Pharmacokinetics of Rhodamine 110 and Its Organ Distribution in Rats

Rhodamine dyes have been banned as food additives due to their potential tumorigenicity. Rhodamine 110 is illegal as a food additive, although its pharmacokinetics have not been characterized, and no accurate bioanalytical methods are available to quantify rhodamine 110. The aim of this study was to develop and validate a fast, stable, and sensitive method to quantify rhodamine 110 using high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) to assess its pharmacokinetics and organ distribution in awake rats. Rhodamine 110 exhibited linear pharmacokinetics and slow elimination after oral administration. Furthermore, its oral bioavailability was approximately 34–35%. The distribution in the liver and kidney suggests that these organs are primarily responsible for rhodamine 110 metabolism and elimination. Our investigation describes the pharmacokinetics and a quantification method for rhodamine 110, improving our understanding of the food safety of rhodamine dyes

CXCL9 Associated with Sustained Virological Response in Chronic Hepatitis B Patients Receiving Peginterferon Alfa-2a Therapy: A Pilot Study

<div><p>Background and Aims</p><p>There is lack of a practical biomarker to predict sustained virological response (SVR) in chronic hepatitis B (CHB) patients undergoing peginterferon alfa-2a (PEG-IFN). The aim of this pilot study was to identify immunological features associated with SVR.</p> <p>Methods</p><p>Consecutive 74 CHB patients receiving 24 weeks (for hepatitis B e antigen (HBeAg)-positive) or 48 weeks (for HBeAg-negative) PEG-IFN, were prospectively enrolled. Serum HBV viral loads, hepatitis B surface antigen (HBsAg), CXCL9, IFN-γ-inducible protein 10 (IP-10), interferon-gamma (IFN-γ) and transforming growth factor beta (TGF-β) were measured at baseline and week 12. SVR was defined as HBeAg seroconversion combined with viral load <2000 IU/mL in HBeAg-positive (n=36), and viral load <2000 IU/mL in HBeAg-negative patients (n=38) at 48 weeks after the end of treatment.</p> <p>Results</p><p>Nineteen patients (25.7%), 7 in HBeAg-positive and 12 in HBeAg-negative, achieved SVR. There were significant declines of HBV DNA, HBsAg, IP-10 and IFN-γ levels at week 12. In multivariate analysis, pre-treatment CXCL9 >80 pg/mL, HBV DNA <2.5 x 10⁷ IU/mL and on-treatment HBV viral load, HBsAg decline >10% at week 12 were predictors of SVR. The performance of CXCL9 in predicting SVR was good in patients with HBV DNA <2.5 x 10⁷ IU/mL, particularly in HBeAg-negative CHB cases (positive predictive value, PPV= 64.3%).</p> <p>Conclusions</p><p>Pre-treatment CXCL9 level has the potential to select CHB patients who can respond to PEG-IFN, especially in HBeAg-negative patients with low viral loads.</p> </div

Kinetics of serum CXCL9 levels during PEG-IFN treatment in CHB patients with or without SVR.

<p>In patients with SVR, CXCL9 levels significantly decreased from baseline to week 12, whereas in patients without SVR, CXCL9 levels remained high at week 12 but decreased later from week 12 to EOT. Data were presented as mean ± standard errors of the means (SEM). EOT: end of treatment.</p

Correlations between serum ALT and chemokine levels.

<p>(A) A positive correlation between CXCL9 and ALT; (B). A positive correlation between IP-10 and ALT. Concentrations of serum ALT, CXCL9 and IP-10 levels were collected at each time point during PEG-IFN treatment (overall n=232).</p

Concentration-response curves to AVP in portal-systemic collateral vascular beds.

<p>(A) Concentration-response curves of BDL and BDL/STZ rats. BDL: vehicle injection; BDL/STZ: STZ injection; K: Krebs solution; G: D-glucose, expressed as absolute increase over baseline value. Concentration-response curves of the BDL/STZ/K group were significantly weaker than that of the BDL/K and BDL/G groups (mean±SDM). (B) Concentration-response curves of BDL/STZ rats. K: Krebs solution; G: D-glucose; OPC-31260: OPC-31260, expressed as absolute increase over baseline value. Concentration-response curves of the BDL/STZ/OPC-31260 group were significantly higher in 10⁻⁷ M AVP than that of the BDL/STZ/K and BDL/STZ/G groups.</p

V_1aR, V₂R and G_α-protein mRNA expressions in splenorenal shunts of BDL or BDL/STZ rats.

<p>(A) BDL: vehicle injection; BDL/STZ: STZ injection; K: Krebs solution. V_1aR mRNA expression level was not significantly different between BDL/K and BDL/STZ/K groups. V₂R mRNA expression was significantly lower of the BDL/K group than that of the BDL/STZ/K group. (B) G_α-protein expressions and their relationship with the maximal AVP responsiveness. BDL: vehicle injection; BDL/STZ: STZ injection; K: Krebs solution. Compared to BDL/K group, G_αq, G_α11, G_αs and G_αi mRNA expression levels were all significantly decreased in the BDL/STZ/K group (<i>P</i><0.05). The maximal perfusion pressure change to AVP was positively correlated with G_αq (<i>P</i> = 0.002, R = 0.550) and G_α11 expression (<i>P</i> = 0.039, R = 0.392).</p

Study design.

<p>Study design.</p

Maximum increase of perfusion pressure and EC50 in BDL rats with STZ injection.

†<p>: <i>P</i><0.01 vs. BDL/STZ/G+NaF rat; *: <i>P</i><0.01 vs. BDL/G+NaF rat.</p

Primers of target and housekeeping genes used for RT-PCR.

<p>Primers of target and housekeeping genes used for RT-PCR.</p

The Role of Interferon-γ Inducible Protein-10 in a Mouse Model of Acute Liver Injury Post Induced Pluripotent Stem Cells Transplantation

<div><h3>Background</h3><p>Liver injuries are important medical problems that require effective therapy. Stem cell or hepatocyte transplantation has the potential to restore function of the damaged liver and ameliorate injury. However, the regulatory factors crucial for the repair and regeneration after cell transplantation have not been fully characterized. Our study investigated the effects and the expression of the regulatory factors in mouse models of acute liver injury either transplanted with the induced pluripotent stem cells (iPS) or the hepatocytes that differentiated from iPS cells (iHL).</p> <h3>Methods/Principal Findings</h3><p>Mice received CCl₄ injection and were randomized to receive vehicle, iPS, or iHL transfusions vial tail veins and were observed for 24, 48 or 72 hours. The group of mice with iPS transplantation performed better than the group of mice receiving iHL in reducing the serum alanine aminotransferase, aspartate aminotransferase, and liver necrosis areas at 24 hours after CCl₄ injury. Moreover, iPS significantly increased the numbers of proliferating hepatocytes at 48 hours. Cytokine array identified that chemokine IP-10 could be the potential regulatory factor that ameliorates liver injury. Further studies revealed that iPS secreted IP-10 <em>in vitro</em> and transfusion of iPS increased IP-10 protein and mRNA expressions in the injured livers <em>in vivo</em>. The primary hepatocytes and non-parenchyma cells were isolated from normal and injured livers. Hepatocytes from injured livers that received iPS treatment expressed more IP-10 mRNA than their non-hepatocyte counter-parts. In addition, animal studies revealed that administration of recombinant IP-10 (rIP-10) effectively reduced liver injuries while IP-10-neutralizing antibody attenuated the protective effects of iPS and decreased hepatocyte proliferation. Both iPS and rIP-10 significantly reduced the 72-hour mortality rate in mice that received multiple CCl₄-injuries.</p> <h3>Conclusions/Significance</h3><p>These findings suggested that IP-10 may have an important regulatory role in facilitating the repair and regeneration of injured liver after iPS transplantation.</p> </div