Rationale:Obese individuals are at high risk for developing atherosclerosis primarily attributable to elevated plasma concentrations of apolipoprotein (apo)B-containing particles, including very-low-density lipoprotein (VLDL). Plasma levels of the adipose tissue adipokine resistin are increased in human obesity, and resistin expression is positively correlated with coronary atherosclerosis and VLDL levels.Objective: We sought to determine for the first time whether resistin directly stimulates human hepatocyte production of apoB-containing particles and to elucidate the mechanisms responsible. Methods and Results:Treatment of human hepatocytes with resistin at levels observed in human obesity stimulated apoB secretion up to 10-fold, because of increased microsomal triglyceride transfer protein (MTP) activity and decreased expression/phosphorylation of proteins in the insulin signaling pathways (insulin receptor substrate-2, Akt, and extracellular signal-regulated kinase). Resistin also increased hepatocyte lipid content by stimulating de novo lipogenesis via the SREBP1 and SREBP2 pathways. Furthermore, obese serum with elevated resistin levels induced greater hepatocyte stimulation of apoB secretion than lean human serum, an effect that was ameliorated by antibody immunoprecipitation removal of serum resistin. Key Words: obesity Ⅲ dyslipidemia Ⅲ apolipoprotein B Ⅲ hepatic T he worldwide prevalence of obesity has reached epidemic proportions, with more than 1 billion individuals worldwide characterized as being obese. 1 In North America alone, 1 in 3 adults is obese. 2 This is a problem because obese individuals are at greatly elevated risk for developing atherosclerotic cardiovascular disease (ASCVD), the leading cause of death in North America. 3 Fundamental to the accelerated rate of ASCVD development in obese individuals is the presence of dyslipidemia. Despite numerous advances in the treatment of dyslipidemia, up to 60% of abdominally obese individuals have metabolic dyslipidemia: an elevation in plasma levels of triglycerides, a reduction in plasma high-density lipoprotein (HDL) cholesterol, and an increase in plasma numbers of low-densitylipoprotein (LDL) particles, which are small and dense. 4,5 The primary lipoprotein abnormality that drives the development of metabolic dyslipidemia in obesity is an elevation in plasma levels of very-low-density-lipoprotein (VLDL), which precedes and is metabolically linked to each component of metabolic dyslipidemia. 6,7 Elevated VLDL in obesity is primarily attributable to increased hepatic secretion of VLDL triglycerides and apolipoprotein (apo)B. 6,7 Although several mechanisms have been proposed, including whole-body and hepatic insulin resisOriginal received December 9, 2010; revision received January 20, 2011; accepted January 24, 2011. In December 2010, the average time from submission to first decision for all original research papers submitted to Circulation Research was 14.5 days. tance and increased free fatty acid (FFA) flux to the liver, these factor...
Wilms tumor (WT) is the most common childhood kidney cancer and retains gene expression profiles reminiscent of the embryonic kidney. We have shown previously that CITED1, a transcriptional regulator that labels the self-renewing, multipotent nephron progenitor population of the developing kidney, is robustly expressed across all major WT disease and patient characteristics. In this malignant context, CITED1 becomes enriched in the nucleus, which deviates from its cytosolic predominance in embryonic nephron progenitors. We designed the current studies to test the functional and mechanistic effects of differential CITED1 subcellular localization on WT behavior. To mimic its subcellular distribution observed in clinical WT specimens, CITED1 was misexpressed ectopically in the human WT cell line, WiT49, as either a wild-type (predominantly cytosolic) or a mutant, but transcriptionally active, protein (two point mutations in its nuclear export signal, CITED1ΔNES; nuclear-enriched). In vitro analyses showed that CITED1ΔNES enhanced WiT49 proliferation and colony formation in soft agar relative to wild-type CITED1 and empty vector controls. The nuclear-enriched CITED1ΔNES cell line showed the greatest tumor volumes after xenotransplantation into immunodeficient mice (n=15 animals per cell line). To elucidate CITED1 gene targets in this model, microarray profiling showed that wildtype CITED1 foremost upregulated LGR5 (stem cell marker), repressed CDH6 (early marker of epithelial commitment of nephron progenitors), and altered expression of specific WNT pathway participants. In summary, forced nuclear enrichment of CITED1 in a human WT cell line appears to enhance tumorigenicity, whereas ectopic cytosolic expression confers stem-like properties and an embryonic phenotype, analogous to the developmental context.
Inflammation is known as an important mechanism of cognitive dysfunction. Systemic immune inflammation index (SII) and system inflammation response index (SIRI) are two blood inflammatory markers, which are related to many chronic diseases including cognitive impairment. It is recognized that dietary inflammatory index (DII), which is used to estimate the overall inflammatory potential of diet, may be related to mild cognitive impairment (MCI) as well. This study aimed to explore the relationship between SII, SIRI and DII, as well as the role of these inflammatory indexes on MCI in elderly people. A total of 1050 participants from Beijing were included. Neuropsychological tests were used for cognitive evaluation. Energy-adjusted DII scores were calculated based on semi-quantitative food frequency questionnaire. Blood samples were tested for calculating SII and SIRI. Log-binomial regression models were used to estimate the correlation of indexes. After adjusting demographic characteristics, SII and SIRI in MCI individuals were higher than controls (p ≤ 0.001). DII, SII and SIRI had positive relationship with MoCA scores (p < 0.005). DII also correlated with SIRI in MCI (β = 0.11, p = 0.031). Higher DII and SIRI could definitely increase the risk of MCI, as well as DII and SII (p < 0.005). In conclusion, DII was positively correlated with blood inflammation. The elderly with higher level of DII and SIRI, or DII and SII could be considered as people with higher risk of developing MCI.
β-carotene is widely available in plant-based foods, while the efficacy of β-carotene supplementation on cardiovascular disease (CVD) risk remains controversial. Hence, we performed a systematic review and meta-analysis on randomized controlled trials to investigate the associations between β-carotene supplementation and CVD risk as well as mortality. We conducted literature searches across eight databases and screened the publications from January 1900 to March 2022 on the topic of β-carotene treatments and cardiovascular outcomes. There were 10 trials and 16 reports included in the meta-analysis with a total of 182,788 individuals enrolled in the study. Results from the random-effects models indicated that β-carotene supplementation slightly increased overall cardiovascular incidence (RR: 1.04; 95% CI: 1.00, 1.08) and was constantly associated with increased cardiovascular mortality (RR: 1.12; 95% CI: 1.04, 1.19). Subgroup analyses suggested that, when β-carotene treatments were given singly, a higher risk of cardiovascular outcomes was observed (RR: 1.06; 95% CI: 1.01, 1.12). In addition, cigarettes smoking was shown to be a risk behavior associated with increased cardiovascular incidence and mortality in the β-carotene intervention group. In sum, the evidence of this study demonstrated that β-carotene supplementation had no beneficial effects on CVD incidence and potential harmful effects on CVD mortality. Further studies on understanding the efficacy of multivitamin supplementation in nutrient-deficient or sub-optimal populations are important for developing the tolerable upper intake level for β-carotene of different age and sex groups.
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