Selenium attenuates docetaxel-induced apoptosis and mitochondrial oxidative stress in kidney cells

Dietary selenomethionine reduced oxidative stress by resisting METTL3-mediated m6A methylation level of Nrf2 to ameliorate LPS-induced liver necroptosis in laying hens

Selenomethionine (SeMet) as the main form of daily dietary selenium, occupies essential roles in providing antioxidant and anti-inflammatory properties, which alleviates inflammatory liver damage. N6-methyladenosine (m6A) is one of the most prevalent and abundant internal transcriptional modifications that regulate gene expression. To investigate the protective mechanism of SeMet on liver injury and the regulatory effect of m6A methylation modification, we established the model by supplementing dietary SeMet, and LPS as stimulus in laying hens. LMH cells were intervened with SeMet (0.075 µM) and/or LPS (60 µg/mL). Subsequently, histopathology and ultrastructure of liver were observed. Western Blot, qRT-PCR, colorimetry, MeRIP-qPCR, fluorescent probe staining and AO/EB were used to detect total m6A methylation level, m6A methylation level of Nrf2, ROS, inflammatory and necroptosis factors. Studies showed that SeMet suppressed LPS-induced upregulation of total m6A methylation levels and METTL3 expression. Interestingly, SeMet reduced the m6A methylation level of Nrf2, activated antioxidant pathways and alleviated oxidative stress. LMH cells were transfected with 50 µm siMETTL3. SeMet/SiMETTL3 reversed the LPS-induced reduction in Nrf2 mRNA stability, slowed down its degradation rate. Moreover, LPS induced oxidative stress, led to necroptosis and activated NF-κB to promote the expression of inflammatory factors. SeMet/SiMETTL3 alleviated LPS-induced necroptosis and inflammation. Altogether, SeMet enhanced antioxidant and anti-inflammatory capacity by reducing METTL3-mediated m6A methylation levels of Nrf2, ultimately alleviating liver damage. Our findings provided new insights and therapeutic target for the practical application of dietary SeMet in the treatment and prevention of liver inflammation, and supplied a reference for comparative medicine.

Role of TRPM2 in brain tumours and potential as a drug target

Ion channels are ubiquitously expressed in almost all living cells, and are the third-largest category of drug targets, following enzymes and receptors. The transient receptor potential melastatin (TRPM) subfamily of ion channels are important to cell function and survival. Studies have shown upregulation of the TRPM family of ion channels in various brain tumours. Gliomas are the most prevalent form of primary malignant brain tumours with no effective treatment; thus, drug development is eagerly needed. TRPM2 is an essential ion channel for cell function and has important roles in oxidative stress and inflammation. In response to oxidative stress, ADP-ribose (ADPR) is produced, and in turn activates TRPM2 by binding to the NUDT9-H domain on the C-terminal. TRPM2 has been implicated in various cancers and is significantly upregulated in brain tumours. This article reviews the current understanding of TRPM2 in the context of brain tumours and overviews the effects of potential drug therapies targeting TRPM2 including hydrogen peroxide (H2O2), curcumin, docetaxel and selenium, paclitaxel and resveratrol, and botulinum toxin. It is long withstanding knowledge that gliomas are difficult to treat effectively, therefore investigating TRPM2 as a potential therapeutic target for brain tumours may be of considerable interest in the fields of ion channels and pharmacology.

The involvement of TRPM2 on the MPP+-induced oxidative neurotoxicity and apoptosis in hippocampal neurons from neonatal mice: protective role of resveratrol

Parkinson's disease (PD) is an age-related chronic neurodegenerative disease. Although PD is known to be a result of damage to hippocampal neurons, its molecular mechanism has yet to be completely clarified. The neurodegeneration in hippocampal neurons has been suggested to include excessive production of reactive oxygen species (ROS). Mitochondrial dysfunction and disruption of intracellular Ca²⁺ homeostasis play the most important role in the increase in ROS production for the cells. Remarkably, it is stated in the literature that especially the change of Ca²⁺ homeostasis triggers neuronal degeneration. TRPM2 is a unique calcium-permeable nonselective cation channel, and densest in the numberless neuronal population. The current study aims to elucidate the effect of antioxidant resveratrol (Resv) on TRPM2-mediated oxidative stress (OS) induced by 1-methyl-4-phenylpyridinium (MPP) exposure in the primary mouse hippocampal neurons. The neurons were divided into four groups as Control, Resv , MPP, and MPP+ Resv. In the current results, the activation of TRPM2 was observed in primary hippocampal neurons with MPP incubation. TRPM2 channel expression levels in the MPP group increased in hippocampal neurons after MPP exposure. In addition, intracellular free Ca²⁺ concentration and TRPM2 channel currents were highest in MPP groups, although they were decreased by the Resv treatment. In addition, mitochondrial membrane depolarization, ROS, caspase-3, caspase-9, and apoptosis values induced by MPP decreased with resveratrol treatment. In conclusion, in our study, we observed that the dysregulation of OS-induced TRPM2 channel activation in hippocampal neurons exposed to MPP caused apoptotic cell death in neurons, while the use of resveratrol had a protective effect by reducing OS resources in the environment.

The Protective Effect of Selenium on T-2-Induced Nephrotoxicity Is Related to the Inhibition of ROS-Mediated Apoptosis in Mice Kidney

T-2 toxin is produced by the Fusarium genus. Ingestion of food or feed contaminated by T-2 toxin will cause damage to kidney. Selenium (Se), an essential trace element, showed the significant protective effects against kidney and renal cell damage induced by toxic substances. To explore the protective effects and mechanisms of Se against T-2-induced renal lesions, forty-eight male Kunming mice were exposed to T-2 toxin (1.0 mg/kg) and/or Se (0.2 mg/kg) for 28 days. In this study, we found that Se alleviated T-2-induced nephrotoxicity, presenting as increasing the body weight and kidney coefficient, relieving the renal structure injury, decreasing the contents of renal function-related biomarkers, decreasing the levels of reactive oxygen species (ROS), and increasing the mitochondrial membrane potential in T-2 toxin-treated mice. In addition, inhibition of renal cell apoptosis by Se was associated with blocking the mitochondrial pathway in T-2 toxin-treated mice, presenting as decreasing the protein expression of cytochrome-c, activities of caspase-3/9, as well as regulating the protein and mRNA expressions of Bax and Bcl-2. These results documented that the alleviating effect of Se on T-2-induced nephrotoxicity is related to the inhibition of ROS-mediated renal apoptosis.

Brazilian green propolis: A novel tool to improve the cytotoxic and immunomodulatory action of docetaxel on MCF-7 breast cancer cells and on women monocyte

Docetaxel (DTX) is used against breast cancer despite its side effects such as toxicity and immunosuppression. Here we investigated the cytotoxic and immunomodulatory effects of the ethanol solution extract of propolis (EEP) in combination with DTX on MCF-7 breast cancer cells and on women's monocyte. The cytotoxic potential of EEP + DTX was assessed by MTT assay and the type of tumor cell death was evaluated by flow cytometry. The effects of EEP + DTX on the migration and invasion of MCF-7 cells were analyzed. Cytokine production by monocytes was assessed by ELISA and the expression of cell surface markers was evaluated by flow cytometry. We also assessed the fungicidal activity of monocytes against Candida albicans and the generation of reactive oxygen species (ROS). Finally, the impact of the supernatants of treated monocytes in the viability, migration, and invasiveness of tumor cells was assessed. EEP enhanced the cytotoxicity of DTX alone against MCF-7 cells by inducing necrosis and inhibiting their migratory ability. EEP + DTX exerted no cytotoxic effects on monocytes and stimulated HLA-DR expression, TNF-α, and IL-6 production, exerted an immunorestorative action in the fungicidal activity, and reduced the oxidative stress. Our findings have practical implications and reveal new insights for complementary medicine.

Renal Safety of [177Lu]Lu-PSMA-617 Radioligand Therapy in Patients with Compromised Baseline Kidney Function

Background: Radioligand therapy (RLT) targeting prostate-specific membrane antigen (PSMA) is an effective antitumor-treatment in metastatic castration-resistant prostate carcinoma (mCRPC). Concerns of potential nephrotoxicity are based on renal tubular PSMA expression and the resulting radiopharmaceutical retention during RLT, but data confirming clinically significant renal toxicity are still lacking. In this study, patients with significantly impaired baseline kidney function before initiation of therapy were investigated for treatment-associated nephrotoxicity and the potential relationship with administered activities of [¹⁷⁷Lu]Lu-PSMA-617. Methods: Twenty-two mCRPC patients with impaired renal function (glomerular filtration rate (GFR) ≤ 60 mL/min) who received more than two cycles of [¹⁷⁷Lu]Lu-PSMA-617 RLT (median 5 cycles and median 6-week time interval between consecutive cycles) were analyzed in this study. Patients were treated within a prospective patient registry (REALITY Study, NCT04833517). Cumulative administered activities ranged from 17.1 to 85.6 GBq with a median activity of 6.5 GBq per cycle. Renal function was closely monitored during and after PSMA-RLT. Results: Mean pre-treatment GFR was 45.0 ± 10.7 mL/min. After two (22/22 patients), four (20/22 patients), and six cycles (10/22 patients) of RLT, a significant increase of GFR was noted (each p < 0.05). End-of-treatment GFR (54.1 ± 16.7 mL/min) was significantly higher than baseline GFR (p = 0.016). Only one patient experienced deterioration of renal function (change of CTCAE grade 2 to 3). The remaining patients showed no significant reduction of GFR, including follow-up assessments (6, 9, and 12 months), and even showed improved (10/22 patients) or unchanged (11/22 patients) CTCAE-based renal impairment grades during and after the end of PSMA-RLT. No significant correlation between the change in GFR and per-cycle (p = 0.605) or cumulative (p = 0.132) administered activities were found. Conclusions: As pre-treatment chronic kidney failure did not lead to detectable RLT-induced deterioration of renal function in our study, the nephrotoxic potential of [¹⁷⁷Lu]Lu-PSMA-617 RLT may be overestimated and not of clinical priority in the setting of palliative treatment in mCRPC. We suggest not to categorically exclude patients from enrolment to PSMA-RLT due to renal impairment.

Dietary selenomethionine ameliorates lipopolysaccharide-induced renal inflammatory injury in broilers via regulating the PI3K/AKT pathway to inhibit necroptosis

Selenomethionine (SeMet) has antioxidant and anti-inflammatory effects, as a widely used organic Se source in food supplements, and its inhibitory effect on the prevention and treatment of renal inflammatory injury is unclear. Here, in order to explore the protective effect of SeMet on kidney tissue of broilers and determine its potential molecular mechanism, we took broilers as the research object, lipopolysaccharide (LPS) was used as the source of stimulation, and the model was established by adding SeMet to the diet. The histopathological observation indicated that SeMet alleviated the LPS-induced characteristic changes of renal inflammatory injury. Besides, SeMet inhibited LPS-induced PI3K, AKT, caspase 8 and IκB-α downregulation, the necroptosis marker genes (FADD, RIP1, RIP3, MLKL and TNF-α), pro-inflammatory factors (NF-κB, PTGEs, COX-2, iNOS, IL-1β and IL-6) and HSP60, HSP70 and HSP90 overexpression. We concluded that SeMet ameliorates LPS-induced renal inflammatory injury in broilers by inhibiting necroptosis via the regulation of the PI3K/Akt pathway. Thus, we speculated that dietary SeMet may be a potential new strategy for the treatment of renal injury.

Protective effects of selenium in tacrolimus-induced lung toxicity: potential role of heme oxygenase 1

The present study aimed to evaluate the protective effects of selenium (Sel) administration against tacrolimus (Tac) - induced lung toxicity and to assess the relation between heme oxygenase 1 (HO-1) and these effects. The study was conducted on 36 Wistar male albino rats equally divided into four groups: (i) normal control; (ii) Sel (0.1 mg/kg per day p.o. for four weeks); (iii) TAC 3 mg/mL as single oral dose on 27th day; and (iv) Tac + Sel. Lung tissues, lung homogenate, and bronchoalveolar lavage of the sacrificed animals were investigated biochemically and histopathologically, by immunohistochemistry or by PCR. The Tac group showed significantly lower expression of HO-1. Administration of Sel was associated with increased HO-1 expression. Oxidative (malondialdehyde, reduced glutathione, superoxide dismutase, myeloperoxidase, and glutathione peroxidase activity) and nitrosative stress (nitric oxide) markers and markers of inflammation (interleukin 1β (IL-1β), IL-6, and IL-10) showed changes corresponding to HO-1 levels in rat groups. Tac group showed the highest expression of caspase-3. Sel exerted a protective role against Tac-induced lung toxicity.

Selenium attenuates venlafaxine hydrochloride-induced testicular damage in mice via modulating oxidative stress and apoptosis

The present study assessed the effect of selenium (Se) supplementation on Venlafaxine hydrochloride (VH)-induced testicular toxicity. Mice were segregated into Group I (C), Group II (0.5 ppm Se), Group III (VH at a dose 60 mg/kg b.w.) and Group IV (Se was given as per Group II, and VH was given as per Group III). After 10 weeks, sperm parameters, histology, sperm cell counts, antioxidants activities, apoptotic proteins and molecular analysis of testicular tissue were evaluated. Group III had significantly lower sperm concentration (from 2.17 ± 0.28 to 1.04 ± 0.22) and sperm motility (from 68.04 ± 5.5 to 21.47 ± 5.21), and showed an extensive vacuolisation in the germinal epithelium, abnormal basement membrane, and reduced germ cell number as compared to Group I. However, selenium supplementation in Group IV substantially increased sperm concentration (1.47 ± 0.48) and motility (33.27 ± 8.66), improved the histoarchitecture and repopulated the germ cells as observed by raised numbers of spermatogonia, spermatocytes, round spermatids and elongated spermatids contrasted to Group III. Group IV also showed a noteworthy decreased ROS, LPO levels, as well as expressions of Bax, caspase-9, and caspase-3 and increased the SOD, CAT, GPx, and GSH activities as well the expression of Bcl-2 as compared to Group III. This effect was further supported by FTIR analysis for nucleic acids. Thus, selenium supplementation showed significant protection against VH-induced testicular toxicity.

Selenium attenuates bisphenol A incurred damage and apoptosis in mice testes by regulating mitogen-activated protein kinase signalling

Being a vital micronutrient, along with a trace element, selenium (Se) protects the cells from oxidative stress (OS) in the form of selenoproteins. Bisphenol A (BPA) is a xeno-oestrogenic compound that adversely affects the spermatogenesis process by inducing oxidative stress, which ultimately leads to male infertility. Therefore, it is hypothesised that Se could protect against BPA-induced OS, and further germ cell death by modifying mitogen-activated protein kinase (MAPK) signalling. Male Balb/c mice were divided into four groups: Group I (C) (0.2 ppm Se), Group II (Se) (0.5 ppm Se), Group III (BPA) (0.2 ppm Se, and BPA = 1 mg/kg orally) and Group IV (Se + BPA) (0.5 ppm Se, and BPA = 1 mg/kg bodyweight orally). Results indicated that BPA-treated animals demonstrated a marked decrease in antioxidant enzyme activities (superoxide dismutase, catalase, redox ratio), a marked elevation in the expressions of stress-activated kinases (c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38) and the expressions of pro-apoptotic markers (caspase-9, caspase-8 and caspase-3). However, Se supplementation considerably restored the antioxidant enzyme activities and lowered the expressions of stress-activated kinases, which further down-regulated the apoptosis. Thus, Se supplementation demonstrated to be effective against BPA provoked testicular damage.

Silymarin alleviates docetaxel-induced central and peripheral neurotoxicity by reducing oxidative stress, inflammation and apoptosis in rats

Docetaxel (DTX) is a chemotherapeutic agent used in the treatment of various malignancies but is often associated with central and peripheral neurotoxicity. The aim of this study was to investigate the neuroprotective effect of silymarin (SLM) against DTX-induced central and peripheral neurotoxicities in rats. Rats received 25 and 50 mg/kg body weight SLM orally for seven consecutive days after receiving a single injection of 30 mg/kg body weight DTX on the first day. SLM significantly decreased brain lipid peroxidation level and ameliorated brain glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities in DTX-administered rats. SLM attenuated levels of nuclear factor kappa B (NF-κB), tumor necrosis factor-α (TNF-α), glial fibrillary acidic protein (GFAP) and activity of p38α mitogen-activated protein kinase (p38α MAPK) whereas caused an increase in levels of neural cell adhesion molecule (NCAM) in the brain and sciatic nerve of DTX-induced rats. In addition, SLM improved the histological structure of the brain and sciatic nerve tissues and decreased the expression of c-Jun N-terminal kinase (JNK) in the sciatic nerve whereas increased cyclic AMP response element binding protein (CREB) expression in the brain induced by DTX. Additionally, SLM markedly up-regulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and B-cell lymphoma-2 (Bcl-2) and downregulated the expression of Bcl-2 associated X protein (Bax) in the brain and sciatic nerve tissues of DTX-induced rats. Our results show that SLM can protect DTX-induced brain and sciatic nerve injuries by enhancing the antioxidant defense system and suppressing apoptosis and inflammation.

Selenium Diminishes Docetaxel-Induced Cell Death, Oxidative Stress, and Inflammation in the Laryngotracheal Epithelium of the Mouse

Docetaxel (DOCX) kills tumor cells through the formation of microtubules, calcium ion influx, apoptosis, and inflammation. However, DOCX has adverse effect on normal tissues through the production of reactive oxygen species (ROS), despite the adverse effect was inhibited by antioxidants. We investigated the protective role of selenium against DOCX-induced apoptosis and mitochondrial oxidative injury in laryngotracheal epithelial (LARYN) cells of mice. Thirty-two mice were divided into four groups (n = 8). The first group was used as a control. The second and third groups were treated with sodium selenite (Na-Sel) and DOCX, respectively. The fourth group was the combined group of Na-Sel and DOCX. At the end of the experiment, LARYN mucosa and cells were obtained from the mice. In the LARYN cells, the cell viability level was low in DOCX group, although glutathione peroxidase activity and cell viability level were increased by the treatment of Na-Sel. Increased lipid peroxidation, intracellular ROS, mitochondrial membrane depolarization, cell death levels, TNF-α, IL-1β, IL-6, caspase -3, and -9 activities in the DOCX group of LARYN cells were diminished by the treatment of Na-Sel. In conclusion, DOCX increased mitochondrial ROS, cell death, and inflammation in the LARYN cells, although the increase was reduced in the cells by Na-Sel treatment. DOCX-induced adverse oxidant, inflammatory, and apoptotic effects in the tissue might be reduced by the Na-Sel treatment.

Curcumin enhances cisplatin-induced human laryngeal squamous cancer cell death through activation of TRPM2 channel and mitochondrial oxidative stress

In this study, laryngeal tumor cells were killed through the production of excessive reactive oxygen species (ROS) and Ca²⁺ influx by cisplatin (CISP). Nevertheless, a resistance was determined against CISP treatment in the tumor cells. We have investigated the stimulating role of curcumin (CURC) on CISP-induced human laryngeal squamous cancer (Hep2) cell death through TRPM2 channel activation, and its protective role against the adverse effects of CISP in normal kidney (MPK) cells. Hep2 and MPK cells were divided into four groups as control group, CURC group (10μM for 24 hrs), CISP group (25 μM for 24 hrs), and CURC + CISP combination group. CISP-induced decrease of cell viability, cell count, glutathione peroxidase and glutathione level in Hep2 cells were further increased by CURC treatment, but the CISP-induced normal MPK cell death was reduced by the treatment. CISP-induced increase of apoptosis, Ca²⁺ fluorescence intensity, TRPM2 expression and current densities through the increase of lipid peroxidation, intracellular and mitochondrial oxidative stress were stimulated by CURC treatment. In conclusion, CISP-induced increases in mitochondrial ROS and cell death levels in Hep2 cells were further enhanced through the increase of TRPM2 activation with the effect of CURC treatment. CISP-induced drug resistance in Hep2 cells might be reduced by CURC treatment.

Mitochondrial oxidative stress-induced brain and hippocampus apoptosis decrease through modulation of caspase activity, Ca2+ influx and inflammatory cytokine molecular pathways in the docetaxel-treated mice by melatonin and selenium treatments

Docetaxel (DOCE) is widely used to treat several types of glioblastoma. Adverse effects DOCE seriously limit its clinical use in several tissues. Its side effects on brain cortex and hippocampus have not been clarified yet. Limited data indicated a protective effect of melatonin (MLT) and selenium (SELEN) on DOCE-induced apoptosis, Ca²⁺ influx and mitochondrial reactive oxygen species (ROS) in several tissues except brain and hippocampus. The purpose of this study is to discover the protective effect of MLT and SELEN on DOCE-induced brain and hippocampus oxidative toxicity in mice. MLT and SELEN pretreatments significantly ameliorated acute DOCE-induced mitochondrial ROS production in the hippocampus and brain tissues by reducing levels of lipid peroxidation, intracellular ROS production and mitochondrial membrane depolarization, while increasing levels of total antioxidant status, glutathione, glutathione peroxidase, MLT, α-tocopherol, γ-tocopherol, vitamin A, vitamin C and β-carotene in the tissues. Furthermore, MLT and SELEN pretreatments increased cell viability and TRPM2 channel activation in the hippocampus and brain followed by decreased activations of TNF-α, IL-1β, IL-6, and caspase -3 and - 9, suggesting a suppression of calcium ion influx, apoptosis and inflammation responses. However, modulator role of SELEN on the values in the tissues is more significant than in the MLT treatment. MLT and SELEN prevent DOCE-induced hippocampus and brain injury by inhibiting mitochondrial ROS and cellular apoptosis through regulating caspase -3 and - 9 activation signaling pathways. MLT and SELEN may serve as potential therapeutic targets against DOCE-induced toxicity in the hippocampus and brain.

Treatment with melatonin and selenium attenuates docetaxel-induced apoptosis and oxidative injury in kidney and testes of mice

Docetaxel (DTX) has been used in cancer treatments for several decades, but it results in many adverse apoptotic effects through excessive production of reactive oxygen species (ROS) in some tissue including the kidney and testes. We aimed to investigate potential modulatory roles of melatonin (MEL) and selenium (Se) against DTX-induced apoptosis and oxidative injury in the testes and kidney of mice. Thirty-two mice were divided into four equal groups as control, DTX, DTX + MEL and DTX + Se. DTX group was treated with a single intraperitoneal dose of DTX. After DTX treatment, MEL and Se were administered to the mice in the DTX + MEL and DTX + Se groups for 7 days respectively. Increased lipid peroxidation, ROS, apoptosis, caspase-3 and caspase-9 activities in the kidney and testes of the DTX group were diminished by treatment with MEL and Se. DTX-induced decreases in vitamin E (α- and γ-tocopherol), glutathione peroxidase and reduced glutathione levels in the kidney and testis were increased following MEL and Se treatments. In conclusion, our data show that MEL and Se can act as modulators against DTX-induced apoptosis and oxidative damage in the kidney and testis through up-regulation of glutathione and vitamin E and down-regulation of caspase pathways.