Mast Cell-Specific Expression of Human Siglec-8 in Conditional Knock-in Mice

Cuproptosis Cell Death Molecular Events and Pathways to Liver Disease

Chronic liver disease ranks as the 11th leading cause of death worldwide, while hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related mortality, representing a substantial risk to public health. Over the past few decades, the global landscape of chronic liver diseases, including hepatitis, metabolic dysfunction-associated steatotic liver disease (MASLD), liver fibrosis, and HCC, has undergone substantial changes. Copper, a vital trace element for human health, is predominantly regulated by the liver. Both copper deficiency and excess can lead to cellular damage and liver dysfunction. Copper deposition is a genetic process of copper-dependent cell death associated with mitochondrial respiration, which is associated with cardiovascular disease and IBD. However, the roles of copper overload and cuproptosis in liver disease remain largely underexplored. This article examines recent studies on copper metabolism and cuproptosis in chronic liver disease, investigating the potential of targeting copper ions as a therapeutic approach. The objective is to offer insights and guidance for future investigations in this developing field of study.

Genome-wide profiling of long non-coding RNA following ozone exposure: A randomized, controlled exposure trial

BACKGROUND

Exposure to ambient ozone has been associated with extrapulmonary health, but the underlying mechanisms remain to be understood. LncRNAs are involved in the regulation of gene expression, but their regulatory mechanisms in ozone-related health effects are scarcely explored.

OBJECTIVE

To investigate genome-wide lncRNA changes after short-term ozone exposure and their regulatory roles in ozone exposure and gene expression.

METHOD

We conducted a randomized, crossover, controlled exposure trial in 32 healthy college students in Shanghai, China. Each participant received both 200-ppb ozone exposure and filtered air exposure for 2 h in a random order with a 14-day washout period. Blood samples were collected after each exposure and used for lncRNA sequencing. Differentially expressed lncRNAs between the two exposures were identified using orthogonal partial least squares discriminant analysis and linear regression analysis. LncRNAs-targeted mRNAs were mapped and subjected to enrichment analyses. We also constructed lncRNA-miRNA-mRNA networks.

RESULTS

A total of 90 lncRNAs were differentially expressed after exposure to ozone, with 49 up-regulated and 41 down-regulated. Enrichment analyses suggested that these dysregulated lncRNAs were involved in a variety of biological processes, including those related to oxidative stress, inflammation response, and cell proliferation, development, and differentiation. Multiple pathways such as IL-17 signaling, NF-kB signaling, and Rho GTPases signaling were also enriched. Furthermore, the lncRNA-miRNA-mRNA network revealed that specific lncRNAs may regulate the expression of inflammation- and angiogenesis-related genes by interacting with miRNAs, such as NEAT1/hsa-miR-500a-3p/SIGLEC8, NEAT1/hsa-miR-6835-3p/SLC16A14, OIP5-AS1/miR-183-5p/EGR1, and SNHG25/hsa-miR-663a/FOSB axes.

CONCLUSION

This study characterized a thorough profile of human lncRNAs following short-term ozone exposure and suggested the regulatory roles of these lncRNAs in ozone-induced inflammatory responses and angiogenesis, providing novel epigenetic insights into the mechanisms of the health effects of ozone exposure.

Adipose-derived stem cells ameliorate radiation-induced lung injury by activating the DDAH1/ADMA/eNOS signaling pathway

Background

Ionizing radiation-induced lung injury is caused by the initial inflammatory reaction and leads to advanced fibrosis of lung tissue. Adipose-derived stem cells (ASCs) are a type of mesenchymal stem cell that can differentiate into various functional cell types with broad application prospects in the treatment of tissue damage. The purpose of this study was to explore the protective effect of ASCs against radiation-induced lung injury and to provide a novel basis for prevention and treatment of radiation-induced lung injury.

Materials and methods

Fifty mice were randomly divided into a control group (Ctrl), radiation exposure group (IR), radiation exposure plus ASC treatment group (IR + ASC), radiation exposure plus L-257 group (IR + L-257), and radiation exposure plus ASC treatment and L-257 group (IR + ASC + L-257). Mice in IR, IR + ASC, and IR + ASC + L-257 groups were exposed to a single whole-body dose of 5 Gy X-rays (160 kV/25 mA, 1.25 Gy/min). Within 2 h after irradiation, mice in IR + ASC and IR + ASC + L-257 groups were injected with 5 × 106 ASCs via the tail vein. Mice in IR + L-257 and IR + ASC + L-257 groups were intraperitoneally injected with 30 mg/kg L-257 in 0.5 mL saline.

Results

The mice in the IR group exhibited lung hemorrhage, edema, pulmonary fibrosis, and inflammatory cell infiltration, increased release of proinflammatory cytokines, elevation of oxidative stress and apoptosis, and inhibition of the dimethylarginine dimethylamino hydratase 1 (DDAH1)/ADMA/eNOS signaling pathway. ASC treatment alleviated radiation-induced oxidative stress, apoptosis, and inflammation, and restored the DDAH1/ADMA/eNOS signaling pathway. However, L-257 pretreatment offset the protective effect of ASCs against lung inflammation, oxidative stress, and apoptosis.

Conclusions

These data suggest that ASCs ameliorate radiation-induced lung injury, and the mechanism may be mediated through the DDAH1/ADMA/eNOS signaling pathway.

Recent advances in host-focused molecular tools for investigating host-gut microbiome interactions

Microbial communities in the human gut play a significant role in regulating host gene expression, influencing a variety of biological processes. To understand the molecular mechanisms underlying host-microbe interactions, tools that can dissect signaling networks are required. In this review, we discuss recent advances in molecular tools used to study this interplay, with a focus on those that explore how the microbiome regulates host gene expression. These tools include CRISPR-based whole-body genetic tools for deciphering host-specific genes involved in the interaction process, Cre-loxP based tissue/cell-specific gene editing approaches, and in vitro models of host-derived organoids. Overall, the application of these molecular tools is revolutionizing our understanding of how host-microbiome interactions contribute to health and disease, paving the way for improved therapies and interventions that target microbial influences on the host.

Asperuloside regulates the proliferation, apoptosis, and differentiation of chronic myeloid leukemia cell line K562 through the RAS/MEK/ERK pathway

Context

Chronic myeloid leukemia (CML) is a malignant hematopoietic stem cell disease caused by excessive proliferation and abnormal differentiation of hematopoietic stem cells. Asperuloside (ASP) is considered to have good biological activity and may be a good anti-CML drug.

Objective

This study aimed to explore the effects and possible mechanisms of ASP on the biological behavior of K562 cells based on RNA-seq.

Materials and methods

The IC50 of ASP in K562 cells was calculated by the concentration-effect curve. Cell viability, apoptosis, and differentiation were detected by CCK8, flow cytometry, benzidine staining, and WB analysis, respectively. Further, RNA-seq was used to analyze the possible mechanism of ASP regulating K562 cells.

Results

ASP significantly inhibited the proliferation, and promoted apoptosis and differentiation of K562 cells. A total of 117 differentially expressed genes were screened by RNA-seq, mainly involved in the RAS/MEK/ERK pathway. PD98059 was used to inhibit the RAS/MEK/ERK pathway in K562 cells, and results confirmed that PD98059 could not only inhibit the RAS/MEK/ERK pathway, but also inhibit the regulation of ASP on the proliferation and differentiation of K562 cells.

Conclusion

ASP inhibited the proliferation, promoted apoptosis and differentiation of K562 cells by regulating the RAS/MEK/ERK pathway, and played a good anti-CML role.

Evaluation of the Cytotoxicity of Secondary Bioactive Compounds Produced by Streptomyces in Soil against a Colon Cancer Cell Line

Colorectal cancer is one of the most serious malignancies affecting humans. In this study, Streptomyces bioactive chemicals extracted from soil were analyzed for their anti-colorectal-cancer and antibacterial properties. A total of 100 soil samples were collected from Kerman-Iran, incubated in SCA media and the antimicrobial properties were tested using the cross-streak method. Three strains were cultured in ISP4 medium to obtain secondary bioactive compounds. After studying the effects of the bioactive compounds on the HT29 and human foreskin fibroblast (HFF) cell lines, the expression of the p53, p21, BAX, BCL2, Casp3 and Casp8 genes was analyzed by real-time PCR and flow cytometry to detect the presence of apoptosis.The isolates show high degree of identification with Streptomyces rochei, Streptomyces fungicidicus and Streptomyces maritimus due to 16SrDNA sequence homology. Compared to HT-29 cells, Streptomyces extracts had lower cytotoxicity against normal cells (SI=5.88), followed by HFF (SI=4.14). The cell lines demonstrated a dose-dependent significant increase in DNA fragmentation, an increase in the proportion of cells in sub-G1 phase and caused G2/M cell cycle arrest in HT-29 and HFF cells.The bacterial extracts obtained displayed strong antibacterial properties and inhibited the proliferation of HT-29 and HFF cell lines. The treated cells exhibited morphological changes caused by the activation of caspase and p53/p21 proteins. This confirms that Streptomyces-induced apoptosis is mediated by the activation of p21/p53. Anti-apoptotic Bcl-2 gene expression was downregulated by treatment with the extracts. Further studies are needed to understand the antimicrobial properties of Streptomyces.

Reprogramming of VEGF-mediated extracellular matrix changes through autocrine signaling

Vascular endothelial growth factor (VEGF) plays key roles in angiogenesis, vasculogenesis, and wound healing. In cancers, including triple negative breast cancer (TNBC), VEGF has been associated with increased invasion and metastasis, processes that require cancer cells to traverse through the extracellular matrix (ECM) and establish angiogenesis at distant sites. To further understand the role of VEGF in modifying the ECM, we characterized VEGF-mediated changes in the ECM of tumors derived from TNBC MDA-MB-231 cells engineered to overexpress VEGF. We established that increased VEGF expression by these cells resulted in tumors with reduced collagen 1 (Col1) fibers, fibronectin, and hyaluronan. Molecular characterization of tumors identified an increase of MMP1, uPAR, and LOX, and a decrease of MMP2, and ADAMTS1. α-SMA, a marker of cancer associated fibroblasts (CAFs), increased, and FAP-α, a marker of a subset of CAFs associated with immune suppression, decreased with VEGF overexpression. Analysis of human data from The Cancer Genome Atlas Program confirmed mRNA differences for several molecules when comparing TNBC with high and low VEGF expression. We additionally characterized enzymatic changes induced by VEGF overexpression in three different cancer cell lines that clearly identified autocrine-mediated changes, specifically uPAR, in these enzymes. Unlike the increase of Col1 fibers and fibronectin mediated by VEGF during wound healing, in the TNBC model, VEGF significantly reduced key protein components of the ECM. These results further expand our understanding of the role of VEGF in cancer progression and identify potential ECM-related targets to disrupt this progression.

Small RNA Deep Sequencing of Circulating Small RNAs Discovers a Unique Panel of microRNAs as Feasible and Reliable Biomarkers of Non-Small Cell Lung Cancers in Northern Thailand

OBJECTIVE

This study aimed to assess the practicality and reliability of utilizing microRNAs (miRNAs) as a potential screening and diagnosing tool for non-small cell lung cancers (NSCLCs) in Northern Thailand.

METHODS

Small RNA sequencing and a literature review was performed to obtain a list of serum miRNA candidates. Serum levels of these selected miRNA candidates were measured in patients with NSCLC and healthy volunteers by real-time RT-PCR and receiver operating characteristic curve (ROC) were used to assess diagnostic performance.

RESULTS

Sequencing data revealed 148 known miRNAs and 230 novel putative miRNAs in serum samples; 19 serum miRNAs were significantly downregulated and 242 were upregulated. Seven miRNAs selected according to sequencing data and 11 miRNAs according to previous reports were evaluated in training cohort (45 lung cancer patients, 26 controls) and 6 miRNAs were found differentially expressed (p < 0.05, Mann Whitney U test) and associated (p < 0.05, Chi-square test) with NSCLC development. Further analysis and verification identified an optimal combination of 4 miRNAs composed of hsa-miR23a, hsa-miR26b, hsa-miR4488 and novel-130 to provide the optimal AUC of 0.901±0.034. Detection of serum miRNA by real-time RT-PCR showed good reproducibility with the coefficient of variation (CV) ≤ 4%. The optimal screening miRNAs panel was primarily identified through sequencing data of local patient population, thus indicating that the etiology of NSCLCs may differ from one population to other and thus require a unique panel of miRNAs for their identification.

CONCLUSION

Circulating miRNA is a feasible screening tool for NSCLCs. Nevertheless, populations with different lung cancer etiology may need to identify their own most suitable miRNA panel.

Siglecs as potential targets of therapy in human mast cell- and/or eosinophil-associated diseases

Siglecs (sialic acid-binding immunoglobulin-like lectins) are a family of vertebrate glycan-binding cell-surface proteins. The majority mediate cellular inhibitory activity once engaged by specific ligands or ligand-mimicking molecules. As a result, Siglec engagement is now of interest as a strategy to therapeutically dampen unwanted cellular responses. When considering allergic inflammation, human eosinophils and mast cells express overlapping but distinct patterns of Siglecs. For example, Siglec-6 is selectively and prominently expressed on mast cells while Siglec-8 is highly specific for both eosinophils and mast cells. This review will focus on a subset of Siglecs and their various endogenous or synthetic sialoside ligands that regulate eosinophil and mast cell function and survival. It will also summarize how certain Siglecs have become the focus of novel therapies for allergic and other eosinophil- and mast cell-related diseases.

Comparison of Interleukin-33 Serum Levels in Patients with Breast Cancer and Idiopathic Granulomatous Mastitis

BACKGROUND

Breast cancer (BC) is the main cause of cancer death in women. Idiopathic granulomatous mastitis (IGM), a rare chronic disease that clinically mimics breast carcinoma, and is associated with high mortality and morbidity, but an immediate and accurate diagnosis can substantially decrease these rates. Expressed by numerous human tissues, interleukin-33 (IL-33) has an inductive role in the network of pro-inflammatory cytokines. The aim of this study was to investigate the serum levels of IL-33 in BC and IGM patients in comparison with healthy women.

MATERIALS AND METHODS

This descriptive-analytical study was carried out on 28 patients with BC and 25 patients with IGM as the patient groups and 25 healthy volunteers with normal screening reports as the control group. Histopathological pattern of BC and IGM were confirmed by specialized pathologists. The serum concentration of IL-33 was measured using enzyme-linked immunosorbent assay (ELISA) kit according to the manufacturer's instructions.

RESULTS

The mean age of the patients with BC and IGM and the control group was 49.1, 37.1, and 36.8 years, respectively. There was no significant difference in IL-33 expression among the participants with regard to age, marital status, body mass index (BMI), and menopausal status. IL-33 assay indicated a significant difference between the BC (P=0.011) and IGM (P=0.031) groups compared to the controls, although no substantial differences were observed between the IGM and BC groups.

CONCLUSION

IL-33 can be considered a significant factor distinguishing IGM and BC patients from controls, although it cannot be applied to diagnose and differentiate BC from IGM patients.
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Siglecs in allergy and asthma

The term "allergic diseases" encompasses several common, IgE-mediated conditions that range from being annoying to those that are life-threatening. Available treatments include active avoidance of the instigating allergen and the use of a variety of oral, inhaled, intranasal, intraocular and injected agents. While most individuals with allergies do well with existing therapies, there are still unmet therapeutic needs. Siglecs (sialic acid-binding, immunoglobulin-like lectins) are a family of single-pass transmembrane I-type lectins found on various subsets of cells, especially those of the immune system. All Siglecs have extracellular domains recognizing sialoside ligands, and most contain cytoplasmic domains with inhibitory signaling activity. This review focuses on Siglecs that likely play a role in regulating allergic and asthmatic responses, and how specific Siglecs, expressed on cells such as eosinophils and mast cells, are being targeted for therapeutic benefit.

Non-canonical roles of Siglecs: Beyond sialic acid-binding and immune cell modulation

Siglecs (Sialic acid-binding immunoglobulin-type lectins) are I-type lectins that bind with sialic acid ligands (Sia). Most are expressed on the surface of leukocytes and are involved in immune regulation and possess immune tyrosine-based inhibitory motif (ITIM) in the intracellular domain, thus leading to inhibition of the immune response. This signaling is instrumental in maintaining quiescence under physiological conditions and acts as a brake for inflammatory cascades. By contrast, activating Siglecs carry positively charged residues in the transmembrane domain and interact with immune tyrosine-based activating motif (ITAM)-containing proteins, a DNAX-activating protein of 10-12 kDa (DAP10/12), to activate immune cells. There are various characteristics of Siglecs that do not fit within the classification of Siglec receptors as being either inhibitory or activating in nature. This review focuses on elucidating the non-canonical functions and interactions of Siglec receptors, which include Sia-independent interactions such as protein-protein interactions and interactions with lipids or other sugars. This review also summarizes Siglec expression and function on non-immune cells, and non-classical signaling of the receptor. Thus, this review will be beneficial to researchers interested in the field of Siglecs and sialic acid biology.

Progress and promise of cell sheet assisted cardiac tissue engineering in regenerative medicine

Cardiovascular diseases (CVDs) are the most common leading causes of premature deaths in all countries. To control the harmful side effects of CVDs on public health, it is necessary to understand the current and prospective strategies in prevention, management, and monitoring CVDs.In vitro,recapitulating of cardiac complex structure with its various cell types is a challenging topic in tissue engineering. Cardiac tissue engineering (CTE) is a multi-disciplinary strategy that has been considered as a novel alternative approach for cardiac regenerative medicine and replacement therapies. In this review, we overview various cell types and approaches in cardiac regenerative medicine. Then, the applications of cell-sheet-assisted CTE in cardiac diseases were discussed. Finally, we described how this technology can improve cardiac regeneration and function in preclinical and clinical models.

Cerebral Theta-Burst Stimulation Combined with Physiotherapy in Patients with Incomplete Spinal Cord Injury: A Pilot Randomized Controlled Trial

OBJECTIVE

To measure the effects of cerebral intermittent theta-burst stimulation with physiotherapy on lower extremity motor recovery in patients with incomplete spinal cord injury.

DESIGN

Randomized, double-blinded, sham-controlled trial.

SUBJECTS

Adults with incomplete spinal cord injury.

METHODS

A total of 38 patients with incomplete spinal cord injury were randomized into either an intermittent theta-burst stimulation or a sham group. Both groups participated in physiotherapy 5 times per week for 9 weeks, and cerebral intermittent theta-burst stimulation or sham intermittent theta-burst stimulation was performed daily, immediately before physiotherapy. The primary outcomes were lower extremity motor score (LEMS), root-mean square (RMS), RMS of the quadriceps femoris muscle, walking speed (WS), and stride length (SL). Secondary outcomes comprised Holden Walking Ability Scale (HWAS) and modified Barthel Index (MBI). The outcomes were assessed before the intervention and 9 weeks after the start of the intervention.

RESULTS

Nine weeks of cerebral intermittent theta-burst stimulation with physiotherapy intervention resulted in improved recovery of lower extremity motor recovery in patients with incomplete spinal cord injury. Compared with baseline, the changes in LEMS, WS, SL, RMS, HWAS, and MBI were significant in both groups after intervention. The LEMS, WS, SL, RMS, HWAS, and MBI scores were improved more in the intermittent theta-burst stimulation group than in the sham group.

CONCLUSION

Cerebral intermittent theta-burst stimulation with physiotherapy promotes lower extremity motor recovery in patients with incomplete spinal cord injury. However, this study included a small sample size and lacked a comparison of the treatment effects of multiple stimulation modes, the further research will be required in the future.

Drug delivery targets and strategies to address mast cell diseases

INTRODUCTION

Current and developing mast cell therapeutics are reliant on small molecule drugs and biologics, but few are truly selective for mast cells. Most have cellular and disease-specific limitations that require innovation to overcome longstanding challenges to selectively targeting and modulating mast cell behavior. This review is designed to serve as a frame of reference for new approaches that utilize nanotechnology or combine different drugs to increase mast cell selectivity and therapeutic efficacy.

AREAS COVERED

Mast cell diseases include allergy and related conditions as well as malignancies. Here, we discuss the targets of existing and developing therapies used to treat these disease pathologies, classifying them into cell surface, intracellular, and extracellular categories. For each target discussed, we discuss drugs that are either the current standard of care, under development, or have indications for potential use. Finally, we discuss how novel technologies and tools can be used to take existing therapeutics to a new level of selectivity and potency against mast cells.

EXPERT OPINION

There are many broadly and very few selectively targeted therapeutics for mast cells in allergy and malignant disease. Combining existing targeting strategies with technology like nanoparticles will provide novel platforms to treat mast cell disease more selectively.

P19 a Parthenin Analog Induces Cell Lineage Dependent Apoptotic and Immunomodulatory Signaling in Acute Lymphoid Leukemia Cells

Leukemia is a type of cancer that affects the blood and bone marrow. Acute lymphoid leukaemia, also known as ALL, is regarded as one of the deadliest forms of cancer. Due to the rapid increase in various cancer cases and the development of resistance in cancer cells, it is necessary to identify novel lead molecules with more potent anticancer properties. There is a growing interest in using herbal products/analogs as multi-component agents (as anticancer agents and immunomodulators) for cancer treatment. In the present investigation, an attempt has been made to explore the anticancer and immunomodulatory activity of P19, an analog of parthenin in ALL. P19 was reported to exhibit anticancer efficacy by triggering apoptotic signaling events in human leukaemia HL-60 cells by significant NO production. In contrast to this finding, ROS and NO were not required for P19-mediated apoptosis in Raji cells. The mechanism of action of P19 was observed to be cancer cell lineage dependent. P19 demonstrated very effective anticancer properties against ALL (IC50 3µM). Molecular investigations revealed that P19 induced mitochondrion mediated apoptosis by Bax localization to mitochondria and enhanced cytosolic calcium in the cytoplasm. Further activation of the caspase 3, caspase 8 and PARP cleavage suggested the involvement of the caspase-mediated apoptosis. Anti-proliferative activity revealed the telomerase inhibition and cell cycle arrest in G0/G1 phase after P19 treatment. Immunomodulatory effects of the P19 revealed the enhanced INFɣ and NO production in Jurkat and THP cells. Owing to its antiproliferative and immunomodulatory potential against leukemia cells P19 can further be explored as effective therapeutics against leukemia.

Molecular Pathways of Diabetic Kidney Disease Inferred from Proteomics

Diabetic kidney disease (DKD) affects an estimated 20-40% of type 2 diabetes patients and is among the most prevalent microvascular complications in this patient population, contributing to high morbidity and mortality rates. Currently, changes in albuminuria status are thought to be a primary indicator of the onset or progression of DKD, yet progressive nephropathy and renal impairment can occur in certain diabetic individuals who exhibit normal urinary albumin levels, emphasizing the lack of sensitivity and specificity associated with the use of albuminuria as a biomarker for detecting diabetic kidney disease and predicting DKD risk. According to the study, a non-invasive method for early detection or prediction of DKD may involve combining proteomic analytical techniques such second generation sequencing, mass spectrometry, two-dimensional gel electrophoresis, and other advanced system biology algorithms. Another category of proteins of relevance may now be provided by renal tissue biomarkers. The establishment of reliable proteomic biomarkers of DKD represents a novel approach to improving the diagnosis, prognostic evaluation, and treatment of affected patients. In the present review, a series of protein biomarkers that have been characterized to date are discussed, offering a theoretical foundation for future efforts to aid patients suffering from this debilitating microvascular complication.

Cancer Immunotherapy: The Checkpoint between Chronic Colitis and Colorectal Cancer

Inflammatory Bowel Disease (IBD) is a group of diseases that cause intestinal inflammation and lesions because of an abnormal immune response to host gut microflora. Corticosteroids, anti-inflammatories, and antibiotics are often used to reduce non-specific inflammation and relapse rates; however, such treatments are ineffective over time. Patients with chronic colitis are more susceptible to developing colorectal cancer, especially those with a longer duration of colitis. There is often a limit in using chemotherapy due to side effects, leading to reduced efficacy, leaving an urgent need to improve treatments and identify new therapeutic targets. Cancer immunotherapy has made significant advances in recent years and is mainly categorized as cancer vaccines, adoptive cellular immunotherapy, or immune checkpoint blockade therapies. Checkpoint markers are expressed on cancer cells to evade the immune system, and as a result checkpoint inhibitors have transformed cancer treatment in the last 5-10 years. Immune checkpoint inhibitors have produced long-lasting clinical responses in both single and combination therapies. Winnie mice are a viable model of spontaneous chronic colitis with immune responses like human IBD. Determining the expression levels of checkpoint markers in tissues from these mice will provide insights into disease initiation, progression, and cancer. Such information will lead to identification of novel checkpoint markers and the development of treatments with or without immune checkpoint inhibitors or vaccines to slow or stop disease progression.

Habb-e-Asgandh Suppresses Cell Proliferation and Induces Apoptosis through Mitochondria Dysfunction in Multiple Myeloma Cells (RPMI8226)

OBJECTIVE

This study was conducted to assess the anti-neoplastic properties of Habb-e-Asgandh in multiple myeloma cells (RPMI8226).

METHODS

Multiple myeloma cells (RPMI8226) were cultured according to the ATCC's instruction. The anti-proliferative effect of HeA was assessed by MTT assay and proliferating cellnuclear antigen (PCNA) activity. Cell cycle analysis, cellular apoptosis, and mitochondria membrane potential analysis was done by flow cytometry. Total antioxidants, migratory potential, angiogenesis and inflammatory biomarkers were also estimated after treatment of RPMI8226 with HeA.

RESULTS

LD30 and LD50 dose of HeA was 0.3mg/ml and 0.5mg/ml respectively determined by MTT assay and also confirmed by a reduced PCNA activity. Cell cycle analysis of RPMI8226 cells revealed that sub-G0/G1 phase increases upon treatment with HeA alone or in combination with lenalidomide. Annexin V-FITC/PI is used to detect early apoptosis, late apoptosis and necrotic cells and results showed that percentage of apoptotic cells increased in RPMI8226 cells after treatment with HeA. Also, HeA induces loss of mitochondria membrane potential (MMP) in MM cells in-vitro as measured by cationic JC1 dye staining. Upon treatment, the abnormal overexpression of oncogenic protein, AKT serine/threonine kinase has also been reduced. Furthermore, anti-oxidants level also increased while migratory potential, angiogenesis and inflammation decreased in multiple myeloma cell line upon treatment with HeA.

CONCLUSION

Collectively, our results demonstrated that integrative therapy of habb-e-asgandh efficiently eliminates the need to use higher dose of lenalidomide for multiple myeloma treatment.

Transgenic mouse models to study the physiological and pathophysiological roles of human Siglecs

Sialic acid-binding immunoglobulin-like lectins (Siglecs) are important immunomodulatory receptors. Due to differences between human and mouse Siglecs, defining the in vivo roles for human Siglecs (hSiglecs) can be challenging. One solution is the development and use of hSiglec transgenic mice to assess the physiological roles of hSiglecs in health and disease. These transgenic mice can also serve as important models for the pre-clinical testing of immunomodulatory approaches that are based on targeting hSiglecs. Four general methods have been used to create hSiglec-expressing transgenic mice, each with associated advantages and disadvantages. To date, transgenic mouse models expressing hSiglec-2 (CD22), -3 (CD33), -7, -8, -9, -11, and -16 have been created. This review focuses on both the generation of these hSiglec transgenic mice, along with the important findings that have been made through their study. Cumulatively, hSiglec transgenic mouse models are providing a deeper understanding of the differences between human and mice orthologs/paralogs, mechanisms by which Siglecs regulate immune cell signaling, physiological roles of Siglecs in disease, and different paradigms where targeting Siglecs may be therapeutically advantageous.

Nrf2 rs6721961 and Oxidative Stress in Preeclampsia: Association with the Risk of Preeclampsia and Early-Onset Preeclampsia

Preeclampsia as a multifactor hypertensive disorder of pregnancy is associated with enhanced placental oxidative stress. The Keap1-Nrf2 pathway protects cells against oxidative stress. We examined the possible association between the Nrf2 variants in relation to oxidative stress parameters with the risk of preeclampsia. We studied 150 preeclampsia women and 150 women with a normal pregnancy to find the frequency of Nrf2 rs6721961 genotypes using the PCR-RFLP method. Also, an association between the Nrf2 genotypes with the levels of malondialdehyde (MDA) and total antioxidant capacity (TAC) was analyzed. Significantly lower TAC and higher MDA levels were found in preeclampsia patients compared to controls (P<0.0001). For the first time, we report an association between the Nrf2 rs6721961 polymorphism and preeclampsia risk. The present study indicated that the GT genotype and the T allele of the Nrf2 rs6721961 increased the risk of preeclampsia by 2.81 and 2.39 times, respectively. Also, the Nrf2 TT genotype was associated with a 3.9-fold increased risk of early-onset preeclampsia. We detected a positive association between the levels of body mass index, MDA, and the Nrf2 polymorphism with the risk of preeclampsia and a negative correlation between the level of TAC with the preeclampsia risk. Also, an association between the rs6721961 TT genotype with higher serum MDA levels was found. Our study suggests oxidative stress is involved in the pathogenesis of preeclampsia and the Nrf2 rs6721961 polymorphism through alteration in the levels of oxidative stress parameters might increase the risk of preeclampsia and early-onset preeclampsia.

Kgp DNA Vaccine Prevents Experimental Periodontitis

PURPOSE

To investigate the prophylactic effect of lysine-specific protease (Kgp) vaccine on experimental periodontitis in mice.

MATERIALS AND METHODS

We constructed the eukaryotic expression plasmid pVAX1-kgp and immunised mice with the recombinant plasmid. Mice were divided into two groups and immunised with pVAX1-kgp or pVAX1 three times at 2-week intervals. Immunoglobulin (Ig)G, IgG1 and IgG2a antibodies were detected by enzyme-linked immunosorbent assay (ELISA) before and after immunisation. At the last immunisation, a silk ligature infiltrated with Porphyromonas gingivalis (P. gingivalis) was tied at the neck of the maxillary second molar to induce experimental periodontitis. Each group was euthanised after 10 days, and microcomputed tomography (micro-CT) and hematoxylin-eosin (HE) staining were used to detect the loss of alveolar bone.

RESULTS

Comparison with the pVAX1 group indicated that mice immunised with Kgp had higher levels of IgG (P < 0.05); the levels of the IgG1 were statistically significantly different (p < 0.05), and the levels of the IgG2a subtype were not significantly different. The results of micro-CT and HE staining showed that the alveolar bone loss in the pVAX1-kgp group was statistically significantly less than that in the pVAX1 group (p < 0.05). The expression of the related inflammatory factors, including interleukin-1β (IL-β), tumour necrosis factor (TNF-α) and interleukin-6 (IL-6), was lower in the pVAX1-kgp group than in the pVAX1 group.

CONCLUSION

The Kgp DNA vaccine can enhance IgG levels in a model of experimental periodontitis, effectively activate immunity, and mitigate alveolar bone loss.

Mast Cell-Specific Deletion of Group III Secreted Phospholipase A2 Impairs Mast Cell Maturation and Functions

Tissue-resident mast cells (MCs) have important roles in IgE-associated and -independent allergic reactions. Although microenvironmental alterations in MC phenotypes affect the susceptibility to allergy, understanding of the regulation of MC maturation is still incomplete. We previously reported that group III secreted phospholipase A2 (sPLA2-III) released from immature MCs is functionally coupled with lipocalin-type prostaglandin D2 (PGD2) synthase in neighboring fibroblasts to supply a microenvironmental pool of PGD2, which in turn acts on the PGD2 receptor DP1 on MCs to promote their proper maturation. In the present study, we reevaluated the role of sPLA2-III in MCs using a newly generated MC-specific Pla2g3-deficient mouse strain. Mice lacking sPLA2-III specifically in MCs, like those lacking the enzyme in all tissues, had immature MCs and displayed reduced local and systemic anaphylactic responses. Furthermore, MC-specific Pla2g3-deficient mice, as well as MC-deficient KitW-sh mice reconstituted with MCs prepared from global Pla2g3-null mice, displayed a significant reduction in irritant contact dermatitis (ICD) and an aggravation of contact hypersensitivity (CHS). The increased CHS response by Pla2g3 deficiency depended at least partly on the reduced expression of hematopoietic PGD2 synthase and thereby reduced production of PGD2 due to immaturity of MCs. Overall, our present study has confirmed that MC-secreted sPLA2-III promotes MC maturation, thereby facilitating acute anaphylactic and ICD reactions and limiting delayed CHS response.

Proceedings from the Inaugural American Initiative in Mast Cell Diseases (AIM) Investigator Conference

The American Initiative in Mast Cell Diseases (AIM) held its inaugural investigator conference at Stanford University School of Medicine in May 2019. The overarching goal of this meeting was to establish a Pan-American organization of physicians and scientists with multidisciplinary expertise in mast cell disease. To serve this unmet need, AIM envisions a network where basic, translational, and clinical researchers could establish collaborations with both academia and biopharma to support the development of new diagnostic methods, enhanced understanding of the biology of mast cells in human health and disease, and the testing of novel therapies. In these AIM proceedings, we highlight selected topics relevant to mast cell biology and provide updates regarding the recently described hereditary alpha-tryptasemia. In addition, we discuss the evaluation and treatment of mast cell activation (syndromes), allergy and anaphylaxis in mast cell disorders, and the clinical and biologic heterogeneity of the more indolent forms of mastocytosis. Because mast cell disorders are relatively rare, AIM hopes to achieve a coordination of scientific efforts not only in the Americas but also in Europe by collaborating with the well-established European Competence Network on Mastocytosis.

Biologics for the Use in Chronic Spontaneous Urticaria: When and Which

Guidelines for the treatment of chronic spontaneous urticaria (CSU) recommend the use of the IgE-targeted biologic omalizumab in patients with antihistamine-refractory disease. The rationale for this is supported by the key role of IgE and its high-affinity receptor, FcεRI, in the degranulation of skin mast cells that drives the development of the signs and symptoms of CSU, itchy wheals, and angioedema. Here, we review the current understanding of the pathogenesis of CSU and its autoimmune endotypes. We describe the mechanisms of action of omalizumab, the only biologic currently approved for CSU, its efficacy and ways to improve it, biomarkers for treatment response, and strategies for its discontinuation. We provide information on the effects of the off-label use, in CSU, of biologics licensed for the treatment of other diseases, including dupilumab, benralizumab, mepolizumab, reslizumab, and secukinumab. Finally, we discuss targets for novel biologics and where we stand with their clinical development. These include IgE/ligelizumab, IgE/GI-310, thymic stromal lymphopoietin/tezepelumab, C5a receptor/avdoralimab, sialic acid-binding Ig-like lectin 8/lirentelimab, CD200R/LY3454738, and KIT/CDX-0159. Our aim is to provide updated information and guidance on the use of biologics in the treatment of patients with CSU, now and in the near future.

Siglec Ligands

A dense and diverse array of glycans on glycoproteins and glycolipids decorate all cell surfaces. In vertebrates, many of these carry sialic acid, in a variety of linkages and glycan contexts, as their outermost sugar moiety. Among their functions, glycans engage complementary glycan binding proteins (lectins) to regulate cell physiology. Among the glycan binding proteins are the Siglecs, sialic acid binding immunoglobulin-like lectins. In humans, there are 14 Siglecs, most of which are expressed on overlapping subsets of immune system cells. Each Siglec engages distinct, endogenous sialylated glycans that initiate signaling programs and regulate cellular responses. Here, we explore the emerging science of Siglec ligands, including endogenous sialoglycoproteins and glycolipids and synthetic sialomimetics. Knowledge in this field promises to reveal new molecular pathways controlling cell physiology and new opportunities for therapeutic intervention.

Nanoparticles Displaying Allergen and Siglec-8 Ligands Suppress IgE-FcεRI-Mediated Anaphylaxis and Desensitize Mast Cells to Subsequent Antigen Challenge

Siglec-8 is an inhibitory receptor expressed on eosinophils and mast cells. In this study, we took advantage of a novel Siglec-8 transgenic mouse model to assess the impact of modulating IgE-dependent mast cell degranulation and anaphylaxis using a liposomal platform to display an allergen with or without a synthetic glycan ligand for Siglec-8 (Sig8L). The hypothesis is that recruitment of Siglec-8 to the IgE-FcεRI receptor complex will inhibit allergen-induced mast cell degranulation. Codisplay of both allergen and Sig8L on liposomes profoundly suppresses IgE-mediated degranulation of mouse bone marrow-derived mast cells or rat basophilic leukemia cells expressing Siglec-8. In contrast, liposomes displaying only Sig8L have no significant suppression of antigenic liposome-induced degranulation, demonstrating that the inhibitory activity by Siglec-8 occurs only when Ag and Sig8L are on the same particle. In mouse models of anaphylaxis, display of Sig8L on antigenic liposomes completely suppresses IgE-mediated anaphylaxis in transgenic mice with mast cells expressing Siglec-8 but has no protection in mice that do not express Siglec-8. Furthermore, mice protected from anaphylaxis remain desensitized to subsequent allergen challenge because of loss of Ag-specific IgE from the cell surface and accelerated clearance of IgE from the blood. Thus, although expression of human Siglec-8 on murine mast cells does not by itself modulate IgE-FcεRI-mediated cell activation, the enforced recruitment of Siglec-8 to the FcεRI receptor by Sig8L-decorated antigenic liposomes results in inhibition of degranulation and desensitization to subsequent Ag exposure.

Bruton's tyrosine kinase inhibition effectively protects against human IgE-mediated anaphylaxis

No known therapies can prevent anaphylaxis. Bruton's tyrosine kinase (BTK) is an enzyme thought to be essential for high-affinity IgE receptor (FcεRI) signaling in human cells. We tested the hypothesis that FDA-approved BTK inhibitors (BTKis) would prevent IgE-mediated responses including anaphylaxis. We showed that irreversible BTKis broadly prevented IgE-mediated degranulation and cytokine production in primary human mast cells and blocked allergen-induced contraction of isolated human bronchi. To address their efficacy in vivo, we created and used what we believe to be a novel humanized mouse model of anaphylaxis that does not require marrow ablation or human tissue implantation. After a single intravenous injection of human CD34+ cells, NSG-SGM3 mice supported the population of mature human tissue-resident mast cells and basophils. These mice showed excellent responses during passive systemic anaphylaxis using human IgE to selectively evoke human mast cell and basophil activation, and response severity was controllable by alteration of the amount of allergen used for challenge. Remarkably, pretreatment with just 2 oral doses of the BTKi acalabrutinib completely prevented moderate IgE-mediated anaphylaxis in these mice and also significantly protected against death during severe anaphylaxis. Our data suggest that BTKis may be able to prevent anaphylaxis in humans by inhibiting FcεRI-mediated signaling.

Discovery, Function, and Therapeutic Targeting of Siglec-8

Siglecs (sialic acid-binding immunoglobulin-like lectins) are single-pass cell surface receptors that have inhibitory activities on immune cells. Among these, Siglec-8 is a CD33-related family member selectively expressed on human mast cells and eosinophils, and at low levels on basophils. These cells can participate in inflammatory responses by releasing mediators that attract or activate other cells, contributing to the pathogenesis of allergic and non-allergic diseases. Since its discovery in 2000, initial in vitro studies have found that the engagement of Siglec-8 with a monoclonal antibody or with selective polyvalent sialoglycan ligands induced the cell death of eosinophils and inhibited mast cell degranulation. Anti-Siglec-8 antibody administration in vivo to humanized and transgenic mice selectively expressing Siglec-8 on mouse eosinophils and mast cells confirmed the in vitro findings, and identified additional anti-inflammatory effects. AK002 (lirentelimab) is a humanized non-fucosylated IgG1 antibody against Siglec-8 in clinical development for mast cell- and eosinophil-mediated diseases. AK002 administration has safely demonstrated the inhibition of mast cell activity and the depletion of eosinophils in several phase 1 and phase 2 trials. This article reviews the discovery and functions of Siglec-8, and strategies for its therapeutic targeting for the treatment of eosinophil- and mast cell-associated diseases.

Tools to study and target the Siglec-sialic acid axis in cancer

Siglecs are widely expressed on leucocytes and bind to ubiquitously presented glycans containing sialic acids (sialoglycans). Most Siglecs carry an immunoreceptor tyrosine-based inhibition motif (ITIM) and elicit an inhibitory intracellular signal upon ligand binding. A few Siglec receptors can, however, recruit immunoreceptor tyrosine-based activation motif (ITAM)-containing factors, which activate cells. The role of hypersialylation (the enhanced expression of sialoglycans) has recently been explored in cancer progression. Mechanistic studies have shown that hypersialylation on cancer cells can engage inhibitory Siglecs on the surface of immune cells and induce immunosuppression. These recent studies strongly suggest that the Siglec-sialic acid axis can act as a potential target for cancer immunotherapy. Moreover, the use of new tools and techniques is facilitating these studies. In this review, we summarise techniques used to study Siglecs, including different mouse models, monoclonal antibodies, Siglec fusion proteins, and sialoglycan arrays. Furthermore, we discuss the recent major developments in the study of Siglecs in cancer immunosuppression, tools, and techniques used in targeting the Siglec-sialic acid axis and the possibility of clinical intervention.

Transcriptional regulation of adipogenic marker genes for the improvement of intramuscular fat in Qinchuan beef cattle

The intramuscular fat content plays a crucial role in meat quality traits. Increasing the degree of adipogenesis in beef cattle leads to an increase in the content of intramuscular fat. Adipogenesis a complex biochemical process which is under firm genetic control. Over the last three decades, the Qinchuan beef cattle have been extensively studied for the improvement of meat production and quality traits. In this study, we reviewed the literature regarding adipogenesis and intramuscular fat deposition. Then, we summarized the research conducted on the transcriptional regulation of key adipogenic marker genes, and also reviewed the roles of adipogenic marker genes in adipogenesis of Qinchuan beef cattle. This review will elaborate our understanding regarding transcriptional regulation which is a vital physiological process regulated by a cascade of transcription factors (TFs), key target marker genes, and regulatory proteins. This synergistic action of TFs and target genes ensures the accurate and diverse transmission of the genetic information for the accomplishment of central physiological processes. This information will provide an insight into the transcriptional regulation of the adipogenic marker genes and its role in bovine adipogenesis for the breed improvement programs especially for the trait of intramuscular fat deposition.

Lung Cancer Combination Treatment: Evaluation of the Synergistic Effect of Cisplatin Prodrug, Vinorelbine and Retinoic Acid When Co-Encapsulated in a Multi-Layered Nano-Platform

Purpose

Lung cancer remains the leading cancer-associated deaths worldwide. Cisplatin (CIS) was often used in combination with other drugs for the treatment of non-small cell lung cancer (NSCLC). Prodrug is an effective strategy to improve the efficiency of drugs and reduce the toxicity. The aim of this study was to prepare and characterize CIS prodrug, vinorelbine (VNR), and all-trans retinoic acid (ATRA) co-delivered multi-layered nano-platform, evaluating their antitumor activity in vitro and in vivo.

Methods

Cisplatin prodrug (CISP) was synthesized. A multi-layered nano-platform contained CISP, VNR and ATRA were prepared and named CISP/VNR/ATRA MLNP. The physicochemical properties of CISP/VNR/ATRA MLNP were investigated. In vitro cytotoxicity against CIS-resistant NSCLC cells (A549/CIS cells) and Human normal lung epithelial cells (BEAS-2B cells) was investigated, and in vivo anti-tumor efficiency was evaluated on mice bearing A549/CIS cells xenografts.

Results

CISP/VNR/ATRA MLNP were spherical particles with particle size and zeta potential of 158 nm and 12.3 mV. CISP/VNR/ATRA MLNP (81.36%) was uptake by cancer cells in vitro. CISP/VNR/ATRA MLNP could significantly inhibit the in vivo antitumor growth and suspended the tumor volume from 1440 mm³ to 220 mm³.

Conclusion

It could be concluded that the CISP/VNR/ATRA MLNP may be used as a promising system for lung cancer combination treatment.

Frontline Science: Superior mouse eosinophil depletion in vivo targeting transgenic Siglec-8 instead of endogenous Siglec-F: Mechanisms and pitfalls

Eosinophils are important multifunctional granulocytes. When studying eosinophil function and its contribution to diseases, mouse models are often used. Mouse eosinophils selectively express sialic acid-binding immunoglobulin-like lectin (Siglec)-F. Its closest functional paralog on human eosinophils is Siglec-8. These Siglecs are being used to target eosinophils when exploring their mechanistic roles in disease and for potential therapeutic benefit. In order to facilitate preclinical studies of human Siglec-8, we developed transgenic mouse strains expressing human Siglec-8 only on the surface of eosinophils with or without endogenous Siglec-F and have begun characterizing various cellular functions in vitro and in vivo. Eosinophils from Siglec-8+ mice, with or without Siglec-F, responded to Siglec-8 antibody engagement in vitro by up-regulating surface CD11b, whereas Siglec-F antibody had no such effect. Engagement of Siglec-F or Siglec-8 with respective antibodies in vitro resulted in only modest increases in cell death. Administration of rat Siglec-F antibodies to mice led to a significant decrease in Siglec-F surface expression on eosinophils due to internalization, and thus appeared to decrease eosinophil numbers based on Siglec-F+ cells, but with proper gaiting strategies did not in fact result in significant eosinophil depletion. In marked contrast, administration of mouse Siglec-8 antibodies rapidly and effectively depleted eosinophils from blood and spleens of mice, but an F(ab')2 version did not, indicating an Fc-mediated mechanism for eosinophil depletion in vivo. Siglec-8 expressing mice with or without endogenous Siglec-F will be useful to study Siglec-8-based therapeutics, and may be a preferred approach when acute or chronic eosinophil depletion is needed.

Eosinophil and mast cell Siglecs: From biology to drug target

Mast cells and eosinophils are innate immune cells involved in both acute and chronic inflammatory responses. Siglecs are a family of cell surface receptors that share sialic acid binding activity. Over the past 20 years, our knowledge of the expression and function of Siglecs on cells of the immune system and others has greatly expanded, as has our understanding of their signaling, ligands, and possible roles in disease pathophysiology. Because of this, Siglecs have garnered interest as potential drug targets using strategies ranging from biologics to ligand-directed nanoparticles. This mini-review will highlight the state of our knowledge regarding human eosinophil and mast cell Siglecs, their biology, what they recognize, tools developed for in vitro and preclinical experimentation, and the status of ongoing efforts to develop drugs that engage eosinophil and mast cell Siglecs for potential therapeutic benefit.

Siglecs as Immune Cell Checkpoints in Disease

Sialic acid-binding immunoglobulin-type lectins (Siglecs) are expressed on the majority of white blood cells of the immune system and play critical roles in immune cell signaling. Through recognition of sialic acid-containing glycans as ligands, they help the immune system distinguish between self and nonself. Because of their restricted cell type expression and roles as checkpoints in immune cell responses in human diseases such as cancer, asthma, allergy, neurodegeneration, and autoimmune diseases they have gained attention as targets for therapeutic interventions. In this review we describe the Siglec family, its roles in regulation of immune cell signaling, current efforts to define its roles in disease processes, and approaches to target Siglecs for treatment of human disease.

Siglec-8 antibody reduces eosinophils and mast cells in a transgenic mouse model of eosinophilic gastroenteritis

Aberrant accumulation and activation of eosinophils and potentially mast cells (MCs) contribute to the pathogenesis of eosinophilic gastrointestinal diseases (EGIDs), including eosinophilic esophagitis (EoE), gastritis (EG), and gastroenteritis (EGE). Current treatment options, such as diet restriction and corticosteroids, have limited efficacy and are often inappropriate for chronic use. One promising new approach is to deplete eosinophils and inhibit MCs with a monoclonal antibody (mAb) against sialic acid-binding immunoglobulin-like lectin 8 (Siglec-8), an inhibitory receptor selectively expressed on MCs and eosinophils. Here, we characterize MCs and eosinophils from human EG and EoE biopsies using flow cytometry and evaluate the effects of an anti-Siglec-8 mAb using a potentially novel Siglec-8-transgenic mouse model in which EG/EGE was induced by ovalbumin sensitization and intragastric challenge. MCs and eosinophils were significantly increased and activated in human EG and EoE biopsies compared with healthy controls. Similar observations were made in EG/EGE mice. In Siglec-8-transgenic mice, anti-Siglec-8 mAb administration significantly reduced eosinophils and MCs in the stomach, small intestine, and mesenteric lymph nodes and decreased levels of inflammatory mediators. In summary, these findings suggest a role for both MCs and eosinophils in EGID pathogenesis and support the evaluation of anti-Siglec-8 as a therapeutic approach that targets both eosinophils and MCs.

Too Many False Targets for MicroRNAs: Challenges and Pitfalls in Prediction of miRNA Targets and Their Gene Ontology in Model and Non-model Organisms

Short ("seed") or extended base pairing between microRNAs (miRNAs) and their target RNAs enables post-transcriptional silencing in many organisms. These interactions allow the computational prediction of potential targets. In model organisms, predicted targets are frequently validated experimentally; hence meaningful miRNA-regulated processes are reported. However, in non-models, these reports mostly rely on computational prediction alone. Many times, further bioinformatic analyses such as Gene Ontology (GO) enrichment are based on these in silico projections. Here such approaches are reviewed, their caveats are highlighted and the ease of picking false targets from predicted lists is demonstrated. Discoveries that shed new light on how miRNAs evolved to regulate targets in various phyletic groups are discussed, in addition to the pitfalls of target identification in non-model organisms. The goal is to prevent the misuse of bioinformatic tools, as they cannot bypass the biological understanding of miRNA-target regulation.

Enhancement of Retinal Function and of Neural Conduction Along the Visual Pathway Induced by Treatment with Citicoline Eye Drops in Liposomal Formulation in Open Angle Glaucoma: A Pilot Electrofunctional Study

INTRODUCTION

To evaluate the retinal function and the relative neural conduction along the visual pathway after treatment with citicoline in liposomal formulation (CLF) eye drops in patients with open angle glaucoma (OAG).

METHODS

Twelve OAG patients (mean age ± standard deviation 52.58 ± 11.39 years, intraocular pressure < 18 mmHg under topical hypotensive treatment, Humphrey field analyzer mean deviation - 4.49 ± 2.46 dB) were enrolled. Only one eye of studied patients was treated with CLF eye drops (OMK1-LF^®, Omikron Italia, 3 drops/day) (CLF group, 12 eyes) over a period of 4 months. In CLF eyes, pattern electroretinogram (PERG), visual evoked potentials (VEP), and visual field test were assessed at baseline and at the end of treatment (month 4).

RESULTS

After treatment with CLF eye drops, a significant increase of PERG P50-N95 amplitude and a significant shortening of VEP P100 implicit time were found. In CLF eyes, the shortening of VEP P100 implicit time was significantly correlated with the increase of PERG P50-N95 amplitude.

CONCLUSION

Data from this pilot study suggest that treatment with CLF eye drops induces an enhancement of the retinal bioelectrical responses (increase of PERG amplitude) with a consequent improvement of the bioelectrical activity of the visual cortex (shortening of VEP implicit time).

FUNDING

Omikron Italia S.r.l. and Opko Health Europe.

ARPE-19-derived VEGF-containing exosomes promote neovascularization in HUVEC: the role of the melanocortin receptor 5

ARPE-19 retinal pigment epithelial cells cultured in a medium containing 35 mM D-glucose led to an augmented ROS formation and release of vascular endothelial factor (VEGF)-containing exosomes compared to ARPE-19 cells cultured in a medium containing 5 mM D-glucose (standard medium). Exposing these cells to the melanocortin 5 receptor agonist (MCR₅) PG-901 (10^-10M), for 9 d reduced ROS generation, the number of exosomes released and their VEGF content. In contrast, incubating the cells with the melanocortin receptor MCR₁ agonist BMS-470539 (10^-5 M) or with the mixed MCR_3/4 agonist MTII (0.30 nmol) did not produce any significant decrease in ROS levels. ARPE-19-derived VEGF-containing exosomes promoted neovascularization in human umbilical vein endothelial cells (HUVEC), an effect that was markedly reduced by PG-901 (10^-10M) but not by the MCR_3/4 agonist MTII (0.30 nmol) or the MCR₁ agonist BMS-470539 (10^-5 M). The MCR₅-related action in the ARPE-19 cells was accompanied by the increased expression of two coupled factors, cytochrome p4502E1 (CYP2E1) and nuclear factor kappa b (Nf-κB). These are both involved in high glucose signalling, in ROS generation and, interestingly, were reduced by the MCR₅ agonist in the ARPE-19 cells. Altogether, these data suggest that MCR₅ is a modulator of the responses stimulated by glucose in ARPE-19 cells, which might possibly be translated into a modulation of the retinal pigment epithelium response to diabetes in vivo.