Netrin-1 and its receptor Unc5b as markers of periodontal disease.

OBJECTIVES: The aim of this present study was to evaluate the levels of Netrin-1 and Unc5b in periodontal health and disease. BACKGROUND: Netrin-1, acting via its receptor UNC5b, regulates the inflammatory response and takes apart in bone destructive diseases. METHODS: Samples of gingival crevicular fluid (GCF), whole saliva, and serum were taken from systemically healthy, nonsmoking 20 periodontitis , 20 gingivitis patients, and 20 periodontally healthy subjects at baseline and 4 weeks after nonsurgical periodontal treatment (NSPT). Whole-mouth and site-specific clinical periodontal parameters were recorded. Netrin-1 and Unc5b levels were measured by enzyme-linked immunosorbent assay. Data were analyzed by nonparametric tests. RESULTS: Total amount of Netrin-1 in GCF was significantly higher in periodontitis than the others, and the levels were significantly reduced after NSPT. Salivary and serum concentrations of Netrin-1 were significantly different among the study groups (P = .000), and NSPT significantly increased the concentration levels of both salivary and serum Netrin-1 (P < .05). Healthy subjects had significantly lower GCF (P = .001) and conversely, higher salivary and serum levels of Unc5b than the other groups (P = .002). The GCF levels of Unc5b were significantly reduced (P < .01), and conversely, serum concentrations were significantly increased after NSPT (P < .05). GCF Netrin-1 and Unc5b total amounts were positively correlated with clinical parameters (P < .01 and P < .05) whereas salivary Netrin-1 and Unc5b concentrations were negatively correlated with clinical parameters (P < .01 and P < .05). CONCLUSIONS: The results of this study indicate that Netrin-1 and its receptor Unc5b may have essential roles in periodontal inflammation and those can be assumed as useful therapeutic agent to control inflammation and periodontal breakdown.

Netrin-1-like-immunoreactivity Coexpresses With DCC and Has a Differential Level in the Myenteric Cholinergic and Nitrergic Neurons of the Adult Mouse Colon.

Netrin-1 is a potent axonal and neuronal guidance cue in the developing nervous system. Netrin-1 functions are mediated by its receptors, such as deleted in colorectal cancer (DCC) present on axons and neurons. Localization of DCC and Netrin-1 on various types of enteric neurons and their role in the mature enteric nervous system is unknown. The results of our study revealed that almost all enteric neurons and processes express DCC and Netrin-1 in the adult mice. Netrin-1-like-immunoreactivity (IR) was detected in the cytoplasm of neurons with some showing strong or weak staining. The majority of Netrin-1-like-immunoreactive enteric neurons were choline acetyltransferase (ChAT)-positive. However, ~19% of neurons were strongly Netrin-1-like-positive but ChAT-negative while ~8% of neurons were Netrin-1-like-negative but strongly ChAT-positive. In contrast, almost all nitric oxide synthase (nNOS)-positive enteric neurons displayed strong Netrin-1-like-IR. This differential intensity of Netrin-1 expression in the myenteric neurons might determine major neuronal subtypes regulating intestinal motility, ChAT-IR excitatory, and nNOS-IR inhibitory muscle motor and interneurons. This is the first study demonstrating the localization of DCC and Netrin-1 in the colonic myenteric plexus of the adult mice and their expression level determining two major neuronal subtypes regulating intestinal motility.

Ultrasound molecular imaging as a non-invasive companion diagnostic for netrin-1 interference therapy in breast cancer.

In ultrasound molecular imaging (USMI), ligand-functionalized microbubbles (MBs) are used to visualize vascular endothelial targets. Netrin-1 is upregulated in 60% of metastatic breast cancers and promotes tumor progression. A novel netrin-1 interference therapy requires the assessment of netrin-1 expression prior to treatment. In this study, we studied netrin-1 as a target for USMI and its potential as a companion diagnostic in breast cancer models. Methods: To verify netrin-1 expression and localization, an in vivo immuno-localization approach was applied, in which anti-netrin-1 antibody was injected into living mice 24 h before tumor collection, and revealed with secondary fluorescent antibody for immunofluorescence analysis. Netrin-1 interactions with the cell surface were studied by flow cytometry. Netrin-1-targeted MBs were prepared using MicroMarker Target-Ready (VisualSonics), and validated in in vitro binding assays in static conditions or in a flow chamber using purified netrin-1 protein or netrin-1-expressing cancer cells. In vivo USMI of netrin-1 was validated in nude mice bearing human netrin-1-positive SKBR7 tumors or weakly netrin-1-expressing MDA-MB-231 tumors using the Vevo 2100 small animal imaging device (VisualSonics). USMI feasibility was further tested in transgenic murine FVB/N Tg(MMTV/PyMT634Mul) (MMTV-PyMT) mammary tumors. Results: Netrin-1 co-localized with endothelial CD31 in netrin-1-positive breast tumors. Netrin-1 binding to the surface of endothelial HUVEC and cancer cells was partially mediated by heparan sulfate proteoglycans. MBs targeted with humanized monoclonal anti-netrin-1 antibody bound to netrin-1-expressing cancer cells in static and dynamic conditions. USMI signal was significantly increased with anti-netrin-1 MBs in human SKBR7 breast tumors and transgenic murine MMTV-PyMT mammary tumors compared to signals recorded with either isotype control MBs or after blocking of netrin-1 with humanized monoclonal anti-netrin-1 antibody. In weakly netrin-1-expressing human tumors and normal mammary glands, no difference in imaging signal was observed with anti-netrin-1- and isotype control MBs. Ex vivo analysis confirmed netrin-1 expression in MMTV-PyMT tumors. Conclusions: These results show that USMI allowed reliable detection of netrin-1 on the endothelium of netrin-1-positive human and murine tumors. Significant differences in USMI signal for netrin-1 reflected the significant differences in netrin-1 mRNA & protein expression observed between different breast tumor models. The imaging approach was non-invasive and safe, and provided the netrin-1 expression status in near real-time. Thus, USMI of netrin-1 has the potential to become a companion diagnostic for the stratification of patients for netrin-1 interference therapy in future clinical trials.

Netrin 1 and Alpha-Methyl Acylcoenzim-A Racemase in diagnosis of prostate cancer.

OBJECTIVES: To investigate serum and urine levels of Alpha-methylacyl-CoA-racemase (AMACR) and Netrin 1 in patients with and without prostate cancer and to determine whether these markers could be used as alternatives in diagnosis of prostate cancer instead of serum prostate specific antigen (PSA) levels. METHODS: One hundred and seventy five patients between 45-75 years to whom transrectal ultrasound guided biopsies were performed for abnormal serum PSA levels or digital rectal examinations were included. The levels of AMACR and Netrin 1 levels of blood and urine samples of 5 mL those were taken prior to biopsies were measured. . RESULTS: The mean age of the patients was 62.7 ±6.4 years. Prostate cancer was detected in 40 patients (22.8%) while 135 of them (77.2%) were diagnosed as benign prostate hyperplasia (BPH). In BPH group, serum and urine levels of AMACR and Netrin 1 were 13.4 ±16.9 ng/mL; 7.1 ±3.4 ng/mL; 164.1±46 pg/mL and 19.5 ±5.0 pg/mL respectively. The levels of serum and urine levels of AMACR and Netrin 1 were 10.2 ±9.8 ng/mL; 6.8 ±2.5 ng/mL; 159.1 ±44.1 pg/mL and 20.1 ±5.3 pg/mL respectively in prostate cancer group. There was no statistically significant difference or correlation between these two groups serum and urine AMACR and Netrin 1 results. CONCLUSIONS: Serum and urine levels of AMACR and Netrin 1 were not found to be alternatives for serum PSA levels in the diagnosis of prostate cancer in this study.

OBJETIVOS: Investigar los niveles de alfa-metil acilcoenzima-A y Netrina 1 en pacientes con y sin cáncer de próstata y determinar si estos marcadores pueden ser usados como una alternativa en el diagnóstico de cáncer de próstata en lugar del antígeno prostático específico en suero (PSA). MÉTODOS: Fueron incluidos 175 pacientes entre 45-75 años, a quienes se les realizó una biopsia de próstata guiada por ultrasonido por presentar un nivel anormal de PSA en el suero o un tacto rectal. Se tomó una muestra de 5 mL de sangre y orina para medir los niveles de alfa-metil acilcoenzima-A y Netrina 1. Estos niveles se midieron antes del análisis de la biopsia. RESULTADOS: La edad media de los pacientes fue de 62.7±6.4 años. Se detectó cander en 40 pacientes (22.8%), mientras que a 135 de ellos (77.2%) se les diagnóstico una hiperplasia benigna de próstata (HBP). En el grupo HBP los niveles en suero y orina de alfa-metil acilcoenzima-A y Netrina 1 fueron 13.4 ±16.9 ng/mL; 7.1 ±3.4 ng/mL; 164.1 ±46 pg/mL y 19.5 ±5.0 pg/mL respectivamente. En el grupo con cáncer de próstata los niveles en suero y orina de alfa-metil acilcoenzima-A y Netrina 1 fueron 10.2 ±9.8 ng/mL; 6.8 ±2.5 ng/mL; 159.1 ±44.1 pg/mL y 20.1 ±5.3 pg/mL respectivamente. No hubo una diferencia significativa o una correlación entre los niveles de alfa-metil acilcoenzima-A y Netrina 1 en suero y orina al comparar estos dos grupos de pacientes. CONCLUSIONES: Los niveles de alfa-metil acilcoenzima-A y Netrina 1 en suero y orina no son una alternativa para reemplazar el PSA en suero para el diagnóstico de cáncer de próstata.

Netrin 1 and Alpha-Methyl Acylcoenzim-A Racemase in diagnosis of prostate cancer / Netrina 1 y Alfa Metil-Acil coenzima-A Racemasa para el diagnóstico de cáncer de próstata

Abstract Objectives: To investigate serum and urine levels of Alpha-methylacyl-CoA-racemase (AMACR) and Netrin 1 in patients with and without prostate cancer and to determine whether these markers could be used as alternatives in diagnosis of prostate cancer instead of serum prostate specific antigen (PSA) levels. Methods: One hundred and seventy five patients between 45-75 years to whom transrectal ultrasound guided biopsies were performed for abnormal serum PSA levels or digital rectal examinations were included. The levels of AMACR and Netrin 1 levels of blood and urine samples of 5 mL those were taken prior to biopsies were measured. . Results: The mean age of the patients was 62.7 ±6.4 years. Prostate cancer was detected in 40 patients (22.8%) while 135 of them (77.2%) were diagnosed as benign prostate hyperplasia (BPH). In BPH group, serum and urine levels of AMACR and Netrin 1 were 13.4 ±16.9 ng/mL; 7.1 ±3.4 ng/mL; 164.1±46 pg/mL and 19.5 ±5.0 pg/mL respectively. The levels of serum and urine levels of AMACR and Netrin 1 were 10.2 ±9.8 ng/mL; 6.8 ±2.5 ng/mL; 159.1 ±44.1 pg/mL and 20.1 ±5.3 pg/mL respectively in prostate cancer group. There was no statistically significant difference or correlation between these two groups serum and urine AMACR and Netrin 1 results Conclusions: Serum and urine levels of AMACR and Netrin 1 were not found to be alternatives for serum PSA levels in the diagnosis of prostate cancer in this study.

Resumen Objetivos: Investigar los niveles de alfa-metil acilcoenzima-A y Netrina 1 en pacientes con y sin cáncer de próstata y determinar si estos marcadores pueden ser usados como una alternativa en el diagnóstico de cáncer de próstata en lugar del antígeno prostático específico en suero (PSA). Métodos: Fueron incluidos 175 pacientes entre 45-75 años, a quienes se les realizó una biopsia de próstata guiada por ultrasonido por presentar un nivel anormal de PSA en el suero o un tacto rectal. Se tomó una muestra de 5 mL de sangre y orina para medir los niveles de alfa-metil acilcoenzima-A y Netrina 1. Estos niveles se midieron antes del análisis de la biopsia. Resultados: La edad media de los pacientes fue de 62.7±6.4 años. Se detectó cander en 40 pacientes (22.8%), mientras que a 135 de ellos (77.2%) se les diagnóstico una hiperplasia benigna de próstata (HBP). En el grupo HBP los niveles en suero y orina de alfa-metil acilcoenzima-A y Netrina 1 fueron 13.4 ±16.9 ng/mL; 7.1 ±3.4 ng/mL; 164.1 ±46 pg/mL y 19.5 ±5.0 pg/mL respectivamente. En el grupo con cáncer de próstata los niveles en suero y orina de alfa-metil acilcoenzima-A y Netrina 1 fueron 10.2 ±9.8 ng/mL; 6.8 ±2.5 ng/mL; 159.1 ±44.1 pg/mL y 20.1 ±5.3 pg/mL respectivamente. No hubo una diferencia significativa o una correlación entre los niveles de alfa-metil acilcoenzima-A y Netrina 1 en suero y orina al comparar estos dos grupos de pacientes. Conclusiones: Los niveles de alfa-metil acilcoenzima-A y Netrina 1 en suero y orina no son una alternativa para reemplazar el PSA en suero para el diagnóstico de cáncer de próstata.

Netrin-1 promotes diabetic corneal wound healing through molecular mechanisms mediated via the adenosine 2B receptor.

Netrins are secreted chemoattractants with the roles in axon guidance, cell migration and epithelial plasticity. In the present study, we investigated the roles of netrin-1 in the regulation of corneal epithelial wound healing, inflammation response and nerve fiber regeneration in diabetic mice and cultured corneal epithelial cells. In diabetic mice, the expression of netrin-1 was decreased when compared with that of normal mice. Furthermore, high glucose blocked the wounding-induced up-regulation of netrin-1 expression in corneal epithelial cells. Exogenous netrin-1 promoted the corneal epithelial wound healing in diabetic mice, and facilitated the proliferation and migration by reactivating the phosphorylation of ERK and EGFR in high-glucose treated corneal epithelial cells. Moreover, netrin-1 decreased the neutrophil infiltration and promoted M2 macrophage transition, accompanied with the attenuated expression of pro-inflammatory factors in diabetic mouse corneal epithelium. The promotions of netrin-1 on corneal epithelial wound healing and inflammation resolution were mediated at least through the adenosine 2B receptor. In addition, netrin-1 promoted the regeneration of corneal nerve fibers that was impaired in diabetic mice. Taken together, netrin-1 regulates corneal epithelial wound healing, inflammation response and nerve fiber regeneration in diabetic mice, indicating the potential application for the therapy of diabetic keratopathy.

Dexmedetomidine Prevents Cognitive Decline by Enhancing Resolution of High Mobility Group Box 1 Protein-induced Inflammation through a Vagomimetic Action in Mice.

BACKGROUND: Inflammation initiated by damage-associated molecular patterns has been implicated for the cognitive decline associated with surgical trauma and serious illness. We determined whether resolution of inflammation mediates dexmedetomidine-induced reduction of damage-associated molecular pattern-induced cognitive decline. METHODS: Cognitive decline (assessed by trace fear conditioning) was induced with high molecular group box 1 protein, a damage-associated molecular pattern, in mice that also received blockers of neural (vagal) and humoral inflammation-resolving pathways. Systemic and neuroinflammation was assessed by proinflammatory cytokines. RESULTS: Damage-associated molecular pattern-induced cognitive decline and inflammation (mean ± SD) was reversed by dexmedetomidine (trace fear conditioning: 58.77 ± 8.69% vs. 41.45 ± 7.64%, P < 0.0001; plasma interleukin [IL]-1ß: 7.0 ± 2.2 pg/ml vs. 49.8 ± 6.0 pg/ml, P < 0.0001; plasma IL-6: 3.2 ± 1.6 pg/ml vs. 19.5 ± 1.7 pg/ml, P < 0.0001; hippocampal IL-1ß: 4.1 ± 3.0 pg/mg vs. 41.6 ± 8.0 pg/mg, P < 0.0001; hippocampal IL-6: 3.4 ± 1.3 pg/mg vs. 16.2 ± 2.7 pg/mg, P < 0.0001). Reversal by dexmedetomidine was prevented by blockade of vagomimetic imidazoline and α7 nicotinic acetylcholine receptors but not by α2 adrenoceptor blockade. Netrin-1, the orchestrator of inflammation-resolution, was upregulated (fold-change) by dexmedetomidine (lung: 1.5 ± 0.1 vs. 0.7 ± 0.1, P < 0.0001; spleen: 1.5 ± 0.2 vs. 0.6 ± 0.2, P < 0.0001), resulting in upregulation of proresolving (lipoxin-A4: 1.7 ± 0.2 vs. 0.9 ± 0.2, P < 0.0001) and downregulation of proinflammatory (leukotriene-B4: 1.0 ± 0.2 vs. 3.0 ± 0.3, P < 0.0001) humoral mediators that was prevented by α7 nicotinic acetylcholine receptor blockade. CONCLUSIONS: Dexmedetomidine resolves inflammation through vagomimetic (neural) and humoral pathways, thereby preventing damage-associated molecular pattern-mediated cognitive decline.