Volume 93  ·   Issue 12  ·  2013

To explore the expression and pathological features of insulin-like growth factor-Ⅱ (IGF-Ⅱ) in tissues and sera of hepatocellular carcinoma (HCC) patients and the siRNA-mediated inhibition of IGF-Ⅱ mRNA transcription in human HepG2 cells.

From December 2009 to August 2010, the self-control HCC, paracancerous and distal cancerous tissues were collected to analyze the expression of IGF-Ⅱ.The serum levels of IGF-Ⅱ expression were detected for pathological features.IGF-Ⅱ expression in HepG2 cells was intervened by siRNA.IGF-Ⅱ mRNA or IGF-Ⅱ level and analyzed by reverse transcription-polymerase chain reaction (RT-PCR), real-time PCR or enzyme-linked immunosorbent assay (ELISA).And the ratio of cell apoptosis was analyzed by EdU/Hoechst33342.

The levels of IGF-Ⅱ expression in HCC tissues at mRNA (100%,30/30) or protein (83.3%, 25/30) were significantly higher (P<0.01) than those in para-cancerous (46.7%, 53.3%) or distal cancerous tissues (0, 0).The serum level of IGF-Ⅱ was significantly higher in HCC patients (3.74±0.67) ng/L than that in cases with benign liver diseases (1.93±0.17) ng/L and controls (1.14±0.14) ng/L (P<0.001).The expression of IGF-Ⅱ in the HCC group was associated with HBV infection (t=5.390, P<0.001).After siRNA transfection, the expression of IGF-Ⅱ decreased significantly in HepG2 cells at mRNA or protein levels.The down-regulated expression of IGF-Ⅱ was dependent on the dose and time of IGF-Ⅱ siRNA.And the apoptotic index of HepG2 cells and the sensitivity to adriamycin both increased.

The expression of IGF-Ⅱ is closely associated with the progression of HCC.And the intervening of its transcription may promote apoptosis and sensitize to adriamycin.

To explore the clinical value of miRNA-29b expression and the combined detection of serum miRNA-29b and alpha-fetoprotein (AFP) in the diagnosis of primary hepatic carcinoma (PHC).

From January 2007 to May 2010, the serum levels of miRNA-29b and AFP from 96 healthy controls and 87 PHC patients were measured by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) respectively.The relationship of miRNA-29b and various clinical parameters was analyzed.

Serum levels of miRNA-29b in PHC pre-operative group (0.250 (0.124-0.381)) significantly decreased versus the control group[0.860 (0.587-1.338)]and the post-operative group (0.890 (0.637-1.414)) (P<0.001).Also, the levels of AFP in PHC pre-operative group (65.4 (20.1-212.3)) was obviously higher than that in the control group (13.3 (7.1-19.8)) and the post-operative group (23.2 (11.6-55.7)) (P<0.001).A lower expression of miRNA-29b was correlated with lower differentiation and higher TNM stages (P<0.045, P<0.001).Kaplan-Meier curve analysis revealed that PHC patients with a low serum expression of miRNA-29b had a significantly shortened overall survival when compared with a high serum expression of miRNA-29b (25.52 vs 36.94 months,P=0.008).Multivariable Cox regression analysis indicated that the serum expression of miRNA-29b was an independent risk factor for overall survival.Relative risk was 0.482 (95% confidence interval:0.236-0.985).The critical values for miRNA-29b and AFP were determined at 0.38 and 23.1μg/L through the ROC curves.Under the critical value, the sensitivity of miRNA-29b and AFP were 75.9% and 70.1% and the specificity of miRNA-29b and AFP 89.5% and 92.7% respectively.Combined detection could increase the sensitivity up to 87.3%, and achieve a specificity of 88.5%.

The combined detection of miRNA-29b and AFP aids the diagnosis of PHC and the prediction of its prognosis.

To explore the expression of microRNA-155 in hepatocellular carcinoma (HCC) and its contribution to recurrence and prognosis of HCC after liver transplantation (LT).

The expression levels of microRNA-155 in 100 HCC samples were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR).Kaplan-Meier and Cox proportional regression analyses were utilized to determine the association of microRNA-155 expression with patient survivals.

The expression levels of microRNA-155 were higher in primary HCC patients with post-LT recurrence (n=45, mean relative level=14.94) than those with non-recurrence (n=55, mean relative level=4.70)(P=0.001) and correlated with micro-vascular invasion of HCC tissue samples (P=0.001).The patients with a higher expression of microRNA-155 had significantly worse recurrence-free survival (RFS: (21.5±3.2) months, log rank P<0.001) and overall survival (OS: (29.3±3.2) months, log rank P<0.001) than those with a lower expression of microRNA-155 (RFS: (50.8±3.2) months; OS: (54.6±3.5) months).Multivariate analysis revealed that a high expression of miR-155 was an independent prognostic predictor.

MicroRNA-155 is over-expressed in primary HCC with tumor recurrence and may serve as a novel biomarker for tumor recurrence and survival of HCC patients after L T.The detection of microRNA-155 is of clinical significance in HCC.

To explore the change pattern of carotid stiffness and its relationship between intima-media thickness (IMT) in type 2 diabetes mellitus (T2DM).

Quantitative intima-media thickness (QIMT) and quantitative arterial stiffness (QAS) were performed on bilateral carotids of 72 T2DM patients in May 2009 and February 2011 separately.IMT, compliance coefficent (CC),α,β and pulse wave velocity (PWV) were measured.Their relationship was analyzed.

Comparing with ultrasound result in 2009, CC of bilateral carotids increased (left 0.9±0.4 vs 1.1±0.4, P=0.016; right 1.1±0.5 vs 1.2±0.5, P=0.012).IMT increased while α,βand PWV decreased (P>0.05) in 2011.No correlation existed between carotid IMT and QAS parameters.

The glycemic,lipid and blood pressure controls decrease the carotid stiffness of patients with T2DM.Carotid IMT and stiffness.

To explore the clinical feasibility of accelerated partial breast irradiation (APBI) by intensity-modulated radiotherapy (IMRT).

Twenty-six patients with T1N0M0 breast cancer were enrolled into a prospective accelerated partial-breast IMRT protocol between January 2008 and January 2010.Inverse planning of IMRT was employed at a prescribed dose of 34 Gy/10 f/5 d.Acute radiation skin responses and clinical effects were observed.

All of them completed radiation.During the radiation, Grade 1 of acute radiation skin reaction (mild hyperpigmentation) was seen in 8 patients and there was not>grade 2 of skin reaction.At Month 1 post-radiation, Grade 1 of acute radiation skin reaction (mild hyperpigmentation) was seen in all patients and there was not>grade 2 of skin reaction.At Month 3 post-radiation, all instances of acute radiation skin reactions recovered.The median follow-up period was 51 months (range:35-59).The follow-up period of 23 patients were over 3 years.No local recurrences developed.The 3-year disease-free survival was 100%.Cosmesis was good or excellent in all cases at Year 2.

External beam-partial breast irradiation delivered by IMRT is feasible for selected Chinese early-stage breast cancer patients after breast-conserving surgery.The cosmetic effect,local control rate and longterm survival rate are satisfactory.And acute radiation toxicity is quite low.

To study the effects of using auto-scalp for repairing donor site of thickness from cicatricial skin with auto-scalp grafting.

A total of 13 cases with donor site of thickness from cicatricial skin from January 2011 to December 2011 were analyzed.Wounds of donor site from cicatricial skin were grafted with auto-scalp and scalp were fixation was applied with negative pressure.The survival rate of auto-scalp graft was observed at Day 7 post-operation.At Month 12, hyperplastic scars at these donor sites of cicatricial skin were assessed through Vancouver Scar Assessment Table, scar itch assessment and scar proliferation rate.Wounds in the other thirteen cases with donor site of thickness from cicatricial skin from January 2010 to December 2010 were covered with vaseline gauze as control.

No significant difference existed in the gender and age of the two groups patients (P>0.05).The auto-scalp graft all survived.And the average healing time of donor-site wound in cicatricial skin in grafting group (7 days) was significantly decreased than that of control group (a mean of 20 days) (P<0.01).After followed up for twelve months, the scar formation assessment value (1.5±0.5), scar itch assessment (1.2±0.4) and scar proliferation rate (14.6%±7.6%) in grafting group were significantly less than those of control group (6.7±1.1, 2.0±0.7, 55.8%±12.2%, all P<0.01).

Auto-scalp grafting may greatly shorten the healing procedure and ameliorate the quality of donor-site of thickness from cicatricial skin.

To explore the association between clopidogrel resistance (CR) as assessed by whole blood electrical impedance aggregometry (EIA) and platelet parameters.

The prospective study comprised 152 patients with coronary artery disease (CAD) on the therapy of clopidogrel.EIA employed adenosine diphosphate (ADP) as an inductor to measure platelet aggregation.CR was defined by spontaneous aggregation (electrical impedance≥10Ω).The subjects were divided into 2 groups of CR and clopidogrel sensitive (CS).Platelet parameters were measured by routine blood test.And their clinical data and outcomes were analyzed.

The prevalence of CR was 10.5% (n=16).The ratio of patients with diabetes in CR group was higher than that in CS group (7/16 vs 29/136, P=0.046).Platelet counts and mean platelet volume (MPV) were also higher in CR group than those in CS group ((241±58) ×10⁹/L vs (185±56) ×10⁹/L, (8.0±0.8) fl vs (7.4±0.9) fl, both P<0.05).Logistic regression indicated each 10×10⁹/Lincreasein platelet and each 1 fl increasein MVP were associated with 0.376 and 1.015 folds increase in CR onset respectively (OR=1.376, 95% CI 1.097-1.725,P=0.006;OR=2.015, 95% CI 1.148-3.537, P=0.015).The patients with CR had more cardiovascular events during an average follow-up of 53 months (6/16 vs 23/136,P=0.047).

CAD patients with CR had higher incidence of cardiovascular events.Increased platelet counts and MPV levels are independent predictors for CR in CAD patients.

To explore the association between the -511C/T,-31T/C and +3954C/T polymorphisms of interleukin-1B (IL-1B) gene and chronic obstructive pulmonary disease (COPD) using the method of meta-analysis.

Comprehensive searches were performed of Pub Med, Embase, Ovid, Wanfang and Chinese journal full-text database to retrieve the related casecontrol studies.The pooled odds ratios were performed respectively for allele comparison, additive genetic model, dominant genetic model and recessive genetic model and subgroup analysis was also performed by ethnicity.

Seven case-control studies were included for meta-analysis.Pooled analysis showed that neither-511C/T,-31T/C nor +3954C/T polymorphisms increased the susceptibility to COPD.In the subgroup analysis by ethnicity, significant risks were found in the Caucasian population for-511C/T T allele (OR=1.76,95% CI 1.22-2.54,P=0.002), but not in the Asian population (OR=0.94, 95% CI 0.64-1.38, P=0.736).Significant risks were also found in the Caucasian population for-31T/C C allele (OR=0.62, 95% CI 0.40-0.97, P=0.035), but not in the Asian population (OR=1.06, 95% CI 0.89-1.26, P=0.533).

IL-1B polymorphisms may play a role in the susceptibility of COPD in an ethnicity-specific manner.In the Caucasian population, the risk of COPD was associated positively with the IL-1B-511C/T T allele and negatively with the IL-1B-31T/C C allele.

To explore the associations of preoperative plasma levels of fibrinogen and D-dimer with clinicopathologic parameters and overall survival in colorectal cancer patients after curative resection.

From January 2002 to December 2003, a total of 341 colorectal cancer patients underwent curative resection.And their relevant clinical data were reviewed.The median age was 58 years (range:23-90 years) and the median follow-up period was 64 months (range:5-89 months).The preoperative plasma levels of fibrinogen and D-dimer were examined, the correlation of clinicopathologic findings and overall survival was analyzed.A Log-rank test was used for univariate analysis and a Cox regression model for multivariate analysis.

The preoperative plasma levels of fibrinogen and D-dimer were (3.7±0.7) g/L and (0.49±0.18) mg/L respectively.Elevated plasma levels of fibrinogen were associated with advanced tumor stage (P=0.008), venous invasion (P=0.006), postoperative distant metastases (P<0.01) and lymph node involvement (P=0.001), but not with histologic grade (P=0.232), and invasion depth (P=0.253).The overall survial is 64.5% (220/341).Elevated plasma levels of D-dimer were associated with advanced tumor stage (P=0.013), invasion depth (P=0.007) and lymph node involvement (P=0.001), but not with histologic grade (P=0.082), venous invasion (P=0.746) or postoperative distant metastases (P=0.131).Multivariate analysis showed that preoperative plasma levels of fibrinogen (P=0.029), histologic grade (P=0.001), and lymph node involvement (P=0.001) were independent prognostic factors.

High preoperative plasma levels of fibrinogen and D-dimer are associated with clinicopathologic parameters.And a high preoperative plasma level of fibrinogen is associated with distant metastases and poor prognosis after curative resection in colorectal cancer patients.

To explore the hematologic adverse effects in patients with renal cell carcinoma treated with sunitinib.

A total of 136 patients with advanced renal cell carcinoma were treated with sunitinib at our hospital from 2008 to 2011.There were 91 males and 45 females with an average age of 55.5 years.They received sunitinib in repeated 6-week cycles consisting of 4 weeks of sunitinib 50 mg per day followed by 2 weeks of treatment (schedule 4/2).The hematologic toxicities, collected at baseline and 14, 28, 42 (after a 2-week rest period) days, were graded according to the National Cancer Institute common terminology criteria for adverse events version 3.0.The paired Wilcoxon test was used to evaluate the kinetics of hematologic adverse effects at days 14, 28, and 42 post-treatment.

The hematologic toxicities included leukopenia (n=91,66.9%), neutropenia (n=95, 69.8%), lymphopenia (n=58, 46.2%), thrombopenia (n=89, 65.4%) and hypohemoglobinemia (n=48, 35.3%).Among them, 31cases (22.8%) had the high-grade (including grades 3 and 4) toxicity of thrombopenia.There were depressions in hematopoietic cell populations including leukocytes, neutrophils, and platelets at days 14, 28 and 42 versus the baseline level (all P<0.05).The median hemoglobin level transiently increased at days 14 and 28 (both P<0.01) and returned to the level of baseline at days 42 (P=0.754).

The incidence of hematologic adverse effects of sunitinib slightly varies with what have been observed in previous studies.And the incidence of high-grade toxicity of thrombocytopenia is higher than that reported in studies conducted in the US and Europe.

To determine the incidence and the predictors of diabetes ketoacidosis (DKA) in Chinese type 1 diabetics so as to lay a foundation for better prevention and treatment.

For this cross-sectional study,a total of 611 patients with established type 1 diabetes between August 6, 2010 and March 31, 2012 were recruited from 16 hospitals in Guangdong Province.And 491 of them were over 18 years old.A data entry form was used to collect the patient information on demographics, medical history, acute/chronic complications, smoking/drinking status, diet, exercise, physical examination and treatment,etc. Hemoglobin A_1c (HbA_1c) and stimulated C peptide levels were centrally measured.The incidence rate of diabetic ketoacidosis (DKA) was calculated at events per 100 patient-years.To determine the predictors of DKA, Poisson′s regression model was used for analysis.And backward stepwise logistic regression analysis was performed to identify the predictors of DKA recurrence.The protocol and informed consent form were approved by Ethics Committee of Third Affiliated Hospital, Sun Yat-sen University.Written informed consent was obtained from patients (age>18 years) or their legal guardians (age<18 years).

Among them, 53.7% were females.The mean age was 27.8 years (range: 19.5-37.3).The age of onset was 22.7 (14.0-31.4) years old and disease duration 4.3 (1.7-7.9) years.Overweight and obese patients accounted for 10.8% and 1.0% respectively.Among them, the self-monitoring frequency of blood glucose was 0.4 (0.1-1.4) times per day.Overall, 26.4% patients reached the target of agespecific HbA 1c values.The overall incidence of DKA was 26.4 per 100 patient-years.Significant predictors of DKA in the Poisson regression model were females (RR=2.12), medical insurance claiming percentage below 50% (RR=1.84), uncontrolled diet (never controlled diet vs.usually controlled diet, RR=1.76), smoking (RR=2.18) as well as worse glycemic control (HbA_1c per 1.0% increment,RR=1.15).Totally,34.4% of DK A episodes occurred in 3.8% of type 1 diabetics with recurrent events (no less than 2 episodes).The recurrence of DKA was associated with females (RR=10.56),smoking (RR=6.99), worse beta cell function (stimulated C peptide per 100 pmol/L decrement, RR=4.88) and worse glycemic control (HbA_1c per 1.0% increment, RR=1.16).

There is a high incidence of DKA in Chinese type 1 diabetics.And it is recurrent in highrisk patients.Comprehensive management should be offered to control modifiable risk factors in these patients.

To explore the effects of intraperitoneal injection of mesenchymal stem cells (MSC) on intestinal barrier in serve acute pancreatitis (SAP) rats.

MSC were harvested and cultured from femurs of one male SD rat.And 30 female SD rats were divided into 3 groups:control group (n=6),SAP group (n=12) and MSC transplantation group (n=12).SAP was induced by intraperitoneal injection of L-arginine (2 g/kg) twice in SAP and MSC groups.In MSC group, the third-generation MSC (5×10⁶) were injected intraperitoneally once daily for 3 days.All rats were sacrificed after 72 h.The histomorphologic alternations of small intestine were measured to evaluate the therapeutic effect of MSC transplantation.Reverse transcription (RT) -PCR were used to identify the expression of TNF-α mRNA and IL-1β mRNA in small intestine and pancreas.Small intestine and pancreatic samples were examined for the engraftment of donor-derived MSC by Y chromosome in situ hybridization analysis.

Compared with SAP group, histomorphologic alternations of small intestine significantly lower in MSC group (4.17±0.28 vs 3.00±0.33,P<0.05).The relative expression quantity of T NF-α mRNA and IL-1β mRNA in pancreas were both significant higher in SAP and MSC groups than those in control group (3.10±0.73 and 1.92±0.37 vs 0.51±0.24, 4.60±0.59 and 2.43±0.39 vs 1.15±0.18, all P<0.05).Compared with SAP group, the expression quantity of TNF-α mRNA and IL-1β mRNA in pancreas significantly lower in MSC group (both P<0.05).The relative expression quantity of TNF-α mRNA and IL-1β mRNA in small intestine were both significant higher in SAP and MSC groups than those in control group (2.73±0.91 and 1.55±0.48 vs 0.62±0.20,5.20±0.94 and 2.10±0.34 vs 0.99±0.10, all P<0.05).The expressions of TNF-α mRNA and IL-1β mRNA in MSC group were lower than those in SAP group (both P<0.05).Sry gene was not detected in pancreatic and intestinal tissue of MSC-treated rats.

Syngraft MSC exert protective effects on pancreas and small intestine injury.And their beneficial effects are primarily mediated via indirect actions but not by their differentiation into target cells.

To explore the protective effect of lipoxin (LX)A₄ during myocardial ischemia reperfusion injury (MIRI) and discuss the molecular mechanism of excessive endoplasmic reticulum stress (ERS) in rats.

Seventy-two male SD rats were divided into 6 groups, according to random number table,12 in each group:sham operation group (group sham) 1,2:injected with normal saline (NS) 2 ml/kg before and after coronary artery threading.MIRI group (group I/R) 1,2: injected with NS 2 ml/kg before and after MIRI.Group LX1, L X2:injected with LXA₄100μg/kg in 2 ml/kg NS before and after MIRI treatment.After the rat MIRI model was established, the serum concentrations of tropoin I (cTnI) were measured in each group before open-chest operation (T₁) and at the end of the experiment (T₂).Besides,expressions of GRP-78, caspase-12 protein and mRNA were test.At the same time, myocardial cell apoptosis, the myeloperoxsidase (MPO), superoxide dismutase (SOD) activation and malondialdehyde (MDA) content were detected while the HE and ultrastructural changes of cardiac muscle were observed.

The expression levels of GRP-78, caspase-12 protein and mRNA, apoptotic index, serum c TnIconcentrations (T₂) and MPO, SOD activation, MDA content were all significantly higher in groups I/R and LX than those in group sham 1 and sham 2 (all P<0.05).The expression levels of GRP-78, caspase-12 protein in group LX1 (compared with group I/R1) and in group LX2 (compared with group I/R2) were all significantly lower (all P<0.05).Besides, the expression of GRP-78, caspase-12 m RNA in group L X1 were significantly less than those in group I/R1 ((0.86±0.06)×10⁵ vs (1.95±0.65)×10⁵, (12.35±4.15)×10⁵vs (23.76±6.57)×10⁵, both P<0.05),so were thoes in groups LX2 and I/R2 ((0.64±0.05)×10⁵vs (2.36±0.57)×10⁵, (7.04±0.81)×10⁵vs (26.49±6.82)×10⁵, both P<0.05).The apoptotic index, the serum concentrations of cTnI (T₂), MPO activation and MDA content were all significantly lower in group LX1 than those in group I/R1 (34.6%±5.7% vs 52.5%±6.4%, (293±22) vs (581±44) ng/L, (176±47) vs (331±94) U/g tissue, (1549±238) vs (2403±439) nmol/g protein, both P<0.05), so were those in groups LX2 and I/R2 (26.5%±4.6% vs 54.8%±6.3%, (207±29) vs (593±61) ng/L, (99±24) vs (329±92) U/g tissue, (1055±237) vs (2422±518) nmol/g protein, all P<0.05).In addition, the activity of SOD in groups LX1 and LX2 were both significantly higher respectively than those in groups I/R1 and I/R2 (both P<0.05).Moreover, compared with groups I/R1 and I/R2, the neutrophils infiltration were significantly less than those in groups LX1 and LX2 respectively, and the ultrastructure damage were also much milder.

Before and after MIRI, application of LXA₄may significantly inhibit neutrophil infiltration and attenuate myocardial oxidative injury. LXA₄play its role in myocardial protection via down-regulating the expression of GRP-78, caspase-12 and the inhibition of excessive ERS.

To explore the role of voltage dependent anion channel 2 (VDAC2) involved mitochondrial apoptosis in heart injury of rats with severe scald injury and elucidate its possible regulatory signal pathway.

A total of 60 Wistar rats were divided into sham scald group (n=30) and scald group (n=30) according to a random digital table.Blood and heart tissue samples were harvested at Day 1, 7, 14 post scalding.Myocardial injury was assessed with cardiac troponin I (cTnI) by enzyme-linked immunosorbent assay (ELISA).Mitochondrial apoptosis activation was evaluated by the expressions of Bax/Bcl-2 ratio, cytoplasmic cytochrome C and VDAC2.And the levels of phosphatidylinositol 3-kinase, p-Glycogen Synthase Kinase-3β and hexokinase 2 protein were determined by Western blot.

The serum levels of c TnI were significantly higher in scald group than those in sham scald group at Day 1, 7, 14 ((1.41±0.25) vs (0.53±0.23) μg/L, (1.93±0.53) vs (0.43±0.23) μg/L, (1.62±0.34) vs (0.41±0.22) μg/L respectively, all P<0.05).Compared with sham scald group, Bax/Bcl-2 ratio increased significantly in scald group at Day 1,7 day post-scalding (3.360±0.173 vs 0.623±0.044,2.736±0.341 vs 0.698±0.064, 1.290±0.234 vs 0.718±0.063 respectively, all P<0.05), VDAC2 protein level in scald group decreased significantly at Day 1, 7, 14 (0.070±0.009 vs 0.328±0.026, 0.007±0.002 vs 0.291±0.025, 0.009±0.004 vs 0.302±0.037 respectively, all P<0.05), the cytoplasmic levels of cytochrome increased significantly in scald group at Day 1, 7, 14 (0.418±0.030 vs 0.022±0.007, 1.685±0.169 vs 0.030±0.011, 0.300±0.037 vs 0.098±0.014 respectively, all P<0.05), the expression of PI3K was significantly lower in scald group at Day 14 post-scalding (0.083±0.015 vs 0.328±0.011, P<0.05), the expressions of p-GSK3βall reduced significantly at Day 1, 7, 14 (0.098±0.014 vs 0.446±0.031, 0.064±0.002 vs 0.476±0.054、0.074±0.010 vs 0.442±0.041, respectively, all P<0.05) and the expressions of HK2 were lower at Day 7,14 post-scalding (0.390±0.027 vs 0.611±0.070, 0.267±0.018 vs 0.490±0.042, respectively, all P<0.05).

VDAC2 involved mitochondrial apoptosis is activated in myocardium after severe scalds.And it may be regulated by the pathway of PI3K-GSK-HK2.

To explore the effects and mechanisms of Ghrelin on hypertension and insulin resistance in fructose-fed rats.

A total of 32 male Sprague-Dawley (SD) rats were randomized into control (A) and fructose-fed groups (B).Rats in group B were fed with 10% fructose solution for 4 weeks.Then the rats in group A were randomized into intraperitoneal saline (group GA1) or intraperitoneal 50 nmol/kg Ghrelin (group GA2) and those in group B into intraperitoneal saline (group GB1) or intraperitoneal 50 nmol/kg Ghrelin (group GB2) twice daily for 6 weeks.Caudal arterial pressure was measured weekly.Plasma blood glucose, insulin concentration and lipid profile were measured.And insulin resistance (IR) was calculated by the method of homeostasis model assessment (HOMA).Plasma level of 15-F2t-isoprostane was measured by enzyme-linked immunosorbent assay (ELISA).

Ghrelin caused a significant reduction of systolic pressure at Week 3 in group GB2 versus group GB1 (P<0.05).Maximal effect appeared at Week 5 ((127±5) vs (120±6) mm Hg,P<0.05,1 mm Hg=0.133 kPa), but blood pressure failed to reach normal value.Ghrelin also decreased plasma insulin concentration and HOMA-IR ((9.6±2.6) vs (13.1±3.6) μU/ml, P<0.05;1.92±0.12 vs 2.78±0.14, P<0.01).Plasma level of 15-F2t-isoprostane was lower in group GB2 than that in group GB1 ((75±11) vs (102±14) pg/ml, P<0.01).

Ghrelin may lower blood pressure, ameliorate insulin resistance and improve insulin sensitivity through inhibiting oxidative stress in fructose-induced rats.

To explore the effects of iron overload on umbilical cord derived mesenchymal stem cells (UC-MSC) and elucidate the involvement of reactive oxygen species (ROS) in this process.

The iron overload model of MSC was established by in vitro addition of ferric ammonium citrate (FAC) into culture medium.Cell proliferation and apoptosis were determined by Annexin V/PI double staining and population doubling time (DT) respectively.Co-culture system was used to assess the hematopoietic support capacity of UC-MSC in different groups.Thereafter the ROS level was detected with fluorescent probe 2′,7′-dichlorofluorescin diacetate (DCFH-DA).And the ROS related signaling factors of p-p38MAPK, p38 MAPK, P53 were measured by Western blot.

(1) The DT of UC-MSC in iron overload group was significantly longer than that of control ((24.43±2.72) h vs (16.03±2.31) h,P<0.05).But the difference was insignificant after two passages (P>0.05). (2) Apoptosis in iron overload group was higher than that of control (12.75%±0.32% vs 3.63%±0.80%, P<0.05). (3) The colony forming capacity of mononuclear cell (MNC) co-cultured with UC-MSC of iron overload group for 1/2 weeks significantly decreased. (4) The ROS level of UC-MSC with iron overload was higher than that of control in time and concentrationdependent fashions and it peaked at 400μmol/L of FAC for 12 h (1499±86 vs 548±97,P<0.05). (5) The expressions of p-p38MAPK and P53 increased in response to FAC compared with control.But such an effect was partially inhibited after the use of antioxidants.

Iron overload may impair the proliferation, survival and hematopoeisis supportive function of UC-MSC by enhancing the generation of ROS.And ROS stimulates the signaling pathways of p-p38MAPK and P53.