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Background The increasing prevalence of heated tobacco products (HTPs) has heightened concerns regarding their potential health risks. Previous studies have demonstrated the toxicity of cigarette smoke extract (CSE) from traditional tobacco's mainstream smoke, even after the removal of nicotine and tar. Our study aimed to investigate the cytotoxicity of CSE derived from HTPs and traditional tobacco, with a particular focus on the role of reactive oxygen species (ROS) and intracellular Ca.sup.2+. Methods A human oral squamous cell carcinoma (OSCC) cell line, HSC-3 was utilized. To prepare CSE, aerosols from HTPs (IQOS) and traditional tobacco products (1R6F reference cigarette) were collected into cell culture media. A cell viability assay, apoptosis assay, western blotting, and Fluo-4 assay were conducted. Changes in ROS levels were measured using electron spin resonance spectroscopy and the high-sensitivity 2ʹ,7ʹ-dichlorofluorescein diacetate assay. We performed a knockdown of calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) by shRNA lentivirus in OSCC cells. Results CSE from both HTPs and traditional tobacco exhibited cytotoxic effects in OSCC cells. Exposure to CSE from both sources led to an increase in intracellular Ca.sup.2+ concentration and induced p38 phosphorylation. Additionally, these extracts prompted cell apoptosis and heightened ROS levels. N-acetylcysteine (NAC) mitigated the cytotoxic effects and p38 phosphorylation. Furthermore, the knockdown of CaMKK2 in HSC-3 cells reduced cytotoxicity, ROS production, and p38 phosphorylation in response to CSE. Conclusion Our findings suggest that the CSE from both HTPs and traditional tobacco induce cytotoxicity. This toxicity is mediated by ROS, which are regulated through Ca.sup.2+ signaling and CaMKK2 pathways. Graphical Abstract Keywords: Heated tobacco products (HTPs), Calcium, Oral cancer, Calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2), Reactive oxygen species (ROS), Author(s): Nagao Kagemichi[sup.1,2], Masanari Umemura[sup.1], Soichiro Ishikawa[sup.1,3], Yu Iida[sup.1,2], Shota Takayasu[sup.1], Akane Nagasako[sup.1], Rina Nakakaji[sup.1,3], Taisuke Akimoto[sup.2], Makoto Ohtake[sup.2], Takahiro Horinouchi[sup.4], Tetsuya Yamamoto[sup.2] and Yoshihiro Ishikawa[sup.1] Background Tobacco is responsible [...]

Background Sepsis-induced acute lung injury (ALI) accounts for about 40% of ALI, accompanied by alveolar epithelial injury. The study aimed to reveal the role of circular RNA_0114428 (circ_0114428) in sepsis-induced ALI. Methods Human pulmonary alveolar epithelial cells (HPAEpiCs) were treated with lipopolysaccharide (LPS) to mimic a sepsis-induced ALI cell model. RNA expression of circ_0114428, miR-574-5p and Rho-associated coiled-coil containing protein kinase 2 (ROCK2) was detected by qRT-PCR. Protein expression was checked by Western blotting. Cell viability, proliferation and apoptosis were investigated by cell counting kit-8, 5-Ethynyl-29-deoxyuridine (EdU) and flow cytometry analysis, respectively. The levels of pro-inflammatory factors were detected by enzyme-linked immunosorbent assay (ELISA). Oxidative stress was analyzed by lipid peroxidation Malondialdehyde (MDA) and Superoxide Dismutase (SOD) activity detection assays. The interplay among circ_0114428, miR-574-5p and ROCK2 was identified by dual-luciferase reporter, RNA pull-down and RNA immunoprecipitation assays. Results Circ_0114428 and ROCK2 expression were significantly increased, but miR-574-5p was decreased in blood samples from sepsis patients and LPS-stimulated HPAEpiCs. LPS treatment led to decreased cell viability and proliferation and increased cell apoptosis, inflammation and oxidative stress; however, these effects were relieved after circ_0114428 knockdown. Besides, circ_0114428 acted as a miR-574-5p sponge and regulated LPS-treated HPAEpiC disorders through miR-574-5p. Meanwhile, ROCK2 was identified as a miR-574-5p target, and its silencing protected against LPS-induced cell injury. Importantly, circ_0114428 knockdown inhibited ROCK2 production by interacting with miR-574-5p. Conclusion Circ_0114428 knockdown protected against LPS-induced HPAEpiC injury through miR-574-5p/ROCK2 axis, providing a novel therapeutic target in sepsis-induced ALI. Keywords: ALI, circ_0114428, miR-574-5p, ROCK2, LPS, Author(s): Jing Zhao[sup.1], Qin Zhao[sup.2] and Qiuxia Duan[sup.3] Introduction Developing as a result of immune response to pathogen-induced infection, sepsis is a complicated disorder with a high mortality rate of [...]

Theobromine, a methylxanthine present in cocoa, has been shown to possess many beneficial pharmacological properties such as anti-oxidative stress, anti-inflammatory property, and anti-microbial activity. In this study, we investigated the effects of theobromine on nonalcoholic fatty liver disease (NAFLD) and the possible underlying mechanisms in vivo and in vitro. The results showed that theobromine reduced body weight and fat mass and improved dyslipidemia. Theobromine mitigated liver injury and significantly reduced hepatic triglyceride level in mice with obesity. Histological examinations also showed hepatic steatosis was alleviated after theobromine treatment. Furthermore, theobromine reversed the elevated mRNA and protein expression of SREBP-1c, FASN, CD36, FABP4, and the suppressed expression of PPAR[alpha] and CPT1a in the liver of mice with obesity, which were responsible for lipogenesis, fatty acid uptake, and fatty acid oxidation respectively. In vitro, theobromine also downregulated SREBP-1c, FASN, CD36, FABP4 and upregulated PPAR[alpha] and CPT1a mRNA and protein levels in hepatocytes in a dose-dependent manner, while these changes were reversed by L-leucine, a mammalian target of rapamycin (mTOR) agonist. The present study demonstrated that theobromine improved NAFLD by inhibiting lipogenesis and fatty acid uptake and promoting fatty acid oxidation in the liver and hepatocytes, which might be associated with its suppression of mTOR signaling pathway. Novelty: * Theobromine protects against high-fat diet--induced NAFLD. * Theobromine inhibits lipogenesis and fatty acid uptake and promotes fatty acid oxidation in the liver and hepatocytes via inhibiting mTOR signaling pathway. Key words: nonalcoholic fatty liver disease, theobromine, mTOR, lipogenesis, fatty acid uptake, fatty acid oxidation. On a montre que la theobromine, une methylxanthine presente dans le cacao, est dotee de nombreuses proprietes pharmacologiques avantageuses entre autres contre le stress oxydatif et l'inflammation, avec une activite antimicrobienne. Cette etude porte sur les effets de la theobromine sur la steatose hepatique non alcoolique (SHNA) et les modes d'action in vivo et in vitro sous-jacents eventuels. Les resultats ont montre que la theobromine permet de faire diminuer la masse corporelle et la masse adipeuse, ainsi que d'attenuer la dyslipidemie. La theobromine permettait d'attenuer les lesions hepatiques et de faire diminuer les taux hepatiques de TG de facon marquee chez la souris obese. L'examen histologique a aussi montre que la steatose hepatique s'attenuait a la suite de l'administration de theobromine. En outre, la theobromine permettait d'inverser la hausse de l'expression en ARNm et en proteines de SREBP-1c, de FASN, de CD36 et de FABP4 ainsi que d'inhiber completement l'expression des PPAR[alpha] et de CPT1a dans le foie des souris obeses, expressions qui etaient responsables de la lipogenese, de la mobilisation des acides gras et de leur oxydation, respectivement. Dans les hepatocytes in vitro, la theobromine a aussi entraine une regulation a la baisse de SREBP-1c, de FASN, de CD36 et de FABP4 ainsi qu'une regulation a la hausse des PPAR[alpha] et de CPT1a en ARNm et en proteines de maniere proportionnelle a la dose, tandis que ces variations s'inversaient avec la L-leucine, un agoniste de mTOR. La presente etude a montre que la theobromine permettait d'attenuer la SHNA par l'intermediaire de l'inhibition de la lipogenese, de la mobilisation des acides gras et a la faveur de leur oxydation dans le foie et les hepatocytes, ce qui pourrait etre associe avec son inhibition complete de la voie de signalisation de mTOR. [Traduit par la Redaction] Nouveaute: * La theobromine assure une protection contre la SHNA provoquee par un regime alimentaire a teneur elevee en matieres grasses. * La theobromine permet d'inhiber la lipogenese et la mobilisation des acides gras ainsi que de favoriser l'oxydation des acides gras dans le foie et les hepatocytes par l'intermediaire de l'inhibition de la voie de signalisation de mTOR. Mots-cles: steatose hepatique non alcoolique, theobromine, mTOR, lipogenese, mobilisation des acides gras, oxydation des acides gras., Introduction Nonalcoholic fatty liver disease (NAFLD) is rapidly increasing and gradually becoming the most common chronic liver disease due to its strong relationship with obesity, type 2 diabetes mellitus (T2DM), [...]