bims-supasi 2026-04-12 papers

bims-supasi

Biomed News

on Sulfation pathways and signalling

Issue of 2026–04–12
twelve papers selected by
Jonathan Wolf Mueller, University of Birmingham

A Novel Chondroitinase AC from the Marine Bacterium Vibrio sp. ZLC12: Biochemical Characterization, Degradation Pattern, and Products Properties.
Heparin microarray-based specific interaction assay of marine sulfated polysaccharides with antithrombin Ⅲ.
Expression Optimization and Semirational Engineering of Ga6OST1 for Improved Catalytic Performance in Heparin Biosynthesis.
Novel SOAT inhibitors block DHEAS transport and suppress proliferation in MCF-7 breast cancer cells.
Cerebrospinal fluid heparan sulfate as a biomarker for neuronopathic mucopolysaccharidoses: Rationale and regulatory challenges.
MESH1 functions as a metazoan PAPS phosphatase to regulate sulfation.
Association between serum dehydroepiandrosterone sulfate and type 2 diabetes in US adults with adiposity as a mediator.
Time-dependent histological characterization of amyloid-β induced cholinergic and glial alterations and their modulation by dehydroepiandrosterone sulfate (DHEAS).
EFN-4/Ephrin converges with SAX-3/Robo, UNC-6/Netrin, and Heparan Sulfate Proteoglycan signaling to control MAB-5/Hox-dependent posterior Q neuroblast migration in Caenorhabditis elegans.
Chondroitin sulfate in osteoarthritis treatment: a twenty-year bibliometric analysis and comprehensive review.
A sulfated pectin polysaccharide from Chrysanthemum morifolium induces ferroptosis in pancreatic cancer by stabilizing TFRC.
Sulfonated Hyaluronic Acid-Based Polymers and Hydrogels Using Thiol-Ene and Thiol-Michael Reactions.

Biochimie. 2026 Apr 08. pii: S0300-9084(26)00084-2. [Epub ahead of print]

A Novel Chondroitinase AC from the Marine Bacterium Vibrio sp. ZLC12: Biochemical Characterization, Degradation Pattern, and Products Properties.

Wenwen Wang, Yuliang Xu, Yameng Zhu, Jinhua Zheng, Zeting Ning, Wule Gao, Xiaoyun Li, Guangcai Wang, Gaoshuo Zhang, Hongyan Qiu, Qingdong Zhang, Danrong Lu.

  Chondroitinases AC are vital for preparing chondroitin sulfate (CS) oligosaccharides and studying structure-activity relationships. In this study, a novel chondroitinase AC (ZL1) from marine Vibrio sp. ZLC12 was heterologously expressed in Escherichia coli, which showed optimal activity at 50°C and pH 7.0. The enzyme activities of ZL1 towards hyaluronic acid (HA), chondroitin sulfate A (CSA), chondroitin sulfate C (CSC), chondroitin sulfate D (CSD), and chondroitin sulfate E (CSE) were 1950±530, 2150±170, 1350±300, 1600±110, and 863±67 U/mg, respectively. As an endolyase, ZL1 can completely degrade HA and CSA into disaccharides, while generate small amounts of resistant tetrasaccharides when degrading CSC, CSD, and CSE. ZL1 is capable of cleaving 2-aminobenzamide (2-AB)-labelled CS disaccharides including O unit [-4 GlcA β1-3 GalNAc 1-], A unit [-4 GlcA β1-3 GalNAc(4S) 1-], C unit [-4 GlcA β1-3 GalNAc(6S) 1-], and partial D unit [-4 GlcA(2S) β1-3 GalNAc(6S) 1-] from the reducing end of 2-AB-labelled tetrasaccharides, except of 2-AB labeled E unit [-4 GlcA β1-3 GalNAc(4S, 6S) 1-]. The residues His283, Tyr292, Tyr288, and Lys656 are crucial for the enzyme activity and specific recognition of D unit-containing oligosaccharides. The discovery of ZL1 provides a highly valuable tool for the preparation and structural study of CS oligosaccharides.

Keywords:  PL8 family; Vibrio; chondroitin sulfate; chondroitinase

DOI:  https://doi.org/10.1016/j.biochi.2026.04.004
Commun Chem. 2026 Apr 07.

Heparin microarray-based specific interaction assay of marine sulfated polysaccharides with antithrombin Ⅲ.

Fei Wang, Qi Li, Han Zhou, Chanjuan Liu, Guangli Yu, Guoyun Li.

Marine sulfated polysaccharides (SPs) are promising candidates for new anticoagulant drug development, necessitating efficient method to evaluate their anticoagulant activity at the molecular level. In this work, a heparin microarray-based competitive strategy was developed to investigate the specific interactions between SPs and antithrombin Ⅲ (AT). The strategy is based on the principle that SPs competitively bind to the active domain of AT, reducing the signal of AT binding to immobilized heparin on microarrays. Validation was performed using established anticoagulants heparin and enoxaparin as model analytes. After optimizing key experimental conditions, the method successfully determined the IC50 values for three SPs: fucoidan derived from Ascophyllum nodosum (AnF, 50.55 ± 2.79 μg‧mL-1), fucosylated chondroitin sulfate derived from Holothuria tubulosa (FCSht, 44.18 ± 4.05 μg‧mL-1), and its selectively degraded sulfation product (S-dFCSht, 16.99 ± 6.56 μg‧mL-1). The reliability of these results was confirmed by surface plasmon resonance assay. The strategy's versatility was further demonstrated by assessing SP interactions with side effect-related proteins, providing valuable insights into both efficacy and safety profiles. Although currently applicable primarily to heparin-interacting anticoagulant targets, this strategy can be extended to other targets by fabricating specialized glycan microarrays, enabling comprehensive evaluation of SP interactions with various anticoagulant targets.

DOI: https://doi.org/10.1038/s42004-026-01999-4
ACS Synth Biol. 2026 Apr 10.

Expression Optimization and Semirational Engineering of Ga6OST1 for Improved Catalytic Performance in Heparin Biosynthesis.

Xinjing Wang, Yaxin Yu, Ping Dong, Daoan Wang, Ruirui Xu, Guocheng Du, Xintong Xi, Zhen Kang.

  Bioengineered heparin represents a safe and sustainable alternative to animal-derived anticoagulants. However, inefficient 6-O-sulfation catalyzed by heparan sulfate 6-O-sulfotransferase remains a bottleneck hindering the synthesis of heparin. Here, we establish a high-efficiency expression platform for Gallus gallus heparan sulfate 6-O-sulfotransferase 1 (Ga6OST1) in Komagataella phaffii. First, a systematic secretion-engineering strategy established an optimized production chassis with markedly elevated extracellular Ga6OST1 activity. Building on this platform, a semirational design strategy integrating structural modeling, evolutionary analysis, and hotspot prediction identified a triple mutant (MBP-Ga6OST1-A77R/V107L/V248T) with markedly improved properties. This variant exhibited a 2.4-fold increase in specific activity, a 2.3-fold enhancement in catalytic turnover, and a 5.3-fold extension in half-life at 37 °C. Structural analysis and molecular dynamics simulations revealed that cooperative reinforcement of hydrophobic packing and electrostatic networks underlies the observed gains in stability and catalytic durability. Under preparative catalytic conditions, the engineered enzyme displayed enhanced performance toward distinct sulfated heparin precursors, enabling the production of a final product with a 6-O-sulfation degree of 75.7%, comparable to that of porcine intestinal heparin. This work establishes an efficient platform for the production of structurally defined, highly 6-O-sulfated heparin and related derivatives.

Keywords:  Komagataella phaffii; enzyme stability; heparan sulfate 6-O-sulfotransferase; heparin; secretion optimization; semirational design

DOI:  https://doi.org/10.1021/acssynbio.6c00237
Sci Rep. 2026 Apr 10. pii: 12016. [Epub ahead of print]16(1):

Novel SOAT inhibitors block DHEAS transport and suppress proliferation in MCF-7 breast cancer cells.

Emre Karakus, Silke Leiting, Michael Daude, Wibke E Diederich, Joachim Geyer.

  Intracrine estrogen formation from adrenal precursors such as dehydroepiandrosterone sulfate (DHEAS) plays a critical role in sustaining estrogen receptor (ER)-positive breast cancer cell proliferation, particularly in postmenopausal women. The sodium-dependent organic anion transporter (SOAT, gene symbol SLC10A6) facilitates the cellular uptake of sulfated steroids, thereby making these precursors available for local estrogen biosynthesis. However, the impact of SOAT inhibition on intracrine estrogen metabolism in breast cancer remains unclear. We investigated the effects of pharmacological SOAT inhibition on SOAT-mediated DHEAS transport, cell proliferation and intracrine estradiol synthesis in SOAT-overexpressing MCF-7 breast cancer cells (MCF-7_SOAT). These MCF-7_SOAT cells were treated with the SOAT inhibitor S1647, as well as two newly synthesized derivatives (compounds 12 and 24) that exhibit enhanced selectivity and potency. DHEAS uptake and downstream steroid metabolism were quantified using LC-MS/MS, while DHEAS-induced cell proliferation was analyzed using [³H]thymidine incorporation. SOAT inhibition markedly reduced sodium-dependent DHEAS uptake, resulting in decreased intracellular estradiol synthesis and suppression of estrogen-dependent proliferation without cytotoxicity. These findings confirm that SOAT is a critical upstream regulator of intracrine estrogen biosynthesis in breast cancer cells and highlight compounds 12 and 24 as promising candidates for further preclinical development aimed at reducing local estrogen production.

Keywords:  Breast cancer; DHEAS transport; Endocrine therapy; Intracrine estrogen formation; MCF-7 cells; SOAT (SLC10A6)

DOI:  https://doi.org/10.1038/s41598-026-47803-0
Mol Genet Metab. 2026 Mar 31. pii: S1096-7192(26)00194-0. [Epub ahead of print]148(2): 109911

Cerebrospinal fluid heparan sulfate as a biomarker for neuronopathic mucopolysaccharidoses: Rationale and regulatory challenges.

Joseph Muenzer, Mark Dant, Patricia I Dickson, N Matthew Ellinwood, Maria Fuller, Roberto Giugliani, Kim Hemsley, Simon Jones, Terri Klein, Christina Lampe, John Mitchell, Nicole Muschol, Cara O'Neill, Torayuki Okuyama, Maurizio Scarpa, Fiona Stewart, Bob Stevens, Kim Stephens.

  Mucopolysaccharidoses (MPS) are a group of rare genetic disorders in which a deficiency of specific lysosomal enzymes results in abnormal glycosaminoglycans (GAG) catabolism. The biochemistry of MPS is well understood, and the primary event is a defect in GAG metabolism, leading to intralysosomal substrate accumulation and secondary lysosomal dysfunction. The MPS are heterogeneous disorders with physical and/or neurologic involvement with unmet medical needs. The severe or neuronopathic forms of MPS I (Hurler syndrome), MPS II (Hunter syndrome), MPS VII (Sly syndrome), and all classical forms of MPS III (Sanfilippo syndrome A-D) will develop cognitive impairment. Individuals with MPS I, MPS II, and MPS VII have elevated dermatan sulfate (DS) and heparan sulfate (HS) in their urine, while individuals with MPS III only have elevated HS. The predominant GAG observed in cerebrospinal fluid (CSF) in all individuals with neuronopathic MPS (nMPS) is HS. CSF HS correlates with brain tissue HS in MPS animal models. Therefore, the reduction of CSF HS reflects a decrease in brain tissue HS. CSF HS disaccharides can be reliably measured using mass spectrometry. However, regulatory challenges persist in accepting HS as a biomarker. Traditional trial designs with randomization are not feasible given the heterogeneity of nMPS and are unethical in a progressive neurodegenerative disease. Many countries have approval pathways using biomarkers, but they are underutilized. In summary, this review provides evidence supporting the use of CSF HS as a biomarker of treatment efficacy for the brain disease in individuals with nMPS.

Keywords:  Biomarker; CSF heparan sulfate; MPS; Neuronopathic MPS; Surrogate endpoint

DOI:  https://doi.org/10.1016/j.ymgme.2026.109911
Nat Chem Biol. 2026 Apr 10.

MESH1 functions as a metazoan PAPS phosphatase to regulate sulfation.

Chao-Chieh Lin, Joshua Rose, Albert Zhang, Anthony J Mirando, Alexander A Mestre, Chien-Kuang Cornelia Ding, Yihan Liao, Ssu-Yu Chen, Yasaman Setayeshpour, Jianli Wu, Zhong Li, Dong Yan, Matthew J Hilton, Pei Zhou, Jen-Tsan Chi.

Biological sulfation reactions require 3'-phosphoadenosine-5'-phosphosulfate (PAPS) as the universal sulfate donor. While the biosynthetic pathway of PAPS has been well characterized, the phosphatase degrading PAPS remains unidentified. Here, we discover MESH1 as a PAPS phosphatase that hydrolyzes PAPS into adenosine-5'-phosphosulfate and phosphate. Our crystallographic analysis of the MESH1-PAPS complex confirms PAPS as a bona fide substrate of MESH1. We further show that MESH1 localizes to Golgi, where sulfotransferases consume PAPS to produce sulfated glycosaminoglycan (sGAG). We show that MESH1 (also known as HDDC3) knockdown enhances sGAG production in a chondrogenic cell line. Furthermore, in brachymorphic mice, Mesh1 knockout significantly elevates sGAG levels in joint cartilage and improves bone density. In Caenorhabditis elegans lacking bpnt-1, neurotoxic PAP accumulation is alleviated by MESH1 overexpression, reducing upstream PAPS levels. Our biochemical, structural and functional findings establish MESH1 as a key PAPS phosphatase and highlights its potential as a therapeutic target in disorders characterized by sulfation deficiency.

DOI: https://doi.org/10.1038/s41589-026-02190-5
Medicine (Baltimore). 2026 Apr 10. 105(15): e48280

Association between serum dehydroepiandrosterone sulfate and type 2 diabetes in US adults with adiposity as a mediator.

Min Wu, Xiaohao Hu, Langhu Chen, Zhenzhong Zeng, Lianhui Chen.

  Dehydroepiandrosterone sulfate (DHEAS) is the most abundant adrenal androgen in circulation, yet its relationship with type 2 diabetes mellitus (T2DM) and the mediating role of adiposity remain unclear. We analyzed data from 4707 US adults (584 with T2DM, 4123 without diabetes) in the National Health and Nutrition Examination Survey 2021-2023. Serum DHEAS was quantified by isotope dilution LC-MS/MS. Survey-weighted logistic regression assessed the association between DHEAS and T2DM, adjusting sequentially for demographics, sex hormones, and measures of adiposity (body mass index, waist circumference, waist-to-hip ratio, and body roundness index). Restricted cubic splines tested for nonlinear relationships. Mediation analysis quantified the proportion of the DHEAS-T2DM association explained by adiposity. Median serum DHEAS was significantly lower in T2DM than in nondiabetic participants (1.28 vs 2.65 µmol/L; P < .001). Higher DHEAS was associated with reduced odds of T2DM after adjustment for demographics, hormones, and body mass index (per 1 µmol/L: odds ratio 0.87, 95% confidence interval 0.78-0.97). Individuals in the highest DHEAS quartile had lower T2DM odds compared with the lowest quartile (odds ratio 0.44, 95% confidence interval 0.20-0.99). Sex-stratified analysis showed a robust inverse association in men, but not in women. Restricted cubic splines analysis revealed a nonlinear, threshold effect, notably in men. Mediation analysis indicated that adiposity explained 14.4% to 21.8% of the inverse association. In a nationally representative US sample, higher serum DHEAS was independently associated with lower odds of T2DM, particularly among men, with partial mediation by adiposity, highlighting both adiposity-dependent and independent pathways.

Keywords:  NHANES; Type 2 diabetes; body mass index; dehydroepiandrosterone sulfate; obesity

DOI:  https://doi.org/10.1097/MD.0000000000048280
Front Endocrinol (Lausanne). 2026 ;17 1764298

Time-dependent histological characterization of amyloid-β induced cholinergic and glial alterations and their modulation by dehydroepiandrosterone sulfate (DHEAS).

Csenge Sólyomvári, Géza Makkai, Nicolas Capelo-Carrasco, Dubravka Svob Strac, Dóra Zelena, Szidónia Farkas.

   Introduction: Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder characterized by predominant - but not exclusive - pathological accumulation of amyloid-β (Aβ) in the brain. This process affects not only neurons (particularly cholinergic) but also glial cells, contributing to progressive neuronal loss and neuroinflammation. Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) are endogenous steroids that are hypothesized to exert neuroprotective and anti-inflammatory effects. This study aims to histologically characterize the in vivo temporal progression of Aβ-induced alterations in cholinergic neurons and glial morphology. Our secondary aim was to evaluate whether DHEAS protects cholinergic integrity and, if so, whether this effect is mediated through glial activation.
Methods: Aβ1-42 was injected into the cholinergic nucleus basalis magnocellularis (NBM) region of C57BL6/J male mice and one hour later 10 mg/kg DHEAS or vehicle (0.9% saline) was applied intraperitoneally. After 3, 12 or 33 days, the mice were transcardially perfused and immunohistochemical staining was used to investigate cholinergic cell (ChAT) and fiber (AChE) loss, as well as microglia (IBA1) and astrocyte (GFAP) morphology.
Results: Our findings confirmed that Aβ peptide exerted neurotoxic effects on the cholinergic system and triggered time-dependent activation in both glia cell types. Microglial cells initiated their response by day 3, adopting an amoeboid morphology, whereas delayed astrocytic reactivity was observed between days 3 and 12, demonstrated by increased ramification. DHEAS treatment preserved cholinergic fiber density, without effecting the number of cell bodies and modulated the inflammatory responses of glia cells, by decreasing the area occupied and number of microglia in a time dependent manner.
Discussion: Aβ toxicity exerts time-dependent effects on both cholinergic neurons and glia cells, while DHEAS shows therapeutic promise, though its efficacy and exact mechanism require further investigation.

Keywords:  amyloid-β; astrocytes; cholinergic system; dehydroepiandrosterone sulfate (DHEAS); microglia; neuroinflammation; neurosteroids

DOI:  https://doi.org/10.3389/fendo.2026.1764298
bioRxiv. 2026 Mar 31. pii: 2026.03.27.714887. [Epub ahead of print]

EFN-4/Ephrin converges with SAX-3/Robo, UNC-6/Netrin, and Heparan Sulfate Proteoglycan signaling to control MAB-5/Hox-dependent posterior Q neuroblast migration in Caenorhabditis elegans.

Vedant D Jain, Andrew M Johannesen, Felipe L Teixeira, Erik A Lundquist.

Hox genes have been broadly implicated in nervous system development, but the molecular and genetic mechanisms that act downstream of Hox factors remain to be identified. The MAB-5 antennapedia-like Hox transcription factor is both necessary and sufficient to cause posterior migration of the Q neuroblast descendants in Caenorhabditis elegans . In response to MAB-5, the left-side QL descendants QL.a and QL.ap undergo a three-stage migration process, with each stage characterized by a posterior lamellipodial protrusion followed by cell body migration. The QL.ap cell differentiates into the PQR neuron posterior to the anus. Previous studies showed that the MAB-5-regulated gene efn-4/Ephrin was required for the third and final stage of QL.ap migration, with efn-4 mutation resulting in placement of PQR immediately anterior to the anus. This subtle and previously-undescribed phenotype opens the possibility that other known neuronal development genes could be involved. In this work, we screened known signaling mutants for third-stage PQR migration defects. We found that mutations in SAX-3/Robo signaling, UNC-6/Netrin signaling, and heparan sulfate proteoglycans (HSPGs) all displayed third-stage PQR migration defects. The effects in single mutants were weak compared to efn-4 , and double mutant analysis revealed lack of genetic synergy, consistent with all of these molecules converging on a common pathway. This genetic analysis is consistent with physical interaction studies in vitro from another group that suggest that these molecules form connected communities of interacting extracellular domains, raising the possibility that they are all components of a large extracellular signaling complex required for posterior QL.ap migration. In this model, we envision that MAB-5/Hox drives EFN-4/Ephrin expression in QL.ap, which then seeds the formation of an extracellular signaling complex containing SAX-3/Robo signaling, UNC-6/Netrin signaling, and HSPGs that drives posterior lamellipodial formation and posterior migration.

DOI: https://doi.org/10.64898/2026.03.27.714887
J Mater Chem B. 2026 Apr 07.

Chondroitin sulfate in osteoarthritis treatment: a twenty-year bibliometric analysis and comprehensive review.

Ainikaer Abulaiti, Zhen Liu, Shi Qiu, Maihemuti Yakufu, Paerhati Wahafu, Maerdan Maimaitiming, Jiashun Li, Zheng Wang, Yaqin An, Munisha Abulikemu, Kaishaer Baihetiyaer, Deyu Li, Li Shu, Guohua Li, Yuxiang Zhang.

This study employs bibliometric methods to systematically analyze the research trajectory and frontier trends in the application of chondroitin sulfate (CS) for the treatment of osteoarthritis (OA) from 2005 to 2025. Through a visual analysis of 2004 relevant articles from the Web of Science core collection, the field is revealed to have evolved through three distinct stages: from early pharmacological treatment and fundamental research, to the integration of tissue engineering and biomaterials, culminating in the current focus on intelligent therapeutic strategies centered on precision drug delivery systems. The findings indicate a global research landscape characterized by a "dual-core dominance of China and the United States." While China leads in publication output, its academic influence, as measured by citation metrics, lags behind that of European and American countries. Keyword analysis identifies "inflammation" and "drug delivery systems" as recent research hotspots, with targeted delivery systems based on biomaterials such as hydrogels and nanoparticles emerging as the technological frontier. The study also highlights persistent challenges in the clinical translation of CS, including issues related to delivery efficiency, material properties, large-scale manufacturing, and interdisciplinary collaboration. Looking forward, by integrating smart responsive materials, multimodal synergistic therapies, and strengthening international cooperation, CS-based strategies show promise in shifting the OA treatment paradigm from symptomatic relief to structural repair. By bridging macro-level literature analysis with micro-level materials chemistry insights, this work provides a comprehensive framework that integrates quantitative research mapping with mechanistic understanding of CS-based biomaterial design. This dual perspective aims to inform not only research planning and translational pathways, but also the rational design of CS derivatives with tailored physicochemical properties for specific OA therapeutic applications.

DOI: https://doi.org/10.1039/d6tb00057f
Carbohydr Polym. 2026 Jun 01. pii: S0144-8617(26)00341-3. [Epub ahead of print]381 125224

A sulfated pectin polysaccharide from Chrysanthemum morifolium induces ferroptosis in pancreatic cancer by stabilizing TFRC.

Zixuan Wang, Youning Jiang, Yilin Wang, Shengjie Wu, Shiying Zhang, Can Jin, Fei He, Kan Ding.

  Pancreatic ductal adenocarcinoma (PDAC) is the most malignant tumor with dismal prognosis. The chemotherapy effect of PDAC is limited and has severe side effects. Hence, identifying a natural leading compound with high efficacy against PDAC is urgently needed. Chrysanthemum morifolium (C. morifolium), a traditional Chinese medicinal herb with reported antitumor properties, was hypothesized to contain polysaccharides with therapeutic efficacy against PDAC. A novel homogeneous RG-I pectin, HJ222, was successfully isolated and purified. Structural analysis shows that HJ222 possesses a backbone composed of repeating →2-α-Rhap-(1 → 4)-α-GalpA-(1 → units, with side chains extending from the O-4 position of 2,4-α-Rhap and certain 3,4-α-GalpA residues, forming galactose- and arabinose-rich branches. In vitro and in vivo assays demonstrate that the sulfated derivative S3HJ222 of HJ222 can significantly suppress pancreatic cancer cell proliferation and completely retard tumor growth in patient-derived xenograft mouse models. Mechanistic studies reveal that S3HJ222 can induce ferroptosis-a non-apoptotic form of cell death-by elevating intracellular Fe2+ and reactive oxygen species (ROS). Furthermore, S3HJ222 directly binds and stabilizes transferrin receptor (TFRC), and activates the acyl-CoA synthetase long-chain family member 4 (ACSL4) signaling axis. Collectively, S3HJ222 may be a promising active compound for the development of new anti-PDAC drugs.

Keywords:  Anti-pancreatic cancer; Chrysanthemum morifolium; Polysaccharide; Sulfated derivatives; ferroptosis

DOI:  https://doi.org/10.1016/j.carbpol.2026.125224
Macromol Biosci. 2026 Apr;26(4): e00319

Sulfonated Hyaluronic Acid-Based Polymers and Hydrogels Using Thiol-Ene and Thiol-Michael Reactions.

Ivo Anton Octave Beeren, Pieter Jelle Dijkstra, Ane Albillos Sanchez, Jopeth Ramis, Francesca Perin, Carlos Mota, Sandra Camarero-Espinosa, Lorenzo Moroni, Matthew Brandon Baker.

  Non-sulfated polysaccharides like hyaluronic acid (HA) have been widely studied as scaffold material for tissue engineering applications. To mimic the function of sulfated glycosaminoglycan in the matrix, sulfate groups can be grafted. However, here, harsh reaction conditions are required which induce significant backbone degradation. As an alternative, sulfonates (R-SO3 -) have been shown to resemble the function of sulfates yet have not been introduced on polysaccharides. Using a two-step strategy, we introduced a tunable amount of sulfonate groups on HA, without requiring harsh reaction conditions and organic solvents. By varying the degree of carboxylic acid activation using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM), norbornene (NB, 3-18%) or maleimide (MAL, 2-14%) groups were grafted. Subsequently, 3-mercapto-1-propanesulfonate was coupled in high efficiency on the addressable groups via orthogonal thiol-ene and thiol-Michael addition. Additionally, we demonstrated the formation of hydrogels using poly(ethylene glycol)-di-SH as a crosslinker. However, because of the low crosslinking kinetics, HA-MAL appeared not useful for application. Simultaneous addition of the crosslinker and MPS to norbornyl-conjugated HA's in various ratios enabled the formation of hydrogels with tunable stiffness and degree of sulfonate groups. The simple strategy is likely applicable to other commonly used polysaccharides and therefore interesting to the broader tissue engineering community.

Keywords:  carboxylic acid activation; hyaluronic acid; sulfonated hydrogels; sulfonation

DOI:  https://doi.org/10.1002/mabi.202500319