Neuro-protective effect of monomethyl fumarate on ischemia reperfusion injury in rats: Role of Nrf2/HO1 pathway in peri-infarct region
Post stroke recanalization has been associated with increased risk of oxidative stress. Stimulating endogenous antioxidant pathway by activation of nuclear factor erythroid-2-related factor-2 (Nrf2) plays a key role in neuronal defense against inflammation and oxidative stress in penumbra. Here, we explored whether monomethyl fumarate (MMF) could produce neuro-protection after ischemia/reperfusion (I/R) injury via Nrf2/HO1 activation. In male SD rats, middle cerebral artery was occluded for 90 min and confirmed using Laser Doppler flowmeter. MMF (10, 20 and 40 mg/kg) was administered in two divided doses at 30 min post ischemia and 5-10 min after reperfusion. After 24 h, effect on neurobehavioral parameters, infarct damage by TTC staining and MRI, oxidative stress and inflammatory cytokines were assessed. Expression studies of nuclear Nrf2 and cytoplasmic HO1 were performed in peri-infarct cortex and striatum; followed by dual immunofluorescence study to check the specific cell type. I/R induced neurobehavioral deficits and infarct damage were significantly (p < 0.05) attenuated by MMF (20 and 40 mg/kg). MMF, 20 mg/kg, significantly normalized I/R induced altered redox status and increased levels of TNF-α, IL-1β in the ipsilateral cortex. MRI data showed significantly reduced infarct in cortex but not in striatum after MMF treatment. Expression of nuclear Nrf2 and cytoplasmic HO1 were significantly (p < 0.05) increased in peri-infarct cortex after treatment with MMF. Additionally, dual immunofluorescence showed increased Nrf2 expression in neurons and HO1 expression in neurons as well as astrocytes in peri-infarct cortex after MMF treatment. Our results show the neuro-protective potential of MMF probably by restricting the progression of damage from striatum to cortex through activation of Nrf2/HO1 pathway in peri-infarct cortex.
4-O-methylhonokiol ameliorates type 2 diabetes-induced nephropathy in mice likely by activation of AMPK-mediated fatty acid oxidation and Nrf2-mediated anti-oxidative stress
Diabetic nephropathy (DN) is one of the most serious long-term complications of type 2 diabetes (T2D). 4-O-methylhonokiol (MH) is one of the biologically active ingredients extracted from the Magnolia stem bark. In this study, we aim to elucidate whether treatment with MH can ameliorate or slow-down progression of DN in a T2D murine model and, if so, whether the protective response of MH correlates with AMPK-associated anti-oxidant and anti-inflammatory effects. To induce T2D, mice were fed normal diet (ND) or high fat diet (HFD) for 3 months to induce insulin resistance, followed by an intraperitoneal injection of STZ to induce hyperglycemia. Both T2D and control mice received gavage containing vehicle or MH once diabetes onset for 3 months. Once completing 3-month MH treatment, five mice from each group were sacrificed as 3 month time-point. The rest mice in each group were sacrificed 3 months later as 6 month time-point. In T2D mice, the typical DN symptoms were induced as expected, reflected by increased proteinuria, renal lipid accumulation and lipotoxic effects inducing oxidative stress, and inflammatory reactions, and final fibrosis. However, these typical DN changes were significantly prevented by MH treatment for 3 months and even at 3 months post-MH withdrawal. Mechanistically, MH renal-protection from DN may be related to lipid metabolic improvement and oxidative stress attenuation along with increases in AMPK/PGC-1α/CPT1B-mediated fatty acid oxidation and Nrf2/SOD2-mediated anti-oxidative stress. Results showed the preventive effect of MH on the renal oxidative stress and inflammation in DN.
Antioxidant and immunomodulatory activity induced by stevioside in liver damage: In vivo, in vitro and in silico assays
Stevioside is a diterpenoid obtained from the leaves of Stevia rebaudiana (Bertoni) that exhibits antioxidant, antifibrotic, antiglycemic and anticancer properties. Therefore, we aimed to study whether stevioside has beneficial effects in liver injury induced by long-term thioacetamide (TAA) administration and investigated the possible underlying molecular mechanism using in vivo, in vitro and in silico approaches.
Modulation of cerulein-induced pancreatic inflammation by hydroalcoholic extract of curry leaf (Murraya koenigii)
This study was performed to study the in vitro and in vivo efficacy of hydroalcoholic extract of curry leaf (CLE) rich in carbazole alkaloids, against LPS-induced inflammation in Raw 264.7 macrophages and cerulein-induced acute pancreatitis, respectively. CLE was characterized by Fourier-transform infrared (FTIR) and liquid chromatography-mass spectrometry. Raw 264.7 cells were stimulated with LPS (2 μg/ml) and treated with CLE. The animals were treated with two doses of CLE (100 and 300 mg/kg). Plasma biochemistry, tissue lipid peroxidation, cytokines, and histological examination were evaluated. CLE was found to decently scavenge the activity of DPPH radical. It dose dependently suppressed nitrite production and oxidative stress in macrophages. CLE alleviated LPS-induced inflammation in macrophages as evident from the results of various inflammatory cytokines (IL-1β, IL-6, and TNF-α). In vivo, CLE reduced cerulein-induced pancreatic edema. CLE significantly abrogated the cerulein-induced lipid peroxidation, nitrite, MPO, and GSH levels. The inflammatory cytokines and p65-NFκB activity were significantly reduced by CLE. Mechanistically, CLE reduced the expression of NT, MPO, IL-1β, ICAM-1, and COX-2, and increased the expression of Nrf2. It reduced distant organ damage markers as well. We report for the first time that CLE holds substantial potential for the prevention of acute pancreatitis.
Activation of Nrf2 signaling by Icariin protects against 6-OHDA-induced neurotoxicity
Nerve damage is the main pathogenesis of neurodegenerative diseases. Recently, in search for a promising therapeutic target that could stop Neurodegenerative diseases progression, the anti-oxidant signaling pathway regulated by transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) has attracted new hopes. Icariin (ICA) exhibited a battery of pharmacological properties, including anti-oxidation, anti-aging, anti-inflammation activities. Recent studies indicate ICA conferred neuroprotection against brain ischemic injury and neurodegenerative diseases. However, the mechanisms underlying ICA-mediated neuroprotection remain unelucidated. This study aimed at analyzing whether ICA evoked neuroprotection against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in PC12 cells and the mechanisms of action. ICA protected against 6-OHDA-induced neuronal damage, accompanied by the inhibition of cell apoptosis through the marked decreases in the Bax/Bcl-2 ratio, cytochrome C release and caspase-3 cleavage. In addition, the activation of Nrf2 signaling pathway was responsible for ICA-mediated neuroprotection. First, ICA relieved reactive oxygen species (ROS) accumulation and increased superoxide dismutase (SOD) generation via the activation of Nrf2 signaling. Second, Nrf2 knockdown by siRNA reversed ICA-mediated neuroprotection. These experiments offer a promising avenue to validate Nrf2 for a compelling target with ICA as a therapeutic strategy to enhance endogenous brain defense mechanisms against Neurodegenerative diseases. (Delete this sentence and change to "Together, these results suggested ICA-mediated neuroprotection might be attributable to the activation of Nrf2 pathway via anti-oxidative signaling pathways.") This article is protected by copyright. All rights reserved.
Differential induction of nuclear factor-like 2 signature genes with toll-like receptor stimulation
Inflammation is associated with production of reactive oxygen species (ROS) and results in the induction of thioredoxin (TXN) and peroxiredoxins (PRDXs) and activation of nuclear factor-like 2 (Nrf2). In this study we have used the mouse RAW 264.7 macrophage and the human THP-1 monocyte cell line to investigate the pattern of expression of three Nrf2 target genes, PRDX1, TXN reductase (TXNRD1) and heme oxygenase (HMOX1), by activation of different Toll-like receptors (TLRs). We found that, while the TLR4 agonist lipopolysaccharide (LPS) induces all three genes, the pattern of induction with agonists for TLR1/2, TLR3, TLR2/6 and TLR7/8 differs depending on the gene and the cell line. In all cases, the extent of induction was HMOX1>TXNRD1>PRDX1. Since LPS was a good inducer of all genes in both cell lines, we studied the mechanisms mediating LPS induction of the three genes using mouse RAW 264.7 cells. To assess the role of ROS we used the antioxidant N-acetylcysteine (NAC). Only LPS induction of HMOX1 was inhibited by NAC while that of TXNRD1 and PRDX1 was unaffected. These three genes were also induced by phorbol myristate acetate (PMA), a ROS-inducer acting by activation of protein kinase C (PKC). The protein kinase inhibitor staurosporine inhibited the induction of all three genes by PMA but only that of HMOX1 by LPS. This indicates that activation of these genes by inflammatory agents is regulated by different mechanisms involving either ROS or protein kinases, or both.
Embelin attenuates cisplatin-induced nephrotoxicity: Involving inhibition of oxidative stress and inflammation in addition with activation of Nrf-2/Ho-1 pathway
In kidneys, elevated levels of inflammatory cytokines and oxidative stress were observed in nephrotoxicity triggered by cisplatin. Embelin has the anti-inflammatory property. It also got anti-tumorigenic and antioxidant properties. In this research, we analyzed the actions of embelin on nephrotoxicity triggered by cisplatin and vital actions by which it increases antioxidant actions and corrects the inflammation after embelin administration during nephrotoxicity triggered by cisplatin. Kidney function markers including blood urea nitrogen; serum creatinine; the markers of oxidative stress like malondialdehyde (MDA), antioxidant systems like glutathione, superoxide dismutase, glutathione S-transferase, catalase, and glutathione reductase; inflammation markers like nuclear factor-κB (NF-κB), tumor necrosis factor-α (TNF-α), and interleukin-1 beta (IL-1β); and the extent of nuclear factor-erythroid-2 p45-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1) were determined. Histopathology studies of kidneys were also used to analyze nephrotoxicity induced by cisplatin. Treatment with embelin (25 and 50 mg/kg) upgrades the function of kidneys, by elevating antioxidant levels and reducing the MDA level in cisplatin-administered rats. Embelin treatment demonstrated a significant curtailment of oxidative stress as well as increased the activities of antioxidant enzymes, endogenously. Cisplatin upregulates cytokines (i.e., TNF-α and IL-1β) and NF-κB, and downregulates Nrf2 and HO-1. Embelin treatment also reduced the infiltration of neutrophils in the renal tubules and thus reduced the level of histological impairment. The outcome of this study implements that the signaling pathway of Nrf2/HO-1 may be the principal mechanism of embelin for protection from nephrotoxicity triggered by cisplatin, and thus, embelin diminishes oxidative stress and inflammation by impeding NF-κB. © 2019 BioFactors, 2019.
CXA-10, a Nitrated Fatty Acid, is Renoprotective in Deoxycorticosterone Acetate-Salt Nephropathy
Underlying pathogenic mechanisms in chronic kidney disease (CKD) include chronic inflammation, oxidant stress, and matrix remodeling associated with dysregulated NF-ĸB, NRF2 and SMAD signaling pathways, respectively. Important cytoprotective mechanisms activated by oxidative inflammatory conditions are mediated by nitrated fatty acids (NO2-FA) that covalently modify proteins to limit inflammation and oxidant stress. In the present study we evaluated the effects of chronic treatment with CXA-10 (10-nitro-9(E)-octadec-9-enoic acid) in the uni-nephrectomized deoxycorticosterone acetate (DOCA)-high salt mouse model of CKD. After 4 weeks of treatment, CXA-10 (2.5 mpk, p.o.) significantly attenuated increases in plasma cholesterol, heart weight and kidney weight observed in the model without impacting systemic arterial blood pressure. CXA-10 also reduced albuminuria, nephrinuria, glomerular hypertrophy and glomerulosclerosis in the model. Inflammatory (MCP-1) and fibrosis (collagen, fibronectin, PAI-1 and osteopontin) renal biomarkers were significantly reduced in the CXA-10 (2.5 mpk) group. The anti-inflammatory and anti-fibrotic effects, as well as glomerular protection were not observed in the enalapril treated group. Also, CXA-10 appears to exhibit hormesis as all protective effects observed in the low dose group were absent in the high dose group (12.5 mpk). Taken together, these findings demonstrate that at the appropriate dose, the nitrated fatty acid CXA-10 exhibits anti-inflammatory and anti-fibrotic effects in the kidney and limits renal injury in a model of CKD.
Astragaloside IV Protects Against Oxidized Low-Density Lipoprotein (ox-LDL)-Induced Endothelial Cell Injury by Reducing Oxidative Stress and Inflammation
BACKGROUND Endothelial injury is the main mechanism of atherosclerosis, and is caused by oxidized low-density lipoprotein (ox-LDL). Astragaloside IV (AS-IV) is the primary active ingredient of the Chinese herb Huangqi, and exhibits antioxidant and anti-inflammatory properties in cardiovascular diseases. This study investigated the protective effect of AS-IV in human umbilical vein endothelial cells (HUVECs). MATERIAL AND METHODS HUVEC cells were induced with ox-LDL to establish an in vitro atherosclerosis model. Then HUVECs were pretreated for 1 h with AS-IV at different concentrations (10, 20, and 50 μM) and then exposed to ox-LDL (100 μg/mL) for 48 h. The cell viability, lactate dehydrogenase (LDH) release, apoptosis, migration, intracellular reactive oxygen species (ROS), and NADPH oxidase activity of HUVECs were measured. qRT-PCR was performed to measure the mRNA expressions of Nrf2, HO-1, TNFalpha, and IL-6. Enzyme-linked immunosorbent assay (ELISA) was performed to measure the supernatant contents of TNFalpha and IL-6. RESULTS Exposure of HUVECs to ox-LDL reduced cell viability and migration, induced apoptosis, and increased intracellular ROS production and NADPH oxidase. Pretreatment with AS-IV (10, 20, and 50 μM) significantly enhanced the cell viability and migration, suppressed LDH release, apoptosis, ROS production, and NADPH oxidase in HUVECs, in a concentration-dependent manner. The AS-IV (50 μM) alone did not show significant differences from control. AS-IV increased mRNA expressions of Nrf2 and HO-1 and decreased mRNA expressions of TNFalpha and IL-6 in the ox-LDL-HUEVC cells. Furthermore, AS-IV reduced supernatant contents of TNFalpha and IL-6. CONCLUSIONS Astragaloside IV prevents ox-LDL-induced endothelial cell injury by reducing apoptosis, oxidative stress, and inflammatory response.
Olive oil promotes wound healing of mice pressure injuries through NOS-2 and Nrf2
The pressure injury environment is characterized by overproduction of reactive oxygen species and exacerbated inflammation, which impair the healing of these lesions. Mediterranean-like diet may be a good intervention to improve the healing of pressure injury due to its anti-inflammatory and antioxidant components. So, this study evaluated the hypothesis that olive oil, as a main source of lipid in Mediterranean diet, could improve cutaneous wound healing of pressure injury in mice. Male Swiss mice were randomly divided into standard, olive oil or soybean oil plus olive oil groups and fat represented 10% of total calories in all groups. Four weeks after the beginning of diet administration, two cycles of ischemia-reperfusion (IR) by external application of two magnets disks were performed in the dorsal skin to induce pressure injury formation. Fourteen days after the end of the second IR cycle, olive oil based diet reduced neutrophils cells and cyclooxygenase-2 protein expression, increased nitric oxide synthase-2 and protein and lipid oxidation. Olive oil based diet also increased nuclear factor erythroid 2-related factor 2 protein expression and collagen type I precursor protein expression. In addition, olive oil based diet administration promoted wound closure 7, 10 and 14 days after the end of the second IR cycle. These findings support the hypothesis that olive oil based diet improves cutaneous wound healing of pressure injury in mice through the reduction of inflammation and stimulation of redox equilibrium.
The protective effect of oleanolic acid on NMDA-induced MLE-12 cells apoptosis and lung injury in mice by activating SIRT1 and reducing NF-κB acetylation
Overactivation of the N-methyl-d-aspartate (NMDA) receptor promotes oxidative stress, aggravates the inflammatory response and induces excitotoxic lung injury. NMDA is a synthetic agonist that selectively activates the NMDA receptor. Oleanolic acid (OA) is a natural anti-inflammatory and antioxidant compound. This study investigated the effect and possible mechanism of OA on NMDA-induced acute lung injury (ALI) in mice. OA pretreatment alleviated NMDA-induced histological lung changes and ameliorated pulmonary oedema and pulmonary permeability. At the same time, OA inhibited inflammatory cell infiltration and decreased the levels of tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β in the lung and bronchoalveolar lavage fluid (BALF). OA markedly decreased malondialdehyde (MDA) production and increased the superoxide dismutase (SOD) and glutathione (GSH) contents of the lung in vivo. Meanwhile, we first found that NMDA increased LDH activity and decreased cell viability, and induced oxidative stress and apoptosis in mouse lung epithelial (MLE)-12 cells. By employing SRT1720 and sirtinol, the activator and inhibitor of sirtuin 1 (SIRT1), we found that SRT1720 partially eliminated the increase in ROS，and sirtinol further promoted the increase in ROS caused by NMDA. OA increased MLE-12 cells viability and attenuated oxidative stress after NMDA challenge in vitro. OA suppressed NMDA-induced MLE-12 cells apoptosis, while sirtinol inhibited the effect of OA. In addition, OA significantly upregulated the levels of SIRT1, nuclear-related factor 2(Nrf2) and Bcl-2 protein and downregulated the levels of acetylated nuclear factor-kappa B (NF-κB), NLRP3 and Bax protein. In conclusion, OA attenuated NMDA-induced excitotoxic lung injury, potentially through its anti-inflammatory, antioxidative stress and anti-apoptotic effects. The mechanism may be related to activating SIRT1 and reducing NF-κB acetylation.
Z-Ligustilide protects vascular endothelial cells from oxidative stress and rescues high fat diet-induced atherosclerosis by activating multiple NRF2 downstream genes
Oxidative stress-induced endothelial dysfunction is considered to exert a vital role in the development of atherosclerotic coronary heart disease (CHD). NRF2 is a key transcriptional factor against oxidative stress through activation of multiple ARE-mediated genes. Z-Lig is derived from the Ligusticum species with antitumor, anti-inflammation and neuroprotection activities. However, the antioxidant potentials of Z-Lig on endothelial dysfunction and atherosclerosis have not been well elucidated. Therefore, in the present work, we appraise the cytoprotective property and anti-atherosclerosis effect of Z-Lig.
Early life environment influences the trajectory of post-partum weight loss in adult female rats
The physiological processes of pregnancy and lactation require profound changes in maternal metabolism and energy balance. The timescale of metabolic reversion after pregnancy, in particular post-partum weight loss, is highly variable between individuals. Currently, mechanisms influencing post-partum metabolic recovery are not well understood. The hypothesis tested here is that, in common with other metabolic and obesity-related outcomes, capacity for post-partum weight loss is influenced by developmental programming.
Signal Transduction, Ageing and Disease
Ageing is defined by the loss of functional reserve over time, leading to a decreased tissue homeostasis and increased age-related pathology. The accumulation of damage including DNA damage contributes to driving cell signaling pathways that, in turn, can drive different cell fates, including senescence and apoptosis, as well as mitochondrial dysfunction and inflammation. In addition, the accumulation of cell autonomous damage with time also drives ageing through non-cell autonomous pathways by modulation of signaling pathways. Interestingly, genetic and pharmacologic analysis of factors able to modulate lifespan and healthspan in model organisms and even humans have identified several key signaling pathways including IGF-1, NF-κB, FOXO3, mTOR, Nrf-2 and sirtuins. This review will discuss the roles of several of these key signaling pathways, in particular NF-κB and Nrf2, in modulating ageing and age-related diseases.
Melatonin Inhibits Lipopolysaccharide-Induced Inflammation and Oxidative Stress in Cultured Mouse Mammary Tissue
To determine whether melatonin can protect cultured mouse mammary tissue from lipopolysaccharide- (LPS-) induced damage, we investigated the effects of melatonin on the mRNA and protein levels of proinflammatory cytokines and chemokines in LPS-stimulated mammary tissue . This study also examined the IgG level in both cultured mammary tissue and the culture medium. In addition, we investigated the potential benefits of melatonin on the expression of antioxidant relative genes following LPS treatment in cultured mammary tissue and evaluated ROS level in the culture medium. The results demonstrate that melatonin inhibited the mRNA expression of , , , , , and and the production of these cytokines and chemokines and IgG in LPS-stimulated mouse mammary tissue . In addition, melatonin increased but decreased and mRNA expression after LPS stimulation. Similarly, the decreased level of dityrosine in the culture medium was increased by treatment with melatonin, while increased nitrite level was suppressed. This study confirms that melatonin inhibited LPS-induced inflammation and oxidative stress in cultured mouse mammary tissue. It might contribute to mastitis therapy while treating antibiotic resistance.