Heme oxygenase-1: its therapeutic roles in inflammatory diseases

Role of mitochondrial homeostasis in D-galactose-induced cardiovascular ageing from bench to bedside

Ageing is an inevitable phenomenon which affects the cellular to the organism level in the progression of the time. Oxidative stress and inflammation are now widely regarded as the key processes involved in the aging process, which may then cause significant harm to mitochondrial DNA, leading to apoptosis. Normal circulatory function is a significant predictor of disease-free life expectancy. Indeed, disorders affecting the cardiovascular system, which are becoming more common, are the primary cause of worldwide morbidity, disability, and mortality. Cardiovascular aging may precede or possibly underpin overall, age-related health decline. Numerous studies have foundmitochondrial mechanistc approachplays a vital role in the in the onset and development of aging. The D-galactose (D-gal)-induced aging model is well recognized and commonly used in the aging study. In this review we redeposit the association of the previous and current studies on mitochondrial homeostasis and its underlying mechanisms in D-galactose cardiovascular ageing. Further we focus the novel and the treatment strategies to combat the major complication leading to the cardiovascular ageing.

Exploring the Comprehensive Neuroprotective and Anticancer Potential of Afzelin

Neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, Huntington's disease, and others) and cancer, seemingly disparate in their etiology and manifestation, exhibit intriguing associations in certain cellular and molecular processes. Both cancer and neurodegenerative diseases involve the deregulation of cellular processes such as apoptosis, proliferation, and DNA repair and pose a significant global health challenge. Afzelin (kaempferol 3-O-rhamnoside) is a flavonoid compound abundant in various plant sources. Afzelin exhibits a diverse range of biological activities, offering promising prospects for the treatment of diseases hallmarked by oxidative stress and deregulation of cell death pathways. Its protective potential against oxidative stress is also promising for alleviating the side effects of chemotherapy. This review explores the potential therapeutic implications of afzelin, including its capacity to mitigate oxidative stress, modulate inflammation, and promote cellular regeneration in neurodegenerative and cancer diseases.

Anti-inflammatory effects of cold atmospheric plasma irradiation on the THP-1 human acute monocytic leukemia cell line

Cold atmospheric plasma (CAP) has been studied and clinically applied to treat chronic wounds, cancer, periodontitis, and other diseases. CAP exerts cytotoxic, bactericidal, cell-proliferative, and anti-inflammatory effects on living tissues by generating reactive species. Therefore, CAP holds promise as a treatment for diseases involving chronic inflammation and bacterial infections. However, the cellular mechanisms underlying these anti-inflammatory effects of CAP are still unclear. Thus, this study aimed to elucidate the anti-inflammatory mechanisms of CAP in vitro. The human acute monocytic leukemia cell line, THP-1, was stimulated with lipopolysaccharide and irradiated with CAP, and the cytotoxic effects of CAP were evaluated. Time-course differentiation of gene expression was analyzed, and key transcription factors were identified via transcriptome analysis. Additionally, the nuclear localization of the CAP-induced transcription factor was examined using western blotting. The results indicated that CAP showed no cytotoxic effects after less than 70 s of irradiation and significantly inhibited interleukin 6 (IL6) expression after more than 40 s of irradiation. Transcriptome analysis revealed many differentially expressed genes (DEGs) following CAP irradiation at all time points. Cluster analysis classified the DEGs into four distinct groups, each with time-dependent characteristics. Gene ontology and gene set enrichment analyses revealed CAP-induced suppression of IL6 production, other inflammatory responses, and the expression of genes related to major histocompatibility complex (MHC) class II. Transcription factor analysis suggested that nuclear factor erythroid 2-related factor 2 (NRF2), which suppresses intracellular oxidative stress, is the most activated transcription factor. Contrarily, regulatory factor X5, which regulates MHC class II expression, is the most suppressed transcription factor. Western blotting revealed the nuclear localization of NRF2 following CAP irradiation. These data suggest that CAP suppresses the inflammatory response, possibly by promoting NRF2 nuclear translocation.

The Antimalarial Drug Artesunate Mediates Selective Cytotoxicity by Upregulating HO-1 in Melanoma Cells

Despite great efforts to develop new therapeutic strategies to combat melanoma, the prognosis remains rather poor. Artesunate (ART) is an antimalarial drug displaying anti-cancer effects in vitro and in vivo. In this in vitro study, we investigated the selectivity of ART on melanoma cells. Furthermore, we aimed to further elucidate the mechanism of the drug with a focus on the role of iron, the induction of oxidative stress and the implication of the enzyme heme oxygenase 1 (HO-1). ART treatment decreased the cell viability of A375 melanoma cells while it did not affect the viability of normal human dermal fibroblasts, used as a model for normal (healthy) cells. ART's toxicity was shown to be dependent on intracellular iron and the drug induced high levels of oxidative stress as well as upregulation of HO-1. Melanoma cells deficient in HO-1 or treated with a HO-1 inhibitor were less sensitive towards ART. Taken together, our study demonstrates that ART induces oxidative stress resulting in the upregulation of HO-1 in melanoma cells, which subsequently triggers the effect of ART's own toxicity. This new finding that HO-1 is involved in ART-mediated toxicity may open up new perspectives in cancer therapy.

The Triterpenoid Nrf2 Activator, CDDO-Me, Decreases Neutrophil Senescence in a Murine Model of Joint Damage

The synthetic 2-cyano-3,12-dioxo-oleana-1,9(11)-dien-28-oic acid methyl ester (CDDO-Me) is a potent activator of the erythroid 2-p45-derived factor 2, Nrf2, a leucine-zipper regulator of the antioxidant response. Herein, we investigated the effect of CDDO-Me on neutrophil function in a murine model of joint damage. Collagenase-induced osteoarthritis (CIOA) was initiated by the intra-articular injection of collagenase in the knee-joint cavity of Balb/c mice. CDDO-Me was administrated intra-articularly twice a week starting at day 7 post-CIOA, and its effect was evaluated at day 14. Neutrophils in blood and bone marrow (BM), cell apoptosis, necrosis, expression of C-X-C chemokine receptor 4 (CXCR4), beta-galactosidase (β-Gal), and Nrf2 levels were measured by flow cytometry. In vitro, CDDO-Me promoted cell survival, reduced cell necrosis, and increased Nrf2 levels by 1.6 times. It decreased surface CXCR4 expression and reduced the frequency of senescent β-Gal+CXCR4+ neutrophils by three times. In vivo, the degree of knee-joint damage in CIOA was correlated with upregulated CXCR4 on CD11b+ neutrophils. CDDO-Me improved the disease histological score, increased the levels of Nrf2, and downregulated surface CXCR4 on mature BM cells. Our data suggest that CDDO-Me may act as a potent regulator of neutrophil senescence during the progression of knee-joint damage.

Protective Effect of Glycomacropeptide on the Inflammatory Response of U937 Macrophages

Macrophages play crucial roles in inflammation and oxidative stress associated with noncommunicable diseases, such as cardiovascular diseases, diabetes, and cancer. Glycomacropeptide (GMP) is a bioactive peptide derived from milk κ-casein that contains abundant sialic acid and has shown anti-inflammatory, antioxidative, anti-obesity, and anti-diabetic properties when is orally administered. The aim of this study was to evaluate the effect of GMP on the regulation of the inflammatory response in human macrophages and the participation of sialic acid in this activity. GMP pretreatment decreased by 35%, 35%, and 49% the production of nitrites, interleukin (IL)-1β, and tumor necrosis factor (TNF)-α, respectively, in activated human macrophages U937. The same effect was obtained when cells were pretreated with asialo GMP, and no change on the gene expression of the lectins associated with the recognition of sialic acids, SIGLEC5, 7, and 9, was induced by GMP on macrophages, which suggests that sialic acid might not be involved in this immunoregulatory effect. Interestingly, GMP increased 8.9- and 3.5-fold the gene expression of the canonical anti-inflammatory protein SOCS3 and the antioxidant enzyme HMOX1, respectively, in U937 cells. Thus, GMP exerts anti-inflammatory and antioxidative activities on activated macrophages in a sialic acid-independent manner, which might be related to its in vivo reported bioactivity.

Normal and Pathological NRF2 Signalling in the Central Nervous System

The nuclear factor erythroid 2-related factor 2 (NRF2) was originally described as a master regulator of antioxidant cellular response, but in the time since, numerous important biological functions linked to cell survival, cellular detoxification, metabolism, autophagy, proteostasis, inflammation, immunity, and differentiation have been attributed to this pleiotropic transcription factor that regulates hundreds of genes. After 40 years of in-depth research and key discoveries, NRF2 is now at the center of a vast regulatory network, revealing NRF2 signalling as increasingly complex. It is widely recognized that reactive oxygen species (ROS) play a key role in human physiological and pathological processes such as ageing, obesity, diabetes, cancer, and neurodegenerative diseases. The high oxygen consumption associated with high levels of free iron and oxidizable unsaturated lipids make the brain particularly vulnerable to oxidative stress. A good stability of NRF2 activity is thus crucial to maintain the redox balance and therefore brain homeostasis. In this review, we have gathered recent data about the contribution of the NRF2 pathway in the healthy brain as well as during metabolic diseases, cancer, ageing, and ageing-related neurodegenerative diseases. We also discuss promising therapeutic strategies and the need for better understanding of cell-type-specific functions of NRF2 in these different fields.

Oxyberberine, a novel HO-1 agonist, effectively ameliorates oxidative stress and inflammatory response in LPS/D-GalN induced acute liver injury mice via coactivating erythrocyte metabolism and Nrf2 signaling pathway

Oxyberberine (OBB), a main gut-mediated metabolite of Phellodendron chinense Cortex (PC), exhibits prominent protective property against acute liver injury (ALI). Heme oxygenase-1 (HO-1) is a vital molecule in attenuating acute and chronic liver injury for its prominent anti-oxidative injury and anti-inflammation properties. The present study was performed to investigate the hepatoprotective role of OBB through HO-1 signaling pathway in lipopolysaccharide/D-galactosamine (LPS/D-GalN) induced ALI. Our results indicated that PC treatment improved survival rate and its metabolite OBB evidently improved histopathological deteriorations and liver function. Additionally, OBB dramatically ameliorated hepatic oxidative stress and inflammation. Besides, OBB exerted remarkable HO-1 agonistic activity, even be comparable to hemin (a HO-1 inducer), as evidenced by increased HO-1 level, carbon monoxide and bilirubin activities, which are the markers of erythrocyte metabolism. Moreover, OBB modulated the parameters of inflammation and oxidative stress through HO-1 dependent pathway. Beyond this, OBB also notably suppressed the translocation of p65, enhanced antioxidation defense genes expressions, promoted the degradation of Kelch-like ECH-associated protein 1 (Keap1) and the nuclear translocation of nuclear factor-erythroid-2-related factor 2 (Nrf2). In conclusion, OBB could be the principle active metabolite substance of PC and exert excellent hepatoprotective effects via inducing HO-1 through coactivation of erythrocyte metabolism and Nrf2/HO-1 pathway.

Heme oxygenase-1 modulates brain inflammation and apoptosis in mice with angiostrongyliasis

The rat nematode lungworm Angiostrongylus cantonensis undergoes obligatory intracerebral migration in its hosts and causes eosinophilic meningitis or meningoencephalitis. Heme oxygenase 1 (HO-1) has several cytoprotective properties such as anti-oxidative, anti-inflammatory, and anti-apoptotic effects. HO-1 in brain tissues was induced in A. cantonensis-infected group and showed positive modulation in cobalt protoporphyrin (CoPP)-treated groups. Assay methods for the therapeutic effect include western blot analysis, enzyme-linked immunosorbent assay, gelatin zymography, blood-brain barrier permeability evaluation and eosinophil count in cerebrospinal fluid. The combination of albendazole (ABZ) and CoPP significantly decreased pro-inflammatory cytokines, tumor necrosis factor-α, interleukin (IL)-1β, IL-5, and IL-33 but significantly increased anti-inflammatory cytokines IL-10 and transforming growth factor-β. In addition, worm recovery, matrix metalloproteinase-9, BBB permeability, and eosinophil counts were decreased in the ABZ and CoPP co-treated groups. Induction of HO-1 with CoPP strongly inhibited the protein levels of caspase-3 and increased the induction of annexin-V and B-cell leukemia 2. Thus, co-treatment with ABZ and CoPP prevented A. cantonensis-induced eosinophilic meningoencephalitis and its anti-apoptotic effect by promoting HO-1 signaling prior to BBB dysfunction. HO-1 induction might be a therapeutic modality for eosinophilic meningoencephalitis.

COVID-19-Associated acute respiratory distress syndrome (CARDS): Mechanistic insights on therapeutic intervention and emerging trends

AIMS

The novel Coronavirus disease 2019 (COVID-19) has caused great distress worldwide. Acute respiratory distress syndrome (ARDS) is well familiar but when it happens as part of COVID-19 it has discrete features which are unmanageable. Numerous pharmacological treatments have been evaluated in clinical trials to control the clinical effects of CARDS, but there is no assurance of their effectiveness.

MATERIALS AND METHODS

A systematic review of the literature of the Medline, Scopus, Bentham, PubMed, and EMBASE (Elsevier) databases was examined to understand the novel therapeutic approaches used in COVID-19-Associated Acute Respiratory Distress Syndrome and their outcomes.

KEY FINDINGS

Current therapeutic options may not be enough to manage COVID-19-associated ARDS complications in group of patients and therefore, the current review has discussed the pathophysiological mechanism of COVID-19-associated ARDS, potential pharmacological treatment and the emerging molecular drug targets.

SIGNIFICANCE

The rationale of this review is to talk about the pathophysiology of CARDS, potential pharmacological treatment and the emerging molecular drug targets. Currently accessible treatment focuses on modulating immune responses, rendering antiviral effects, anti-thrombosis or anti-coagulant effects. It is expected that considerable number of studies conducting globally may help to discover effective therapies to decrease mortality and morbidity occurring due to CARDS. Attention should be also given on molecular drug targets that possibly will help to develop efficient cure for COVID-19-associated ARDS.

The Protective Role of the Heme Catabolic Pathway in Hepatic Disorders

Significance: As the central metabolic organ, the liver is exposed to a variety of potentially cytotoxic, proinflammatory, profibrotic, and carcinogenic stimuli. To protect the organism from these deleterious effects, the liver has evolved a number of defense systems, which include antioxidant substrates and enzymes, anti-inflammatory tools, enzymatic biotransformation systems, and metabolic pathways. Recent Advances: One of the pivotal systems that evolved during phylogenesis was the heme catabolic pathway. Comprising the important enzymes heme oxygenase and biliverdin reductase, this complex pathway has a number of key functions including enzymatic activities, but also cell signaling, and DNA transcription. It further generates two important bile pigments, biliverdin and bilirubin, as well as the gaseous molecule carbon monoxide. These heme degradation products have potent antioxidant, immunosuppressive, and cytoprotective effects. Recent data suggest that the pathway participates in the regulation of metabolic and hormonal processes implicated in the pathogenesis of hepatic and other diseases. Critical Issues: This review discusses the impact of the heme catabolic pathway on major liver diseases, with particular focus on the involvement of cellular targeting and signaling in the pathogenesis of these conditions. Future Directions: To utilize the biological consequences of the heme catabolic pathway, several unique therapeutic strategies have been developed. Research indicates that pharmaceutical, nutraceutical, and lifestyle modifications positively affect the pathway, delivering potentially long-term clinical benefits. However, further well-designed studies are needed to confirm the clinical benefits of these approaches. Antioxid. Redox Signal. 35, 734-752.

Anti-Inflammatory Effects of Heat-Processed Artemisia capillaris Thunberg by Regulating IκBα/NF-κB Complex and 15-PGDH in Mouse Macrophage Cells

Growing evidence suggests that dietary nutrients in herbs and plants are beneficial in improving inflammatory disorders. Artemisia capillaris Thunberg (AC) is a traditional herbal medicine widely used in East Asia to treat pain, hepatotoxicity, and inflammatory disorders. Heat processing is a unique pharmaceutical method used in traditional herbal medicine to enhance the pharmacological effects and safety of medicinal plants. This study demonstrates the anti-inflammatory effects of heat-processed AC (HPAC) in lipopolysaccharide- (LPS-) treated mouse macrophage cells. HPAC reduced LPS-induced inflammatory mediators such as IL-6, IL-1β, TNF-α, NO, and PGE2 in RAW 264.7 cells. Interestingly, 15-PGDH appears to play a pivotal role rather than COX-2 and mPGES-1 when HPAC regulated PGE2 levels. Meanwhile, HPAC showed anti-inflammatory effects by blocking IκBα phosphorylation and NF-κB nuclear translocalization. Also, we found that HO-1 upregulation was mediated by the mitogen-activated protein kinase (MAPK) pathways in HPAC-treated RAW 264.7 cells. And, in RAW 264.7 cells challenged with LPS, HPAC restored HO-1 expression, leading to NF-κB inhibition. Through further experiments using specific MAPK inhibitors, we found that, in response to LPS, the phosphorylated IκBα and activated NF-κB were attenuated by p38 MAPK/HO-1 pathway. Therefore, HPAC targeting both the IκBα/NF-κB complex and 15-PGDH may be considered as a potential novel anti-inflammatory agent derived from a natural source.

Heme Oxygenase-1 Contributes to Both the Engulfment and the Anti-Inflammatory Program of Macrophages during Efferocytosis

Heme oxygenase-1 (HO-1) plays a vital role in the catabolism of heme and yields equimolar amounts of biliverdin, carbon monoxide, and free iron. We report that macrophages engulfing either the low amount of heme-containing apoptotic thymocytes or the high amount of heme-containing eryptotic red blood cells (eRBCs) strongly upregulate HO-1. The induction by apoptotic thymocytes is dependent on soluble signals, which do not include adenylate cyclase activators but induce the p38 mitogen-activated protein (MAP) kinase pathway, while in the case of eRBCs, it is cell uptake-dependent. Both pathways might involve the regulation of BTB and CNC homology 1 (BACH1), which is the repressor transcription regulator factor of the HO-1 gene. Long-term continuous efferocytosis of apoptotic thymocytes is not affected by the loss of HO-1, but that of eRBCs is inhibited. This latter is related to an internal signaling pathway that prevents the efferocytosis-induced increase in Rac1 activity. While the uptake of apoptotic cells suppressed the basal pro-inflammatory cytokine production in wild-type macrophages, in the absence of HO-1, engulfing macrophages produced enhanced amounts of pro-inflammatory cytokines. Our data demonstrate that HO-1 is required for both the engulfment and the anti-inflammatory response parts of the efferocytosis program.

Anti-Inflammatory Potential Exhibited by Amomum subulatum Fruits Mitigates Experimentally Induced Acute and Chronic Inflammation in Mice: Evaluation of Antioxidant Parameters, Pro-Inflammatory Mediators and HO-1 Pathway

OBJECTIVE

Conventional anti-inflammatory drugs are associated with serious adverse effects which bring about an ever-increasing demand to supersede them with natural and safe anti-inflammatory agents. Hence, the prime objective of this study was to evaluate the anti- inflammatory potential of an underutilized culinary spice "Amomum subulatum".

METHODS

To assess anti-inflammatory activity of MEAS, acute and chronic inflammation studies were carried out in carrageenan and formalin induced mice paw edema models respectively. Paw volume was measured by vernier caliper. Status of antioxidant enzymes and oxidative stress markers were determined in paw tissue homogenates following standard protocols. Histopathology and immunohistochemistry analysis of paw tissue samples were also performed. Levels of proinflammatory cytokines in serum were quantified by ELISA. Effect of MEAS on vascular permeability was evaluated by evans blue dye extravasation assay. Involvement of heme oxygenase (HO)-1 pathway in anti-inflammatory action of MEAS was investigated by pretreating mice with zinc protoporphyrin (ZnPP) IX, a specific inhibitor of HO-1.

RESULTS

MEAS administration significantly reduced paw edema, as evidenced by paw volume measurement and histopathology analysis. Additionally, pretreatment with MEAS markedly reduced vascular permeability, serum proinflammatory cytokine levels, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). Further, the anti-inflammatory mechanism of MEAS showed the involvement of HO-1 pathway when HO-1 was inhibited by ZnPPIX.

CONCLUSION

Our results manifested strong anti-inflammatory activity of MEAS, suggesting its potential use as a therapeutic alternative for treating inflammatory disorders.

Hydrogen Sulfide and its Interaction with Other Players in Inflammation

Hydrogen sulfide (H₂S) plays a vital role in human physiology and in the pathophysiology of several diseases. In addition, a substantial role of H₂S in inflammation has emerged. This chapter will discuss the involvement of H₂S in various inflammatory diseases. Furthermore, the contribution of reactive oxygen species (ROS), adhesion molecules, and leukocyte recruitment in H₂S-mediated inflammation will be discussed. The interrelationship of H₂S with other gasotransmitters in inflammation will also be examined. There is mixed literature on the contribution of H₂S to inflammation due to studies reporting both pro- and anti-inflammatory actions. These apparent discrepancies in the literature could be resolved with further studies.

Anti-Inflammatory Activity of Kurarinone Involves Induction of HO-1 via the KEAP1/Nrf2 Pathway

Kurarinone, a flavonoid isolated from the roots of Sophora flavescens, was suggested to exert potent antioxidant and immunosuppressive effects. However, the underlying mechanisms remain unclear. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key transcription factor that regulates the antioxidant defense system with anti-inflammatory activity. In the present study, we demonstrated that kurarinone activated Nrf2 and increased the expression of antioxidant enzymes, including heme oxygenase-1 (HO-1). Mechanistically, kurarinone downregulated the expression of kelch-like ECH-associated protein 1 (KEAP1), subsequently leading to the activation of Nrf2. Kurarinone also inhibited the expression of the inflammatory cytokine, interleukin (IL)-1β, and inducible nitric oxide synthase (iNos) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. The overexpression of HO-1 suppressed the LPS-induced production of inflammatory mediators in RAW264.7 cells, and the immunosuppressive effects of kurarinone were partially inhibited by a treatment with Tin Protomorphyrin IX (TinPPIX), an inhibitor of HO-1. These results indicate that kurarinone activates the KEAP1/Nrf2 pathway to induce HO-1 expression, thereby exerting immunosuppressive effects.

Therapeutic Efficacy of Antioxidants in Ameliorating Obesity Phenotype and Associated Comorbidities

Obesity has been a worldwide epidemic for decades. Despite the abundant increase in knowledge regarding the etiology and pathogenesis of obesity, the prevalence continues to rise with estimates predicting considerably higher numbers by the year 2030. Obesity is characterized by an abnormal lipid accumulation, however, the physiological consequences of obesity are far more concerning. The development of the obesity phenotype constitutes dramatic alterations in adipocytes, along with several other cellular mechanisms which causes substantial increase in systemic oxidative stress mediated by reactive oxygen species (ROS). These alterations promote a chronic state of inflammation in the body caused by the redox imbalance. Together, the systemic oxidative stress and chronic inflammation plays a vital role in maintaining the obese state and exacerbating onset of cardiovascular complications, Type II diabetes mellitus, dyslipidemia, non-alcoholic steatohepatitis, and other conditions where obesity has been linked as a significant risk factor. Because of the apparent role of oxidative stress in the pathogenesis of obesity, there has been a growing interest in attenuating the pro-oxidant state in obesity. Hence, this review aims to highlight the therapeutic role of antioxidants, agents that negate pro-oxidant state of cells, in ameliorating obesity and associated comorbidities. More specifically, this review will explore how various antioxidants target unique and diverse pathways to exhibit an antioxidant defense mechanism.

Low molecular weight blue mussel hydrolysates inhibit adipogenesis in mouse mesenchymal stem cells through upregulating HO-1/Nrf2 pathway

Blue mussel proteins are a good source of bioactive peptides. In this study, blue mussel hydrolysate (BMH) with anti-adipogenic effect in mouse mesenchymal stem cells (mMSC) was produced by peptic hydrolysis at 1:500 of pepsin/substrate ratio for 120 min. Additionally, BMH with below 1 kDa (BMH < 1 kDa) showed the highest anti-adipogenic effect in mMSC. BMH < 1 kDa increased lipolysis and down-regulated adipogenic transcription factors including peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein 1 (SREBP1). Generation of intracellular reactive oxygen species during adipogenesis was markedly decreased by BMH < 1 kDa treatment, which is attributed to the up-regulation of heme oxygenase-1 (HO-1) through Nrf2 translocation into the nucleus. Moreover, ZnPP, HO-1 inhibitor, treatment abolished BMH < 1 kDa-mediated HO-1 expression and anti-adipogenic effect in mMSCs through down-regulating adipogenic transcription factors. Taken together, BMH < 1 kDa may be a potential ingredient of nutraceuticals and/or functional foods in ameliorating obesity.

Fruit Extract of Pithecellobium dulce (FPD) ameliorates carrageenan-induced acute inflammatory responses via regulating pro-inflammatory mediators

Unravelling the precise mechanisms underlying the anti-inflammatory action of fruit extract of Pithecellobium dulce (FPD) is quite complex. Hence the prime approach of this particular study is to unveil intriguing insights to its possible anti-inflammatory mechanisms. Anti-inflammatory effects of FPD were determined against experimentally induced acute and chronic inflammation in mice paw edema models. Administration of FPD significantly reduced the acute and chronic inflammation via regulating pro-inflammatory mediators such as pro-inflammatory cytokines (TNF-α, IL-6, and IL-1ß), Cycloxygenase 2 (COX-2), and inducible nitric oxide synthase (iNOS) compared to control group. The overall results suggest that FPD mitigates inflammation by regulating the inflammatory mediators. PRACTICAL APPLICATIONS: Fruit of Pithecellobium dulce is comestible and has been widely distributed in Asian pacific region. Non-steroidal anti-inflammatory drugs (NSAIDS) are among the most conventional treatment strategy against pain and inflammation. Although, chronic use of NSAIDS are associated with severe side effects such as gastrointestinal irritation, hepatic injury, excessive bleeding, and cardiovascular disorders. Hence identification of more effective complementary and alternative therapeutic approach from natural resources with fewer side effects could improve the quality of life of those receiving NSAIDS. Administration of fruit extract of Pithecellobium dulce ameliorates carrageenan-induced acute inflammatory responses, as evidenced by paw edema measurement, expression of antioxidant enzymes such as glutathionine, super oxide dismutase, pro-inflammatory cytokine analysis (IL-1β, IL-6, and TNF-α), vascular permeability measurement, expression of COX-2 and iNOS. Further, confirmed the involvement of HO-1 pathway in anti-inflammatory action of FPD. The outcome of this present investigation could have a broad range of applications in alleviating inflammatory disorders.

Innate immunity orchestrates the mobilization and homing of hematopoietic stem/progenitor cells by engaging purinergic signaling-an update

Bone marrow (BM) as an active hematopoietic organ is highly sensitive to changes in body microenvironments and responds to external physical stimuli from the surrounding environment. In particular, BM tissue responds to several cues related to infections, strenuous exercise, tissue/organ damage, circadian rhythms, and physical challenges such as irradiation. These multiple stimuli affect BM cells to a large degree through a coordinated response of the innate immunity network as an important guardian for maintaining homeostasis of the body. In this review, we will foc++us on the role of purinergic signaling and innate immunity in the trafficking of hematopoietic stem/progenitor cells (HSPCs) during their egression from the BM into peripheral blood (PB), as seen along pharmacological mobilization, and in the process of homing and subsequent engraftment into BM after hematopoietic transplantation. Innate immunity mediates these processes by engaging, in addition to certain peptide-based factors, other important non-peptide mediators, including bioactive phosphosphingolipids and extracellular nucleotides, as the main topic of this review. Elucidation of these mechanisms will allow development of more efficient stem cell mobilization protocols to harvest the required number of HSPCs for transplantation and to accelerate hematopoietic reconstitution in transplanted patients.

Contribution of cholinergic system and Nrf2/HO-1 signaling to the anti-amnesic action of 7-fluoro-1,3-diphenylisoquinoline-1-amine in mice

The isoquinoline 7-fluoro-1,3-diphenylisoquinoline-1-amine (FDPI) has been studied due to its multitarget properties, such as modulation of GABAergic and glutamatergic systems, antioxidant, and anti-inflammatory. This study investigated the contribution of oxidative stress, nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/heme oxygenase (HO-1) signaling, and the cholinergic system to the anti-amnesic action of FDPI in mice. Adult male Swiss mice received FDPI for 5 days (5-25 mg/kg, i.g.); the animals received scopolamine (1 mg/kg, i.p) from day 3-5. The vehicle-control group was carried out. Afterward, mice performed object recognition tests (ORTs). Scopolamine induced amnesia and cholinergic dysfunction by increasing the acetylcholinesterase (AChE) activity and content, decreasing the muscarinic M1 receptor levels in the prefrontal cortex and hippocampus of mice. This study reveals that scopolamine altered oxidative stress parameters differently in the prefrontal cortex and hippocampus of mice. Whereas the prefrontal cortex was susceptible to oxidative stress, none of the parameters evaluated was altered in the hippocampus of scopolamine-treated mice. FDPI at doses of 10 and 25 mg/kg had an anti-amnesic effect in the ORT tests. FDPI 10 mg/kg reversed the increase in the AChE activity and content, oxidative stress parameters, and modulated Nrf2/HO-1 signaling in the prefrontal cortex of scopolamine-exposed mice. Pearson's correlation analyses reinforced the contribution of the prefrontal cortical cholinergic system, oxidative stress as well as Nrf2/HO-1 signaling in the anti-amnesic effect of FDPI. Considering FDPI effects on the hippocampus, it was effective against the cholinergic dysfunction, AChE activity and content, and M1 receptor levels, which collectively could contribute to its anti-amnesic effect.

Ionizing radiation induces ferroptosis in granulocyte-macrophage hematopoietic progenitor cells of murine bone marrow

Purpose: To study whether radiation-induced bleeding in the bone marrow induced iron accumulation, and subsequently caused ferroptosis in granulocyte-macrophage hematopoietic progenitor cells.Materials and methods: Male mice were subjected to different doses (0, 4, 8, or 10 Gy) of gamma radiation from a ¹³⁷Cs source. The changes in iron metabolism or ferroptosis-related parameters of irradiated bone marrow were accessed with biochemical, histopathological, and antibody methods. Hematocytes were detected with a hematology analyzer. The counts of granulocyte-macrophage hematopoietic progenitor cells were measured with the granulocyte-macrophage colony-forming unit.Results: Iron accumulation occurred in the bone marrow, which caused by radiation-induced hemorrhage. The iron accumulation triggered an iron regulatory protein-ferroportin 1 axis to increase serum iron levels. Using LDN193189, radiation-induced iron accumulation was demonstrated to decrease white blood cell counts at least partly through a decrease in the counts of granulocyte-macrophage hematopoietic progenitor cells. The reduction in the counts of granulocyte-macrophage hematopoietic progenitor cells was subsequently demonstrated to attribute to ferroptosis with the use of ferroptosis inhibitors and through the detection of ferroptosis related-parameters. The survival rate of irradiated mice was improved using Ferrostatin-1 or LDN193189.Conclusions: These findings suggest that radiation-induced hemorrhage in the bone marrow causes ferroptosis in granulocyte-macrophage hematopoietic progenitor cells, and anti-ferroptosis has the potential to be a radioprotective strategy to ameliorate radiation-induced hematopoietic injury.

CLG from Hemp Seed Inhibits LPS-Stimulated Neuroinflammation in BV2 Microglia by Regulating NF-κB and Nrf-2 Pathways

The healthy benefits of hemp (Cannabis sativa L.) seed have often been attributed to its oils and proteins. Recent studies reveal that hemp seed phenylpropionamides could also show various bioactivities. Continuation of our study on hemp seed provided a phenylpropionamide, coumaroylaminobutanol glucopyranoside (CLG). This work investigated the neuroprotective effect of CLG and its underlying mechanism using lipopolysaccharide-induced BV2 microglia. Our study demonstrated that CLG increased adenosine monophosphate-activated protein kinase (AMPK) expression, suppressed the nuclear factor-kappa B (NF-κB) signaling pathway by inhibiting the phosphorylation of IκBα and NF-κB p65 and decreased proinflammatory cytokine levels in a concentration-dependent manner. Furthermore, CLG reduced the production of cellular reactive oxygen species and stimulated the nuclear factor erythroid 2-related factor 2 (Nrf-2) signaling pathway. Collectively, these results suggested that CLG effectively and simultaneously inhibited inflammatory responses and oxidative stress through the NF-κB and Nrf-2 signaling pathways. AMPK was also involved in the anti-inflammatory effect of CLG. This study provides new insights into the diverse bioactive constituents of hemp seed.

Kynurenic acid attenuates pro-inflammatory reactions in lipopolysaccharide-stimulated endothelial cells through the PPARδ/HO-1-dependent pathway

Kynurenic acid (KA) regulates energy homeostasis and alleviates inflammation in adipose tissue but how KA affects the atherosclerotic response in HUVECs remains unclear. We evaluated the effects of KA on lipopolysaccharide (LPS)-induced inflammation and apoptosis in HUVECs. KA enhanced peroxisome proliferator-activated receptor delta (PPARδ) expression in HUVECs and THP-1 cells and suppressed LPS-induced atherosclerotic responses through PPARδ-mediated signaling. Moreover, KA treatment mitigated LPS-induced phosphorylation of nuclear factor kappa B and pro-inflammatory cytokine release in HUVECs and THP-1 cells, and down-regulated adhesion molecules in HUVECs and adhesion of THP-1 cells to HUVECs following LPS treatment. KA treatment decreased LPS-induced inflammation and apoptosis, and also promoted heme oxygenase (HO)-1 expression, which suppresses inflammation in HUVECs. Suppression of PPARδ or HO-1 expression markedly mitigated the effects of KA on atherosclerotic responses in HUVECs. Thus, KA attenuates LPS-induced atherosclerotic responses by suppressing inflammation via the PPARδ/HO-1-dependent pathway.

Inhibitory Effects of a Novel Chrysin-Derivative, CPD 6, on Acute and Chronic Skin Inflammation

The skin is an important physiological barrier against external stimuli, such as ultraviolet radiation (UV), xenobiotics, and bacteria. Dermal inflammatory reactions are associated with various skin disorders, including chemical-induced irritation and atopic dermatitis. Modulation of skin inflammatory response is a therapeutic strategy for skin diseases. Here, we synthesized chrysin-derivatives and identified the most potent derivative of Compound 6 (CPD 6). We evaluated its anti-inflammatory effects in vitro cells of macrophages and keratinocytes, and in vivo dermatitis mouse models. In murine macrophages stimulated by lipopolysaccharide (LPS), CPD 6 significantly attenuated the release of inflammatory mediators such as nitric oxide (NO) (IC₅₀ for NO inhibition: 3.613 μM) and other cytokines. In cultured human keratinocytes, CPD 6 significantly attenuated the release of inflammatory cytokines induced by the combination of IFN-γ and TNF-α, UV irradiation, or chemical irritant stimulation. CPD 6 inhibited NFκB and JAK2/STAT1 signaling pathways, and activated Nrf2/HO-1 signaling. In vivo relevancy of anti-inflammatory effects of CPD 6 was observed in acute and chronic skin inflammation models in mice. CPD 6 showed significant anti-inflammatory properties both in vitro cells and in vivo dermatitis animal models, mediated by the inhibition of the NFκB and JAK2-STAT1 pathways and activation of Nrf2/HO-1 signaling. We propose that the novel chrysin-derivative CPD 6 may be a potential therapeutic agent for skin inflammation.

Oleocanthal Modulates LPS-Induced Murine Peritoneal Macrophages Activation via Regulation of Inflammasome, Nrf-2/HO-1, and MAPKs Signaling Pathways

The present study was designed to investigate the role of the canonical and noncanonical inflammasome, MAPKs and NRF-2/HO-1, signaling pathways involved in the antioxidant and anti-inflammatory activities of oleocanthal in lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages. Isolated cells were treated with oleocanthal in the presence or absence of LPS (5 μg mL^-1) for 18 h. Oleocanthal showed a potent reduction of reactive oxygen species (ROS) (25 μM, 50. 612 ± 0.02; 50 μM, 53. 665 ± 0.09; 100 μM, 52. 839 ± 0.02), nitrites (25 μM, 0.631 ± 0.07; 50 μM, 0.652 ± 0.07; 100 μM, 0.711 ± 0.08), and pro-inflammatory cytokines levels when compared with LPS-DMSO-treated control cells. In terms of enzymes protein expression, oleocanthal was able to downregulate iNOS (25 μM, 0.173 ± 0.02; 50 μM, 0.149 ± 0.01; 100 μM, 0.150 ± 0.01; p < 0.001), COX-2 (25 μM, 0.482 ± 0.08; 50 μM, 0.469 ± 0.05; 100 μM, 0.418 ± 0.06; p < 0.001), and mPGES-1 (25 μM, 0.185 ± 0.11; 50 μM, 0.218 ± 0.13; 100 μM, 0.161 ± 0.15; p < 0.001) as well as p38 (25 μM, 0.366 ± 0.11; 50 μM, 0.403 ± 0.13; 100 μM, 0.362 ± 0.15; p < 0.001), JNK (25 μM, 0.443 ± 0.11; 50 μM, 0.514 ± 0.13; 100 μM, 0.372 ± 0.15; p < 0.001), and ERK (25 μM, 0.294 ± 0.01; 50 μM, 0.323 ± 0.01; 100 μM, 0.274 ± 0.01; p < 0.001) protein phosphorylation, which was accompanied by an upregulation of Nrf-2 (25 μM, 1.57 ± 0.01; 50 μM, 1.54 ± 0.01; 100 μM, 1.63 ± 0.05; p < 0.05) and HO-1(25 μM, 2.12 ± 0,03; 50 μM, 2.24 ± 0.01; 100 μM, 1.92 ± 0.05; p < 0.01) expression in comparison with LPS-DMSO cells. Moreover, oleocanthal inhibited canonical and noncanonical inflammasome signaling pathways. Thus, oleocanthal might be a promising natural agent for future treatment of immune-inflammatory diseases.

Cancer: Thymoquinone antioxidant/pro-oxidant effect as potential anticancer remedy

Recently, there is growing interest in the natural bioactive components having anticancer activity. Thymoquinone (TQ), the principle active constituent of black seed (Nigella sativa), has promising properties including anticancer and chemosensitizing peculiarities. The anticancer power of TQ is accomplished by several aspects; including promotion of apoptosis, arrest of cell cycle and ROS generation. In addition, it boosts the immune system and lessens the side effects associated with traditional anticancer therapy. TQ also controls angiogenesis and cancer metastasis. This review focuses on the potential aspects and mechanisms by which TQ acquires its actions.

Gas Signaling Molecules and Mitochondrial Potassium Channels

Recently, gaseous signaling molecules, such as carbon monoxide (CO), nitric oxide (NO), and hydrogen sulfide (H₂S), which were previously considered to be highly toxic, have been of increasing interest due to their beneficial effects at low concentrations. These so-called gasotransmitters affect many cellular processes, such as apoptosis, proliferation, cytoprotection, oxygen sensing, ATP synthesis, and cellular respiration. It is thought that mitochondria, specifically their respiratory complexes, constitute an important target for these gases. On the other hand, increasing evidence of a cytoprotective role for mitochondrial potassium channels provides motivation for the analysis of the role of gasotransmitters in the regulation of channel function. A number of potassium channels have been shown to exhibit activity within the inner mitochondrial membrane, including ATP-sensitive potassium channels, Ca²⁺-activated potassium channels, voltage-gated Kv potassium channels, and TWIK-related acid-sensitive K⁺ channel 3 (TASK-3). The effects of these channels include the regulation of mitochondrial respiration and membrane potential. Additionally, they may modulate the synthesis of reactive oxygen species within mitochondria. The opening of mitochondrial potassium channels is believed to induce cytoprotection, while channel inhibition may facilitate cell death. The molecular mechanisms underlying the action of gasotransmitters are complex. In this review, we focus on the molecular mechanisms underlying the action of H₂S, NO, and CO on potassium channels present within mitochondria.

Activation of Nrf2/HO-1 Pathway by Nardochinoid C Inhibits Inflammation and Oxidative Stress in Lipopolysaccharide-Stimulated Macrophages

The roots and rhizomes of Nardostachys chinensis have neuroprotection and cardiovascular protection effects. However, the specific mechanism of N. chinensis is not yet clear. Nardochinoid C (DC) is a new compound with new skeleton isolated from N. chinensis and this study for the first time explored the anti-inflammatory and anti-oxidant effect of DC. The results showed that DC significantly reduced the release of nitric oxide (NO) and prostaglandin E₂ (PGE₂) in lipopolysaccharide (LPS)-activated RAW264.7 cells. The expression of pro-inflammatory proteins including inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were also obviously inhibited by DC in LPS-activated RAW264.7 cells. Besides, the production of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were also remarkably inhibited by DC in LPS-activated RAW264.7 cells. DC also suppressed inflammation indicators including COX-2, PGE₂, TNF-α, and IL-6 in LPS-stimulated THP-1 macrophages. Furthermore, DC inhibited the macrophage M1 phenotype and the production of reactive oxygen species (ROS) in LPS-activated RAW264.7 cells. Mechanism studies showed that DC mainly activated nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, increased the level of anti-oxidant protein heme oxygenase-1 (HO-1) and thus produced the anti-inflammatory and anti-oxidant effects, which were abolished by Nrf2 siRNA and HO-1 inhibitor. These findings suggested that DC could be a new Nrf2 activator for the treatment and prevention of diseases related to inflammation and oxidative stress.

Melaleuca alternifolia Induces Heme Oxygenase-1 Expression in Murine RAW264.7 Cells through Activation of the Nrf2-ARE Pathway

Melaleuca alternifolia concentrate (MAC) is the refined essential oil of the Australian native plant Melaleuca alternifolia. MAC has been reported to suppress the production of pro-inflammatory cytokines in both murine RAW264.7 macrophages and human monocytes stimulated with lipopolysaccharide (LPS). However, the mechanisms involved in this effect remain unclear. This study aims to delineate the molecular mechanisms that drive the anti-inflammatory activity of MAC and its active component, terpinen-4-ol, in macrophages. The effects of MAC on RAW264.7 cells were studied using western blotting, real-time PCR, an electrophoretic mobility shift assay (EMSA), and NF-[Formula: see text]B luciferase reporter assays. Our results showed that MAC significantly increased both the mRNA and protein levels of heme oxygenase-1 (HO-1) via p38 and JNK MAPK activation. In addition, we showed that MAC significantly increased the activation and nuclear translocation of NF-E2-related factor 2 (Nrf2), a key transcription factor regulating HO-1 induction. MAC was also associated with significant inhibition of iNOS expression, NO production, and NF-[Formula: see text]B activation. HO-1 was required for these anti-inflammatory effects as tin protoporphyrin IX (SnPPIX), an HO-1 inhibitor, abolished the effects of MAC on LPS-induced iNOS, NO, and NF-[Formula: see text]B activation. Our results indicate that MAC induces HO-1 expression in murine macrophages via the p38 MAPK and JNK pathways and that this induction is required for its anti-inflammatory activity.

Synthesis and biological activity of new phthalimides as potential anti-inflammatory agents

The overproduction of nitric oxide (NO) plays an important role in a variety of pathophysiological processes, including inflammation. Therefore, the suppression of NO production is a promising target in the design of anti-inflammatory agents. In the present study, a series of phthalimide analogs was synthesized, and their anti-inflammatory activities were evaluated using lipopolysaccharide (LPS)-stimulated NO production in cultured murine macrophage RAW264.7 cells. A structure-activity relationship study showed that the free hydroxyl group at C-4 and C-6 and the bulkiness of the N-substituted alkyl chain are associated with biological activity. Among the series of phthalimide derivatives, compound IIh exhibited potent inhibitory activity, with an IC₅₀ value of 8.7µg/mL. Further study revealed that the inhibitory activity of compound IIh was correlated with the down-regulation of the mRNA and protein expression of LPS-stimulated inducible nitric oxide synthase (iNOS). Compound IIh also suppressed the induction of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1β in LPS-stimulated RAW 264.7 cells. The anti-inflammatory activity of compound IIh was also found to be associated with the suppression of the Toll-like receptor (TLR)4 signaling pathway by down-regulating the activation of interferon regulatory factor 3 (IRF-3) and interferon-β and signal transducer expression. These findings demonstrate that novel phthalimides might be potential candidates for the development of anti-inflammatory agents.

Isocyperol, isolated from the rhizomes of Cyperus rotundus, inhibits LPS-induced inflammatory responses via suppression of the NF-κB and STAT3 pathways and ROS stress in LPS-stimulated RAW 264.7 cells

The rhizomes of Cyperus rotundus (cyperaceae) have been used in Korean traditional medicines for treating diverse inflammatory diseases. However, little is known about the biological activities of isocyperol, a sesquiterpene isolated from C. rotundus, and their associated molecular mechanisms. In this study, we found that isocyperol significantly inhibited lipopolysaccharide (LPS)-induced production of nitrite oxide (NO) and prostaglandin E2 (PGE2) and suppressed LPS-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the mRNA and protein levels in RAW 264.7 macrophages. In addition, isocyperol downregulated the LPS-induced expression of several proinflammatory cytokines, such as interleukin-1beta (IL-1β), IL-6, and monocyte chemotactic protein-1 (MCP-1). Isocyperol treatment suppressed the LPS-induced nuclear translocation and transcriptional activation of nuclear factor-kappaB (NF-κB) in macrophages. Moreover, the activation of STAT3, another proinflammatory signal, was suppressed by isocyperol in LPS-stimulated RAW 264.7 cells. Isocyperol pretreatment also induced heme oxygenase-1 (HO-1) expression and reduced LPS-stimulated reactive oxygen species (ROS) accumulation in macrophages. Furthermore, isocyperol significantly increased the survival rate and attenuated serum levels of NO, PGE2, and IL-6 in LPS-induced septic shock mouse model. Taken together, these data indicate that isocyperol suppress septic shock through negative regulation of pro-inflammatory factors through inhibition of the NF-κB and STAT3 pathways and ROS. To our knowledge, this is the first report on the biological activity of isocyperol and its molecular mechanism of action.

Selenium Deficiency Affects the mRNA Expression of Inflammatory Factors and Selenoprotein Genes in the Kidneys of Broiler Chicks

The aim of this study was to investigate the influence of Se deficiency on the transcription of inflammatory factors and selenoprotein genes in the kidneys of broiler chicks. One hundred fifty 1-day-old broiler chicks were randomly assigned to two groups fed with either a low-Se diet (L group, 0.033 mg/kg Se) or an adequate Se diet (C group, 0.2 mg/kg Se). The levels of uric acid (UA) and creatinine (Cr) in the serum and the mRNA levels of 6 inflammatory factors and 25 selenoprotein genes in the kidneys were measured as the clinical signs of Se deficiency occurred at 20 days old. The results indicated that the contents of UA and Cr in the serum increased in L group (p < 0.05), and the mRNA levels of the inflammatory factors (NF-κB, iNOS, COX-2, and TNF-α) increased in L group (p < 0.05). Meanwhile, the mRNA levels of PTGEs and HO-1 were not changed. In addition, 25 selenoprotein transcripts displayed ubiquitous expression in the kidneys of the chicks. The mRNA levels of 14 selenoprotein genes (Dio1, Dio2, GPx3, Sepp1, SelH, SelI, SelK, Sepn1, SelO, SelW, Sep15, SelT, SelU, and SelS) decreased, and 9 selenoprotein genes (GPx1, GPx2, GPx4, SelPb, Txnrd1, Txnrd2, Txnrd3, SPS2, and SelM) increased in L group (p < 0.05), but the Dio3 and Sepx1 mRNA levels did not change. The results indicated that Se deficiency resulted in kidney dysfunction, activation of the NF-κB pathway, and a change in selenoprotein gene expression. The changes of inflammatory factor and selenoprotein gene expression levels were directly related to the abnormal renal functions induced by Se deficiency.

A comparison of statistical approaches used for the optimization of soluble protein expression in Escherichia coli

During a discovery project of potential inhibitors for three proteins, TNF-α, RANKL and HO-1, implicated in the pathogenesis of rheumatoid arthritis, significant amounts of purified proteins were required. The application of statistically designed experiments for screening and optimization of induction conditions allows rapid identification of the important factors and interactions between them. We have previously used response surface methodology (RSM) for the optimization of soluble expression of TNF-α and RANKL. In this work, we initially applied RSM for the optimization of recombinant HO-1 and a 91% increase of protein production was achieved. Subsequently, we slightly modified a published incomplete factorial approach (called IF1) in order to evaluate the effect of three expression variables (bacterial strains, induction temperatures and culture media) on soluble expression levels of the three tested proteins. However, soluble expression yields of TNF-α and RANKL obtained by the IF1 method were significantly lower (<50%) than those obtained by RSM. We further modified the IF1 approach by replacing the culture media with induction times and the resulted method called IF-STT (Incomplete Factorial-Stain/Temperature/Time) was validated using the three proteins. Interestingly, soluble expression levels of the three proteins obtained by IF-STT were only 1.2-fold lower than those obtained by RSM. Although RSM is probably the best approach for optimization of biological processes, the IF-STT is faster, it examines the most important factors (bacterial strain, temperature and time) influencing protein soluble expression in a single experiment, and can be used in any recombinant protein expression project as a starting point.

Spiranthes sinensis Suppresses Production of Pro-Inflammatory Mediators by Down-Regulating the NF-κB Signaling Pathway and Up-Regulating HO-1/Nrf2 Anti-Oxidant Protein

Spiranthes sinensis is an east Asian wild orchid used in Chinese folk medicine. In this study, an ethyl acetate fraction from S. sinensis(SSE) was found to suppress the production of LPS-stimulated inflammatory mediators in RAW264.7 cells and BALB/c mice. SSE inhibited the production of pro-inflammatory mediators such as nitric oxide (NO), prostaglandin E2 (PGE2), tumo necrosis factor-α (TNF-α), IL-1β, and IL-6 in LPS-stimulated RAW264.7 cells. SSE also significantly suppressed LPS-stimulated protein levels of iNOS and mPGES-1 by blocking IκB phosphorylation, NF-κB nuclear translocation, and MAPKs phosphorylation. In addition, SSE treatment also enhanced protein levels of HO-1 and anti-oxidant enzymes (SOD-1, CAT, and GPx-1) through the nuclear translocation of Nrf2 in LPS-stimulated RAW264.7 cells. In vivo, we demonstrated that SSE attenuated the levels of pro-inflammatory mediators (NO, TNF-α, IL-1β, and IL-6), ALT, and AST in the serum of LPS-stimulated BALB/c mice. Western blotting revealed that SSE enhanced HO-1 expression in lung and liver tissue after LPS injection in mice. These results suggest that the anti-inflammatory properties of SSE involve the suppression of iNOS, mPGES-1, and inflammatory mediators by inducing the HO-1 pathway in LPS-stimulated RAW264.7 cells and BALB/c mice.

Inhibitory Effects of Epimedium Herb on the Inflammatory Response In Vitro and In Vivo

Epimedium Herb (EH) is a medicinal herb used in traditional Eastern Asia. In this study described, we investigated the biological effects of Epimedium Herb water extract (EHWE) on lipopolysaccharide (LPS)-mediated inflammation in macrophages and local inflammation in vivo. We also investigated the biological effects of EHWE on the production of inflammatory mediators, pro-inflammatory cytokines and related products, as well as nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) activation in LPS-stimulated macrophages. The analgesic effect of the acetic acid-induced writhing response and inhibitory activity on xylene-induced ear edema was also evaluated in mice. EHWE exhibited anti-inflammatory effects by inhibiting the production of nitric oxide (NO), interleukin (IL)-6 and IL-1β. In addition, EHWE strongly suppressed inducible nitric oxide synthase (iNOS), a NO synthesis enzyme, induced heme oxygenase-1 (HO-1) expression, and inhibited NF-κB activation as well as MAPK pathway phosphorylation. Furthermore, EHWE exhibited an analgesic effect on the writhing response and an inhibitory effect on ear edema in mice. For the first time, we demonstrated the anti-inflammatory effects and inhibitory mechanism in macrophages, as well as the inhibitory activity of EHWE in vivo. Our results indicate a potential use of EHWE as an inflammatory therapeutic agent developed from a natural substance.