ABSTRACT
Perfluorooctane sulfonate (PFOS), widely used in various industrial and commercial materials, can accumulate in the human body due to its high environmental stability, and thus potentially has cardiotoxicity. We assess cardiotoxicity through rat exposure to PFOS by intraperitoneal injection. Untargeted metabolomic analysis was used to explore the potential cardiotoxicity mechanism of PFOS. In vivo, PFOS exposure increases pro-inflammatory factors TNF-α and IL-1ß and decreases anti-inflammatory factors IL-10 and TGF-ß. PFOS exposure causes pathological changes in cardiac tissue and increases cardiac injury markers brain natriuretic peptide (BNP), lactate dehydrogenase (LDH), C-reactive protein (CRP) in serum and triglyceride (TG), total cholesterol (TC) and ox-LDL in plasma. Increased expression of plasminogen activator inhibitor-1 (PAI-1) and CD36 indicates that PFOS exacerbates cardiac fibrosis. Untargeted metabolites analysis revealed 414 small molecule metabolites and 33 metabolites that differed after PFOS exposure, and identified 3 potential metabolic pathways. In conclusion, our study shows the inflammatory reactions involved in PFOS cardiotoxicity, and identifies potential pathways and differential metabolites involved in PFOS toxicity.
ABSTRACT
Objectives: TANK-binding kinase 1 (TBK1) is pivotal in autoimmune and inflammatory diseases, yet its role in osteoarthritis (OA) remains elusive. This study sought to elucidate the effect of the TBK1 inhibitor BX795 on OA and to delineate the underlying mechanism by which it mitigates OA. Methods: Interleukin-1 Beta (IL-1ß) was utilized to simulate inflammatory responses and extracellular matrix degradation in vitro. In vivo, OA was induced in 8-week-old mice through destabilization of the medial meniscus surgery. The impact of BX795 on OA was evaluated using histological analysis, X-ray, micro-CT, and the von Frey test. Additionally, Western blot, RT-qPCR, and immunofluorescence assays were conducted to investigate the underlying mechanisms of BX795. Results: Phosphorylated TBK1 (P-TBK1) levels were found to be elevated in OA knee cartilage of both human and mice. Furthermore, intra-articular injection of BX795 ameliorated cartilage degeneration and alleviated OA-associated pain. BX795 also counteracted the suppression of anabolic processes and the augmentation of catabolic activity, inflammation, and senescence observed in the OA mice. In vitro studies revealed that BX795 reduced P-TBK1 levels and reversed the effects of anabolism inhibition, catabolism promotion, and senescence induction triggered by IL-1ß. Mechanistically, BX795 inhibited the IL-1ß-induced activation of the cGAS-STING and TLR3-TRIF signaling pathways in chondrocytes. Conclusions: Pharmacological inhibition of TBK1 with BX795 protects articular cartilage by inhibiting the activation of the cGAS-STING and TLR3-TRIF signaling pathways. This action attenuates inflammatory responses and cellular senescence, positioning BX795 as a promising therapeutic candidate for OA treatment. The translational potential of this article: This study furnishes experimental evidence and offers a potential mechanistic explanation supporting the efficacy of BX795 as a promising candidate for OA treatment.
ABSTRACT
PbSn solders are used in semiconductor devices for aerospace or military purposes with high levels of reliability requirements. Microalloying has been widely adopted to improve the reliability for Pb-free solders, but its application in PbSn solders is scarce. In this article, the optimization of PbSn solder reliability with Ge microalloying was investigated using both experimental and calculation methods. Intermetallic compounds (IMC) growth and morphologies evolution during reliability tests were considered to be the main factors of device failure. Through first-principle calculation, the growth mechanism of interfacial Ni3Sn4 was discussed, including the formation of vacancies, the Ni-vacancies exchange diffusion and the dominant Ni diffusion along the [1 0 0] direction. The doping of Ge in the cell increased the exchange energy barrier and thus inhibited the IMC development and coarsening trend. In three reliability tests, only 0.013 wt% Ge microalloying in Pb60Sn40 was able to reduce IMC thickness by an increment of 22.6~38.7%. The proposed Ge microalloying method in traditional PbSn solder could yield a prospective candidate for highly reliable applications.
ABSTRACT
Lipid synthesis is regulated by the actions of Scap, a polytopic membrane protein that binds cholesterol in membranes of the endoplasmic reticulum (ER). When ER cholesterol levels are low, Scap activates SREBPs, transcription factors that upregulate genes for synthesis of cholesterol, fatty acids, and triglycerides. When ER cholesterol levels rise, the sterol binds to Scap, triggering conformational changes that prevent activation of SREBPs and halting synthesis of lipids. To achieve a molecular understanding of how cholesterol regulates the Scap/SREBP machine and to identify therapeutics for dysregulated lipid metabolism, cholesterol-mimetic compounds that specifically bind and inhibit Scap are needed. To accomplish this goal, we focused on Anthrolysin O (ALO), a pore-forming bacterial toxin that binds cholesterol with a specificity and sensitivity that is uncannily similar to Scap. We reasoned that a small molecule that would bind and inhibit ALO might also inhibit Scap. High-throughput screening of a ~300,000-compound library for ALO-binding unearthed one molecule, termed UT-59, which binds to Scap's cholesterol-binding site. Upon binding, UT-59 triggers the same conformation changes in Scap as those induced by cholesterol and blocks activation of SREBPs and lipogenesis in cultured cells. UT-59 also inhibits SREBP activation in the mouse liver. Unlike five previously reported inhibitors of SREBP activation, UT-59 is the only one that acts specifically by binding to Scap's cholesterol-binding site. Our approach to identify specific Scap inhibitors such as UT-59 holds great promise in developing therapeutic leads for human diseases stemming from elevated SREBP activation, such as fatty liver and certain cancers.