Ginseng-derived panaxadiol ameliorates STZ-induced type 1 diabetes through inhibiting RORγ/IL-17A axis.

Retinoic-acid-receptor-related orphan receptor γ (RORγ) is a major transcription factor for proinflammatory IL-17A production. Here, we revealed that the RORγ deficiency protects mice from STZ-induced Type 1 diabetes (T1D) through inhibiting IL-17A production, leading to improved pancreatic islet ß cell function, thereby uncovering a potential novel therapeutic target for treating T1D. We further identified a novel RORγ inverse agonist, ginseng-derived panaxadiol, which selectively inhibits RORγ transcriptional activity with a distinct cofactor recruitment profile from known RORγ ligands. Structural and functional studies of receptor-ligand interactions reveal the molecular basis for a unique binding mode for panaxadiol in the RORγ ligand-binding pocket. Despite its inverse agonist activity, panaxadiol induced the C-terminal AF-2 helix of RORγ to adopt a canonical active conformation. Interestingly, panaxadiol ameliorates mice from STZ-induced T1D through inhibiting IL-17A production in a RORγ-dependent manner. This study demonstrates a novel regulatory function of RORγ with linkage of the IL-17A pathway in pancreatic ß cells, and provides a valuable molecule for further investigating RORγ functions in treating T1D.

Synthesis of platelet-activating factor and its receptor expression in Kupffer cells in rat carbon tetrachloride-induced cirrhosis.

AIM: To determine the platelet-activating factor (PAF) synthesis and its receptor expression in Kupffer cells in rat carbon tetrachloride-induced cirrhosis. METHODS: Kupffer cells, isolated from the livers of control and CCl4-induced cirrhotic rats, were placed in serum-free medium overnight. PAF saturation binding, ET-1 saturation and competition binding were assayed. ET-1 induced PAF synthesis, mRNA expression of PAF, preproendothelin-1, endothelin A (ETA) and endothelin B (ETB) receptors were also determined. RESULTS: A two-fold increase of PAF synthesis (1.42 +/- 0.14 vs 0.66 +/- 0.04 pg/microg DNA) and a 1.48-fold increase of membrane-bound PAF (1.02 +/- 0.06 vs 0.69 +/- 0.07 pg/microg DNA) were observed in activated Kupffer cells of cirrhotic rats. The application of ET-1 to Kupffer cells induced PAF synthesis in a concentration-dependent manner in both cirrhotic and normal rats via ETB receptor, but PAF synthesis in the activated Kupffer cells was more effective than that in the normal Kupffer cells. In activated Kupffer cells, PAF receptor expression and PAF binding capacity were markedly enhanced. Activated Kupffer cells raised the [125 I]-ET-1 binding capacity, but changed neither the affinity of the receptors, nor the expression of ETA receptor. CONCLUSION: Kupffer cells in the course of CCl4-induced cirrhosis are the main source of increased PAF. ET-1 is involved endogenously in stimulating the PAF synthesis in activated Kupffer cells via ETB receptor by paracrine. ETA receptor did not appear in activated Kupffer cells, which may exacerbate the hepatic and extrahepatic complications of cirrhosis.

Hepatic stellate cells may be potential effectors of platelet activating factor induced portal hypertension.

AIM: To determine platelet activating factor (PAF) receptor expression in cirrhotic hepatic stellate cells. METHODS: Hepatic stellate cells, isolated from the livers of control and CCl(4)-induced cirrhotic rats, were placed in serum-free medium after overnight culture. We determined the PAF receptor in hepatic stellate cells by saturation binding technique and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR), and the effects of PAF and its antagonist BN52021 on prostaglandin E(2) (PGE(2)) release by stellate cells. RESULTS: Scatchard analysis indicated the presence of PAF receptor with dissociation constant (Kd) of 4.66 nmol/L and maximum binding capacity (Bmax) of 24.65 fmol/microg in cirrhotic stellate cells. Compared with the control, the maximum PAF binding capacity increased significantly (Bmax: 24.65 +/- 1.96 fmol/microg. DNA, R = 0.982 vs 5.74 +/- 1.55 fmol/microg. DNA, R = 0.93; P < 0.01), whereas receptor affinity had no significant difference (Kd of 4.66 +/- 0.33 nmol/L for the cirrhosis and 3.51 +/- 0.26 nmol/L for the control; P > 0.05). Consistent with the receptor binding data, the mRNA expression of PAF receptor was increased significantly in cirrhotic stellate cells. PAF in a concentration-dependent manner induced PGE(2) synthesis in cirrhotic hepatic stellate cells, but the effects were blocked significantly by BN52021. CONCLUSION: Cirrhosis sensitizes hepatic stellate cells to PAF by elevating its receptor level and hepatic stellate cells maybe potential effectors of PAF induced portal hypertension.

Augmenter of liver regeneration promotes hepatocyte proliferation induced by Kupffer cells.

AIM: To observe the effects of augmenter of liver regeneration (ALR) on Kupffer cells and to determine whether ALR promotes hepatocyte proliferation induced by Kupffer cells. METHODS: Kupffer cells and hepatocytes were cultured in vitro and various concentrations of recombinant rat ALR (rrALR) were added. 3H-thymidine, BrdU and 3H-leucine incorporation was determined in cultured Kupffer cells and hepatocytes, in hepatocytes conditioned by Kupffer cells, and in associated medium. rrALR was labeled by iodination and used to determine its binding activity by Scatchard analysis in Kupffer cells and primarily cultured rat hepatocytes. RESULTS: rrALR stimulated DNA replication in Kupffer cells and protein synthesis both in cells and in medium in a non-concentration-dependent manner. The effect was significant at the concentration of 1 microg/L ALR. However, rrALR had no effect on primarily cultured hepatocytes, when hepatocytes were cultured with the Kupffer cell medium conditioned by ALR, DNA replication and protein synthesis in hepatocytes increased significantly at the concentration of 1 microg/L ALR. When the ALR concentration was increased, its effect on hepatocyte proliferation decreased to the basal level. Scatchard analysis indicated the presence of a single class of high affinity receptors with a dissociation constant (Kd) of 0.883 nmol/L and a maximum binding capacity (Bmax) of 126.1 pmol/g protein in the rat Kupffer cells. CONCLUSION: ALR can promote hepatocyte proliferation induced by Kupffer cells, which is associated with the concentration of ALR, suggesting that Kupffer cells play a dual role in liver regeneration.

Effect of increased hepatic platelet activating factor and its receptor portal hypertension in CCl4-induced liver cirrhosis.

AIM: To evaluate the changes in hepatic platelet activating factor (PAF) and its receptors and their effect on portal pressure of cirrhotic rats induced by CCl4. METHODS: A model of liver cirrhosis was replicated in rats by intra-peritoneal injection of CCl4 for 8 wk. We determined the effect of hepatic PAF and its receptor level on portal and arterial pressure by EIA, saturation binding and RT-PCR technique. RESULTS: Compared to control rats, cirrhotic rats had higher hepatic PAF levels and output as well as higher plasma PAF levels (P<0.01, P<0.01, P<0.05, respectively). Both hepatic PAF receptor mRNA levels and PAF binding were nearly 3-fold greater in cirrhotic rats (P<0.01). Portal injection of PAF (1 g/kg WT) increased the portal pressure by 22% and 33% in control and cirrhotic rats, respectively. In contrast, the arterial pressure was decreased in the both groups (54% in control rats and 42% in cirrhotic rats). Injection of the PAF antagonist BN52021 (5 mg/kg WT) decreased the portal pressure by 16% in cirrhotic rats but had no effect in the control rats. CONCLUSION: The upregulation of the PAF system contributes to hepatic hemodynamic and metabolic abnormalities in cirrhosis, and the increased release of PAF into the circulation has impacts on the systemic hemodynamics.

[Influence of platelet activating factor and its antagonist on portal hypertension associated with liver cirrhosis: an experiment with rats].

OBJECTIVE: To investigate the influence of platelet activating factor (PAF) and its antagonist BN52021 on portal hypertension associated with liver cirrhosis. METHODS: Ten SD rats were injected intraperitoneally with carbon tetrachloride to establish a liver cirrhosis model and 10 rats were injected with olive oil as controls. The concentrations of PAF in the blood and liver was examined by rapid (3)H-PAF scintillation proximity assay and the hepatic PAF binding capacity was examined by receptor saturation binding technique. The pressure of portal vein and pressure of femoral artery were measured by intubation method. BN52021 was infused into the portal vein to observe its influence on the blood pressure. RESULTS: The hepatic PAF levels of the cirrhotic rats was 4.0 ng/g +/- 0.4 ng/g, significantly higher than that of the control rats (2.7 ng/g +/- 0.5 ng/g, P < 0.01). The hepatic efflux PAF level of the cirrhotic rats was 6.3 ng/g +/- 0.6 ng/g, significantly higher than that of the control rats (3.4 ng/g +/- 0.6 ng/g, P < 0.01). The hepatic output PAF levels of the cirrhotic rats was 1.0 ng/g +/- 0.6 ng/g, significantly lower than that of the control rats (0.3 ng/g +/- 0.5 ng/g, P < 0.01). The maximum PAF binding capacity of the cirrhotic rats was 2.8 +/- 0.21 fmol/microg protein, significantly higher than that of the control rats (0.9 +/- 0.06 fmol/microg protein, P < 0.01). However, the receptor affinity was not significantly different between these 2 groups. The portal pressure of the cirrhotic rats was 12.2 mm Hg +/- 0.7 mm Hg, significantly higher than that of the control rats (5.3 mm Hg +/- 0.6 mm Hg, P < 0.01). The femoral arterial pressure of the cirrhotic rats was 82 mm Hg +/- 10 mm Hg, significantly lower than that of the control rats (114 mm Hg +/- 9 mm Hg, P < 0.01). Infusion of PAF via the portal vein increased the portal pressure from 12.1 mm Hg +/- 0.6 mm Hg with an increase of 32% (P < 0.01) in the cirrhotic rats, and from 7.7 mm Hg +/- 0.8 mm Hg with an increase of 23%. The PAF response of the cirrhotic rats was 4.1 mm Hg +/- 1.0 mm Hg (227%), significantly higher than that of the control rats (1.8 mm Hg +/- 0.3 mm Hg, P < 0.01). The femoral artery pressure decreased from 82 mm Hg +/- 10 mm Hg to 48 mm Hg +/- 4 mm Hg (P < 0.01) in the cirrhotic rats, and from 114 mm Hg +/- 9 mm Hg to 52 mm Hg +/- 4 mm Hg (P < 0.01). After portal infusion of BN52021 the portal pressure decreased from 14.6 mm Hg +/- 1.6 mm Hg to 12.3 mm Hg +/- 0.8 mm Hg (P < 0.05) with a decrease of 16%, however, did not significantly influenced the femoral arterial pressure in the cirrhotic rats, and did not significantly influenced the portal pressure and femoral arterial pressure in the control rats. CONCLUSION: The increased hepatic PAF synthesis in cirrhotic is the major source of elevated circulating PAF It upregulates the hepatic hemodynamics that contributes to portal hypertension. The increased portal pressure by endogenous PAF can be decreased to a certain extent by BN52021 which may be used in treatment of portal hypertension.

Autologous cytokine-induced killer cell therapy in clinical trial phase I is safe in patients with primary hepatocellular carcinoma.

AIM: To investigate the influence of autologous cytokine-induced killer (CIK) cells on the phenotypes of CIK effector cells, peripheral T lymphocyte subsets and dendritic cell subsets in patients with primary hepatocellular carcinoma (HCC). METHODS: Peripheral blood mononuclear cells (PBMC) were collected by a blood cell separator from 13 patients with HCC, then expanded by priming them with interferon-gamma (IFN-gamma) followed by monoclonal antibody (mAb) against CD3 and interleukin-2 (IL-2) the next day. The phenotypic patterns of CIK cells were characterized by flow cytometry on d 0, 4, 7, 10, 13 and 15 of incubation, respectively. Then, 5 mL of venous blood was obtained from HCC patients before or 8-10 d after CIK cells were transfused into patients to assess the influence of CIK cells on the percentages of effector cells, and proportions of DC1 or DC2 in peripheral blood by flow cytometry. RESULTS: After two weeks of in vitro incubation, the percentages of CD3(+)CD8(+), CD3(+)CD56(+), and CD25(+) cells increased significantly from 33.5+/-10.1%, 7.7+/-2.8%, and 12.3+/-4.5% to 36.6+/-9.0% (P<0.05), 18.9+/-6.9% (P<0.01), and 16.4+/-5.9% (P<0.05), respectively. However, the percentages of CD3(+)CD4(+) and NK cells had no significant difference. The percentages of CD3(+) and CD3(+)CD8(+) cells were kept at high levels during the whole incubation period, but those of CD25(+), and CD3(+)CD56(+) cells began to decrease on d 7 and 13, respectively. The proportions of type I dendritic cell (DC1) and type II dendritic cell (DC2) subsets increased from 0.59+/-0.23% and 0.26+/-0.12% before CIK cell therapy to 0.85+/-0.27% and 0.43+/-0.19% (all P<0.01) after CIK cell transfusion, respectively. The symptoms and characteristics of HCC patients were relieved without major side effects. CONCLUSION: Our results indicated that autologous CIK cells can efficiently improve the immunological status in HCC patients, and may provide a potent approach for HCC patients as the adoptive immunotherapy.

[Identification of immunological effector cells after autologous cytokine-induced killer cells treatment and its clinical implication in hepatocellular carcinoma patients].

OBJECTIVE: To investigate the alteration of the cellular profiles of T lymphocyte subsets and dendritic cell subsets in peripheral blood of primary hepatocellular carcinoma (HCC) patients after being transfused with autologous cytokine-induced killer cells (CIK) in patients, then to evaluate the clinical efficacy of the immune therapeutic strategy. METHODS: Peripheral blood mononuclear cells (PBMCs) from 13 patients with primary were collected using blood cell separator, and expanded in the fresh AIM-V medium in the presence of cytokine cocktail including interferon-gamma (IFN-gamma), monoclonal antibody (mAb) against CD3 and interleukin-2 (IL-2). The phenotypic patterns of CIK cells were longitudinally characterized by flow cytometry on day 0, 4, 7, 10,13 and 15 during the incubation period. PBMCs obtained from HCC patients before or after CIK cells transfusion into bodies to assay the changes of proportion of DC1 or DC2 in peripheral blood. RESULTS: After in vitro incubation for 14 or 15 days, a large of CD3(+)CD56(+) cells were produced from their progenitors and the percentages of CD3(+)CD8(+), CD3(+)CD56(+), CD25(+) cells significantly increased from 33.5% +/- 10.1%, 7.7% +/- 2.8%, and 12.3% +/- 4.5% at the beginning to 36.6% +/- 9.0% (P < 0.05), 18.9% +/- 6.9% (P < 0.01), and 16.4% +/- 5.9% (P < 0.05) at the day 15, respectively. In contrast, the percentages of CD3(+)CD4(+) and NK cells displayed no significant difference. The percentages of CD3(+), CD3(+)CD8(+) cells was held at a higher level during the whole incubation period, however those of the CD25(+), and CD3(+)CD56(+) cells began decreasing on day 7 and day 13, respectively. The proportion of type I of dendritic cells (DC1) and type II of dendritic cells (DC2) subsets increased from 0.59% +/- 0.23% and 0.26% +/- 0.12% before CIK cell transfusion to 0.85% +/- 0.27% and 0.43% +/- 0.20% (all P < 0.01) after CIK cell transfusion. The symptom of HCC patients receiving the CIK cell therapy was markedly ameliorated, and not side effect was seen in the treatment. CONCLUSION: Our results indicated that autologous CIK cells is able to boost the cellular immunological function in HCC patients, which probably provide a potent immune therapeutic strategy for HCC patients.

Efficacy of argon-helium cryosurgical ablation on primary hepatocellular carcinoma: a pilot clinical study.

BACKGROUND AND OBJECTIVE: Recent years, great progression has been made in treating primary hepatocellular carcinoma (HCC) with argon-helium cryosurgical ablation. This study was to evaluate its efficacy on unresectable primary HCC. METHODS: A total of 124 primary HCC patients were divided into early stage, middle stage and advanced stage groups according to BCLC staging classification. Clinical symptoms, tumor size, serum level of alpha-fetoprotein (AFP), complications, and survival time were analyzed. RESULTS: After cryoablation of the tumors, serum level of AFP was reduced in 76 (82.6%) patients, 205 (92.3%) of the 222 tumor lesions were diminished or unchanged. Untill April 2008, 14 patients survived and 110 died. The median survival time was 31.25 months in early stage group, 17.41 months in middle stage group and 6.82 months in advanced stage group. CONCLUSION: For the patients with unresectable HCC, argon-helium cryosurgical ablation has the advantages of few complications and certain efficacy.