Attenuation of cyclophosphamide-induced pulmonary toxicity in Swiss albino mice by naphthalimide-based organoselenium compound 2-(5-selenocyanatopentyl)-benzo[de]isoquinoline 1,3-dione

Redox Interactions in Chemo/Radiation Therapy-induced Lung Toxicity; Mechanisms and Therapy Perspectives

Lung toxicity is a key limiting factor for cancer therapy, especially lung, breast, and esophageal malignancies. Radiotherapy for chest and breast malignancies can cause lung injury. However, systemic cancer therapy with chemotherapy may also induce lung pneumonitis and fibrosis. Radiotherapy produces reactive oxygen species (ROS) directly via interacting with water molecules within cells. However, radiation and other therapy modalities may induce the endogenous generation of ROS and nitric oxide (NO) by immune cells and some nonimmune cells such as fibroblasts and endothelial cells. There are several ROS generating enzymes within lung tissue. NADPH Oxidase enzymes, cyclooxygenase-2 (COX-2), dual oxidases (DUOX1 and DUOX2), and the cellular respiratory system in the mitochondria are the main sources of ROS production following exposure of the lung to anticancer agents. Furthermore, inducible nitric oxide synthase (iNOS) has a key role in the generation of NO following radiotherapy or chemotherapy. Continuous generation of ROS and NO by endothelial cells, fibroblasts, macrophages, and lymphocytes causes apoptosis, necrosis, and senescence, which lead to the release of inflammatory and pro-fibrosis cytokines. This review discusses the cellular and molecular mechanisms of redox-induced lung injury following cancer therapy and proposes some targets and perspectives to alleviate lung toxicity.

Methamphetamine induced neurotoxic diseases, molecular mechanism, and current treatment strategies

Methamphetamine (MA) is a extremely addictive psychostimulant drug with a significant abuse potential. Long-term MA exposure can induce neurotoxic effects through oxidative stress, mitochondrial functional impairment, endoplasmic reticulum stress, the activation of astrocytes and microglial cells, axonal transport barriers, autophagy, and apoptosis. However, the molecular and cellular mechanisms underlying MA-induced neurotoxicity remain unclear. MA abuse increases the chances of developing neurotoxic conditions such as Parkinson's disease (PD), Alzheimer's disease (AD) and other neurotoxic diseases. MA increases the risk of PD by increasing the expression of alpha-synuclein (ASYN). Furthermore, MA abuse is linked to high chances of developing AD and subsequent neurodegeneration due to biological variations in the brain region or genetic and epigenetic variations. To date, there is no Food and Drug Administration (FDA)-approved therapy for MA-induced neurotoxicity, although many studies are being conducted to develop effective therapeutic strategies. Most current studies are now focused on developing therapies to diminish the neurotoxic effects of MA, based on the underlying mechanism of neurotoxicity. This review article highlights current research on several therapeutic techniques targeting multiple pathways to reduce the neurotoxic effects of MA in the brain, as well as the putative mechanism of MA-induced neurotoxicity.

Antiproliferative, Apoptotic Effects and Suppression of Oxidative Stress of Quercetin against Induced Toxicity in Lung Cancer Cells of Rats: In vitro and In vivo Study

In the present study, quercetin was examined against lung human cancer cells using A549 and H69 cancer cell lines in addition to normal non cancer cells (W138). Two genes Bax and Bcl-2 that play an important role in apoptosis pathways were investigated. Also Immunohistochemical study for caspase-3 which is considered as indicator for apoptosis was performed. Quercetin showed good anti proliferative activity against tested lung cancer cell lines, IC50 values on A549 are 8.65, 7.96 and 5.14 µg/ml at 24, 48 and 72h respectively. Also significant effects of quercetin on Bax, Bcl-2 and caspase-3 were observed, that can prove its ability to induce apoptosis. On the other hand quercetin showed good therapeutic effects against cyclophosphamide induced lung toxicity that were observed in the histopathology study. In vitro studies were also performed such as cell cycle analysis through flowcytometry. The obtained results from all these performed analysis proved that quercetin can induce apoptosis in human lung cancer cells, additionally quercetin showed ability to reduce MDA and increase SOD and GSHP levels which indicates its ability in suppressing oxidative stress, Quercetin has played a therapeutic role in cyclophosphamide induced lung toxicity as it has improved restoring of the damaged lung tissue as discussed in this research work.

Psychoactive Drugs-From Chemical Structure to Oxidative Stress Related to Dopaminergic Neurotransmission. A Review

Nowadays, more and more young people want to experience illegal, psychoactive substances, without knowing the risks of exposure. Besides affecting social life, psychoactive substances also have an important effect on consumer health. We summarized and analyzed the published literature data with reference to the mechanism of free radical generation and the link between chemical structure and oxidative stress related to dopaminergic neurotransmission. This review presents data on the physicochemical properties, on the ability to cross the blood brain barrier, the chemical structure activity relationship (SAR), and possible mechanisms by which neuronal injuries occur due to oxidative stress as a result of drug abuse such as "bath salts", amphetamines, or cocaine. The mechanisms of action of ingested compounds or their metabolites involve intermediate steps in which free radicals are generated. The brain is strongly affected by the consumption of such substances, facilitating the induction of neurodegenerative diseases. It can be concluded that neurotoxicity is associated with drug abuse. Dependence and oxidative stress are linked to inhibition of neurogenesis and the onset of neuronal death. Understanding the pathological mechanisms following oxidative attack can be a starting point in the development of new therapeutic targets.

The role of selenium in cell survival and its correlation with protective effects against cardiovascular disease: A literature review

Selenium is a trace element that provides protection against cellular damage and death. Previous research using several types of cells identified anti-oxidant, anti-inflammatory, and anti-apoptotic effects for selenium. One of the diseases related to selenium is cardiovascular disease, as low selenium intake has been linked to cardiomyopathy. However, the mechanism of the cardioprotective effects of selenium is not thoroughly understood. Several studies supported the possible effects of selenium on heart cell survival. In this review, we analyzed recent research (2015-2020) on the roles and mechanism of action of selenium in cell survival and its cardioprotective effects. Furthermore, the prevention of apoptosis through both intrinsic and extrinsic pathways is discussed in this review. Signalling pathways that regulate cell survival such as the p-AMPK, poly (ADP-ribose) polymerase-1, nuclear factor-erythroid 2-related factor-2, AKT/PI3K, and STAT pathways are involved in the protective effects of selenium. In addition, signaling pathways that affect heart cell survival include the AKT and STAT pathways. It also affects autophagy through the PPAR-γ pathway. These findings should facilitate further research on the cardioprotective effects of selenium.

Antioxidant and Anti-Inflammatory Effects of Diallyl Disulfide on Hepatotoxicity Induced by Cyclophosphamide in Rats

Diallyl disulfide (DADS) is a garlic-derived organo-sulfur compound. This study was carried out to investigate the protective potential, antioxidant, and anti-inflammatory effects of this compound against cyclophosphamide (CP)-induced hepatotoxicity in rats. A single intraperitoneal dose of CP (200 mg/kg) resulted in a significant disturbance in hepatic function and oxidative stress, as well as inflammatory biomarkers. In addition, histopathological examination showed distinct changes and increased expression of proliferating cell nuclear antigen in hepatocytes. On the other hand, daily oral preadministration of DADS (200 mg/kg) for 10 days before the CP dose effectively attenuated the hepatotoxicity caused by CP administration as confirmed by significant amelioration of the aforementioned parameters in rat’s liver. It could be concluded that administration of DADS can diminish CP-induced hepatotoxicity through concurrent upregulation of antioxidant and anti-inflammatory responses that denote its possible potential clinical application against side effects of the CP drug.

Biosynthesis of selenium nanoparticles and their protective, antioxidative effects in streptozotocin induced diabetic rats

Green synthesis of selenium nanoparticles (Se NPs) was performed by mixing Hibiscus sabdariffa (roselle plant) leaf extract with the solution of selenious acid (H₂SeO₃) under continuous stirring conditions resulting the roselle plant secondary metabolites conjugated Se NPs. The existence of functional groups of roselle plant secondary metabolites on the surface of prepared Se NPs was confirmed by Fourier transform infrared spectroscopy (FTIR). The formation of crystalline nanoparticles with anisotropic shape was confirmed by transmission electron microscopy (TEM) images. Furthermore, we also studied anti-oxidative and protective effects of Se NPs in streptozotocin (STZ) induced diabetes rats. These STZ induced diabetic rats were daily exposed to Se NPs or/and insulin treatment and the effect of Se NPs on the factors correlated to oxidative damage in the rat testes were evaluated. The biochemical studies showed that the Se NPs are capable to enhance the serum testosterone reduction caused due to STZ induced diabetes. In addition, Se NPs can significantly reduce the oxidative stress indicators of the testicular tissue such as nitric oxide and lipid peroxidation. However, the treatment of Se NPs on the STZ induced diabetic rats increased the activities of antioxidant enzyme as well as the glutathione content in testicular tissues. Furthermore, microscopic studies revealed that the Se NPs are capable of preventing the histological damage in the testes of STZ induced diabetic rats. Altogether, these results explained the possible effects of Se NPs in attenuating oxidative damage induced by diabetes, especially in the testicular tissue.

A general covalent binding model between cytotoxic selenocompounds and albumin revealed by mass spectrometry and X-ray absorption spectroscopy

Selenocompounds (SeCs) are promising therapeutic agents for a wide range of diseases including cancer. The treatment results are heterogeneous and dependent on both the chemical species and the concentration of SeCs. Moreover, the mechanisms of action are poorly revealed, which most probably is due to the detection methods where the quantification is based on the total selenium as an element. To understand the mechanisms underlying the heterogeneous cytotoxicity of SeCs and to determine their pharmacokinetics, we investigated selenium speciation of six SeCs representing different categories using liquid chromatography-mass spectrometry (LC-MS) and X-ray absorption spectroscopy (XAS) and the cytotoxicity using leukemic cells. SeCs cytotoxicity was correlated with albumin binding degree as revealed by LC-MS and XAS. Further analysis corroborated the covalent binding between selenol intermediates of SeCs and albumin thiols. On basis of the Se-S model, pharmacokinetic properties of four SeCs were for the first time profiled. In summary, we have shown that cytotoxic SeCs could spontaneously transform into selenol intermediates that immediately react with albumin thiols through Se-S bond. The heterogeneous albumin binding degree may predict the variability in cytotoxicity. The present knowledge will also guide further kinetic and mechanistic investigations in both experimental and clinical settings.

Curcumin Prevents Cyclophosphamide-Induced Lung Injury in Rats by Suppressing Oxidative Stress and Apoptosis

Curcumin (CUR) has been used since ancient times to treat several ailments as it possesses many pharmacological activities. This study intended to explore the mechanism underlying the protective effects of CUR in remodeling oxidative stress and apoptotic signals in cyclophosphamide (CP)-induced pulmonary injury in albino rats. CUR was administered at a dose of 300 mg/kg/day for 7 days and on the seventh day a single dose of CP (200 mg/kg) was given. Histopathological and ultrastructural examinations of CP-intoxicated rats showed complete alveolar obstruction, thickened inter-alveolar septa, enlarged blood vessels, severe inflammatory edema with pyknotic nuclei, and disappearance of cytoplasmic organelles. Significant increases in caspase-3, malondialdehyde (MDA), and protein carbonyl (PCO) and significant decreases in superoxide dismutase (SOD) and glutathione peroxidase (GPx) were observed. In contrast, rats that received CUR showed clear and empty lumina with single row of pneumocytes, disappearance of edema, and no interstitial electron dense bodies in rats’ lung tissues. Additionally, CUR significantly reduced caspase-3, MDA, and PCO and increased SOD and GPx. In conclusion, these findings revealed the protective effects of CUR against CP-induced pulmonary injury in rats through suppressing oxidative damage and apoptosis.

The Main Molecular Mechanisms Underlying Methamphetamine- Induced Neurotoxicity and Implications for Pharmacological Treatment

Methamphetamine (METH) is a popular new-type psychostimulant drug with complicated neurotoxicity. In spite of mounting evidence on METH-induced damage of neural cell, the accurate mechanism of toxic effect of the drug on central nervous system (CNS) has not yet been completely deciphered. Besides, effective treatment strategies toward METH neurotoxicity remain scarce and more efficacious drugs are to be developed. In this review, we summarize cellular and molecular bases that might contribute to METH-elicited neurotoxicity, which mainly include oxidative stress, excitotoxicity, and neuroinflammation. We also discuss some drugs that protect neural cells suffering from METH-induced neurotoxic consequences. We hope more in-depth investigations of exact details that how METH produces toxicity in CNS could be carried out in future and the development of new drugs as natural compounds and immunotherapies, including clinic trials, are expected.

Selenocompounds in Cancer Therapy: An Overview

In vitro and in vivo experimental models clearly demonstrate the efficacy of Se compounds as anticancer agents, contingent upon chemical structures and concentrations of test molecules, as well as on the experimental model under investigation that together influence cellular availability of compounds, their molecular dynamics and mechanism of action. The latter includes direct and indirect redox effects on cellular targets by the activation and altered compartmentalization of molecular oxygen, and the interaction with protein thiols and Se proteins. As such, Se compounds interfere with the redox homeostasis and signaling of cancer cells to produce anticancer effects that include alterations in key regulatory elements of energy metabolism and cell cycle checkpoints that ultimately influence differentiation, proliferation, senescence, and death pathways. Cys-containing proteins and Se proteins involved in the response to Se compounds as sensors and transducers of anticancer signals, i.e., the pharmacoproteome of Se compounds, are described and include critical elements in the different phases of cancer onset and progression from initiation and escape of immune surveillance to tumor growth, angiogenesis, and metastasis. The efficacy and mode of action on these compounds vary depending on the inorganic and organic form of Se used as either supplement or pharmacological agent. In this regard, differences in experimental/clinical protocols provide options for either chemoprevention or therapy in different human cancers.

Chemoprotective and chemosensitizing properties of selenium nanoparticle (Nano-Se) during adjuvant therapy with cyclophosphamide in tumor-bearing mice

Cyclophosphamide (CP) is one of the widely used anticancer agents; however, it has serious deleterious effects on normal host cells due to its nonspecific action. The essential trace element Selenium (Se) is suggested to have chemopreventive and chemotherapeutic efficacy and currently used in pharmaceutical formulations. Previous report had shown Nano-Se could protect CP-induced hepatotoxicity and genotoxicity in normal Swiss albino mice; however, its role in cancer management is still not clear. The aim of present study is to investigate the chemoprotective efficacy of Nano-Se against CP-induced toxicity as well as its chemoenhancing capability when used along with CP in Swiss albino mice against Ehrlich's ascites carcinoma (EAC) cells. CP was administered (25 mg/kg b.w., i.p.) and Nano-Se was given (2 mg Se/kg b.w., p.o.) in concomitant and pretreatment schedule. Increase levels of serum hepatic marker, hepatic lipid peroxidation, DNA damage, and chromosomal aberration in CP-treated mice were significantly (P < 0.05) reversed by Nano-Se. The lowered status of various antioxidant enzymes in tumor-bearing mice after CP treatment was also effectively increased by Nano-Se. Administration of Nano-Se along with CP caused a significant reduction in tumor volume, packed cell volume, viable tumor cell count, and increased the survivability of the tumor-bearing hosts. The results suggest that Nano-Se exhibits significant antitumor and antioxidant effects in EAC-bearing mice. The potential for Nano-Se to ameliorate the CP-evoked toxicity as well as to improve the chemotherapeutic effect could have beneficial implications for patients undergoing chemotherapy with CP.

Identification of selenocompounds with promising properties to reverse cancer multidrug resistance

In previous studies, 56 novel selenoesters and one cyclic selenoanhydride with chemopreventive, antiproliferative and cytotoxic activity were described. Herein, the selenoanhydride and selected selenoesters were evaluated for their ability to reverse the cancer multidrug resistance (MDR) using the ABCB1 efflux pump inhibition assay in mouse MDR T-lymphoma cells. Results showed that the selenoanhydride (1) and the selenoesters with ketone terminal fragments (9-11) exerted (1.7-3.6)-fold stronger efflux pump inhibitory action than the reference verapamil. In addition, those four derivatives triggered apoptotic events in more than 80% of the examined MDR mouse cells.

Prevention of cyclophosphamide-induced hepatotoxicity and genotoxicity: Effect of an L-cysteine based oxovanadium(IV) complex on oxidative stress and DNA damage

Vanadium has been emerged as a promising agent owing to its ability to prevent several types of cancer. This study was aimed to investigate the protective role of an organovanadium complex, viz., oxovanadium(IV)-L-cysteine methyl ester (VC-IV) against cyclophosphamide (CP)-induced hepatotoxicity and genotoxicity in mice. Oral administration of VC-IV quite effectively ameliorated CP-induced histopathological lesions and reduced levels of alanine transaminase, aspartate transaminase and alkaline phosphatase. In addition, VC-IV significantly attenuated CP-induced oxidative stress in the liver as evident from levels of reactive oxygen species, nitric oxide and lipid peroxidation. Restoration of glutathione level and activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase) were also observed upon VC-IV administration. Moreover, VC-IV significantly mitigated CP-induced chromosomal aberrations, micronuclei formation, DNA fragmentation and apoptosis in bone marrow cells and DNA damage in lymphocytes. The present study showed that VC-IV could provide adequate protection against CP-induced hepatotoxicity and genotoxicity in vivo.