Effect Of Gal-1 Research Articles

NPRL2 promotes TRIM16-mediated ubiquitination degradation of Galectin-3 to prevent CD8+T lymphocyte cuproptosis in glioma

BackgroundOur previous study found that tumor suppressor nitrogen permease regulator like-2(NPRL2) is frequently downregulated in glioma, leading to malignant growth. However, NPRL2-mediated crosstalk between tumor cells and immune cells remains unclear.MethodsThe regulatory effects of NPRL2 on tripartite motif–containing protein 16(TRIM16) dependent ubiquitination degradation of Galectin-3(Gal-3) were explored. The effects of Gal-3 on copper uptake, immunocompetence and cuproptosis were investigated in CD8+T lymphocytes(CD8+T cells). The ability of NPRL2 to protect CD8+T cells from Gal-3 damage was evaluated. Furthermore, the correlations among NPRL2, TRIM16, Gal-3 and CD8+T cell accumulation were analyzed in glioma clinical specimens.ResultsNPRL2 increased the TRIM16 expression via inactivation of ERK1/2, which in turn promoted the ubiquitination-mediated degradation of Gal-3 and diminished Gal-3 release from glioma cells. Moreover, Gal-3 accelerated copper uptake and triggered cuproptosis in CD8+T cells, whereas NPRL2 increased CD8+T cell recruitment and prevented impairment of CD8+T cells by Gal-3. Clinical samples revealed that NPRL2 expression was positively associated with TRIM16 expression and negatively correlated with Gal-3, but Gal-3 expression was negatively associated with CD8+T cell accumulation.ConclusionGlioma-derived NPRL2/TRIM16/Gal-3 axis participates in the regulation of CD8+T cell cuproptosis, which provides a promising strategy to rescue the immune activity of CD8+T cells and reverse immunosuppression in glioma.

The Possible Effects of Galectin-3 on Mechanisms of Renal and Hepatocellular Injury Induced by Intravascular Hemolysis.

Intravascular hemolysis is a central feature of congenital and acquired hemolytic anemias, complement disorders, infectious diseases, and toxemias. Massive and/or chronic hemolysis is followed by the induction of inflammation, very often with severe damage of organs, which enhances the morbidity and mortality of hemolytic diseases. Galectin-3 (Gal-3) is a β-galactoside-binding lectin that modulates the functions of many immune cells, thus affecting inflammatory processes. Gal-3 is also one of the main regulators of fibrosis. The role of Gal-3 in the development of different kidney and liver diseases and the potential of therapeutic Gal-3 inhibition have been demonstrated. Therefore, the objective of this review is to discuss the possible effects of Gal-3 on the process of kidney and liver damage induced by intravascular hemolysis, as well as to shed light on the potential therapeutic targeting of Gal-3 in intravascular hemolysis.

Regulation of Nrf2/Keap1 signaling pathway in cancer drug resistance by galectin-1: cellular and molecular implications.

Oxidative stress is characterized by the deregulation of the redox state in the cells, which plays a role in the initiation of various types of cancers. The activity of galectin-1 (Gal-1) depends on the cell redox state and the redox state of the microenvironment. Gal-1 expression has been related to many different tumor types, as it plays important roles in several processes involved in cancer progression, such as apoptosis, cell migration, adhesion, and immune response. The erythroid-2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1) signaling pathway is a crucial mechanism involved in both cell survival and cell defense against oxidative stress. In this review, we delve into the cellular and molecular roles played by Gal-1 in the context of oxidative stress onset in cancer cells, particularly focusing on its involvement in activating the Nrf2/Keap1 signaling pathway. The emerging evidence concerning the anti-apoptotic effect of Gal-1, together with its ability to sustain the activation of the Nrf2 pathway in counteracting oxidative stress, supports the role of Gal-1 in the promotion of tumor cells proliferation, immuno-suppression, and anti-tumor drug resistance, thus highlighting that the inhibition of Gal-1 emerges as a potential strategy for the restraint and regression of tumor progression. Overall, a deeper understanding of the multi-functionality and disease-specific expression profiling of Gal-1 will be crucial for the design and development of novel Gal-1 inhibitors as anticancer agents. Excitingly, although it is still understudied, the ever-growing knowledge of the sophisticated interplay between Gal-1 and Nrf2/Keap1 will enable researchers to gain valuable insights into the underlying causes of carcinogenesis and metastasis.

Resistance to anti-PD-1/anti-PD-L1: galectin-3 inhibition with GB1211 reverses galectin-3-induced blockade of pembrolizumab and atezolizumab binding to PD-1/PD-L1.

Galectin-3 (Gal-3) is a β-galactoside-binding lectin that is highly expressed within the tumor microenvironment of aggressive cancers and has been suggested to predict a poor response to immune checkpoint therapy with the anti-PD-1 monoclonal antibody pembrolizumab. We aimed to assess if the effect of Gal-3 was a result of direct interaction with the immune checkpoint receptor. The ability of Gal-3 to interact with the PD-1/PD-L1 complex in the absence and presence of blocking antibodies was assessed in in vitro biochemical and cellular assays as well as in an in vivo syngeneic mouse cancer model. Gal-3 reduced the binding of the checkpoint inhibitors pembrolizumab (anti-PD-1) and atezolizumab (anti-PD-L1), by potentiating the interaction between the PD-1/PD-L1 complex. In the presence of a highly selective Gal-3 small molecule inhibitor (GB1211) the binding of the anti-PD-1/anti-PD-L1 therapeutics was restored to control levels. This was observed in both a surface plasmon resonance assay measuring protein-protein interactions and via flow cytometry. Combination therapy with GB1211 and an anti-PD-L1 blocking antibody reduced tumor growth in an in vivo syngeneic model and increased the percentage of tumor infiltrating T lymphocytes. Our study suggests that Gal-3 can potentiate the PD-1/PD-L1 immune axis and potentially contribute to the immunosuppressive signalling mechanisms within the tumor microenvironment. In addition, Gal-3 prevents atezolizumab and pembrolizumab target engagement with their respective immune checkpoint receptors. Reversal of this effect with the clinical candidate GB1211 offers a potential enhancing combination therapeutic with anti-PD-1 and -PD-L1 blocking antibodies.

Galectin-3 interacts with PD-1 and counteracts the PD-1 pathway-driven regulation of T cell and osteoclast activity in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation and bone erosions. The glycosylated programmed death-1 (PD-1) receptor plays an important role in regulating immune responses and maintaining tolerance. In this study, we focus on two features observed in RA: impaired PD-1 signalling and Galectin-3 (Gal-3) upregulation. We hypothesize that Gal-3 binds PD-1 and PD-1 ligands, potentially contributing to impaired PD-1 signalling. PD-1 and Gal-3 levels in RA synovial fluid (SF) and plasma were evaluated by ELISA. PD-1 and Gal-3 interaction was examined by Surface Plasmon Resonance and ELISA. PD-1, PD-L1 and Gal-3 expression on mononuclear cells from SF and peripheral blood as well as fibroblast-like synoviocytes were examined by flow cytometry. Effects of Gal-3 and PD-L1 on osteoclast formation was evaluated by tartrate-resistant acid phosphatase assay. We show that Gal-3 binds PD-1 and PD-L1. Results demonstrated high expression of PD-1 and Gal-3 on mononuclear cells, especially from SF. Gal-3 inhibited PD-1 signalling when PD-L1 was present. Furthermore, a role of Gal-3 in osteoclast formation was observed in vitro, both directly but also through PD-1:PD-L1 inhibition. Effects of Gal-3 on the PD-1 signalling axis are proposed to be inhibitory, meaning high Gal-3 levels in the complex synovial microenvironment are not desirable in RA. Preventing Gal-3's inhibitory role on PD-1 signalling could, therefore, be a therapeutic target in RA by affecting inflammatory T cell responses and osteoclasts.

Galectin-1 deletion in mice causes bone loss via impaired osteogenic differentiation potential of BMSCs.

Bone formation is dependent on the osteoblasts which are differentiated from bone marrow stromal cells (BMSCs). In addition to potent proliferation, self-renewal, and pluripotent differentiation, BMSCs have been extensively studied due to their low immunogenicity and immunomodulatory effects. Recently, galectin-1 (Gal-1) has been proposed as a potent mediator of immunomodulatory properties of BMSCs. Previous study demonstrated that Gal-1 showed age-related decline in mice serum and serum Gal-1 was positively associated with bone mass in mice. The current study makes attempts to elucidate the functional role of Gal-1 in skeletal system by investigating the regulation of Gal-1 expression during BMSCs osteogenic differentiation and the molecular mechanisms underlying the effects of Gal-1 on BMSCs osteogenic differentiation. In Gal-1 null (-/-) mice, bone loss was observed due to bone formation attenuation. In in vitro experiments, Gal-1 supported the osteogenic differentiation of BMSCs by binding to CD146 to activate Lrp5 expression and Wnt/β-catenin signaling pathway. Meanwhile, there was positive feedback regulation via Wnt/β-catenin signaling to maintain Gal-1 high-level expression during osteogenic differentiation of BMSCs. More importantly, Gal-1 down-regulation in BMSCs and attenuation of osteogenic differentiation potential of BMSCs were observed in aged mice compared with young mice. Gal-1 over-expression could enhance osteogenic differentiation potential of aged BMSCs. Our study will benefit not only for deeper insights into the functional role of Gal-1 but also for finding new targets to modulate BMSCs osteogenic differentiation.

Expression Pattern and Immunoregulatory Roles of Galectin-1 and Galectin-3 in Atopic Dermatitis and Psoriasis.

The pathogenesis of atopic dermatitis (AD) and psoriasis (Ps) overlaps, particularly the activation of the immune response and tissue damage. Here, we evaluated galectin (Gal)-1 and Gal-3 levels, which are beta-galactoside-binding proteins with immunomodulatory functions and examined their effects on human keratinocytes stimulated with either interleukin (IL)-4 or IL-17A. Skin biopsies from AD, Ps, and control patients were evaluated using histological and immunohistochemical analyses. Six studies containing publicly available transcriptome data were individually analyzed using the GEO2R tool to detect Gal-1 and Gal-3 mRNA levels. In vitro, IL-4- or IL-17A-stimulated keratinocytes were treated with or without Gal-1 or Gal-3 to evaluate cytokine release and migration. Our findings showed different patterns of expression for Gal-1 and Gal-3 in AD and Ps skins. Densitometric analysis in skin samples showed a marked increase in the protein Gal-1 levels in Ps epidermis and in both AD and Ps dermis compared to controls. Protein and mRNA Gal-3 levels were downregulated in AD and Ps lesional skin compared with the control samples. In vitro, both galectins addition abrogated the release of IL-8 and RANTES in IL-17-stimulated keratinocytes after 24h, whereas IL-6 release was downregulated by Gal-3 and Gal-1 in IL-4- and IL-17-stimulated cells, respectively. Administration of both galectins also increased the rate of keratinocyte migration under IL-4 or IL-17 stimulation conditions compared with untreated cells. Altogether, the immunoregulatory and migration effects of Gal-1 and Gal-3 on keratinocytes under inflammatory microenvironment make them interesting targets for future therapies in cutaneous diseases.

The neuroprotective effects of Galectin-1 on Parkinson's Disease via regulation of Nrf2 expression.

Parkinson's disease (PD) is one of the neurodegenerative diseases. Galectin-1 (Gal-1) is expressed in the central nervous system. Our study sought to explore the neuroprotective effect of Gal-1 in 1‑methyl‑4‑phenyl pyridine ion (MPP+)-induced cytotoxicity on SH-SY5Y cells. SH-SY5Y cells were cultured in vitro, pretreated with Gal-1, and then exposed to MPP+. Thereafter, the generation of reactive oxygen species (ROS) in SH-SY5Y cells was investigated. The effects of Gal-1 on DNA breakage, cell damage (release of lactate dehydrogenase (LDH)), viability, and apoptosis in SH-SY5Y cells were examined by comet assay, LDH assay, WST-1 assay, and flow cytometry, respectively. Additionally, the regulatory effect of Gal-1 on Nrf2 expression was examined by western blot. Zebrafish embryos were pretreated with Gal-1 and then exposed to MPP+. The locomotor ability of zebrafish larvae was then investigated. MPP+ induced the production of ROS in cells, which can be alleviated by pretreatment with Gal-1. Gal-1 protected cells from MPP+-induced cytotoxicity by preventing DNA breakage and cell injury. Gal-1 inhibited apoptosis in SH-SY5Y cells. The neuroprotective effect of Gal-1 could be abolished when Nrf2 expression knockdown. Moreover, exposure to MPP+ decreased the locomotor activity of zebrafish, which was attenuated by pretreatment with Gal-1. Our study demonstrated that the administration of Gal-1 could protect neurons from cellular stress by preventing apoptosis and eliminating ROS. Moreover, the neuroprotective effect of Gal-1 in neuronal cells could be related to the activation of Nrf2 expression. Therefore, Gal-1 could be a promising strategy for treating PD.

Galectin‑1 alleviates myocardial ischemia‑reperfusion injury by reducing the inflammation and apoptosis of cardiomyocytes

Myocardial ischemia-reperfusion injury (MIRI) is one of the leading causes of morbidity and mortality worldwide, for which there is no effective treatment. The present study aimed to assess novel methods of clinical MIRI treatment by studying the effects of galectin-1 (Gal-1) on MIRI. Male 2-month-old Sprague Dawley rats and the rat cardiomyocyte cell line H9c2 were utilized in the present study. A rat model of MIRI was constructed by ligating the left anterior descending coronary artery, which was subsequently treated with Gal-1. Differences in myocardial injury were then assessed by hematoxylin and eosin (H&E) staining. In addition, the levels of inflammation and apoptosis in rat myocardial tissue were determined by immunohistochemistry staining. Hypoxia-reoxygenation was used to construct a model of MIRI in H9c2 cells. The effect of Gal-1 on the apoptosis and viability of H9c2 cells was also verified by flow cytometry and a Cell Counting Kit-8 assay. The results of H&E staining revealed that Gal-1 alleviated MIRI. Echocardiography demonstrated that Gal-1 improved cardiac function in rats following MIRI. In addition, MIRI increased levels of inflammation and apoptosis in rat myocardial tissues, with Gal-1 treatment reversing this effect. In cellular experiments, Gal-1 served anti-inflammatory and anti-apoptotic effects in hypoxic/reoxygenated cardiomyocytes. In conclusion, Gal-1 served a significant protective effect on the myocardial tissue after ischemia-reperfusion by reducing the level of inflammation and apoptosis in cardiomyocytes.

Soluble CD146 is increased in preeclampsia and interacts with galectin-1 to regulate trophoblast migration through VEGFR2 receptor

To explore the regulatory role of soluble CD146 (sCD146) and its interaction with galectin-1 (Gal1) in placenta-mediated complications of pregnancy. Prospective pilot and experimental studies. University-affiliated hospital and academic research laboratory. One hundred fifteen women divided into three groups: 30 healthy, nonpregnant women, 50 women with normal pregnancies, and 35 with placenta-mediated pregnancy complications. Wound-healing experiments were conducted to study trophoblast migration. Quantification of sCD146 and Gal1 by enzyme-linked immunosorbent assay. Analysis of trophoblast migration by wound closure. Concomitant detection of sCD146 and Gal1 showed lower sCD146 and higher Gal1 concentrations in women with normal pregnancies compared with nonpregnant women. In addition, follow-up of these women revealed a decrease in sCD146 associated with an increase in Gal1 throughout pregnancy. In contrast, in women with preeclampsia, we found significantly higher sCD146 concentrations compared with women with normal pregnancies and no modification of Gal1. We emphasize the opposing effects of sCD146 and Gal, since, unlike Gal1, sCD146 inhibits trophoblast migration. Moreover, the migratory effect of Gal1 was abrogated with the use of an anti-CD146 blocking antibody or the use of small interfering RNA to silence VEGFR2 expression. This suggests that trophoblast migration is mediated though the interaction of Gal1 with CD146, further activating the VEGFR2 signaling pathway. Significantly, sCD146 blocked the migratory effects of Gal1 on trophoblasts and inhibited its secretion, suggesting that sCD146 acts as a ligand trap. Soluble CD146 could be proposed as a biomarker in preeclampsia and a potential therapeutic target. NCT01736826.

The Role of Galectin-3 in 1α,25(OH)2D3-Regulated Osteoclast Formation from White Leghorn Chickens In Vitro.

Bones play an important role in maintaining the level of calcium in blood. They provide support for soft tissues and hematopoiesis and undergo continuous renewal throughout life. In addition, vitamin D is involved in regulating bone and calcium homeostasis. Galectin-3 (Gal-3) is a β-galactoside-binding protein that can regulate bone cell differentiation and function. Here, we aimed to study the regulatory effects of Gal-3 on vitamin-D-regulated osteoclastogenesis and bone resorption in chicken. Gal-3 expression in bone marrow stromal cells (BMSCs) from 18-day-old chicken embryos was inhibited or overexpressed. BMSCs were then co-cultured with bone marrow monocytes/macrophages (BMMs) with or without addition of 1α,25(OH)2D3. The results showed that 1α,25(OH)2D3 upregulated the expression of Gal-3 mRNA and receptor activator of nuclear-factor κB ligand (RANKL) expression in BMSCs and promoted osteoclastogenesis, as shown by the upregulated expression of osteoclast (OC) markers (CtsK, CAII, MMP-9, and TRAP) and increased bone resorption, a method for measuring the bone resorption area in vitro. Knockdown of Gal-3 by small-interfering RNA (siRNA) in BMSCs downregulated the expression of RANKL mRNA and attenuated the effects of 1α,25(OH)2D3 on osteoclastogenesis and bone resorption. Conversely, overexpression of Gal-3 in BMSCs enhanced the effects of osteoclastogenesis and bone resorption by increasing the expression of RANKL mRNA. These results demonstrated that Gal-3 mediates the differentiation and bone resorption of osteoclasts regulated by 1α,25(OH)2D3.

Elevated serum galectin-1 concentrations are associated with increased risks of mortality and acute kidney injury in critically ill patients.

BackgroundGalectin-1 (Gal-1), a member of the β-galactoside binding protein family, is associated with inflammation and chronic kidney disease. However, the effect of Gal-1 on mortality and acute kidney injury (AKI) in critically-ill patients remain unclear.MethodsFrom May 2018 to March 2020, 350 patients admitted to the medical intensive care unit (ICU) of Taipei Veterans General Hospital, a tertiary medical center, were enrolled in this study. Forty-one patients receiving long-term renal replacement therapy were excluded. Serum Gal-1 levels were determined within 24 h of ICU admission. The patients were divided into tertiles according to their serum Gal-1 levels (low, serum Gal-1 < 39 ng/ml; median, 39–70 ng/ml; high, ≥71 ng/ml). All patients were followed for 90 days or until death.ResultsMortality in the ICU and at 90 days was greater among patients with elevated serum Gal-1 levels. In analyses adjusted for the body mass index, malignancy, sepsis, Sequential Organ Failure Assessment (SOFA) score, and serum lactate level, the serum Gal-1 level remained an independent predictor of 90-day mortality [median vs. low: adjusted hazard ratio (aHR) 2.11, 95% confidence interval (CI) 1.24–3.60, p = 0.006; high vs. low: aHR 3.21, 95% CI 1.90–5.42, p < 0.001]. Higher serum Gal-1 levels were also associated with a higher incidence of AKI within 48 h after ICU admission, independent of the SOFA score and renal function (median vs. low: aHR 2.77, 95% CI 1.21–6.34, p = 0.016; high vs. low: aHR 2.88, 95% CI 1.20–6.88, p = 0.017). The results were consistent among different subgroups with high and low Gal-1 levels.ConclusionSerum Gal-1 elevation at the time of ICU admission were associated with an increased risk of mortality at 90 days, and an increased incidence of AKI within 48 h after ICU admission.

Abstract 2685: Tumor hypoxia drives immunosuppression via upregulation of galectin-1 in recurrent Glioblastoma

Abstract Background: Glioblastoma (GB) recurrence is associated with a highly immunosuppressive tumor microenvironment. Previous research in our lab has illustrated that the carbohydrate-binding protein Galectin-1 (Gal-1) has high expression in GB patient samples and plays vital pro-tumorigenic roles within the tumor microenvironment, regulated by hypoxia-inducible factor-1 (HIF-1). However, since Gal-1 displays many different activities by binding to a number of diverse N- or O-glycan modified target proteins, it has been difficult to fully understand how Gal–1 supports tumor growth and promotes resistance to anti-VEGF mAb. Thus, our aim is to elucidate the role of tumor hypoxia which may in turn increase tumor aggressiveness by up-regulating the expression of Gal-1 in relevant GB in vitro and in vivo model. Methods and Results: GB cells were cultured in a hypoxic environment simulated by cobalt chloride (CoCl2), which is a chemical inducer of hypoxia-inducible factor-1α (HIF-1α). HIF-1α is a transcription factor that has an important role in tumor cell adaptation to hypoxia and controls the expression of several genes. Various CoCl2 concentrations were used to simulate degrees of hypoxia in GB cells. Following treatment with 250 µM CoCl2, an MTT assay was conducted to determine the growth and anti-VEGF mAb (+/- Radiation + Temozolomide) sensitivity of GB cells. We observed that CoCl2(chemical activator of HIF-1α)-treatment simulated hypoxia and induced resistance to anti-VEGF mAb treatment via upregulation of HIF-1α, MDR1/P-gp and MRP protein levels. In addition, proapoptotic members of the Bcl-2 protein family, Bax and Bad, were downregulated. The anti-apoptotic member Bcl-2 exhibited no significant change in expression, whereas the ratio of Bcl-2/Bax was increased. We observed that hypoxia induced Gal-1 through mechanisms that are independent of HIF 1α and HIF-2α but involved reactive oxygen species-dependent activation of the transcription factor nuclear factor κB. Since upregulation of hypoxia inducible transcription factors (HIFs) via Gal-1 is the primary adaptive cellular response to a hypoxic environment, we analyzed the effects of Gal-1 inhibition treatment in vivo. We observed significant alteration of hypoxic tumor microenvironment (TME) in recurrent GB by alteration of tumor associate microglia phenotypes from M2 to. M1, suppression of CD4+CD25+Foxp3+ regulatory T cells and activation of CD 8+ T cells in in vivo GB models. Conclusion: The present study revealed that a CoCl2-simulated hypoxic microenvironment was able to effectively induce resistance to anti-VEGF mAb treatment in GB cells. The results demonstrate the inhibitory effect of Gal-1 in the tumor hypoxia microenvironment and inhibition may be a viable therapeutic target for recurrent GB treatment. Citation Format: Wayne Glore, Arabinda Das, Scott M. Lindhorst, Abhay K. Varma, William A. Vandergrift, Sunil J. Patel, David Cachia. Tumor hypoxia drives immunosuppression via upregulation of galectin-1 in recurrent Glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2685.

Galectin-1 Inhibited LPS-Induced Autophagy and Apoptosis of Human Periodontal Ligament Stem Cells.

Periodontitis is a widespread human chronic inflammatory disease of the tooth-surrounding tissues, which induces the destruction of periodontium and pathologic loss of teeth among adults. It has been reported that interleukin (IL)-17 was significantly increased in periodontitis patients compared to controls, while galectin-1 (Gal-1) was lower. Interestingly, it is found that Gal-1 treatment reduced systemic IL-17 levels. Hence, the aim of the present study was to explore the effect of Gal-1 on periodontitis development and investigate its underlying mechanism. In this study, Gal-1 was poorly expressed in lipopolysaccharide (LPS)-induced human periodontal ligament stem cells (hPDLSCs), and Gal-1 overexpression attenuated the production of inflammatory cytokines induced by LPS. Moreover, Gal-1 overexpression alleviated LPS-induced cell autophagy and apoptosis and reduced the expressions of IL-17A and IL-17R. Interestingly, IL-17A reversed the effect of Gal-1 on cell autophagy, inflammation, and cell apoptosis induced by the LPS challenge. In conclusion, Gal-1 inhibited LPS-induced autophagy and apoptosis of hPDLSC via regulation of IL-17A expression. Therefore, Gal-1 may have promising potential in regenerating periodontium.

Galectin-3 predicts cardiovascular events in patients with type-2 diabetes

Abstract Introduction Type-2 diabetes mellitus (T2DM) is associated with early and severe atherosclerosis. However, few biomarkers can predict cardiovascular events in this population. Methods We followed 964 patients with coronary artery disease (CAD), assessing at baseline galectin-3, monocyte chemoattractant protein-1 (MCP-1) and N-terminal fragment of brain natriuretic peptide (NT-proBNP) plasma levels. Secondary outcomes were acute ischemia and heart failure or death. Primary outcome was the combination of the secondary outcomes. Results Male patients were 75.0% in T2DM and 76.6% in the non-T2DM subgroup (p=0.609). Age was 61.0 (54–72) and 60.0 (51–71) years, respectively (p=0.092). 232 patients had T2DM. Patients with T2DM showed higher MCP-1 [144 (113–195) vs. 133 (105–173) pg/ml, p=0.006] and galectin-3 [8.3 (6.5–10.5) vs. 7.8 (5.9–9.8) ng/ml, p=0.049] levels. Median follow-up was 5.39 years (2.81- 6.92). Galectin-3 levels were associated with increased risk of the primary outcome in T2DM patients [HR 1.57 (1.07–2.30); p=0.022], along with a history of cerebrovascular events. Treatment with clopidogrel was associated with lower risk. In contrast, NT-proBNP and MCP-1, but not galectin-3, were related to increased risk of the event in non-diabetic patients [HR 1.21 (1.04–1.42); p=0.017 and HR 1.23 (1.05–1.44); p=0.012, respectively], along with male sex and age. Galectin-3 was also the only biomarker that predicted the development of acute ischemic events and heart failure or death in T2DM patients, while in non-diabetics MCP-1 and NT-proBNP, respectively, predicted these events. Conclusion In CAD patients, cardiovascular events are predicted by galectin-3 plasma levels in patients with T2DM, and by MCP-1 and NT-proBNP in those without T2DM. Effect of Gal-3 on the primary endpoint Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Insituto de Salud Carlos III

Effects of galectin-1 on immunomodulatory properties of human monocyte-derived dendritic cells

Our study aimed to evaluate the effects of Gal-1 in dose depending manner on maturation and immunomodulatory properties of monocyte-derived (Mo) DCs in-vitro. The effects were analyzed by monitoring their phenotypic characteristics, cytokine profile, and the ability to direct the immune response in the co-culture with allogeneic CD4+T cells. Gal-1 reduced the expression of CD80 and CD86 molecules on MoDCs compared to untreated MoDCs. Gal-1 at concentrations of 1 and 6 μg/mL significantly reduced IL-12 production, while the concentration of 3 μg/mL led to its significant increase. Gal-1 in all concentrations induced a significant increase in the production of IL-10. Treatment of MoDCs with 3 and 6 μg/mL of Gal-1 stimulated the production of IL-2 and IFN-γ in the co-culture with CD4+T lymphocytes. This study demonstrated a dual immunomodulatory effect of Gal-1 on MoDCs in terms of immune stimulation and immune suppression, depending on the applied concentration.

Galectin-1 inhibits PDGF-BB-induced proliferation and migration of airway smooth muscle cells through the inactivation of PI3K/Akt signaling pathway.

Childhood asthma is one of the most common chronic childhood diseases. Platelet-derived growth factor BB (PDGF-BB) induced airway smooth muscle cell (ASMC) proliferation and migration are involved in the pathogenesis of asthma. Galectin-1 (Gal-1) is a glycan-binding protein that has been found to be involved in the progression of asthma. However, the mechanism remains unclear. In the current study, we aimed to evaluate the role of Gal-1 in regulating the phenotype switching of ASMCs, which is an important mechanism in the pathogenesis of asthma. Our results showed that Gal-1 was markedly down-regulated in the samples from asthma patients. In vitro study also proved that Gal-1 expression was decreased in PDGF-BB-stimulated ASMCs. In addition, Gal-1 overexpression significantly inhibited PDGF-BB-induced ASMCs proliferation and migration, while Gal-1 knockdown exhibits opposite effects of Gal-1 overexpression. The PDGF-BB-caused reductions in expressions of α-smooth muscle actin (α-SMA), specific muscle myosin heavy chain (SM-MHC), and calponin were elevated by Gal-1 overexpression, but were deteriorated by Gal-1 knockdown in ASMCs. Furthermore, overexpression of Gal-1 inhibited PDGF-BB-stimulated PI3K/Akt activation in ASMCs. Notably, treatment with IGF-1, an activator of PI3K, reversed the effects of Gal-1 on ASMCs proliferation, migration, and phenotype switching. In conclusion, these findings showed that Gal-1 exerted inhibitory effects on PDGF-BB-stimulated proliferation, migration, and phenotype switching of ASMCs via inhibiting the PI3K/Akt signaling pathway. Thus, Gal-1 might be a promising target for the treatment of asthma.

Galectin-1 ameliorates lipopolysaccharide-induced acute lung injury via AMPK-Nrf2 pathway in mice

Inflammation and oxidative stress contribute to the progression of acute lung injury (ALI). Galectin-1 (Gal-1) has important anti-inflammatory properties in renal ischemia-reperfusion injury, arthritis, uveitis, and hepatitis. However, whether Gal-1 could protect against ALI is still poorly elucidated. The current study aimed to investigate the protective effects of Gal-1 against lipopolysaccharide (LPS)-induced ALI and the underlying mechanisms. Accordingly, we found that pretreatment with Gal-1 attenuated the lung tissue injury induced by LPS, with the recovery of lung function, protecting against the production of pro-inflammatory cytokines and oxidative stress. We also confirmed the therapeutic potential of Gal-1 on the survival rate of LPS-challenged mice. In vitro studies demonstrated the protective effects of exogenous Gal-1 through downregulating pro-inflammatory cytokines release and oxidative stress in primary macrophages challenged by LPS. In addition, Gal-1 suppressed TXNIP-NLRP3 inflammasome activation in ALI mice and LPS-treated primary macrophages partly through directly binding to the NLRP3 protein. Gal-1 alleviated LPS-induced lung injury via activation of Nrf-2, which may be associated with AMPK phosphorylation. Collectively, our experimental results firstly provided the support that Gal-1 effectively protected against LPS-induced ALI via suppression of inflammation response and oxidative stress, which were largely dependent on the upregulation of the Nrf2 pathway via phosphorylation of AMPK. These results suggest that Gal-1 could be a valuable therapeutic candidate in the treatment of ALI.

Galectin-1 modulation of neutrophil reactive oxygen species production depends on the cell activation state

Here we report the effects of exogenous and endogenous galectin-1 (Gal-1) in modulating the functional responses of human and murine neutrophils at different stages of activation, i.e. naive, primed, and activated. Exposure to Gal-1 did not induce ROS production in either naive or N-formyl-methionyl-leucyl-phenylalanine-primed (fMLP; 10−9 M) neutrophils. However, Gal-1 elicited a concentration-dependent ROS production in neutrophils activated with fMLP at concentrations ranging from 10-8 M to 10-6 M. Additional fMLP (10-7 M) stimulation of fMLP-activated neutrophils increased ROS production, whose intensity was inversely related to the fMLP concentration used in the first activation step (10-8 M to 10-6 M), and was not influenced by the presence of Gal-1. Naive neutrophils treated with Gal-1 and then exposed to fMLP (10-6 M) or phorbol-12-myristate-13-acetate (10-7 M) produced less ROS, as compared to naive neutrophils not treated with Gal-1. Interestingly, these in vitro Gal-1 effects were associated with Gal-1 carbohydrate-binding activity and the ability to decrease FPR-1 (formyl peptide receptor 1) expression in naive human neutrophils. Conversely, positive ROS modulation by Gal-1 in activated neutrophils was not associated with FPR-1 expression but it was related to its carbohydrate recognition. In vitro, fMLP stimulation of Gal-1-/- mouse neutrophils produced more ROS than fMLP stimulation of Gal-1+/+ neutrophils and this effect may be associated with increased FPR-1 expression. Exogenous Gal-1 induced ROS production in Gal-1-/- mouse neutrophils more effectively than in Gal-1+/+ mouse neutrophils. Compared to Gal-1+/+ mice, Gal-1-/- mice exhibited lower bacterial load in the peritoneal fluid and peripheral blood, thus indicating a greater bactericidal activity in vivo. These findings demonstrate that endogenous Gal-1 restricts ROS generation that correlates with bacterial killing capacity in inflammatory neutrophils. Thus, endogenous and exogenous Gal-1 may either positively or negatively modulate the effector functions of neutrophils according to the cell activation stage.

Altered Cell Surface N-Glycosylation of Resting and Activated T Cells in Systemic Lupus Erythematosus.

Altered cell surface glycosylation in congenital and acquired diseases has been shown to affect cell differentiation and cellular responses to external signals. Hence, it may have an important role in immune regulation; however, T cell surface glycosylation has not been studied in systemic lupus erythematosus (SLE), a prototype of autoimmune diseases. Analysis of the glycosylation of T cells from patients suffering from SLE was performed by lectin-binding assay, flow cytometry, and quantitative real-time PCR. The results showed that resting SLE T cells presented an activated-like phenotype in terms of their glycosylation pattern. Additionally, activated SLE T cells bound significantly less galectin-1 (Gal-1), an important immunoregulatory lectin, while other lectins bound similarly to the controls. Differential lectin binding, specifically Gal-1, to SLE T cells was explained by the increased gene expression ratio of sialyltransferases and neuraminidase 1 (NEU1), particularly by elevated ST6 beta-galactosamide alpha-2,6-sialyltranferase 1 (ST6GAL1)/NEU1 and ST3 beta-galactoside alpha-2,3-sialyltransferase 6 (ST3GAL6)/NEU1 ratios. These findings indicated an increased terminal sialylation. Indeed, neuraminidase treatment of cells resulted in the increase of Gal-1 binding. Altered T cell surface glycosylation may predispose the cells to resistance to the immunoregulatory effects of Gal-1, and may thus contribute to the pathomechanism of SLE.