1.Pioglitazone reverses TNF-α-induced insulin resistance in 3T3-L1 adipocytes
Tianshu ZENG ; Lulu CHEN ; Li YUAN
Chinese Journal of Diabetes 2005;13(6):423-425
Objective To investigate whether the effect of pioglitazone on TNF-α-induced insulin resistance is associated with altering IRS-1-induced signaling. Methods 3T3-L1 adipocytes were treated with TNF-α for 24 hours with or without being pretreated with 10μM piglitazone for 6 hours or with pioglitazone alone.Insulin-stimulated glucose uptake of 3T3 adipocytes was measured by using 2-deoxy 3H glucose.The Western blot was used to measure IRS-1, PKB, PKC-λ protein and tyrosine phosphorylation on IRS-1, PKB and PKC-λ phosphorylation. Results Both TNF-α and pioglitazone increased glucose uptake of 3T3 adipocytes under basal status.On TNF-α treated cells, insulin-stimulated glucose uptake was decreased by about 50%, accompanied with the reductions of IRS-1 protein level, tyrosine-phosphorylation of IRS-1 and PKB phosphorylation.TNF-α treatment had no effect on PKC-λ phosphorylation. Pioglitazone pretreatment was able to antagonize TNF-α-induced insulin resistance in 3T3 adipocytes partly reverse IRS-1 protein, increase insulin-stimulated tyrosine phosphorylation of IRS-1,and increase phosphorylations of PKB and PKCλ. Conclusion TNF-α-induced insulin resistance in 3T3-L1 adipocytes is related to impaired tyrosine phosphorylation of IRS-1. Pioglitazone antagonizes the above TNF-α induced insulin resistance.
2.Effect of estrogen on secretion function and the number of pancreatic islet beta cell in ovariectomized rats
Wenfang XIA ; Lulu CHEN ; Tianshu ZENG
Chinese Journal of Geriatrics 2009;28(10):860-864
Objective To investigate the effect of ovariectomy and estrogen on secretion function and number of pancreatic islet beta cell in low-dose streptozotocin-induced diabetic rats. Methods Thirty female SD rats were randomly divided into five groups: normal control(NC) group, streptozotocin(STZ) group, ovariectomized(OVX) group, OVX + STZ(OS) group and OVX+STZ+estradiol(OSE) group. OVX, OS and OSE groups underwent ovariectomy, while NC and STZ groups underwent just sham operation. After surgery, OSE group was treated subcutaneously with estradiol 0.2 mg/kg twice weekly. At the end of 3 weeks, STZ, OS and OSE groups were induced by a single intraperitoneal injection of 40 mg/kg STZ. Then eight days later, plasma glucose and insulin levels were tested. The insulin protein, the average beta cell area and the relative beta cell mass were tested by streptavidin peroxidase conjugation method (SP). The quantification of beta cell apoptosis was performed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). The expressions of proliferating cell nuclear antigen(PCNA) protein, Bax and Bcl-2 were tested. Results With the administration of low-dose STZ, the plasma glucose was significantly higher and the insulin secretion curve after glucose loading, △I30/△G30 and modified beta cell function index(MBCI) were lower in OVX group than in other groups(all P<0.05). At the same time, the insulin protein, the relative beta cell mass and the beta cell area were dramatically decreased(all P<0.05). The beta cell apoptotic index was increased (t = 2.957, P< 0.05), the expression ratio of Bcl-2/Bax was decreased (0.41±0.03 vs. 0.76±0.05, P<0.05). Estrogen replacement therapy could obviously inhibit these changes. Compared with OS group, glucose disturbances and insulin secretion were improved dramatically in OSE group(all P<0.05); the insulin content, the relative beta cell mass and the average beta cell area were all enhanced (all P<0.05); the beta cell apoptotic rate was decreased(t =2.482, P<0.05), and the expression tatio of Bcl-2/Bax was increased (0.71±0.05 vs. 0.41±0.03, P<0.05). Conclusions The ovx rats are significantly more susceptible to low-dose STZ toxicity than in control rats. Under the effect of STZ, the ability of insulin secretion of beta cell is obviously decreased, while apoptosis is increased, which induces a higher glucose level and a lower insulin secretion. Administration of estrogen may protect OVX rats from the metabolic disturbances.
3.Simultaneous Determination of Triamcinolone Acetonide Acetate and Chloramphenicol in Chloramphenicol and Triamcinolone Acetonide Acetate Cream by HPLC-DAD
Ping YANG ; Weixin ZENG ; Lulu SUN
China Pharmacist 2016;19(3):591-593
Objective:To establish an HPLC method for the simultaneous determination of triamcinolone acetonide acetonide ( TAA) and chloramphenicol in the cream. Methods:The chromatographic system consisted of a ZORBAX SB-C18 column (250 mm × 4. 6 mm, 5μm). The mobile phase consisted of methanol and phosphate buffer with gradient elution at a flow rate of 1. 0 ml·min-1, the detection wavelength was 240nm, the column temperature was ambient, and the sample size was 20 μl. Results:The calibration curve was linear for TAA and chloramphenicol within the concentration range of 6. 12-48. 96 μg·ml-1 and 62. 1-745. 2 μg·ml-1 with the recovery of 99. 7% (RSD=1. 3%, n=9) and 99. 4%(RSD=1. 0%, n=9), respectively. Conclusion: The method is sensitive, accurate and specific, and can be used to control the quality of chloramphenicol and triamcinolone acetonide acetate cream.
4.Determination of Chloramphenicol Vaginal Tablets by HPLC
Zhengyuan SHI ; Weixin ZENG ; Lulu SUN
China Pharmacist 2014;(10):1788-1789
Objective:To establish an HPLC method for the determination of chloramphenicol in chloramphenicol vaginal tablets. Methods:An Agilent ZORBAX SB-C18 column (150 mm × 4. 6 mm,5 μm)was used. The mobile phase was composed of 0. 1% sodi-um 1-heptanesulfonate solution-methanol (68∶32),the flow rate was 1. 0 ml·min-1, the UV detection wavelength was 277 nm,the column temperature was 35℃,and the injection volume was 10 μl. Results:The linear range of chloramphenicol was 25. 6-512. 0 μg ·ml-1(r=0. 999 9). The mean recovery was 99. 4%, and RSD was 0. 8%(n=9). Conclusion:The method is simple,accurate and reproducible,and can be used in the determination of chloramphenicol vaginal tablets.
5.TNF-? impairs glucose uptake and IRS-1 associated signaling pathway by stimulated insulin in 3T3-L1 adipocytes
Tianshu ZENG ; Li YUAN ; Lulu CHEN
Chinese Journal of Immunology 2000;0(09):-
Objective:To investigate glucose uptake and IRS-1-associated signaling pathway by stimulated insulin under TNF-? treatment.Methods:3T3-L1 adipocytes were treated with TNF-? within 6 hours and 24 hours respectively. 2-deoxy ~3H glucose was used to measure glucose uptake and western blot was used to measure IRS-1, PKB protein, tyrosine and serine307 phosphorylation on IRS-1, and PKB phosphorylation.Results:On basal status, glucose uptake of 3T3-L1 cells and phospho-tyrosine of IRS-1, PKB phosphorylation, and serine307 phosphorylation on IRS-1 were all low. Insulin stimulation induced glucose uptake and IRS-1 tyrosine phosphorylation, serine307 phosphorylation, PKB phosphorylation rapidly. TNF-? inhibited insulin-induced glucose uptake, tyrosine phosphorylation of IRS-1 and PKB phosphorylation. Rapamycin reversed the effects of TNF-?. Treated with TNF-? within 6 hours increased serine307 phosphorylation but had no effect on IRS-1 protein level. TNF-?-induced serine307 phosphorylation of IRS-1 was not affected by rapamycin. IRS-1 level was decreased under 24 hours TNF-? treatment and rapamycin can reverse the effect.Conclusion:TNF-? induced insulin resistance in 3T3-L1 adipocytes mightbe related to impaired IRS-1 tyrosine phosphorylation, rapamycin could reverse the effects of TNF-?. Treated with TNF-? within 6 hours stimulate phosphrylation of serine307 of IRS-1 and 24 hours treatment decreased IRS-1 protein level. Rapamycin antagonist TNF-?-induced loses of IRS-1.
6.Establishment of Determination Method for Drug Release of Phencynonate Hydrochloride Extended Release Tablets
Zeng YUAN ; Zheng LULU ; Liu HUI
China Pharmacist 2015;(1):11-13,17
Objective:To establish the drug release determination conditions and method for phencynonate hydrochloride extended release tablets. Methods:The drug release of the tablets was determined by HPLC using a Diamonsil C18 (250 mm × 4. 6 mm, 5 μm) column with the mobile phase of acetonitrile-water-phosphoric acid-triethylamine (270∶400∶1. 3∶2), the detection wavelength was 220 nm, the flow rate was 1. 0 ml·min-1 , the column temperature was 30 ℃ and the injection volume was 20 μl. The effects of different release apparatus, release media and rotation speeds on the release of phencynonate hydrochloride extended-release tablets were studied as well. Results:The established drug release determination method had a good linear relationship within the range of 0. 3-5. 0 μg· ml-1(r=0. 999 8), and the average recovery was 100. 6%(RSD=1. 16%, n=15). Under the conditions of 900ml pH 3. 0 phos-phate buffer solution as the release medium, rotation speed of 50 r·min-1 and the settlement basket as the apparatus, the release be-havior of the product was complied with a zero-level model in vitro, and the release equation was as follows:Q=6. 141 2t-9. 328 7(r=0. 996). Conclusion:The method is simple, accurate and reliable, and suitable for the quality control of phencynonate hydrochlo-ride extended-release tablets.
7.Simultaneous Determination of Neomycin Sulfate and Hydrochloric Dyclonine in Compound Twain Oint-ments by HPLC-DAD-ELSD
Songleng DUAN ; Weixin ZENG ; Lulu SUN
China Pharmacist 2015;(5):867-869
Objective:To establish an HPLC-DAD-ELSD method for the simultaneous determination of neomycin sulfate and hy-drochloric dyclonine in compound Twaln ointments. Methods:The assay was performed on an Agilent ZOR BAXSB-C18 column(250 mm × 4. 6 mm, 5μm) with acetonitrile-water as the mobile phase with gradient elution at a flow rate of 1. 0 ml·min-1 . The detection wavelength of DAD was 282 nm. The evaporator temperature of ELSD was set at 50℃ and the nebulizer temperature was set at 60℃with the gas flow rate of 1. 6 L·min-1 . The column temperature was kept at 35℃. Results:The linear range of neomycin sulfate was 141. 54-323. 52 μg·mL-1(r=0. 999 6) with the average recovery of 98. 87%(RSD=0. 95%, n=9). The linear range of hydro-chloric dyclonine was 28. 00-64. 00 μg·mL-1(r=0. 999 6) with the average recovery of 99. 57%(RSD=1. 10%, n=9). Conclu-sion:The method is accurate, sensitive and reproducible, and under the same chromatographic conditions, the determination of all the active ingredients in compound Twaln ointments is achieved, which provides basis for the quality control.
8.Innovative practice of project-based learning and 3 D printing in Computer-aided medicine
Lulu GONG ; Weikang ZENG ; Yunpeng LI ; Zhenghai ZHANG ; Cichen ZHANG
Chinese Journal of Medical Library and Information Science 2017;26(2):67-70
After the application of project-based learning (PBL) and 3D printing in classroom and teaching, the integrating methods and principles of PBL and 3D printing and recent teaching resources were summarized, PBL-based 3D modeling combined with recent innovative practice of 3D printing teaching model, with the course of Computer-aided medicine as an example, showed that the new teaching mode can effectively stimulate the interests of students, and cultivate their innovative thinking.
9.The correlation between human leukocyte antigens-A, B, DRB1 high-resolution alleles and chronic renal failure caused by immunoglobulin-a nephropathy
Lixin YU ; Mingxing ZENG ; Guirong YE ; Min LUO ; Lulu XIAO
Chinese Journal of Organ Transplantation 2015;36(2):73-77
Objective To investigate the correlation between human leukocyte antigens-A,-B,-DRB1 (HLA-A,-B,-DRB1) high resolution alleles and chronic renal failure (CRF) caused by immunoglobulin-a nephropathy (IgAN).Method The polymerase chain reaction-sequence-based typing (PCR-SBT) method was used to investigate the genotypes of HLA-A,-B and-DRB1 high-resolution alleles in 191 cases of CRF caused by IgAN (experimental group) and 503 healthy blood donors (control group).The alleles frequencies between two groups were compared and the association between CRF caused by IgAN and the polyrnorphism of HLA was analyzed.Result (1) There were 25 alleles at A locus,48 alleles at B locus and 32 alleles at DRB1 locus in experimental group.(2) The genetic frequency of HLAA * 2901 [Pc =0.033,OR =10.738,95% CI (1.193,96.691)],HLA DRB1 * 1106 [Pc =0.0001,OR =0.969,95% CI (0.944,0.994)],HLA-DRB1 * 1202[Pc =0.002,OR =1.859,95% CI (1.259,2.745)],HLA-DRB1 * 1401 [Pc =0.021,OR =0.984,95% CI (0.967,0.998)],HLA-DRB1 * 1602[Pc=0.015,OR=1.915,95% CI (1.157,3.17)] in experimental group was higher than in control group (P<0.05).Conclusion There is susceptibility association of HLA-A * 2901,HLA-DRB1 * 1106,HLA-DRE * 1202,HLA-DRB1 * 1401,HLA-DRB1 * 1602 with CRF caused by IgAN.It is concluded that there is a close genetic and immunological correlation between HLA alleles and the pathogenesis of CRF caused by IgAN.
10.Pulmonary phaeohyphomycosis due to Exophiala jeanselmei:a case report and review of literature
Feng YE ; Lulu WU ; Danhong SU ; Qingsi ZENG ; Rongchang CHEN
Chinese Journal of Infection and Chemotherapy 2014;(3):229-234
Objective To better understanding the clinical presentations of phaeohyphomycosis,and improve the diagnosis and management of the disease.Methods We reported a case of pulmonary phaeohyphomycosis caused by Exophiala jeanselmei at the First Affiliated Hospital of Guangzhou Medical University in 2008,and reviewed the relevant literature.The clinical,radio-logical and etiological features were summarized based on this case and the other 23 phaeohyphomycosis patients reported in China from January 1995 to August 2013.Results 24 Chinese cases of phaeohyphomycosis have been reported to date,including 15 males and 9 females.The age of these patients ranged from 4 to 76 (mean 40.0±21 .8)years old.Seventeen patients were otherwise healthy.The other 7 patients had complications.Clinical presentations of phaeohyphomycosis vary widely,including cutaneous and subcutaneous infection in 18 cases,pulmonary and central nervous system involvement in two cases each,para-nasal sinus and palpebral conjunctiva infection one case each.The diagnosis of 18 cases were confirmed both microbiologically and histologically.One case was confirmed histologically alone.Five cases were identified microbiologically alone.The samples for culture were collected from skin abscess (1/5 ),pulmonary tissue (2/5 ),and cervical spinal fluid (2/5 ),respectively. Twenty-two strains of causative organisms were identified,7 of which were Exophiala jeanselmei .Twenty-three patients received treatment.They were cured by antifungal agents alone (18)or in conjunction with surgical resection (4 ),or assisted with XD-635AB-based photodynamic laser therapy (1).Specifically,10 pa-tients were cured by itraconazole alone.Conclusions In China, most patients of phaeohyphomycosis have concurrent conditions or have previously received immunosuppressive agents and cor-ticosteroids.Cutaneous and subcutaneous infection were most common,located mainly on limbs,face,chest and abdominal skin.The most frequently isolated pathogen is Exophiala jeanselmei ,followed by Phialophora verrucosa and Exophiala spinifera .Itraconazole therapy would be very effective.Susceptibility testing is very useful in case of refractory infection.