Gene therapy is under advanced clinical development for several lysosomal storage disorders. Pompe disease, a debilitating neuromuscular illness that affects infants, children, and adults with different degrees of severity, is caused by a deficiency of lysosomal glycogen-degrading enzyme acid alpha-glucosidase (GAA). Here, we demonstrated that adeno-associated virus (AAV9)-mediated systemic gene transfer fully reversed glycogen storage in all key therapeutic targets - skeletal and cardiac muscles, the diaphragm, and the central nervous system (CNS) - in both young and severely affected old Gaa knockout mice. Furthermore, the therapy reversed secondary cellular abnormalities in skeletal muscle, such as autophagy and mTORC1/AMPK signaling. We used a newly developed AAV9 vector encoding a chimeric human GAA protein with enhanced uptake and secretion to facilitate efficient spread of the expressed protein among multiple target tissues. These results lay the groundwork for future clinical development strategy in Pompe disease.
Naresh K Meena, Davide Randazzo, Nina Raben, Rosa Puertollano
Lysine-specific demethylase 1 (LSD1) is a histone demethylase that promotes stemness and cancer cell survival, including in prostate cancer. Most prostate malignancies are adenocarcinomas with luminal differentiation. However, some tumors undergo cellular reprogramming to a more lethal subset termed neuroendocrine prostate cancer (NEPC) with neuronal differentiation. The frequency of NEPC is increasing since widespread use of potent androgen receptor signaling inhibitors. Currently, there are no effective treatments for NEPC. We previously determined that LSD1 promotes survival of prostate adenocarcinoma tumors. However, the role of LSD1 in NEPC is unknown. Here, we determined that LSD1 is highly upregulated in NEPC vs. adenocarcinoma patient tumors. LSD1 suppression with RNAi or allosteric LSD1 inhibitors—but not catalytic inhibitors—reduced NEPC cell survival. RNA-seq analysis revealed that LSD1 represses pathways linked to luminal differentiation, and TP53 was the top reactivated pathway. We confirmed that LSD1 suppressed the TP53 pathway by reducing TP53 occupancy at target genes while LSD1’s catalytic function was dispensable for this effect. Mechanistically, LSD1 inhibition disrupted LSD1-HDAC interactions, increasing histone acetylation at TP53 targets. Finally, LSD1 inhibition suppressed NEPC tumor growth in vivo. These findings suggest that blocking LSD1’s non-catalytic function may be a promising new treatment strategy for NEPC.
Anbarasu Kumaraswamy, Zhi Duan, Diana Flores, Chao Zhang, Archana Sehrawat, Ya-Mei Hu, Olivia A. Swaim, Eva Rodansky, William K. Storck, Joshua A. Kuleape, Karan Bedi, Rahul Mannan, Xiao-Ming Wang, Aaron M. Udager, Visweswaran Ravikumar, Armand Bankhead III, Ilsa Coleman, John K. Lee, Colm Morrissey, Peter S. Nelson, Arul Chinnaiyan, Arvind Rao, Zheng Xia, Joel A. Yates, Joshi J. Alumkal
Reactive oxygen species (ROS) are natural products of mitochondrial oxidative metabolism and oxidative protein folding. ROS levels must be well controlled as elevated ROS has been shown to have deleterious effects on osteoblasts. Moreover, excessive ROS is thought to underly many of the skeletal phenotypes associated with aging and sex steroid deficiency in mice and humans. The mechanisms by which osteoblasts regulate ROS and how ROS inhibits osteoblasts are not well understood. Here, we demonstrate that de novo glutathione (GSH) biosynthesis is essential to neutralize ROS and establish a pro-osteogenic REDOX environment. Using a multifaceted approach, we demonstrate that reducing GSH biosynthesis leads to acute degradation of RUNX2, impaired osteoblast differentiation and reduced bone formation. Conversely, reducing ROS using Catalase enhances RUNX2 stability and promotes osteoblast differentiation and bone formation when GSH biosynthesis is limited. Highlighting the therapeutic implications of these findings, in utero antioxidant therapy stabilizes RUNX2 and improves bone development in the Runx2+/- haploinsufficient mouse model of human Cleidocranial Dysplasia. Thus, our data establish RUNX2 as a molecular sensor of the osteoblast REDOX environment and mechanistically clarifies how ROS negatively impacts osteoblast differentiation and bone formation.
Guoli Hu, Yilin Yu, Deepika Sharma, Shondra M. Pruett-Miller, Yinshi Ren, Guo-Fang Zhang, Courtney M. Karner
Morrbid is a new identified leukocyte-specific long noncoding RNA (lncRNA). However, the expression and biological functions of Morrbid in cardiomyocytes and in heart disease are currently unclear. The study is to determine the roles of cardiac Morrbid in acute myocardial infarction (AMI) and to identify the potential cellular and molecular mechanisms involved. We found that both human and mouse cardiomyocytes could express a significant amount of Morrbid and its expression was increased in cardiomyocytes with hypoxia or oxidative stress, and in mouse hearts with AMI. Overexpression of Morrbid reduced the myocardial infarct size and cardiac dysfunction, whereas the infarct size and cardiac dysfunction were deteriorated in cardiomyocyte-specific Morrbid knockout (Morrbidfl/fl/Myh6-Cre) mice. We identified that Morrbid had a protective effect against hypoxia or H2O2-induce apoptosis, which was also confirmed in vivo in mouse hearts after AMI. We further discovered that serpine1 was a direct target gene of Morrbid, which was involved in Morrbid-mediated protective effect on cardiomyocytes. In summary, we have found for the first time that the cardiac Morrbid is a stress-enhanced lncRNA, which protects hearts from AMI via anti-apoptosis through its target gene serpine1. Morrbid may be a novel promising therapeutic target for ischemic heart diseases such as AMI.
Yang Yu, Haiqiong Yang, Qiuting Li, Nianhui Ding, Jiali Gao, Gan Qiao, Jianguo Feng, Xin Zhang, Jianming Wu, Yajun Yu, Xiangyu Zhou, Xiaobin Wang, Chunxiang Zhang
Dyslipidemia in obesity results from excessive production and impaired clearance of triglyceride (TG)-rich lipoproteins, which is particularly pronounced in the postprandial state. Here, we investigated the impact of Roux-en-Y gastric bypass (RYGB) surgery on the postprandial VLDL1 and VLDL2 apoB and TG kinetics and their relationship with insulin responsiveness indices. 24 obese non-diabetic RYGB surgery patients underwent a lipoprotein kinetics study during a mixed meal test and a hyperinsulinemic-euglycemic clamp study before the surgery, and one year later. A physiologically based computational model was developed to investigate the impact of RYGB surgery and plasma insulin on postprandial VLDL kinetics. After the surgery, VLDL1 apoB and TG production rates were significantly decreased, whereas VLDL2 apoB and TG production rates remained unchanged. TG catabolic rate was increased in both VLDL1 and VLDL2 fractions, but only the VLDL2 apoB catabolic rate tended to increase. Furthermore, post-surgery VLDL1 apoB and TG production rates, but not VLDL2, were positively correlated with insulin resistance. Insulin-mediated stimulation of peripheral lipoprotein lipolysis was also improved after the surgery. In summary, RYGB resulted in a reduced hepatic VLDL1 production that correlated with reduced insulin resistance, an elevated VLDL2 clearance, and improved insulin sensitivity in lipoprotein lipolysis pathways.
Vehpi Yildirim, Kasper W. ter Horst, Pim W. Gilijamse, Dewi van Harskamp, Henk Schierbeek, Hans Jansen, Alinda W.M. Schimmel, Max Nieuwdorp, Albert K. Groen, Mireille J. Serlie, Natal A.W. van Riel, Geesje M. Dallinga-Thie
U1RNP complex, Ro/SSA and La/SSB are major RNA-containing autoantigens. Immune complexes (ICs) composed of RNA-containing autoantigens and autoantibodies are suspected to be involved in the pathogenesis of some systemic autoimmune diseases. Therefore, RNase treatment, which degrades RNA in ICs, has been tested in clinical trials as a potential therapeutic agent. However, no studies have specifically evaluated the effect of RNase treatment on the Fcγ receptor-stimulatory activity of RNA-containing ICs. In this study, using a reporter system that specifically detects Fcγ receptor-stimulatory capacity, we investigated the effect of RNase treatment on the Fcγ receptor-stimulatory activity of RNA-containing ICs composed of autoantigens and autoantibodies from patients with systemic autoimmune diseases such as systemic lupus erythematosus. We found that RNase enhanced the Fcγ receptor-stimulatory activity of Ro/SSA- and La/SSB-containing ICs, but attenuated that of the U1RNP complex-containing ICs. RNase decreased autoantibody binding to the U1RNP complex, but increased autoantibody binding to Ro/SSA and La/SSB. Our results suggest that RNase enhances Fcγ receptor activation by promoting the formation of ICs containing Ro/SSA or La/SSB. Our study provides new insights into the pathophysiology of autoimmune diseases involving anti-Ro/SSA and anti-La/SSB autoantibodies, and into the therapeutic application of RNase treatment for systemic autoimmune diseases.
Ryota Naito, Koichiro Ohmura, Shuhei Higuchi, Wataru Nakai, Masako Kohyama, Tsuneyo Mimori, Akio Morinobu, Hisashi Arase
Proline and its synthesis enzyme pyrroline-5-carboxylate reductase 1 (PYCR1) are implicated in epithelial-mesenchymal transition (EMT), yet how proline and PYCR1 function in allergic asthmatic airway remodeling via EMT has not yet been addressed. In the present study, increased levels of plasma proline and PYCR1 were observed in asthmatic patients. Similarly, proline and PYCR1 in lung tissues were higher in a murine allergic asthma model induced by house dust mites (HDMs). Pycr1 knockout (KO) decreased proline in lung tissues, with reduced airway remodeling and EMT. Mechanistically, loss of Pycr1 restrained HDM-induced EMT by modulating mitochondrial fission, metabolic reprogramming, and the AKT/mTOR1 and WNT3a/β–catenin signaling pathways in airway epithelial cells. Therapeutic inhibition of PYCR1 in wild-type mice disrupted HDM-induced airway inflammation and remodeling. Deprivation of exogeneous proline partially relieved HDM-induced airway remodeling to some extent. Collectively, this study illuminates that proline and PYCR1 involved with airway remodeling in allergic asthma could be viable targets for asthma treatment.
Tingting Xu, Zhenzhen Wu, Qi Yuan, Xijie Zhang, Yanan Liu, Chaojie Wu, Meijuan Song, Jingjing Wu, Jingxian Jiang, Zhengxia Wang, Zhongqi Chen, Mingshun Zhang, Mao Huang, Ningfei Ji
Transgender women (TGW) are disproportionally affected by HIV infection, with a global estimated prevalence of 19.9%, often attributed to behavioral risk factors, with less known about biological factors. We evaluated potential biological risk factors for HIV acquisition in TGW at the sites of viral entry by assessing immune parameters of neovaginal surface and gut mucosa. The neovagina in TGW, compared to the vagina in CW, shows distinct cell composition and may pose a more inflammatory environment, evidenced by increased CD4+ T cell activation and higher levels of soluble markers of inflammation (CRP, sCD30). Increased inflammation may be driven by microbiome composition, showing a greater abundance of Prevotella and a higher Shannon diversity. In addition, we have observed higher frequency of CD4+CCR5+ target cells and decreased DNA methylation of the CCR5 gene in the gut mucosa of TGW compared to CW and MSM which was inversely correlated with testosterone levels. The rectal microbiome composition in TGW appears to favor a proinflammatory milieu as well as mucosal barrier disruption. Thus, it is possible that increased inflammation and higher frequencies of CCR5-expressing target cells at sites of mucosal viral entry may contribute to increased risk of HIV acquisition in TGW, with further validation in larger studies warranted.
Alexandra Schuetz, Michael Corley, Carlo Sacdalan, Yuwadee Phuang-Ngern, Thitiyanun Nakpor, Tanyaporn Wansom, Philip K. Ehrenberg, Somchai Sriplienchan, Rasmi Thomas, Nisakorn Ratnaratorn, Suchada Sukhumvittaya, Nipattra Tragonlugsana, Bonnie M. Slike, Siriwat Akapirat, Suteeraporn Pinyakorn, Rungsun Rerknimitr, Alina P.S. Pang, Eugène Kroon, Nipat Teeratakulpisan, Shelly J. Krebs, Nittaya Phanuphak, Lishomwa C. Ndhlovu, Sandhya Vasan
Reducing inflammatory damage and improving alveolar epithelium regeneration are two key approaches to promoting lung repair in acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Stimulation of cholinergic-α7nAChR (α7 nicotinic acetylcholine receptor, coded by Chrna7) signaling could dampen lung inflammatory injury. However, whether activation of α7nAChR in alveolar type II (AT2) cells promotes alveolar epithelial injury repair and underlying mechanisms are elusive. Here, we found that α7nAChR was expressed on AT2 cells and was upregulated in response to LPS-induced ALI. Meanwhile, deletion of Chrna7 in AT2 cells impeded lung repair process and worsened lung inflammation in ALI. Using in vivo AT2 lineage-labeled mice and ex vivo AT2-derived alveolar organoids, we demonstrated that activation of α7nAChR expressed on AT2 cells improved alveolar regeneration by promoting AT2 cells to proliferate and subsequently differentiate toward alveolar type I (AT1) cells. Then we screened out the WNT7B signaling pathway by the RNA sequencing analysis of in vivo AT2 lineage-labeled cells, and further confirmed its indispensability for α7nAChR activation-mediated alveolar epithelial proliferation and differentiation. Thus, we have identified an unrecognized pathway that cholinergic-α7nAChR signaling determines alveolar regeneration and repair, which might provide us a novel therapeutic target for combating ALI.
Xiaoyan Chen, Cuiping Zhang, Tianchang Wei, Jie Chen, Ting Pan, Miao Li, Lu Wang, Juan Song, Cuicui Chen, Yan Zhang, Yuanlin Song, Xiao Su
Almost half of patients recovering from open chest surgery experience atrial fibrillation (AF) that results principally from inflammation in the pericardial space surrounding the heart. Given that post-operative AF is associated with increased mortality, effective measures to prevent AF after open-chest surgery are highly desirable. In this study, we tested the concept that extracellular vesicles (EVs) isolated from human atrial explant-derived cells can prevent post-operative AF. Middle-aged female and male rats were randomized to undergo sham operation or induction of sterile pericarditis followed by trans-epicardial injection of human EVs or vehicle into the atrial tissue. Pericarditis increased the probability of inducing AF while EV treatment abrogated this effect in a sex independent manner. EV treatment reduced infiltration of inflammatory cells and production of pro-inflammatory cytokines. Atrial fibrosis and hypertrophy seen after pericarditis was markedly attenuated by EV pre-treatment; an effect attributable to suppression of fibroblast proliferation by EVs. Our study demonstrates that injection of extracellular vesicles at the time of open-chest surgery shows prominent anti-inflammatory effects and prevents AF due to sterile pericarditis. Translation of this finding to patients might provide an effective new strategy to prevent post-operative AF by reducing atrial inflammation and fibrosis.
Sandrine Parent, Ramana Vaka, Yousef Risha, Clarissa Ngo, Pushpinder Kanda, Stanley Nattel, Saad Khan, David Courtman, Duncan J. Stewart, Darryl R. Davis
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