A facile fluorescence-coupling approach to visualizing leonurine uptake and distribution in living cells and Caenorhabditis elegans.

BACKGROUND: Caenorhabditis elegans (C. elegans) has been recognized for being a useful model organism in small-molecule drug screens and drug efficacy investigation. However, there remain bottlenecks in evaluating such processes as drug uptake and distribution due to a lack of appropriate chemical tools. PURPOSE: This study aims to prepare fluorescence-labeled leonurine as an example to monitor drug uptake and distribution of small molecule in C. elegans and living cells. METHODS: FITC-conjugated leonurine (leonurine-P) was synthesized and characterized by LC/MS, NMR, UV absorption and fluorescence intensity. Leonurine-P was used to stain C. elegans and various mammalian cell lines. Different concentrations of leonurine were tested in conjunction with a competing parent molecule to determine whether leonurine-P and leonurine shared the same biological targets. Drug distribution was analyzed by imaging. Fluorometry in microplates and flow cytometry were performed for quantitative measurements of drug uptake. RESULTS: The UV absorption peak of leonurine-P was 490∼495 nm and emission peak was 520 nm. Leonurine-P specifically bound to endogenous protein targets in C. elegans and mammalian cells, which was competitively blocked by leonurine. The highest enrichment levels of leonurine-P were observed around 72 h following exposure in C. elegans. Leonurine-P can be used in a variety of cells to observe drug distribution dynamics. Flow cytometry of stained cells can be facilely carried out to quantitatively detect probe signals. CONCLUSIONS: The strategy of fluorescein-labeled drugs reported herein allows quantification of drug enrichment and visualization of drug distribution, thus illustrates a convenient approach to study phytodrugs in pharmacological contexts.

Indoleamine 2, 3-dioxygenase 1 activation in macrophage exacerbates hepatic ischemia-reperfusion injury by triggering hepatocyte ferroptosis.

BACKGROUND: Hepatic Ischemia-reperfusion (I/R) injury, critical challenge in liver surgery and transplantation, exerts a significant impact on the prognosis and survival of patients. Inflammation and cell death play pivotal roles in pathogenesis of hepatic I/R injury. Indoleamine 2, 3-dioxygenase 1 (IDO-1), a key enzyme involved in the kynurenine pathway, has been extensively investigated for its regulatory effects on innate immune responses and cell ferroptosis. However, the precise involvement of IDO-1 in hepatic I/R injury remains unclear. METHODS: IDO-1 knockout mice were generated to establish a murine model of liver partial warm ischemia and reperfusion, while an in vitro Hypoxia/Reoxygenation (H/R) model was employed to simulate ischemia/reperfusion injury. RESULTS: The involvement of ferroptosis was observed to be involved in hepatic I/R injury, and effective mitigation of liver injury was achieved through the inhibition of ferroptosis. In the context of hepatic I/R injury, up-regulation of IDO-1 was found in macrophages exhibiting prominent M1 polarization and impaired efferocytosis. Deficiency or inhibition of IDO-1 alleviated hepatocytes ferroptosis and M1 polarization induced by hepatic I/R injury, while also enhancing M2 polarization and promoting efferocytosis in macrophages. Furthermore, depletion of macrophages attenuated ferroptosis in hepatocytes induced by hepatic I/R injury. CONCLUSION: This study highlights the crucial role of IDO-1 activation in macrophages in triggering ferroptosis in hepatocytes during hepatic ischemia-reperfusion injury. Our findings suggest that targeting IDO-1 could be a promising therapeutic strategy for mitigating hepatic I/R injury associated with liver surgery and transplantation.

Composition Regulation of Potassium Sodium Niobate Thin Films through Post-Annealing under Alkali Element Atmospheres.

Amorphous potassium sodium niobate (KNN) films were synthesized at 300 °C through the radio frequency magnetron sputtering method and subsequently crystallized by post-annealing at 700 °C in various alkali element atmospheres (Na and K). The as-deposited film is notably deficient in alkali metal elements, particularly K, whereas the loss of alkali elements in the films can be replenished through annealing in an alkali element atmosphere. By adjusting the molar ratio of Na and K in the annealing atmosphere, the ratio of Na/K in the resultant film varied, consequently suggesting the efficiency of this method on composition regulation of KNN films. Meanwhile, we also found that the physical characteristics of the films also underwent differences with the change of an annealing atmosphere. The films annealed in a high Na atmosphere exhibit large dielectric losses with limited piezoelectric vibration behavior, while annealing in a high K atmosphere reduces the dielectric losses and enhances the piezoelectric behavior. Furthermore, the results of vibration measurement demonstrated that the film annealed in a mixed powder of 25% Na2CO3 and 75% K2CO3 exhibits an optimal vibration displacement of ~400 pm under the sinusoidal excitation voltage of 8 V. This approach of altering the composition of KNN films through post-annealing may introduce the new concept of property design of KNN as well as other similar films.

Indoleamine 2,3-dioxygenase 1-mediated iron metabolism in macrophages contributes to lipid deposition in nonalcoholic steatohepatitis.

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a rapidly progressing chronic liver disease of global significance. However, the underlying mechanisms responsible for NASH remain unknown. Indoleamine 2,3-dioxygenase 1 (IDO1) has been recognized as essential factor in immune response and metabolic regulation. Here we aimed to investigate the functions and mechanisms of the IDO1 in macrophages on hepatic lipid deposition and iron metabolism in NASH. METHODS: The effect of IDO1 in NASH was evaluated by WT and IDO1-/- mice model fed with methionine/choline-deficient (MCD) diet in vivo. Macrophages scavenger clodronate liposomes (CL) and overexpressing of IDO1 in macrophages by virus were employed as well. Lipid deposition was assessed through pathological examination and lipid droplet staining, while iron levels were measured using an iron assay kit and western blotting. Primary hepatocytes and bone marrow-derived macrophages were treated with oleic acid/palmitic acid (OA/PA) to assess IDO1 expression via Oil Red O staining and immunofluorescence staining in vitro. RESULTS: Pathological images demonstrated that the increase of IDO1 exacerbated lipid accumulation in the livers of mice with MCD diet, while reduction of iron accumulation was observed in the liver and the serum of MCD-fed mice. Scavenging of macrophages effectively mitigated both lipid and iron accumulation. In addition, the deficiency of IDO1 in macrophages significantly mitigated lipid accumulation and iron overload in hepatic parenchymal cells. Finally, lentivirus-mediated overexpression of IDO1 in liver macrophages exacerbated hepatic steatosis and iron deposition in NASH. CONCLUSIONS: Our results demonstrated that effective inhibition of IDO1 expression in macrophages in NASH alleviated hepatic parenchymal cell lipid accumulation and iron deposition, which provided new insights for the future treatment of NASH.

Erchen decoction alleviates the progression of NAFLD by inhibiting lipid accumulation and iron overload through Caveolin-1 signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: A combination of 6 different Chinese herbs known as Erchen decoction (ECD) has been traditionally used to treat digestive tract diseases and found to have a protective effect against nonalcoholic fatty liver disease (NAFLD). Despite its efficacy in treating NAFLD, the precise molecular mechanism by which Erchen Decoction regulated iron ion metabolism to prevent disease progression remained poorly understood. AIM OF STUDY: Our study attempted to confirm the specific mechanism of ECD in reducing lipid and iron in NAFLD from the perspective of regulating the expression of Caveolin-1 (Cav-1). STUDY DESIGN: In our study, the protective effect of ECD was investigated in Palmitic Acid + Oleic Acid-induced hepatocyte NAFLD model and high-fat diet-induced mice NAFLD model. To investigate the impact of Erchen Decoction (ECD) on lipid metabolism and iron metabolism via mediating Cav-1 in vitro, Cav-1 knockdown cell lines were established using lentivirus-mediated transfection techniques. MATERIALS AND METHODS: We constructed NAFLD model by feeding with high-fat diet for 12 weeks in vivo and Palmitic Acid + Oleic Acid treatment for 24 h in vitro. The regulation of Lipid and iron metabolism results by ECD were detected by serological diagnosis, immunofluorescent and immunohistochemical staining, and western blotting. The binding ability of 6 small molecules of ECD to Cav-1 was analyzed by molecular docking. RESULTS: We demonstrated that ECD alleviated the progression of NAFLD by inhibiting lipid accumulation, nitrogen oxygen stress, and iron accumulation in vivo and in vitro experiments. Furthermore, ECD inhibited lipid and iron accumulation in liver by up-regulating the expression of Cav-1, which indicated that Cav-1 was an important target for ECD to exert its curative effect. CONCLUSIONS: In summary, our study demonstrated that ECD alleviated the accumulation of lipid and iron in NAFLD through promoting the expression of Cav-1, and ECD might serve as a novel Cav-1 agonist to treat NAFLD.

Application of the 'online assessment + FOBT at home' to improve participation and the efficacy of opportunistic screening for colorectal cancer: a retrospective cohort study.

BACKGROUND: Colorectal cancer (CRC) screening faces two major challenges: insufficient screening coverage and poor adherence. A smartphone applet named "Early Screening Assistant (ESA)" was developed to create an online risk-assessment and fecal occult blood test (FOBT) at home. This retrospective study was designed to evaluate whether the new CRC screening strategy can improve the colonoscopy participation rate (PR) and lesion detection rate (DR). METHODS: In total, 6194 individuals who accepted normal health examinations and CRC screening based on the ESA from June 2020 to May 2022 were assigned to the ESA group. Accordingly, 7923 inhabitants who only accepted normal health examinations were assigned to the control group. The colonoscopy PR and neoplastic lesion DR were then compared between the two groups. RESULTS: Overall, a higher proportion of subjects in the ESA group (285 of 6194 [4.6%]) completed colonoscopy than in the control group (126 of 7923, [1.6%]), p < 0.01). The neoplastic lesion DR also significantly increased in the ESA group (76 of 6194 [1.22%]) compared with the control group (15 of 7923 [0.19%]) (p < 0.01). The adjusted diagnostic sensitivity and specificity of the "Online assessment + FOBT at home" were 41.5% and 62.6% for neoplastic lesions, respectively. CONCLUSIONS: This retrospective cohort study confirmed that the new CRC screening strategy based on the "Online assessment + FOBT at home" can improve colonoscopy participation and the neoplastic lesion detection rate and may represent a promising screening strategy for CRC. TRIAL REGISTRATION: This study was registered in China Clinical Trial Registry ( https://www.chictr.org.cn ) on 29/09/2022. REGISTRATION NUMBER: ChiCTR2200064186.