57 results on '"Yan GT"'
Search Results
2. Leptin relieves intestinal ischemia/reperfusion injury by promoting ERK1/2 phosphorylation and the NO signaling pathway.
- Author
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Deng ZH Jr, Yan GT, Wang LH, Zhang JY, Xue H, and Zhang K
- Published
- 2012
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3. Dual thyroid ectopia with submental thyroid excision using Sistrunk procedure: A case report.
- Author
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Lim LX, Kwok GT, Wong E, and Morgan GJ
- Abstract
Introduction and Importance: Having two or more sites of simultaneous ectopic thyroid tissue is a rare phenomenon. Thyroid ectopia should be considered in congenital hypothyroidism where no eutopic thyroid gland is found., Case Presentation: This case describes an incidental finding of dual ectopic thyroid tissue on computer tomography scan in an adult with known congenital hypothyroidism that was previously attributed to thyroid agenesis. The decision was made to proceed with a Sistrunk procedure to excise the ectopic submental thyroid as it became more noticeable after weight loss following bariatric surgery, and to monitor the remaining lingual thyroid with a combination of clinical symptomology, imaging and thyroid function studies given its challenging location., Clinical Discussion: The literature on pathophysiology, imaging modalities, and common considerations for surgical extirpation is reviewed., Conclusion: The utility of thyroid scintigraphy may be limited in patients with known thyroid ectopia; other investigative modalities are helpful. The Sistrunk procedure was used to excise an ectopic thyroid, based on its embryological migration from the foramen caecum to the usual pretracheal position along the thyroglossal tract, and is a suitable technique for excision of submental thyroid tissue causing an unsightly mass and where thorough histopathological examination is required to exclude malignancy., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2021
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4. The role of gibberellin synthase gene GhGA2ox1 in upland cotton (Gossypium hirsutum L.) responses to drought and salt stress.
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Shi JB, Wang N, Zhou H, Xu QH, and Yan GT
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- Gene Expression Profiling, Gene Expression Regulation, Plant genetics, Oxidoreductases isolation & purification, Real-Time Polymerase Chain Reaction, Droughts, Gibberellins biosynthesis, Gossypium enzymology, Gossypium genetics, Oxidoreductases genetics, Oxidoreductases metabolism, Salt Stress
- Abstract
Gibberellins (GAs) is one kind of important endogenous hormone in plants that regulates vegetative and reproductive growth of plants. GA2ox is a class of oxidase that plays a regulatory role in the third stage of GAs synthesis. In this paper, we cloned the GhGA2ox1 gene from an upland cotton (Gossypium hirsutum L. var. CCRI49). The results showed that the CDS of GhGA2ox1 is 996 bp, which encode 331 amino acids, which has high homology with GhGA2ox2 and NtGA2ox1. The quantitative real-time PCR showed that under the conditions of salt and drought stress, the expression of GhGA2ox1 had a higher upregulation in root, stem, and leaf of transgenic plant, compared with non-transgenic plant. Cotton plant that overexpressed the GhGA2ox1 gene showed higher drought and salt tolerance than non-transgenic cotton plant, and these results were supported by data of higher free proline, chlorophyll, and relative water content in transgenic plant compared with control plant. The expression level of antiretroviral genes, including GhEREB2, GhDREB1, GhWRKY5, and GhP5CS, was upregulated to varying degrees in transgenic plant. The above results indicate that overexpressed GhGA2ox1 gene can increases the tolerance to respond to drought and salt stress in upland cotton., (© 2019 International Union of Biochemistry and Molecular Biology, Inc.)
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- 2019
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5. [The effects of leptin on neuron apoptosis in mice with cerebral ischemia/reperfusion injury].
- Author
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Si YL, Zhang JY, Deng ZH, Xue H, and Yan GT
- Subjects
- Animals, Brain Ischemia, Caspase 3 metabolism, Infarction, Middle Cerebral Artery, Male, Mice, Proto-Oncogene Proteins c-bcl-2 metabolism, Apoptosis, Leptin pharmacology, Neurons pathology, Reperfusion Injury
- Abstract
Objective: To study the effect of leptin on neuron apoptosis in mice with cerebral ischemia injury., Methods: Seventy-five male Kuming mice were randomly divided into 3 groups:sham, model and leptin intervention group, respectively. Focal cerebral ischemia/reperfusion injury model in mice was established by middle cerebral artery occlusion. Leptin intervention group was injected with leptin (1 μ g/g weight, I. P.) at 0 min of ischemic injury. Neuron apoptosis was detected by TUNEL staining. The mRNA expression of apoptosis relative gene bcl-2 and caspase-3 were detected by RT-PCR. The protein expression of bcl-2 and caspase-3 were detected by immunohistochemistry., Results: In model group, most of the neurons in the central area of cerebral ischemia had necrosis obviously, and the amount of neuron apop-tosis was much higher than that in sham group ( P <0.01). Compared with sham group, both expression of pro-apoptosis gene caspase-3 and anti-apoptosis gene bcl-2 increased significantly in model group ( P <0.01). Compared with model group, the amount of neuron apoptosis and expression level of caspase-3 were decreased significantly ( P <0.01), whereas the mRNA and protein expression of bcl-2 were increased sig-nificantly in leptin intervention group ( P <0.01)., Conclusions: Leptin could reduce neuron apoptosis through down-regulation the expression of caspase-3 and up-regulation the expression of bcl-2. It suggests that leptin could play a neuroprotective role in cerebral ischemia injury.
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- 2016
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6. [The effect of rosuvastatin therapy on CCR2 expression in mononuclear cells and its upstream pathway].
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Du RX, Ye P, Yan GT, Deng ZH, Liang WT, Guo ZK, Zhang HH, and Gen M
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- Cholesterol, LDL blood, Humans, PPAR-beta metabolism, Atherosclerosis drug therapy, Chemokine CCL2 metabolism, Leukocytes, Mononuclear drug effects, Receptors, CCR2 metabolism, Rosuvastatin Calcium pharmacology
- Abstract
Objective: To investigate the effect of rosuvastatin therapy on C-C chemokine receptor(CCR2)expression in mononuclear cells in patients with carotid atherosclerosis and explore the possible upstream mechanism., Methods: Twenty patients without previous statin treatment were enrolled. Rosuvastatin were given 5 to 20 mg/day for 3 months. At baseline and 12 weeks, lipid profile and plasma monocyte chemotactic protein-1 (MCP-1) levels were examined. The mRNA and protein expressions of CCR2 in the mononuclear cells were measured with RT-PCR and flow cytometry, respectively. The mRNA and protein expression of peroxidase proliferator-activated receptor(PPAR β) were detected with RT-PCR and Western blot, respectively., Results: After 3-months rosuvastatin treatment, the patients' low-density lipoprotein cholesterol (LDL-C) levels decreased significantly ( P <0.01). Compared with baseline, the mRNA and protein expressions of CCR2 in the mononuclear cells showed significantly decrease, as well as plasma MCP-1 levels ( P <0.05). Both mRNA and protein expressions of PPAR β in the mononuclear cells increased ( P <0.05)., Conclusions: Rosuvastatin may attenuate MCP-1/CCR2 through PPARβ upstream pathway.
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- 2016
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7. [Effect of repeated hypoxic preconditioning on renal ischemia-reperfusion-induced hepatic dysfunction in rats].
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Yan N, Feng ZG, Yan GT, Yue JH, Zhao YJ, and Geng N
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- Alanine Transaminase blood, Animals, Interleukin-17 blood, Kidney pathology, Kidney Diseases physiopathology, Nitric Oxide blood, Phosphatidylinositol 3-Kinases metabolism, Rats, Rats, Sprague-Dawley, Superoxide Dismutase blood, Tumor Necrosis Factor-alpha blood, Hypoxia, Ischemic Preconditioning, Liver physiopathology, Reperfusion Injury
- Abstract
Objective: To explore the effect of repeated hypoxic preconditioning (RHP) on renal ischemia-reperfusion-induced hepatic dysfunction in rats and the underlying mechanism., Methods: A total of 120 normal SD rats were randomly divided into 4 groups (n=40), namely RHP surgical group, RHP sham-operated (RHPS) group, nonhypoxic surgical group (IRI group), and nonhypoxic sham-operated group (S group). The rats in the hypoxic groups were exposed to hypoxia in a hypoxic chamber for 5 days prior to establishment of renal ischemia-reperfusion model by resection of the right kidney and clamping the left renal hilum. Serum alanine aminotransferase (ALT), IL-17 A, TNF-a, liver superoxide dismutase (SOD) and nitric oxide (NO) were detected at 2, 8 and 24h after reperfusion, and Western blotting was used to determine the expression of p-PI3K and p-AKT;HE staining was used to observe the structural changes in the liver., Results: Compared with IRI group, RHP group showed significantly milder hepatic damage, lower ALT levels and higher NO levels at 2, 8, and 24 after reperfusion (P<0.05); TNF-a levels were lowered at 24 h (P<0.05) and SOD increased at 8 h after the reperfusion (P<0.05). Compared with S group, IRI group and RHP group showed significantly higher IL-17A levels (P<0.05) but without significant difference between the latter two groups (P>0.05). The expressions of p-PI3K and P-Al
- Published
- 2015
8. Serum CRP and urinary trypsin inhibitor implicate postoperative cognitive dysfunction especially in elderly patients.
- Author
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Zhang YH, Guo XH, Zhang QM, Yan GT, and Wang TL
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- Adult, Aged, Aged, 80 and over, Analysis of Variance, Female, Humans, Interleukin-10 blood, Interleukin-6 blood, Male, Matrix Metalloproteinase 9 blood, Mental Status Schedule, Middle Aged, Neuropsychological Tests, Aging blood, C-Reactive Protein metabolism, Cognition Disorders blood, Cognition Disorders etiology, Glycoproteins blood, Postoperative Complications physiopathology
- Abstract
Purpose: Postoperative cognitive dysfunction (POCD) characterized as the decline of memory and executive function after major surgery is not well illustrated. The aim of this study is to discover whether inflammatory cytokines and urinary trypsin inhibitor (uTi) contribute to the development of POCD., Method: Sixty-three patients undergoing lumber discectomy and 47 age-matched control volunteers were involved in this study. The level of C-reaction protein (CRP) and uTi/urine creatinine (Ucr) was measured by immunoturbidimetry and enzyme-inhibition assay, respectively. Meanwhile, ELISA was involved to detect the level of IL-6, IL-10, MMP-9 in serum. Montreal Cognitive Assessment (MoCA) test was used to determine the cognitive decline of the patients and age-matched controls., Result: In POCD group, the level of IL-6, IL-10, CRP, MMP-9 in serum and uTi /Ucr in urine was significantly higher than that in the group without POCD. The POCD was more frequently observed in elderly group than in the middle-aged group (43.75% versus 19.35%, p = 0.038). After logistic regression analysis adjusted by the age, only serum CRP at 72 h postoperation and urinary uTi /Ucr at 24 h postoperation were the independent risk factors of POCD., Conclusion: Age-related increasing proinflammatory postoperation may result in higher occurrence of POCD in the elderly. Additionally, patients with extremely high concentrations of CRP in serum at 72 h postoperation and uTi /Ucr in urine at 24 h postoperation are more likely to experience POCD, especially in the elderly.
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- 2015
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9. Inhibition of the connexin 43 elevation may be involved in the neuroprotective activity of leptin against brain ischemic injury.
- Author
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Deng ZH, Liao J, Zhang JY, Liang C, Song CH, Han M, Wang LH, Xue H, Zhang K, Zabeau L, Tavernier J, and Yan GT
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- Animals, Brain metabolism, Brain Ischemia metabolism, Male, Mice, Neurons metabolism, Receptors, Leptin drug effects, Brain drug effects, Brain Ischemia drug therapy, Connexin 43 metabolism, Leptin pharmacology, MAP Kinase Signaling System drug effects, Neuroprotective Agents pharmacology
- Abstract
Leptin is a multifunctional hormone produced by the ob gene and is secreted by adipocytes that regulate food intake and energy metabolism. Numerous studies demonstrated that leptin is a novel neuroprotective effector, however, the mechanisms are largely unknown. Herein, we demonstrate the protective activities of leptin after ischemic stroke and provide the first evidence for the involvement of the connexin 43 (Cx43) in leptin-mediated neuroprotection. We found that leptin treatment reduces the infarct volume, improves animal behavioral parameters, and inhibits the elevation of Cx43 expression in vivo. In vitro, leptin reverses ischemia-induced SY5Y and U87 cells Cx43 elevation, secreted glutamate levels in medium and SY5Y cell death, these roles could be abolished by leptin receptor blocker. Additionally, leptin administration upregulated the extracellular signal-regulated kinase1/2 (ERK1/2) phosphorylation. Moreover, ERK1/2 inhibitors pretreatment reversed the effects of leptin on Cx43 expression, glutamate levels and cell apoptosis. In conclusion, the present study demonstrated that leptin can reduce the Cx43 expression and cell death both in vivo and in vitro via ERK1/2 signaling pathway. This result provides a novel regulatory signaling pathway of the neuroprotective effects of leptin and may contribute to ischemic brain injury prevention and therapy.
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- 2014
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10. Is leptin a predictive factor in patients with lung cancer?
- Author
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Song CH, Liao J, Deng ZH, Zhang JY, Xue H, Li YM, Liang C, Han M, Zhang K, and Yan GT
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- Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Predictive Value of Tests, RNA, Messenger blood, RNA, Neoplasm blood, Leptin blood, Lung Neoplasms blood, Neoplasm Proteins blood
- Abstract
Objectives: The aim of this study was to evaluate the expression and clinical significance of leptin in lung cancer., Methods: 126 patients with lung cancer ranged from 30 to 83years of age were studied. Serum leptin levels were determined by ELISA. The mRNA and protein levels of leptin in normal and lung cancer tissues were measured by RT-PCR and immunohistochemistry. The relationships between leptin levels and clinicopathological factors were evaluated by Wilcoxon rank sum or Kruskal-Wallis H test., Results: Serum leptin levels in lung cancer patients were significantly higher compared to those in controls and leptin expression in lung cancer tissue was markedly increased than that in normal lung tissue (both P<0.050)., Conclusions: Determination of leptin levels might provide useful predictive information for lung cancer., (Copyright © 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
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11. Localized leptin release may be an important mechanism of curcumin action after acute ischemic injuries.
- Author
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Deng ZH, Liao J, Zhang JY, Hao XH, Liang C, Wang LH, Xue H, Zhang K, and Yan GT
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- Acute Disease, Animals, Disease Models, Animal, Enzyme Inhibitors pharmacology, Epithelial Cells drug effects, Epithelial Cells metabolism, Epithelial Cells pathology, Intestines pathology, Male, Mice, Phosphorylation, Reperfusion Injury pathology, Reperfusion Injury prevention & control, Signal Transduction drug effects, Curcumin pharmacology, Intestines drug effects, Leptin biosynthesis, Reperfusion Injury metabolism
- Abstract
Background: Previous studies have demonstrated that both curcumin and leptin are protective factors against acute injuries. Here, we investigated whether leptin and its signaling pathway mediate the protective effects of curcumin., Methods: A solid dispersion of curcumin-polyvinylpyrrolidone K30 was prepared and administered intraperitoneally. In vivo intestinal ischemia/reperfusion (I/R) injury in mice determined the effects of curcumin administration on inflammation, oxygen radical production, and leptin expression. In vitro studies using the venous epithelial cell line ECV-304 examined hypoxia/reoxygenation-induced leptin expression and release after curcumin administration. Furthermore, the effects on the leptin-regulated ERK1/2 and p38 MAPK signaling pathways were also explored., Results: Intestinal I/R induced marked bowel injuries. Curcumin treatment significantly improved animal survival and reduced the pathologic injuries in the intestines. Furthermore, the elevated intestinal water content and levels of malondialdehyde, interleukin 1β (IL-1β) and IL-6 were significantly decreased, but levels of superoxide dismutase increased. Interestingly, we found that the decreased leptin and its receptor Ob-Rb were restored by curcumin administration. In addition, in vitro studies showed that curcumin increased leptin expression and release after hypoxia/reoxygenation-induced cell injuries. Moreover, curcumin treatment restored decreased ERK1/2 phosphorylation (p-ERK1/2) and inhibited overactive p38 (p-p38) after injuries, and the effect was reversed by a leptin-specific antibody or Ob-R blocker., Conclusion: These data suggest that leptin and Ob-Rb-dependent ERK and p38 MAPK signaling pathways may be involved in curcumin protection against intestinal I/R injury, and leptin may be a potential target of curcumin in intestinal I/R injury and other related acute diseases.
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- 2013
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12. [The effect of leptin on Cx43 expression in protecting mice cerebral ischemia/reperfusion injury].
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Wu QY, Zhang JY, Deng ZH, and Yan GT
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- Animals, Astrocytes pathology, Brain metabolism, Brain pathology, Brain Ischemia metabolism, Brain Ischemia physiopathology, Cell Hypoxia, Cells, Cultured, Male, Mice, Rats, Rats, Sprague-Dawley, Reperfusion Injury metabolism, Connexin 43 metabolism, Leptin pharmacology, Reperfusion Injury prevention & control
- Abstract
Objective: To explore the effect of leptin on expression of Cx43 after rat cerebral ischemia/ reperfusion injury and its related mechanism., Methods: Forty-five male kunming mice were randomly divided into 3 groups: sham group, model group and leptin group. Mouse models of transient focal cerebral ischemia were established by occlusion of the right middle cerebral artery for 2 h followed by 24 h reperfusion in model and leptin group. Mice of leptin group were intraperitoneally injected with 1 mg/kg leptin at 0 minute after ischemia. The infarct volume and neurological deficit scores following leptin treatment were determined using TTC staining and the Longa's score, respectively, to evaluate the protective effect of leptin against ischemic cerebral injury. The histopathological changes in the brain were observed with HE staining. The astrocytes of SD rat cerebral cotex were cultured primaryly and purified, and then divided them into four groups: control, model, leptin 100 microg/L, and leptin 500 microg/L. The cerebral astrocytes with hypoxia/reoxygenation injury were induced. The cellular viability of injury was detected by MTT assay. The effect of leptin on Cx43 expression was detected by Western blot in brain tissues and astrocytes., Results: Compared with the model group, the neurological deficits and cerebral infarct volume of leptin group were reduced (P< 0.05), the histopathological injury in the brain tissues was alleviated and the expression of Cx43 was decreased markedly (P < 0.01). The survival rate of astrocytes was increased significantly in leptin 500 microg/L group (P < 0.01), whereas the Cx43 expression of astrocytes decreased (P < 0.01). But the difference of leptin 100 mcirog/L was not significant (P > 0.05)., Conclusion: Leptin can ameliorate cerebral pathological changes in the event of IR injury by suppressing the expression of Cx43 both in vivo and vitro experiments.
- Published
- 2012
13. Leptin attenuates cerebral ischemia/reperfusion injury partially by CGRP expression.
- Author
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Zhang JY, Yan GT, Liao J, Deng ZH, Xue H, Wang LH, and Zhang K
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- Animals, Apoptosis drug effects, Brain blood supply, Brain drug effects, Brain pathology, Brain physiopathology, Calcitonin Gene-Related Peptide antagonists & inhibitors, Caspase 3 genetics, Cell Hypoxia drug effects, Cerebrovascular Circulation drug effects, Leptin therapeutic use, Male, Mice, Nervous System Diseases complications, Nervous System Diseases drug therapy, Neurons drug effects, Neurons metabolism, Neurons pathology, Neuroprotective Agents therapeutic use, Oxygen metabolism, Proto-Oncogene Proteins c-bcl-2 genetics, RNA, Messenger genetics, RNA, Messenger metabolism, Rats, Regional Blood Flow drug effects, Reperfusion Injury pathology, Reperfusion Injury physiopathology, Up-Regulation drug effects, Brain Ischemia complications, Calcitonin Gene-Related Peptide genetics, Gene Expression Regulation drug effects, Leptin pharmacology, Neuroprotective Agents pharmacology, Reperfusion Injury drug therapy, Reperfusion Injury genetics
- Abstract
Ischemic stroke is a medical emergency triggered by a rapid reduction in blood supply to localized portions of the brain, usually because of thrombosis or embolism, which leads to neuronal dysfunction and death in the affected brain areas. Leptin is generally considered to be a strong and quick stress mediator after injuries. However, whether and how peripherally administered leptin performs neuroprotective potency in cerebral stroke has not been fully investigated. It has been reported that CGRP(8-37), an antagonist of the CGRP receptor, could reverse the protective effect of leptin on rats with CIP (caerulein-induced pancreatitis). However, the question remains: are leptin and CGRP associated in cerebral ischemia/reperfusion injury? The present study attempted to evaluate the relationship between CGRP expression and leptin neuroprotective effects (1mg/kg in 200 μL normal saline, i.p.) on focal cerebral ischemia/reperfusion injury in mice and the protective effect of leptin (500 μg/L) on neurons during hypoxia/reoxygenation injury. Peripheral administration of leptin alleviated injury-evoked brain damage by promoting CGRP expression, improving regional cerebral blood flow, and reducing local infarct volume and neurological deficits. Furthermore, leptin also promoted bcl-2 expression and suppressed caspase-3 in vivo and vitro after injury. Administration of CGRP(8-37) (4 × 10(-8)mol/L) partly abolished the beneficial effects of leptin, and restored the normal expression levels of bcl-2 and caspase-3 in neurons, which indicated that leptin-induced protection of neurons was correlated with release of CGRP. These results indicate that the neuroprotective effect of leptin against cerebral ischemia/reperfusion injury may be strongly relevant to the increase of CGRP expression., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
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14. MicroRNA-193a represses c-kit expression and functions as a methylation-silenced tumor suppressor in acute myeloid leukemia.
- Author
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Gao XN, Lin J, Li YH, Gao L, Wang XR, Wang W, Kang HY, Yan GT, Wang LL, and Yu L
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- Adolescent, Adult, Aged, Antineoplastic Agents pharmacology, Azacitidine pharmacology, Bone Marrow Cells drug effects, Bone Marrow Cells metabolism, Cell Line, Tumor, Cells, Cultured, CpG Islands, Female, Gene Silencing drug effects, Genes, Tumor Suppressor drug effects, Humans, Leukemia, Myeloid, Acute drug therapy, Male, Middle Aged, Monocytes drug effects, Monocytes metabolism, Promoter Regions, Genetic, Proto-Oncogene Mas, Young Adult, DNA Methylation, Leukemia, Myeloid, Acute metabolism, MicroRNAs metabolism, Proto-Oncogene Proteins c-kit biosynthesis
- Abstract
Aberrant activation of c-kit proto-oncogene contributes to abnormal cell proliferation by altering the tyrosine kinase signaling and constitutes a crucial impetus for leukemogenesis. Epigenetic silencing of tumor-suppressive microRNAs (miRNAs) is a key oncogenic mechanism for the activation of oncogenes in tumors. In this study, several miRNAs potentially binding to the 3'-untranslated region of human c-kit mRNA were screened by luciferase reporter assays. Among these miRNAs, miR-193a was embedded in a CpG island and epigenetically repressed by promoter hypermethylation in acute myeloid leukemia (AML) cell lines and primary AML blasts, but not in normal bone marrow cells. Importantly, miR-193a levels were inversely correlated with c-kit levels measured in 9 leukemia cell lines and 27 primary AML samples. Restoring miR-193a expression in AML cells harboring c-kit mutation and/or overexpression, either by synthetic miR-193a transfection or by DNA hypomethylating agent 5-azacytidine (5-aza) treatment, resulted in a significant reduction in c-kit expression at both RNA and protein levels and inhibition of cell growth. The growth-inhibitory activity of miR-193a was associated with apoptosis and granulocytic differentiation. Moreover, 5-aza-induced c-kit reduction could be partially blocked by miR-193a inhibitor, leading to a reversal of antiproliferative and proapoptotic effects of 5-aza. These data reveal a critical role for methylation-repressed miR-193a in myeloid leukemogenesis and the therapeutic promise of upregulating miR-193a expression for c-kit-positive AML.
- Published
- 2011
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15. [The role of Leptin on neuron apoptosis in mice with cerebral ischemia/reperfusion injury].
- Author
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Yan GT, Si YL, Zhang JY, Deng ZH, and Xue H
- Subjects
- Animals, Brain Ischemia metabolism, Caspase 3 metabolism, Male, Mice, Mice, Inbred Strains, Neurons cytology, Neurons metabolism, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-bcl-2, Reperfusion Injury metabolism, Apoptosis drug effects, Brain Ischemia pathology, Leptin pharmacology, Neurons drug effects, Reperfusion Injury pathology
- Abstract
Objective: To study the effect of Leptin on neuron apoptosis in mice with cerebral ischemia injury and its mechanism., Methods: Seventy-five mice were randomly divided into three groups. Focal cerebral ischemia/reperfusion injury model in mice was reproduced by middle cerebral artery occlusion for 2 hours followed by reperfusion. In Leptin intervention group mice were given Leptin 1 μg/g during cerebral ischemia by intraperitoneal injection. Mice in the model group were given equal amount of phosphate buffer saline. After reperfusion for 24 hours, the neuron apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. The mRNA and protein expression of apoptosis relative gene caspase-3 and bcl-2 were determined by reverse transcription-polymerase chain reaction (RT-PCR) and immuno histochemistry., Results: Most of neuron necrosis was observed in cerebral ischemia center in model group. Compared with sham-operation group, neuron apoptosis rate, mRNA and protein expression of caspase-3 and bcl-2 in model group increased significantly [apoptosis rate: (68.65 ± 0.79)% vs. (4.40 ± 0.00)%, caspase-3 mRNA: 2.563 ± 0.250 vs. 0.153 ± 0.020, bcl-2 mRNA: 0.337 ± 0.100 vs. 0.125 ± 0.030, caspase-3 protein (absorbance value, A value): 0.57 ± 0.05 vs. 0.37 ± 0.03, bcl-2 protein (A value): 0.51 ± 0.04 vs. 0.35 ± 0.01, all P<0.01]. The apoptosis rate of penumbra neurons was reduced in Leptin intervention group significantly compared with model group [(42.30 ± 8.45)% vs. (68.65 ± 0.79)%, P<0.01]. Compared with model group, the mRNA and protein expression of caspase-3 in Leptin intervention group were reduced significantly [caspase-3 mRNA: 2.267 ± 0.040 vs. 2.563 ± 0.250, caspase-3 protein (A value): 0.45 ± 0.04 vs. 0.57 ± 0.05, P>0.05 and P<0.01], and the mRNA and protein expression of bcl-2 in Leptin intervention group upregulated significantly [bcl-2 mRNA: 0.662 ± 0.040 vs. 0.337 ± 0.100, bcl-2 protein (A value): 0.76 ± 0.09 vs. 0.51 ± 0.04, both P<0.01]., Conclusion: Leptin could reduce apoptosis of neurons through down-regulation of the expression of caspase-3 and up-regulation of the expression of bcl-2. The results suggest that Leptin plays a neuroprotective role in cerebral ischemia injury.
- Published
- 2011
16. A clinical study on the effects and mechanism of xuebijing injection in severe pneumonia patients.
- Author
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Qi F, Liang ZX, She DY, Yan GT, and Chen LA
- Subjects
- Adult, Aged, Aged, 80 and over, Cytokines immunology, Female, Humans, Male, Middle Aged, Pneumonia immunology, Young Adult, Drugs, Chinese Herbal administration & dosage, Pneumonia drug therapy
- Abstract
Objective: To observe the effects of Xuebijing Injection in patients with severe pneumonia, and to explore the mechanism., Methods: Eighty cases of severe pneumonia are randomly assigned to the Xuebijing treatment (forty cases) and the control group (forty cases), with the same routine therapy provided in both groups. Clinical effective rates, inflammatory factors and organ function were observed in both groups., Results: The effective rate was higher in Xuebijing group than that of the control group (80.0% vs. 67.5%, P < 0.05). As compared with the control group, the LDH, alpha1-AG, alpha1-AT levels and the peak body temperature decreased markedly with the Xuebijing treatment going, and the secretion of TNF-alpha, IL-6, IL-8 was suppressed in Xuebijing group; but no significant difference was found in leptin level., Conclusion: Xuebijing Injection may show a protective effect in patients with severe pneumonia. The mechanism is possibly with the decreased secretion of TNF-alpha, IL-6, and IL-8.
- Published
- 2011
- Full Text
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17. [Effect of inhibition of cytosolic phospholipase A₂ on Leptin release from human umbilical vein endothelial cells induced by lipopolysaccharide].
- Author
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Qi F and Yan GT
- Subjects
- Cells, Cultured, Human Umbilical Vein Endothelial Cells drug effects, Humans, Lipopolysaccharides adverse effects, Umbilical Veins cytology, Human Umbilical Vein Endothelial Cells metabolism, Leptin metabolism, Phospholipases A2, Cytosolic metabolism
- Abstract
Objective: To determine Leptin levels in supernatant fluid of culture of human umbilical vein endothelial cells (ECV-304) after being challenged by lipopolysaccharide (LPS) and calcium ion vector A23187, and to explore the possible relation between Leptin release and cytosolic phospholipase A(2) (cPLA(2)) activity in an inflammatory cell model., Methods: ECV-304 cells were cultured in vitro. Experiment 1: the cells were divided into seven groups: blank control group, LPS 5, 10, 20 μg/ml stimulation groups, A23187 0.1, 1.0, 10.0 μmol/L stimulation groups. The supernatants were collected at 6, 12 and 24 hours.Experiment 2: according to the results of experiment 1, the cells were divided into eight groups: blank control group, LPS 20 μg/ml stimulation group, the inhibitor of cPLA2 AACOCF3 0.1, 1.0, 10.0 μmol/L plus LPS stimulation groups, the inhibitor of mitogen-activated protein/extracellular signal-regulated protein kinase kinase 1/2 (MEK1/2) U0126 0.1, 1.0, 5.0 μmol/L plus LPS stimulation groups, with AACOCF3 or U0126 added 1 hour before the addition of LPS, and the supernatants were collected 24 hours after the addition of LPS. Leptin level was determined by radioimmunoassay., Results: Experiment 1: with increase in LPS concentration and prolongation of time, Leptin release was decreased gradually. After 24 hours of interaction the concentration of Leptin (ng/ml) in LPS 20 μg/ml group was decreased significantly compared with the blank control group (0.540±0.109 vs. 0.823±0.048,P<0.05). However, A23187 had no significant effect on Leptin release. Experiment 2: LPS rendered cells to release less Leptin (ng/ml: 0.558±0.069 vs. 0.825±0.067,P<0.05); by adding AACOCF3 or U0126 in different concentration before adding LPS rendered the cells to release more Leptin (ng/ml), and it showed concentration-dependent (the AACOCF3 0.1, 1.0, 10.0 μmol/L groups were 0.673±0.135, 0.723±0.055, 0.797±0.062, respectively; the U0126 0.1, 1.0, 5.0 μmol/L groups were 0.698±0.112, 0.862±0.184, 0.935±0.145, respectively). The release of Leptin in AACOCF3 1.0 μmol/L, 10.0 μmol/L and U0126 1.0 μmol/L, 5.0 μmol/L groups was significantly higher than LPS 20 μg/ml stimulation group (all P<0.05)., Conclusion: There is a possible relation between Leptin release and cPLA 2 activity in inflammatory cells induced by LPS.
- Published
- 2011
18. Endogenous leptin fluctuates in hepatic ischemia/reperfusion injury and represents a potential therapeutic target.
- Author
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Lin J, Gao XN, Yan GT, Xue H, Hao XH, and Wang LH
- Subjects
- Alanine Transaminase blood, Amine Oxidase (Copper-Containing) blood, Animals, Blood Glucose metabolism, Duodenum metabolism, Duodenum pathology, Liver blood supply, Liver pathology, Lung metabolism, Lung pathology, Male, Models, Animal, Peroxidase blood, Rabbits, Rats, Rats, Sprague-Dawley, Reperfusion Injury pathology, Leptin metabolism, Leptin therapeutic use, Liver metabolism, Reperfusion Injury drug therapy, Reperfusion Injury metabolism
- Abstract
Aim: To evaluate the role of leptin in the internal disorders during hepatic ischemia/reperfusion injury., Methods: A rat model of 70% hepatic ischemia/reperfusion injury was established, with groups of sham-operation (Sham), 60 min ischemia/60 min reperfusion (I60'R60'), I60'R150', I60'R240' and I60'R360'. Serum leptin was detected by a self-produced radioimmunoassay; serum glucose, total anti-oxidation capacity, myeloperoxidase, alanine transaminase and diamine oxidase were determined by relevant kits, while histological alterations and protein levels of leptin in the lung, liver and duodenum were examined by hematoxylin-eosin staining and immunohistochemistry. Spearman's rank correlation between leptin and other variables or grading of tissue impairment were analyzed simultaneously., Results: Serum leptin in I60'R360' was significantly higher than in Sham and I60'R240' groups (both P < 0.05), serum glucose in I60'R360' was higher than in Sham and I60'R150' (both P < 0.05), and serum total anti-oxidation capacity in I60'R240' and I60'R360' were higher than in Sham (both P < 0.05) and I60'R150'groups (both P < 0.01). Serum myeloperoxidase in groups of I60'R240' and I60'R360' were lower than in I60'R150'group (both P < 0.05), serum alanine transaminase in the four reperfusion groups were higher than in the Sham group (all P < 0.05), while serum DAO in I60'R360' was lower than in I60'R60' (P < 0.05). Histological impairment in the lung, liver and duodenum at the early phase of this injury was more serious, but the impairment at the later phase was lessened gradually. Protein levels of leptin in the lung in the four reperfusion groups were significantly lower than in the Sham group (all P < 0.01), decreasing in the order of I60'R150', I60'R60', I60'R360' and I60'R240'; the levels in the liver in I60'R60' and I60'R240' were higher than in the Sham group (both P < 0.01), while the levels in I60'R240' and I60'R360' were lower than in I60'R60' (both P < 0.01); the levels in duodenum in I60'R240' and I60'R360' were higher than in Sham, I60'R60' and I60'R150' (all P < 0.01), while the level in I60'R150' was lower than in I60'R60' (P < 0.05). There was a significantly positive correlation between serum leptin and alanine transaminase (ρ = 0.344, P = 0.021), a significantly negative correlation between the protein level of leptin in the lung and its damage scores (ρ = -0.313, P = 0.036), and a significantly positive correlation between the protein level of leptin in the liver and its damage scores (ρ = 0.297, P = 0.047)., Conclusion: Endogenous leptin fluctuates in hepatic ischemia/reperfusion injury, exerts a potency to rehabilitate the internal disorders and represents a potential target for supportive therapy.
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- 2010
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19. [Preliminary investigation of the changes and mechanism of Leptin after myocardial ischemia/reperfusion injury].
- Author
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Xue H, Yan GT, Lin J, and Hao XH
- Subjects
- Animals, Leptin blood, Male, Myocardial Reperfusion Injury blood, Rats, Rats, Sprague-Dawley, Leptin metabolism, Myocardial Reperfusion Injury metabolism, Myocardium metabolism
- Abstract
Objective: To explore the effect of rat myocardial ischemia/reperfusion (I/R) injury on serum Leptin, endothelin (ET), C-reactive protein (CRP) and myocardial Leptin expression, and discuss the role of Leptin in myocardial I/R injury., Methods: Fifty Sprague-Dawley (SD) rats were randomly divided into sham-operation, ischemia and I/R 1, 2, 3 hours groups, with 10 rats in each group. Anterior descending artery of the left coronary artery was ligated for 45 minutes and released for 1, 2 and 3 hours to establish myocardial I/R model, and the said artery of the rats in sham-operation group was not ligated. Blood from left femoral artery was collected at different time points, and serum Leptin, ET and CRP contents were detected. Myocardial tissue was harvested, and stained with hematoxylin-eosin (HE) and immunohistochemistry for its observation of the myocardial pathological changes and Leptin protein expression., Results: Serum Leptin content (μg/L) of ischemia group was significantly lower than that of sham-operation group (4.69±1.67 vs. 6.48±2.02, P<0.05); as the reperfusion time was prolonged, serum Leptin level increased gradually, and the level of I/R 3-hour group recovered to that before injury [(6.59±2.58) μg/L]. ET content (ng/L) of ischemia group was significantly higher than that of sham-operation group (110.58±37.86 vs. 80.74±34.43, P<0.05), the levels of ET in I/R 1, 2 and 3 hours groups were significantly lower than those of ischemia group (35.87±13.56, 31.98±10.88, 34.56±14.37 vs. 110.58±37.86, all P<0.05). CRP content (mg/L) of ischemia group was significantly higher than that of sham-operation group (13.12±4.82 vs. 3.24±1.72, P<0.01); as the reperfusion time was prolonged, serum CRP level increased gradually, and the levels of I/R 1, 2 and 3 hours groups were significantly higher than those of ischemia group (18.37±6.48, 24.30±9.51, 27.08±8.32 vs. 13.12±4.82, all P<0.05). Pathological examination showed that there was necrosis of ischemic myocardial cells in ischemia group, with mild congestion and edema in interstitial spaces. After I/R injury, the myocardial cells showed coagulative necrosis, and there was severe congestion of myocardial interstitial. Immunohistochemistry results showed that there was a tendency of decrease in Leptin protein expression in the early phase but increase in the late phase after the injury., Conclusion: Leptin content in the serum and myocardial tissue decreases significantly in the early phase after myocardial I/R but increases gradually in the rehabilitative phase, suggesting that Leptin maybe a stress protective factor against I/R-induced myocardial injury. There is a possible association between Leptin and the early increase followed by a delayed decrease of ET as well as the increase of CRP.
- Published
- 2010
20. [Effects of leptin on apoptosis of rat cerebral astrocytes with ischemia/hypoxia injury].
- Author
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Si YL, Zhang JY, Hao XH, Deng ZH, Xue H, and Yan GT
- Subjects
- Animals, Animals, Newborn, Brain pathology, Caspase 3 metabolism, Proto-Oncogene Proteins c-bcl-2 genetics, Proto-Oncogene Proteins c-bcl-2 metabolism, RNA, Messenger genetics, RNA, Messenger metabolism, Rats, Rats, Sprague-Dawley, bcl-2-Associated X Protein genetics, bcl-2-Associated X Protein metabolism, Apoptosis drug effects, Astrocytes pathology, Hypoxia-Ischemia, Brain pathology, Leptin pharmacology, Reperfusion Injury pathology
- Abstract
Objective: To investigate the effect of leptin on apoptosis of rat cerebral astrocytes with ischemia/ hypoxia injury and its mechanism., Methods: The cerebral astrocytes with ischemic/hypoxia injury were induced in neonatal SD rats. The cellular viability of injury of astrocytes was detected by MTT assay. The apoptosis of astrocyte were detected with Annexin V-FITC kit. The effect of leptin on the expression of apoptosis factor bcl-2, bax, caspase-3 was detected by RT-PCR and Western blot., Results: Compared with the ischemia group, the cellular viability of leptin intervention group increased significantly (P < 0.01), while the astrocytes apoptosis of leptin intervention group decreased significantly (P < 0.01). The mRNA and protein expression level of antiapoptosis factor bcl-2 in leptin intervention group was much higher than that of ischemia group (P < 0.01), whereas the mRNA and protein expression of bax and caspase-3 was much lower than that of ischemia group (P < 0.01)., Conclusion: Leptin could significantly decrease the apoptosis of astrocytes with ischemia/hypoxia injury, and it i relevant to the increase of bcl-2 expression and the decrease of bax caspase-3 expression level.
- Published
- 2010
21. Resveratrol derivative, trans-3,5,4'-trimethoxystilbene, exerts antiangiogenic and vascular-disrupting effects in zebrafish through the downregulation of VEGFR2 and cell-cycle modulation.
- Author
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Alex D, Leong EC, Zhang ZJ, Yan GT, Cheng SH, Leong CW, Li ZH, Lam KH, Chan SW, and Lee SM
- Subjects
- Animals, Animals, Genetically Modified, Cell Line, Tumor, Cell Proliferation, Down-Regulation drug effects, Embryo, Nonmammalian cytology, Embryo, Nonmammalian physiology, Endothelial Cells cytology, Humans, Stilbenes chemistry, Transcription, Genetic drug effects, Umbilical Veins cytology, Vascular Endothelial Growth Factor Receptor-2 metabolism, Zebrafish embryology, Zebrafish metabolism, Cell Cycle, Endothelial Cells drug effects, Neovascularization, Physiologic drug effects, Stilbenes pharmacology, Vascular Endothelial Growth Factor Receptor-2 genetics, Zebrafish genetics
- Abstract
Angiogenesis plays an important role in the development of neoplastic diseases such as cancer. Resveratrol and its derivatives exert antiangiogenic effects, but the mechanisms of their actions remain unclear. The aim of this study was to evaluate the antiangiogenic activity of resveratrol and its derivative trans-3,5,4'-trimethoxystilbene in vitro using human umbilical vein endothelial cells (HUVECs) and in vivo using transgenic zebrafish, and to clarify their mechanisms of action in zebrafish by gene expression analysis of the vascular endothelial growth factor (VEGF) receptor (VEGFR2/KDR) and cell-cycle analysis. trans-3,5,4'-Trimethoxystilbene showed significantly more potent antiangiogenic activity than that of resveratrol in both assays. In zebrafish, trans-3,5,4'-trimethoxystilbene caused intersegmental vessel regression and downregulated VEGFR2 mRNA expression. Trans-3,5,4'-trimethoxystilbene also induced G2/M cell-cycle arrest, most specifically in endothelial cells of zebrafish embryos. We propose that the antiangiogenic and vascular-targeting activities of trans-3,5,4'-trimethoxystilbene result from the downregulation of VEGFR2 expression and cell-cycle arrest at G2/M phase., ((c) 2009 Wiley-Liss, Inc.)
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- 2010
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22. [Role of leptin in hepatic ischemia/reperfusion-induced hepatic injury].
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Lin J, Yan GT, Xue H, Hao XH, Zhang K, and Wang LH
- Subjects
- Animals, Leptin genetics, Liver metabolism, Liver pathology, Male, RNA, Messenger genetics, RNA, Messenger metabolism, Random Allocation, Rats, Rats, Sprague-Dawley, Reverse Transcriptase Polymerase Chain Reaction, Leptin metabolism, Liver blood supply, Reperfusion Injury metabolism
- Abstract
Unlabelled: OBJECTIVE; To study the changes of leptin after hepatic ischemia/reperfusion (H-I/R) and its effects on H-I/R-induced hepatic injury., Methods: A 70% H-I/R model of rats was established. The rats were divided into groups with different reperfusion times and sham-operation group. Radioimmunoassay was applied to measure protein levels of leptin in serum and adipose tissues of the rats. Enzyme-colorimetry was used to detect serum alanine transaminase. Hematoxylin-eosin staining and immunohistochemistry were applied to investigate pathological variations and protein expressions of leptin in livers, respectively. RT-PCR was used to detect leptin mRNA expressions in adipose tissues and livers., Results: Compared with the sham-operation group, serum leptin increased significantly in the 60 min ischemia/360 min reperfusion (I60' R360') group; protein level of leptin in adipose tissues increased significantly in the I60'R60' group; serum alanine transaminase increased significantly in all of the four reperfusion groups; protein expressions of leptin in livers increased significantly in the I60'R60' and 160'R240' groups; leptin mRNA expression in adipose tissues decreased significantly in the I60'R150' group; leptin mRNA expression in livers increased significantly in the 160'R60' group; leptin mRNA expressions in livers decreased significantly in the I60'R150', I60'R240' and I60'R360' groups. Pathological investigation showed that hepatic impairments at the early phase of H-I/R were more serious. The impairments at the later phase lessened gradually., Conclusion: The change of leptin expressions after H-I/R may be a protective factor to withstand H-I/ R-induced hepatic injury.
- Published
- 2009
23. Heart-type fatty acid-binding protein is a useful marker for organ dysfunction and leptin alleviates sepsis-induced organ injuries by restraining its tissue levels.
- Author
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Yan GT, Lin J, Hao XH, Xue H, Zhang K, and Wang LH
- Subjects
- Adult, Alanine Transaminase blood, Animals, Biomarkers blood, C-Reactive Protein metabolism, Fatty Acid Binding Protein 3, Fatty Acid-Binding Proteins analysis, Female, Humans, Interleukin-1beta blood, Leptin blood, Male, Mice, Middle Aged, Multiple Organ Failure blood, Multiple Organ Failure physiopathology, Peroxidase blood, Rabbits, Radioimmunoassay, Reproducibility of Results, Sepsis metabolism, Superoxide Dismutase blood, Uric Acid blood, Fatty Acid-Binding Proteins blood, Fatty Acid-Binding Proteins metabolism, Leptin pharmacology, Multiple Organ Failure etiology, Multiple Organ Failure pathology, Sepsis complications
- Abstract
Heart-type fatty acid-binding protein (H-FABP) is widely distributed and has been used to diagnose certain diseases. However, its alteration during infection-evoked organ dysfunction, and the potential association between leptin and it in injury or infection has not been investigated. In the current study, serum H-FABP, leptin, C-reactive protein and interleukin-1beta in the patients with pulmonary infection-induced multiple organ dysfunction were detected. Moreover, a mouse model of sepsis was established, and serum alanine transaminase, uric acid, tissue H-FABP, myeloperoxidase, superoxide dismutase activity and histological alterations in lung and intestine were investigated. Serum H-FABP and leptin increased simultaneously and significantly in the patients, and leptin alleviated pulmonary and intestinal injuries by restraining tissue H-FABP secretions in the mouse model of sepsis. Other investigated variables showed different but independent alterations. In conclusion, H-FABP represents a useful diagnostic marker for organ dysfunction, and its association with leptin will be a novel target for emergency aid.
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- 2009
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24. [Effects of ethyl pyruvate on injuries of sepsis in mice].
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Deng ZH, Ti DD, Xue H, Lin J, Wang LH, and Yan GT
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- Alkaline Phosphatase blood, Animals, Disease Models, Animal, Intestines drug effects, Intestines pathology, Lactic Acid metabolism, Lung drug effects, Lung metabolism, Lung pathology, Male, Mice, Pyruvic Acid metabolism, Sepsis drug therapy, Sepsis metabolism, Uric Acid blood, Pyruvates pharmacology, Sepsis pathology
- Abstract
Objective: To explore the effect of ethyl pyruvate (EP) and alkaline phosphatase (ALP) on injuries of sepsis and the mechanism involved., Methods: A murine sepsis model of cecal ligation and puncture was reproduced, and 90 male Kunming mice were divided randomly into sham-operation, model and EP-intervention groups. 75 mg/kg EP was intraperitoneally injected in EP groups 1 hour after establishment of model, and the mice in model group were given a same volume of Ringer's solution. The eyeballs were removed in the latter two groups, and mice were sacrificed at 15 minutes and 1, 3 and 6 hours in subgroups of 10 mice each. ALP, uric acid (UA) and ratio of lactic acid and pyruvic acid were determined in serum and homogenized lung tissue by autonomous biochemical analyzer, and pathological changes in intestine were observed by hematoxylin-eosin (HE) staining., Results: Compared with sham-operation group, serum ALP in model groups and EP groups decreased significantly (P<0.05 or P<0.01), and ALP level of EP group was significantly lower than model group at 6 hours after injury (P<0.05). Compared with sham-operation group, serum UA in model group increased significantly at 1 hour, and reached the highest level at 3 hours (both P<0.05) but decreased significantly later. UA in EP group was significantly lower than that in model group at 1 hour and 3 hours (both P<0.05). Lactic acid/pyruvic acid ratio in lung homogenate of EP group was significantly lower than that of the model group at all the time points (all P<0.05). Intestinal structural damages were distinctly improved in EP group compared with model group at 3 hours and 6 hours (both P<0.05 )., Conclusion: EP promotes the utilization of serum ALP, decreases serum UA, ameliorates acidosis and intestinal damages, thus exerting a protective effect on sepsis-induced organ injuries.
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- 2009
25. [Changes of leptin levels in serum and myocardium after myocardial ischemia/reperfusion injury].
- Author
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Xue H, Yan GT, Lin J, Hao XH, and Zhang K
- Subjects
- Animals, L-Lactate Dehydrogenase metabolism, Leptin blood, Male, Random Allocation, Rats, Rats, Sprague-Dawley, Leptin metabolism, Myocardial Reperfusion Injury metabolism, Myocardial Reperfusion Injury physiopathology, Myocardium metabolism
- Abstract
Aim: To explore the effect of rat myocardial ischemia/reperfusion injury on leptin levels in serum and myocardium, and discuss the role of leptin in myocardial ischemia/reperfusion injury., Methods: A myocardial ischemia/reperfusion injury model of rats was established, serum lactate dehydrogenase (LDH) and leptin levels were detected, and histopathological changes and leptin expressions in myocardium were investigated by hematoxylin-eosin staining and immunohistochemistry, respectively., Results: Serum LDH of ischemia and reperfusion groups increased significantly (P < 0.05), suggesting the model was successfully established and a certain degree of local myocardial injury was induced. Serum leptin of ischemia group (6.34 +/- 2.49) ng/ml was significantly lower than control group (7.50 +/- 2.93 ng/ml, P <0.05). Leptin levels recovered gradually after reperfusion, reached (8.32 +/- 1.74)ng/ml at 2 h after reperfusion, which recovered to the level before injury (8.38 +/- 2.56) ng/ml, and showed a trend to increase as reperfusion time was elongated. Immunohistochemistry results showed that as compared with sham-operation group, myocardial leptin protein expressions of the other four groups were all significantly lower (P < 0.01), and decreased in order by 45 min ischemia/1 h reperfusion, 45 min ischemia/3 h reperfusion, 45 min ischemia and 45 min ischemia/2 h reperfusion., Conclusion: Leptin level in the blood decreases significantly at the early 45 min after myocardial ischemia/reperfusion injury, and its expression in myocardium also decreases significantly. There may be a certain relationship between the pathological injury of myocardium and the changes of leptin.
- Published
- 2009
26. [Protective effect of leptin against cerebral ischemia/reperfusion injury in mice].
- Author
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Si YL, Zhang JY, and Yan GT
- Subjects
- Animals, Brain drug effects, Brain pathology, Infarction, Middle Cerebral Artery metabolism, Infarction, Middle Cerebral Artery pathology, L-Lactate Dehydrogenase metabolism, Male, Malondialdehyde metabolism, Mice, Nitric Oxide metabolism, Reperfusion Injury metabolism, Reperfusion Injury pathology, Time Factors, Brain Ischemia, Leptin pharmacology, Reperfusion Injury prevention & control
- Abstract
Objective: To investigate the protective effect of leptin against cerebral ischemia/reperfusion injury in mice., Methods: Mouse models of transient focal cerebral ischemia were established by occlusion of the right middle cerebral artery for 2 h followed by 24 h reperfusion. The infarct volume and neurological deficit scores following leptin treatment were determined using TTC staining and the Longa's score, respectively, to evaluate the protective effect of leptin against ischemic cerebral injury. The levels of lactate dehydrogenase (LDH), malondialdehyde (MDA) and nitric oxide (NO) in the brain tissue were measured by colorimetry. The histopathological changes in the brain were observed with HE staining, and the expression of glial fibrillary acidicprotein (GFAP) was detected by immunohistochemistry., Results: Leptin treatment markedly reduced cerebral infarct volume and neurological deficits induced by transient ischemia. The LDH, MDA and NO levels in the brain tissues were significantly decreased after leptin treatment, which also alleviated the histopathological injury, maintained the normal morphology of the astrocytes and increased the expression of GFAP., Conclusion: Leptin produces obvious protective effect against cerebral ischemia/reperfusion injury by inhibiting lipid peroxidation, stabilizing the internal environment and adjusting the activity of the astrocytes.
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- 2009
27. [Distribution of leptin expression and its effect on the recovery of sepsis-induced internal disorders].
- Author
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Lin J, Yan GT, Gao XN, Liao J, Wang LH, and Hao XH
- Subjects
- Animals, Appendix injuries, Intestinal Perforation complications, Leptin blood, Leptin genetics, Ligation adverse effects, Male, RNA, Messenger biosynthesis, RNA, Messenger genetics, Rabbits, Random Allocation, Rats, Rats, Sprague-Dawley, Reverse Transcriptase Polymerase Chain Reaction, Sepsis blood, Sepsis etiology, Gene Expression Profiling, Leptin physiology, Sepsis physiopathology
- Abstract
Objective: To explore the distribution of leptin expression and the effect of sepsis on leptin protein and mRNA levels., Methods: Vital organ samples including hypothalamus, lung, liver, spleen, stomach, duodenum, kidney, epididymal fat pad and testis of normal rats were collected. The mRNA expressions of leptin in those samples were determined by RT-PCR. The sepsis rat model induce by cecal ligation and perforation (CLP) was established, setting groups of sham-operation, CLP model, CLP + intralipid injection, CLP + estradiol injection and CLP + insulin injection, as the latter three groups were set to intervene energy metabolism and neuroendocrine function. Radioimmunoassay was applied to measure serum leptin concentrations in each group at 12 h after injury, while RT-PCR was also used to detect Leptin mRNA expressions in hypothalamus, fat and lung after injury., Results: Leptin mRNA expressions were confirmed in all the above nine vital organs, with the highest in kidney but the lowest in testis. The serum leptin level showed no significant difference between sham operation group and other four groups. Compared with sham operation group, the Leptin mRNA level in CLP group decreased significantly in hypothalamus, fat and lung, while that in the other three groups showed different changes. The effect of intralipid on Leptin mRNA expression was found to be a dual-direction pattern, with central stimulation but peripheral inhibition., Conclusion: Leptin is widely expressed in multiple vital organs, and it may be a protective factor to promote recovery of sepsis-induced internal disorders.
- Published
- 2008
28. [Effect of acute intra-peritoneal infection on leptin expression levels in peripheral blood and vital organs of rats].
- Author
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Lin J, Yan GT, and Wang LH
- Subjects
- Animals, Female, Inflammation metabolism, Intestinal Perforation, Leptin blood, Ligation, Male, RNA, Messenger genetics, RNA, Messenger metabolism, Rabbits, Rats, Rats, Sprague-Dawley, Leptin physiology, Peritonitis metabolism
- Abstract
Aim: To explore the effect of acute intra-peritoneal infection on leptin expression levels in peripheral blood and vital organs, and find out the role leptin plays in acute inflammation., Methods: A cecal ligation and perforation model of rats was established, setting groups of sham-operation, intralipid injection, injury, estradiol injection and insulin injection. A rat leptin radioimmunoassay was used to check serum leptin concentrations at 12 h after the injury, and RT-PCR was also used to detect leptin mRNA expressions in adipose tissue, lung and liver., Results: Compared with serum leptin level of sham-operation group after injury, that of all the other four groups showed no significant difference, while the level of intralipid group was significantly higher than that of injury group and estradiol group. Compared with leptin mRNA expression level of sham-operation group after injury, that of the other four groups had different changes. Leptin mRNA expression of intralipid group was significantly increased in adipose tissue but decreased in lung and liver., Conclusion: Leptin expression levels may be affected by the changes of energy metabolism and neuroendocrine function after injury, which suggests a possible protective role for leptin in the recovery of body homeostasis.
- Published
- 2008
29. Leptin protects vital organ functions after sepsis through recovering tissue myeloperoxidase activity: an anti-inflammatory role resonating with indomethacin.
- Author
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Lin J, Yan GT, Xue H, Hao XH, Zhang K, and Wang LH
- Subjects
- Alanine Transaminase blood, Animals, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Indomethacin pharmacology, Kidney metabolism, Kidney pathology, Liver metabolism, Liver pathology, Lung metabolism, Lung pathology, Mice, Mice, Inbred C57BL, Models, Biological, Neuroimmunomodulation, Sepsis drug therapy, Sepsis pathology, Uric Acid blood, Leptin metabolism, Peroxidase metabolism, Sepsis metabolism
- Abstract
In this research, the role of leptin on sepsis-induced organ dysfunction was evaluated. Making use of a mice sepsis model, changes of alanine transaminase and uric acid in serum, myeloperoxidase activity, leptin levels and histological alterations in heart, lung, liver and kidney were determined. Results showed that sepsis induced significantly higher levels of serum alanine transaminase and uric acid, decreased tissue myeloperoxidase activity and leptin levels, and triggered distinct histological alterations. However, leptin and indomethacin injections reversed those impairments at 6h and/or 12h after injury. These data reveal a protective role of both leptin and indomethacin on vital organ functions after sepsis by recovering tissue myeloperoxidase activity.
- Published
- 2007
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30. [Leptin decreases post-septic pulmonary and intestinal FABP levels and its mechanism].
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Yan GT, Hao XH, Lin J, Xue H, Zhang K, and Wang LH
- Subjects
- Animals, Intestinal Mucosa metabolism, Lung metabolism, Male, Mice, Mice, Inbred Strains, Peroxidase metabolism, Superoxide Dismutase metabolism, Fatty Acid-Binding Proteins metabolism, Leptin pharmacology, Sepsis metabolism
- Abstract
Aim: To detect the effect of sepsis on fatty acid binding proteins (FABP) levels and corresponding enzymes in lung and intestine of mice, and to explore the role for FABP in acute inflammation., Methods: A sepsis model of mice made with cecum deligation and perforation was established, and a radioimmunoassay for FABP and 96-well spectrophotometry assays for myeloperoxidase (MPO) and superoxide dismutase (SOD) which were related with clearance of free radicals,were used to detect their levels in lung and intestine homogenized fluids. Hematoxylin-eosin stain was used simultaneously to check the histopathologic chanes of both tissues., Results: Compared with sham group (108.11 +/- 94.03 and 67.22 +/- 19.47 ng/ml) 6 h and 12 h after sepsis, FABP levels in lung and intestine were significantly higher (204.98 +/- 70.72 and 154.29 +/- 60.14 ng/ml), respectively. Twelve hours after leptin (0.1 mg/kg i p) and indomethacin (2 mg/kg i p) injection, lung FABP level decreased and was lower than septic group (P < 0.05). Moreover, 12 h after sepsis intestinal FABP increased, but it decreased after leptin injection (419.80 +/- 80.06 vs 191.09 +/- 96.75 ng/ml), while indomethacin injection had no such effect. MPO and SOD activities in lung and intestine changed accordingly with time after sepsis, the effect of leptin and indomethacin injections on it had no significant correlation with FABP changes., Conclusion: Leptin can protect vital organ functions such as lung and intestine after sepsis, as FABP levels, the cellular injury marker, were significantly lower than groups without injection. And this effect might have no correlation with the clearance factors of oxygenic free radicals such as MPO and SOD.
- Published
- 2007
31. [p38 MAPK/cPLA2 pathway mediates interleukins release in inflammatory cell model].
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Wang XH, Yan GT, Zhang K, Xue H, Hao XH, and Wang LH
- Subjects
- HeLa Cells, Humans, Lipopolysaccharides pharmacology, Cyclooxygenase 2 metabolism, Interleukin-1beta metabolism, Interleukin-6 metabolism, Phospholipases A2, Cytosolic metabolism, p38 Mitogen-Activated Protein Kinases metabolism
- Abstract
Objective: To explore the underlying mechanism of lipopolysaccharide (LPS)-induced interleukin-1 beta (IL-1 beta) and IL-6 release via p38 mitogen-activated protein kinase (MAPK) pathway in HeLa cells for further identification of involved down-stream message factors., Methods: HeLa cells were challenged with LPS to reproduce inflammatory cell model. The activity or expression of p38 MAPK, cytosolic phospholipase A(2) (cPLA(2)) and COX-2, was inhibited with pretreatment of inflammatory HeLa cells with the inhibitors (SB203580, AACOCF(3), NS-398) or transfected with the cPLA(2) antisense oligonucleotide (SK7111), then the activities and/or expression of p38 MAPK, cPLA(2), COX-2, and relationship with levels of IL-1 beta and IL-6 supernatants were determined in each group., Results: SB203580 obviously down-regulated the activities of p38 and cPLA(2), as well as the release of IL-1 beta and IL-6. AACOCF(3) and SK7111 blocked dose-dependently the activity or expression of cPLA(2), IL-1 beta and IL-6 production. However, the expression of COX-2 could hardly be detected in HeLa cells, even after LPS treatment. At the same time, pre-treatment with NS-398 had no effect on IL-1 beta, IL-6 production., Conclusion: p38 MAPK/cPLA(2) pathway mediates the expression of IL-1 beta and IL-6 resulting from LPS treatment of HeLa cells, while COX-2, as a down-stream enzyme of cPLA(2) has no effect in this process.
- Published
- 2007
32. [Leptin protects sepsis-induced renal injury and research for its mechanism].
- Author
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Yan GT, Xue H, Lin J, Hao XH, Zhang K, and Wang LH
- Subjects
- Animals, Disease Models, Animal, Kidney metabolism, Kidney pathology, Leptin metabolism, Male, Mice, Peroxidase metabolism, Random Allocation, Sepsis metabolism, Sepsis pathology, Superoxide Dismutase metabolism, Uric Acid blood, Kidney physiopathology, Leptin physiology, Sepsis physiopathology
- Abstract
Objective: To detect the effect of sepsis on renal function and corresponding enzymes in mice, and to explore the role of leptin in acute inflammation., Methods: Sepsis was reproduced by cecum ligation and puncture in mice. Serum uric acid (UA) and four enzymes related with synthesis of free radicals in kidney homogenized fluids, myeloperoxidase (MPO), glutathione-S-transferase (GST), xanthine oxidase (XOD) and superoxide dismutase (SOD) were determined with spectrophotometry, and leptin level in kidney was detected by radioimmunoassay. Histopathologic changes in kidney were observed with hematoxylin-eosin staining., Results: Twelve hours after leptin (0.08 mg/kg, i.p.) and indomethacin (8 mg/kg, i.p.) injection, serum UA was significantly decreased [(295.79+/-80.86) micromol/L and (281.78+/-46.35) micromol/L, respectively, vs. sepsis group (474.03+/-75.22) micromol/L]. At the same time, renal leptin levels in leptin injection group [(196.00+/-134.30) microg/g] 12 hours after sepsis and in indomethacin injection group [(169.30+/-132.00) microg/g] 6 hours after sepsis were also significantly higher than sepsis group [(61.65+/-27.29) microg/g]. Six and 12 hours after leptin and indomethacin injection, renal MPO, GST, XOD and SOD activities were affected to certain extent, as the results were not completely inhibited or enhanced. Nevertheless, leptin and indomethacin could promote scavenge and deactivation of free radicals., Conclusion: Low dose leptin can ameliorate sepsis-induced renal injury, which may be related with scavenge and deactivation of free radicals in renal cells, and this mechanism is similar with that of indomethacin.
- Published
- 2006
33. [Changes of IL-2, IL-8, IL-10 and TNF-alpha levels in sera of patients with acute graft-versus-host disease].
- Author
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Wang SH, Da WM, Jin HJ, Jing Y, and Yan GT
- Subjects
- Adolescent, Adult, Female, Hematologic Neoplasms therapy, Humans, Male, Middle Aged, Tumor Necrosis Factor-alpha blood, Graft vs Host Disease blood, Hematopoietic Stem Cell Transplantation adverse effects, Interleukin-10 blood, Interleukin-2 blood, Interleukin-8 blood
- Abstract
The purpose of this study was to explore the roles of cytokines IL-2, TNF-alpha, IL-10 and IL-8 in the pathogenesis of acute graft-versus-host disease after allogeneic hematopoietic stem cell transplantation. The incidence of aGVHD was observed in 33 patients undergoing allogeneic hematopoietic stem cell transplantation. The aGVHD was clinically diagnosed. Sera from the 33 patients were taken before and after allogeneic hematopoietic stem cell transplantation. The IL-2, TNF-alpha, IL-8, IL-10 levels in serum of 33 patients were measured serially by using radioimmuno-assay (RIA). aGVHD occurred in 13 patients including 8 patients with aGVHD I and 5 patients with aGVHD II-IV. The results showed that the circulating levels of IL-2 and TNF-alpha were markedly elevated during aGVHD and strongly correlated with the severity of aGVHD as compared with patients without aGVHD. However, the level of the IL-10 in patients with aGVHD was significantly lower than that in patients without aGVHD. The change of IL-8 level was not significant statistically. It is concluded that IL-2 and TNF-alpha may play important roles in the pathogenesis of aGVHD, and measurement of serum IL-2 and TNF-alpha levels after allo-HSCT can provide predictive indicator for acute GVHD.
- Published
- 2006
34. [Effect of intestinal ischemia/reperfusion injury on protein and mRNA levels of orexin-A].
- Author
-
Lin J, Yan GT, Hao XH, Zhang K, Wang LH, and Xue H
- Subjects
- Animals, Hypothalamus metabolism, Intracellular Signaling Peptides and Proteins genetics, Male, Neuropeptides genetics, Orexins, RNA, Messenger biosynthesis, RNA, Messenger genetics, Random Allocation, Rats, Rats, Sprague-Dawley, Intestines blood supply, Ischemia metabolism, Neuropeptides biosynthesis, Reperfusion Injury metabolism
- Abstract
Objective: To investigate the effect of intestinal ischemia/reperfusion (I/R) injury on orexin-A levels in plasma and hypothalamus, and to find out the role of orexin-A in acute inflammatory responses., Methods: Fifty-four SD rats were randomly divided into a sham-operation group and 5 experiment groups. Then we established the intestinal I/R injury model of rats and setup the 5 experiment groups of 60 min ischemia followed by different periods of time for reperfusion. Protein levels of orexin-A in plasma and hypothalamus were measured by radioimmunoassay, and the changes of orexin-A mRNA expression in hypothalamus were detected by RT-PCR., Results: By analyses on the orexin-A levels in plasma of rats before and after injury, no significant change was observed in the 5 experiment groups (P > 0.05), and the 5 groups' post-injury orexin-A levels in plasma and hypothalamus were not significantly different from the sham-operation group's (P > 0.05). However, by comparison with the sham-operation group after injury, the experiment groups were found to have orexin-A mRNA levels in hypothalamus significantly decreased step by step from 60 min ishchemia/30 min reperfusion (160' R30') to 160'R150'; the lowest level was seen at 160'R150'; and at 160'R240' and I60'R360', the level recovered slowly, but it was still lower than that seen in the sham-operation group., Conclusion: Orexin-A makes a delayed response to intestinal I/R injury and may function as inflammatory cytokine in the metabolic disorders caused by acute inflammation.
- Published
- 2006
35. [Effect of intestinal ischemia/reperfusion injury on leptin and orexin-A levels].
- Author
-
Lin J, Yan GT, Gao XN, Liao J, Hao XH, and Zhang K
- Subjects
- Animals, Female, Inflammation blood, Inflammation genetics, Inflammation physiopathology, Intestine, Small metabolism, Intracellular Signaling Peptides and Proteins genetics, Leptin genetics, Male, Neuropeptides genetics, Orexins, RNA, Messenger biosynthesis, RNA, Messenger genetics, Rabbits, Radioimmunoassay, Rats, Rats, Sprague-Dawley, Reperfusion Injury blood, Reperfusion Injury genetics, Reverse Transcriptase Polymerase Chain Reaction, Intestine, Small blood supply, Intracellular Signaling Peptides and Proteins blood, Leptin blood, Neuropeptides blood, Reperfusion Injury physiopathology
- Abstract
Objective: To explore the effect of intestinal ischemia/reperfusion (I/R) injury on leptin and orexin-A levels in peripheral blood and central secretory tissues, and investigate the roles of leptin and orexin-A in acute inflammatory responses., Methods: An intestinal I/R injury rat model was established, and the rats were grouped according to duration of the reperfusion time following a 60-min ischemia. Radioimmunoassay was used to examine the protein levels of leptin in the serum and adipose tissue, and the protein levels of orexin-A in the plasma and hypothalamus. Reverse transcriptase-polymerase chain reaction was also performed to detect the mRNA expressions of adipose leptin and hypothalamus orexin-A., Results: Compared with that before injury, serum leptin level of 60-min ischemia with 30-min reperfusion (I60'R30') group decreased significantly and that of I60'R360' increased significantly. Compared with the sham-operation group (sham) after injury, serum leptin level of I60'R360' group increased significantly, and adipose leptin protein levels of I60'R30' and I60'R90' groups decreased significantly, whereas that of I60'R360' group increased obviously. Compared with sham group after injury, adipose leptin mRNA expressions of I60'R30', I60'R240' and I60'R360' groups all increased significantly, while that of I60'R150' showed significant decrease. No significant changes were noted in the protein levels of orexin-A either in the plasma or hypothalamus after I/R injury. In comparison with sham group after injury, hypothalamus orexin-A mRNA expressions of I60'R30' and I60'R90' groups showed gradual but significant decrease, and till 150 min of reperfusion, the expression reached its lowest, followed then by slow recovery at 240 and 360 min, though still remaining significantly lower than that of sham group., Conclusion: Leptin and orexin-A have a time-dependent response to intestinal I/R injury, but the former appears to exhibit a faster response, and they may play a certain role in the metabolic disorders of acute inflammation.
- Published
- 2006
36. [Changes in serum leptin levels in patients with surgically induced stress responses].
- Author
-
Yan GT, Hao XH, Xue H, Lin J, Zhang K, and Wang LH
- Subjects
- Adrenocorticotropic Hormone blood, C-Reactive Protein metabolism, Granulocyte Colony-Stimulating Factor blood, Humans, Postoperative Period, Leptin blood, Surgical Procedures, Operative
- Abstract
Objective: To explore the effect of operative trauma induced stress responses on serum leptin levels., Methods: Serum samples of patients who had undergone resection of hepatic tumors or cholecystectomy were collected, and highly sensitive radioimmunoassay and enzyme-linked immunoadsorbent assay (ELISA) were used to determine serum levels of leptin, granulocyte-clone stimulating factor (G-CSF), C-reactive protein (CRP) and adrenocorticotropin hormone (ACTH) in the blood of these patients., Results: Compared with self-control before operation, serum leptin levels decreased slightly right after an abdominal operation (T0), it reached the highest level 1 day after operation (T1), and began to decrease from 2 days (T2) to 4 days after operation (T4), but the level was still higher than that before operation. Serum leptin levels of patients undergoing laparoscopic operation showed no significant difference when compared with that of laparotomy patients. G-SF levels decreased significantly after operation in both groups, and didn't recover to the levels before operation from T1 to T4. CRP levels slightly decreased in both groups at T0, but increased significantly higher than the levels before operation from T1 to T4. ACTH levels of decreased significantly in laparotomy patients from T0 to T1, and began to recover on T2, while that of laparoscopic operation patients showed no significant difference before and after operation., Conclusion: Serum leptin levels of patients increase significantly and constantly subsequent to operative trauma induced stress responses, but this change has no correlation with that of CRP, G-SF and ACTH.
- Published
- 2006
37. Intestinal ischemia-reperfusion injury made leptin decreased.
- Author
-
Shi Y, Yan GT, and Lin J
- Subjects
- Animals, Endothelial Cells cytology, Endothelial Cells metabolism, Intestines blood supply, Male, Models, Biological, Rats, Rats, Sprague-Dawley, Reperfusion Injury blood, Time Factors, Intestines pathology, Leptin metabolism, Reperfusion Injury metabolism
- Abstract
To explore the role and the rule of leptin levels in severe traumatism, an ischemia-reperfusion injury model was established to observe change of leptin levels, and platelet activating factor, noradrenaline, lipopolysaccharide, and endothelin-1 were utilized to induce vascular endothelial cells. Leptin concentrations in serum and supernatant were detected by murine and human leptin radioimmunoassay. The results showed that the first serum leptin level significantly decreased after an injury of 60 min ischemia and 30 min reperfusion versus pre-experimental serum values, and leptin level in serum showed a variational trend to increase as reperfusion time extended; the second, supernatant leptin level significantly decreased after PAF and ET-1 treatments of 6 and 24 h versus the control group. It can be concluded that leptin maybe an inflammatory cytokine to play a protection role in acute inflammation and traumatism.
- Published
- 2006
- Full Text
- View/download PDF
38. [Effect of long tubular bone fracture on serum levels of leptin, acute phase proteins and biochemical markers for organ functions].
- Author
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Lin J, Yan GT, Wang LH, Xue H, Hao XH, and Zhang K
- Subjects
- Adult, Biomarkers blood, C-Reactive Protein metabolism, Female, Fractures, Bone physiopathology, Humans, Interleukin-1 blood, Interleukin-2 blood, Male, Middle Aged, Acute-Phase Proteins metabolism, Fractures, Bone blood, Leptin blood
- Abstract
Objective: To investigate the effect of long tubular bone fracture (LTBF) on serum levels of leptin, acute phase proteins and biochemical markers for organ functions, and to look for the role of leptin in traumatic inflammatory responses., Methods: Serum samples of LTBF patients and normal controls were collected, and immunoassays were used to determine serum levels of leptin and three acute phase proteins, including C-reactive protein (CRP), interleukin-1 (IL-1) and IL-2, and 21 biochemical markers for organ and metabolic functions were measured simultaneously with automatic biochemical analyzer. Correlation between leptin and all the markers was then analyzed., Results: Compared with normal control, serum levels of leptin, CRP, IL-1 and IL-2 increased significantly (all P<0.05), with various degrees of changes in the markers for hepatic, cardiac, renal and metabolic functions. Leptin was independent to all the markers investigated, and it seemed to exert its unique roles., Conclusion: Leptin increases significantly in LTBF-induced acute traumatic inflammatory response, showing a comparatively strong responsiveness to the stimulation, and it may play a role as an anti-inflammatory cytokine.
- Published
- 2006
39. [Correlation analysis of increase in serum level of leptin with that of C reactive protein, troponin T and endothelin in patients with acute myocardial infarction].
- Author
-
Yan GT, Xue H, Lin J, Hao XH, Zhang K, and Wang LH
- Subjects
- Coronary Artery Disease blood, Humans, C-Reactive Protein metabolism, Endothelins blood, Leptin blood, Myocardial Infarction blood, Troponin T blood
- Abstract
Objective: To determine serum leptin levels in patients with acute myocardial infarction (AMI) and coronary atherosclerosis (CS), and to analyze its correlation with C reactive protein (CRP), troponin T (TnT) and endothelin (ET)., Methods: Serum samples from confirmed AMI and CS patients were collected. Leptin and ET were assayed with high sensitive radioimmunoassay, TnT was determined with automatic biochemical analyser, and CRP was determined with enzyme-linked immunosorbant assay (ELISA)., Results: Compared with normal control group, serum leptin, TnT, CRP and ET levels increased significantly (all P<0.01) in AMI patients. Serum levels of other cytokines, except TnT in CS patients, increased significantly compared with normal control group (all P<0.01). Correlation analysis showed that all the changes were not correlated with each other, each being an independent factor. Only serum TnT levels of AMI and CS patients showed a significant difference (P<0.01)., Conclusion: Serum leptin levels of both AMI and CS patients increase significantly without a significant difference between each other, and there is no correlation for leptin with CRP, TnT and ET.
- Published
- 2005
40. [Changes of serum leptin level in pulmonary infection-induced multiple organ dysfunction syndrome].
- Author
-
Yan GT, Xue H, Lin J, Hao XH, Zhang K, and Wang LH
- Subjects
- C-Reactive Protein metabolism, Case-Control Studies, Fatty Acid-Binding Proteins blood, Humans, Interleukin-1beta blood, Multiple Organ Failure etiology, Pneumonia blood, Leptin blood, Multiple Organ Failure blood, Pneumonia complications
- Abstract
Objective: To determine serum levels of leptin and some related cytokines in severely ill patients, including severe pulmonary infection-induced multiple organ dysfunction syndrome (MODS), acute myocardial infarction (AMI) and arrhythmia (AR), and to explore the possible role of leptin in the pathogenesis and diagnosis of MODS., Methods: Radioimmunoassay was used to determine leptin, fatty acid binding protein (FABP), transferrin (Ferr) and interleukin-1beta (IL-1beta), and enzyme-linked immuno adsorbent assay (ELISA) was used to assess C reactive protein (CRP)., Results: Compared with normal individuals, leptin levels in MODS, AMI and AR patients increased significantly (all P<0.01). CRP and IL-1beta levels also increased significantly in MODS, AMI and AR patients, but the changes were more marked (all P<0.05) in MODS patients than in the patients of other two diseases (both P<0.05). Though FABP and Ferr levels of patients in all the three groups of patients showed a trend toward increase, especially in MODS patients, there was no significant difference between them and normal individuals., Conclusion: Serum leptin level increases significantly in pulmonary infection-induced MODS patients with a simultaneous increase of CRP and IL-1beta levels, and the result suggests that leptin plays a possible role in the pathogenesis and prognosis of MODS.
- Published
- 2005
41. [Distribution of Orexin-A mRNA expression in different organs and its variation in acute inflammation].
- Author
-
Yan GT, Lin J, and Liao J
- Subjects
- Animals, Disease Models, Animal, Hypothalamus metabolism, Inflammation metabolism, Intracellular Signaling Peptides and Proteins genetics, Male, Neuropeptides genetics, Orexins, RNA, Messenger metabolism, Random Allocation, Rats, Rats, Sprague-Dawley, Intestines blood supply, Intracellular Signaling Peptides and Proteins metabolism, Neuropeptides metabolism, Reperfusion Injury metabolism, Viscera metabolism
- Abstract
Objective: To explore the distribution of Orexin-A mRNA expression in different organs, and its variation in acute inflammation, and to evaluate the role of Orexin-A in acute inflammatory responses., Methods: Hypothalamus, adipose tissue, lung, stomach, duodenum, liver, spleen and testis of male Sprague-Dawley rats (including normal and those of intestinal ischemia/reperfusion injury model) were harvested, and reverse transcription-polymerase chain reaction(RT-PCR) was used to assess Orexin-A mRNA expression in different tissues of normal rats, and that in the hypothalamus of ischemia/reperfusion injured rats., Results: All tissues expressed Orexin-A mRNA, and it was especially high in the stomach, lung and kidney. After the acute stimulus of ischemia/reperfusion injury, Orexin-A mRNA expression showed a trend of fluctuant declination in the hypothalamus., Conclusion: Orexin-A mRNA is widely expressed in the major organs, and it has a time-dependent response to acute inflammatory stimuli. The results suggest that its expression variation may be used as a novel marker for acute inflammation.
- Published
- 2005
42. Effect of intestinal ischemia-reperfusion injury on protein levels of leptin and orexin-A in peripheral blood and central secretory tissues.
- Author
-
Lin J, Yan GT, Hao XH, Wang LH, Zhang K, and Xue H
- Subjects
- Animals, Antibodies, Enteritis immunology, Enteritis pathology, Intracellular Signaling Peptides and Proteins immunology, Leptin immunology, Male, Neuropeptides immunology, Orexins, Rabbits, Radioimmunoassay, Rats, Rats, Sprague-Dawley, Reperfusion Injury immunology, Adipose Tissue metabolism, Hypothalamus metabolism, Intestines pathology, Intracellular Signaling Peptides and Proteins blood, Leptin blood, Neuropeptides blood, Reperfusion Injury pathology
- Abstract
Aim: To explore the effect of intestinal ischemia-reperfusion injury on protein levels of leptin and orexin-A in peripheral blood and their central secretory tissues and to find out the role leptin and orexin-A play in acute inflammatory responses., Methods: An intestinal ischemia-reperfusion (I/R) injury model of rats was established and rats were divided randomly into six groups: sham-operation group, 60 min ischemia/30 min reperfusion group (I60'R30'), I60'R90', I60'R150', I60'R240' and I60'R360', 9 rats each group. Two highly-sensitive radioimmunoassays for leptin and orexin-A were established and used to check the change of their concentrations in peripheral blood and central secretory tissues before and after intestinal I/R injury., Results: Compared with the serum leptin level before injury, it decreased significantly in I60'R30' group and increased significantly in I60'R360' group; compared to sham-operation group after injury, serum leptin level increased significantly in I60'R360' group; compared to sham-operation group after injury, adipose leptin levels decreased significantly in I60'R30' and I60'R90' groups, while increased significantly in I60'R360' group. There was no significant difference between the expression levels of orexin-A before and after I/R injury., Conclusion: Leptin has a time-dependent response and orexin-A has a delayed response to acute inflammatory stimuli such as intestinal I/R injury and they may participate in metabolic disorders in injury as inflammatory cytokines.
- Published
- 2005
- Full Text
- View/download PDF
43. Leptin fluctuates in intestinal ischemia-reperfusion injury as inflammatory cytokine.
- Author
-
Lin J, Yan GT, Wang LH, Hao XH, Zhang K, and Xue H
- Subjects
- Animals, Anti-Inflammatory Agents, Base Sequence, Cytokines blood, Cytokines genetics, Cytokines metabolism, Inflammation, Leptin blood, Leptin genetics, Male, RNA, Messenger metabolism, Rabbits, Radioimmunoassay, Rats, Sensitivity and Specificity, Adipose Tissue metabolism, Intestines blood supply, Leptin metabolism, Reperfusion Injury metabolism
- Abstract
As leptin is an active mediator mainly secreted by adipose tissue and is closely related with energy metabolism, we evaluate both the changes of leptin levels in serum and adipose tissue with a concise radioimmunoassay and the changes of leptin mRNA expression in adipose tissue with RT-PCR, during the severe metabolic impediment in rat intestinal ischemia-reperfusion (I/R) injury. Results show that not only leptin levels in serum and adipose tissue but also its mRNA expression in adipose tissue undergo a fluctuation according to different injury times. Therefore, we conclude that leptin has a time-dependent response to acute inflammatory stimuli and acts as an anti-inflammatory cytokine.
- Published
- 2004
- Full Text
- View/download PDF
44. [Effect of intestinal ischemia/reperfusion injury on protein and mRNA levels of Leptin in rats].
- Author
-
Lin J, Yan GT, Wang LH, Hao XH, Zhang K, and Xue H
- Subjects
- Adipose Tissue metabolism, Animals, Disease Models, Animal, Female, Intestines blood supply, Leptin blood, Male, RNA, Messenger metabolism, Random Allocation, Rats, Rats, Sprague-Dawley, Reperfusion Injury blood, Leptin metabolism, Reperfusion Injury metabolism
- Abstract
Objective: To investigate the effect of intestinal ischemia/reperfusion injury on Leptin levels in serum and adipose tissue, and evaluate the potential role of Leptin in acute inflammatory response., Methods: An intestinal ischemia/reperfusion injury model of rats was reproduced. Serum and adipose tissue Leptin concentrations and Leptin mRNA expression in adipose tissue were determined by a highly-sensitive murine Leptin radioimmunoassay and reverse transcription-polymerase chain reaction (RT-PCR), respectively., Results: Compared with animals prior to injury, serum Leptin level decreased significantly in ischemia for 60 minutes followed by reperfusion for 30 minutes (I60R30), but it tended to increase in I60R150 and significantly increased in I60R360. Compared with sham group, serum Leptin level tended to increase in I60R240 and elevated significantly in I60R360; Leptin levels in adipose tissue significantly decreased in I60R30 and I60R90, while they increased significantly in I60R360. Compared with sham group, Leptin mRNA levels elevated significantly in I60R30, I60R240 and I60R360, but lowered significantly in I60R150., Conclusion: Leptin has a time-dependent response to acute inflammatory stimuli such as intestinal ischemia/reperfusion injury, and it migh play a role as an inflammatory cytokine.
- Published
- 2004
45. Establishment and primary application of a highly-sensitive orexin-A radioimmunoassay.
- Author
-
Lin J, Yan GT, Hao XH, Zhang K, Wang LH, and Xue H
- Subjects
- Animals, Case-Control Studies, Humans, Hyperlipidemias blood, Hypothalamus chemistry, Intestinal Mucosa blood supply, Intestinal Mucosa pathology, Iodine Radioisotopes, Male, Orexins, Rabbits, Rats, Rats, Sprague-Dawley, Reference Standards, Reperfusion Injury blood, Reproducibility of Results, Sensitivity and Specificity, Carrier Proteins blood, Intracellular Signaling Peptides and Proteins, Neuropeptides blood, Radioimmunoassay methods
- Abstract
Orexin-A was labeled by 125I using the chloramine-T method, and was purified with a Sephadex G-25 chromatographic column. The reaction between antigen and antibody was carried out by a one-step balance method and was incubated at 4 degrees C for 24 hours, then bonded and free antigen were separated by PR reagent. The detection range of this RIA is 21-2000 pg/mL; the lowest detection level is 21 pg/mL. The intra-assay and inter-assay variations were 7.8% and 9.7%, respectively. Plasma orexin-A levels of 30 normal individuals and 30 patients with hyperlipidemia (serum triglyceride > 1.7 mmol/L and serum total cholesterol > 5.7 mmol/L) were detected by this RIA, while orexin-A levels of plasma and hypothalamus in rat intestinal ischemia-reperfusion injury model were also measured. Plasma orexin-A levels of normal individuals was 338.48 +/- 20.24 pg/mL, while those of patients with hyperlipidemia were 343.51 +/- 15.49 pg/mL; there were no significant differences between these two groups t = -0.1976; P = 0.8441. We also found that orexin-A levels of rat plasma and hypothalamus did not express a significant change during the early stages of intestinal ischemia-reperfusion injury. These results have shown that this orexin-A radioimmunoassay is stable, simple, and specific, being sensitive enough to test orexin-A levels in human plasma, rat plasma, and hypothalamus.
- Published
- 2004
- Full Text
- View/download PDF
46. The mediating role of cPLA2 in IL-1 beta and IL-6 release in LPS-induced HeLa cells.
- Author
-
Wang XH, Yan GT, Wang LH, Hao XH, Zhang K, and Xue H
- Subjects
- HeLa Cells, Humans, Oligodeoxyribonucleotides, Antisense pharmacology, Phospholipases A antagonists & inhibitors, Phospholipases A2, Polymerase Chain Reaction, RNA, Messenger biosynthesis, Radioimmunoassay, Interleukin-1 biosynthesis, Interleukin-6 biosynthesis, Lipopolysaccharides pharmacology, Phospholipases A metabolism
- Abstract
Studies were conducted to characterize a HeLa cell model by which the roles of the 85-kDa phospholipase A2 (cPLA2) in interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) release could be evaluated. At first, untreated HeLa cells were compared with lipopolysaccharide (LPS)-treated HeLa cells. The latter resulted in cPLA2 overexpression and an increased trend of IL-1 beta and IL-6 release. The indicated doses of 85-kDa cPLA2 antisense oligonucleotide directed against the initiation site were then used to block cPLA2 in LPS-induced HeLa cells. The process led to a dose-dependent decrease in cPLA2 protein with no noticeable change of cPLA2 mRNA. Compared with that of LPS added only, a reduction of IL-1 beta and IL-6 levels in the supernatants of transfected cells following the repression of cPLA2 was observed. These results suggested that 85-kDa cPLA2 may mediate the signalling cascades by which IL-1 beta and IL-6 were released in LPS-induced HeLa cells., (Copyright 2003 John Wiley & Sons, Ltd.)
- Published
- 2004
- Full Text
- View/download PDF
47. [Primary research of the effect of intestinal ischemia/reperfusion injury on Leptin concentrations].
- Author
-
Lin J, Yan GT, Hao XH, Zhang K, Wang LH, and Xue H
- Subjects
- Animals, Female, Male, Rabbits, Radioimmunoassay, Rats, Rats, Sprague-Dawley, Intestines blood supply, Ischemia blood, Leptin blood, Reperfusion Injury blood
- Abstract
Objective: To explore the effect of intestinal ischemia/reperfusion injury on Leptin concentrations in serum and adipose tissue, and to find out the role of Leptin in acute inflammatory responses., Methods: An intestinal ischemia-reperfusion injury model of rats was established, and used a highly-sensitive murine Leptin radioimmunoassay to check the change of Leptin concentrations in serum and adipose tissue., Results: Serum Leptin level (10.82+/-0.83) microg/L significantly decreased after an injury of 60-minute ischemia and 30-minute reperfusion versus pre-experimental serum levels (16.46+/-3.21) microg/L; Leptin level in serum was higher than that in adipose tissue (4.466+/-2.63) mg/100g, and they both showed a similar changeable trend to increase step by step as reperfusion time extended (P=0.047)., Conclusion: Leptin may be an inflammatory cytokine and may play a role in inflammatory responses such as intestinal ischemia/reperfusion.
- Published
- 2003
48. [Function of eukaryotic transcription factor NF-kappaB in the signal transduction of acute inflammatory response].
- Author
-
Lin J and Yan GT
- Subjects
- Humans, Inflammation metabolism, NF-kappa B metabolism, Signal Transduction
- Published
- 2003
49. Interleukin-1beta expression and phospholipase A(2) activation after intestinal ischemia/reperfusion injury.
- Author
-
Yan GT, Hao XH, Xue H, Wang LH, Li YL, and Shi LP
- Subjects
- Animals, Female, Gene Expression, Interleukin-1 biosynthesis, Male, Phospholipases A biosynthesis, RNA, Messenger biosynthesis, Rats, Rats, Wistar, Interleukin-1 metabolism, Intestines blood supply, Ischemia metabolism, Phospholipases A metabolism, Reperfusion Injury metabolism
- Abstract
The experiments were carried out to explore the interactions between IL-1 beta gene expression, protein level and phospholipase A(2) PLA(2) inhibition after intestinal ischemia/reperfusion injury. Using a rat intestinal ischemia/reperfusion injury model, after collecting the serum, lung lavage, abdomen cavity lavage and important organ tissue samples from control, injury and PLA(2) inhibitor treated groups, IL-1 beta level was measured by radioimmunoassay, and the mRNA expression of IL-1 beta and type II PLA (2)was determined by RT-PCR. After 6 h of injury, the IL-1 beta level in serum was significantly higher than that in the control group; an increase in IL-1 beta was also observed in abdomen cavity lavage 1 or 3 h after injury. IL-1 beta was significantly increased in liver tissue after injury, but was not changed obviously in the lung, kidney and intestinal tissues. IL-1 beta in the lung lavage was significantly higher than that of control group. The mRNA expression of IL-1 beta in lung tissue was increased after injury, but type II PLA(2) mRNA expression was decreased. There were different changes in IL-1 beta level and gene expression after treatment with PLA(2) inhibitor chloroquine, cyclo-oxidase inhibitor indomethacin, or PAF receptor antagonist SR27417 respectively after injury. All these results indicate that after intestinal ischemia/reperfusion injury, the IL-1 beta level and mRNA gene expression are significantly increased, however, the relationship among IL-1 beta, PLA(2) activation and its metabolite release remains to be further elucidated.
- Published
- 2002
50. Establishment of a highly sensitive leptin radioimmunoassay and detection of increased leptin levels in hyperlipidemia and pregnancy.
- Author
-
Yan GT, Hao XH, Xue H, and Lu YP
- Subjects
- Adolescent, Adult, Age Factors, Aged, Animals, Body Weight, Case-Control Studies, Circadian Rhythm, Female, Humans, Hyperlipidemias blood, Immune Sera, Infant, Newborn, Leptin immunology, Male, Middle Aged, Obesity blood, Rabbits, Radioimmunoassay methods, Reproducibility of Results, Sensitivity and Specificity, Hyperlipidemias diagnosis, Leptin blood, Pregnancy, Radioimmunoassay standards
- Abstract
The highly effective antibody has been obtained by immunizing rabbits with recombinant leptin many times. The leptin is iodinated with the chloramine-T method and purified with a Sephadex-G25 chromatography column. The reaction between antigen and antibody is carried out by a one-step balance method and cultured at 4 degrees C for 24 h; the binding and free antigen was then separated by PR reagent. The determining range of this method is about 0.5-24 ng/mL; limited detection level is 0.45 ng/mL, relative standard deviation in a group, and among groups, are less than 5.4% and 8%, respectively. The level of blood leptin in 277 samples of normal persons, in 112 samples of overweight persons (weight/hieght m2 > or = 25) and 224 samples of hyperlipidemic patients have been measured by this method. It is demonstrated that the level of blood leptin in males is much lower than that of the females, and becomes elevated with increased age. Serum leptin level in overweight persons and hyperlipidemic patients is also much higher than that of normal groups (P < 0.01). Serum leptin of 21 workers in our lab at 8:00 AM and 4:00 PM has been tested. It was found that there are no differences between the two time points. The same results are obtained within age groups. Leptin levels of pregnant women's serum is higher than those of the control group (P < 0.001). Leptin in newborn's serum is significantly lower than those of mothers (P < 0.01). There is no obvious correlation between leptin level of mother and newborns by correlation analysis (r = 0.19, P > 0.05). The body weight and body weight index of pregnant women are well correlated with their serum leptin levels (r = 0.33 and 0.35, P < 0.05). The body weight and body weight index of newborns are well correlated with their serum leptin levels (r = 0.54 and 0.49, P < 0.001). The serum leptin level of pregnant women is not correlated with newborn's body weight (r = 0.10). These results have shown that the proposed method is stable, simple, and specific, being sensitive enough to determine leptin levels in human serum or plasma.
- Published
- 2002
- Full Text
- View/download PDF
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