Calcium signaling of pancreatic acinar cells in the pathogenesis of pancreatitis

Pancreatitis is an increasingly common and sometimes severe disease that lacks a specific therapy. The pathogenesis of pancreatitis is still not well understood. Calcium (Ca2+) is a versatile carrier of signals regulating many aspects of cellular activity and plays a central role in controlling digestive enzyme secretion in pancreatic acinar cells. Ca2+ overload is a key early event and is crucial in the pathogenesis of many diseases. In pancreatic acinar cells, pathological Ca2+ signaling (stimulated by bile, alcohol metabolites and other causes) is a key contributor to the initiation of cell injury due to prolonged and global Ca2+ elevation that results in trypsin activation, vacuolization and necrosis, all of which are crucial in the development of pancreatitis. Increased release of Ca2+ from stores in the intracellular endoplasmic reticulum and/or increased Ca2+ entry through the plasma membrane are causes of such cell damage. Failed mitochondrial adenosine triphosphate (ATP) production reduces re-uptake and extrusion of Ca2+ by the sarco/endoplasmic reticulum Ca2+-activated ATPase and plasma membrane Ca2+-ATPase pumps, which contribute to Ca2+ overload. Current findings have provided further insight into the roles and mechanisms of abnormal pancreatic acinar Ca2+ signals in pancreatitis. The lack of available specific treatments is therefore an objective of ongoing research. Research is currently underway to establish the mechanisms and interactions of Ca2+ signals in the pathogenesis of pancreatitis.

Interference of suppressor of cytokine signaling 3 promotes epithelial-mesenchymal transition in MHCC97H cells

AIM:To investigate the role of suppressor of cytokine signaling 3 (SOCS3) silencing in epithelial-mesenchymal transition (EMT) involved in a human hepatocellular carcinoma MHCC97H cell line.METHODS:MHCC97H cells were transiently transfected with SOCS3 small-interfering RNA (siRNA).Morphological changes of the transfected cells were observed under microscope.Expressions of E-cadherin,Vimentinand α-smooth muscle actin (α-SMA) were identified with immunofluorescence.Furthermore,protein expressions and mRNA levels of characteristic markers of EMT (E-cadherin,Vimentin,α-SMA and Snail) were detected by Western blotting,quantitative real-time polymerase chain reaction.Transforming growth factor-β1 (TGF-β1) levels in the supernatant were measured with enzyme-linked immunosorbent assay.RESULTS:The transfected cells with SOCS3 siRNA showed a morphological alteration from a typical cobblestone morphology to mesenchymal spindle-shaped and fusiform features.SOCS3 siRNA lessened immunofluorescent expression of E-cadherin,but elicited immunofluorescent expressions of Vimentin and α-SMA in MHCC97H cells.More importantly,compared with the negative control,depletion of SOCS3 resulted in the decrease of the epithelial marker E-cadherin (P < 0.05),and the increase of the mesenchymal markers Vimentin and α-SMA and the transcription factor Snail in MHCC97H cells (P < 0.05).Moreover,compared with the negative control,SOCS3 siRNA evidently enhanced TGF-β1 secretion in MHCC97H cells (200.20 ± 29.02 pg/mL vs 490.20 ± 92.43 pg/mL,P < 0.05).CONCLUSION:SOCS3 silencing is able to promote EMT in MHCC97H cells via changing the phenotypic characteristics and modulating the characteristic markers.

Inhibitory effects of saikosaponin-d on CCl_4-induced hepatic fibrogenesis in rats

AIM： To investigate the suppressive effect of saikosaponin-d （SSd） on hepatic fibrosis in rats induced by CCh injections in combination with alcohol and high fat, low protein feeding and its relationship with the expression of nuclear factor-κB （NF-κB）, tumor necrosis factor-alpha （TNF-α） and interleukins-6 （IL-6）. METHODS： Hepatic fibrosis models were induced by subcutaneous injection of CCh at a dosage of 3 mL/kg in rats. At the same time, rats in treatment groups were injected intraperitoneally with SSd at different doses （1.0, 1.5 and 2.0 mg/kg） once daily for 6 wk in combination with CCh, while the control group received olive oil instead of CCh. At the end of the experiment, rats were anesthetized and killed （except for 8 rats which died during the experiment; 2 from the model group, 3 in high-dose group, 1 in medium-dose group and 2 in lowdose group）. Hernatoxylin and eosin （HE） staining and Van Gieson staining were used to examine the changes in liver pathology. The levels of alanine aminotransferase （ALT）, triglyeride （TG）, albumin （ALB）, globulin （GLB）, hyaluronic acid （HA） and larninin （LN） in serum and the content of hydroxyproline （HYP） in liver were measured by biochemical examinations and radioimmuneoassay, respectively. In addition, the expression of TNF-α and IL-6 in liver homogenate was evaluated by enzymelinked immunosorbent assay （ELISA） and the levels of NF-κBp65 and I-κBa in liver tissue were analyzed by Western blotting. RESULTS： Both histological examination and Van Gieson staining demonstrated that SSd could attenuate the area and extent of necrosis and reduce the scores of liver fibrosis. Similarly, the levels of ALT, TG, GLB, HA, and LN in serum, and the contents of HYP, TNF-α and IL-6 in liver were all significantly increased in model group in comparison with those in control group. Whereas, the treatment with SScl markedly reduced all the above parameters compared with the model group, especially in the medium group （ALT： 412 ± 94.5 IU/L vs 113.76 ± 14.91 IU/L, TG： 0.95 ± 0.16 mmol/L vs 0.51 ± 0.06 mmol/L, GLB： 35.62 ± 3.28 g/L vs 24.82 ± 2.73 g/L, HA： 42.15 ± 8.25 ng/mL vs 19.83 ± 3.12 ng/mL, LN： 27.56 ± 4.21 ng/mL vs 13.78 ± 2.57 ng/mL, HYP： 27.32 ± 4.32 ug/mg vs 16.20 ± 3.12 ug/mg, TNF-a： 4.38 ± 0.76 ng/L vs 1.94 ± 0.27 ng/L, IL-6：28.24 ± 6.37 pg/g vs 12.72 ± 5.26 pg/g, respectively, P 〈 0.01）. SSd also decreased ALB in serum （28.49 ± 4.93 g/L vs 37.51 ± 3.17 g/L, P 〈 0.05）. Moreover, the expression of NF-KB p65 in the liver of treated groups was lower than that in model groups while the expression of I-κBa was higher in treated group than in model group （P 〈 0.01）. The expression of NF-κBp65 and TNF-a had a positive correlation with the level of HA in serum of rats after treatment with CCh （r = 0.862, P 〈 0.01; r = 0.928, P 〈 0.01, respectively）. CONCLUSION： SSd attenuates CCh-induced hepatic fibrosis in rats, which may be related to its effects of hepato-protective and anti-inflammation properties, the down-regulation of liver TNF-a, IL-6 and NF-κBp65 expression and the increased I-κBa activity in liver.

Scutellaria barbate extract induces apoptosis of hepatoma H22 cells via the mitochondrial pathway involving caspase-3

AIM： To study the growth inhibitory and apoptotic effects of Scutellaria barbata D.Don （S. barbata） and to determine the underlying mechanism of its antiturnor activity in mouse liver cancer cell line H22.METHODS： Proliferation of H22 cells was examined by MTT assay. Cellular morphology of PC-2 cells was observed under fluorescence microscope and transmission electron microscope （EM）. Mitochondrial transmembrane potential was determined under laser scanning confocal microscope （LSCM） with rhodamine 123 staining. Flow cytometry was performed to analyze the cell cycle of H22 cells with propidium iodide staining. Protein level of cytochrome C and caspase-3 was measured by semi-quantitive RT-PCR and Western blot analysis. Activity of caspase-3 enzyme was measured by spectrofluorometrv.RESULTS： M-I-I- assay showed that extracts from S. barbata （ESB） could inhibit the proliferation of H22 cells in a time-dependent manner. Among the various phasesof cell cycle, the percentage of cells in S phase was significantly decreased, while the percentage of cells in G1 phase was increased. Flow cytometry assay also showed that ESB had a positive effect on apoptosis. Typical apoptotic morphologies such as condensation and fragmentation of nuclei and blebbing membrane of apoptotic cells could be observed under transmission electron microscope and fluorescence microscope. To further investige the molecular mechanism behind ESB-induced apoptosis, ESB-treated cells rapidly lost their mitochondrial transmembrane potential, released mitochondrial cytochrome C into cytosol, and induced caspase-3 activity in a dose-dependent manner. CONCLUSION： ESB can effectively inhibit the proliferation and induce apoptosis of H22 cells involving loss of mitochondrial transmembrane potential, release of cytochrome C, and activation of caspase-3.

Perspectives of traditional Chinese medicine in pancreas protection for acute pancreatitis

Acute pancreatitis(AP)is one of the most common diseases.AP is associated with significant morbidity and mortality,but it lacks specific and effective therapies.Traditional Chinese medicine(TCM)is one of the most popular complementary and alternative medicine modalities worldwide for the treatment of AP.The current evidence from basic research and clinical studies has shown that TCM has good therapeutic effects on AP.This review summarizes the widely used formulas,single herbs and monomers that are used to treat AP and the potential underlying mechanisms of TCM.Because of the abundance,low cost,and safety of TCM as well as its ability to target various aspects of the pathogenesis,TCM provides potential clinical benefits and a new avenue with tremendous potential for the future treatment of AP.

Exogenous phosphatidylethanolamine induces apoptosis of human hepatoma HepG2 cells via the bcl-2/bax pathway

AIM: To investigate the signaling pathways implicated in phosphatidylethanolamine (PE)-induced apoptosis of human hepatoma HepG2 cells. METHODS: Inhibitory effects of PE on human hepatoma HepG2 cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle, apoptosis and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry. Immunocytochemical assay and Western blotting were used to examine Bcl-2, Bax and caspase-3 protein levels in HepG2 cells treated with PE. RESULTS: PE inhibited the growth of HepG2 cells in a doseand timedependent manner. It did notaffect the cell cycle, but induced apoptosis. PE significantly decreased ΔΨm at 0.25, 0.5 and 1 mmol/L, respectively, suggesting that PE induces cell apoptosis by decreasing the mitochondrial transmembrane potential. The Bcl-2 expression level induced by different concentrations of PE was lower than that in control groups. However, the Bax expression level induced by PE was higher than that in the control group. Meanwhile, PE increased the caspase-3 expression in a doseand time-dependent manner. CONCLUSION: Exogenous PE induces apoptosis of human hepatoma HepG2 cells via the bcl-2/bax pathway.

Changes in count and function of splenic lymphocytes from patients with portal hypertension

AIM: To investigate changes in numbers and proliferative function of splenic lymphocytes in patients with hypersplenism due to portal hypertension (PH), to provide evidence for further study of immune status of the spleen during PH. METHODS: Twelve spleens from patients with hypersplenism due to PH served as the PH group, and four spleens from cases of traumatic spleen rupture were regarded as the control group. After weighing the spleen, lymphocytes were separated and counted using a cell counting plate to calculate the lymphocyte count per gram of spleen tissue (relative quantity) and total lymphocyte count in whole spleen (absolute quantity). The immunohistochemical SP method was used to observe the density and distribution of lymphocytes in the spleen. The MTT method was used to observe changes in lymphocyte proliferative function. RESULTS: As compared to the control group, the splenic lymphocytes in the PH group showed that: (1) There was no difference in distribution but a significant decreasein density; (2) the number of lymphocytes per gram of spleen (relative quantity) decreased significantly (0.822 ± 0.157) × 108 vs (1.174 ± 0.254) × 108, P < 0.01]; (3) with the significant increase in the weight of the PH spleen (832.6 ± 278.2 g vs 211.7 ± 85.6 g, P < 0.01), the total quantity of lymphocytes (absolute quantity) increased significantly (0.685 ± 0.072) × 1011 vs (0.366 ± 0.057) × 1011, P < 0.01]; and (4) the proliferative function of lymphocytes was enhanced: T lymphocytes, (0.022 ± 0.005 vs 0.015 ± 0.003, P < 0.05), and B lymphocytes (0.034 ± 0.006 vs 0.023 ± 0.001, P < 0.01). CONCLUSION: Although lymphocyte density in the spleen decreased in patients with PH, the total quantity of lymphocytes increased because spleen weight increased greatly, along with the proliferating function. With respect to changes in lymphocytes, PH spleens may still have immune function, although it may be disordered. However, complete evaluation of the immune function of the spleen in PH requires more research.

Induction of apoptosis and cell cycle arrest in human HCC MHCC97H cells with Chrysanthemum indicum extract

AIM： To investigate the effects of Chrysanthemum indicum extract （CIE） on inhibition of proliferation and on apoptosis, and the underlying mechanisms, in a human hepatocellular carcinoma （HCC） MHCC97H cell line. METHODS： Viable rat hepatocytes and human endothelial ECV304 cells were examined by trypan blue exclusion and MTT assay, respectively, as normal controls. The proliferation of MHCC97H cells was determined by MTT assay. The cellular morphology of MHCC97H cells was observed by phase contrast microscopy. Flow cytometry was performed to analyze cell apoptosis with annexin V/propidium iodide （PI）, mitochondrial membrane potential with rhodamine 123 and cell cycle with PI in MHCC97H cells. Apoptotic proteins such as cytochrome C, caspase-9, caspase-3 and cell cycle proteins, including P21 and CDK4, were measured by Western blotting. RESULTS： CIE inhibited proliferation of MHCC97H cells in a timeand dose-dependent manner without cytotoxicity in rat hepatocytes and human endothelial ceils. CIE induced apoptosis of MHCC97H cells in a concentration-dependent manner, as determined by flow cytometry. The apoptosis was accompanied by a decrease in mitochondrial membrane potential, release of cytochrome C and activation of caspase-9 and caspase-3. CIE arrested the cell cycle in the S phase by increasing P21 and decreasing CDK4 protein expression. CONCLUSION： CIE exerted a significant apoptotic effect through a mitochondrial pathway and arrested the cell cycle by regulation of cell cycle-related proteins in MHCC97H cells without an effect on normal cells. The cancer-specific selectivity shown in this study suggests that the plant extract could be a promising novel treatment for human cancer.

Emodin and baicalein inhibit sodium taurocholate-induced vacuole formation in pancreatic acinar cells

AIM To investigate the effects of combined use of emodin and baicalein(CEB) at the cellular and organism levelsin severe acute pancreatitis(SAP) and explore the underlying mechanism.METHODS SAP was induced by retrograde infusion of 5% sodium taurocholate into the pancreatic duct in 48 male SD rats. Pancreatic histopathology score, serum amylase activity, and levels of tumour necrosis factor alpha(TNf-α), interleukin 6(IL-6), and IL-10 were determined to assess the effects of CEB at 12 h after the surgery. The rat pancreatic acinar cells were isolated from healthy male SD rats using collagenase. The cell viability, cell ultrastructure, intracellular free Ca2+ concentration, and inositol(1,4,5)-trisphosphate receptor(IP3 R) expression were investigated to assess the mechanism of CEB.RESULTS Pancreatic histopathology score(2.07 ± 1.20 vs 6.84 ± 1.13, P < 0.05) and serum amylase activity(2866.2 ± 617.7 vs 5241.3 ± 1410.0, P < 0.05) were significantly decreased in the CEB(three doses) treatment group compared with the SAP group(2.07 ± 1.20 vs 6.84 ± 1.13, P < 0.05). CEB dose-dependently reduced the levels of the pro-inflammatory cytokines IL-6(466.82 ± 48.55 vs 603.50 ± 75.53, P < 0.05) and TNF-α(108.04 ± 16.10 vs 215.56 ± 74.67, P < 0.05) and increased the level of the anti-inflammatory cytokine IL-10(200.96 ± 50.76 vs 54.18 ± 6.07, P < 0.05) compared with those in the SAP group. CEB increased cell viability, inhibited cytosolic Ca2+ concentration, and significantly ameliorated intracellular vacuoles and IP3 m RNA expression compared with those in the SAP group(P < 0.05). There was a trend towards decreased IP3 R protein in the CEB treatment group; however, it did not reach statistical significance(P > 0.05).CONCLUSION These results at the cellular and organism levels reflect a preliminary mechanism of CEB in SAP and indicate that CEB is a suitable approach for SAP treatment.

Wall shear stress in portal vein of cirrhotic patients with portal hypertension

AIM To investigate wall shear stress(WSS) magnitude and distribution in cirrhotic patients with portal hypertension using computational fluid dynamics. METHODS Idealized portal vein(PV) system models were reconstructed with different angles of the PV-splenic vein(SV) and superior mesenteric vein(SMV)-SV. Patient-specific models were created according to enhanced computed tomography images. WSS was simulated by using a finite-element analyzer, regarding the blood as a Newtonian fluid and the vessel as a rigid wall. Analysis was carried out to compare the WSSin the portal hypertension group with that in healthy controls.RESULTS For the idealized models, WSS in the portal hypertension group(0-10 dyn/cm2) was significantly lower than that in the healthy controls(10-20 dyn/cm2), and low WSS area(0-1 dyn/cm2) only occurred in the left wall of the PV in the portal hypertension group. Different angles of PV-SV and SMV-SV had different effects on the magnitude and distribution of WSS, and low WSS area often occurred in smaller PV-SV angle and larger SMV-SV angle. In the patient-specific models, WSS in the cirrhotic patients with portal hypertension(10.13 ± 1.34 dyn/cm2) was also significantly lower than that in the healthy controls(P < 0.05). Low WSS area often occurred in the junction area of SV and SMV into the PV, in the area of the division of PV into left and right PV, and in the outer wall of the curving SV in the control group. In the cirrhotic patients with portal hypertension, the low WSS area extended to wider levels and the magnitude of WSS reached lower levels, thereby being more prone to disturbed flow occurrence.CONCLUSION Cirrhotic patients with portal hypertension show dramatic hemodynamic changes with lower WSS and greater potential for disturbed flow, representing a possible causative factor of PV thrombosis.

Protection mechanism of deacetylase inhibitor on spleen of rats with severe hemorrhagic shock

Objective: To explore the protection and molecular mechanism of histone deacetylase inhibitors(HDACIs) on the spleen of rats with hemorrhagic shock. Methods: A total of 60 SPF male SD rats were selected for the modeling of severe hemorrhagic shock using the method of arterial and venous cannulation with the time-divided bleeding. The measurement of mean arterial blood pressure and blood lactic acid was used to verify the modeling. The modeled rats were randomly divided into shock group, shock+suberoylanilide hydroxamic acid(SAHA) group, shock+autogenous transfusion group, and shock+SAHA+autogenous transfusion group. Three hours after the treatment, the spleen of rats was collected and TUNEL method was employed to detect the apoptosis of spleen cells in each group. Afterwards, real-time PCR and western blot were employed to detect the expression of BCL-2, BAX, and caspass3 in the spleen of rats in each group. Results: A total of 55 rats had successful modeling of severe hemorrhagic shock, with success rate of 92%. Cell apoptosis in the severe hemorrhagic model group was the most serious. After the intervention of HDACIs and the autogenous transfusion, the tissue injury was a bit recovered. Cell apoptosis was least in the shock+SAHA+autogenous transfusion group(P<0.05). After the intervention of HDACIs and the autogenous transfusion, the relative expression of BCL-2 was significantly increased(P<0.05), with highest relative expression of BCL-2 in shock+SAHA+autogenous transfusion group(P<0.05). After the intervention of HDACIs and the autogenous transfusion, the relative expression of BAX was significantly decreased(P<0.05), with lowest relative expression of BAX in the intervention group of single HDACIs. The change in the expression of caspass3 was similar to BAX, namely the relative expression of caspass3 was significantly decreased after the intervention of HDACIs and the autogenous transfusion(P<0.05). Conclusions: HDACIs and autogenous transfusion can all protect the spleen injury because of the severe hemorrhagic shock. Its molecular mechanism may be related to the regulation on the expression of BCL-2/BAX and caspass3, which may affect the apoptosis process of cells.

Transmission patterns of COVID-19 in the mainland of China and the efficacy of different control strategies: a data-and model-driven study

Background:The coronavirus disease 2019(COVID-19)outbreak has seriously endangered the health and lives of Chinese people.In this study,we predicted the COVID-19 epidemic trend and estimated the efficacy of several intervention strategies in the mainland of China.Methods:According to the COVID-19 epidemic status,we constructed a compartmental model.Based on reported data from the National Health Commission of People's Republic of China during January 10-February 17,2020,we estimated the model parameters.We then predicted the epidemic trend and transmission risk of COVID-19.Using a sensitivity analysis method,we estimated the efficacy of several intervention strategies.Results:The cumulative number of confirmed cases in the mainland of China will be 86763(95%CI:86067-87460)on May 2,2020.Up until March 15,2020,the case fatality rate increased to 6.42%(95%CI:6.16-6.68%).On February 23,2020,the existing confirmed cases reached its peak,with 60890 cases(95%CI:60350-61431).On January 23,2020,the effective reproduction number was 2.620(95%CI:2.567-2.676)and had dropped below 1.0 since February 5,2020.Due to governmental intervention,the total number of confirmed cases was reduced by 99.85%on May 2,2020.Had the isolation been relaxed from February 24,2020,there might have been a second peak of infection.However,relaxing the isolation after March 16,2020 greatly reduced the number of existing confirmed cases and deaths.The total number of confirmed cases and deaths would increase by 8.72 and 9.44%,respectively,due to a 1-day delayed diagnosis in non-isolated infected patients.Moreover,if the coverage of close contact tracing was increased to 100%,the cumulative number of confirmed cases would be decreased by 88.26%on May 2,2020.Conclusions:The quarantine measures adopted by the Chinese government since January 23,2020 were necessary and effective.Postponing the relaxation of isolation,early diagnosis,patient isolation,broad close-contact tracing,and strict monitoring of infected persons could effectively control the COVID-19 epidemic.April 1,2020 would be a reasonable date to lift quarantine in Hubei and Wuhan.

Neuroimaging Features of Pituicytomas

Pituicytoma is a distinct low-grade glioma arising from pituicytes of the neurohypophysis and infundibulum. Due to the rarity of this tumor, most of the reported cases in the literature were originally misdiagnosed as pituitary adenoma, meningiomas, and craniopharyngioma. It is of vital importance to accurately identify this tumor because this tumor, unlike pituitary adenomas, is prone to heavy bleeding during the surgical resection.