Tumor Necrosis Factor-α Secretion Research Articles

The regulatory effect of TiO2 nanotubes loaded with graphene oxide on macrophage polarization in an inflammatory environment

BackgroundExcessive inflammation is a major cause of implant failure. The surface morphology, hydrophilicity, and loading of biomaterials are major properties modulating anti-inflammatory macrophage activation. This paper investigates the regulatory effects of modifying the surface of Titanium dioxide nanotubes (TNTs) with graphene oxide (GO) on the polarization of mouse monocyte macrophages (RAW264.7).MethodsTNT was produced by the anodic oxidation of titanium. GO was subsequently electrodeposited on the TNT to obtain a TNT–GO composite. The samples were characterised through scanning electron microscopy (SEM), Raman spectroscopy, and X-ray diffraction. RAW264.7 cells were separately seeded onto the surface of three groups of samples: pure Ti, TNT, and TNT–GO. Under the condition of lipopolysaccharide stimulation, the influence of the sample surfaces on the gene expression profiles was investigated through RNA sequence analysis. In addition, cell spreading was observed through SEM, cell adhesion and proliferation were analysed using the CCK8 assay, and the expression of inflammation-related factors was investigated by ELISA and cellular immunofluorescence staining. The production of reactive oxygen species (ROS) in the RAW264.7 cells on the surface of the three groups was detected via immunofluorescence staining.ResultsThe CCK8 results indicated that the adhesion and proliferation of the RAW264.7 cells were reduced on the TNT and TNT–GO surfaces. ELISA results revealed significant differences in the pro-inflammatory factors tumour necrosis factor-α and interleukin-6 secretion among the three groups at 24 h (p < 0.05). The secretion of pro-inflammatory factors significantly reduced and the expression of anti-inflammatory factor IL-10 increased on the TNT and TNT–GO surfaces. The RNA sequencing, ELISA, and cell immunofluorescence staining test results suggested that the inflammatory response of M1 polarization was reduced and the M2 polarization of macrophages was induced on the TNT–GO surface, which may be attributed to the reduction in ROS production.ConclusionsUnder lipopolysaccharide stimulation, the inflammatory response of the RAW264.7 cells was reduced and the M2 polarization of macrophages was promoted on the TNT–GO surface, which may be caused by the reduced ROS production. Consequently, the designed TNT–GO material is promising for implants owing to its excellent inflammation regulation ability.

TRPM2 channels are essential for regulation of cytokine production in lung interstitial macrophages.

Interstitial macrophages (IMs) are essential for organ homeostasis, inflammation, and autonomous immune response in lung tissues, which are achieved through polarization to a pro-inflammatory M1 and an M2 state for tissue repair. Their remote parenchymal localization and low counts, however, are limiting factors for their isolation and molecular characterization of their specific role during tissue inflammation. We isolated viable murine IMs in sufficient quantities by coculturing them with stromal cells and analyzed mRNA expression patterns of transient receptor potential (TRP) channels in naïve and M1 polarized IMs after application of lipopolysaccharide (LPS) and interferon γ. M-RNAs for the second member of the melastatin family of TRP channels, TRPM2, were upregulated in the M1 state and functional channels were identified by their characteristic currents induced by ADP-ribose, its specific activator. Most interestingly, cytokine production and secretion of interleukin-1α (IL-1α), IL-6 and tumor necrosis factor-α in M1 polarized but TRPM2-deficient IMs was significantly enhanced compared to WT cells. Activation of TRPM2 channels by ADP-ribose (ADPR) released from mitochondria by ROS-produced H2O2 significantly increases plasma membrane depolarization, which inhibits production of reactive oxygen species by NADPH oxidases and reduces cytokine production and secretion in a negative feedback loop. Therefore, TRPM2 channels are essential for the regulation of cytokine production in M1-polarized murine IMs. Specific activation of these channels may promote an anti-inflammatory phenotype and prevent a harmful cytokine storm often observed in COVID-19 patients.

Molecular incompatibility between pig CD200 and human CD200 receptor in in vitro xenogeneic immune responses.

Overexpression of human CD200 (hCD200) in porcine endothelial cells (PECs) has been reported to suppress xenogeneic immune responses of human macrophages againstporcine endothelial cells. The current study aimed to address whether the above-mentioned beneficial effect of hCD200 is mediated by overcoming the molecular incompatibility between porcine CD200 (pCD200) and hCD200 receptor or simply by increasing the expression levels of CD200 without any molecular incompatibility across the two species. We overexpressed hCD200 or pCD200 using lentiviral vectors with V5 marker in porcine endothelial cells and compared their suppressive activity against U937-derived human macrophage-like cells (hMCs) and primary macrophages. In xenogeneic coculture of porcine endothelial cellsand human macrophage-like cells or macrophages, hCD200-porcine endothelial cells suppressed phagocytosis and cytotoxicity of human macrophages to a greater extent than pCD200-porcine endothelial cells. Secretion of tumor necrosis factor-α, interleukin-1β, and monocyte chemoattractant protein-1 from human macrophages and expression of M1 phenotypes (inducible nitric oxide synthase, dectin-1, and CD86) were also suppressed by hCD200 to a greater extent than pCD200. Furthermore, in signal transduction downstream of CD200 receptor, hCD200 induced Dok2 phosphorylation and suppressed IκB phosphorylation to a greater extent than pCD200. The above data supported the possibility of a significant molecular incompatibility between pCD200 and human CD200 receptor, suggesting that the beneficial effects of hCD200 overexpression in porcine endothelial cellscould be mediated by overcoming the molecular incompatibility across the species barrier rather than by simple overexpression effects of CD200.

Total glucosides of white paeony capsule alleviate articular cartilage degeneration and aberrant subchondral bone remodeling in knee osteoarthritis.

Knee osteoarthritis (KOA) is a prevalent degenerative joint disease that is primarily managed by improving the destroyed cartilage and reversing subchondral bone remodeling. Total glucosides of white paeony (TGP) capsule primarily contains extracts from the white peony root and has been shown to have various pharmacological effects, but its role in KOA still requires comprehensive evaluation. In this study, we aimed to investigate the protective effect of TGP on knee cartilage and subchondral bone, as well as elucidate the underlying molecular mechanisms. The effect of TGP on KOA progression was evaluated in the destabilization of the medial meniscus (DMM)-induced KOA model of mouse and interleukin (IL)-1β-induced KOA model of primary mouse chondrocytes. In vivo and in vitro experiments demonstrated that TGP had a protective effect on the cartilage. Treatment with TGP could induce the synthesis of critical elements in the cartilage extracellular matrix and downregulate the synthesis of degrading enzymes in the extracellular matrix. Regarding the underlying mechanisms, TGP inhibited the phosphorylation and nuclear translocation of p65 by regulating the nuclear factor-kappa B (NF-κB) signaling pathway. In addition, TGP could reduce the secretion of IL-1β, IL-6, and tumor necrosis factor-α (TNF-α). Moreover, it has a sustained effect on coupled subchondral bone remodeling through regulation of the OPG/RANKL/RANK pathway. In conclusion, TGP may protect articular cartilage by downregulating the NF-κB signaling pathway and may support coupled subchondral bone remodeling by regulating OPG/RANKL/RANK signaling pathway in the DMM-induced KOA model of mouse, suggesting a new therapeutic potential for KOA treatment.

Structure and biological activity in vitro of Flagellin and its mutants from Escherichia coli Nissle 1917.

Bacterial flagellin is a potent immunomodulatory agent. Previously, we successfully obtained flagellin from Escherichia coli Nissle 1917 (FliCEcN) and constructed two mutants with varying degrees of deletion in its highly variable regions (HVRs). We found that there was a difference in immune stimulation levels between the two mutants, with the mutant lacking the D2-D3 domain pair of FliCEcN having a better adjuvant effect. Therefore, this study further analyzed the structural characteristics of the aforementioned FliCEcN and its two mutants and measured their levels of Caco-2 cell stimulation to explore the impact of different domains in the HVRs of FliCEcN on its structure and immune efficacy. This study utilized AlphaFold2, SERS (Surface-enhanced Raman spectroscopy), and CD (circular dichroism) techniques to analyze the structural characteristics of FliCEcN and its mutants, FliCΔ174-506 and FliCΔ274-406, and tested their immune effects by stimulating Caco-2 cells in vitro. The resultsindicate that the D2andD3 domainsof FliCEcNhave more complex interactionscomparedtothe D1-D2 domainpair., and thesedomains alsoplay a role in molecular docking with TLR5 (Toll-like receptor 5). Furthermore, FliCΔ274-406 hasmore missing side chain and characteristic amino acid peaks than FliCΔ174-506. The FliCEcN group was found to stimulatehigherlevelsofIL-10 (interleukin 10) secretion, while the FliCΔ174-506 and FliCΔ274-406 groups had higher levels of IL-6 (interleukin 6) and TNF-α (tumor necrosis factor-α) secretion. In summary, the deletion of different domains in the HVRs of FliCEcN affects its structural characteristics, its interaction with TLR5, and the secretion of immune factors by Caco-2 cells.

The association of TNF-alpha secretion and mtDNA copy number in CD14+ monocytes of patients with obesity and CHD.

Mitochondrial dysfunction may be one of the causes of inflammatory activation of monocytes and macrophages, which leads to excessive secretion of inflammatory mediators and the development of chronic inflammation. The study was aimed to evaluate the secretion of inflammatory cytokine tumor necrosis factor-α (TNF-α) in the primary culture of monocytes, and to analyze its relationship with the number of mitochondrial DNA (mtDNA) copies in the blood of patients with coronary heart disease (CHD) and obesity. 108 patients with obesity and concomitant CHD and a control group of 25 participants were included in the study. CD14+ monocytes were isolated by a standard method in a ficoll-urographin gradient, followed by separation using magnetic particles. The number of mtDNA copies was estimated using qPCR. It was demonstrated that the number of mtDNA copies was significantly increased in groups of patients with CHD and obesity + CHD in comparison with control group. mtDNA copy number positively correlated with basal and LPS-stimulated TNF-α secretion, the most significant correlation was found in the group of patients with CHD and obesity. Thus, the change in mtDNA copy number in CD14+ monocytes which indicates the presence of mitochondrial dysfunction, confirm the direct involvement of mitochondria in the violation of the inflammatory response of monocytes revealed in this study as an increased secretion of inflammatory cytokine TNF-α.

Hawthorn Fruit (Crataegus spp.) Polysaccharides Exhibit Immunomodulatory Activity on Macrophages via TLR4/NF-κB Signaling Activation.

The immunostimulatory effects and the involved molecular mechanisms of polysaccharides from hawthorn fruit (Crataegus spp.) have not been well understood. In this study, the chemical composition, monosaccharide composition, uronic acid content, and structural features of hawthorn fruit polysaccharides (HFP) and the two collected fractions were analyzed. Both AF1-2 and AF2 have pectic-like structural features rich in galacturonic acid. AF2 showed superior proinflammatory effects on macrophages which significantly increased the secretion of pro-inflammatory cytokines interleukin-1β, interleukin-6, and tumor necrosis factor-α, but not AF1-2. AF2 was found to activate the nuclear factor-κB signaling pathway with suppressed expression of IκBα but up-regulated expression of p-IκBα and nuclear factor-κB P65. The surface binding site of AF2 on macrophage cells was characterized and toll like receptor-4 was responsible for AF2 induced activation of down-stream nuclear factor-κB signaling pathways. AF2 from hawthorn fruit could be potentially used as a natural source of immunomodulator in functional foods.

Functional genome analysis and anti-Helicobacter pylori activity of a novel bacteriocinogenic Lactococcus sp. NH2-7C from Thai fermented pork (Nham)

Helicobacter pylori, linked to gastric diseases, is targeted for probiotic treatment through bacteriocin production. Bacteriocins have gained recognition for their non-toxic effects on host cells and their ability to combat a wide range of pathogens. This study aimed to taxonomically characterize and evaluate the safety and probiotic properties of the novel species of Lactococcus sp. NH2-7C isolated from fermented pork, as well as its bacteriocin NH2-7C, both in vitro and in silico. Comparative genotypic analysis revealed an average nucleotide identity of 94.96%, an average amino acid identity of 94.29%, and a digital DNA-DNA hybridization value of 63.80% when compared to Lactococcus lactis subsp. lactis JCM 5805T. These findings suggest that strain NH2-7C represents a novel species within the genus Lactococcus. In silico assessments confirmed the non-pathogenic nature of strain NH2-7C and the absence of genes associated with virulence and biogenic amine formation. Whole-genome analysis revealed the presence of the nisA gene responsible for nisin A production, indicating its potential as a beneficial compound with anti-Helicobacter pylori activity and non-toxic characteristics. Probiotic assessments indicated bile salt hydrolase and cholesterol assimilation activities, along with the modulation of interleukin-6 and tumour necrosis factor-α secretion. Strain NH2-7C demonstrated gastrointestinal tolerance and the ability to adhere to Caco-2 cells, affirming its safety and probiotic potential. Additionally, its ability to produce bacteriocins supports its suitability as a functional probiotic strain with therapeutic potential. However, further in vitro and in vivo investigations are crucial to ensure its safety and explore potential applications for Lactococcus sp. NH2-7C as a probiotic agent.

Circ_0035796 depletion inhibits transforming growth factor-β1-induced pulmonary fibrosis in a miR-150-5p/L1CAM-dependent manner

Background: The pathogenesis of pulmonary fibrosis is not fully understood. Previous work has demonstrated the important role of circular RNA (circRNA) in pulmonary fibrosis development. This study aims to analyse the role of circ_0035796 in pulmonary fibrosis and the underlying mechanism. Methods: Human foetal lung fibroblast 1 (HFL1) cells were treated with transforming growth factor-β1 (TGF-β1) to mimic a pulmonary fibrosis cell model. The expression of circ_0035796, microRNA-150-5p (miR-150-5p) and L1 cell adhesion molecule (L1CAM) was determined by quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression of L1CAM, collagen I and fibronectin was detected by Western blot. Cell viability was analysed by CCK-8 assay. Cell proliferation, invasion and migration were investigated by 5-Ethynyl-2’-deoxyuridine (EdU) assay, transwell invasion assay and wound-healing assay, respectively. The secretion of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) was analysed by Enzyme-linked immunosorbent assay (ELISA). Oxidative stress was assessed by detecting Superoxide Dismutase (SOD) activity and Malondialdehyde (MDA) level using commercial kits. The association of miR-150-5p with circ_0035796 and L1CAM was identified by dual-luciferase reporter assay, RNA pull-down assay and RNA immunoprecipitation (RIP) assay. Results: Circ_0035796 and L1CAM expression were dramatically upregulated, while miR-150-5p expression was downregulated in TGF-β1-treated HFL1 cells. TGF-β1 treatment induced cell proliferation, migration, invasion, IL-6 and TNF-α secretion, and oxidative stress, whereas circ_0035796 depletion relieved these effects. In addition, circ_0035796 acted as a sponge of miR-150-5p and miR-150-5p combined with L1CAM. Moreover, miR-150-5p depletion attenuated circ_0035796 knockdown-mediated effects in TGF-β1-exposed HFL1 cells. The regulation of miR-150-5p on TGF-β1-induced fibroblast activation involved the downregulation of L1CAM. Further, circ_0035796 modulated L1CAM expression by interacting with miR-150-5p in TGF-β1-exposed HFL1 cells. Conclusion: Circ_0035796 knockdown ameliorates TGF-β1-induced pulmonary fibrosis through the miR-150-5p/L1CAM axis in vitro.

SFI Reduces the Nucleocytoplasmic Transportation of HMGB1 by Upregulating HDAC3 in LPS-induced RAW264.7 Cells

Shenfu injection (SFI) is widely used for treating endotoxin shock in China. In the present study, to investigate the anti-inflammatory effects of SFI and further explored the potential mechanism of HMGB1 nuclear translocation, we established a vitro cell model provoked by lipopolysaccharide (LPS), observed nucleocytoplasmic translocation of high mobility group box 1 (HMGB1) and the relationship between histone deacetylase 3 (HDAC3) and HMGB1 under SFI intervention. The results showed that SFI upregulated the transcription and expression of HDAC3 in RAW264.7 cells, inhibited the nuclear to cytoplasmic translocation of HMGB1 and its subsequent extracellular release, and depressed the secretion of HMGB1, interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). However, targeted knockdown of HDAC3 induced an increase in HMGB1 translocation to the cytoplasm, and HMGB1 localization was not altered significantly following LPS stimulation. SFI failed to reverse the abnormal localization of HMGB1. These results suggested that SFI may inhibit LPS-induced HMGB1 nuclear translocation in RAW264.7 cells through upregulating HDAC3 expression, thereby inhibiting its downstream pathway and suppressing inflammatory response.

In vitro and in vivo immuno-enhancing effect of fucoidan isolated from non-edible brown seaweed Sargassum thunbergii

Fucoidan has been reported to have various biological activities, such as antioxidant, antitumor and anticoagulant, with various health benefits. However, few studies have been conducted to extract fucoidan from Sargassum thunbergii in terms of its immuno-enhancing activities. This aim of this study was to investigate the immuno-enhancing effect of fucoidan (S3) isolated from Sargassum thunbergii through water extraction and ethanol precipitation in RAW 264.7 macrophages and zebrafish. The results showed that S3 contained a relatively high content of fucose and sulfated polysaccharide. Fourier-transform infrared spectroscopy (FTIR) results show that the characteristic peaks at 845 cm−1 and 1220-1270 cm−1 indicate that S3 contains sulfate groups. In vitro, S3 effectively enhanced nitric oxide (NO) production and phagocytic activity. In addition, the results of the study demonstrated that the secretion of tumor necrosis factor-α, interleukin (IL)-6, IL-1β, and IL-10 was upregulated by nuclear factor kappa B (NF-κB) signaling pathway in a dose-dependent manner. In vivo, S3 activates zebrafish immune responses by promoting secretion of NO and activating the NF-κB pathway. Overall, these results suggest that S3 could be used as a functional ingredient added to nutritional supplements and functional foods.

Gentiopicroside ameliorates CCl4-induced liver injury in mice by regulating the PPAR-γ/Nrf2 and NF-κB/IκB signaling pathways.

This study explored the mechanisms by which gentiopicroside protects against carbon tetrachloride (CCl4)-induced liver injury. Male mice were randomly assigned to the control; CCl4; bifendate 100 mg/kg; or gentiopicroside 25, 50, or 100 mg/kg groups. Both vehicle and drugs were administered intragastrically for 7 days. Mice were administered CCl4 intraperitoneally 1 hour after the last drug dose. After 24 hours, we collected blood and liver samples for testing. Gentiopicroside significantly reduced serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase activities with corresponding reductions in hepatocyte denaturation and necrosis. Gentiopicroside enhanced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and glutathione levels and reduced heme oxygenase 1 (HO-1) activity and malondialdehyde levels in the liver, and these effects were attributed to peroxisome proliferator-activated receptor (PPAR)-γ/nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Meanwhile, gentiopicroside significantly downregulated HO-1 and upregulated SOD and GSH-Px at the mRNA level in the liver. Furthermore, gentiopicroside significantly suppressed serum tumor necrosis factor-α and interleukin-1β secretion, which was associated with the inhibition of nuclear factor-kappa B (NF-κB)/inhibitor of NF-κB (IκB). Gentiopicroside ameliorated CCl4-induced liver injury in mice via the PPAR-γ/Nrf2 and NF-κB/IκB pathways.

Scutellarin alleviates liver injury in type 2 diabetic mellitus by suppressing hepatocyte apoptosis in vitro and in vivo

ObjectiveScutellarin is a primary active composition come from Erigeronbreviscapus. It is well known that scutellarin has anti-inflammatory and antioxidant physiological functions. In this study, we detected the effects of scutellarin on hepatocyte cell apoptosis in type 2 diabetes mellitus (T2DM) rats. MethodsSprague Dawley (SD) (6–8 weeks, 160–180 g) rats were randomly divided into six groups: control, model, scutellarin low-dose, medium-dose, high-dose treatment, and rosiglitazone positive groups; with 10 SD rats in each group (n = 10). The changes of biochemical factors in serum were detected by automatic biochemical instrument, the pathological changes of liver tissue were detected by hematoxylin and eosin (HE) staining, the apoptosis of liver tissue and cells was detected by tissue staining and flow analyzer, and the expression of apoptosis-related factors were determined by qPCR, Western blot and immunohistochemistry in liver tissues or cells. ResultsThe results showed that scutellarin decreased the levels of fasting blood glucose, total cholesterol, triglyceride, and low-density lipoprotein and increased the levels of high-density lipoprotein. Meanwhile, scutellarin decreased the levels of alanine transaminase (ALT) and aspartate transaminase (AST) and improved liver function. In addition, scutellarin suppressed the secretion of interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) and reduced hepatocyte apoptosis. Furthermore, scutellarin inhibited the expression of cleaved Caspase-3, Bax, and cytochrome C (Cyt-C) and promoted the expression of Bcl-2. ConclusionScutellarin can inhibit the apoptotic pathway, thereby relieving T2DM.

Multiple sclerosis with comorbidity depression and its association with vitamin D deficiency in a narrative review of the current literature

Over the past decade, knowledge of the pathophysiology and immunology of multiple sclerosis (MS) and depression, and the complex links to vitamin D (VitD) balance, has increased rapidly. Both diseases are characterized by an imbalance of proinflammatory and antiinflammatory cytokines, increased serum neurofilament light chains (sNfLs), disruption of the blood-brain barrier (BBB), abolition of the physiological function of the various types of microglia (MG), decreased calcidiol-serum levels, and disorders of the gut microbiome in combination with hyperactivity of the hypothalamic-pituitary-adrenal (HPA)-axis/microbiome-gut-brain-axis characterized. In depression, stress initiates cellular and molecular changes in the brain via increased cortisol release in the HPA-axis. Microglial activation and neuronal damage as well as dysregulation of neuroplastic and neurotrophic factors complete the spectrum of pathological damage. It is shown that gut dysbiosis leads to increased gut permeability, which favors endotoxemia and ultimately paves the way to systemic inflammation. A VitD supplementation could restore the balance of microorganisms in the intestine and reduce the inflammatory processes at various levels. VitD promotes regulatory T cell (Treg) proliferation, inhibits the expression of T helper 1 (Th1) cells and Th17 immune cells, and inhibits proinflammatory interleukin-17 (IL-17). 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] reduces also the secretion of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). Increased calcitriol levels lead to a reduction in MG activation, oxidative stress, and lower BBB permeability. An early, permanent, daily sufficient VitD supplementation as an add-on therapy under control of the serum 25-hydroxyvitamin D [s25(OH)D] levels is an essential therapeutic tool to slow down the disability caused by MS and thereby primarily prevent or reduce the stress and subsequently the manifestation of depression. Through the future continuous measurement of the biomarkers serum neurofilament ligth chains and glial fibrillary acidic proteins as well as the s25(OH)D level in MS and comorbidity depression, future therapy successes or failures can be avoided.

Fucoxanthin, a marine derived carotenoid, attenuates surgery-induced cognitive impairments via activating Akt and ERK pathways in aged mice

BackgroundFucoxanthin is the most abundant marine carotenoid derived from brown seaweeds, possesses antioxidant, anti-inflammatory, and neuroprotective properties, and might be benefit for the treatment of neurological disorders. Post-operative cognitive dysfunction (POCD) is a neurological symptom with learning and memory impairments, mainly affecting the elderly after surgery. However, there is no effective treatments for this symptom. PurposesIn this study, we evaluated the neuroprotective effects of fucoxanthin against POCD in aged mice after surgery. Study design and methodsThe animal model of POCD was established in 12 – 14 month aged mice with a laparotomy. Curcumin was used as a positive control. The beneficial effects of fucoxanthin on POCD was analyzed by behavioral tests. Pro-inflammatory cytokines were measured by Enzyme-linked Immunosorbent Assay (ELISA). And the expressions of key proteins in the Akt and ERK signaling pathways were analyzed by Western blotting analysis. The morphology of microglial cells and astrocytes was explored by immunohistochemical staining. The activity of antioxidant superoxide dismutase (SOD) and catalase (CAT) were measured by anti-oxidative enzyme activity assays. ResultsFucoxanthin at 100 – 200 mg/kg significantly attenuated cognitive dysfunction, with a similar potency as curcumin, in aged mice after surgery. In addition, fucoxanthin and curcumin significantly increased the expression of pAkt, prevented the activation of microglial cells and astrocytes, and inhibited the secretion of pro-inflammatory interleukin-1β (IL - 1β) and tumor necrosis factor-α (TNF-α). Furthermore, fucoxanthin and curcumin elevated the ERK pathway and potently increased the activity of antioxidant enzymes. Most importantly, U0126, an inhibitor of the ERK pathway, and wortmannin, an inhibitor of the Akt pathway, significantly abolished the cognitive-enhancing effects, as well as the inhibition of neuroinflammation and the reduction of oxidative stress, induced by fucoxanthin in aged mice after surgery. ConclusionFucoxanthin might be developed as a functional food or drug for the treatment of POCD by inhibiting neuroinflammation and enhancing antioxidant capacity via the activation of the Akt and ERK signaling pathways.

The Protective Effect and Mechanism of a Phytochemical Extract from the Wild Vegetable Shutou (Crateva unilocularis Buch.) against Acetaminophen-Induced Liver Injury in Mice.

Acetaminophen (APAP) abuse is a common public health problem which can cause severe liver damage. However, strategies for dealing with this situation safely and effectively are very limited. The goal of the current work was to evaluate the protection and potential molecular mechanisms of an ethanol extract from shoots of the wild vegetable shutou (Crateva unilocularis Buch.) (ECS) against APAP-induced liver damage in mice. Mice orally received ECS for seven days (300 or 600 mg/kg b.w. per day) before being intraperitoneally injected with APAP (250 mg/kg). Results exhibited that ECS obviously decreased the content of alkaline phosphatase, alanine aminotransferase, aspartate transaminase, and malondialdehyde (p < 0.05). Catalase and superoxide dismutase were notably restored (p < 0.05), and the content of reduced glutathione was obviously increased (p < 0.05). Moreover, ECS significantly inhibited the secretion of interleukin-1β and tumor necrosis factor-α (p < 0.05). Further analyses of the mechanisms showed that ECS may alleviate oxidative stress in the liver by increasing the expression of the nuclear factor erythroid-2-related factor 2 and NADH quinone oxidoreductase 1 proteins, and may suppress liver inflammation by inhibiting the expression of the phosphorylated-inhibitor kappa B alpha/inhibitor kappa B alpha, phosphorylated-nuclear factor κB/nuclear factor κB, and cyclooxygenase-2 proteins. Meanwhile, ECS inhibited hepatocyte apoptosis by enhancing B-cell lymphoma gene 2 and suppressing Bcl-2-associated X protein. In summary, ECS may be used as a dietary supplement to prevent the liver damage caused by APAP abuse.

Effects of Extracts of Two Selected Strains of Haematococcus pluvialis on Adipocyte Function.

Recently, microalgae are arousing considerable interest as a source of countless molecules with potential impacts in the nutraceutical and pharmaceutical fields. Haematococcus pluvialis, also named Haematococcus lacustris, is the largest producer of astaxanthin, a carotenoid exhibiting powerful health effects, including anti-lipogenic and anti-diabetic activities. This study was carried out to investigate the properties of two selected strains of H. pluvialis (FBR1 and FBR2) on lipid metabolism, lipolysis and adipogenesis using an in vitro obesity model. FBR1 and FBR2 showed no antiproliferative effect at the lowest concentration in 3T3-L1 adipocytes. Treatment with FBR2 extract reduced lipid deposition, detected via Oil Red O staining and the immunocontent of the adipogenic proteins PPARγ, ACLY and AMPK was revealed using Western blot analysis. Extracts from both strains induced lipolysis in vitro and reduced the secretion of interleukin-6 and tumor necrosis factor-α. Moreover, the FBR1 and FBR2 extracts improved mitochondrial function, reducing the levels of mitochondrial superoxide anion radical and increasing mitochondrial mass compared to untreated adipocytes. These findings suggest that FBR2 extract, more so than FBR1, may represent a promising strategy in overweight and obesity prevention and treatment.

Immunomodulatory effects of seed peptide lunasin in RAW264.7 macrophages in obese microenvironments

In adiposity, immune cells infiltrate adipose tissues, especially macrophages, forming chronic inflammation. This study aimed to investigate the mechanism of lunasin regulating immune functions of RAW264.7 macrophages in obesity-related conditions. Lipopolysaccharide (LPS) triggered an acute inflammation, and adipocyte-conditioned medium (Ad-CM) and co-cultures of RAW264.7 macrophages and 3T3-L1 adipocytes were used to mimic obese microenvironments. Lunasin protected the vitality of RAW cells and suppressed leptin secretion in Ad-CM. In LPS, lunasin reduced 47% of 2′,7′-dichlorodihydrofluorescein diacetate (DCF-DA) staining, 28% of nitric oxide production, and 27% of tumor necrosis factor-α secretion in LPS-stimulated co-culture, while there were opposing effects in Ad-CM and co-culture without LPS. Moreover, LPS-stimulated migration was inhibited at 44% by lunasin, while Ad-CM-declined 49% of migration. Lunasin increased 21% and 42% of phagocytosis in LPS and Ad-CM challenges. Overall, the study first revealed that lunasin exerted immunomodulation in macrophages against LPS-stimulated inflammation but boosted immune functions in obesity-related microenvironments.

The Functions of Cholera Toxin Subunit B as a Modulator of Silica Nanoparticle Endocytosis.

The gastrointestinal tract is the main target of orally ingested nanoparticles (NPs) and at the same time is exposed to noxious substances, such as bacterial components. We investigated the interaction of 59 nm silica (SiO2) NPs with differentiated Caco-2 intestinal epithelial cells in the presence of cholera toxin subunit B (CTxB) and compared the effects to J774A.1 macrophages. CTxB can affect cellular functions and modulate endocytosis via binding to the monosialoganglioside (GM1) receptor, expressed on both cell lines. After stimulating macrophages with CTxB, we observed notable changes in the membrane structure but not in Caco-2 cells, and no secretion of the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) was detected. Cells were then exposed to 59 nm SiO2 NPs and CtxB sequentially and simultaneously, resulting in a high NP uptake in J774A.1 cells, but no uptake in Caco-2 cells was detected. Flow cytometry analysis revealed that the exposure of J774A.1 cells to CTxB resulted in a significant reduction in the uptake of SiO2 NPs. In contrast, the uptake of NPs by highly selective Caco-2 cells remained unaffected following CTxB exposure. Based on colocalization studies, CTxB and NPs might enter cells via shared endocytic pathways, followed by their sorting into different intracellular compartments. Our findings provide new insights into CTxB's function of modulating SiO2 NP uptake in phagocytic but not in differentiated intestine cells.

Exploring the mechanism of Icariin in the treatment of depression through BDNF-TrkB pathway based on network pharmacology.

Depression has increasingly become a disease that seriously harms people's mental health around the world. Icariin is the main active component of Epimedii Herba and effective on protecting the central nervous system. The purpose of this study was to explore the mechanism of icariin against depression based on network pharmacology and molecular docking. The potential targets related to icariin and depression were obtained by accessing network databases. The Metascape database was used for the enrichment analysis of GO function and KEGG pathways. A common target-pathway network was constructed using Cytoscape 3.9.0 software. Schrödinger Maestro 12.8 was adopted to evaluate the binding ability of icariin to core targets. Mice were induced by the chronic unpredictable mild stress (CUMS) model, and the prediction results of this study were verified by in vivo experiments. A total of 109 and 3294 targets were identified in icariin and depression, respectively. The common target-pathway network was constructed, and 7 core target genes were obtained. The molecular docking results of the 7 core target genes with icariin showed good affinity. In a CUMS-induced depression model, we found that icariin could effectively improve depression-like behavior of mice, increase the expression of monoamine neurotransmitters 5-hydroxytryptamine, dopamine, and norepinephrine, decrease the secretion of inflammatory factors tumor necrosis factor-α, interleukin-6, and interleukin-1β, and upregulate the relative expression levels of BDNF, p-TrkB/TrkB, p-Akt/Akt, p-CREB/CREB, MAPK3, MAPK1, Bcl-2, EGFR, and mTOR. The results suggest that icariin has certain antidepressant effects, and may be mediated by the BDNF-TrkB signaling pathway. It provides new ideas for the treatment of depression in the future.