Genetic variants in LGALS3 are related to lower galectin-3 serum levels and clinical outcomes in systemic sclerosis patients: A case-control study

The role of galectin-3 in patients with permanent and paroxysmal Atrial Fibrillation and echocardiographic parameters of left atrial fibrosis

BACKGROUND

Biochemical markers and imaging tests have been used with the aim of stratifying the risk and detecting atrial fibrosis. Speckle-tracking echocardiography (STE) is used for the detection of atrial fibrosis and Gal-3 provides an important prognostic value. The objective of the study was to assess the association between atrial fibrosis markers and serum levels, genetic polymorphisms and genic expression of galectin-3.

METHODS

206 patients with permanent AF and 70 patients with paroxysmal AF were included in the study. Real time PCR (TaqMan) system was used to study SNPs rs4652 and 4644 of the gene LGALS3. Serum levels of Gal-3 were determined by ELISA and STE was performed to assess fibrosis.

RESULTS

Mean age of individuals with permanent AF was 66.56 ± 12 years. As for the echocardiography results, those patients showed an decrease in the following parameters peak atrial longitudinal strain (PALS) (p = 0.002) when compared to the same parameters from the paroxysmal AF group of patients. There was a correlation between serum levels of Gal-3 and PALS in the group of patients with permanent AF; the lower the levels of gal-3, the lower the LA strain (r = 0.24; p = 0.01).

CONCLUSIONS

Echocardiographic findings showed association with the groups, and with serum levels of Gal-3 in patients with permanent AF. The distribution of allelic and genotypic frequencies, and of the haplotypes of polymorphism LGALS3 rs4652 and rs4644 did not present statistical variation, which suggests that those SNPs are not associated with the AF clinical forms (permanent and paroxysmal).

Construction and verification of atopic dermatitis diagnostic model based on pyroptosis related biological markers using machine learning methods

OBJECTIVE

The aim of this study was to construct a model used for the accurate diagnosis of Atopic dermatitis (AD) using pyroptosis related biological markers (PRBMs) through the methods of machine learning.

METHOD

The pyroptosis related genes (PRGs) were acquired from molecular signatures database (MSigDB). The chip data of GSE120721, GSE6012, GSE32924, and GSE153007 were downloaded from gene expression omnibus (GEO) database. The data of GSE120721 and GSE6012 were combined as the training group, while the others were served as the testing groups. Subsequently, the expression of PRGs was extracted from the training group and differentially expressed analysis was conducted. CIBERSORT algorithm calculated the immune cells infiltration and differentially expressed analysis was conducted. Consistent cluster analysis divided AD patients into different modules according to the expression levels of PRGs. Then, weighted correlation network analysis (WGCNA) screened the key module. For the key module, we used Random forest (RF), support vector machines (SVM), Extreme Gradient Boosting (XGB), and generalized linear model (GLM) to construct diagnostic models. For the five PRBMs with the highest model importance, we built a nomogram. Finally, the results of the model were validated using GSE32924, and GSE153007 datasets.

RESULTS

Nine PRGs were significant differences in normal humans and AD patients. Immune cells infiltration showed that the activated CD4+ memory T cells and Dendritic cells (DCs) were significantly higher in AD patients than normal humans, while the activated natural killer (NK) cells and the resting mast cells were significantly lower in AD patients than normal humans. Consistent cluster analysis divided the expressing matrix into 2 modules. Subsequently, WGCNA analysis showed that the turquoise module had a significant difference and high correlation coefficient. Then, the machine model was constructed and the results showed that the XGB model was the optimal model. The nomogram was constructed by using HDAC1, GPALPP1, LGALS3, SLC29A1, and RWDD3 five PRBMs. Finally, the datasets GSE32924 and GSE153007 verified the reliability of this result.

CONCLUSIONS

The XGB model based on five PRBMs can be used for the accurate diagnosis of AD patients.

Variants Tagging LGALS-3 Haplotype Block in Association with First Myocardial Infarction and Plasma Galectin-3 Six Months after the Acute Event

Galectin-3 is encoded by LGALS-3, located in a unique haplotype block in Caucasians. According to the Tagger server, rs4040064, rs11628437, and rs7159490 cover 82% (r² > 0.8) of the genetic variance of this HapBlock. Our aims were to examine the association of their haplotypes with first myocardial infarction (MI), changes in left ventricular echocardiographic parameters over time, and impact on plasma galectin-3 and LGALS-3 mRNA in peripheral blood mononuclear cells, both 6 months post-MI. The study group consisted of 546 MI patients and 323 controls. Gene expression was assessed in 92 patients and plasma galectin-3 in 189 patients. Rs4040064, rs11628437, rs7159490, and LGALS-3 mRNA expression were detected using TaqMan^® technology. Plasma galectin-3 concentrations were determined by the ELISA method. We found that the TGC haplotype could have a protective effect against MI (adjusted OR 0.19 [0.05-0.72], p = 0.015) and that the GAC haplotype had significantly higher galectin-3 concentrations (48.3 [37.3-59.4] ng/mL vs. 18.9 [14.5-23.4] ng/mL, p < 0.0001), both in males and compared to the referent haplotype GGC. Higher plasma Gal-3 was also associated with higher NYHA class and systolic dysfunction. Our results suggest that variants tagging LGALS-3 HapBlock could reflect plasma Gal-3 levels 6 months post-MI and may have a potential protective effect against MI in men. Further replication, validation, and functional studies are needed.

Increased Expression of Galectin-3 in Skin Fibrosis: Evidence from In Vitro and In Vivo Studies

Skin fibrosis is a hallmark of a wide array of dermatological diseases which can greatly impact the patients' quality of life. Galectin-3 (GAL-3) has emerged as a central regulator of tissue fibrosis, playing an important pro-fibrotic role in numerous organs. Various studies are highlighting its importance as a skin fibrotic diseases biomarker; however, there is a need for further studies that clarify its role. This paper aims to ascertain whether the expression of GAL-3 is increased in relevant in vitro and in vivo models of skin fibrosis. We studied the role of GAL-3 in vitro using normal human dermal fibroblasts (NHDF) and fibrocytes. In addition, we used a skin fibrosis murine model (BALB/c mice) and human biopsies of healthy or keloid tissue. GAL-3 expression was analyzed using real time PCR, Western blot and immunostaining techniques. We report a significantly increased expression of GAL-3 in NHDF and fibrocytes cell cultures following stimulation with transforming growth factor β1 (TGFβ1). In vivo, GAL-3 expression was increased in a murine model of systemic sclerosis and in human keloid biopsies. In sum, this study underlines the involvement of GAL-3 in skin fibrosis using several models of the disease and highlights its role as a relevant target.

Galectin-3 protects auditory function in female mice

Sex differences in the development of sensorineural hearing loss have been recognized in various inner ear disorders, but the molecular basis for such differences is poorly understood. Autosomal genes have been shown to cause sex differences in disease susceptibility, but many genes exerting sex-dependent effects on auditory function remain to be identified. Galectin-3 (Gal-3), a protein encoded by the autosomal gene Lgals3, is a member of the β-galactoside-binding protein family, and has been linked to multiple biological processes, including immune responses, apoptosis, and cell adhesion. Here, we investigated auditory function and hair cell integrity in Gal-3 knockout (KO, Lgals3^-/-) and wild-type (WT, Lgals3^+/+) mice from age 1 to 6 months. KO mice show a more rapid age-related increase in ABR thresholds compared to WT mice. Noticeably, the threshold deterioration in female KO mice is significantly greater than in the male KO and WT mice. The ABR threshold elevation manifests over a broad frequency range in female KO mice, whereas the threshold elevations are confined to high frequencies in the male KO and WT mice. Moreover, DPOAE input/output functions reveal a similar pattern of auditory dysfunction, with the female KO mice displaying a significantly greater reduction in DPOAE amplitudes than male KO mice and WT mice of both sexes. Finally, age-related outer hair cell loss is greater for female KO mice compared to male KO mice and WT mice of both sexes. Together, these results indicate that Gal-3 deficiency exacerbates age-related cochlear degeneration and auditory dysfunction in female mice. Our study identifies Gal-3 as a sex-dependent molecule for maintaining female cochlear integrity.

Galectins—Potential Therapeutic Targets for Neurodegenerative Disorders

Advancements in medicine have increased the longevity of humans, resulting in a higher incidence of chronic diseases. Due to the rise in the elderly population, age-dependent neurodegenerative disorders are becoming increasingly prevalent. The available treatment options only provide symptomatic relief and do not cure the underlying cause of the disease. Therefore, it has become imperative to discover new markers and therapies to modulate the course of disease progression and develop better treatment options for the affected individuals. Growing evidence indicates that neuroinflammation is a common factor and one of the main inducers of neuronal damage and degeneration. Galectins (Gals) are a class of β-galactoside-binding proteins (lectins) ubiquitously expressed in almost all vital organs. Gals modulate various cellular responses and regulate significant biological functions, including immune response, proliferation, differentiation, migration, and cell growth, through their interaction with glycoproteins and glycolipids. In recent years, extensive research has been conducted on the Gal superfamily, with Gal-1, Gal-3, and Gal-9 in prime focus. Their roles have been described in modulating neuroinflammation and neurodegenerative processes. In this review, we discuss the role of Gals in the causation and progression of neurodegenerative disorders. We describe the role of Gals in microglia and astrocyte modulation, along with their pro- and anti-inflammatory functions. In addition, we discuss the potential use of Gals as a novel therapeutic target for neuroinflammation and restoring tissue damage in neurodegenerative diseases.