1.Assays of immunoreactive insulin and specific insulin in evaluating islet function and insulin sensitivity
Feng LI ; Lihong CHEN ; Juying TANG ; Li YAN ; Yang HE
Chinese Journal of Endocrinology and Metabolism 2008;24(2):184-185
Comparison of assays of immunoreactive insulin (IRI) and specific insulin in evaluating islet β cell function and insulin sensitivity suggested that there were no significant differences in individuals with different glucose tolerance impairment by two assays. The evaluation of islet β cell function using IRI and insulin sensitivity is still valid in clinical practice.
2.Role of Nav1.7 in dorsal root ganglia in a rat model of diabetic neuropathic pain
Changbin KE ; Xiaoxia HUANG ; Yan WANG ; Juying LIU
Chinese Journal of Anesthesiology 2011;31(8):947-949
ObjectiveTo investigate the role of Nav1.7 in dorsal root ganglia (DRG) in a rat model of diabetic neuropathic pain (DNP).MethodsThirty-two female Wistar rats aged 3 months weighing 180-220 g were randomly divided into 4 groups ( n = 8 each):control group ( group C),sham operation group ( group S),DNP group and ProTx- Ⅱ (a selective Nav1.7 blocker) group (group E).Diabetes mellitus was induced by intraperitoneal streptozocin 65 mg/kg.Blood glucose level and mechanical paw withdrawal threshold (MWT)to von Froy filamentstimulation were measured 2 weeks later.DNP was confirmed by blood glucose level ≥ 16.0 mmol/L and MWT decreased by more than 50% of the baseline value.Intrathecal catheter was implanted at L5,6 interspace on day 10 after successful induction of DNP.On day 4 after placement of the intrathecal catheter,ProTx- Ⅱ 10 μg/kg was injected intrathecally in group E,while the equal volume of normal saline was given in groups DNP and S.MWT and never conduction velocity (NCV) were measured 1 h after intrathecal injection.The rats were then sacrificed and DRGs of the lumbar segment (L4-6) were removed for determination of Nav1.7 protein expression (by immuno-histochemistry and Western blot) and Nav1.7 mRNA expression (by RT-PCR).ResultsThe MWT and NCV were significantly lower and the Nav1.7 mRNA and protein expression was significantly higher in groups DNP and E than in group C.ProTx- Ⅱ significantly attenuated the diabetes-induced changes in MWT,but had no effect on NCV and Nav1.7 mRNA and protein expression.ConclusionNav1.7 in DRG is involved in the maintenance of DNP in rats.
3.Plasma levels of lipoprotein-associated phospholipase A2 and secretory phospholipase A2 in patients with newly diagnosed type 2 diabetes and their relationships to atherosclerosis
Xiuhong LIN ; Mingtong XU ; Lifang MAI ; Juying TANG ; Xiaoyi WANG ; Yan LI ; Li YAN
Chinese Journal of Endocrinology and Metabolism 2016;32(6):470-474
_ Objective_ To evaluate plasma concentrations of lipoprotein-associated phospholipase A2 (LP-PLA2)andsecretoryphospholipaseA2(sPLA2)inpatientswithnewlydiagnosedtype2diabetes,andtoexplore their clinical significance. Methods Oral glucose tolerance test ( OGTT) was carried out in our hospital to all the subjects without history of diabetes. According to the results of OGTT, they were divided into two groups:patients with newly diagnosed type 2 diabetes and subjects with normal fasting glucose and normal glucose tolerance. Anthropometric data such as height, weight, waist circumference, and blood pressure were measured and concentrations of blood glucose, insulin, lipid profile ( including total cholesterol, triglycerides, low density lipoprotein-cholesterol, high density lipoprotein-cholesterol), LP-PLA2, and sPLA2 were determined in both groups. Results Ninety patients with newly diagnosed type 2 diabetes and fifty-eight subjects with normal glucose tolerance were enrolled in our study. As to gender, age, body mass index, blood pressure, and lipid profile, there were no statistically differences between these two groups (P>0. 05). Plasma levels of LP-PLA2 and sPLA2 in diabetic patients were significantly higher than normoglycemic participants [102. 98(76. 34,134. 31) vs 50. 89(23. 71,90. 40) ng/ml, 219. 33 (130. 03,337. 330) vs 78. 55 (75. 15,87. 02) ng/ml, both P<0. 01]. Plasma concentrations of LP-PLA2 and sPLA2 in diabetic patients with atherosclerosis were significantly higher than those without [ 133. 43 ( 111. 54, 145. 17 ) vs 99. 11 ( 63. 02, 130. 85) ng/ml,235. 73 (180. 48, 416. 46) vs 182. 97 (9. 08, 280. 79) ng/ml, both P<0. 05]. LP-PLA2 and sPLA2 were both positively correlated with homeostasis model assessment for insulin resistance (HOMA-IR), while negatively correlated with insulin function index. In a multiple linear regression analysis, LP-PLA2 and sPLA2 were independent correlative factors of HOMA-IR(both P<0. 05). Conclusions Plasma levels of LP-PLA2 and sPLA2 were significantly higher in patients with newly diagnosed type 2 diabetes than in individuals with normal glucose tolerance, even more significant in diabetic patients with atherosclerosis. And their concentrations were both closely related to insulin resistance.
4.Features of lipid ratios in patients with newly diagnosed T2DM and effects of intensive insulin treatment on them
Xiuhong LIN ; Xilin XIONG ; Mingtong XU ; Juying TANG ; Lifang MAI ; Yan LI ; Li YAN
The Journal of Practical Medicine 2017;33(11):1781-1785
Objective To investigate the features of lipid ratios in patients with newly diagnosed T2DM, and the effects of intensive insulin treatment on them. Methods 90 patients with newly diagnosed T2DM and 58 matched people with normal glucose were enrolled to assess height,weight,waist circumference,blood glucose and lipid profiles. BMI,TC/HDL-C,TG/HDL-C,log(TG/HDL-C),LDL-C/HDL-C,HOMA-B and HOMA-IR were calculated respectively. All the patients received the continuous subcutaneous insulin infusion with insulin pump. The treatment continued for more 10~14 days after blood glucose reached the standard. All the above indi-cators were reexamined after treatment. Results Dyslipidemia in patients with newly diagnosed T2DM mainly showed as hypertriglyceridemia and decreased HDL-C compared to the control group(P<0.05). TC/HDL-C,TG/HDL-C,log(TG/HDL-C)and LDL-C/HDL-C significantly increased in these patients(P<0.01). After short-term intensive insulin therapy,all lipid ratios were significantly decreased and the changes of lipid ratios were positively correlated with the change of HOMA-IR(P<0.05). Conclusion Short-term intensive insulin therapy for patients with newly diagnosed type 2 diabetes can significantly lower the lipid ratios related to HDL-C. The effects may be closely related to improvement of insulin resistance.
5.Effect of angiotensin Ⅱ, angiotensin-(1-7) on insulin signaling pathway in NIT-1 cell line
Jiani CHAI ; Mingtong XU ; Shengneng XUE ; Juying TANG ; Lidan JIANG ; Shuang HE ; Yan LI ; Li YAN
Chinese Journal of Endocrinology and Metabolism 2011;27(10):844-848
Objective To evaluate the effect of angiotensin Ⅱ ( Ang Ⅱ ),angiotensin- (1-7) [ Ang- ( 1-7 ) ],and co-action of Ang Ⅱ and Ang-( 1-7 ) on β cell insulin signaling pathway.Methods Mouse pancreatic β cell line NIT-1 was incubated with( 1 )0,10-7,10-6,10-s,10-4 mol/L concentrations of Ang Ⅱ for 24 h ; ( 2 )0,10-7,10-6,10 -5,10-4 mol/L concentrations of Ang- ( 1-7 ) for 24 h; ( 3 ) co-administration of Ang Ⅱ and Ang- ( 1-7 ) was divided into control,10-5mol/L Ang Ⅱ,10-6mol/L Ang-( 1-7 ),10-5mol/L Ang Ⅱ + 10-6mol/L Ang-( 1-7 ) group.Tyrosine phosphorylation of insulin receptor β subunit(IR-β-Tyr) and serine phophorylation of protein kinase B(Akt-Ser) were detected by Western blot.ResultsInsulin-stimulated IR-β-Tyr and Akt-Ser phosphorylation was significantly decreased in Ang Ⅱ 10-5 and 10-4 mol/L group; no significant changes in insulin-stimulated IR-β-Tyr and Akt-Ser phosphorylation were detected between Ang-( 1-7 ) treatment groups and control; Ang-( 1-7 ) blocked the inhibitory effect of Ang Ⅱ on Akt-Ser phosphorylation,yet exerted no effect on Ang Ⅱ-induced IR-β-Tyr phosphorylation inhibition.Conclusion Ang Ⅱ significantly inhibits insulin signaling pathway in β cell; Ang-( 1-7 ) reverts the inhibitory effect of Ang Ⅱ on insulin-stimulated Akt-Ser phosphorylation in β cell.
6.First confirmation of new bunyavirus-infected patients in Zhejiang province and molecular identification of the isolated virus
Lei ZHANG ; Yanjun ZHANG ; Gangqiang DING ; Jie YAN ; Cen FENG ; Juying YAN ; Mifang LIANG
Chinese Journal of Microbiology and Immunology 2011;31(12):1107-1111
ObjectiveTo determine the potential natural foci of new bunyavirus,and isolate and identify the new bunyavirus strain in sera from suspected new bunyavirus-infected patients.MethodsImmunofluorescence assay was used to detect the antigens of new bunyavirus in different tissue specimens of wild rodent animals in Tiantai area of Zhejiang province.Fluorescence quantitative real-time RT-PCR was applied to detect the viral nucleic acid in sera of suspected new bunyavirus-infected patients and the amplification products were analyzed by sequencing.The new bunyavirus in the pateints'sera was isolated using Vero cells.Using nucleocapsid protein encoding gene of new bunyavirus as the target gene,the isolated suspected new bunyavirus strain was identified by RT-PCR and sequencing of the amplification product.Moreover,sequence identity of the amplification product of nucleocapsid protein encoding gene of new bunyavirus was analyzed and compared.ResultsOf the 70 wild rodent animals,5.71% were positive in the immunofluorescence assay.The fluorescence quantitative real-time RT-PCR confirmed that two of the four detected patients'serum specimens were positive.One suspected strain of new bunyavirus was isolated from one pf the two positive patients'serum specimens.The results of RT-PCR and sequencing confirmed that the viral strain exactly belongs to new bunyavirus with 92.2% sequence identity to that of the new bunyavirus isolates in Hubei province but distinct with the new bunyavirus isolates from other areas in China.ConclusionThe presence of natural foci of new bunyavirus and new bunyavirus-infected patients in Zhejiang province are firstly confirmed by this study.There is a geographical diversity of the distribution of new bunyavirus in different groups.
7.Influence of short-term intensive insulin therapy on plasma concentration of lipoprotein-associated phospholipase A2 and secretory phospholipase A2 in newly diagnosed type 2 diabetic patients
Xiuhong LIN ; Mingtong XU ; Lifang MAI ; Juying TANG ; Xiaoyi WANG ; Yan LI ; Li YAN
Chinese Journal of Internal Medicine 2017;56(2):127-129
[Summary] The aim of the study was to explore the effect and its clinical relevance of short -term intensive insulin treatment on plasma concentrations of lipoprotein-associated phospholipase A 2 ( Lp-PLA2 ) and secretory phospholipase A2(sPLA2) in newly diagnosed type 2 diabetes mellitus (T2DM).Ninety newly diagnosed T2DM patients were recruited and received continuous subcutaneous insulin infusion (CSII) for about 2 weeks.After CSII, sPLA2 levels [173.78 (80.95, 278.09) μg/L] were significantly decreased compared with the levels before [219.33 (130.03, 337.30) μg/L], P <0.01, while no statistic significant changes could be viewed in Lp-PLA2 levels.Correlation analysis showed that the changes of Lp-PLA2 and sPLA2 were both positively correlated with the changes of homeostasis model assessment of insulin resistance(HOMA-IR)after CSII (r=0.537,0.493 respectively, all P<0.05).The Lp-PLA2 and sPLA2 level reduction after CSII might help to protect the patients from diabetic macroangiopathy . Trial registration Chinese Clinical Trial Registry , ChiCTR-TRC-10001618.
8.Changes of the first-phase insulin secretion in first-degree relatives of type 2 diabetic subjects with different glucose-tolerance
Li YAN ; Lihong CHEN ; Yang HE ; Juying TANG ; Feng LI ; Xiangru UU ; Hua CHENG
Chinese Journal of Pathophysiology 2000;0(10):-
AIM: To investigate the role of the insulin secretion as well as insulin sensitivity in the onset and development of the type 2 diabetes mellitus (T2DM). METHODS: This study included 38 normal glucose tolerance(NGT) subjects without family history of diabetes, 32 NGT and 36 impaired glucose tolerance(IGT) subjects who were the first-degree relatives of type 2 diabetes, and 35 newly-diagnosed type 2 diabetic patients. ? cell function and insulin sensitivity were examined by using oral glucose-insulin release test (OG-IRT) with SIM reflecting insulin sensitivity and intravenous glucose tolerance test (IVGTT) with AIR3-5 reflecting the first-phase insulin secretion function. AIR3-5 was calculated as the average incremental plasma insulin concentration from the third to the fifth minute after the glucose bolus. AIR3-5 and SIM were compared among the four groups. RESULTS : From NGT, IGT to type 2 diabetes, there was a decreasing tendency of the level of AIR3-5 and SIM, with NGT the highest, IGT the medium and T2DM the lowest. The level of the AIR3-5 in the subjects of NGT who were first - degree relatives of type 2 diabetes were lower than those of NGT without family history of diabetes( P 0.05) . CONCLUSION: Insulin secretion dysfunction may be the primary factor in the onset of type 2 diabetes. Along with the developing of IGT and type 2 diabetes, the insulin secretion and sensitivity decrease.
9.Effects of sevoflurane on Ca2+ transsarcolemmal influx and Ca2+ release function of endoplasmic reticulum in isolated outer hair cells of guinea pigs
Yuantao LI ; Liqiong YANG ; Long ZHOU ; Yan WANG ; Xianghong LUO ; Juying LIU
Chinese Journal of Anesthesiology 2008;28(5):427-429
Objective To investigate the effects of sevoflurane on ca2+ transsarcolemmal influx and ca2+ release function of endoplasmic reticulum in isolated outer hair cells (OHCs) of guinea pigs and the possible mechanism by which sevofhlrane acts on cochleas.Methods The experiment was performed in 2 parts.In experiment I:twelve adult guinea pigs(8 male,4 female)weighing 180-230 g were used.OHCs were mechanically sparated after enzymatic incubation.Thirty OHCs with favorable activity were divided into 3 groups (n=10 each):group I control(C);group Ⅱ low concentration sevoflurane (1.7%,group S1) and group Ⅲ high concentration sevoflurane(3.4%,group S2).The OHCs were stained with 6 umol/L Fluo-3AM in estefified form for 40 min.Group S1 and S2 were pretreated with 1.7% and 3.4% sevoflugsne respectively for 20 min.KCI 40 mmol/L was then added.The intracellular ionized Ca2+ concentration ([C2+]I) was determined byintracelhlar Ca2+ fluorescent intensity using laser scanning confocal microscope.The protocol of the experimentⅡ was the same as the experimentI.The only difference was that caffeine 20 mmol/L was added instead of KCI 40 mmol/L.Results In experiment I:there was no significant difference in baseline[ca2+]I and[ca2+]I after being exposed to sevoflurane among the 3 groups.[Ca2+]I was significanfly increased after addition of KCI as compared with the baseline[Ca2+]I and was significantly lower in group Sl and S2 than in group C and was the lowest in group S2.In experimentⅡ:the[ca2+]I was significantly increased after addition of caffeine but there was no significant difference in[Ca2+]I among the 3 groups.Conclusion Sevoflurane can inhibit voltage-dependent Ca2+ channel opening in a concentration-dependent manner but can not affect ryanodine-sensitive Ca2+ release function of endoplasmic reticuhm in isolated outer hair cells of guinea pigs.
10.Investigation of Circulating Fractalkine and its Receptor CX3CR1 Levels in Patients With Chronic Congestive Heart Failure
Kang YAO ; Shuning ZHANG ; Yan WU ; Hao LU ; Zheyong HUANG ; Juying QIAN ; Yunzeng ZOU ; Junbo GE
Chinese Circulation Journal 2014;(12):992-995
Objective: To observe the changes of circulating fractalkine and its receptor CX3CR1 level in patients with chronic congestive heart failure (CHF).
Methods: Our work included 2 group, CHF group, n=55 patients and Control group, n=25 healthy subjects. Plasma level of soluble fractalkine (sFKN) was measured by ELISA, CX3CR1 in peripheral blood mononuclear cell was examined by lfow cytometry method. The relationship between sFKN and NT-proBNP was studied.
Results: Compared with Control group, CHF group had increased sFKN level, P=0.004, and the patients with NYHY III, IV were more than NYHY II, and CHF group also had the higher CX3CR1 expression (14.7 ± 8.1), P<0.05. The CX3CR1 level increased accordingly with NYHY classiifcation, as the patients with NYHY II, CX3CR1 was at (25.1 ± 12.4), P=0.03 compare with Control group;with NYHY III, CX3CR1 was at (37.3 ± 11.0) , P=0.04 compared with NYHY II;with NYHY IV, CX3CR1 was at (41.7 ± 11.1), P=0.009 compared with NYHY II. The circulating sFKN level was positively related to pro-BNP level (r=0.364, P<0.01).
Conclusion: The circulating FKN l and its receptor CX3CR1 might be involved in pathogenesis of immune-inlfammatory pathogenesis in CHF patients.