ABSTRACT
Purpose Lipotoxicity plays an important role in the progression of diabetes and its complications,and the gold standards for organs' lipid quantification are biopsy or histochemical staining,which are invasive and have their own limitations.Thus,our research was to identify the difference in organ lipid deposition between type 2 diabetic patients and healthy volunteers by using noninvasive three-point T2* corrected Dixon imaging.Materials and Methods Sixty-five type 2 diabetic patients and 34 healthy volunteers were included in this study.All participants underwent three-echo Dixon with 3.0T MR imager.Dixon imaging parameters [hepatic fat fraction (HFF),splenic fat fraction (SFF),pancreatic fat fraction (PFF)] were collected.All of the MRI parameters were compared.The relationship between HFF,SFF,PFF and BMI,age were analyzed.Results The hepatic and splenic lipid percentage in diabetic group [HFF=(5.4±4.3)％;SFF=(3.7± 1.4)％] was significantly higher than healthy volunteers group [HFF=(2.9± 1.3)％;SFF=(3.0± 0.9)％;P＜0.05,respectively].However,there was no significant difference in pancreatic fat fraction between diabetic and healthy groups (P＞0.05).There were positive correlations between HFF,SFF,PFF and BMI (r=0.379,0.305 and 0.306,P＜0.05).Moreover,only the positive correlation between pancreatic fat fraction and age were observed (r=0.261,P＜0.05).Conclusion The three-point T2* corrected Dixon revealed the abnormalities of hepar and spleen lipid accumulation in diabetic patients.Thus,the three-point Dixon imaging may potentially aid in evaluating the lipid deposition of abdominal organs.
ABSTRACT
Purpose To study the effects of α-tocopherol on activator protein-1(AP-1)binding and TGF-β1 expression induced by high glucose in rat mesangial cells and further to clarify the molecular mechanism of antioxidant in treating diabetic nephropathy. Methods AP-1 binding of the rat mesangial cells exposed to high glucose was detected by gel shift assay.The Jun,Fos compositions of AP-1 dimer were determined by supershift assay.Protein expression of TGF-β1 was detected by Western blot.Additionally,the effects of α-tocopherol on AP-1 binding and TGF-β1 expression induced by glucose in rat mesangial cells were also studied. Results High glucose stimulated AP-1 binding of mesangial cells in time-and-dose-dependent manners .This AP-1 binding increase involved JunD and Fos as shown by gel supershift.Glucose also increased protein expression of TGF-β1 at same time.The increased AP-1 binding and TGF-β1 were inhibited with pretreatment with α-tocopherol in glucose-treated mesangial cells. Conclusions This study suggests that α-tocopherol can significantly inhibit AP-1 activity and TGF-β1 expression by glucose in rat mesangial cells,which may be one of its antioxidation mechanisms to retard diabetic nephropathy.
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Objective To investigate the possible role of protein kinase(PK) activity in the induction of AP-1 by ox-LDL in mesangial cells and to elucidate the upstream signal pathways involved in the ox-LDL-induced AP-1 binding. Methods Rat mesangial cells were randomly divided into the normal cells, ox-LDL-treated cells and PK inhibitor + ox-LDL-treated cells. Treatments with the PKC inhibitor bisindolylmaleimide I, the PKA inhibitor H89, the PTK inhibitor genistein (GEN), the MEKi inhibitor PD98059, or the p38 MAPK inhibitor SB203580 were applied prior to a 24-hour incubation of ox-LDL in mesangial cells. The phosphorylation of MAPK families was detected by Weatern blot analysis. AP-1 binding was determined by gel shift assay. Results Ox-LDL stimulated the phosphorylation of JNKi/SAPK and p38 MAPK( P 0. 05) . Bisindolylmaleimide I at 50, 100, 200 nmol/L appreciably reduced the ox-LDL-induced AP-1 binding. H89 at 0. 5, 5 umol/L significantly inhibited AP-1 binding by ox-LDL. GEN at 25, 50 umol/L did not reduce the AP-1 binding by ox-LDL, but when GEN rose up to 100 umol/L, the ox-LDL-induced AP-1 binding significantly decreased in mesangial cells. However, SB203580 and PD98059 did not reduce the ox-LDL-induced AP-1 binding in the present study. Conclusion Multiple protein kinases may involve in the stimulation of AP-1 by ox-LDL in mesangial cells.
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Tomato big bud mycoplasma-like organism (TBB-MLO) Tomato spotted wilt virus (TSWV) and P. solanacearum was detected by using ELISA and Dot-ELISA methods. The risults showed that to detect TBB-MLO and P. solanacearum Dot-ELISA was about 50—100 times sensitive than ELISA method, but to detect TSWV it gave same results of both methods.
ABSTRACT
One hind leg(7 %TBSA)of the rat was scalded and the changes of the reduction-oxidation state and protein degradation in the soleus muscle were observed 72 hours postinjury both in vitro and in vivo.It was found that the lactate/pyruvate (L/P) and malate/pyruvate(M/P)ratios of the soleus muscle were significantly lower and the protein degradation rate much higher in the scalded leg than in the unscalded legs and the control.After the addition of insulin to the medium significant elevation of L/P and M/P ratios and reduction of the protein degradation rate in the soleus muscle could be observed.There findings suggest that there is a good correlation between the changes of the reduction-oxidation state and the protein degradation rate in the cytosol of the soleus muscle after scalding in the rat.