Bagdonaitė Ru Ta, Žvirblis Rokas, Dodonova-Vaitku Nienė Jelena, Polita Artu Ras
Department of Biospectroscopy and Bioelectrochemistry, Institute of Biochemistry, Life Sciences Center, Vilnius University, Saulėtekio av. 7, Vilnius LT-10257, Lithuania.
Department of Biothermodynamics and drug design, Institute of Biotechnology, Life Sciences Center, Vilnius University, Saulėtekio av. 7, Vilnius LT-10257, Lithuania.
JACS Au. 2025 Apr 14;5(4):2004-2014. doi: 10.1021/jacsau.5c00253. eCollection 2025 Apr 28.
Lysosomes are dynamic, membrane-bound organelles that play key roles in cellular waste disposal, macromolecule recycling, and signaling. Disruptions in lysosomal function and lipid composition are implicated in a wide range of diseases including lysosomal storage disorders, fatty liver disease, atherosclerosis, and cancer. Imaging of the lysosomal lipid composition has the potential to not only enhance the understanding of lysosome-related diseases and their progression but also help identify them. In this work, we present a novel viscosity-sensitive, green-emitting BODIPY probe that can distinguish between ordered and disordered lipid phases and selectively internalize into the lysosomal membranes of live cells. Through the use of fluorescence lifetime imaging microscopy, we demonstrate that lysosomal membranes in multiple cancer cells exhibit significantly higher microviscosities compared to noncancer cells. The differences in lysosomal microviscosities provide an effective approach for identifying cancer cells and indicate that malignant cells may possess more oxidized and saturated lysosomal lipid membranes. Furthermore, we demonstrate the utility of viscosity-sensitive probes in quantifying the compositional changes in lysosomal membranes by investigating the effects of lysosome-permeabilizing cationic amphiphilic drugs (CADs), sertraline, and astemizole. Our results reveal that despite their functional similarities, these CADs exert opposite effects on lysosomal microviscosities in both cancerous and noncancerous cells, suggesting that different mechanisms may contribute to the CAD-induced lysosomal damage and leakage.
溶酶体是动态的、膜结合的细胞器，在细胞废物处理、大分子循环和信号传导中发挥关键作用。溶酶体功能和脂质组成的破坏与多种疾病有关，包括溶酶体贮积症、脂肪肝疾病、动脉粥样硬化和癌症。对溶酶体脂质组成进行成像不仅有可能增进对溶酶体相关疾病及其进展的理解，还有助于对这些疾病进行识别。在这项工作中，我们展示了一种新型的对粘度敏感、发出绿色荧光的硼二吡咯（BODIPY）探针，它能够区分有序和无序的脂质相，并选择性地内化到活细胞的溶酶体膜中。通过使用荧光寿命成像显微镜，我们证明，与非癌细胞相比，多种癌细胞中的溶酶体膜表现出显著更高的微粘度。溶酶体微粘度的差异为识别癌细胞提供了一种有效的方法，并表明恶性细胞可能拥有更多氧化和饱和的溶酶体脂质膜。此外，我们通过研究溶酶体通透阳离子两亲性药物（CADs）、舍曲林和阿司咪唑的作用，证明了粘度敏感探针在量化溶酶体膜组成变化方面的实用性。我们的结果表明，尽管这些CADs功能相似，但它们对癌细胞和非癌细胞的溶酶体微粘度产生相反的影响，这表明不同的机制可能导致CADs诱导的溶酶体损伤和渗漏。
