Single-Cell Transcriptomics Reveals Longevity Immune Remodeling Features Shared by Centenarians and Their Offspring.

Centenarians, who show mild infections and low incidence of tumors, are the optimal model to investigate healthy aging. However, longevity related immune characteristics has not been fully revealed largely due to lack of appropriate controls. In this study, single-cell transcriptomic analysis of peripheral blood mononuclear cells (PBMCs) derived from seven centenarians (CEN), six centenarians' offspring (CO), and nine offspring spouses or neighbors (Control, age-matched to CO) are performed to investigate the shared immune features between CEN and CO. The results indicate that among all 12 T cell clusters, the cytotoxic-phenotype-clusters (CPC) and the naïve-phenotype-clusters (NPC) significantly change between CEN and ontrol. Compared to Control, both CEN and CO are characterized by depleted NPC and increased CPC, which is dominated by CD8+ T cells. Furthermore, CPC from CEN and CO share enhanced signaling pathways and transcriptional factors associated with immune response, and possesse similar T-cell-receptor features, such as high clonal expansion. Interestingly, rather than a significant increase in GZMK+ CD8 cells during aging, centenarians show accumulation of GZMB+ and CMC1+ CD8 T cells. Collectively, this study unveils an immune remodeling pattern reflected by both quantitative increase and functional reinforcement of cytotoxic T cells which are essential for healthy aging.

Serum Fibroblast Growth Factor 19 and Total Bile Acid Concentrations Are Potential Biomarkers of Hepatocellular Carcinoma in Patients with Type 2 Diabetes Mellitus.

PURPOSE: Type 2 diabetes mellitus (T2DM) carries a high risk of hepatocellular carcinoma (HCC). Both serum fibroblast growth factor 19 (FGF19) and bile acid concentrations are associated with T2DM and HCC. We aimed at evaluating the relationships between FGF19 and bile acid concentrations and HCC in patients with T2DM. METHODS: Twenty-seven healthy volunteers (control group), 27 patients with T2DM (T2DM group), 16 patients with newly diagnosed HCC (HCC group), and 10 T2DM patients with newly diagnosed HCC (T2DM-HCC group) were studied at the Affiliated Hospital of Nantong University between June 2016 and June 2017. The serum concentrations of serum FGF19 and total bile acids (TBA) were measured in all the participants. Correlation analysis and multiple stepwise regression analysis of the FGF19 and TBA concentrations were performed in all the participants and in the four groups. RESULTS: The concentrations of FGF19 were 220.5 pg/ml, 185.1 pg/ml, 115.8 pg/ml, and 70.4 pg/ml in the HCC, T2DM-HCC, control, and T2DM groups, respectively (p < 0.001), and the TBA concentrations were 21.75 µmol/l, 14.25 µmol/l, 14.25 µmol/l, 14.25 µmol/l, 14.25 p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 . CONCLUSIONS: Simultaneous increase of serum FGF19 and TBA levels may be used as indicators of HCC screening at early stage in patients with T2DM.

Absolute quantification of urinary neutrophil gelatinase-associated lipocalin by ultra-high-performance liquid chromatography/tandem mass spectrometry and the diagnostic efficacy of acute kidney injury.

RATIONALE: To establish an absolute quantification method for neutrophil gelatinase-associated lipocalin (NGAL) by ultra-high-performance liquid chromatography tandem positive ion electrospray ionization mass spectrometry (UHPLC/MS/MS) and evaluate its diagnostic efficacy for acute kidney injury (AKI). METHODS: Three target peptides of NGA were prescreened by Skyline software, and two of them could be detected in tryptic peptides of NGAL recombinant protein and human urinary NGAL (uNGAL). Peptide (WYVVGLAGNAILR) was then selected as surrogate peptide. The corresponding isotope-labeled peptide as the internal standard was next synthesized. Quantification of uNGAL was based on equations of linear regression, and method validation was then conducted. The diagnostic efficacy of uNGAL for AKI was also evaluated using receiver operating characteristic curve (ROC) analysis. Lastly, the UHPLC/MS/MS and the particle-enhanced turbidimetric immunoassay (PETIA) methods for uNGAL quantification were compared. RESULTS: For the y9 and y10 product ions, the linear regression equations were y = 2.5519x-4.6955 (R2 = 0.994, P<.01) and y = 2.4619x-4.3 (R2 =0.993, P<.01), respectively, and both of the linear ranges were from 0.5 to 15 mg/L. The limits of detection and quantification were 0.037 mg/L and 0.081 mg/L, respectively. The recoveries were from 97.32% to 107.28% at different uNGAL levels, and the within- and between-day CVs for uNGAL quantification were from 0.22% to 7.65% and from 0.66% to 5.97%, respectively. The carryover rates of uNGAL were in the range of 0.70%-0.99%. The area under the ROC curve (AUC) of uNGAL was 0.96 (P<0.01), and the sensitivity and specificity of uNGAL for AKI diagnosis were 90.0% and 92.5%, respectively. In addition, the UHPLC/MS/MS and PETIA methods showed good agreement for uNGAL quantification (y = 0.7112x-0.0139, P = 0.34). CONCLUSIONS: The UHPLC/MS/MS method for uNGAL quantification has a wide linear range, high sensitivity, precision, and recovery, and low carryover rates, and uNGAL detected by this method had high sensitivity and specificity for AKI diagnosis.

Increased REDD1 facilitates neuronal damage after subarachnoid hemorrhage.

Regulated in development and DNA damage responses 1 (REDD1) is a highly conserved stress-response protein and can be induced by hypoxia/ischemia and DNA damage. However, it is not known whether REDD1 involves in neuronal damage caused by subarachnoid hemorrhage (SAH) that is known as one of the most important causes of disability and death worldwide. Here, we first found that SAH markedly induced the increase of REDD1 (35.467 ng/ml) in cerebrospinal fluid (CSF) of patients at acute stage (within 24 h from bleeding) compared to that of control (0.644 ng/ml). And, REDD1 level was positively correlated with severity of brain injuries (Hunt-Hess grade of SAH), but it showed an obvious decline at recovery stage 6.201 ng/ml (before discharge from hospital) because of good recovery. Moreover, it was found that the expression of REDD1 was significantly induced by hemolysate in a dose-dependent way in neurons. Knockdown of REDD1 by lentivirus encoded REDD1-shRNA could inhibit the neuronal apoptosis and LDH leakage caused by hemolysate. Importantly, the level of REDD1 in peripheral blood of SAH patients was significantly higher (4.364 ng/ml) than that of healthy persons (1.317 ng/ml) and also was positively correlated with that in CSF. Taken together, our findings provide the novel and direct evidence that REDD1 could play a critical role of process of neuronal damage caused by SAH, suggesting a new molecular target to protect brain function from SAH injury.

Decreased expression of long noncoding RNA XLOC_013703 promotes cell growth via NF-κB pathway in multiple myeloma.

Long noncoding RNAs (lncRNAs) are dysregulated in cancer and involved in oncogenic or tumor inhibitory processes. The aim of the study was to investigate the expression pattern of lncRNA XLOC_013703 in multiple myeloma (MM) and to evaluate its biological role and potential significance. We found that XLOC_013703 was significantly decreased in CD138 positive plasma cells and serum of MM patients compared to normal controls, and the decreased XLOC_013703 expression was correlated with ß2-MG, serum-free light chain (s-FLC) and revised international staging system. RNA-fluorescence in situ hybridization results revealed that XLOC_013703 was distributed both in the nucleus and in the cytoplasm of MM cells including H929, RPMI8226, and U266. Overexpression of XLOC_013703 inhibited the proliferation of U266 cells and blocked the cell cycle in G1 stage, thus contributing to MM cell apoptosis. By contrast, knockdown of XLOC_013703 promoted the growth of H929 cells. Western blot analysis confirmed that the expression of p-IκBα and nuclear P65 was substantially increased in shRNA transfection groups compared to control groups, whereas overexpression of XLOC_013703 reduced these expressions. In conclusion, we confirmed that the decreased expression of a novel lncRNA, XLOC_013703, in MM. XLOC_013703 was involved in MM cell survival and proliferation via nuclear factor-κB pathway which represents a potential therapeutic target for MM. © 2019 IUBMB Life, 71(9):1240-1251, 2019.

Elevated RTP801 promotes cell proliferation in non-small cell lung cancer.

Lung cancer, particularly non-small cell lung cancer (NSCLC), is one of main causes of mortality in cancer patients worldwide. It is necessary to seek effective biomarkers to improve diagnostic and therapeutic efficacies in human NSCLC. RTP801 is a stress-response protein that can be induced by many types of cellular stress such as hypoxia and DNA damage, produces different biological effects depending on cell type and context. Up to now, there is no direct evidence showing the expression and involvement of RTP801 in human NSCLC. Here, we found that the expression of RTP801 significantly increased in NSCLC tissues compared with that in normal lung and the level of RTP801 in peripheral blood of NSCLC patients was higher than that of healthy persons. Further study showed that knockdown of RTP801 induced by lentivirus encoded RTP801-shRNA markedly inhibited the proliferation of A549 and SW900 cells. Moreover, the inhibitor of PI3K significantly decreased the expression of RTP801 mRNA and protein and, at the same time, inhibited the proliferation of A549 and SW900 cells. Taken together, our study provides the novel and direct evidence that there is a close relationship between RTP801 and human NSCLC, and RTP801 can promote the proliferation of NSCLC cells which is regulated by PI3K signaling pathway, suggesting that RTP801 could be a potential biomarker for diagnosis and therapeutic target of human NSCLC. © 2018 IUBMB Life, 70(4):310-319, 2018.

Quantification of cystatin-C in human serum by stable isotope dilution liquid chromatography electrospray ionization tandem mass spectrometry.

Cystatin C (CysC)-based estimated glomerular filtration rate is an excellent marker for early diagnosis of Chronic Kidney Disease (CKD). Particle-enhanced nephelometric immunoassay (PENIA) and particle-enhanced turbidimetric immunoassay (PETIA) are commonly used methods for CysC quantification in clinical testing. However, both of them lack of specificity which mass spectrometry offers. In this paper, an isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) method was established for quantification of CysC in human serum. After CysC denaturation, reduction and alkylation of cysteine residues, trypsin was added for proteolytic digestion of CysC. Specific peptide ALDFAVGEYNK was selected as surrogates for intact CysC protein, then quantified CysC by stable isotope-labelled internal standard peptide A[13C615N]LDFAVGEYNK based on calibration curve method. The calibration curves were y=0.1565x-1.6715 (R2=0.988) and y=1.8785x-2.2497 (R2=0.991) for y9 and y6, respectively. The linear range was 0.1-10mg/L and 0.5-15mg/L for y9 and y6, respectively. The limit of quantification (LOQ) was 0.052mg/L. At different concentrations of CysC, the recoveries were in the range of 80.5%-93.7%, the intraday precisions were in the range of 0.3%-2.2%, and the inter-day precisions were in the range of 0.2%-2.8%. The results show that ID-LC-MS/MS and PETIA methods have higher consistency (y=0.8021x+0.6611, p=0.14), and the mean difference of the two methods was -0.29mg/L, and 95% of the individual difference values were in the range of -0.91mg/L-0.33mg/L.

Ginkgolide B Protects Neurons from Ischemic Injury by Inhibiting the Expression of RTP801.

RTP801 (also known as REDD1), a stress-related protein, is induced by several environmental stresses such as ischemia and cigarette smoke. Although ischemia can dramatically up-regulate RTP801 expression in brain ischemia, up to now, the exact relation between RTP801 and neuronal death in ischemia is poorly understood. In the current study, using oxygen and glucose deprivation as an in vitro ischemic model in primary cultured cortical neurons, we found that the expression of RTP801 increased progressively with prolongation of ischemic duration, in which the expression of RTP801 is positively correlated with the release of lactate dehydrogenase (LDH) in neurons, and knockdown of RTP801 promoted neuronal survival in ischemia-reperfusion. It was further found that ginkgolide B (GB) could significantly increase cell viability and decrease LDH release, and at the same time reduce the levels of RTP801 mRNA and protein in neurons after ischemia and reperfusion. Moreover, GB-induced reduction in expression of RTP801 was blocked by application of LY294002, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K). These results demonstrate that RTP801 could play a detrimental role on neurons in ischemia, and GB might protect neurons against ischemic injury by inhibiting RTP801 expression via PI3K pathway.