Shizan Xu

In vitro and in vivo study of epigallocatechin-3-gallate-induced apoptosis in aerobic glycolytic hepatocellular carcinoma cells involving inhibition of phosphofructokinase activity

Glycolysis, as an altered cancer cell-intrinsic metabolism, is an essential hallmark of cancer. Phosphofructokinase (PFK) is a metabolic sensor in the glycolytic pathway, and restricting the substrate availability for this enzyme has been researched extensively as a target for chemotherapy. In the present study, we investigated that the effects of epigallocatechin-3-gallate (EGCG), an active component of green tea, on inhibiting cell growth and inducing apoptosis by promoting a metabolic shift away from glycolysis in aerobic glycolytic hepatocellular carcinoma (HCC) cells. EGCG modulated the oligomeric structure of PFK, potentially leading to metabolic stress associated apoptosis and suggesting that EGCG acts by directly suppressing PFK activity. A PFK activity inhibitor enhanced the effect, while the allosteric activator reversed EGCG-induced HCC cell death. PFK siRNA knockdown-induced apoptosis was not reversed by the activator. EGCG enhanced the effect of sorafenib on cell growth inhibition in both aerobic glycolytic HCC cells and in a xenograft mouse model. The present study suggests a potential role for EGCG as an adjuvant in cancer therapy, which merits further investigation at the clinical level.

Shikonin Attenuates Concanavalin A-Induced Acute Liver Injury in Mice via Inhibition of the JNK Pathway

Objective. Shikonin possesses anti-inflammatory effects. However, its function in concanavalin A-induced acute liver injury remains uncertain. The aim of the present study was to investigate the functions of shikonin and its mechanism of protection on ConA-induced acute liver injury. Materials and Methods. Balb/C mice were exposed to ConA (20 mg/kg) via tail vein injection to establish acute liver injury; shikonin (7.5 mg/kg and 12.5 mg/kg) was intraperitoneally administered 2 h before the ConA injection. The serum liver enzyme levels and the inflammatory cytokine levels were determined at 3, 6, and 24 h after ConA injection. Results. After the injection of ConA, inflammatory cytokines IL-1β, TNF-α, and IFN-γ were significantly increased. Shikonin significantly ameliorated liver injury and histopathological changes and suppressed the release of inflammatory cytokines. The expressions of Bcl-2 and Bax were markedly affected by shikonin pretreatment. LC3, Beclin-1, and p-JNK expression levels were decreased in the shikonin-pretreated groups compared with the ConA-treated groups. Shikonin attenuated ConA-induced liver injury by reducing apoptosis and autophagy through the inhibition of the JNK pathway. Conclusion. Our results indicated that shikonin pretreatment attenuates ConA-induced acute liver injury by inhibiting apoptosis and autophagy through the suppression of the JNK pathway.

The protective effects of shikonin on hepatic ischemia/reperfusion injury are mediated by the activation of the PI3K/Akt pathway

Hepatic ischemia/reperfusion (I/R) injury, which can result in severe liver injury and dysfunction, occurs in a variety of conditions such as liver transplantation, shock, and trauma. Cell death in hepatic I/R injury has been linked to apoptosis and autophagy. Shikonin plays a significant protective role in ischemia/reperfusion injury. The purpose of the present study was to investigate the protective effect of shikonin on hepatic I/R injury and explore the underlying mechanism. Mice were subjected to segmental (70%) hepatic warm ischemia to induce hepatic I/R injury. Two doses of shikonin (7.5 and 12.5 mg/kg) were administered 2 h before surgery. Balb/c mice were randomly divided into four groups: normal control, I/R, and shikonin preconditioning at two doses (7.5 and 12.5 mg/kg). The serum and liver tissues were collected at three time points (3, 6, and 24 h). Shikonin significantly reduced serum AST and ALT levels and improved pathological features. Shikonin affected the expression of Bcl-2, Bax, caspase 3, caspase 9, Beclin-1, and LC3, and upregulated PI3K and p-Akt compared with the levels in the I/R group. Shikonin attenuated hepatic I/R injury by inhibiting apoptosis and autophagy through a mechanism involving the activation of PI3K/Akt signaling.

15d-PGJ2 alleviates ConA-induced acute liver injury in mice by up-regulating HO-1 and reducing hepatic cell autophagy

OBJECTIVE In this study, we confirmed a protective effect of 15d-PGJ2 in concanavalin A (ConA)-induced fulminant hepatitis in mice and investigated the potential mechanism. MATERIALS AND METHODS Balb/C mice were injected with ConA (25mg/kg) to induce acute fulminant hepatitis, and 15d-PGJ2 (2.5-10μg) was administered 30min after the ConA injection. The histological grade, pro-inflammatory cytokine and ROS levels, apoptosis and autophagy activity, the expression of HO-1, Nrf2, JNK and Bcl-2 activity were determined 2, 4, and 8h after the ConA injection. RESULTS Following ConA challenge, the expression of cytokines tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) was up-regulated. Treatment with 15d-PGJ2 reduced the pathological effects of ConA-induced fulminant hepatitis and significantly reduced the levels of TNF-α, IL-1β and ROS after injection. 15d-PGJ2 inhibited apoptosis and autophagic cell death, facilitated Nrf2 nuclear translocation, increased HO-1 expression and suppressed the JNK activation. CONCLUSION 15d-PGJ2 alleviates ConA-induced acute liver injury in mice by up-regulating the anti-oxidative stress factor HO-1 and reducing the production of cytokines and ROS, thereby inhibiting hepatic cell autophagy probably induced by ROS.

Pretreatment with propylene glycol alginate sodium sulfate ameliorated concanavalin A-induced liver injury by regulating the PI3K/Akt pathway in mice

Aims: Propylene glycol alginate sodium sulfate (PSS), a sulfated polysaccharide possesses anti‐inflammatory effects. Here, we investigated the effect of PSS on concanavalin A (Con A)‐induced liver injury in mice and examined the underlying mechanisms. Main methods: Balb/C mice were injected intravenously with Con A (25 mg/kg) to generate a model of acute liver injury. PSS (25 or 50 mg/kg) was injected intraperitoneally 1 h before the Con A administration. The levels of serum liver enzymes, inflammatory cytokines, and other marker proteins were determined, and liver injury was assessed histopathologically 2, 8, and 24 h after Con A injection. Key findings: Pretreatment with PSS reduced the levels of serum liver enzymes, inflammatory cytokines such as tumor necrosis factor (TNF)‐&agr; and interleukin (IL)‐1&bgr;, and attenuated histopathological damage in Con A‐induced liver injury in mice. The effects of Con A were mediated by apoptosis and autophagy, as indicated by changes in protein and gene expression of related factors after Con A injection. PSS activated the phosphatidylinositol 3‐kinase (PI3K)/protein kinase B (Akt) pathway and showed a protective function against apoptosis and autophagy. Significance: PSS ameliorated Con A‐induced liver injury by downregulating inflammatory cytokines including TNF‐&agr; and IL‐1&bgr; and regulating apoptosis and autophagy via the PI3K/Akt pathway.

The liver protection of propylene glycol alginate sodium sulfate preconditioning against ischemia reperfusion injury: focusing MAPK pathway activity

Hepatic ischemia reperfusion (IR) injury contributes to the morbidity and mortality associated with liver surgery. This study investigated the protective function and mechanism of propylene glycol alginate sodium sulfate (PSS), a sulfated polysaccharide, in a mouse hepatic IR injury model. PSS (25 or 50 mg/kg) or saline were injected intraperitoneally to male Balb/c mice 1 h before 45 min of 70% warm hepatic ischemia and 2, 8, and 24 h of reperfusion. Serum and liver tissue samples were collected for evaluation of hepatocellular damage, liver histology, and assay of inflammatory cytokines, apoptosis- and autophagy-related proteins, and proteins in the mitogen-activated protein kinase (MAPKs). Histological injury and release of transaminases, and inflammatory cytokine production were significantly reduced by PSS pretreatment. The expression of apoptosis- and autophagy-related proteins, and the activation of MAPK signal, including jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and P38 were all affected by PSS treatment compared with IR model controls. PSS protected the liver from IR injury by suppressing the MAPK signaling and down-regulating inflammation, apoptosis, and autophagy.

Quercetin Pretreatment Attenuates Hepatic Ischemia Reperfusion-Induced Apoptosis and Autophagy by Inhibiting ERK/NF-κB Pathway

Background Hepatic ischemia reperfusion (IR) injury is a common phenomenon in transplantation or trauma. The aim of the present study was to determine the protective effect of quercetin (QE) on hepatic IR injury via the ERK/NF-κB pathway. Methods Mice were randomized into the sham, IR, QE100 + IR, and QE200 + IR groups. Quercetin was administered intragastrically daily at two doses (100 mg/kg and 200 mg/kg) for 5 days prior to IR injury. The expression levels of liver enzymes, inflammatory cytokines, and other marker proteins were determined at 2, 8, and 24 hours after IR. And they were compared among these groups. Results Compared with the IR group, the treatment of QE reduced the release of cytokines, leading to inhibition of apoptosis and autophagy via downregulation of the ERK/NF-κB pathway in this model of hepatic IR injury. Conclusion Apoptosis and autophagy caused by hepatic IR injury were inhibited by QE following a reduction in the release of inflammatory cytokines, and the relationship between the two may be associated with inactivation of the ERK/NF-κB pathway.

Cerebral Hemodynamics and Cognitive Function in Cirrhotic Patients with Hepatic Encephalopathy

Aims. To investigate cerebral hemodynamics in cirrhotic patients with HE and to observe effects of treatment in cerebral hemodynamics and correlations among ammonia, cerebral hemodynamics, and cognitive function. Methods. There were four groups: healthy controls (group 1), cirrhosis without HE (group 2), cirrhosis with MHE (group 3), and cirrhosis with OHE (group 4). Ammonia and cerebral hemodynamics (by TCD) were assessed. Patients in group 3 were subsequently randomized to two subgroups: the control (group A) and the treated (group B, treated with lactulose for two months), and they were retested for ammonia and TCD after treatment. Results. Ammonia, Vm, Vd, PI, and RI were statistically different before treatment, and ammonia, PI, and RI levels paralleled the severity of HE (P < 0.05). In group B, Vd increased and ammonia, PI, and RI declined following treatment (P < 0.05), while there were no differences in group A (P > 0.05). Correlations were found between ammonia and Vd, PI, RI, NCT-A, and DST and also found between Vd, PI, RI, and NCT-A and DST (P < 0.05). Conclusions. This study revealed that cerebral hemodynamics were related to the severity of HE and cerebral autoregulation was impaired. There were tight correlations among ammonia, cerebral hemodynamics, and cognitive function, and, following treatment, cerebral hemodynamics improved.

Metformin and Diammonium Glycyrrhizinate Enteric-Coated Capsule versus Metformin Alone versus Diammonium Glycyrrhizinate Enteric-Coated Capsule Alone in Patients with Nonalcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus.

Objective. The present study was conducted to compare the efficacy of metformin combined with diammonium glycyrrhizinate enteric-coated capsule (DGEC) versus metformin alone versus DGEC alone for the treatment of nonalcoholic fatty liver disease (NAFLD) in patients with type 2 diabetes mellitus (T2DM). Subjects and Methods. 163 patients with NAFLD and T2DM were enrolled in this 24-week study and were randomized to one of three groups: group 1 was treated with metformin alone; group 2 was treated with DGEC alone; group 3 received metformin plus DGEC combination therapy. Anthropometric parameters, liver function, lipid profile, serum ferritin (SF), metabolic parameters, liver/spleen computed tomography (CT) ratio, and fibroscan value were evaluated at baseline and after 8, 16, and 24 weeks of treatment. Results. After 24 weeks, significant improvements in all measured parameters were observed in three groups (P < 0.05) except for the improvements in low density lipoprotein cholesterol (LDL-C) and metabolic parameters in group 2 which did not reach statistical significance (P > 0.05). Compared with group 1 and group 2, the patients in group 3 had greater reductions in observed parameters apart from CB and TB (P < 0.05). Conclusions. This study showed that metformin plus DGEC was more effective than metformin alone or DGEC alone in reducing liver enzymes, lipid levels, and metabolic parameters and ameliorating the degree of hepatic fibrosis in patients with NAFLD and T2DM.

Portulaca Extract Attenuates Development of Dextran Sulfate Sodium Induced Colitis in Mice through Activation of PPARγ

Portulaca oleracea L. is a traditional Chinese medicine, which has been used as adjuvant therapy for inflammatory bowel disease (IBD). However, the mechanism of its activity in IBD still remains unclear. Since previous studies have documented the anti-inflammatory effect of peroxisome proliferator activated receptors-γ (PPAR-γ), Portulaca regulation of PPAR-γ in inflammation was examined in current study. Ulcerative colitis (UC) was generated by 5% dextran sulfate sodium (DSS) in mice and four groups were established as normal control, DSS alone, DSS plus mesalamine, and DSS plus Portulaca. Severity of UC was evaluated by body weight, stool blood form, and length of colorectum. Inflammation was examined by determination of inflammatory cytokines (TNF-a, IL-6, and IL-1a). Portulaca extract was able to attenuate development of UC in DSS model similar to the treatment of mesalazine. Moreover, Portulaca extract inhibited proinflammatory cytokines release and reduced the level of DSS-induced NF-κB phosphorylation. Furthermore, Portulaca extract restored PPAR-γ level, which was reduced by DSS. In addition, Portulaca extract protected DSS induced apoptosis in mice. In conclusion, Portulaca extract can alleviate colitis in mice through regulation of inflammatory reaction, apoptosis, and PPAR-γ level; therefore, Portulaca extract can be a potential candidate for the treatment of IBD.