocated into four groups (8 rats/group); group I: received only a vehicle for 10 days, group II: lansoprazole was administered (50 mg/kg) via oral gavage for 10 days, group III: On 5th day of the experiment, rats were given cisplatin (10 mg/kg) i.p. once to induce cortical injury. Group IV: rats were given lansoprazole for 5 days before cisplatin and 5 days afterward. Lansoprazole administration significantly improved cisplatin-induced behavioral changes, as evidenced by decreasing the immobility time in forced swimming and open field tests. Besides, lansoprazole improved cortical histological changes, restored cortical redox balance, enhanced Nrf2/ARE expression, cisplatin-induced neuronal apoptosis, and dampened cisplatin inflammation. In addition, lansoprazole modulated cortical Akt/p53 signal. The present work was the first to show that lansoprazole co-administration reduced cortical toxicity in cisplatin-treated rats via multiple signaling pathways. The current findings provided crucial information for developing novel protective strategies to reduce cisplatin cortical toxicity.

Scutebarbatine A induces ROS-mediated DNA damage and apoptosis in breast cancer cells by modulating MAPK and EGFR/Akt signaling pathway

Scutebarbatine A (SBT-A), a diterpenoid alkaloid, has exerted cytotoxicity on hepatocellular carcinoma cells in our previous works. Here, the antitumor activity of SBT-A in breast cancer cells and the underlying mechanism were explored. The anti-proliferative effect of SBT-A was measured by trypan blue staining, 5-ethynyl-2'-deoxyuridine (EdU) incorporation and colony formation assay. DNA double-strand breaks (DSBs) were evaluated by observing the nuclear focus formation of γ-H2AX. Cell cycle distribution was assessed by flow cytometry. Apoptosis was determined by a TUNEL assay. Intracellular reactive oxygen species (ROS) generation and superoxide production were measured with 2', 7'-dichlorofluorescein diacetate (DCFH-DA) and dihydroethidium (DHE) staining, respectively. The results indicated that SBT-A showed a dose-dependent cytotoxic effect against breast cancer cells while revealing less toxicity toward MCF-10A breast epithelial cells. Moreover, SBT-A remarkably induced DNA damage, cell cycle arrest and apoptosis in both MDA-MB-231 and MCF-7 cells. SBT-A treatment increased the levels of ROS and cytosolic superoxide production. Pretreatment with N-acetyl cysteine (NAC), a ROS scavenger, was sufficient to block viability reduction, DNA damage, apoptosis and endoplasmic reticulum (ER) stress caused by SBT-A. By exposure to SBT-A, the phosphorylation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK) was upregulated, while the phosphorylation of extracellular signal-regulated kinase (ERK) was downregulated. In addition, SBT-A inhibited the EGFR signaling pathway by decreasing EGFR expression and phosphorylation of Akt and p70S6K. As mentioned above, SBT-A has a potent inhibitory effect on breast cancer cells through induction of DNA damage, apoptosis and ER stress via ROS generation and modulation of MAPK and EGFR/Akt signaling pathway.

Alleviation of cisplatin-induced neuropathic pain, neuronal apoptosis, and systemic inflammation in mice by rapamycin

Platinum-based chemotherapeutic treatment of cancer patients is associated with debilitating adverse effects. Several adverse effects have been well investigated, and can be managed satisfactorily, but chemotherapy-induced peripheral neuropathy (CIPN) remains poorly treated. Our primary aim in this study was to investigate the neuroprotective effect of the immunomodulatory drug rapamycin in the mitigation of cisplatin-induced neurotoxicity. Pain assays were performed in vivo to determine whether rapamycin would prevent or significantly decrease cisplatin-induced neurotoxicity in adult male Balb/c mice. Neuropathic pain induced by both chronic and acute exposure to cisplatin was measured by hot plate assay, cold plate assay, tail-flick test, and plantar test. Rapamycin co-treatment resulted in significant reduction in cisplatin-induced nociceptive-like symptoms. To understand the underlying mechanisms behind rapamycin-mediated neuroprotection, we investigated its effect on certain inflammatory mediators implicated in the propagation of chemotherapy-induced neurotoxicity. Interestingly, cisplatin was found to significantly increase peripheral IL-17A expression and CD8- T cells, which were remarkably reversed by the pre-treatment of mice with rapamycin. In addition, rapamycin reduced the cisplatin-induced neuronal apoptosis marked by decreased neuronal caspase-3 activity. The rapamycin neuroprotective effect was also associated with reversal of the changes in protein expression of p21^Cip1, p53, and PUMA. Collectively, rapamycin alleviated some features of cisplatin-induced neurotoxicity in mice and can be further investigated for the treatment of cisplatin-induced peripheral neuropathy.