Hyaluronic Acid Nanoparticles Based on a Conjugated Oligomer Photosensitizer: Target-Specific Two-Photon Imaging, Redox-Sensitive Drug Delivery, and Synergistic Chemo-Photodynamic Therapy.

Self-assembled hyaluronic acid (HA) nanoparticles have been extensively investigated as anticancer therapeutic agents due to the biocompatibility, biodegradability, and active targeting characteristics of HA. However, many HA nanoparticles are restricted to the applications in drug delivery for chemotherapy or lack effective imaging agents. Hence, we developed the camptothecin (CPT)-loaded HA-SS-BFVPBT nanoparticles (HSBNPs) as a multifunctional platform for two-photon imaging and synergistic chemo-photodynamic therapy at the same time. A novel conjugated oligomer photosensitizer, BFVPBT, which was conjugated onto HA through the redox-responsive disulfide linkage (SS), could not only provide a hydrophobic domain for the formation of nanoparticles and drug entrapment but also act as a two-photon photosensitizer that can be directly excited and simultaneously used in two-photon imaging and photodynamic therapy (PDT). HeLa cells overexpressing the HA receptor (CD44) were used for in vitro studies, which proved the specific cellular uptake of CPT-loaded HSBNPs and excellent two-photon PDT/chemotherapy synergistic effect. The nanoparticles have also been shown to realize tumor-targeting in vivo imaging in HeLa-tumor-bearing mice. Moreover, the fluorescence of CPT-loaded HSBNPs could be activated due to the degradation by the reductive glutathione (GSH) and overexpressed hyaluronidases (Hyal-1) in cancer cells, and the intracellular drug release rate was quickened, thus improving the probability of precise cancer diagnosis and therapy. Accordingly, this HSBNPs system is also anticipated to be a precise nanocarrier for other imaging and therapeutic agents besides CPT, offering a promising new avenue for imaging-guided efficient cancer therapy.

Hepatitis C virus core protein induces dysfunction of liver sinusoidal endothelial cell by down-regulation of silent information regulator 1.

Hepatic fibrosis is a frequent feature of chronic hepatitis C virus (HCV) infection. Some evidence has suggested the potential role of silent information regulator 1 (SIRT1) in organ fibrosis. The aim of this study was to investigate the effect of HCV core protein on expression of SIRT1 of liver sinusoidal endothelial cell (LSEC) and function of LSEC. LSECs were co-cultured with HepG2 cells or HepG2 cells expressing HCV core protein and LSECs cultured alone were used as controls. After co-culture, the activity and expression levels of mRNA and protein of SIRT1 in LSEC were detected by a SIRT1 fluorometric assay kit, real time-PCR (RT-PCR), Western blot, respectively. The levels of adiponectin receptor 2 (AdipoR2), endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) were measured by Western blot. Cluster of differentiation 31 (CD31), CD14, and von Willebrand factor (vWf) of LSECs was performed by flow cytometry. The level of reactive oxygen species (ROS) was assayed. Malondialdehyde (MDA), superoxide dismutase (SOD), adiponectin, nitric oxide (NO), and endothelin-1 (ET-1) levels in the co-culture supernatant were measured. The co-culture supernatant was then used to cultivate LX-2 cells. The levels of α-smooth muscle actin (ASMA) and transforming growth factor-ß1 (TGF-ß1) protein in LX-2 cells were measured by Western blot. Compared with LSEC co-cultured with HepG2 cells group, in LSEC co-cultured with HepG2-core cells group, the activity and expression level of mRNA and protein of SIRT1 reduced; the level of adiponectin reduced and the expression level of AdipoR2 protein decreased; ROS levels increased; the expression level of eNOS, VEGF protein decreased; and the expression level of CD14 decreased; the expression level of vWf and CD31 increased; NO and SOD levels decreased; whereas ET-1 and MDA levels increased; the levels of ASMA and TGF-ß1 protein in LX-2 cells increased. SIRT1 activator improved the above-mentioned changes. HCV core protein may down-regulate the activity and the expression of SIRT1 of LSEC, then decreasing synthesis of adiponectin and the expression of AdipoR2, thus inducing contraction of LSEC and hepatic sinusoidal capillarization and increasing oxidative stress, ultimately cause hepatic stellate cell (HSC) activation. Treatment with SIRT1 activator restored the function of LSEC and inhibited the activation of HSC.

Factors influencing the functional significance in intermediate coronary stenosis.

OBJECTIVE: To analyze the influencing factors of the functional significance determined by fractional flow reserve (FFR) in intermediate coronary artery stenosis. METHODS: The study enrolled 143 patients with 203 intermediate coronary lesions. Pressure-derived FFR of these lesions was gained at maximal hyperemia induced by intravenous adenosine infusion. An FFR < 0.80 was considered as abnormal functional significance. Anatomic parameters at the lesion sites were obtained by off-line quantitative coronary angiography analysis (QCA). The predictive value of the demographic characteristics and anatomic parameters for FFR in these intermediate lesions was assessed using multiple linear and binary logistic regression analysis. RESULTS: Overall, FFR < 0.8 was found in 70 (34%) of the total 203 intermediate coronary lesions. FFR values were positively correlated with QCA-measured minimum lumen diameters (MLD, r = 0.372, P = 0.000) and the reference vessel diameters (RVD, r = 0.217, P = 0.002) were negatively correlated with percent area stenosis (AS, r = -0.251, P = 0.000) and percent diameter stenosis (DS, r = -0.210, P = 0.000). Age, MLD and the lesion location in different coronary arteries were the independent determinants of FFR < 0.8. CONCLUSIONS: MLD can predict the functional significance of intermediate coronary stenosis, while age and the lesion location in different coronary arteries should be taken into account as important influencing factors of FFR values.

Hepatitis C virus core protein induces hepatic metabolism disorders through down-regulation of the SIRT1-AMPK signaling pathway.

BACKGROUND: Steatosis and insulin resistance induced by hepatitis C virus (HCV) infection are, at least in part, critical factors for the progression of chronic hepatitis C (CHC) and can influence the outcome of antiviral treatment. Silent information regulator 1 (SIRT1) and adenosine monophosphate-activated protein kinase (AMPK) play a key role in the regulation of hepatic glucose and lipid metabolism. The aim of this study was to investigate the possible effect of HCV core protein on energy, glucose, and lipid metabolism of hepatocytes and expression of SIRT1 and AMPK. METHODS: HCV core protein expression plasmid was transfected into HepG2 cells. The level of reactive oxygen species (ROS) and values of NAD(+)/NADH and ATP/ADP were detected. Intracellular levels of triacylglycerol (TG), cholesterol, glucose uptake by hepatocytes, and glucose production were measured. The expression levels of mRNA and protein of SIRT1 and AMPK were detected. The mRNA levels of SIRT1 and AMPK downstream glucose and lipid metabolism genes were measured. RESULTS: In HepG2 cells expressing HCV core protein, the level of ROS increased, the value of NAD(+)/NADH decreased, the activity and expression levels of mRNA and protein of SIRT1 and AMPK decreased, glucose uptake and its regulator gene GLUT2 mRNA levels decreased, glucose production and its regulator genes PEPCK and G6Pase mRNA levels increased, intracellular TG and cholesterol contents and their regulator gene (SREBP-1c, FAS, ACC, HMGR, and HMGS) mRNA levels increased, the glycolytic gene GK and fatty acid oxidation genes PPARα and CPT1A mRNA levels decreased. CONCLUSIONS: HCV core protein induces alterations in cellular redox state (decrease in the NAD(+)/NADH ratio), which could influence the activity of SIRT1 and secondarily AMPK, then change the expression profile of glucose and lipid metabolism-related genes, thereby causing metabolism disorders of hepatocytes.

Efficacy and factors influencing treatment with peginterferon alpha-2a and ribavirin in elderly patients with chronic hepatitis C.

BACKGROUND: In China, hepatitis C virus (HCV) infection is characterized by an increasing prevalence during aging. This study was undertaken to evaluate the efficacy of treatment with peginterferon alpha-2a and ribavirin in elderly chronic hepatitis C (CHC) patients and study the factors related to the sustained virologic response (SVR). METHODS: The medical records of 417 patients treated with peginterferon and ribavirin were retrospectively analyzed. These patients were divided into two groups according to age: patients aged ≥ 65 years (n=140) and patients aged <65 years (n=277). The rate of ribavirin reduction or discontinuation and virologic response rates of the two groups were compared. The factors influencing SVR were studied by multivariate analysis. RESULTS: Ribavirin reduction or discontinuation was more frequent in patients aged ≥ 65 years than patients aged <65 years (37.1%, 52/140 vs 20.2%, 56/277; X2=13.883, P<0.001). For genotype 1, patients aged ≥ 65 years had a higher relapse rate (50.0%, 42/84 vs 29.2%, 52/178; X2=10.718, P=0.001) and a lower SVR rate (40.0%, 42/105 vs 60.0%, 126/210; X2=11.250, P=0.001) than patients aged <65 years. There were no significant differences in virologic response rates between the two groups for patients with genotype 2. For genotype 1, in patients aged ≥ 65 years, the SVR rate of females was lower than that of males (28.6%, 12/42 vs 47.6%, 30/63; X2=8.150, P=0.004); in the high viral load group, patients aged ≥ 65 years had a lower SVR rate than patients aged <65 years (30.0%, 18/60 vs 54.8%, 69/126; X2=10.010, P=0.002). In multivariate logistic regression analysis, the independent factors associated with SVR in patients aged ≥ 65 years were sex (P=0.020), genotype (P=0.005), ribavirin reduction or discontinuation (P=0.009) and presence of rapid virologic response (RVR) (P=0.001). CONCLUSIONS: The rate of ribavirin reduction or discontinuation and relapse rate of patients aged ≥ 65 years with genotype 1 are high, and the SVR rate is low. Age has no impact on virologic responses rates for genotype 2. Among patients ≥ 65 years old, genotype 2 patients and genotype 1 patients with a low baseline viral load or achieving RVR or male may benefit from combination therapy.