Condoliase(Seikagaku Corp.)

引言 胰岛素抵抗与外周组织的细胞外基质（ECM）重塑密切相关，过度的ECM沉积（即纤维化现象）会通过增加组织刚度，改变胰岛素在细胞膜受体上的结合效率，阻碍胰岛素信号的正常传播，进而加剧了胰岛素抵抗的程度【1】。传统上认为纤维化主要在脂肪组织、骨骼肌及肝脏等外周组织中发生，对代谢稳态产生至关重要的影响【2】。然而，近年来的研究揭示，纤维化不仅限于外周组织，在急性脑损伤和多种神经系统疾病中，也观察到了大脑内的ECM重塑现象【3】。 最近研究表明，大脑特定区域中，尤其是下丘脑弓状核（ARC）中的ECM重塑可能与代谢调控密切相关。ARC是一个已知的控制食欲和能量代谢的关键区域，其中表达食欲相关肽（AgRP）的神经元在能量平衡中发挥了核心作用。在神经元成熟的过程中，AgRP神经元周围形成了一种特殊的ECM亚型——神经元周围网（PNNs）【4】。PNNs通过支持结构形成和调节微环境，直接影响AgRP神经元的功能，当PNNs结构受损时，AgRP神经元周围的纤维密度增加，同时伴随着细胞数量的变化，这体现了PNNs的完整性对于维持ARC神经元的代谢功能至关重要。 此外，ARC及其附近区域的ECM重塑具有动态性，能够根据外界营养状况发生快速变化。这种可塑性反映了ECM在神经内分泌系统中的潜在作用，可能通过调节神经元与其微环境间的互作，影响代谢信号的传递和调控【5】。鉴于纤维化在外周组织中与细胞功能障碍之间的密切关联，ARC中的ECM重塑可能为理解代谢性疾病的发病机制提供全新视角。 近日，墨尔本大学Garron T. Dodd实验室领衔在Nature杂志发表了题为Pathog enic hypothalamic extracellular matrix promotes metabolic disease的研究文章，发现高脂高糖饮食会导致下丘脑ARC中的PNN重塑，损害胰岛素信号，导致AgRP神经元功能异常及代谢紊乱。通过酶解PNN或使用氟氨糖抑制神经纤维化，可恢复胰岛素敏感性。此外，下丘脑炎症是驱动PNN重塑的关键因素，抑制炎症可有效缓解纤维化和代谢失调。 通过WFA染色发现，在高脂高糖饮食下，小鼠下丘脑ARC区域的神经纤维化显著加剧，这一变化特异性发生在ARC区域，与代谢疾病的发生紧密相关。而在肥胖诱导的神经纤维化过程中，ARC中的PNN与ECM的组成发生了显著变化。透明质酸与WFA信号在ARC中几乎完全共定位，且在肥胖小鼠中其含量增加。此外，软骨素硫酸蛋白聚糖（CSPG）成分也在肥胖过程中显著增加，凝聚素增加与PNN的变化高度相关。因此，肥胖会促使ARC中多种主要ECM成分的增加，而凝聚素在神经纤维化中起着关键作用。 ARC包含两类与代谢密切相关的神经元群体：AgRP神经元和促黑皮质素原（POMC）神经元。正常条件下，大约45%的AgRP神经元和24%的POMC神经元被PNN包裹。而在代谢疾病发生过程中，AgRP神经元周围的PNN显著增加，并伴随着WFA和凝聚素的增强，可见代谢疾病的发展与ARC中AgRP神经元周围的神经纤维化密切相关。此外，PNNs被认为具有较慢的更新速率，然而作者发现在促肥胖饮食作用下，ARC中的PNN重塑和更新速度相对较快。 为确定体内状态下PNN的更新速率，作者开发了基于“脉冲-追踪”技术的“PNN追踪器”，以标记感兴趣脑区的PNN变化。作者证明了“PNN追踪器”可以可靠地标记ARC中的PNN，并验证了WFA-生物素能够准确标记注射时存在的PNN。“PNN追踪器”数据表明ARC中的PNN更新周期约为五周，远快于其他脑区。此外，ARC中PNN的快速降解表明其在代谢调控中可能具有独特的生理功能，同时也显示了不同脑区在ECM更新方面存在显著差异。这为进一步研究脑区特异的PNN功能提供了重要线索。 接下来作者验证了ARC中的神经纤维化是否是由于PNN降解减少所导致的，发现与瘦小鼠相比，肥胖小鼠的PNN降解速度显著减慢，并且与PNN相关的关键蛋白酶在肥胖小鼠中的表达减少。因此，PNN降解的减少导致了ARC中的神经纤维化，并推动了代谢疾病的进展。抑制ARC神经纤维化不仅降低了体重和脂肪含量，还增强了全身能量消耗和组织的热生成，改善了胰岛素敏感性和葡萄糖稳态，表明ARC神经纤维化在肥胖及代谢疾病的发生中起着关键作用。 另一方面，作者发现肥胖引发的神经纤维化通过阻碍胰岛素进入下丘脑的ARC区域，导致胰岛素信号传导受损。通过注射软骨素酶ABC（chABC）选择性解构PNN，肥胖小鼠的ARC区域胰岛素信号得以恢复，而这并不依赖于体重的变化。此外，PNN中的葡萄糖胺聚糖的负电荷是胰岛素与PNN相互作用的关键，这为ARC神经纤维化在肥胖相关胰岛素抵抗中的作用提供了机制性解释。同时，这种现象特异于胰岛素，未对瘦素产生类似影响，表明ARC神经纤维化主要调节胰岛素的进入和信号传导。 此外，ARC中的PNN通过调节AgRP神经元的电生理特性与能够胰岛素直接互作。肥胖状态下，神经纤维化导致AgRP神经元对胰岛素的响应减弱，从而加剧胰岛素抵抗。AgRP神经元中胰岛素受体的功能性信号对于代谢调节至关重要。通过CRISPR技术生成的小鼠模型显示，去除ARC神经纤维化能够恢复胰岛素信号，从而改善代谢健康和血糖控制。 不仅如此，下丘脑炎性反应会影响细胞外基质重塑和整体的代谢功能。通过抗炎和促炎实验，作者确认了下丘脑炎症与神经纤维化之间存在明显的关联性，且下丘脑炎症促进病理性PNN重塑，这是全身代谢功能障碍的因果驱动因素。最后，作者探索了靶向神经纤维化的药理潜力，检测了CS-GAG链组装和延长酶的抑制剂——氟氨糖对神经纤维化和代谢的影响，发现氟氨糖作为一种小分子抑制剂，能够有效靶向神经纤维化，进而改善代谢健康。 综上所述，本研究发现高脂高糖饮食会导致ARC中神经元周围的PNN重塑，进而引起胰岛素信号传导受损、AgRP神经元功能异常以及全身代谢失调。通过酶解PNN或者使用小分子抑制剂氟氨糖来靶向和逆转ARC中的神经纤维化，可以恢复胰岛素敏感性并缓解代谢紊乱。此外，本研究还揭示了下丘脑炎症作为驱动ARC中PNN重塑的诱因，通过抑制炎症可以显著抑制神经纤维化和代谢失调。未来研究中，研究人员可以进一步探索如何更精准地调控PNN重塑，并以此开发针对神经纤维化的药物，这将为肥胖和糖尿病等代谢性疾病的治疗带来新的希望。 参考文献 1. Guglielmi, V. et al. Omental adipose tissue fibrosis and insulin resistance in severe obesity. Nutr. Diabetes 5, e175 (2015). 2. Berria, R. et al. Increased collagen content in insulin-resistant skeletal muscle. Am. J. Physiol. Endocrinol. Metab. 290, E560–E565 (2006). 3. Shijo, T. et al. Aberrant astrocytic expression of chondroitin sulfate proteoglycan receptors in a rat model of amyotrophic lateral sclerosis. J. Neurosci. Res. 96, 222–233 (2018). 4. Mirzadeh, Z. et al. Perineuronal net formation during the critical period for neuronal maturation in the hypothalamic arcuate nucleus. Nat. Metab. 1, 212–221 (2019). 5. Kohnke, S. et al. Nutritional regulation of oligodendrocyte differentiation regulates perineuronal net remodeling in the median eminence. Cell Rep. 36, 109362 (2021). https://doi.org/10.1038/s41586-024-07922-y 责编|探索君 排版|探索君 文章来源|“BioArt” End 往期精选 围观 一文读透细胞死亡(Cell Death) | 24年Cell重磅综述（长文收藏版） 热文 Cell | 是什么决定了细胞的大小？ 热文 Nature | 2024年值得关注的七项技术 热文 Nature | 自身免疫性疾病能被治愈吗？科学家们终于看到了希望 热文 CRISPR技术进化史 | 24年Cell综述

PARSIPPANY, N.J.--( BUSINESS WIRE )--Ferring Pharmaceuticals and its clinical development partner, Seikagaku Corporation (Seikagaku), today announced the presentation of data from two Phase 3 trials evaluating the efficacy and safety of SI-6603 (generic name: condoliase), an investigational product being studied for the treatment of radicular leg pain associated with lumbar disc herniation (LDH). The podium presentation at the North American Spine Society’s (NASS) Annual Meeting included results from one study conducted in the U.S. and one in Japan. In addition, The Spine Journal has published the results of the pivotal U.S. Phase 3 study. NASS Presentation In the double-blind, sham or placebo controlled Phase 3 studies, patients with LDH were randomized to receive either a single intradiscal injection of SI-6603 1.25 Units or control (sham injection for U.S. study; placebo injection for Japanese study) followed by 52 weeks of observation. The modified intention-to-treat population in the U.S. study included 341 participants (SI-6603 n=169; sham n=172), and the study population in Japan included 163 participants (SI-6603 n=82; placebo n=81). The studies met their primary endpoint, showing significantly greater change from baseline (CFB) in worst leg pain at Week 13 compared to sham (U.S.) / placebo (Japan) (least squares mean [LSM] difference: -7.5 [p=0.0263] for the U.S. study and -15.2 [p=0.001] for the Japan study). “ Treatment for radicular leg pain associated with lumbar disc herniation is currently limited to conservative pain management and physical therapy or surgery. The data from these two Phase 3 studies further support the potential of SI-6603 as a therapeutic option for the millions of Americans suffering from the debilitating impact of this condition, ” said Kee Kim, MD, University of California, Davis. The most common treatment-emergent adverse events (TEAEs) in the U.S. trial were spinal magnetic resonance imaging abnormalities (SI-6603 28.1%; sham 9.2%) and back pain (SI-6603 19.2%; sham 12.6%). In the Japan trial, the most common TEAEs were back pain (SI-6603 36.6%; placebo 33.3%) and leg pain (SI-6603 25.6%; placebo 35.8%). There were no treatment-related serious adverse events (SAEs) with SI-6603 in the U.S. study, and in the Japan study, one SAE (back pain) was considered potentially related to SI-6603. About the Phase 3 Trial in the U.S. In this randomized double-blind, sham-controlled, parallel Phase 3 study — known as the Discovery 6603 clinical trial (NCT03607838) — participants were randomized 1:1 to receive either SI-6603 (1.25 U) or sham injection followed by 52 weeks of observation. The primary endpoint was defined as the CFB to Week 13 in worst leg pain during the past 24 hours averaged over the previous seven days, as assessed by Visual Analogue Scale, a pain rating score from 0 – 100 with a higher score indicating greater pain intensity. Key secondary endpoints included the CFB in average worst leg pain at 52 weeks, percentage of participants with negative straight leg raise test, and 50% responder rates for worst leg pain and Oswestry Disability Index (ODI). Since the key secondary endpoint of change in average worst leg pain at Week 52 was not significant, the serial gatekeeping testing algorithm dictated that there were no significant group differences for Week 13 herniation volume or ODI score regardless of their p-values. Endpoints were assessed using a mixed model for repeated measures (MMRM) analysis of the modified intention-to-treat population (mITT). The trial included U.S. participants ages 30 to 70 years old who had contained posterolateral LDH with the chief complaint being unilateral radiculopathy/radicular leg pain and inadequate improvement in pain despite more than six weeks of conservative treatment. Among 352 randomized participants, 341 constituted the mITT population (SI-6603 n=169; sham injections n=172). About the Phase 3 Trial in Japan In this randomized, double-blind, placebo-controlled study, participants were randomized 1:1 to receive either a single injection of SI-6603 (1.25U) or placebo injection, followed by 52 weeks of observation. The primary endpoint was the CFB to Week 13 in average worst leg pain during the past 24 hours over the previous seven days, as assessed by Visual Analogue Scale, a pain rating score from 0 – 100 with a higher score indicating greater pain intensity. Secondary endpoints included CFB up to Week 52 in average worst leg pain, herniation volume and ODI score. Endpoints were assessed using an analysis of covariance model. About Lumbar Disc Herniation About 9 million adults in the U.S. suffer from lumbar disc herniation each year. A disc herniation is a displacement of the gel-like inner core of the intervertebral disc, called the nucleus pulposus, through its external membrane (annulus fibrosus) due to wear and tear, aging or sudden injury. As a result of this displacement, the disc presses on the spinal nerve, often producing pain. 1,2 About SI-6603 SI-6603, which contains condoliase as its active pharmaceutical ingredient, is an investigational product being studied for the treatment of radicular leg pain associated with lumbar disc herniation via a single, direct intradiscal injection. SI-6603 (condoliase) is designed to reduce nerve root compression and thereby the radicular leg pain. SI-6603 was developed by Seikagaku. Marketing approval for SI-6603 in Japan was obtained from the Japanese Ministry of Health, Labour and Welfare in March 2018 and SI-6603 has been marketed in Japan only as HERNICORE ® 1.25 units for intradiscal injection through Seikagaku's Japanese sales partner Kaken Pharmaceutical Co., Ltd. (Tokyo, Japan) since August 1, 2018. 3 Alliance with Seikagaku Seikagaku and Ferring entered into a license agreement for SI-6603 in August 2016. Ferring plans to commercialize the product in the United States upon FDA approval and has received further rights to develop, register and commercialize SI-6603 worldwide, excluding Japan. About Ferring Pharmaceuticals Ferring Pharmaceuticals is a privately-owned, research-driven, specialty biopharmaceutical group committed to building families and helping people live better lives. In the United States, Ferring is a leader in reproductive medicine and maternal health, and in areas of gastroenterology and orthopaedics. We are at the forefront of innovation in microbiome-based therapeutics and uro-oncology intravesical gene therapy. Our company was founded in 1950 and is headquartered in Saint-Prex, Switzerland. Ferring employs more than 7,000 people worldwide and markets its medicines in over 100 countries. Ferring USA is based in Parsippany, New Jersey, and employs more than 900 employees. For more information, please visit www.ferringusa.com , call 1-888-FERRING (1-888-337-7464), or connect with us on LinkedIn and X (Twitter) . References: Vialle LR, Vialle EN, Suárez Henao JE, Giraldo G. Lumbar Disc Herniation. Rev Bras Ortop . 2015 Nov 16;45(1):17-22. doi: 10.1016/S2255-4971(15)30211-1. PMID: 27019834; PMCID: PMC4799068. Herniated Disk in the Lower Back. OrthoInfo. American Academy of Orthopaedic Surgeons. Available at: https://orthoinfo.aaos.org/en/diseases–conditions/herniated-disk-in-the-lower-back/ . Accessed May 23, 2023. Press Release. Seikagaku and Kaken Announce the Launch of HERNICORE ® 1.25 Units for Intradiscal Injection in Japan. July 31,2018. Available at: https://www.seikagaku.co.jp/en/news/news-6617037418084939174/main/0/link/20180731-e.pdf . Accessed May 24, 2023.