Heme Oxygenase-1 Expression Research Articles

Pericyte Control of Gene Expression in the Blood-Brain Barrier Endothelium: Implications for Alzheimer's Disease.

A strong body of evidence suggests that cerebrovascular pathologies augment the onset and progression of Alzheimer's disease (AD). One distinctive aspect of this cerebrovascular dysfunction is the degeneration of brain pericytes-often overlooked supporting cells of blood-brain barrier endothelium. The current study investigates the influence of pericytes on gene and protein expressions in the blood-brain barrier endothelium, which is expected to facilitate the identification of pathophysiological pathways that are triggered by pericyte loss and lead to blood-brain barrier dysfunction in AD. Bioinformatics analysis was conducted on the RNA-Seq expression counts matrix (GSE144474), which compared solo-cultured human blood-brain barrier endothelial cells against endothelial cells co-cultured with human brain pericytes in a non-contact model. We constructed a similar cell culture model to verify protein expression using western blots. The insulin resistance and ferroptosis pathways were found to be enriched. Western blots of the insulin receptor and heme oxygenase expressions were consistent with those observed in RNA-Seq data. Additionally, we observed more than 5-fold upregulation of several genes associated with neuroprotection, including insulin-like growth factor 2 and brain-derived neurotrophic factor. Results suggest that pericyte influence on blood-brain barrier endothelial gene expression confers protection from insulin resistance, iron accumulation, oxidative stress, and amyloid deposition. Since these are conditions associated with AD pathophysiology, they imply mechanisms by which pericyte degeneration could contribute to disease progression.

Anti-aging mechanism and effect of treatment with raw and wine-steamed Polygonatum sibiricum on D-galactose-induced aging in mice by inhibiting oxidative stress and modulating gut microbiota.

Polygonatum sibiricum (PS) is a traditional Chinese medicine (TCM) first recorded in Mingyi Bielu. The book documents that PS can nourish five internal organs, be taken for a long time, relax the body and prolong lifespan. Presently, PS is widely used in TCM to prevent premature graying of hair. Based on TCM theory and clinical trials, the wine steaming processed product from PS provides a better effect. However, no published study has elucidated the anti-aging mechanism. The study aim was to investigate the anti-aging mechanism of PS and its wine steaming processed product in mice, specifically focusing on the effect of D-galactose (D-gal) surrounding the intestinal flora and the Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor 2-antioxidant response elements (Keap1/Nrf2/ARE) pathway. The chemical components in Raw PS (RPS) and Wine-steamed PS (WPS) were identified by ultra-performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap HRMS). An aging model using Kunming mice was established through intraperitoneally injected D-gal. Concentrations of RPS and WPS at 5, 10, or 15g/kg/day levels were administered intragastrically, respectively. The body weight, liver and spleen indexes, superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and malondialdehyde (MDA) activities in serum and brain tissue were recorded. Hematoxylin and eosin (HE) stained brain tissue was histopathologically examined. The expressions of Keap1, Nrf2 and heme oxygenase 1 (HO-1) in the brain tissue at the mRNA and protein levels were respectively detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blot (WB). Moreover, an Illumina Hiseq platform was used for 16S ribosomal RNA (16S rRNA) high-throughput sequencing to evaluate the proportions of intestinal flora in aging mice. The proportions of saccharides, flavonoids, and triterpene acids were different between RPS and WPS. In the aging model mice, WPS outperformed RPS in improving body weight and mental state by increasing the spleen index, SOD and GSH-PX activities, decreasing the liver index and MDA activities, and restoring the histopathological morphology in D-gal-induced aging mice. At the mRNA levels, RPS and WPS significantly reduced the expression of Keap1 and increased the expressions of Nrf2 and HO-1. The trend in protein expressions was similar to that of the mRNA results, and WPS had a stronger effect than RPS. Fecal microbiota analysis showed that RPS and WPS restored intestinal microbiota proportions to normal levels. The results demonstrated that PS and its WPS had a positive effect in relieving oxidative stress in aging mice. WPS outperformed RPS, which might be related to the activation of the Keap1/Nrf2/ARE pathway and regulation of intestinal flora.

Effects of Dietary Callicarpa nudiflora Aqueous Extract Supplementation on Growth Performance, Growth Hormone, Antioxidant and Immune Function, and Intestinal Health of Broilers.

C. nudiflora is notably rich in flavonoids and phenylethanoid glycosides, making it a significant natural source of antioxidants. We examined the effects of C. nudiflora aqueous extract (CNE) on growth performance, antioxidant function, immunity, intestinal barrier function, nutrient transporters, and microbiota of broilers. A total of 360 one-day-old broilers were randomly assigned to four treatment groups: a basal diet with 0 (control, CON), 300 mg/kg (CNEL), 500 mg/kg (CNEM), and 700 mg/kg (CNEH) CNE for 42 days. CNEL and CNEM groups quadratically increased body weight and average daily gain but decreased feed-to-gain ratios during the starter and whole phases. Regarding the immune response of broilers, CNE treatment linearly down-regulated jejunal myeloid differentiation factor 88 (MyD88) expression and interleukin-1β (IL-1β) and interferon-γ expression in the liver (d 21), while decreasing jejunal IL-1β expression and the concentration of serum tumor necrosis factor-α and interleukin-6 (d 42). The CNEM and CNEH groups had lower MyD88 and nuclear factor kappa B expression in the liver (d 21) compared to the CON group. Broilers in the CNEL and CNEM groups had higher spleen index and thymus index (d 21) and interleukin-10 expression from the liver and jejunal mucosa (d 42) than that in the CON group. For the antioxidant capacity of broilers, CNE treatment linearly decreased the content of malonaldehyde and increased the activity of total antioxidant capacity in serum (d 42). CNEM and CNEH groups linearly increased the activity of superoxide dismutase in serum and heme oxygenase-1 expression in the liver, while increasing the activity of glutathione peroxidase in serum, jejunal nuclear factor E2-related factor 2 expression, and NAD(P)H quinone oxidoreductase 1 expression in the liver (d 42). As for the growth hormone of broilers, CNEM group increased the level of serum insulin-like growth factor 1 and up-regulated jejunal glucagon-like peptide 2 (GLP-2) expression (d 21). Broilers in the CNEM and CNEH groups had higher jejunal GLP-2 expression and growth hormone (GH) expression in the liver and the level of serum GH (d 42) than that in the CON group. Additionally, the villus height and jejunal Occludin and Claudin-1 expression in the CNEM group increased. CNE-containing diets resulted in a linear increase in the expression of jejunal zonula occluden-1 (d 21), villus height to crypt depth ratio, jejunal Occludin, excitatory amino acid transporters-3, and peptide-transporter 1 (d 42). The regulation of Oscillospira, Ruminococcaceae_Ruminococcus, and Butyricicoccus genera indicated that CNEH altered the composition of the cecal microbiota. In general, supplementing broilers with C. nudiflora aqueous extract could boost hormones, immune and antioxidant function, and gut health, improving their growth performance. Hence, CNE was a promising poultry feed additive, with 500 mg/kg appearing to be the optimal dose.

Beneficial Effects of Oral Carbon Monoxide on Doxorubicin-Induced Cardiotoxicity.

Doxorubicin and other anthracyclines are crucial cancer treatment drugs. However, they are associated with significant cardiotoxicity, severely affecting patient care and limiting dosage and usage. Previous studies have shown that low carbon monoxide (CO) concentrations protect against doxorubicin toxicity. However, traditional methods of CO delivery pose complex challenges for daily administration, such as dosing and toxicity. To address these challenges, we developed a novel oral liquid drug product containing CO (HBI-002) that can be easily self-administered by patients with cancer undergoing doxorubicin treatment, resulting in CO being delivered through the upper gastrointestinal tract. HBI-002 was tested in a murine model of doxorubicin cardiotoxicity in the presence and absence of lung or breast cancer. The mice received HBI-002 twice daily before doxorubicin administration and experienced increased carboxyhemoglobin levels from a baseline of ≈1% to 7%. Heart tissue from mice treated with HBI-002 had a 6.3-fold increase in CO concentrations and higher expression of the cytoprotective enzyme heme oxygenase-1 compared with placebo control. In both acute and chronic doxorubicin toxicity scenarios, HBI-002 protected the heart from cardiotoxic effects, including limiting tissue damage and cardiac dysfunction and improving survival. In addition, HBI-002 did not compromise the efficacy of doxorubicin in reducing tumor volume, but rather enhanced the sensitivity of breast 4T1 cancer cells to doxorubicin while simultaneously protecting cardiac function. These findings strongly support using HBI-002 as a cardioprotective agent that maintains the therapeutic benefits of doxorubicin cancer treatment while mitigating cardiac damage.

Mechanism of tetramethylpyrazine intervention with ischemia-reperfusion rats based on Nrf2/HO-1/CXCR4 pathway through regulating neural stem cell migration

This study aims to decipher the mechanism of tetramethylpyrazine(TMP) in regulating the migration of neural stem cells(NSCs) in the rat model of middle cerebral artery occlusion(MCAO) via the nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)/C-X-C motif chemokine receptor 4(CXCR4) pathway. SD rats were randomized into sham, MCAO(model), and tetramethylpyrazine(TMP, 20 mg·kg~(-1) and 40 mg·kg~(-1)) groups. The neurological impairment was assessed by the modified neurological severity score(mNSS). The immunofluorescence assay was employed to detect the cells stained with both 5-bromodeoxyuridine(BrdU) and doublecortin(DCX) in the brain tissue. The effect of TMP on the migration of C17.2 cells was observed. Western blot was employed to determine the protein levels of Nrf2, HO-1, p62, NAD(P)H quinone oxidoreductase 1(NQO1), stromal cell-derived factor 1(SDF-1), and CXCR4 in the brain tissue and C17.2 cells. The results showed that after 7 days and 21 days of mode-ling, the mNSS and BrdU~+/DCX~+ cells were increased, and the expression of Nrf2 and CXCR4 in the brain tissue was up-regulated. Compared with the model group, TMP(40 mg·kg~(-1)) reduced the mNSS, increased the number of BrdU~+/DCX~+ cells, and up-regulated the expression of Nrf2, CXCR4, and SDF-1. In addition, TMP promoted the migration of C17.2 cells and up-regulated the expression of p62, Nrf2, HO-1, and NQO1 in a time-and dose-dependent manner. The expression was the highest at the time point of 12 h in the TMP(50 μg·mL~(-1)) group(P<0.01). In conclusion, TMP activates the Nrf2/HO-1/CXCR4 pathway to promote the migration of NSCs to the ischemic area, thus exerting the therapeutic effect on the ischemia-reperfusion injury. This study provides experimental support for the application of TMP in ischemic stroke.

Emodin alleviates intestinal ischemia/reperfusion-induced lung injury by upregulating HO-1 expression via PI3K/AkT pathway

BackgroundEmodin, a natural anthraquinone derivative found in various Chinese medicinal herbs, has been proved to be an effective therapeutic agent in the treatment of many diseases. However, its effect on lung injury after intestinal ischemia/reperfusion injury remains unknown. This research was designed to investigate whether emodin protects against intestinal ischemia/reperfusion-induced lung injury and to elucidate the underlying molecular mechanisms in vivo and in vitro. MethodsIntestinal ischemia/reperfusion injury was induced by occluding the superior mesenteric artery in mice, and mouse lung epithelial-12 cells were subjected to oxygen-glucose deprivation and reoxygenation to establish an in vitro model. ResultsOur data indicated that emodin treatment reduced intestinal ischemia/reperfusion-induced oxidative stress, inflammation and apoptosis in lung tissues and alleviated lung injury. However, the protective effects of emodin on intestinal ischemia/reperfusion-induced lung injury were reversed by the protein kinase B inhibitor triciribine or the heme oxygenase-1 inhibitor tin protoporphyrin IX. The protein kinase inhibitor triciribine also downregulated the expression of heme oxygenase-1. ConclusionIn conclusion, our data suggest that emodin treatment protects against intestinal ischemia/reperfusion-induced lung injury by enhancing heme oxygenase-1 expression via activation of the PI3K/protein kinase pathway. Emodin may act as a potential therapeutic agent for the prevention and treatment of lung injury induced by intestinal ischemia/reperfusion.

Kidney-targeted antioxidant salvianolic acid B nanoparticles restoring lysosome homeostasis for acute kidney injury therapy

Acute kidney injury (AKI) is highly correlated with oxidative stress, and the application of antioxidants is one of the promising treatments. Salvianolic acid B (SAB) is a natural polyphenol with powerful antioxidant effects. Due to its inherent characteristic of inferior bioavailability, its clinical application is impeded. In this study, small SAB-incorporated nanoparticles (SFA) were synthesized via the self-assembly of SAB, ferric ions, and bovine serum albumin (BSA). Apart from antioxidant activity, the SFA nanoparticles were found to efficiently restore lysosome dysfunction induced by reactive oxygen species (ROS) in human kidney proximal tubular epithelial HK-2 cells. The small size and BSA incorporation make the SFA nanoparticles to be promising AKI-targeting nanoparticles. They are rapidly accumulated and long-term retained in injured kidneys of glycerol-induced AKI mice, especially in the proximal tubules which are the key lesion location during AKI. In vivo studies indicate that SFA nanoparticles show a superior protective effect compared with the free drug by suppressing oxidative stress and maintaining lysosome homeostasis indicated by enhanced heme oxygenase-1 (HO-1) expression and restored cathepsin B (CTSB) activity, respectively. In summary, this study develops a delivery system for the antioxidant SAB enhancing local delivery and offering an additional lysosome restoring mechanism for AKI therapy.

Solid state fermentation of Diaphragma juglandis fructus with Aspergillus niger alleviates hydrogen peroxide-induced oxidative stress in HepG2 cells via Nrf2 signaling pathway

Diaphragma juglandis fructus (DJF) is a traditional medicine, which is rich in bioactive polyphenols and has been proven to exhibit better antioxidant activity. However, the potential effects of fermentation of DJF on oxidative stress remains unclear. Herein, this study aimed to investigate the impact of solid-state fermentation (SSF) with Aspergillus niger (A. niger) on the polyphenol content and biological activity in DJF. Furthermore, compared with unfermented Diaphragma juglandis fructus (UF-DJF) extracts, ellagic acid (EA), sinapic acid (SA) and (+)-catechin (CA) displayed the highest increase in soluble phenolics (SPs) of fermented Diaphragma juglandis fructus (F-DJF) extracts. Thus, we explored the protective effect of EA, SA, CA and co-existing of EA, SA, CA against hydrogen peroxide (H2O2)-induced oxidative stress in HepG2 cells. Our results demonstrated that the insoluble-bound phenolics (IBPs) could be released, thereby increasing the SPs content and in vitro antioxidant activity after SSF. In addition, we also found that F-DJF extracts had the best inhibitory effect on three digestive enzymes among UF-DJF, before fermented Diaphragma juglandis fructus (BF-DJF) and F-DJF extracts. Moreover, our results revealed that pre-treatment with EA, SA, CA and co-present of EA, SA, CA could protect HepG2 cells from oxidative damage through activating the Nrf2 signaling pathway and up-regulating the expression of heme oxygenase-1 (HO-1), NAD(P)H dehydrogenase quinone1 (NQO1), glutamate-cysteine ligase catalytic subunit (GCLC), cytoplasmic Cu-Zn-SOD (SOD1), mitochondrial Mn-SOD (SOD2) and catalase (CAT). Remarkably, the co-presence of EA, SA, CA showed the best protective effect. In conclusion, our research highlights SSF is an effective method for enhancing polyphenol content and biological activity in DJF. Moreover, these findings provide novel insights into the role of F-DJF extracts in prevention chronic diseases associated with oxidative stress and the possibility of their application in functional foods. In addition, fermentation may be a reliable strategy to enhance the medicinal value of DJF.

The impact of sestrin2 on reactive oxygen species in diabetic retinopathy.

Diabetic retinopathy (DR) is a significant complication of diabetes that often leads to blindness, impacting Müller cells, the primary retinal macroglia involved in DR pathogenesis. Reactive oxygen species (ROS) play a crucial role in the development of DR. The objective of this study was to investigate the involvement of sestrin2 in DR using a high-glucose (HG)-induced Müller cell model and assessing cell proliferation with 5-ethynyl-2-deoxyuridine (EdU) labeling. Following this, sestrin2 was upregulated in Müller cells to investigate its effects on ROS, tube formation, and inflammation both in vitro and in vivo, as well as its interaction with the nuclear factor erythroid2-related factor 2 (Nrf2) signaling pathway. The findings demonstrated a gradual increase in the number of EdU-positive cells over time, with a subsequent decrease after 72 h of exposure to high glucose levels. Additionally, the expression of sestrin2 exhibited a progressive increase over time, followed by a decrease at 72 h. The rh-sestrin2 treatment suppressed the injury of Müller cells, decreased ROS level, and inhibited the tube formation. Rh-sestrin2 treatment enhanced the expression of sestrin2, Nrf2, heme oxygenase-1 (HO-1), and glutamine synthetase (GS); however, the ML385 treatment reversed the protective effect of rh-sestrin2. Finally, we evaluated the effect of sestrin2 in a DR rat model. Sestrin2 overexpression treatment improved the pathological injury of retina and attenuated the oxidative damage and inflammatory reaction. Our results highlighted the inhibitory effect of sestrin2 in the damage of retina, thus presenting a novel therapeutic sight for DR.

Protective effect of kaempferol glucoside against lipopolysaccharide-caused acute lung injury via targeting Nrf2/NF-κB/NLRP3/GSDMD: Integrating experimental and computational studies

The current study explored the protective potential of kaempferol 3-sophoroside-7-glucoside (KSG) against acute lung injury (ALI). Pre-treatment with KSG effectively secured mice from ALI and showed similar efficaciousness to dexamethasone. KSG markedly increased the survival rate and alleviated lung pathological lesions induced by lipopolysaccharide (LPS). Furthermore, KSG attenuated differential and total cell counts in BALF (bronchoalveolar lavage fluid) and MPO (myeloperoxidase) activity. KSG counteracted the NF-κB (nuclear factor-κB) activation and significantly ameliorated the downstream inflammatory cytokine, TNF-α (tumor necrosis factor-α). Simultaneously, KSG suppressed the over-expression of NLRP3 (NOD-like receptor protein 3), caspase-1, and pro-inflammatory cytokine interleukin IL-1β (interleukine-1β) and prohibited the elevation of the pyroptotic parameter GSDMD-N (N-terminal domain of gasdermin D) induced by LPS challenge. In addition, KSG significantly enhanced Nrf2 (nuclear-factor erythroid-2-related factor) and HO-1 (heme-oxygenase-1) expression. Meanwhile, KSG mitigated lipid peroxidative markers (malondialdehyde, protein carbonyl and 4-hydroxynonenal) and boosted endogenous antioxidants (superoxide dismutase/reduced glutathione/catalase) in lung tissue. In silico analyses revealed that KSG disrupts Keap1-Nrf2 protein–protein interactions by binding to the KEAP1 domain, consequently activating Nrf2. Specifically, molecular docking demonstrated superior binding affinity of KSG to KEAP1 compared to the reference inhibitor, with docking scores of −9.576 and −6.633 Kcal/mol, respectively. Additionally, the MM-GBSA binding free energy of KSG (−67.25 Kcal/mol) surpassed that of the reference inhibitor (−56.36 Kcal/mol). Furthermore, MD simulation analysis revealed that the KSG-KEAP1 complex exhibits substantial and stable binding interactions with various amino acids over a duration of 100 ns. These findings showed the protective anti-inflammatory and anti-oxidative modulatory efficiencies of KSG that effectively counteracted LPS-induced ALI and encouraged future research and clinical applications of KSG as a protective strategy for ALI.

Promotion of 14-3-3ζ/Heme Oxygenase-1 Axis on Endotoxin-Induced Uveitis and Microglia Ferroptosis in Mice

ABSTRACT Purpose Uveitis is a common, sight-threatening inflammatory ocular disease and is the main cause of blindness, which is caused by autoimmune response, infection, and injury. The contribution of 14-3-3ζ in uveitis remains obscure. This study aims to investigate the role of 14-3-3ζ in regulating ferroptosis in retinal inflammation and its contribution to uveitis. Methods A lipopolysaccharide (LPS)-induced uveitis mouse model and BV-2 cell line were used to examine the effect of LPS stimulation on the expression of 14-3-3ζ and ferroptosis in microglia. The expression of heme oxygenase-1 (HO-1) was also analyzed to understand its role in promoting microglial ferroptosis. Results We found that LPS stimulation increased the expression of 14-3-3ζ and promoted ferroptosis in microglia. Additionally, 14-3-3ζ was found to promote microglial ferroptosis by stabilizing the expression of HO-1. These findings suggest that the 14-3-3ζ/HO-1 axis plays a crucial role in promoting microglial ferroptosis in retinal inflammation. Conclusion The study provides valuable insights into the mechanisms underlying uveitis and highlights the potential of the 14-3-3ζ/HO-1 axis as a therapeutic target for the disease. Further research in this area could lead to the development of preventive and therapeutic strategies for uveitis.

The effects of hyaluronan and proteoglycan link protein 1 (HAPLN1) in ameliorating spinal cord injury mediated by Nrf2.

Excessive inflammatory response and oxidative stress (OS) play an important role in the pathogenesis of spinal cord injury (SCI). Balance of inflammation and prevention of OS have been considered an effective strategy for the treatment of SCI. Hyaluronan and proteoglycan link protein 1 (HAPLN1), also known as cartilage link protein, has displayed a wide range of biological and physiological functions in different types of tissues and cells. However, whether HAPLN1 regulates inflammation and OS during SCI is unknown. Therefore, we aimed to examine whether HAPLN1 can have a protective effect on SCI. In this study, both in vitro and in vivo SCI models were established. Nissl staining and terminal deoxynucleotidyl transferase dUTP nick end labeling staining assays were used. Western blotting and enzyme-linked immunosorbent assay were employed to assess the expression of proteins. Our results demonstrate that the administration of HAPLN1 promoted the recovery of motor neurons after SCI by increasing the Basso mouse scale score, increasing the numbers of motor neurons, and preventing apoptosis of spinal cord cells. Additionally, HAPLN1 mitigated OS in spinal cord tissue after SCI by increasing the content of superoxide dismutase SOD and the activity of glutathione peroxidase but reducing the levels of malondialdehyde. Importantly, we found that HAPLN1 stimulated the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway and stimulated the expression of heme oxygenase-1 and nicotinamide adenine dinucleotide phosphate quinone oxidoreductase-1, which mediated the attenuation of HAPLN1 in activation of the NOD-like receptor protein 3 (NLRP3) inflammasome by reducing the levels of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), caspase-1, and interleukin-1β. Correspondingly, in vitro experiments show that the presence of HAPLN1 suppressed the NLRP3 inflammasome and prevented cell injury against H2O2 in PC12 cells. These effects were mediated by the Nrf2/ARE pathway, and inhibition of Nrf2 with ML385 abolished the beneficial effects of HAPLN1. Based on these findings, we conclude that HAPLN1 inhibits the NLRP3 inflammasome through the stimulation of the Nrf2/ARE pathway, thereby suppressing neuroinflammation, enhancing motor neuronal survival, and improving the recovery of nerve function after SCI.

Unlocking the Therapeutic Potential of a Manila Clam-Derived Antioxidant Peptide: Insights into Mechanisms of Action and Cytoprotective Effects against Oxidative Stress.

Reactive oxygen species (ROS) are implicated in various pathological conditions due to their ability to induce oxidative damage to cellular components. In this study, we investigated the antioxidant properties of a peptide isolated from the hydrolysate of Manila clam (Ruditapes philippinarum) muscle. Purification steps yielded RPTE2-2-4, exhibiting potent scavenging activities against DPPH•, HO•, and O2•-, akin to Vitamin C. Structural analysis showed that the isolated peptide, LFKKNLLTL, exhibited characteristics associated with antioxidant activity, including a short peptide length and the presence of aromatic and hydrophobic amino acid residues. Moreover, our study demonstrated the cytoprotective effects of the peptide against H2O2-induced oxidative stress in HepG2 cells. Pretreatment with the peptide resulted in a dose-dependent reduction in intracellular ROS levels and elevation of glutathione (GSH) levels, indicating its ability to modulate cellular defense mechanisms against oxidative damage. Furthermore, the peptide stimulated the expression of the cytoprotective enzyme heme oxygenase-1 (HO-1), further reinforcing its antioxidant properties. Overall, our findings highlight the potential of the Manila clam-derived peptide as a natural antioxidant agent with therapeutic implications for oxidative stress-related diseases. Further investigation into its mechanisms of action and in vivo efficacy is warranted to validate its therapeutic potential.

Activation of heme oxygenase-1 by laminar shear stress ameliorates high glucose-induced endothelial cell and smooth muscle cell dysfunction.

High glucose (HG)-induced endothelial cell (EC) and smooth muscle cell (SMC) dysfunction is critical in diabetes-associated atherosclerosis. However, the roles of heme oxygenase-1 (HO-1), a stress-response protein, in hemodynamic force-generated shear stress and HG-induced metabolic stress remain unclear. This investigation examined the cellular effects and mechanisms of HO-1 under physiologically high shear stress (HSS) in HG-treated ECs and adjacent SMCs. We found that exposure of human aortic ECs to HSS significantly increased HO-1 expression; however, this upregulation appeared to be independent of adenosine monophosphate-activated protein kinase, a regulator of HO-1. Furthermore, HSS inhibited the expression of HG-induced intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and reactive oxygen species (ROS) production in ECs. In an EC/SMC co-culture, compared with static conditions, subjecting ECs close to SMCs to HSS and HG significantly suppressed SMC proliferation while increasing the expression of physiological contractile phenotype markers, such as α-smooth muscle actin and serum response factor. Moreover, HSS and HG decreased the expression of vimentin, an atherogenic synthetic phenotypic marker, in SMCs. Transfecting ECs with HO-1-specific small interfering (si)RNA reversed HSS inhibition on HG-induced inflammation and ROS production in ECs. Similarly, reversed HSS inhibition on HG-induced proliferation and synthetic phenotype formation were observed in co-cultured SMCs. Our findings provide insights into the mechanisms underlying EC-SMC interplay during HG-induced metabolic stress. Strategies to promote HSS in the vessel wall, such as continuous exercise, or the development of HO-1 analogs and mimics of the HSS effect, could provide an effective approach for preventing and treating diabetes-related atherosclerotic vascular complications.

The Bach1/HO-1 pathway regulates oxidative stress and contributes to ferroptosis in doxorubicin-induced cardiomyopathy in H9c2 cells and mice.

Doxorubicin (DOX) is one of the most frequently used chemotherapeutic drugs belonging to the class of anthracyclines. However, the cardiotoxic effects of anthracyclines limit their clinical use. Recent studies have suggested that ferroptosis is the main underlying pathogenetic mechanism of DOX-induced cardiomyopathy (DIC). BTB-and-CNC homology 1 (Bach1) acts as a key role in the regulation of ferroptosis. However, the mechanistic role of Bach1 in DIC remains unclear. Therefore, this study aimed to investigate the underlying mechanistic role of Bach1 in DOX-induced cardiotoxicity using the DIC mice in vivo (DOX at cumulative dose of 20mg/kg) and the DOX-treated H9c2 cardiomyocytes in vitro (1μM). Our results show a marked upregulation in the expression of Bach1 in the cardiac tissues of the DOX-treated mice and the DOX-treated cardiomyocytes. However, Bach1-/- mice exhibited reduced lipid peroxidation and less severe cardiomyopathy after DOX treatment. Bach1 knockdown protected against DOX-induced ferroptosis in both in vivo and in vitro models. Ferrostatin-1 (Fer-1), a potent inhibitor of ferroptosis, significantly alleviated DOX-induced cardiac damage. However, the cardioprotective effects of Bach1 knockdown were reversed by pre-treatment with Zinc Protoporphyrin (ZnPP), a selective inhibitor of heme oxygenase-1(HO-1). Taken together, these findings demonstrated that Bach1 promoted oxidative stress and ferroptosis through suppressing the expression of HO-1. Therefore, Bach1 may present as a promising new therapeutic target for the prevention and early intervention of DOX-induced cardiotoxicity.

Indole-3-carbinol ameliorates ovarian damage in female old mice through Nrf2/HO-1 pathway activation

Ovarian aging leads to infertility and birth defects. We aimed to clarify the role of Indole-3-carbinol (I3C) in resistance to oxidative stress, apoptosis, and fibrosis in ovarian aging. I3C was administered via intraperitoneal injection for 3 weeks in young or old mice. Immunohistochemistry; Masson, Sirius red, and TUNEL staining; follicle counting; estrous cycle analysis; and Western blotting were used for validating the protective effect of I3C against ovarian senescence. Human granulosa-like tumor cell line and primary granulosa cells were used for in vitro assay. The results indicated that I3C inhibited ovarian fibrosis and apoptosis while increasing the number of primordial follicles. Mechanistic studies have shown that I3C promoted the nuclear translocation of nuclear factor-erythroid 2-related factor (Nrf2) and upregulated the expression of heme oxygenase 1 (HO-1). Additionally, I3C increased cell viability and decreased lactate dehydrogenase, malondialdehyde, reactive oxygen species and JC-1 levels. Furthermore, the antioxidant effect of I3C was found to be dependent on the activation of Nrf2 and HO-1, as demonstrated by the disappearance of the effect upon inhibition of Nrf2 expression. In conclusion, I3C can alleviate the ovarian damage caused by aging and may be a protective agent to delay ovarian aging.

Suppression of inflammation in ulcerative colitis rats by avocado and pomegranate

BackgroundPomegranate seed oil (PSO) and avocado seed oil (ASO) are natural polyphenols with established anti-inflammatory activity. PurposeThis study aimed to investigate the molecular mechanisms underlying the therapeutic efficacy of PSO and ASO in experimental ulcerative colitis (UC) with reference to sulfasalazine (SLZ). MethodsEighty male albino rats were divided equally into 8 groups; Normal, PSO, ASO, SLZ, UC-control, (UC+PSO), (UC+ASO) and (UC+SLZ) groups. Colitis was induced by intra-rectal injection of acetic acid. PSO (0.5ml/ 200g), ASO (1ml/ 250g) and SLZ (100mg/kg) were administered orally once/day for 14 days, 24h after colitis induction. Colitis was evaluated by measuring disease activity index (DAI), colon weight/length ratio and histologic inflammatory score. Vascular endothelial growth factor receptor-2 (VEGFR-2), colonic macrophage migration inhibitory factor (MIF), and malondialdehyde (MDA) were determined. Colonic gene expression of TNF-α, VEGF and heme oxygenase-1 (HO-1) were also estimated. ResultsPSO and ASO treatments to UC rats significantly reduced DAI, weight/length ratio, VEGFR-2, and colon histologic inflammatory score versus UC-controls. ASO significantly suppressed MIF levels and TNF-α expression greater than PSO. However, PSO was more significant than ASO in reducing MDA levels and up-regulating HO-1 expression. Both oils significantly down-regulated VEGF expression. The obtained biochemical and histological changes induced by UC were nearly corrected by SLZ. ConclusionThe proved beneficial effect of PSO and ASO as anti-inflammatory, anti-angiogenic, and antioxidant in UC rats could be mediated by suppression of TNF-α, VEGF, and MIF and up-regulation of HO-1.

A Mechanistic Study of the Osteogenic Effect of Arecoline in an Osteoporosis Model: Inhibition of Iron Overload-Induced Osteogenesis by Promoting Heme Oxygenase-1 Expression.

Iron overload-associated osteoporosis presents a significant challenge to bone health. This study examines the effects of arecoline (ACL), an alkaloid found in areca nut, on bone metabolism under iron overload conditions induced by ferric ammonium citrate (FAC) treatment. The results indicate that ACL mitigates the FAC-induced inhibition of osteogenesis in zebrafish larvae, as demonstrated by increased skeletal mineralization and upregulation of osteogenic genes. ACL attenuates FAC-mediated suppression of osteoblast differentiation and mineralization in MC3T3-E1 cells. RNA sequencing analysis suggests that the protective effects of ACL are related to the regulation of ferroptosis. We demonstrate that ACL inhibits ferroptosis, including oxidative stress, lipid peroxidation, mitochondrial damage, and cell death under FAC exposure. In this study, we have identified heme oxygenase-1 (HO-1) as a critical mediator of ACL inhibiting ferroptosis and promoting osteogenesis, which was validated by HO-1 knockdown and knockout experiments. The study links ACL to HO-1 activation and ferroptosis regulation in the context of bone metabolism. These findings provide new insights into the mechanisms underlying the modulation of osteogenesis by ACL. Targeting the HO-1/ferroptosis axis is a promising therapeutic approach for treating iron overload-induced bone diseases.

Esculin induces endoplasmic reticulum stress and drives apoptosis and ferroptosis in colorectal cancer via PERK regulating eIF2α/CHOP and Nrf2/HO-1 cascades

Ethnopharmacological relevanceCortex fraxini (also known as Qinpi), the bark of Fraxinus rhynchophylla Hance and Fraxinus stylosa Lingelsh, constitutes a crucial component in several traditional Chinese formulas (e.g., Baitouweng Tang, Jinxiao Formula, etc.) and has demonstrated efficacy in alleviating intestinal carbuncle and managing diarrhea. Cortex fraxini has demonstrated commendable anticancer activity in the realm of Chinese ethnopharmacology; nevertheless, the underlying mechanisms against colorectal cancer (CRC) remain elusive. Aim of the studyEsculin, an essential bioactive compound derived from cortex fraxini, has recently garnered attention for its ability to impede viability and induce apoptosis in cancer cells. This investigation aims to assess the therapeutic potential of esculin in treating CRC and elucidate the underlying mechanisms. Materials and methodsThe impact of esculin on CRC cell viability was assessed using CCK-8 assay, Annexin V/PI staining, and Western blotting. Various cell death inhibitors, along with DCFH-DA, ELISA, biochemical analysis, and Western blotting, were employed to delineate the modes through which esculin induces HCT116 cells death. Inhibitors and siRNA knockdown were utilized to analyze the signaling pathways influenced by esculin. Additionally, an azomethane/dextran sulfate sodium (AOM/DSS)-induced in vivo CRC mouse model was employed to validate esculin's potential in inhibiting tumorigenesis and to elucidate its underlying mechanisms. ResultsEsculin significantly suppressed the viability of various CRC cell lines, particularly HCT116 cells. Investigation with diverse cell death inhibitors revealed that esculin-induced cell death was associated with both apoptosis and ferroptosis. Furthermore, esculin treatment triggered cellular lipid peroxidation, as evidenced by elevated levels of malondialdehyde (MDA) and decreased levels of glutathione (GSH), indicative of its propensity to induce ferroptosis in HCT116 cells. Enhanced protein levels of protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) and p-eIF2α suggested that esculin induced cellular endoplasmic reticulum (ER) stress, subsequently activating the Nrf2/ARE signaling pathway and initiating the transcriptional expression of heme oxygenase (HO)-1. Esculin-induced excessive expression of HO-1 could potentially lead to iron overload in HCT116 cells. Knockdown of Ho-1 significantly attenuated esculin-induced ferroptosis, underscoring HO-1 as a critical mediator of esculin-induced ferroptosis in HCT116 cells. Furthermore, utilizing an AOM/DSS-induced colorectal cancer mouse model, we validated that esculin potentially inhibits the onset and progression of colon cancer by inducing apoptosis and ferroptosis in vivo. ConclusionsThese findings provide comprehensive insights into the dual induction of apoptosis and ferroptosis in HCT116 cells by esculin. The activation of the PERK signaling pathway, along with modulation of downstream eIF2α/CHOP and Nrf2/HO-1 cascades, underscores the mechanistic basis supporting the clinical application of esculin on CRC treatment.

FGF17 protects cerebral ischemia reperfusion-induced blood-brain barrier disruption via FGF receptor 3-mediated PI3K/AKT signaling pathway

Maintaining blood-brain barrier (BBB) integrity is critical components of therapeutic approach for ischemic stroke. Fibroblast growth factor 17 (FGF17), a member of FGF8 superfamily, exhibits the strongest expression throughout the wall of all major arteries during development. However, its molecular action and potential protective role on brain endothelial cells after stroke remains unclear. Here, we observed reduced levels of FGF17 in the serum of patients with ischemic stroke, as well as in the brains of mice subjected to middle cerebral artery occlusion (MCAO) injury and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced brain microvascular endothelial cells (bEnd.3) cells. Moreover, treatment with exogenous recombinant human FGF17 (rhFGF17) decreased infarct volume, improved neurological deficits, reduced Evans Blue leakage and upregulated the expression of tight junctions in MCAO-injured mice. Meanwhile, rhFGF17 increased cell viability, enhanced trans-endothelial electrical resistance, reduced sodium fluorescein leakage, and alleviated reactive oxygen species (ROS) generation in OGD/R-induced bEnd.3 cells. Mechanistically, the treatment with rhFGF17 resulted in nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear accumulation and upregulation of heme oxygenase-1 (HO-1) expression. Additionally, based on in-vivo and in-vitro research, rhFGF17 exerted protective effects against ischemia/reperfusion (I/R) -induced BBB disruption and endothelial cell apoptosis through the activation of the FGF receptor 3/PI3K/AKT signaling pathway. Overall, our findings indicated that FGF17 may hold promise as a novel therapeutic strategy for ischemic stroke patients.