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BACKGROUND & AIMS:The interferon (IFN) system plays a critical role in innate antiviral response. We presume that targeted induction of IFN in human liver shows robust antiviral effects on hepatitis C virus (HCV) and hepatitis B virus (HBV). METHODS:This study used chimeric mice harboring humanized livers and infected with HCV or HBV. This mouse model permitted simultaneous analysis of immune responses by human and mouse hepatocytes in the same liver and exploration of the mechanism of antiviral effect against these viruses. Targeted expression of IFN was induced by treating the animals with a complex comprising a hepatotropic cationic liposome and a synthetic double-stranded RNA analog, pIC (LIC-pIC). Viral replication, IFN gene expression, IFN protein production, and IFN antiviral activity were analyzed (for type I, II and III IFNs) in the livers and sera of these humanized chimeric mice. RESULTS:Following treatment with LIC-pIC, the humanized livers of chimeric mice exhibited increased expression (at the mRNA and protein level) of human IFN-λs, resulting in strong antiviral effect on HBV and HCV. Similar increases were not seen for human IFN-α or IFN-β in these animals. Strong induction of IFN-λs by LIC-pIC occurred only in human hepatocytes, and not in mouse hepatocytes nor in human cell lines derived from other (non-hepatic) tissues. LIC-pIC-induced IFN-λ production was mediated by the immune sensor adaptor molecules mitochondrial antiviral signaling protein (MAVS) and Toll/IL-1R domain-containing adaptor molecule-1 (TICAM-1), suggesting dual recognition of LIC-pIC by both sensor adaptor pathways. CONCLUSIONS:These findings demonstrate that the expression and function of various IFNs differ depending on the animal species and tissues under investigation. Chimeric mice harboring humanized livers demonstrate that IFN-λs play an important role in the defense against human hepatic virus infection.

Context: Chronic kidney disease (CKD) is a worldwide health problem. Recent literature has shown an association of hemoglobin glycation index (HGI) and CKD in patients with dysglycemia. Objective: The aim of this study was to reveal the impact of HGI as a predictor for incident CKD in the general population. Methods: CKD was defined as dipstick proteinuria or estimated glomerular rate (eGFR) < 60 mL/min/1.73 m². Impact of HGI on incident CKD was assessed using the data from CKD-free health examinees (N = 23 467, 4.1% with diabetes) followed for a mean of 5.1 years: Cox proportional hazards model was employed with multivariate adjustment for age, systolic blood pressure, eGFR, fasting plasma glucose, body mass index, log[alanine aminotransferase], log[triglycerides], high-density lipoprotein cholesterol, platelet counts, smoking, and sex. Elevated level of HGI in subjects with CKD was ascertained after propensity score matching of another group of health examinees (N = 2580, 7.6% with diabetes). Results: In the former group, CKD developed in 2540 subjects and HGI was the second most robust predictor for CKD, following low eGFR. With adjustment for the 11 covariates, the hazard ratio of HGI (95% CI) for CKD was 1.293 (1.238 to 1.349) (P < .0001). The population attributable risk of HGI for CKD was 4.2%. In the latter group, among 708 subjects matched 1:1 for 9 covariates, HGI was significantly elevated in subjects with CKD (median [interquartile range] −0.208 [−0.504 to −0.156] vs −0.284 [−0.582 to 0.052], P = .03). Conclusion: HGI was a novel risk factor for CKD in the general population [ABSTRACT FROM AUTHOR]

The trajectory of glomerular filtration rate (GFR) in relation to glomerular hyperfiltration (GHF) has been unknown. It was evaluated retrospectively in 23,982 GHF-free health examinees who were followed for 2−10 yr (mean: 5.1 yr). GFR was estimated by the serum creatinine concentration, and GHF was defined as age- and sex-specific estimated GFR (eGFR) ≥ 95% of the Japanese general population. The temporal profile of eGFR was plotted in a GHF-centered way, which was fitted to a random coefficient linear mixed model. Of the 23,982 subjects, 797 and 23,185 subjects developed or did not develop GHF, respectively, so that they were termed as the GHF(+) and GHF(−) groups. At baseline, median eGFR was significantly elevated in the GHF(+) group compared with in the GHF(−) group: 94.1 versus 77.3 mL/min/1.73 m2 (P < 0.001). Elevation of basal eGFR lasted for a mean (SD) of 3.3 (1.9) yr in the GHF(+) group; mean eGFR then rose to the GHF range, which was 108.5 mL/min/1.73 m2. The eGFR decline after the peak was steeper in the GHF(+) group than in the GHF(−) group: −0.984 versus −0.497 mL/min/1.73 m2/yr (P < 0.001). Baseline eGFR, but no other variable, well predicted incident GHF, with an area under the receiver operating characteristic curve of 0.87 (95% confidence interval: 0.86–0.88). In conclusion, GHF occurs as a chronic, multiphasic phenomenon: initially with a sustained GFR elevation for years, followed by a GFR surge to the GHF range, which was accompanied by accelerated GFR declining. [ABSTRACT FROM AUTHOR]

A hypothesis that postchallenge hyperglycemia in subjects with low body weight (BW) may be due, in part, to small glucose volume (GV) was tested. We studied 11,411 nondiabetic subjects with a mean BW of 63.3 kg; 5,282 of them were followed for a mean of 5.3 yr. In another group of 1,537 nondiabetic subjects, insulin sensitivity, secretion, and a product of the two (index of whole body insulin action) were determined. Corrected 2 h-plasma glucose (2hPGcorr) during a 75-g oral glucose tolerance test in subjects with BW ≤ 59 kg was calculated as 2hPGcorr = δPG2h · ECW/[16.1 (males) or 15.3 (females)] + fasting PG (FPG), where δPG2h is plasma glucose increment in 2 h; ECW is extracellular water (surrogate of GV); FPG is fasting plasma glucose; and 16.1 and 15.3 are ECW of men and women, respectively, with BW = 59 kg. Multivariate analyses for BW with adjustment for age, sex, and percent body fat were undertaken. BW was, across its entire range, positively correlated with FPG (P < 0.01). Whereas BW was correlated with 2hPG and δPG in a skewed J-shape, with inflections at around 60 kg (P for nonlinearity < 0.01 for each). Nonetheless, in those with BW ≤ 59 kg, insulin sensitivity, secretion, and action were unattenuated, and incident diabetes was less compared with heavier counterparts. BW was linearly correlated with 2hPGcorr, i.e., the J-shape correlation was mitigated by the correction. In conclusion, postchallenge hyperglycemia in low BW subjects is in part due to small GV rather than impaired glucose metabolism. [ABSTRACT FROM AUTHOR]