Azilsartan Suppressed LPS-Induced Inflammation in U937 Macrophages through Suppressing Oxidative Stress and Inhibiting the TLR2/MyD88 Signal Pathway

Inflammatory Response of THP1 and U937 Cells: The RNAseq Approach

THP1 and U937 are monocytic cell lines that are common bioassays to reflect monocyte and macrophage activities in inflammation research. However, THP-1 is a human monocytic leukemia cell line, and U937 originates from pleural effusion of histiocytic lymphoma; thus, even though they serve as bioassay in inflammation research, their response to agonists is not identical. Consequently, there has yet to be a consensus about the panel of strongly regulated genes in THP1 and U937 cells representing the inflammatory response to LPS and IFNG. Therefore, we have performed an RNAseq of THP1 and U937 exposed to LPS and IFNG to identify the most sensitive genes and the unique properties of each individual cell line. When applying a highly stringent threshold, we could identify 43, 8 up and 94, 103 down-regulated genes in THP1 and U937 cells, respectively. In THP1 cells, among the most strongly up-regulated genes are CCL1, CXCL2, CXCL3, IL1A, IL1B, IL6, and PTGES. In U937 cells, the strongest up-regulated genes include CSF2, CSF3, CXCL2, CXCL5, CXCL6, IL1A, IL19, IL36G, IL6, ITGA1, ITGA2, and PTGS2. Even though THP1 is considerably less responsive than U937, there are genes commonly upregulated by LPS and IFNG, including the CCL1, CCL3, CCL20, CXCL2, CXCL3, CXCL8, as well as IL1A, IL1B, IL23A, IL6, and genes of prostaglandin synthesis PTGES and PTGS2. Downregulated genes are limited to NRGN and CD36. This head-to-head comparison revealed that THP1 is less responsive than U937 cells to LPS and IFNG and identified a panel of highly regulated genes that can be applied in bioassays in inflammation research. Our data further propose bulk RNAseq as a standard method in bioassay research.

Alkaloids from Piper longum L and their Anti-inflammatory Properties

Piper longum L. (PL) is considered one of the most important species traditionally used for treating various ailments and has indicated the presence of alkaloids, flavonoids, and steroids. In this study, we isolated the chemical compounds of PL leaves, and measured NO, IL-6, iNOS, as well as COX-2 protein levels. In addition, molecular docking analysis was used to further understand the anti-inflammation effect of the compounds. We identified one new alkaloid named piperlongumine A (1) with ten known compounds (2-11). The new compound (1) and two other alkaloids 2E)-3-(4-hydroxy-3-methoxyphenyl)-1-(pyrrol-1-yl) propanone (7) and piperchabamide A (8) significantly reduced NO production in LPS-stimulated RAW 264.7 cells with the IC50 values of 0.97±0.05 μM, 0.91±0.07 μM, 1.63±0.14 μM, respectively. Moreover, at concentration of 2 μM, compound 1 inhibited approximately 98±0.64 % of IL-6 secretion, and decreased iNOS and COX-2 protein level by about 96 and 19 folds compared to LPS treatment alone, respectively. Furthermore, compounds 1, 7, and 8 were predicted to bind and inhibit IL-6, TNF-α, and iNOS, with compound 1 showing the highest binding energy of -7.09 kcal/mol. This study provides new insights for potential anti-inflammatory drug design and warrants further investigation.

Multifunctional polymeric nanofibrous scaffolds enriched with azilsartan medoxomil for enhanced wound healing

A prolonged and compromised wound healing process poses a significant clinical challenge, necessitating innovative solutions. This research investigates the potential application of nanotechnology-based formulations, specifically nanofiber (NF) scaffolds, in addressing this issue. The study focuses on the development and characterization of multifunctional nanofibrous scaffolds (AZL-CS/PVA-NF) composed of azilsartan medoxomil (AZL) enriched chitosan/polyvinyl alcohol (CS/PVA) through electrospinning. The scaffolds underwent comprehensive characterization both in vitro and in vivo. The mean diameter and tensile strength of AZL-CS/PVA-NF were determined to be 240.42 ± 3.55 nm and 18.05 ± 1.18 MPa, respectively. A notable drug release rate of 93.86 ± 2.04%, was observed from AZL-CS/PVA-NF over 48 h at pH 7.4. Moreover, AZL-CS/PVA-NF exhibited potent antimicrobial efficacy for Staphylococcus aureus and Pseudomonas aeruginosa. The expression levels of Akt and CD31 were significantly elevated, while Stat3 showed a decrease, indicating a heightened tissue regeneration rate with AZL-CS/PVA-NF compared to other treatment groups. In vivo ELISA findings revealed reduced inflammatory markers (IL-6, IL-1β, TNF-α) within treated skin tissue, implying a beneficial effect on injury repair. The comprehensive findings of the present endeavour underscore the superior wound healing activity of the developed AZL-CS/PVA-NF scaffolds in a Wistar rat full-thickness excision wound model. This indicates their potential as novel carriers for drugs and dressings in the field of wound care.

The preventive effects of Saccharomyces boulardii against oxidative stress induced by lipopolysaccharide in rat brain

The brain is sensitive to oxidative stress, which can trigger microglial activation and neuroinflammation. Antioxidant therapies may provide neuroprotection against oxidative stress. In recent years antioxidant effects of probiotics and their possible mechanisms in oxidative stress-related models have been determined. In the current study, for the first time, we assessed the effects of Saccharomyces boulardii on oxidative stress provoked by lipopolysaccharide (LPS) in the rat brain. Four groups of animals were used, including the control, LPS, S. boulardii + LPS, and S. boulardii groups. All animals received either saline or S. boulardii (1010 CFU) by gavage for four weeks. Between days 14 and 22, all animals received either LPS (250 μg/kg) or saline by intraperitoneal (i.p.) injection. S. boulardii was able to inhibit lipid peroxidation and prevent the reduction of antioxidant levels, including glutathione and catalase in the model of oxidative stress induced by LPS in the rat hippocampus and cortex. Also, it increased the lowered ratio of glutathione/oxidized glutathione in both tissues. Serum levels of anti-inflammatory interleukin 10 (IL-10) and proinflammatory cytokines IL-6 and IL-8 increased and decreased, respectively. S. boulardii has potential antioxidant activities in oxidative stress-related model, possibly modulating gut microbiota, immune defense, and antioxidant enzyme activities that can be considered in preventing oxidative stress-related central nervous system (CNS) diseases.

Exosomes from SHED-MSC regulate polarization and stress oxidative indexes in THP-1 derived M1 macrophages

OBJECTIVE

The inhibition of M1 macrophages may be interesting for targeted therapy with mesenchymal stem cell-derived Exosomes (MSC-EXOs). This study aimed to investigate the stem cells of human exfoliated deciduous teeth-derived EXOs (SHED-MSC-EXOs) effect on regulating the pro- and anti-oxidant indexes and inhibiting M1 macrophage polarization. Besides, an in-silico analysis of SHED-MSC-EXO miRNAs as the highest frequency of small RNAs in the exosomes was performed to discover the possible mechanism.

METHODS

The flow cytometry analysis of CD80 and CD86 as M1-specific markers confirmed the polarization of macrophages derived from THP-1 cells. After exosome isolation, characterization, and internalization, THP-1-derived M1 macrophages were treated with SHED-MSC-EXOs. M1-specific markers and pro- and anti-oxidant indexes were evaluated. For in-silico analysis of SHED-MSC-EXOs miRNAs, initial miRNA array data of SHED-EXOs is collected from GEO, and the interaction of the miRNAs in M1 macrophage polarization (M1P), mitochondrial oxidative stress (MOS) and LPS-induced oxidative stress (LOS) were analyzed by miRWalk 3.0 server. Outcomes were filtered by 75th percentile signal intensity, score cut-off ≥0.95, minimum free energy (MEF)≤ -20 kcal/mol, and seed = 1.

RESULTS

It shows a decrease in the expression of CD80 and CD81, a reduction in pro-oxidant indicators, and an increase in the anti-oxidant indexes (P < 0.05). Computational analysis showed that eight microRNAs of SHED-MSC-EXO miRNAs can bind to and interfere with the expression of candidate genes in the M1P, MOS, and LOS pathways simultaneously.

CONCLUSION

SHED-MSCs-EXOs can be utilized to treat conditions related to M1 macrophage-induced diseases (M1IDs) due to their unique physical properties and ability to penetrate target cells easily.

Azilsartan improves urinary albumin excretion in hypertension mice

Hypertension is one of the most important risk factors for chronic kidney diseases, leading to hypertensive nephrosclerosis, including excessive albuminuria. Azilsartan, an angiotensin II type 1 receptor blocker, has been widely used for the treatment of hypertension. However, the effects of Azilsartan on urinary albumin excretion in hypertension haven't been reported before. In this study, we investigated whether Azilsartan possesses a beneficial property against albuminuria in mice treated with angiotensin II and a high-salt diet (ANG/HS). Compared to the control group, the ANG/HS group had higher blood pressure, oxidative stress, and inflammatory response, all of which were rescued by Azilsartan dose-dependently. Importantly, the ANG/HS-induced increase in urinary albumin excretion and decrease in the expression of occludin were reversed by Azilsartan. Additionally, it was shown that increased fluorescence intensity of FITC-dextran, declined trans-endothelial electrical resistance (TEER) values, and reduction of occludin and krüppel-like factor 2 (KLF2) were observed in ANG/HS-treated human renal glomerular endothelial cells (HrGECs), then prevented by Azilsartan. Moreover, the regulatory effect of Azilsartan on endothelial monolayer permeability in ANG/HS-treated HrGECs was abolished by the knockdown of KLF2, indicating KLF2 is required for the effect of Azilsartan. We concluded that Azilsartan alleviated diabetic nephropathy-induced increase in Uterine artery embolization (UAE) mediated by the KLF2/occludin axis.

Development and Validation of a Fluorogenic Probe for Lysosomal Zinc Release

Zinc homeostasis, which allows optimal zinc utilization in diverse life processes, is responsible for the general well-being of human beings. This paper describes developing and validating an easily accessible indole-containing zinc-specific probe in the cellular milieu. The probe was synthesized from readily available starting materials and was subjected to steady-state fluorescence studies. It showed selective sensing behavior towards Zn2+ with reversible binding. The suppression of PET (Photoinduced Electron Transfer) and ESIPT (Excited State Intramolecular Proton Transfer) elicited selectivity, and the detection limit was 0.63 μM (LOQ 6.8 μM). The zinc sensing capability of the probe was also screened in the presence of low molecular weight ligands [LMWLs] and showed interference only with GSH and ATP. It is non-toxic and can detect zinc in different cell lines under various stress conditions such as inflammation, hyperglycemia, and apoptosis. The probe could stain the early and late stages of apoptosis in PAN-2 cells by monitoring the zinc release. Most experiments were conducted without external zinc supplementation, showing its innate ability to detect zinc.

Phloroglucinol possesses anti-inflammatory activities by regulating AMPK/Nrf2/HO-1 signaling pathway in LPS-stimulated RAW264.7 murine macrophages

BACKGROUND

Inflammation is closely related to the pathogenesis of chronic illnesses. Secondary metabolites of marine seaweeds are recognized as reliable sources of bioactive compounds due to their health benefits besides their nutritional value. The objective of this study was to determine the potential anti-inflammatory effect of phloroglucinol (Phl) in RAW264.7 murine macrophages after lipopolysaccharides (LPS) stimulation.

METHODS

MTT, nitric oxide (NO), and DCFH-DA assays were conducted to determine cell viability, NO production, and reactive oxygen species (ROS) generation respectively. Pro-inflammatory cytokines and prostaglandin E2 (PGE2) levels were measured using ELISA assay kits. Protein expression levels were determined by western blot analysis.

RESULTS

Phl treatment showed a promising anti-inflammatory effect by reducing NO production, secretion of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), PGE2 production, protein expression levels of inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), and ROS generation in LPS-stimulated RAW264.7 murine macrophages. Phl treatment upregulated heme oxygenase-1 (HO-1) expression by inducing nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and activating AMPK. However, Zinc protoporphyrin (ZnPP), an inhibitor of HO-1, partially reversed these effects, including NO production, pro-inflammatory cytokine secretion, iNOS, COX-2 and HO-1 expression, and ROS generation.

CONCLUSION

Phl has potential anti-inflammatory activities by regulating AMPK/Nrf2/HO-1 pathway in LPS-stimulated RAW264.7 murine macrophages.

Azilsartan inhibits inflammation-triggered bone resorption and osteoclastogenesis in vivo via suppression of TNF-α expression in macrophages

Introduction

Hypertension is a major risk factor for cardiovascular disease (CVD) and is associated with increased bone loss due to excessive activity of the local renin-angiotensin system (RAS). Angiotensinogen/Angiotensin (ANG) II/Angiotensin II type 1 receptor (AT1R) axis is considered as the core axis regulating RAS activity. Azilsartan is an FDA-approved selective AT1R antagonist that is used to treat hypertension. This study aimed to determine whether azilsartan affects formation of osteoclast, resorption of bone, and the expression of cytokines linked with osteoclastogenesis during lipopolysaccharide (LPS)-triggered inflammation in vivo.

Methods

In vivo, following a 5-day supracalvarial injection of LPS or tumor necrosis factor-alpha (TNF-α) with or without azilsartan, the proportion of bone resorption and the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells, which are identified as osteoclasts on mice calvariae were counted. The mRNA expression levels of TRAP, cathepsin K, receptor activator of NF-κB ligand (RANKL), and TNF-α were also evaluated. In vitro, the effect of azilsartan (0, 0.01, 0.1, 1, and 10 μM) on RANKL and TNF-α-triggered osteoclastogenesis were investigated. Also, whether azilsartan restrains LPS-triggered TNF-α mRNA and protein expression in macrophages and RANKL expression in osteoblasts were assessed. Furthermore, western blotting for analysis of mitogen-activated protein kinases (MAPKs) signaling was conducted.

Results

Azilsartan-treated calvariae exhibited significantly lower bone resorption and osteoclastogenesis than those treated with LPS alone. In vivo, LPS with azilsartan administration resulted in lower levels of receptor activator of RANKL and TNF-α mRNA expression than LPS administration alone. Nevertheless, azilsartan did not show inhibitory effect on RANKL- and TNF-α-triggered osteoclastogenesis in vitro. Compared to macrophages treated with LPS, TNF-α mRNA and protein levels were lower in macrophages treated by LPS with azilsartan. In contrast, RANKL mRNA and protein expression levels in osteoblasts were the same in cells co-treated with azilsartan and LPS and those exposed to LPS only. Furthermore, azilsartan suppressed LPS-triggered MAPKs signaling pathway in macrophages. After 5-day supracalvarial injection, there is no difference between TNF-α injection group and TNF-α with azilsartan injection group.

Conclusion

These findings imply that azilsartan prevents LPS-triggered TNF-α production in macrophages, which in turn prevents LPS-Triggered osteoclast formation and bone resorption in vivo.

Nephroprotective effect of AT-MSCs against cisplatin-induced EMT is improved by azilsartan via attenuating oxidative stress and TGF-β/Smad signaling

The nephrotoxicity of cisplatin (CIS) is a significant complication that challenges its clinical applicability. The epithelial to mesenchymal transition (EMT) may be included in the pathogenesis of CIS-evoked nephrotoxicity. Therefore, the current study aimed to evaluate, for the first time, the possible protective effect of AZL and/or AT-MSCs against CIS-induced EMT in rats on molecular bases. Fifty-four healthy Wistar male albino rats were used in this study. Different biochemical markers of kidney function as well as oxidative stress parameters were investigated. Additionally, renal histopathological study was performed. The expression of EMT-related proteins and genes was evaluated by western blotting and qRT-PCR. CIS markedly increased SCr, BUN, uric acid and renal MDA levels, with concomitant decrease in serum total protein, renal GSH level and SOD activity. Furthermore, it suppressed the expression of Cdh1 gene, increased the α-SMA, Acta2, Cdh2 and Vim genes expression, down regulated the expression of E-cad protein and up-regulated the α-SMA, TGF-β1, p-Smad2/3 and Snail proteins expression. Kidney tissues showed severe histopathological alterations and extensive collagen accumulation. Conversely, the treatment with either AZL or AT-MSCs significantly attenuated these alterations caused by CIS. Interestingly, the combined therapy of AZL and AT-MSCs has a superior ameliorative effect than AT-MSCs alone. In conclusion, this study, for the first time, revealed that AZL and/ or AT-MSCs successfully ameliorated the CIS-induced EMT via the inhibition of oxidative stress and TGF-β/Smad signaling pathway. Intriguingly, AZL enhanced the effect of AT-MSCs making them promising agents for kidney protection against CIS-induced EMT.

Azilsartan Modulates HMGB1/NF-κB/p38/ERK1/2/JNK and Apoptosis Pathways during Renal Ischemia Reperfusion Injury

Renal ischemia/reperfusion (IR) injury is characterized by an unexpected impairment of blood flow to the kidney. Azilsartan is an angiotensin receptor blocker that is approved for the management of hypertension. The present study aimed to investigate, on molecular basics, the nephroprotective activity of azilsartan on renal IR injury in rats. Rats were assigned into four groups: (1) Sham group, (2) Azilsartan group, (3) IR group, and (4) IR/Azilsartan-treated group. Histological examination and renal function were evaluated. Levels of KIM-1, HMGB1, caspase 3, GPX, SOD, NF-κB, and p53 proteins were investigated using ELISA. mRNA levels of IL-1β, IL6, IL10, TNF-α, NF-κB, p53, and bax were assessed by qRT-PCR. Expression of p38, JNK, and ERK1/2 proteins was investigated by Western blotting. IR injury resulted in tissue damage, elevation of creatinine, BUN, KIM-1, HMGB1, caspase 3, NF-κB, and p53 levels, decreasing GPX and SOD activities, and up-regulation of NF-κB, IL-1β, IL6, TNF-α, p53, and bax genes. Furthermore, it up-regulated the expression of phosphorylated/total ratio of p38, ERK1/2, and JNK proteins. Interestingly, treatment of the injured rats with azilsartan significantly alleviated IR injury-induced histopathological and biochemical changes. It reduced the creatinine, BUN, KIM-1, HMGB1, caspase-3, NF-κB, and p53 levels, elevated GPX and SOD activities, down-regulated the expression of NF-κB, IL-1β, IL6, TNF-α, p53, and bax genes, and up-regulated IL10 gene expression. Furthermore, it decreased the phosphorylated/total ratio of p38, ERK1/2, and JNK proteins. Azilsartan exhibited nephroprotective activity in IR-injured rats via its antioxidant effect, suppression of inflammation, attenuation of apoptosis, and inhibition of HMGB1/NF-κB/p38/ERK1/2/JNK signaling pathway.

Indirect effect of alpha-1-antitrypsin on endotoxin-induced IL-1β secretion from human PBMCs

Human alpha-1-antitrypsin (AAT) encoded by the SERPINA1 gene, is an acute phase glycoprotein that regulates inflammatory responses via both protease inhibitory and non-inhibitory activities. We previously reported that AAT controls ATP-induced IL-1β release from human mononuclear cells by stimulating the release of small bioactive molecules. In the current study, we aimed to elucidate the identity of these putative effectors released from human PBMCs in response to AAT, which may inhibit the LPS-induced release of IL-1β. We pre-incubated human PBMCs alone or with different preparations of AAT (4 mg/ml) for 30 min at 37°C, 5% CO₂, and collected cell supernatants filtered through centrifugal filters (cutoff 3 kDa) to eliminate AAT and other high molecular weight substances. Supernatants passed through the filters were used to culture PBMCs isolated from the autologous or a heterologous donors with or without adding LPS (1 μg/ml) for 6 h. Unexpectedly, supernatants from PBMCs pre-incubated with AAT (Zemaira^®), but not with other AAT preparations tested or with oxidized AAT (Zemaira^®), lowered the LPS-induced release of IL-1β by about 25%–60% without affecting IL1B mRNA. The reversed-phase liquid chromatography coupled with mass spectrometry did not confirm the hypothesis that small pro-resolving lipid mediators released from PBMCs after exposure to AAT (Zemaira^®) are responsible for lowering the LPS-induced IL-1β release. Distinctively from other AAT preparations, AAT (Zemaira^®) and supernatants from PBMCs pre-treated with this protein contained high levels of total thiols. In line, mass spectrometry analysis revealed that AAT (Zemaira^®) protein contains freer Cys232 than AAT (Prolastin^®). Our data show that a free Cys232 in AAT is required for controlling LPS-induced IL-1β release from human PBMCs. Further studies characterizing AAT preparations used to treat patients with inherited AAT deficiency remains of clinical importance.

Sophorolipid Suppresses LPS-Induced Inflammation in RAW264.7 Cells through the NF-κB Signaling Pathway

Objectives: Biosurfactants with anti-inflammatory activity may alleviate skin irritation caused by synthetic surfactants in cleaning products. Sophorolipid (SL) is a promising alternative to synthetic surfactants. However, there are few reports on the anti-inflammatory activity of SL and the underlying mechanism. The purpose of this work is to verify that lipopolysaccharide (LPS)-induced inflammation could be inhibited through targeting the pathway of nuclear factor-κB (NF-κB) in RAW264.7 cells. Methods: The influence of SL on cytokine release was investigated by LPS-induced RAW264.7 cells using ELISA. The quantification of the protein expression of corresponding molecular markers was realized by Western blot analysis. Flow cytometry was employed to determine the levels of Ca²⁺ and reactive oxygen species (ROS). The relative expression of inducible nitric oxide synthase (INOS) and cyclooxygenase-2 (COX-2) was determined by RT-PCR. An immunofluorescence assay and confocal microscope were used to observe the NF-κB/p65 translocation from the cytoplasm into the nucleus. The likely targets of SL were predicted by molecular docking analysis. Results: SL showed anti-inflammatory activity and reduced the release of inflammatory cytokines including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nitric oxide (NO). The experimental results show that SL suppressed the Ca²⁺ and ROS levels influx in the LPS-induced RAW264.7 cells and alleviated the LPS-induced expression of iNOS and COX-2, the LPS-induced translocation of NF-κB (p65) from the cytoplasm into the nucleus, and the expression of phosphorylated proteins such as p65 and IκBα. Furthermore, molecular docking analysis showed that SL may inhibit inflammatory signaling by competing with LPS to bind TLR4/MD-2 through hydrophobic interactions and by inhibiting IKKβ activation through the hydrogen bonding and hydrophobic interactions. Conclusion: This study demonstrated that SL exerted anti-inflammatory activity via the pathway of NF-κB in RAW264.7 cells.

Gastroprotective Effect of Azilsartan Through Ameliorating Oxidative Stress, Inflammation, and Restoring Hydroxyproline, and Gastrin Levels in Ethanol-Induced Gastric Ulcer

Objective

The present study was designed to evaluate the possible gastroprotective effects of different doses of azilsartan in ethanol-induced gastric ulcers in rats.

Methodology

Forty-eight male adult Wistar rats were used and allocated randomly into four groups: negative control treated with distilled water, positive control treated with ethanol, lansoprazole treated group, and azilsartan (1mg, 5mg, and 10mg/kg) treated group. The treatment protocol was for 15 days, and all the groups except for the negative control group received 1mL of ethanol on the last day 1hr before scarification. Gastric content was collected for measuring the volume, free acidity, and pH. The stomach was used for measuring the gastric lesion area and ulcer index. Blood samples were collected for measuring serum hydroxyproline, gastrin, CRP, TNF-α, MDA, and TAOC. Gastric tissues were sent for histopathological examinations.

Results

Ethanol administration significantly increased gastric lesion, gastric ulcer index, and gastric acidity. Ethanol also decreased serum levels of hydroxyproline and TAOC and increased serum gastrin, CRP, TNF-α, and MDA. Azilsartan 10mg/kg was able to decrease the lesion by 43.6% and increase gastric pH and significantly decreased MDA level. Both 5mg/kg and 10mg/kg azilsartan have successfully restored the level of hydroxyproline, gastrin, and TNF-α. The histopathological finding showed gastroprotection by azilsartan in a dose-dependent manner.

Conclusion

The study revealed that azilsartan possesses a gastroprotective effect. The proposed mechanisms could be increased blood flow to the stomach, antioxidant capacity, and anti-inflammatory activity along with restoring hydroxyproline and gastrin levels. These findings suggest azilsartan as a promising candidate to be tested in a clinical setting.

Anagliptin prevents lipopolysaccharide (LPS)- induced inflammation and activation of macrophages

Sepsis is a multiple organ dysfunction syndrome (MODS) induced by infection, which significantly threatens public health. The overactivation of inflammatory reactions and oxidative stress participate in the pathogenesis of sepsis. Anagliptin, a novel anti-diabetic agent widely applied for the treatment of type II diabetes, has been recently claimed to possess anti-inflammatory properties. Here, the protective effects of anagliptin on lipopolysaccharide (LPS)- stimulated macrophages will be checked to explore the possible pharmacological property of anagliptin on sepsis. The state of oxidative stress was dramatically activated by LPS, accompanied by the upregulation of toll-like receptor 4 (TLR4) and high mobility group box-1 (HMGB-1), as well as the elevated expression of inducible nitric oxide synthase (iNOS) and production of nitric oxide (NO). After treatment with anagliptin, the state of oxidative stress in macrophages was alleviated, with the downregulation of TLR4, HMGB-1, iNOS, and the declined release of NO. The excessive secretion of inflammatory factors, activation of the NF-κB pathway, and promoted expression level of receptor-interacting protein 1 (RIP1) were observed in LPS- stimulated macrophages, all of which were greatly reversed by the introduction of anagliptin. Lastly, the protective properties of anagliptin on LPS- treated macrophages, including the inhibitory effects on inflammation and the NF-κB pathway, were dramatically abolished by the overexpression of RIP1 in macrophages. Collectively, anagliptin prevented LPS-induced inflammation and activation of P338D1 macrophages by repressing the expression level of RIP1.

Azilsartan Suppresses Osteoclastogenesis and Ameliorates Ovariectomy-Induced Osteoporosis by Inhibiting Reactive Oxygen Species Production and Activating Nrf2 Signaling

Osteoporosis is characterized by a decrease in bone mass and destruction of the bone microarchitecture, and it commonly occurs in postmenopausal women and the elderly. Overactivation of osteoclasts caused by the inflammatory response or oxidative stress leads to osteoporosis. An increasing number of studies have suggested that intracellular reactive oxygen species (ROS) are strongly associated with osteoclastogenesis. As a novel angiotensin (Ang) II receptor blocker (ARB), azilsartan was reported to be associated with the inhibition of intracellular oxidative stress processes. However, the relationship between azilsartan and osteoclastogenesis is still unknown. In this study, we explored the effect of azilsartan on ovariectomy-induced osteoporosis in mice. Azilsartan significantly inhibited the receptor activator of nuclear factor-κB ligand (RANKL)-mediated osteoclastogenesis and downregulated the expression of osteoclast-associated markers (Nfatc1, c-Fos, and Ctsk) in vitro. Furthermore, azilsartan reduced RANKL-induced ROS production by increasing the expression of nuclear factor erythroid 2-related factor 2 (Nrf2). Mechanistically, azilsartan inhibited the activation of MAPK/NF-κB signaling pathways, while Nrf2 silencing reversed the inhibitory effect of azilsartan on MAPK/NF-κB signaling pathways. Consistent with the in vitro data, azilsartan administration ameliorated ovariectomy (OVX)-induced osteoporosis, and decreased ROS levels in vivo. In conclusion, azilsartan inhibited oxidative stress and may be a novel treatment strategy for osteoporosis caused by osteoclast overactivation.

Methyl p‑hydroxycinnamate exerts anti‑inflammatory effects in mouse models of lipopolysaccharide‑induced ARDS

Methyl p-hydroxycinnamate (MH), an esterified derivative of p-Coumaric acid exerts anti-inflammatory effects on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Based on these effects, the present study investigated the protective role of MH in a mouse model of LPS-induced acute respiratory distress syndrome (ARDS). The results demonstrated that administration of LPS (5 mg/kg intranasally) markedly increased the neutrophil/macrophage numbers and levels of inflammatory molecules (TNF-α, IL-6, IL-1β and reactive oxygen species) in the bronchoalveolar lavage fluid (BALF) of mice. On histological examination, the presence of inflammatory cells was observed in the lungs of mice administered LPS. LPS also notably upregulated the secretion of monocyte chemoattractant protein-1 and protein content in BALF as well as expression of inducible nitric oxide synthase in the lungs of mice; it also caused activation of p38 mitogen-activated protein kinase (MAPK) and NF-κB signaling. However, MH treatment significantly suppressed LPS-induced upregulation of inflammatory cell recruitment, inflammatory molecule levels and p38MAPK/NF-κB activation, and also led to upregulation of heme oxygenase-1 (HO-1) expression in the lungs of mice. In addition, the ability of MH to induce HO-1 expression was confirmed in RAW264.7 macrophages. Taken together, the findings of the present study indicated that MH may exert protective effects against airway inflammation in ARDS mice by inhibiting inflammatory cell recruitment and the production of inflammatory molecules.

Irbesartan suppresses lipopolysaccharide (LPS)-induced blood-brain barrier (BBB) dysfunction by inhibiting the activation of MLCK/MLC

The basic function of the blood-brain barrier (BBB) is to selectively regulate the infiltration of solutes from the circulating blood into the central nervous system (CNS). Impaired BBB activity is related to brain damage caused by stroke, traumatic injury, neurodegenerative diseases, etc. Comprised of a monolayer of endothelial cells, the integrity of the BBB is determined by the expression of tight junction proteins and the contractile activity of the perijunctional apical actomyosin ring. Irbesartan, an AT1R antagonist, has been widely used for the treatment of hypertension. However, the pharmacological function of Irbesartan in the balance of the BBB is still unknown. In the present study, we performed both in-vivo and in-vitro experiments using lipopolysaccharide (LPS) to explore the mechanism behind the protective effects of Irbesartan against the BBB impairment. The results of our mouse model study revealed that Irbesartan could reduce BBB permeability, restore the expression of Occludin, and suppress the expression of inflammatory mediators, including interleukin-6, monocyte chemoattractant protein-1, and intercellular adhesion molecule-1. Additionally, Irbesartan improved LPS-induced depressive-like behavior. In our in vitro experiments, human brain microvascular endothelial cells (HBMVECs) stimulated with LPS demonstrated decreased endothelial permeability and increased occludin expression in response to Irbesartan treatment. Importantly, we found that the protective effects of Irbesartan were mediated through the NF-κB/MLC/MLCK signaling pathway, as blockage of NF-κB abolished the effects of Irbesartan. Our findings provide a basis for further research into the neuroprotective mechanism of Irbesartan.