Secretion Of Inflammatory Cytokines Research Articles

The Protective Effects of Ganoderma lucidum Active Peptide GLP4 on Lung Injury Induced by Cadmium Poisoning in Mice.

Ganoderma triterpenes and spore powder have shown promising results in mitigating cadmium-induced renal and hepatic injuries. Ganoderma lucidum active peptide GLP4 is a natural protein with dual antioxidant activities derived from the mycelium of Ganoderma lucidum. However, its efficacy in alleviating cadmium-induced lung injury remains unexplored. This study aims to investigate the protective effects of GLP4 against cadmium-induced lung injury in mice. Mice were exposed to cadmium chloride via nebulization to induce lung injury. The protective effect of GLP4 was assessed by measuring the total cell count in BALF, levels of inflammatory cytokines, and the expression of NLRP3 in lung tissues a through histopathological examination of lung tissue changes. The results showed that GLP4 significantly mitigated histopathological damage in lung tissues, decreased the secretion of inflammatory cytokines, and reduced the expression of NLRP3, which was elevated in cadmium-exposed mice. In vitro studies further revealed that GLP4 inhibited the cadmium-induced activation of the NLRP3 inflammasome. Notably, acute cadmium exposure by the respiratory tract did not affect the liver and kidneys of the mice. The findings suggest that GLP4 reduces cadmium-induced lung injury in mice by inhibiting the activation of the NLRP3 inflammasome, which provides a theoretical foundation for using Ganoderma lucidum as a preventive and therapeutic agent against cadmium poisoning.

Xanthoangelol alleviates ischemic stroke injury by inhibiting the inflammatory activation of microglia

BackgroundLocal inflammation induced by microglial activation plays a significant role in the pathological process of cerebral ischemia. Angelica keiskei (Miq.) Koidz., a traditional botanical drug, can be used as a diuretic, laxative or galactagogue. Xanthoangelol (XA), an active chalcone compound from the aerial part of Angelica keiskei, has anti-inflammatory effects in the peripheral tissues. However, its effect against neuroinflammation is yet unclear. ObjectiveThe present study aims to investigate whether XA could mitigate ischemic stroke damage through attenuating neuroinflammation due to microglia activation. MethodsMiddle cerebral artery occlusion/reperfusion (MCAO/R) induced cerebral ischemia and oxygen-glucose deprivation/reperfusion (OGD/R) or lipopolysaccharide (LPS)-stimulated BV2 microglia cells were utilized to evaluate XA's protection against ischemic injury and neuroinflammation. The severity of brain injury was assessed using 2, 3, 5-triphenyltetrazolium chloride (TTC) staining and neurological assessment. The expressions of inflammatory cytokines were quantified by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). Reactive oxygen species (ROS) were assessed using dichlorodihydrofluorescein diacetate (DCF-DA) staining. NF-κB p65 nuclear translocation was confirmed by immunofluorescence (IF) staining. The expressions of proteins were quantified by Western blotting. ResultsXA was efficacious in reducing infarct size and improving neurological function in MCAO/R mice. In ischemic brain tissue, XA reduced microglial activation and proinflammatory cytokine expression. In lipopolysaccharide (LPS) and OGD/R-induced cell models, XA suppressed the production of ROS and decreased the secretion of inflammatory cytokines. Additionally, XA suppressed the nuclear translocation and phosphorylation of NF-κB p65 and blocked the activation of NLR family pyrin domain containing 3 (NLRP3) inflammasome. The protection of XA against MCAO/R-induced damages was not attenuated in TLR4−/− and MD2−/− mice. Mito-TEMPO treatment reversed XA's anti-inflammatory properties in OGD/R-induced BV2 cells. ConclusionXA attenuates ischemic stroke injury by suppressing microglial inflammatory responses. This efficacy is tied to its antioxidant activity and is independent of Toll-like receptor 4 (TLR4) or myeloid differentiation protein 2 (MD2).

Bone protective effects of the polysaccharides from Grifola frondosa on ovariectomy-induced osteoporosis in mice via inhibiting PINK1/Parkin signaling, oxidative stress and inflammation

BackgroundPolysaccharides from Grifola frondosa(GFP) have gained worldwide attention owing to their promising biological activities and potential health benefits. PurposeThis study aimed to investigate the effects of GFP on alleviation of osteoporosis in ovariectomized (OVX) mice and examine the underlying mechanism. MethodA mouse model of postmenopausal osteoporosis was established by OVX method, Forty eight C57BL/6 female mice were randomly divided into Normal group, OVX alone (Model group, n = 8), OVX + 10 mg/kg GFP (GFP-L group, n = 8), OVX + 20 mg/kg GFP (GFP-M group, n = 8), OVX + 40 mg/kg GFP (GFP-H group, n = 8), OVX + 10 mg/kg Estradiol valerate (Positive group, n = 8). ResultsThe results showed that compared with Model group, the concentrations of interleukin (IL)-1β, interleukin (IL)-6 and Tumor necrosis factor-α (TNF-α) were significantly reduced, the activity of superoxide dismutase (SOD) and glutathione (GSH) were significantly increased, the content of myeloperoxidase (MPO) and malondialdehyde (MDA) were significantly reduced, and the proteins levels of PINK1, Parkin, Beclin-1 and LC3-II were significantly decreased in the GFP groups. ConclusionThis study demonstrates that GFP alleviates ovariectomy-induced osteoporosis via reduced secretion of inflammatory cytokines, improvement in the oxidative stress status in the body, and inhibition of the PINK1/Parkin signaling pathway.

Mangiferin attenuates lipopolysaccharide-induced neuronal injuries in primary cultured hippocampal neurons.

Mangiferin, a naturally occurring potent glucosylxanthone, is mainly isolated from the Mangifera indica plant and shows potential pharmacological properties, including anti-bacterial, anti-inflammation, and antioxidant in sepsis-induced lung and kidney injury. However, there was a puzzle as to whether mangiferin had a protective effect on sepsis-associated encephalopathy. To answer this question, we established an in vitro cell model of sepsis-associated encephalopathy and investigated the neuroprotective effects of mangiferin in primary cultured hippocampal neurons challenged with lipopolysaccharide (LPS). Neurons treated with 20 μmol/L or 40 μmol/L mangiferin for 48 h can significantly reverse cell injuries induced by LPS treatment, including improved cell viability, decreased inflammatory cytokines secretion, relief of microtubule-associated light chain 3 expression levels and several autophagosomes, as well as attenuated cell apoptosis. Furthermore, mangiferin eliminated pathogenic proteins and elevated neuroprotective factors at both the mRNA and protein levels, showing strong neuroprotective effects of mangiferin, including anti-inflammatory, anti-autophagy, and anti-apoptotic effects on neurons in vitro.

Esaxerenone Inhibits Interferon-γ Induced Pyroptosis of Macrophages in the Lungs of Aldosterone-treated Mice.

Lung immune cells such as lymphocytes and macrophages can induce an inflammatory response due to the activation of mineralocorticoid receptor (MR), which is manifested by the infiltration of inflammatory cells and the secretion of inflammatory cytokines and subsequent apoptosis, pyroptosis and necrosis of intrinsic lung cells and immune cells. Macrophages are immune cells that are abundant in the lung and act as the first line of defense against pathogens but are also aggravating factors of infection. The activation of the renin-angiotensin-aldosterone system (RAAS), especially aldosterone-stimulated MR activation, can induce macrophage and CD8+T cell aggregation and the secretion of cytokines such as tumor necrosis factor-α (TNF-α) and interferon-gamma (IFN-γ). Increased IFN-γ secretion can induce macrophage pyroptosis and the release of interleukin 1-β (IL-1β), aggravating lung injury. In this study, lung injury in C57BL/6 mice was induced by subcutaneous micro-osmotic pump infusion of aldosterone. After 12weeks of administration, the kidney, heart, blood vessels and lungs all showed obvious inflammatory injury, which manifested as rapid accumulation of macrophages. The overexpression of IFN-γ in the lungs of aldosterone-treated mice and the stimulation of MH-S and RAW264.7 alveolar macrophages (AMs) with aldosterone in vitro showed that IFN-γ induced pyroptosis of macrophages via the activation of the inflammasome, and the MR blocker esaxerenone effectively inhibited this effect and alleviated lung injury. In addition, IFN-γ secreted by CD8+T cells is associated with macrophage pyroptosis. In conclusion, the inhibition of macrophage pyroptosis can effectively alleviate lung injury.

Loose suture-related ocular surface inflammation and activation of conjunctiva-associated lymphoid tissue in patients after keratoplasty

The purpose of this study is to evaluate loose suture-related inflammation and activation of conjunctiva-associated lymphoid tissue (CALT) in patients after keratoplasty. The patients who were treated with keratoplasty at the First Affiliated Hospital of Harbin Medical University between 2015 and 2022 were recruited into the study. We evaluated the time and location of loose suture development in patients after keratoplasty. In addition, in vivo confocal microscopy was used to evaluate the activation of CALT and the accumulation of inflammatory cells around loose sutures. Meso Scale Discovery assay detection kits were used to evaluate the inflammatory cytokines in the tears of patients before and after the loose suture was removed. In this study, we collected the information from 212 cases (212 eyes) who had PK (126 eyes) and DALK-treated (86 eyes) for corneal transplantation, including 124 males and 88 females, aged 14–84 years old. The average age was 50.65 ± 16.81 years old. Corneal sutures were more prone to loose at 3 months and 6 months after keratoplasty, and the frequent sites were at 5 and 6 o’clock. An increased number of inflammatory cells could be observed around the loose sutures than normal sutures (P < 0.001). In CALT, the density of diffuse lymphocytes (P < 0.001), follicles (P < 0.001), and parafollicular lymphocytes (P < 0.001) were higher and the central reflection of the follicles (P < 0.001) was stronger when suture loosening happened. The levels of inflammatory cytokines such as IL-1β (P = 0.003), IL-8 (P = 0.012), and TNF-α (P < 0.001) were higher in the tears of the patients with loose sutures. The activation of CALT was partly settled after removing the loose sutures. In conclusion, loose sutures after corneal transplantation can lead to increased infiltration of inflammatory cells, activation of CALT, and increased secretion of inflammatory cytokines in the tears of patients. Regular follow-up to identify and solve the problem in time can avoid suture-related complications.

Abstract SoA2-01: Cellular senescence: The senescence-associated secretory phenotype (SASP) and immunity

Abstract Cellular senescence is a stress-induced program following aberrant oncogene activation or administration of cancer therapies, including chemotherapeutic agents and CDK4/6 inhibitors commonly used for treating advanced breast cancers, that results in the proliferative arrest of damaged cells and induction of the senescence associated secretory phenotype (SASP). The SASP involves secretion of inflammatory cytokines and chemokines and upregulation of immunomodulatory cell surface molecules on senescent cells that can promote their clearance by the immune system and tumor resolution. However, if left unchecked, the chronic SASP can also lead to immune suppression and further tissue damage that drives tumor dissemination and metastasis. Here we will discuss our efforts to understand how the SASP can promote anti-tumor immunity and immunotherapy activity in some cancer contexts yet in others immune suppression and tumor promotion. Our findings in other solid tumor contexts demonstrate that the tissue microenvironment has a profound impact of the type of SASP program activated and SASP-mediated immune responses produced and suggest further therapeutic interventions to remodel the SASP for immune control of cancer. Moreover, our results in other hormone-driven cancers suggest that CDK inhibitor and chemotherapy regimens produce different SASPs and resulting effects on myeloid cell and lymphocyte phenotypes that could explain their varying effects on anti-tumor immunity and treatment outcomes. Collectively these findings have important implications for breast cancer treatment and pave the path for rationale combination therapies with senescence-inducing agents to achieve immune control in breast and other immunologically “cold” solid tumor malignancies that are generally unresponsive to current immunotherapy regimens. Citation Format: M. Ruscetti. Cellular senescence: The senescence-associated secretory phenotype (SASP) and immunity [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr SoA2-01.

Berberine alleviates diabetic retinopathy by regulating the Th17/Treg ratio

BackgroundDiabetic retinopathy (DR) stands as a prominent complication of diabetes. Berberine (BBR) has reported to be effective to ameliorate the retinal damage of DR. Studying the potential immunological mechanisms of BBR on the streptozotocin (STZ) induced DR mouse model will explain the therapeutic mechanisms of BBR and provide theoretical basis for the clinical application of this drug. MethodsC57BL/6 J mice were induced into a diabetic state using a 50 mg/(kg·d) dose of STZ over a 5-day period. Subsequently, they were subjected to a high-fat diet (HFD) for one month. Following a 5-week treatment with 100 mg/(kg·d) BBR, the concentrations of inflammatory factors in the mice's peripheral blood were determined using an enzyme-linked immunosorbent assay (ELISA). Hematoxylin-eosin staining was employed to scrutinize pathological changes in the mice's retinas, while flow cytometry assessed the proportions of T-lymphocyte subsets and the activation status of dendritic cells (DCs) in the spleen and lymph nodes. CD4+T cells and DC2.4 cell lines were utilized to investigate the direct and indirect effects of BBR on T cells under high glucose conditions in vitro. ResultsFollowing 5 weeks of BBR treatment in the streptozotocin (STZ) mouse model of DR, we observed alleviation of retinal lesions and a down-regulation in the secretion of inflammatory cytokines, namely TNF-α, IL-1β, and IL-6, in the serum of these mice. And in the spleen and lymph nodes of these mice, BBR inhibited the proportion of Th17 cells and promoted the proportion of Treg cells, thereby down-regulating the Th17/Treg ratio. Additionally, in vitro experiments, BBR directly inhibited the expression of the transcription factor RORγt and promoted the expression of the transcription factor Foxp3 in T cells, resulting in a down-regulation of the Th17/Treg ratio. Furthermore, BBR indirectly modulated the Th17/Treg ratio by suppressing the secretion of TNF-α, IL-1β, and IL-6 by DCs and enhancing the secretion of indoleamine 2,3-dioxygenase (IDO) and transforming growth factor-beta (TGF-β) by DCs. This dual action inhibited Th17 cell differentiation while promoting Treg cells. ConclusionOur findings indicate that BBR regulate T cell subpopulation differentiation, reducing the Th17/Treg ratio by directly or indirectly pathway. This represents a potential therapeutic avenue of BBR for improving diabetic retinopathy.

Abstract 3046: Macrophage-smooth Muscle Cell Interactions In Atherosclerotic Foam Cell Formation

Background: A hallmark of atherosclerosis is uncontrolled uptake of atherogenic lipoproteins by artery wall cells that accumulate large amounts of cholesteryl esters (“foam cells”). While smooth muscle cells (SMCs) and macrophages are in close proximity in lesions and contribute to cholesterol accumulation, whether these cells influence each other’s tendency to form foam cells is not clearly established. Hypothesis: Direct and indirect interactions between SMCs and macrophages promote foam cell formation by both cell types. Method: Human vascular SMCs were seeded onto macrophages to mimic direct macrophage-SMC interactions (n=5). Alternatively, conditioned media generated from human macrophages or SMCs with or without lipoprotein exposure was incubated with the alternate cell type (n=3). Aggregated lipoproteins were added in both models to induce cellular cholesterol accumulation. Intracellular cholesterol was quantified to compare lipoprotein uptake in cocultures relative to monocultures. Crosstalk based on CellChat analysis using single-cell RNA sequencing data from human coronary samples was performed to identify potential factors responsible for foam cell development (n=3). One-way ANOVA was used for statistical analysis. Result: SMCs showed a 4-fold (+/-0.3, p=0.002) increase in cell cholesterol accumulation when in direct contact with macrophages and a 3-fold (+/- 0.3, p&lt;0.0001) increase when exposed to the conditioned media from macrophage foam cells. In contrast, macrophages showed a 3-fold reduction (+/- 0.3, p=0.001) in intracellular cholesterol accumulation when in direct contact with SMCs and a 2-fold reduction (+/-0.2, p=0.0005) when exposed to SMC foam cell-conditioned media. CellChat analysis suggested macrophage foam cells but not macrophage non-foam cells promote SMC foam cell formation by secretion of inflammatory cytokines, and that SMCs promote macrophage foam cell formation by secretion of extracellular matrix components. Conclusion: Our study provides novel understanding of how macrophage-SMC interactions influence macrophage and SMC foam cell formation. Further studies will be presented examining the role of SMC extracellular matrix proteins and macrophage-secreted cytokines on foam cell formation.

NKCC1-dependent K+ influx inhibits NLRP3 inflammasome activation and prevents intestinal epithelial cell injury

Background: Loss of function mutations in SLC12A2, the gene encoding the Na+-K+-2Cl− cotransporter (NKCC1) are associated with autoinflammatory and severe chronic inflammation in multiple organs. NLRP(s) are a family of cytosolic sensors that initiate the innate immune response. Once activated, NLRP(s) form inflammasomes, which are multi-protein complex that sense danger signals, damaged and infected cells. Assembly of the inflammasome mediates caspases-1 activation and the production of the proinflammatory cytokines IL-1β and IL-18 and initiates an inflammatory cell death process called pyroptosis. Aberrant activation of NLRP3 and other inflammasomes leads to a variety of autoimmune and chronic inflammatory diseases. Here we ask whether loss of NKCC1 function affects inflammasome activation in intestinal epithelial cells. Methods: Wild-type intestinal epithelial cells (IEC) and CRISPR/Cas9 NKCC1-deleted clones were tested for inflammasome activation. WT and NKCC1-deficient clones were treated with nigericin, ATP or ouabain to activate the inflammasome. Conditioned media, whole cell lysate and fixed cells were collected at different time points and analyzed by immunoblotting, immunofluorescence, and ELISA (to measure cytokine release). Inflammasome-induced pyroptosis was assessed by measuring LDH release in the supernatant and gasdermine D cleavage by immunoblotting. Results: Loss of NKCC1 function induces inflammasome activation by increasing IL-1β secretion in intestinal epithelial cells. Prolong inflammatory cytokine secretion led to increased pyroptosis-mediated cell death. Loss of NKCC1 mediates NLRP3 inflammasome activation by compromising K+ influx. NLRP3 agonists increase the interaction and localization of WNK1 and SPAK kinases with the NLRP3 inflammasome complex. Conclusions: NKCC1 regulates inflammatory cytokines secretion. Loss of NKCC1 inhibits K+ and Cl− inward fluxes, which in turn activate NLRP3 inflammasome. Loss of NKCC1 function is a previously unknown mechanism that causes aberrant inflammasome activation. GM118944 DK093501. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Advances in Myelofibrosis Management: New Janus Kinase Inhibitors Beyond Ruxolitinib

Myelofibrosis is a myeloproliferative neoplasm characterized by the buildup of fibrous scar tissue in the bone marrow occurring secondary to the secretion of inflammatory cytokines, leading to cytopenias, dysfunctional hematopoiesis, and constitutional symptoms. One of the pathologic mechanisms that underlies myelofibrosis is aberrant activation of the Janus kinase (JAK)-STAT pathway. Targeting the JAK-STAT pathway via JAK inhibition can lead to significant improvements in spleen volume reduction and symptom improvement in intermediate- and high-risk myelofibrosis. The first JAK inhibitor approved by the US Food &amp; Drug Administration was ruxolitinib in 2011. Recently, there have been additional JAK inhibitors approved for myelofibrosis, including fedratinib, pacritinib, and momelotinib. The emergence of these new therapies offers additional treatment options for patients with myelofibrosis. This article reviews the pharmacology, efficacy, safety, dosing, administration, and implications for advanced practitioners of newer JAK inhibitors (fedratinib, pacritinib, and momelotinib) in the treatment of myelofibrosis.

Effect of Low-Intensity Pulsed Ultrasound on Macrophage Properties and Fibrosis in the Infrapatellar Fat Pad in a Carrageenan-Induced Knee Osteoarthritis Rat Model.

In the progression of knee osteoarthritis (KOA), fibrosis of the infrapatellar fat pad (IFP) is a key pathological change. Low-intensity pulsed ultrasound (LIPUS) inhibits IFP fibrosis by decreasing the gene expression and activity of hypoxia-inducible factor (HIF-1α), which is a protein involved in IFP fibrosis in KOA rat models. On the other hand, macrophages play an important role in the progression of fibrosis in various tissues, and LIPUS irradiation suppresses macrophage infiltration and inflammatory cytokine secretion. However, whether LIPUS suppresses macrophage polarity and IFP fibrosis in KOA remains unclear. Therefore, we investigated the effect of LIPUS on macrophage polarity and IFP fibrosis. A KOA model was created by injecting carrageenin into the bilateral knee joints of Wistar rats (eight weeks old). Tissues were harvested over time for histological and molecular biological analysis. The KOA model was also subjected to LIPUS irradiation for two weeks following the injection of carrageenin. RM-4-positive cells were widely distributed in IFP two weeks after carrageenin administration, but M2 macrophages were significantly increased, and the Sirius red area was decreased in the LIPUS-irradiated group compared with those in the non-irradiated group. The gene expression of M1 macrophage markers was significantly decreased and that of M2 macrophage markers was significantly increased in the LIPUS-irradiated group. The expression of transforming growth factor-β (TGF-β) and type 1 collagen was also significantly decreased. These results suggest that LIPUS may serve as a novel approach for the treatment of KOA through its effect on M1 macrophages and suppression of TGF-β expression.

A recombinant plasmid encoding human hepatocyte growth factor promotes healing of combined radiation-trauma skin injury involved in regulating Nrf2 pathway in mice.

Combined radiation-trauma skin injury represents a severe and intractable condition that urgently requires effective therapeutic interventions. In this context, hepatocyte growth factor (HGF), a multifunctional growth factor with regulating cell survival, angiogenesis, anti-inflammation and antioxidation, may be valuable for the treatment of combined radiation-trauma injury. This study investigated the protective effects of a recombinant plasmid encoding human HGF (pHGF) on irradiated human immortalized keratinocytes (HaCaT) cells in vitro, and its capability to promote the healing of combined radiation-trauma injuries in mice. The pHGF radioprotection on irradiated HaCaT cells in vitro was assessed by cell viability, the expression of Nrf2, Bcl-2 and Bax, as well as the secretion of inflammatory cytokines. In vivo therapeutic treatment, the irradiated mice with full-thickness skin wounds received pHGF local injection. The injuries were appraised based on relative wound area, pathology, immunohistochemical detection, terminal deoxynucleotidyl transferase dUTP nick end labelling assay and cytokine content. The transfection of pHGF increased the cell viability and Nrf2 expression in irradiated HaCaT cells. pHGF also significantly upregulated Bcl-2 expression, decreased the Bax/Bcl-2 ratio and inhibited the expression of interleukin-1β and tumor necrosis factor-α in irradiated cells. Local pHGF injection in vivo caused high HGF protein expression and noticeable accelerated healing of combined radiation-trauma injury. Moreover, pHGF administration upregulated Nrf2, vascular endothelial growth factor, Bcl-2 expression, downregulated Bax expression and mitigated inflammatory response. In conclusion, the protective effect of pHGF may be related to inhibiting apoptosis and inflammation involving by upregulating Nrf2. Local pHGF injection distinctly promoted the healing of combined radiation-trauma injury and demonstrates potential as a gene therapy intervention for combined radiation-trauma injury in clinic.

Unraveling ferroptosis in osteogenic lineages: implications for dysregulated bone remodeling during periodontitis progression

Periodontitis is a highly prevalent disease characterized by inflammation and destruction of tooth-supporting tissues that leads to tooth loss in extreme situations. Elucidating the underlying mechanisms of periodontitis pathogenesis and progression will establish the groundwork for developing effective treatment strategies. Recently, evidence concerning the role of ferroptosis in periodontitis progression has emerged. Osteogenic lineage cells are key regulators of bone remodeling. Osteogenic cell death, as observed in experimental periodontitis models, disrupts the balance between bone resorption and bone formation. However, whether the osteogenic lineage undergoes ferroptosis during periodontitis and the corresponding effect on periodontitis progression remain elusive. Here, we investigated cell-specific ferroptosis within the alveolar bone in a murine periodontitis model. Through immunofluorescence double staining and immunohistochemistry, we identified ferroptotic osteocytes and osteoblasts in inflammatory alveolar bone. Next, in vivo administration of erastin or liproxstatin-1 was conducted to either induce or inhibit ferroptosis, respectively. Severe bone resorption and inflammation, accompanied by increased osteoclast formation and impaired osteogenic potential were detected following ferroptosis activation. Subsequently, we carried out in vitro experiments on osteocytes and further verified that ferroptosis enhanced the osteocytic expression of RANKL and IL-6. These findings suggest that ferroptosis occurring within the osteogenic lineage acts as a catalyst in the progression of periodontitis by stimulating osteoclastogenesis through the secretion of inflammatory cytokines and inhibiting osteoblastic function, providing insights into ferroptosis-induced alterations in microenvironment-based intercellular communication. Ferroptosis is a promising target for controlling inflammation and preventing bone resorption in periodontitis.

Virion-incorporated CD14 enables HIV-1 to bind LPS and initiate TLR4 signaling in immune cells.

HIV-1 has a broad range of nuanced interactions with the immune system, and the incorporation of cellular proteins by nascent virions continues to redefine our understanding of the virus-host relationship. Proteins located at the sites of viral egress can be selectively incorporated into the HIV-1 envelope, imparting new functions and phenotypes onto virions, and impacting viral spread and disease. Using virion capture assays and western blot, we show that HIV-1 can incorporate the myeloid antigen CD14 into its viral envelope. Virion-incorporated CD14 remained biologically active and able to bind its natural ligand, bacterial lipopolysaccharide (LPS), as demonstrated by flow virometry and immunoprecipitation assays. Using a Toll-like receptor 4 (TLR4) reporter cell line, we also demonstrated that virions with bound LPS can trigger TLR4 signaling to activate transcription factors that regulate inflammatory gene expression. Complementary assays with THP-1 monocytes demonstrated enhanced secretion of inflammatory cytokines like tumor necrosis factor alpha (TNF-α) and the C-C chemokine ligand 5 (CCL5), when exposed to LPS-loaded virus. These data highlight a new type of interplay between HIV-1 and the myeloid cell compartment, a previously well-established cellular contributor to HIV-1 pathogenesis and inflammation. Persistent gut inflammation is a hallmark of chronic HIV-1 infection, and contributing to this effect is the translocation of microbes across the gut epithelium. Our data herein provide proof of principle that virion-incorporated CD14 could be a novel mechanism through which HIV-1 can drive chronic inflammation, facilitated by HIV-1 particles binding bacterial LPS and initiating inflammatory signaling in TLR4-expressing cells.IMPORTANCEHIV-1 establishes a lifelong infection accompanied by numerous immunological changes. Inflammation of the gut epithelia, exacerbated by the loss of mucosal T cells and cytokine dysregulation, persists during HIV-1 infection. Feeding back into this loop of inflammation is the translocation of intestinal microbes across the gut epithelia, resulting in the systemic dissemination of bacterial antigens, like lipopolysaccharide (LPS). Our group previously demonstrated that the LPS receptor, CD14, can be readily incorporated by HIV-1 particles, supporting previous clinical observations of viruses derived from patient plasma. We now show that CD14 can be incorporated by several primary HIV-1 isolates and that this virion-incorporated CD14 can remain functional, enabling HIV-1 to bind to LPS. This subsequently allowed CD14+ virions to transfer LPS to monocytic cells, eliciting pro-inflammatory signaling and cytokine secretion. We posit here that virion-incorporated CD14 is a potential contributor to the dysregulated immune responses present in the setting of HIV-1 infection.

DNA Damage Responses in Tumors Are Not Proliferative Stimuli, but Rather They Are DNA Repair Actions Requiring Supportive Medical Care.

In tumors, somatic mutagenesis presumably drives the DNA damage response (DDR) via altered regulatory pathways, increasing genomic instability and proliferative activity. These considerations led to the standard therapeutic strategy against cancer: the disruption of mutation-activated DNA repair pathways of tumors. Justifying that cancer cells are not enemies to be killed, but rather that they are ill human cells which have the remnants of physiologic regulatory pathways. 1. Genomic instability and cancer development may be originated from a flaw in estrogen signaling rather than excessive estrogen signaling; 2. Healthy cells with genomic instability exhibit somatic mutations, helping DNA restitution; 3. Somatic mutations in tumor cells aim for the restoration of DNA damage, rather than further genomic derangement; 4. In tumors, estrogen signaling drives the pathways of DNA stabilization, leading to apoptotic death; 5. In peritumoral cellular infiltration, the genomic damage of the tumor induces inflammatory cytokine secretion and increased estrogen synthesis. In the inflammatory cells, an increased growth factor receptor (GFR) signaling confers the unliganded activation of estrogen receptors (ERs); 6. In breast cancer cells responsive to genotoxic therapy, constitutive mutations help the upregulation of estrogen signaling and consequential apoptosis. In breast tumors non-responsive to genotoxic therapy, the possibilities for ER activation via either liganded or unliganded pathways are exhausted, leading to farther genomic instability and unrestrained proliferation. Understanding the real character and behavior of human tumors at the molecular level suggests that we should learn the genome repairing methods of tumors and follow them by supportive therapy, rather than provoking additional genomic damages.

ITGAM is a critical gene in ischemic stroke.

Globally, ischemic stroke (IS) is ranked as the second most prevailing cause of mortality and is considered lethal to human health. This study aimed to identify genes and pathways involved in the onset and progression of IS. GSE16561 and GSE22255 were downloaded from the Gene Expression Omnibus (GEO) database, merged, and subjected to batch effect removal using the ComBat method. The limma package was employed to identify the differentially expressed genes (DEGs), followed by enrichment analysis and protein-protein interaction (PPI) network construction. Afterward, the cytoHubba plugin was utilized to screen the hub genes. Finally, a ROC curve was generated to investigate the diagnostic value of hub genes. Validation analysis through a series of experiments including qPCR, Western blotting, TUNEL, and flow cytometry was performed. The analysis incorporated 59 IS samples and 44 control samples, revealing 226 DEGs, of which 152 were up-regulated and 74 were down-regulated. These DEGs were revealed to be linked with the inflammatory and immune responses through enrichment analyses. Overall, the ROC analysis revealed the remarkable diagnostic potential of ITGAM and MMP9 for IS. Quantitative assessment of these genes showed significant overexpression in IS patients. ITGAM modulation influenced the secretion of critical inflammatory cytokines, such as IL-1β, IL-6, and TNF-α, and had a distinct impact on neuronal apoptosis. The inflammation and immune response were identified as potential pathological mechanisms of IS by bioinformatics and experiments. In addition, ITGAM may be considered a potential therapeutic target for IS.

Human-induced pluripotent stem cell-derived neural stem cell exosomes improve blood-brain barrier function after intracerebral hemorrhage by activating astrocytes via PI3K/AKT/MCP-1 axis.

JOURNAL/nrgr/04.03/01300535-202502000-00029/figure1/v/2024-05-28T214302Z/r/image-tiff Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor prognosis. Human-induced pluripotent stem cell-derived neural stem cell exosomes (hiPSC-NSC-Exos) have shown potential for brain injury repair in central nervous system diseases. In this study, we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying mechanism. Our results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits, enhanced blood-brain barrier integrity, and reduced leukocyte infiltration in a mouse model of intracerebral hemorrhage. Additionally, hiPSC-NSC-Exos decreased immune cell infiltration, activated astrocytes, and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1, macrophage inflammatory protein-1α, and tumor necrosis factor-α post-intracerebral hemorrhage, thereby improving the inflammatory microenvironment. RNA sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion, thereby improving blood-brain barrier integrity. Treatment with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these effects. In summary, our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity, in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes.

The Role of Copper-Induced M2 Macrophage Polarization in Protecting Cartilage Matrix in Osteoarthritis.

BACKGROUND The pathological mechanism of osteoarthritis is still unclear. The regulation of the immune microenvironment has been of growing interest in the progression and treatment of osteoarthritis. Macrophages with different phenotypes, producing different cytokines, have been linked to the mechanism of cartilage injury in osteoarthritis. Copper ions play a role in the immune response and are involved in the pathological mechanisms of osteoarthritis by affecting the metabolism of the cartilage matrix. Bioactive glass (BG) is an osteogenic material with superior biocompatibility. Here, we report on the regulatory behavior of macrophages using a copper-based composite BG material. MATERIAL AND METHODS Cu-BGC powder was prepared by sol-gel method, and scaffolds were fabricated and characterized using 3D printing. Macrophage cultures grown with Cu-BGC were examined for cell culture and proliferation. The effect of Cu-BGC on the degradation metabolism of chondrocytes, cultured in the environment of inflammatory cytokine IL-1ß, was determined. In addition, the morphology of macrophages, secretion of inflammatory cytokines, and expression of surface markers were examined. RESULTS The results show that Cu-BGC promotes macrophage proliferation at a range of concentrations and increases the secretion of anti-inflammatory cytokines while inhibiting proinflammatory cytokines. At the same time, M2-type cell surface markers are definitely expressed and the morphology of macrophages is altered. In addition, Cu-BGC inhibited the degradation metabolism of chondrocytes in the inflammatory environment induced by IL-1ß. CONCLUSIONS These results suggest that Cu-BGC induced macrophage polarization into an M2 type anti-inflammatory phenotype, and inhibition of immune injury response may play a role in delaying cartilage matrix damage in osteoarthritis.

SLAMF1-derived peptide exhibits cardio protection after permanent left anterior descending artery ligation in mice.

Acute myocardial infarction (MI) results in tissue damage to affected areas of the myocardium. The initial inflammatory response is the most damaging for residual cardiac function, while at later stages inflammation is a prerequisite for proper healing and scar formation. Balancing the extent and duration of inflammation during various stages after MI is thus pivotal for preserving cardiac function. Recently, a signaling lymphocytic activation molecule 1 (SLAMF1)-derived peptide (P7) was shown to reduce the secretion of inflammatory cytokines and protected against acute lipopolysaccharide-induced death in mice. In the present study, we experimentally induced MI by permanent ligation of the left anterior descending artery (LAD) in mice and explored the beneficial effect of immediately administering P7, with the aim of dampening the initial inflammatory phase without compromising the healing and remodeling phase. Blood samples taken 9h post-LAD surgery and P7 administration dampened the secretion of inflammatory cytokines, but this dampening effect of P7 was diminished after 3 days. Echocardiography revealed less deterioration of cardiac contraction in mice receiving P7. In line with this, less myocardial damage was observed histologically in P7-treated mice. In conclusion, the administration of a SLAMF1-derived peptide (P7) immediately after induction of MI reduces the initial myocardial inflammation, reduces infarct expansion, and leads to less deterioration of cardiac contraction.