Hyaluronan Synthase Research Articles

Wheat Ceramide Powder Mitigates Ultraviolet B-Induced Oxidative Stress and Photoaging by Inhibiting Collagen Proteolysis and Promoting Collagen Synthesis in Hairless Mice.

The protective effects of wheat ceramide powder (WC-P) on ultraviolet B (UVB)-induced skin oxidative stress and photoaging in hairless mice were investigated in this study. Moreover, the activities of antioxidant enzymes, inflammation, wrinkle formation-related pathway, and moisturizing capacity were evaluated. Mice were randomly divided into six groups (n=8): normal control (non-UVB irradiation), control (UVB irradiation), L-ascorbic acid [positive control, UVB irradiation with dietary supplementation of L-ascorbic acid at 100 mg/kg/body weight (bw)], WC-P5 (UVB irradiation with dietary supplementation of WC-P at 5 mg/kg/bw), WC-P20 (UVB irradiation with dietary supplementation of WC-P at 20 mg/kg/bw), and WC-P40 (UVB irradiation with dietary supplementation of WC-P at 40 mg/kg/bw). AIN-96G diet and water were supplemented ad libitum, and 100 mL of L-ascorbic acid and WC-P dissolved in water were forcefully administered orally to mice. UVB irradiation resulted in dehydration and wrinkle formation in the dorsal skin of mice. However, WC-P supplementation suppressed. Furthermore, WC-P supplementation enhanced the activites of antioxidant enzymes and expression of transforming growth factor-β receptor I, procollaten C-endopeptideas enhancer protein, hyaluronan synthase, and ceramide synthase 4 and reduced the activation of the inflammation and the c-Jun N-terminal kinase/c-FOS/c-Jun- mediated matrix metalloproteinase pathways. These findings demonstrate that WC-P can protect the skin from UVB-induced oxidative stress, inflammation, and photoaging by inhibiting collagen proteolysis and promoting collagen synthesis, thereby promoting skin health.

Skin Anti-Aging Efficacy of Enzyme-Treated Supercritical Caviar Extract: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

Oxidative stress in the skin, induced by an unhealthy lifestyle and exposure to UVB radiation, leads to skin aging, including reduced elasticity, formation of wrinkles, moisture loss, and inflammation. In a previous study, we revealed the photoaging effects of enzyme-treated caviar extract (CV) by regulating collagen and hyaluronic acid synthase, melanogenesis, anti-oxidant mechanisms, and inflammation in a UVB irradiation-induced mice model. HPLC and MALDI-TOF were performed to determine the effect of enzyme treatment on the free amino acid contents and peptide molecular weight in supercritical caviar extract. As results of the analysis, CV is mainly composed of low-molecular-weight peptides consisting of leucine, tyrosine, and phenylalanine. Based on our in vitro and in vivo study, we conducted a clinical trial to assess the skin anti-aging efficacy of CV. In this randomized, double-blind, placebo-controlled trial, we measured indicators related to elasticity, wrinkles, and skin hydration at 4 and 8 weeks after consumption of CV. The subjects were categorized into caviar, combination, and placebo groups. After 4 weeks, skin hydration, dermal hydration, and transepidermal water loss all showed significant improvement. Furthermore, after 8 weeks, skin elasticity indexes-R2 (total elasticity), R5 (net elasticity), and R7 (ratio of elastic recovery to total deformation)-exhibited significant increases. Improvement in wrinkle indicators (Rmax, Ra, and Rz) and the whitening indicator melanin pigment was also observed. This is the first report showing that CV has significant skin anti-aging efficacy on human skin. In conclusion, our study suggests that CV can be used as skin anti-aging nutraceuticals through positive effects on skin condition in clinical trials.

Hyaluronan delays human amniotic epithelial stem cell senescence by regulating CD44 isoform switch to activate AKT/mTOR signals

The replicative senescence of human amniotic epithelial stem cells (hAECs) is a major concern towards its clinical application. This study found that a 300-kDa hyaluronic acid (HA) could effectively delay the replicative senescence of hAECs, as indicated by the downregulation of cellular senescence markers and alteration of the cell cycle, and substantially improve the differentiation capacities of hAECs. HA was confirmed to regulate the CD44 isoform switch by upregulating the CD44s and downregulating the CD44v, thus exerting an anti-aging effect. We further found that HA induced the upregulation of hyaluronan synthase (HAS) 2, resulting in the activation of epithelial splicing regulatory protein 1 (ESRP1) and alternative splicing of CD44 mRNA, thereby promoting CD44s expression and inhibiting CD44v expression. Knockdown of HAS2 blocked ESRP1 expression and attenuated the anti-aging effects of HA. Hermes-1, a specific blocker of CD44, caused partial loss of the anti-aging effect of HA, upregulated senescence markers, and downregulated stemness markers. Furthermore, CD44s receptor activation was shown to initiate the AKT/mTOR downstream signaling. Conclusively, the study suggested that HA delayed hAEC senescence by regulating CD44 isoform switch to activate the AKT/mTOR signaling pathway, and there is potential for the clinical application of hAECs in combination with HA.

Naked mole-rat hyaluronan

Naked mole rats (NMRs) are renowned for their exceptional longevity and remarkable maintenance of health throughout their lifetime. Their subterranean lifestyle has led to adaptations that have resulted in elevated levels of a very high molecular weight hyaluronan in their tissues. Hyaluronan, a glycosaminoglycan, is a key component of the extracellular matrix, which plays a critical role in maintaining tissue structure and regulating cell signaling pathways. This phenomenon in NMRs is attributed to a higher processing and production capacity by some of their hyaluronan synthases, along with lower degradation by certain hyaluronidases. Furthermore, this adaptation indirectly confers several advantages to NMRs, such as the preservation of skin elasticity and youthful appearance, accelerated wound healing, protection against oxidative stress, and resistance to conditions such as cancer and arthritis, largely attributable to CD44 signaling and other intricate mechanisms. Thus, the main objective of this study was to conduct a comprehensive study of the distinctive features of NMR hyaluronan, particularly emphasizing the currently known molecular mechanisms that contribute to its beneficial properties. Furthermore, this research delves into the potential applications of NMR hyaluronan in both cosmetic and therapeutic fields, as well as the challenges involved.

A role for decorin in improving motor deficits after traumatic brain injury

Traumatic brain injury (TBI) is the leading cause of death and disability due to injury worldwide. Extracellular matrix (ECM) remodeling is known to significantly contribute to TBI pathophysiology. Glycosaminoglycans, which are long-chain, variably sulfated polysaccharides abundant within the ECM, have previously been shown to be substantially altered after TBI. In this study, we sought to delineate the dynamics of glycosaminoglycan alterations after TBI and discover the precise biologic processes responsible for observed glycosaminoglycan changes after injury. We performed state-of-the art mass spectrometry on brain tissues isolated from mice after TBI or craniotomy-alone. We observed dynamic changes in glycosaminoglycans at Day 1 and 7 post-TBI, with heparan sulfate, chondroitin sulfate, and hyaluronan remaining significantly increased after a week vis-à-vis craniotomy-alone tissues. We did not observe appreciable changes in circulating glycosaminoglycans in mice after experimental TBI compared to craniotomy-alone nor in patients with TBI and severe polytrauma compared to control patients with mild injuries, suggesting increases in injury site glycosaminoglycans are driven by local synthesis. We subsequently performed an unbiased whole genome transcriptomics analysis on mouse brain tissues 7 days post-TBI and discovered a significant induction of hyaluronan synthase 2, glypican-3, and decorin. The functional role of decorin after injury was further examined through multimodal behavioral testing comparing wild-type and Dcn−/− mice. We discovered that genetic ablation of Dcn led to an overall negative effect of TBI on function, exacerbating motor impairments after TBI. Collectively, our results provide a spatiotemporal characterization of post-TBI glycosaminoglycan alterations in the brain ECM and support an important adaptive role for decorin upregulation after TBI.

Targeting Hyaluronan Synthesis in Cancer: A Road Less Travelled

Hyaluronan is one of the major components of the extracellular matrix and is involved in the regulation of multiple processes in both human physiology and disease. In human cancers, hyaluronan metabolism displays remarkable alterations, leading to the accumulation of large amounts of hyaluronan matrices in the tumoural tissues. The altered levels of hyaluronan in the tumours stem from the enhanced expression and activity of hyaluronan synthases in both tumour and stromal cells. Moreover, hyaluronidase activity is also upregulated in cancer, leading to the generation of lower molecular weight hyaluronan fragments that in turn assist tumour growth, neo-angiogenesis and the metastatic cascade. Hyaluronan accumulation in malignant tissues not only assists tumour growth and metastases but is also associated with worse outcomes in cancer patients. Therefore, targeting hyaluronan synthesis emerges as an interesting strategy that might be employed for cancer treatment. This review article summarises current evidence and discusses ways to move forward in the field of targeting hyaluronan synthesis for cancer therapy.

Liver-Targeting Composite Nanocarrier Delivery System Based on Chitosan Nanoparticles and Phospholipid Complexes.

Liver fibrosis is mainly caused by excessive accumulation of extracellular matrix and structural changes in the liver, ultimately leading to cirrhosis if left untreated. Reducing hyaluronan synthesis by inhibiting hyaluronic acid deposition or regulating the expression of hyaluronic synthase can ameliorate liver fibrosis symptoms. In this study, we aimed to improve the bioavailability and liver-targeting capacity of hydroxymethyl coumarin (4-MU) using a newly developed phospholipid complex chitosan nanoparticle (4-MU PC/CNP) optimized using the Box-Behnken design. The composite nanocarrier delivery system was formulated using solvent evaporation technology, and formulation and process parameters were evaluated. Furthermore, 4-MU PC/CNPs and their pharmacokinetics were characterized. The established 4-MU PC/CNPs had an average particle size of 153.07 ± 0.29 nm, a polydispersity index value of 0.383, and a positive zeta potential of ∼35.4 mV. Compared with 4-MUs, 4-MU PC/CNPs exhibited significantly improved water solubility, faster plasma clearance and tissue distribution, and better liver targeting. Pharmacokinetic analysis showed that the oral bioavailability of 4-MU in 4-MU PC/CNPs was significantly higher than that of simple 4-MU. In conclusion, 4-MU PC improved drug lipid (oil-water distribution coefficient of 1.31 ± 0.03) and water solubilities (2.05 times the drug substance). 4-MU PC/CNPs significantly improved 4-MU oral bioavailability, representing a promising approach for enhancing drug solubility. This study demonstrates that the targeting parameters of 4-MU PC/CNPs in the liver were all greater than 1, indicating that they specifically targeted the liver, thereby potentially alleviating liver fibrosis.

Exosomes derived from human dermal fibroblasts (HDFn-Ex) alleviate DNCB-induced atopic dermatitis (AD) via PPARα.

Atopic dermatitis (AD) is a chronic inflammatory skin disease. Skin barrier dysfunction is the initial step in the development of AD. Recently, exosomes have been considered as potential cell-free medicine for skin defects such as aging, psoriasis and wounds. The aim of this study was to investigate the effects of human dermal fibroblast-neonatal-derived exosome (HDFn-Ex) on AD. HDFn-Ex increased the expression of peroxisome proliferator activated receptor α (PPARα) and alleviated the 1-chloro-2,4-dinitrobenzene (DNCB)-mediated downregulation of filaggrin, involucrin, loricrin, hyaluronic acid synthase 1 (HAS1) and HAS2 in human keratinocyte HaCaT cells. However, these effects were inhibited by the PPARα antagonist GW6471. In the artificial skin model, HDFn-Ex significantly inhibited DNCB-induced epidermal hyperplasia and the decrease in filaggrin and HAS1 levels via a PPARα. In the DNCB-induced AD-like mouse model, HDFn-Ex administration reduced epidermis thickening and mast cell infiltration into the dermis compared to DNCB treatment. Moreover, the decreases in PPARα, filaggrin and HAS1 expression, as well as the increases in IgE and IL4 levels induced by DNCB treatment were reversed by HDFn-Ex. These effects were blocked by pre-treatment with GW6471. Furthermore, HDFn-Ex exhibited an anti-inflammatory effect by inhibiting the DNCB-induced increases in IκBα phosphorylation and TNF-α expression. Collectively, HDFn-Ex exhibited a protective effect on AD. Notably, these effects were regulated by PPARα. Based on our results, we suggest that HDFn-Ex is a potential candidate for treating AD by recovering skin barrier dysfunction and exhibiting anti-inflammatory activity.

Age related changes in hyaluronan expression leads to Meibomian gland dysfunction

The prevalence of dry eye disease (DED) ranges from ∼5 to 50 % and its associated symptoms decrease productivity and reduce the quality of life. Approximately 85 % of all DED cases are caused by Meibomian gland dysfunction (MGD). As humans and mice age, their Meibomian glands (MGs) undergo age-related changes resulting in age related-MGD (ARMGD). The precise cause of ARMGD remains elusive, which makes developing therapies extremely challenging. We previously demonstrated that a hyaluronan (HA)-rich matrix exists surrounding the MG, regulating MG morphogenesis and homeostasis. Herein, we investigated whether changes to the HA matrix in the MG throughout life contributes towards ARMGD, and whether altering this HA matrix can prevent ARMGD. For such, HA synthase (Has) knockout mice were aged and compared to age matched wild type (wt) mice. MG morphology, lipid production, PPARγ expression, basal cell proliferation, stem cells, presence of atrophic glands and MG dropout were analyzed at 8 weeks, 6 months, 1 year and 2 years of age and correlated with the composition of the HA matrix. We found that as mice age, there is a loss of HA expression in and surrounding the MGs of wt mice, while, in contrast, Has1−/−Has3−/− mice present a significant increase in HA expression through Has2 upregulation. At 1 year, Has1−/−Has3−/− mice present significantly enlarged MGs, compared to age-matched wt mice and compared to all adult mice. Thus, Has1−/−Has3−/− mice continue to develop new glandular tissue as they age, instead of suffering MG atrophy. At 2 years, Has1−/−Has3−/− mice continue to present significantly larger MGs compared to age-matched wt mice. Has1−/−Has3−/− mice present increased lipid production, increased PPARγ expression and an increase in the number of proliferating cells when compared to wt mice at all-time points analyzed. Taken together, our data shows that a loss of the HA matrix surrounding the MG as mice age contributes towards ARMGD, and increasing Has2 expression, and consequently HA levels, prevents ARMGD in mice.

Hyaluronan Synthase Contributes to Tubulointerstitial Fibrosis in a Murine Model of CKD

Hyaluronan Synthase Contributes to Tubulointerstitial Fibrosis in a Murine Model of CKD

Expression analysis of genes important for maintaining skin function in a senescence-accelerated mouse prone model.

Senescence-accelerated mouse prone (SAMP) mice can reproduce the same conditions as normal aging mice in a short period. Although SAMP mice have been widely used in aging research, research on skin function in SAMP mice is lacking. In this study, to investigate the skin function of SAMP mice, we analyzed the expression of genes important for maintaining skin function. Eight-month-old SAMP mice and senescence-accelerated mouse resistant (SAMR) mice with normal aging were used. The expression levels of various functional genes in the skin were analyzed. The dermal water content of SAMP mice was significantly lower than that of SAMR mice, indicating dry skin. The mRNA expression levels of elastin (Ela), filaggrin (Flg), loricrin (Lor), collagen type I alpha 1 chain (Col1a1) and Col1a2 in the skin of SAMP mice were all significantly decreased compared with those of SAMR mice. Hyaluronan-degrading enzyme (Hyal1) expression levels in SAMP mice were similar to those in SAMR mice, but hyaluronan synthase (Has2) levels were significantly decreased. In addition, the expression level of aquaporin-3 in the skin of SAMP mice was significantly decreased at both the mRNA and protein levels. In the skin of SAMP mice, the expression levels of various skin function-regulating genes were decreased, and this phenomenon might cause skin dryness. The SAMP mouse could be a tool for analyzing skin aging. Geriatr Gerontol Int 2023; 23: 951-957.

Attenuated Replication-Competent Herpes Simplex Virus Expressing an ECM-Modifying Transgene Hyaluronan Synthase 2 of Naked Mole Rat in Oncolytic Gene Therapy.

Herpes simplex virus (HSV) has proven successful in treating human cancer. Since the approval of talimogene laherparepvec (T-VEC) in 2015, HSV has been thoroughly researched to discover novel mechanisms to combat cancer and treat other diseases. Another HSV-based drug, beremagene geperpavec (B-VEC), received approval in 2023 to treat the rare genetic disease dystrophic epidermolysis bullosa, and was also the first clinically approved HSV vector carrying an extracellular matrix (ECM)-modifying transgene. The ECM is a network of macromolecules surrounding cells, which provides support and regulates cell growth and differentiation, the disruption of which is common in cancer. The naked mole rat (NMR) has a thick ECM and a unique mutation in the hyaluronan synthase 2 (HAS2) gene, which has been linked to the high cancer resistance of the species. To study the effect of this mutation in human cancer, we have developed an attenuated, replication-competent HSV vector expressing the NMR-HAS2 gene. The viral replication, transgene expression and cytotoxic effect of the novel vector was studied in glioma cells. Our results show that an attenuated, replication-competent HSV vector expressing a foreign ECM-modifying transgene, namely HAS2, provides an effective tool to study and combat cancer in humans.

The effect of L-carnitine on oocyte mitochondrial health and biomarkers on cyclophosphamide chemotherapy drug in mice

Improving oocyte competence during chemotherapy is widely known as a contributing factor to increasing the probability of fertility. Additionally, the role of cumulus cells in oocyte quality is of utmost importance. Therefore, this study was designed to simultaneously probe into the relative gene expression of oocytes and cumulus cells as biomarkers of oocyte quality with cyclophosphamide and L-carnitine treatment. A total of 60 adult NMRI mice were divided into four groups: control, L-carnitine (LC), cyclophosphamide (CP), and cyclophosphamide+L-carnitine (CP+LC). The relative mRNA expression levels of oocyte quality genes including growth differentiation factor 9 (Gdf9), hyaluronan synthase 2 (Has2), and mitochondrial sirtuin 3 (Sirt3) in oocytes, and genes involved in bilateral communication between cumulus cells and between the oocyte and its neighboring cumulus cells including connexin 37 (Cx37) and connexin 43 (Cx43) were detected by Real-time-PCR. DCFH-DA staining analyzed the level of intracellular ROS in oocytes. Under the influence of L-carnitine, Gdf9, Has2, Cx43, and Cx37 were significantly up-regulated (p ≤ 0.05). However, cyclophosphamide considerably reduced the expression of all these genes (p ≤ 0.05). The expression of the Sirt3 gene in the CP group increased significantly compared to the other groups (p ≤ 0.05). Analysis of fluorescent images revealed that the level of intracellular ROS in the cyclophosphamide group was significantly increased compared to the other groups (p ≤ 0.05), while it plummeted in the L-carnitine group (p ≤ 0.05). L-carnitine as an antioxidant can reduce the destructive effects of cyclophosphamide and enhance bilateral communications between oocytes and cumulus cells, and it may ultimately lead to an increase in the fertility rate.

Cotadutide improves brown adipose tissue thermogenesis in obese mice

We studied the effect of cotadutide, a dual agonist glucagon-like peptide 1 (GLP1)/Glucagon, on interscapular brown adipose tissue (iBAT) remodeling and thermogenesis of obese mice. Twelve-week-old male C57BL/6 mice were fed a control diet (C group, n = 20) or a high-fat diet (HF group, n = 20) for ten weeks. Then, animals were redivided, adding cotadutide treatment: C, CC, HF, and HFC for four additional weeks. The multilocular brown adipocyte structure showed fat conversion (whitening), hypertrophy, and structural disarray in the HF group, which was reverted in cotadutide-treated animals. Cotadutide enhances the body temperature, thermogenesis, and sympathetic innervation (peroxisome proliferator-activated receptor-α, β3 adrenergic receptor, interleukin 6, and uncoupled protein 1), reduces pro-inflammatory markers (disintegrin and metallopeptidase domain, morphogenetic protein 8a, and neuregulin 4), and improves angiogenesis (vascular endothelial growth factor A, and perlecan). In addition, cotadutide enhances lipolysis (perilipin and cell death-inducing DNA fragmentation factor α), mitochondrial biogenesis (nuclear respiratory factor 1, transcription factor A mitochondrial, mitochondrial dynamin-like GTPase, and peroxisome proliferator-activated receptor gamma coactivator 1α), and mitochondrial fusion/fission (dynamin-related protein 1, mitochondrial fission protein 1, and parkin RBR E3 ubiquitin protein ligase). Cotadutide reduces endoplasmic reticulum stress (activating transcription factor 4, C/EBP homologous protein, and growth arrest and DNA-damage inducible), and extracellular matrix markers (lysyl oxidase, collagen type I α1, collagen type VI α3, matrix metallopeptidases 2 and 9, and hyaluronan synthases 1 and 2). In conclusion, the experimental evidence is compelling in demonstrating cotadutide's thermogenic effect on obese mice's iBAT, contributing to unraveling its action mechanisms and the possible translational benefits.

The anti-inflammation and skin-moisturizing effects of Boehmeria tricuspis-mediated biosynthesized gold nanoparticles in human keratinocytes.

Introduction: Recently, nanotechnology has emerged as a potential technique for skin generation, which has several treatment advantages, such as decreased drug cytotoxicity and enhanced skin penetration. Boehmeria tricuspis (BT) belongs to the Urticaceae family and is rich in phenolic and flavonoid compounds. In this study, we biosynthesized gold nanoparticles (BT-AuNPs) using BT extract to explore their anti-inflammatory and skin-moisturizing properties in keratinocytes. Methods: Field-emission transmission electron microscopy, energydispersive X-ray spectrometry, dynamic light scattering, and Fourier-transforminfrared spectroscopy were used to examine the synthesized BT-AuNPs. qRT-PCR, western blot, and ELISA were applied for investigating the effect of BT-AuNPs on anti-inflammation and moisturizing activity in HaCaT cells. Results: At concentrations below 200 μg/mL, BT-AuNPs had no cytotoxic effect on keratinocytes. BT-AuNPs dramatically alleviated the expression and secretion of inflammatory chemokines/cytokine, such as IL-6, IL-8, TARC, CTACK, and RANTES in keratinocytes stimulated by tumor necrosis factor-α/interferon-γ (T + I). These anti-inflammatory properties of BT-AuNPs were regulated by inhibiting the NF-κB and MAPKs signaling pathways. Furthermore, BT-AuNPs greatly promoted hyaluronic acid (HA) production by enhancing the expression of hyaluronic acid synthase genes (HAS1, HAS2, and HAS3) and suppressing the expression of hyaluronidase genes (HYAL1 and HYAL2) in HaCaT cells. Discussion: These results suggest that BT-AuNPs can be used as a promising therapeutic alternative for treating skin inflammation. Our findings provide a potential platform for the use of BT-AuNPs as candidates for treating inflammatory skin diseases and promoting skin health.

Regenerative Effect of a 532-nm Diode Laser on Vocal Fold Scar in a Rabbit Model

We evaluated the regenerative effect of a 532-nm diode laser in a rabbit model of vocal fold scarring. This study included 40 male New Zealand white rabbits: 20 underwent vocal fold scar surgery only (control group) and 20 underwent 532-nm diode laser glottoplasty 1 month after vocal fold scar surgery (glottoplasty group). Histological and high-speed video analyses of vocal fold vibration were performed 1 month after vocal fold scar surgery and laser glottoplasty. The maximum amplitude of vocal fold vibration and dynamic glottal gap was measured. Real-time polymerase chain reaction (PCR) was also performed to evaluate scar regeneration and wound remodeling. Transforming growth factor (TGF)-ß1, interleukin (IL)-6, procollagen-1, matrix metalloproteinase (MMP)-2, MMP-9, hyaluronan synthase (HAS)-2, and HAS-3 levels were measured. The maximum difference in amplitude of vocal fold vibration and the dynamic glottal gap was significantly greater in the glottoplasty than in the control group. Real-time PCR revealed significantly higher MMP-2, MMP-9, HAS-2, and HAS-3 levels, and lower TGF-ß1, IL-6, and procollagen-1 level, in the glottoplasty than control group. The histological findings showed that the lamina propria (LP) ratio (LP pixels/total vocal fold pixels) was not significantly different between the two groups. Based on the vocal fold vibration and real-time PCR results, the 532-nm diode laser improved vocal fold vibration in a rabbit model of vocal fold scarring.

Selective adhesion inhibition and hyaluronan envelope reduction of dermal tumor cells by cold plasma-activated medium

ABSTRACT The sensitivity to cold plasma is specific to tumor cells while leaving normal tissue cells unaffected. This is the desired challenge in cancer therapy. Therefore, the focus of this work was a comparative study concerning the plasma sensitivity of dermal tumor cells (A-431) versus non-tumorigenic dermal cells (HaCaT) regarding their adhesion capacity. We found a selective inhibiting effect of plasma-activated medium on the adhesion of tumor cells while hardly affecting normal cells. We attributed this to a lower basal gene expression for the adhesion-relevant components CD44, hyaluronan synthase 2 (HAS2), HAS3, and the hyaluronidases in A431. Noteworthy, after plasma exposure, we revealed a significantly higher expression and synthesis of the hyaluronan envelope, the HAS3 gene, and the transmembrane adhesion receptors in non-tumorigenic HaCaTs.

Taurine accelerates the synthesis of ceramides and hyaluronic acid in cultured epidermis and dermal fibroblasts.

Taurine is a sulfur-containing amino acid derivative that can be found in the majority of mammalian tissues. Taurine is also present in the skin and is involved in maintaining skin homeostasis by exerting osmoregulatory and antioxidant effects. Previous studies have indicated that taurine treatment is effective against age-, ultraviolet- or detergent-induced skin dysfunction. To determine the mechanism responsible for the beneficial actions of taurine in the skin, the present study aimed to evaluate the effects of taurine on epidermal components (ceramides and filaggrin) and on the dermal extracellular matrix, in three-dimensionally (3D) cultured epidermis and dermal fibroblasts, respectively. These cells were cultured in the presence of 3-50 mM taurine, and cells or culture medium were collected for analysis. The effects of taurine on transepidermal water loss (TEWL) in the skin and the expression of inflammatory cytokines, including IL-1α, IL-1β and IL-1 receptor antagonist, were investigated in acetone-treated 3D-cultured epidermis using a Tewameter and reverse transcription-quantitative PCR (RT-qPCR), respectively. The mRNA expression levels of MMP-1 and hyaluronic acid (HA) production were measured in skin dermal fibroblasts using RT-qPCR and ELISA, respectively. Taurine was found to suppress acetone-induced elevation in TEWL in 3D-cultured epidermis. Taurine also stimulated the mRNA expression of ceramide synthase 4 and filaggrin, a major structural protein in the stratum corneum, in 3D-cultured epidermis. In skin dermal fibroblasts, taurine inhibited the IL-1α-stimulated mRNA and protein expression of MMP-1. In addition, taurine treatment increased HA synthase-2 mRNA expression and in turn HA production. Results from the present study suggest that the protective effect of taurine on the skin is associated with the enhancement of epidermal barrier component expression and modulation of dermal extracellular matrix metabolism.

Mesenchymal stromal cells confer breast cancer doxorubicin resistance by producing hyaluronan.

Chemotherapy resistance represents a major cause of therapeutic failure and mortality in cancer patients. Mesenchymal stromal cells (MSCs), an integral component of tumor microenvironment, are known to promote drug resistance. However, the detailed mechanisms remain to be elucidated. Here, we found that MSCs confer breast cancer resistance to doxorubicin by diminishing its intratumoral accumulation. Hyaluronan (HA), a major extracellular matrix (ECM) product of MSCs, was found to mediate the chemoresistant effect. The chemoresistant effect of MSCs was abrogated when hyaluronic acid synthase 2 (HAS2) was depleted or inhibited. Exogenous HA also protected tumor grafts from doxorubicin. Molecular dynamics simulation analysis indicates that HA can bind with doxorubicin, mainly via hydrophobic and hydrogen bonds, and thus reduce its entry into breast cancer cells. This mechanism is distinct from the reported chemoresistant effect of HA via its receptor on cell surface. High HA serum levels were also found to be positively associated with chemoresistance in breast cancer patients. Our findings indicate that the HA-doxorubicin binding dynamics can confer cancer cells chemoresistance. Reducing HA may enhance chemotherapy efficacy.

Self-assembly immobilization of a universal catalytic microreactor for glycosyltransferases

Hyaluronic acid (HA) and chondroitin sulfate (CS) are polydisperse glycosaminoglycans (GAGs),which have important applications as health care products and drugs in skin beauty and arthritis prevention. Enzymatic synthesis is a significant strategy to obtain oligosaccharides and polysaccharides with uniform chain length and well-defined structure. However, the limitations of glycosyltransferase, such as low expression, poor stability, and difficulty in reuse, greatly restrict its application in large-scale commercial production. In this study, we constructed the expression system for hyaluronic acid synthase PmHAS and chondroitin synthase KfoC to obtain the enzyme with high expression level and good water solubility. Subsequently, we screened and optimized several highly biocompatible metal-organic frameworks (MOFs) to immobilize two glycosyltransferases efficiently. The resulting enzyme@MOF composite can catalyze the synthesis of hyaluronic acid and chondroitin oligosaccharides/polysaccharides in quantitative yield. Meanwhile, the supramolecular interactions between enzyme and hydrophilic MOFs confer satisfactory stability, durability, and reusability on immobilized PmHAS and KfoC.