LHVS

LHVS is a potent, non-selective, irreversible, and cell-permeable cysteine protease and cathepsin inhibitor. LHVS also inhibits T. gondii invasion (IC₅₀=10μM)^[1-2]. Through its vinyl sulfone moiety, LHVS covalently modifies the thiol group at the active site of cathepsin S, thereby achieving high selectivity in inhibiting cathepsin S activity. LHVS can be used in research related to neuropathic pain and the autophagy/lysosomal degradation pathway^[3-4].

In vitro, treatment of the B-lymphoblastoid cell line HOM2 with LHVS (1–5nM) for 1 hour specifically inhibited cathepsin S activity, prevented complete proteolysis of the invariant chain, and significantly reduced the formation of SDS-stable αβ dimers^[5]. Treatment of MCF7 tumor cells and U-937 macrophage-like cells with LHVS (10nM) for 72 hours did not show a significant effect on cell proliferation^[6].

In vivo, a single intracerebroventricular (i.c.v.) injection of LHVS (10–50nM; 6μL) was administered to male ICR mice 10 minutes before the induction of traumatic brain injury (TBI). LHVS significantly reduced the levels of the pro-inflammatory cytokines IL-1β and TNF-α in the injured cortex, alleviated brain edema at 24 hours post-TBI, suppressed neuronal degeneration in the cortex, and improved neurobehavioral scores in mice at 24 hours after injury^[7]. Daily intraperitoneal injection of LHVS (25mg/kg), starting from day 0 to day 15 of MOG₃₅₋₅₅ immunization to induce experimental autoimmune encephalomyelitis (EAE), was administered to both wild-type (WT) and cathepsin S-deficient (Cat S⁻/⁻) C57BL/6 mice. LHVS completely prevented the clinical onset of MOG₃₅₋₅₅-induced EAE in both WT and Cat S⁻/⁻ mice and significantly reduced the number of infiltrating macrophages, microglia, CD4⁺ T cells, CD8⁺ T cells, and B cells in the spinal cord^[8].

References:
[1] Wilson SR, Peters C, Saftig P, et al. Cathepsin K activity-dependent regulation of osteoclast actin ring formation and bone resorption. J Biol Chem. 2009 Jan 23;284(4):2584-92.
[2] Teo CF, Zhou XW, Bogyo M, et al. Cysteine protease inhibitors block Toxoplasma gondii microneme secretion and cell invasion. Antimicrob Agents Chemother. 2007 Feb;51(2):679-88.
[3] Barclay J, Clark AK, Ganju P, et al. Role of the cysteine protease cathepsin S in neuropathic hyperalgesia. Pain. 2007 Aug;130(3):225-234.
[4] Fujii H, Ivison SM, Shimizu H, et al. Inhibition of cathepsin S reduces allogeneic T cell priming but not graft-versus-host disease against minor histocompatibility antigens. Biol Blood Marrow Transplant. 2012 Apr;18(4):546-56.
[5] Riese RJ, Wolf PR, Brömme D, et al. Essential role for cathepsin S in MHC class II-associated invariant chain processing and peptide loading. Immunity. 1996 Apr;4(4):357-66.
[6] Mitrović A, Senjor E, Jukić M, et al. New inhibitors of cathepsin V impair tumor cell proliferation and elastin degradation and increase immune cell cytotoxicity. Comput Struct Biotechnol J. 2022 Aug 28;20:4667-4687.
[7] Xu J, Wang H, Ding K, et al. Inhibition of cathepsin S produces neuroprotective effects after traumatic brain injury in mice. Mediators Inflamm. 2013;2013:187873.
[8] Allan ER, Yates RM. Redundancy between Cysteine Cathepsins in Murine Experimental Autoimmune Encephalomyelitis. PLoS One. 2015 Jun 15;10(6):e0128945.

LHVS是一种有效的、非选择性的、不可逆的、可透过细胞的半胱氨酸蛋白酶和组织蛋白酶抑制剂，LHVS还可以抑制T. gondii（IC₅₀=10μM）侵袭^[1-2]。LHVS通过其乙烯基砜部分共价修饰组织蛋白酶S活性位点的巯基，实现对组织蛋白酶S的高选择性抑制。LHVS可用于神经病理性疼痛和自噬/溶酶体降解途径的相关研究^[3-4]。

在体外，LHVS（1-5nM）处理B淋巴母细胞系HOM2细胞1小时，可特异性抑制组织蛋白酶S的活性，阻止不变链的完全蛋白水解，并显著减少SDS稳定复合物的形成^[5]。LHVS（10nM）处理MCF7肿瘤细胞及U-937巨噬细胞72小时。LHVS未显示出对细胞增殖的显著影响^[6]。

在体内，LHVS（10-50nM；6μL）在创伤性脑损伤（TBI）诱导前10分钟，通过脑室内注射（i.c.v.）单次给药处理ICR雄性小鼠。LHVS显著降低了脑损伤皮层中促炎因子IL-1β和TNF-α的水平，减轻了创伤后24小时的脑水肿，抑制了皮层中神经元的退化，并改善了小鼠在创伤后24小时的神经行为功能评分^[7]。LHVS（25mg/kg）每日腹腔注射，从用MOG_35-55免疫诱导实验性自身免疫性脑脊髓炎（EAE）的第0天开始给药15天，持续处理野生型（WT）和Cathepsin S缺陷型（Cat S^-/-）C57BL/6小鼠。LHVS完全阻止了MOG_35-55诱导的EAE在WT和Cat S^-/-小鼠中的临床发病，并显著减少了脊髓中浸润的巨噬细胞、小胶质细胞、CD4+ T细胞、CD8+ T细胞和B细胞的数量^[8]。