Project description:Abundant high molecular weight hyaluronic acid (HMW-HA) contributes to cancer resistance and possibly longevity of the longest-lived rodent, the naked mole-rat1,2. To study whether the benefits of increased HMW-HA could be transferred to other animal species, we generated a transgenic mouse overexpressing naked mole-rat hyaluronic acid synthase 2 gene (nmrHAS2). nmrHAS2 mice showed increase in hyaluronan levels in several tissues, and lower incidence of spontaneous and induced cancer, extended lifespan and improved healthspan. The transcriptome signature of nmrHAS2 mice shifted towards that of longer-lived species. The most striking change observed in nmrHAS2 mice was attenuated inflammation across multiple tissues. HMW-HA reduced inflammation via several pathways including direct immunoregulatory effect on immune cells, protection from oxidative stress, and improved gut barrier function during aging. These findings demonstrate that the longevity mechanism that evolved in the naked mole-rat can be exploited to other species, and open new avenues for using HMW-HA to improve lifespan and healthspan.
Project description:Abundant high molecular weight hyaluronic acid (HMW-HA) contributes to cancer resistance and possibly longevity of the longest-lived rodent, the naked mole-rat1,2. To study whether the benefits of increased HMW-HA could be transferred to other animal species, we generated a transgenic mouse overexpressing naked mole-rat hyaluronic acid synthase 2 gene (nmrHAS2). nmrHAS2 mice showed increase in hyaluronan levels in several tissues, and lower incidence of spontaneous and induced cancer, extended lifespan and improved healthspan. The transcriptome signature of nmrHAS2 mice shifted towards that of longer-lived species. The most striking change observed in nmrHAS2 mice was attenuated inflammation across multiple tissues. HMW-HA reduced inflammation via several pathways including direct immunoregulatory effect on immune cells, protection from oxidative stress, and improved gut barrier function during aging. These findings demonstrate that the longevity mechanism that evolved in the naked mole-rat can be exploited to other species, and open new avenues for using HMW-HA to improve lifespan and healthspan
Project description:Abundant high molecular weight hyaluronic acid (HMW-HA) contributes to cancer resistance and possibly longevity of the longest-lived rodent, the naked mole-rat1,2. To study whether the benefits of increased HMW-HA could be transferred to other animal species, we generated a transgenic mouse overexpressing naked mole-rat hyaluronic acid synthase 2 gene (nmrHAS2). nmrHAS2 mice showed increase in hyaluronan levels in several tissues, and lower incidence of spontaneous and induced cancer, extended lifespan and improved healthspan. The transcriptome signature of nmrHAS2 mice shifted towards that of longer-lived species. The most striking change observed in nmrHAS2 mice was attenuated inflammation across multiple tissues. HMW-HA reduced inflammation via several pathways including direct immunoregulatory effect on immune cells, protection from oxidative stress, and improved gut barrier function during aging. These findings demonstrate that the longevity mechanism that evolved in the naked mole-rat can be exploited to other species, and open new avenues for using HMW-HA to improve lifespan and healthspan.
Project description:Background: HAS2 is a member of the gene family encoding hyaluronan synthase 2 (HAS2) which can generate high molecular weight hyaluronan (HMW-HA). Although we previously reported that HAS2 is a novel candidate gene for susceptibility to adult asthma., little is known about whether HAS2 dysfunction affect eosinophilic airway inflammation. Objective: We therefore hypothesized that attenuation of HAS2 will enhance eosinophilic airway inflammation. Methods: C57BL/6 wild type (WT) mice, Has2 heterozygous deficient (Has2+/−) mice were used in eosinophilic airway inflammation model which induced by ovalbumin (OVA). Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to detect Has2 and HA binding protein mRNA expression levels. Lung tissue and lavage fluid (BALF) were analyzed for inflammation and various cytokines and chemokines. Airway resistance was measured using forced oscillation technique. gene expression analyses were also performed to elucidate further pathogenesis. Results: The expression levels of Has2 mRNA was significantly decreased in OVA stimulated Has2+/− (Has2+/−-OVA) mice. Has2+/−-OVA mice also displayed significant reduce of CD44, and TGF-beta1 mRNA expression. BALF eosinophil number, levels of various Th2 cytokines and chemokines in BALF, and airway responsiveness were significantly increased in Has2+/−-OVA mice compared with similarly treated WT mice. ILK Signaling and PKA signaling were downregulated significantly more in Has2+/−-OVA mice compared with similarly treated WT mice. Conclusions: Has2 dysfunction induce more intense allergic eosinophilic airway inflammation and increase of airway hyper responsiveness with impairment of HAS2-CD44-TGF-beta signaling. Modulating HAS2 signaling might provide novel therapeutic targets for intractable bronchial asthma patients.
Project description:Background: HAS2 is a member of the gene family encoding hyaluronan synthase 2 (HAS2), which can generate high-molecular-weight hyaluronan (HMW-HA). Our previous study identified HAS2 as a candidate gene for susceptibility to adult asthma. However, little is known if HAS2 dysfunction affects airway remodeling and steroid insensivity. In this study, we clarified the dysfunction of Has2 triggering severe airway remodeling and steroid insensitivity in a murine model of asthma. Methods: Ovalbumin (OVA) was used to induce eosinophilic airway inflammation and airway remodeling in Has2 heterozygous deficient (Has2+/−) mice and their wild-type (WT) littermates. Lung tissue histology, bronchoalveolar lavage fluid cell counting, quantitative PCR, HA size analysis, multiplex cytokines and chemokines analysis, RNA sequencing, anti IL-17 neutralization experiment were performed. Results: After chronic OVA stimulation, Has2+/− (Has2+/--OVA) mice showed significant decrease of Has2 mRNA expression levels, HMW-HA, HA-binding protein, and TGF-β. Has2+/--OVA mice demonstrated increased eosinophilic airway inflammation, goblet cell hyperplasia, and IL-17 levels. RNA sequencing demonstrated downregulation of EIF2 signaling pathways, TGF-β signaling pathways, and heat shock proteins with Th17 bias in Has2+/--OVA mice. Combined treatment with anti IL-17 antibody and dexamethasone reduce steroid insensitivity in Has2+/--OVA mice Conclusions: Has2 attenuation worsen eosinophilic airway inflammation, airway remodeling, and steroid insensitivity. This severe intractable phenotype might be induced by impairment of TGF-β signaling and ER stress response related signaling. These data highlight that HAS2 and HMW-HA are important for controlling intractable eosinophilic airway inflammation and remodeling, and could potentially be exploited for therapeutic benefit to asthma patients.