Search Results (127)

Cell membrane glycosylations play a critical role in regulating cell signaling, adhesion, and immune recognition. Abnormal glycosylation is a hallmark of cancer and promotes tumor progression. Sulfatide (SM4), a glycosphingolipid synthesized by galactosylceramide sulfotransferase (CST), is frequently altered in cancers, including breast cancer. Our previous studies identified SM4 as an adhesive molecule that enhances metastasis through interactions with platelets and endothelium; however, its elevated levels increase apoptotic sensitivity and reduce tumorigenicity. Here, we elucidate the molecular mechanisms linking sulfatide metabolism to apoptosis and gene regulation. Using MDA-MB-231 and MDA-MB-468 breast cancer cells with altered CST/SM4 levels, RNA sequencing and functional analyses revealed that overproduction of the CST/SM4 significantly downregulated BOLA2, a gene in the CIAPIN1 pathway involved in apoptosis. RT-qPCR and Western blot confirmed an inverse relationship between CST/SM4 and BOLA2. Overexpressing BOLA2 provided resistance to doxorubicin-induced apoptosis, suggesting that SM4-mediated repression of BOLA2 increases apoptotic sensitivity. Luciferase assays showed reduced BOLA2 promoter activity in SM4-enriched cells. Transcription factor profiling and Electrophoretic Mobility Shift Assay demonstrated that SM4 suppresses STAT5 activation, which directly binds and regulates the BOLA2 promoter. SM4 also altered integrin profiles by upregulating β4/β5 and downregulating β1 subunits. Reintroducing β1 integrin restored STAT5 activation and BOLA2 expression, positioning β1 integrin upstream of STAT5. Collectively, these findings identify a novel sulfatide-dependent β1 integrin–STAT5–BOLA2 pathway controlling apoptosis in breast cancer cells. SM4 suppresses β1 integrin and STAT5-mediated BOLA2 transcription, promoting apoptosis, while β4/β5 upregulation may facilitate invasion. This pathway represents a potential therapeutic target in breast cancer. Full article

Chondroitin sulfate (CS) chains on the cell surface are sulfated in various patterns, and this structure is the basis of CS function. We aimed to investigate the role of chondroitin 4-O-sulfotransferase-1 (C4ST-1), the enzyme responsible for the 4-sulfation of CS, in redox homeostasis and protein aggregation in mouse neuroblastoma Neuro2a and neural progenitor C17.2 cells. Results showed that C4ST-1 deficiency significantly reduced 4-sulfated CS, which led to markedly decreased intracellular glutathione levels and increased reactive oxygen species production. Mechanistically, C4ST-1 loss reduced the CS modification of neurocan, decreased the stability of the cystine transporter xCT, and decreased intracellular glutathione levels. This redox imbalance promoted protein aggregation and caused lysosomal membrane damage, indicating a failure of protein quality control. Although C4ST-1 deficiency alone did not cause tau protein aggregation, it significantly accelerated the aggregation of a familial tauopathy mutant following the introduction of seeds. These findings suggest that C4ST-1-mediated CS sulfation regulates the intracellular redox state and tau pathology. Thus, C4ST-1 may serve as a therapeutic target for neurodegenerative diseases. Full article

Thrombospondin-1 potently inhibits T cell activation by engaging its cell surface receptor CD47. This inhibitory signal requires glycosaminoglycan modification of CD47. CD47 also regulates the composition of RNAs in extracellular vesicles released by T cells and their functional activities. Because CD47 is also present in extracellular vesicles, we examined the effect of T cell activation on CD47 glycoforms in T cells and extracellular vesicles released by these cells. Activation increased both heparan and chondroitin sulfate biosynthesis by globally inducing mRNA levels of the respective glycosaminoglycan synthases and sulfotransferases. T cell activation in the presence of thrombospondin-1 inhibited induction of these biosynthetic enzymes, but not in cells lacking CD47. Therefore, CD47 signaling controls its own post-translational modification by glycosaminoglycans that are required for thrombospondin-1 signaling. Activation of Jurkat T lymphoblasts and primary CD4 and CD8 T cells increased the release of proteoglycan isoforms of CD47 and amyloid precursor-like protein-2 associated with extracellular vesicles and smaller macromolecular complexes. However, cell surface levels of CD47 were minimally changed during activation. BJAB and RAJI B cell lines also produced CD47⁺ extracellular vesicles and showed increased release of highly glycosylated CD47 following B cell receptor engagement. Therefore, T and B lymphocyte activation results in a selective increase in the synthesis and release of extracellular vesicles containing proteoglycan isoforms of CD47. Full article

Phenolic compounds contribute significantly to the nutritional and functional properties of wheat, particularly due to their antioxidant activity. In this study, a genome-wide association study was conducted to elucidate the genetic basis of total phenolic content (TPC) and antioxidant activity (AA) in a panel of 144 tetraploid wheat accessions representing diverse subspecies. The panel was evaluated under two different environments, located in Chile and Italy, to assess the influence of genotype, environment, and their interaction. Significant variability was observed for both TPC and AA, with TPC ranging from 0.26 to 0.82 mg gallic acid equivalent (GAE)/g and AA from 0.04 to 0.99 µmol Trolox equivalent (TE)/g. Substantial phenotypic variation and high broad-sense heritability were observed for both traits, underscoring the predominant genetic control. The genome-wide association study, using a mixed linear model (MLM), and the Bayesian information and Linkage-disequilibrium Iteratively Nested Keyway (BLINK) approaches identified 17 significant marker–trait associations, including quantitative trait loci on chromosomes 2B, 3A, 4B, 5A, 5B, and 6B. Notably, QTLs on chromosome 5A were co-localized for both TPC and AA, suggesting potential pleiotropic loci. Candidate genes linked to these loci included flavonol 3-sulfotransferase and peptidylprolyl isomerase, which are involved in phenylpropanoid metabolism and oxidative stress response, respectively. These findings offer valuable insights into the genetic basis of wheat phenolic traits and provide molecular targets for the development of biofortified cultivars through marker-assisted selection. Full article

Sulfotransferase (SULT) enzymes contribute significantly to drug metabolism in pediatric patients. The purpose of this study was to develop a PBPK model for acetaminophen (APAP) in pediatric populations that accounts for the ontogeny of SULT isozymes that play a critical role in APAP metabolism. PBPK modeling and simulation were performed using the Simcyp^® Simulator. The model incorporated the developmental ontogeny of three key hepatic SULT enzymes: SULT1A1, SULT1A3, and SULT2A1 using “best-fit” ontogeny equations for each isozyme as determined by nonlinear regression analysis of enzyme abundance versus age. PBPK model-simulated pharmacokinetic profiles for APAP captured observed clinical data for systemic exposure (Cmax, AUC) in neonates, infants, and children. SULTS accounted for ~60% APAP metabolism in neonates, with decreased contributions to infants and children. Model sensitivity analysis highlighted the potential for APAP metabolic DDIs, primarily through SULT1A1. The study demonstrates that the impact of SULT enzymes on drug metabolism is significant in neonates, which is an important clinical consideration for APAP. A PBPK model that incorporates SULT ontogeny has the potential to help inform dosing decisions in this special patient population. Full article

Background: Heparan sulfate (HS) is widely implicated as a receptor for Chlamydia cell attachment and infectivity. However, the enzymatic modification of HS modified by the 3-O sulfotransferase-3 (3-OST-3) enzyme in chlamydial cell entry remains unknown. Methodology: To rule out the possibility that host cell 3-O sulfated heparan sulfate (3-OS HS) plays a significant role in C. muridarum entry, a Chinese hamster ovary (CHO-K1) cell model lacking endogenous 3-OST-3 was used. In addition, we further tested the efficacy of the phage-display-derived cationic peptides recognizing heparan sulfate (G1 peptide) and the moieties of 3-O sulfated heparan sulfate (G2 peptide) against C. muridarum entry using human cervical adenocarcinoma (HeLa 229) and human vaginal epithelial (VK2/E6E7) cell lines. Furthermore, molecular dynamics simulations were conducted to investigate the interactions of the Chlamydia lipid bilayer membrane with the G1 and G2 peptides, focusing on their binding modes and affinities. Results: The converse effect of 3-OST-3 expression in the CHO-K1 cells had no enhancing effect on C. muridarum entry. The G2 peptide significantly (>80%) affected the cell infectivity of the elementary bodies (EBs) at all the tested concentrations, as evident from the reduced fluorescent staining in the number of inclusion bodies. The observed neutralization effect of G2 peptide on C. muridarum entry suggests the possibility of sulfated-like domains being present on the EBs. In addition, data generated from our in silico computational structural modeling indicated that the G2 peptide ligand had significant affinity towards the C. muridarum lipid bilayer. Conclusions: Taken together, our findings show that the pretreatment of C. muridarum with 3-O sulfated heparan sulfate recognizing G2 peptide significantly prevents the entry of EBs into host cells. Full article

Multiple sclerosis (MS) is a long-term disease that causes inflammation and damage to the nervous system. This study evaluated steroidomic alterations related to MS in 57 female MS patients during the follicular phase and 17 during the luteal phase, as well as in age- and phase-matched controls. The data showed that (1) unconjugated and conjugated steroids were strongly linked between the blood and CSF. (2) MS patients have lower levels of unconjugated steroids compared to controls. However, unchanged levels of conjugated steroids suggest a possible increase in steroid sulfotransferase functioning. (3) MS patients show altered levels of steroids linked to 11β-hydroxylase (CYP11B1) function. While direct enzyme activity was not measured, disrupted cortisol biosynthesis—potentially linked to reduced functioning of both CYP11B1 and 17α-hydroxylase/17,20-lyase—is associated with more severe cases of MS. (4) Reduced levels of 5α/β-steroids and protective GABAergic 3α-hydroxy-5α/β-steroids in MS patients might be linked to the pathophysiology of MS. (5) A potential increase in AKR1C3 function in MS could contribute to inflammation, as this enzyme catalyzes the synthesis of both steroids and prostaglandins. However, direct measurements of enzyme activity are needed to confirm this hypothesis. (6) Lower pregnenolone levels in MS patients might weaken neuroprotection, while higher pregnenolone sulfate levels could support cognitive function. (7) Lower levels of protective pregnenolone, DHEA, and androstenediol were associated with worse MS, suggesting these steroids may help shield against the disease. Full article

Mesothelioma is characterized by the inactivation of tumor suppressor genes, with frequent mutations in neurofibromin 2 (NF2), BRCA1-associated protein 1 (BAP1), and cyclin-dependent kinase inhibitor 2A (CDKN2A). These mutations lead to disruptions in the Hippo signaling pathway and histone methylation, thereby promoting tumor growth. NF2 mutations result in Merlin deficiency, leading to uncontrolled cell proliferation, whereas BAP1 mutations impair chromatin remodeling and hinder DNA damage repair. Emerging molecular targets in mesothelioma include mesothelin (MSLN), oxytocin receptor (OXTR), protein arginine methyltransferase (PRMT5), and carbohydrate sulfotransferase 4 (CHST4). MSLN-based therapies, such as antibody–drug conjugates and immunotoxins, have shown efficacy in clinical trials. OXTR, upregulated in mesothelioma, is correlated with poor prognosis and represents a novel therapeutic target. PRMT5 inhibition is being explored in tumors with MTAP deletions, commonly co-occurring with CDKN2A loss. CHST4 expression is associated with improved prognosis, potentially influencing tumor immunity. Immune checkpoint inhibitors targeting PD-1/PD-L1 have shown promise in some cases; however, resistance mechanisms remain a challenge. Advances in multi-omics approaches have improved our understanding of mesothelioma pathogenesis. Future research will aim to identify novel therapeutic targets and personalized treatment strategies, particularly in the context of epigenetic therapy and combination immunotherapy. Full article

Cholesterol sulfate (CS) is a naturally occurring cholesterol derivative that is widely distributed across various tissues and body fluids. In humans, its biosynthesis is primarily mediated by the sulfotransferase (SULT) 2B1b (SULT2B1b). Over the years, CS has been found to play critical roles in various physiological processes, including epidermal cell adhesion, sperm capacitation, platelet adhesion, coagulation, glucolipid metabolism, bone metabolism, gut microbiota metabolism, neurosteroid biosynthesis, T-cell receptor signaling, and immune cell migration. In this review, we first introduce the endogenous regulation of CS biosynthesis and metabolism. We then highlight current advances in the understanding of the physiological roles of CS. Finally, we delve into the implications of CS in various diseases, with a particular focus on its mechanism of action and potential therapeutic applications. A comprehensive understanding of CS’s physiological function, biosynthesis regulation, and role as a disease modifier offers novel insights that could pave the way for innovative therapeutic strategies targeting a wide range of conditions. Full article

Previously, we reported that mating induces an early transcriptional response in the oviductal mucosa of rats. The functional category ‘cell-to-cell signaling and interaction’ was overrepresented in this gene list. Therefore, in the present study, we describe the role of one of these genes, carbohydrate sulfotransferase 10 (Chst10), in the oviductal mucosa. CHST10 participates in the synthesis of the carbohydrate moiety human natural killer-1 (HNK-1), which mediates cell-to-cell interactions. When using one-dimensional Western blot and sulfotransferase analyses, we found that mating increased the protein level and activity of CHST10 in the oviductal mucosa at 3 h after stimulation. A two-dimensional Western blot analysis and mass spectrometry were used to identify the novel HNK-1 glycoproteins aldehyde dehydrogenase 9 family, member A1 (ALDH9A1), fructose bisphosphate aldolase A (ALDOA), and four and a half LIM domains protein 1 (FHL1) in the oviductal mucosa, and we found that mating induces the synthesis of their acidic variants. Interestingly, in the utero-tubal junction (UTJ), acrosome-reacted sperm apparently were interacting with regions in which ALDH9A1 and HNK-1 signals overlap. Furthermore, vaginocervical stimulation applied to unmated rats increased the mRNA level of Chst10 in the oviductal mucosa. In conclusion, mating increases the activity of CHST10 in the oviductal mucosa, which in turn induces the synthesis of acidic variants of ALDH9A1 and FHL1 via HNK-1 glycosylation. ALDH9A1, HNK-1-ALDH9A1, and/or other HNK-1 glycoproteins could participate in the negative selection of sperm in the UTJ, since we detected acrosome-reacted sperm apparently interacting with regions where these proteins are located. Finally, the sensorial component of mating could regulate early events (e.g., sperm transport and selection) occurring in the oviductal mucosa after mating. Full article

Background: Aging is associated with the development of various disorders, including postural imbalance, which increases the risk of falls and related health complications. This study examines changes in static postural balance after a 4-week intervention involving appropriate exercise and an optimized daily regimen. Additionally, it explores the relationship between these changes and the steroidome. Methods: The study was conducted on a clinically homogeneous group of 41 females around their sixth decade, diagnosed with anxiety-depressive syndrome and treated with selective serotonin reuptake inhibitors (SSRIs). Postural balance was assessed using the dual-scales method (DLLL-DSM), which estimates postural imbalance by evaluating differences in the lower limb load in the standing position. Correlations between initial DLLL-DSM values, age, BMI, and the baseline levels of nine serum steroids, as well as post-intervention changes in five steroids, were analyzed using multivariate regression (OPLS model). Results: A significant reduction in lower limb load differences (-ΔDLLL-DSM), indicating improved postural balance, was observed. The -ΔDLLL-DSM strongly correlated with initial DLLL-DSM values, age, BMI, initial levels of nine serum steroids, and post-intervention changes in five steroids (R = 0.892, p < 0.001). Furthermore, initial DLLL-DSM values negatively correlated with adrenal androgen androstenediol sulfate and various sulfated 5α/β-reduced androgen metabolites (R = 0.323, p < 0.05), suggesting that the activity of steroid sulfotransferase (SULT2A1) and C17-hydroxylase-C17,20-lyase (CYP17A1) at the lyase step is negatively associated with postural imbalance in elderly females. Conclusions: The findings suggest that even severe postural imbalance can be effectively and relatively rapidly improved through an appropriate exercise-based intervention and an optimized daily regimen, provided that initial adrenal activity is not significantly impaired. Additionally, the identified associations between steroid levels and postural balance provide new insights into the hormonal mechanisms regulating balance control in older individuals. Full article

Some marine and extremophilic microorganisms are capable of synthesizing sulfated polysaccharides with a unique structure. A number of studies indicate significant biological properties of individual sulfated polysaccharides, such as antiproliferative activity, which makes them a promising area for further research. In this study, the capsular polysaccharide (CPS) was obtained from the bacterium Cobetia marina KMM 1449, isolated from a marine sediment sample collected along the shore of the Sea of Japan. The CPS was isolated by saline solution, purified by a series of chromatographic procedures, and studied by chemical methods along with 1D and 2D ¹H and ¹³C NMR spectroscopy. The following new structure of the CPS from C. marina KMM 1449 was established and consisted of sulfated and simultaneously phosphorylated disaccharide repeating units: →4)-α-L-Rhap2S-(1→3)-β-D-Manp6PGro-(1→. To elucidate the genetic basis of the CPS biosynthesis, the whole genomic sequence of C. marina KMM 1449 was obtained. The CPS biosynthetic gene cluster (BGC) of about 70 genes composes four regions encoding nucleotide sugar biosynthesis (dTDP-Rha and GDP-Man), assembly (GTs genes), translocation (ABC transporter genes), sulfation (PAPS biosynthesis and sulfotransferase genes) and lipid carrier biosynthesis (wcb operon). Comparative analysis of the CPS BGCs from available Cobetia genomes showed the presence of KMM 1449-like CPS BGC among strains of all three Cobetia species. The study of new natural sulfated polysaccharides, as well as the elucidation of the pathways of their biosynthesis, provides the basis for the development of potential anticancer drugs. Full article

Background: Glycopeptide antibiotics (GPAs) are a very successful class of clinically relevant antibacterials, used to treat severe infections caused by Gram-positive pathogens, e.g., multidrug resistant and methicillin-resistant staphylococci. The biosynthesis of GPAs is coded within large biosynthetic gene clusters (BGCs). In recent years, modern DNA sequencing technologies have allowed the identification and characterization of multiple novel GPA BGCs, leading to the discovery of novel compounds. Our previous research anticipated that the genome of Amycolatopsis bartoniae DSM 45807^T carries a novel GPA BGC, although the genomic sequence quality available at that time did not allow us to characterize its organization properly. Objectives: To address this gap, in the current work we aimed to produce a complete genome assembly of A. bartoniae DSM 45807, and to identify and analyze the corresponding GPA BGC. Methods: Bioinformatic and microbiological methods were utilized in this research. Results: We de novo sequenced and completely assembled the genome of A. bartoniae DSM 45807, and fully characterized the BGC of interest, named aba. This BGC has an unusual gene organization and it contains four genes for sulfotransferases, which are considered to be rare in GPA BGCs. Our pathway prediction indicated that aba encodes the biosynthesis of a putatively novel GPA, although we were not able to detect any GPA production under different cultivation conditions, implying that aba pathway is inactive. Conclusions: Our results indicate aba as a promising source for new GPA tailoring enzymes. Full article

Sulfation plays a critical role in the biosynthesis of small molecules, regulatory mechanisms such as hormone signaling, and detoxification processes (phase II enzymes). The sulfation reaction is catalyzed by a broad family of enzymes known as sulfotransferases (SULTs), which have been extensively studied in animals due to their medical importance, but also in plant key processes. Despite the identification of some sulfated metabolites in fungi, the mechanisms underlying fungal sulfation remain largely unknown. To address this knowledge gap, we conducted a comprehensive search of available genomes, resulting in the identification of 174 putative SULT genes in the Ascomycota phylum. Phylogenetic analysis and structural modeling revealed that these SULTs belong to the aryl sulfotransferase family, and they are divided into two potential distinct clusters of PAPS-dependent SULTs within the fungal kingdom. SULT genes from two marine fungi isolated from deep-sea hydrothermal vents, Hortaea werneckii UBOCC-A-208029 (HwSULT) and Aspergillus sydowii UBOCC-A-108050 SULT (AsSULT), were selected as representatives of each cluster. Recombinant proteins were expressed in Escherichia coli and biochemically characterized. HwSULT demonstrated high and versatile activity, while AsSULT appeared more substrate-specific. Here, HwSULT was used to sulfate the mycotoxin zearalenone, enhancing its cytotoxicity toward healthy feline intestinal cells. Full article

Vibrio sp. KMM 8419 (=CB1-14) is a Gram-negative bacterium isolated from a food-net mucus sample of marine polychaete Chaetopterus cautus collected in the Sea of Japan. Here, we report the structure and biosynthetic gene cluster of the capsular polysaccharide (CPS) from strain KMM 8419. The CPS was isolated and studied by one- and two-dimensional ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy. The molecular weight of the CPS was about 254 kDa. The CPS consisted of disaccharide repeating units of D-glucose and sulfated and acetylated L-rhamnose established as →2)-α-L-Rhap3S4Ac-(1→6)-α-D-Glcp-(1→. To identify the genes responsible for CPS biosynthesis, whole-genome sequencing of KMM 8419 was carried out. Based on the genome annotations together with the Interproscan, UniProt and AntiSMASH results, a CPS-related gene cluster of 80 genes was found on chromosome 1. This cluster contained sets of genes encoding for the nucleotide sugar biosynthesis (UDP-Glc and dTDP-Rha), assembly (glycosyltransferases (GT)), transport (ABC transporter) and sulfation (PAPS biosynthesis and sulfotransferases) of the sulfated CPS. A hypothetical model for the assembly and transportation of the sulfated CPS was also proposed. In addition, this locus included genes for O-antigen biosynthesis. Further studies of biological activity, the structure–activity relationship in the new sulfated polysaccharide and its biosynthesis are necessary for the development of potent anticancer agents or drug delivery systems. Full article