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Publications (12)21.09 Total impact

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    ABSTRACT: To explore the protective effects of astragaloside IV on retinal ganglion cells (RGC) incubated under high glucose. Cultured RGC-5 were divided into 3 groups: control, high glucose and high glucose+astragaloside IV. The survival rate of cell was measured by CCK-8 kit and flow cytometry. The changes of mitochondrial membrane potential were monitored by confocal laser scanning microscopy while those of RGC-5 mitochondria observed by electron microscopy. When the cell survival rate was 100% in the control group, the survival rate improved after 1 h 5, 10, 50, 100, 200 µg/ml astragaloside IV pretreatment and high-glucose culture. The cell survival rates for 100 mg/L, 200 mg/L of astragaloside IV were 81.6%, 80.0%, the difference from the high glucose group (66%) was significant (P < 0.05) and 100 mg/L of astragaloside IV was the best protection concentration. The apoptotic rate for 100 mg/L astragaloside IV pretreated group of RGC-5 cell was 6.1%. And it could partially inhibit the RGC-5 cell apoptosis caused by high glucose (8.2%) (P < 0.05). In the high-glucose group, the cells showed marked increases in mitochondrial swelling, especially for cristae. Numerous normal mitochondria were observed in 100 mg/L astragaloside IV pretreated group. Astragaloside IV could elevate mitochondrial membrane potential and alleviate mitochondrial swelling. Astragaloside IV can protect RGC from high-glucose induced damage and may benefit the patients with diabetic retinopathy.
    Zhonghua yi xue za zhi 08/2012; 92(30):2104-7.
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    ABSTRACT: Exendin-4 is a peptide resembling glucagon-like peptide-1 (GLP-1), which has protective effects on nerve cells. However, the effects of Exendin-4 on retinal ganglion cells (RGC) are still under clear. The purpose of the present study is to demonstrate that exenatide prevents high- or low-glucose-induced retinal ganglion cell impairment. We observed the expression of GLP-1R in RGC-5 cells by immunofluorescence and Western blot. To investigate the effect of exenatide on RGC-5 cells incubated different glucose concentrations, CCK-8 measured the survival rates and electron microscopy detected cellular injury. The expression levels of Bcl-2 and Bax were analyzed by immunocytochemistry and Western blot. Exenatide protects RGC-5 from high- or low-glucose-induced cellular injury and the optimum concentration was 0.5μg/ml. Exenatide can inhibit high- or low-glucose-induced mitochondrial changes. Exenatide protects RGC-5 from high- or low-glucose-induced Bax increased and Bcl-2 decreased. Furthermore, the protective effect of exenatide could be inhibited by Exendin (9-39). These findings indicate that exenatide shows a neuroprotective effect for different glucose concentrations-induced RGC-5 cells injury. Exenatide could protect RGC-5 cells from degeneration or death, which may protect retinal function and have a potential value for patients with diabetic retinopathy.
    Peptides 06/2012; 37(1):25-31. · 2.52 Impact Factor
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    ABSTRACT: Exenatide (exendin-4 analogue) is widely used in clinics and shows a neuroprotective effect. The main objectives of the present study were to prove that retinal ganglion cells (RGC-5) express GLP-1R, to ascertain whether exenatide prevents a high-glucose-induced RGC-5 impairment, to determine the appropriate concentration of exenatide to protect RGC-5 cells, and to explore the neuroprotective mechanisms of exenatide. Immunofluorescence and Western blot analyses demonstrated that RGC-5 cells express GLP-1R. We incubated RGC-5 cells with 25 mM glucose prior to incubation with either 25 mM glucose, 55 mM glucose (high), high glucose plus exenatide or high glucose plus a GLP-1R antagonist. The survival rates of the cells were measured by CCK-8, and cellular injury was detected by electron microscopy. There were statistical differences between the high-glucose group and the control group (P<0.05). Exenatide improved the survival rate of the cells and suppressed changes in the mitochondrial morphology. The optimum concentration of exenatide to protect the RGC-5 cells from high-glucose-induced RGC injury was 0.5 μg/ml, and this protective effect could be inhibited by exendin (9-39). To further study the mechanism underlying the beneficial effects of exenatide, the expression levels of cytochrome c, Bcl-2, Bax and caspase-3 were analysed by Western blot. The present study showed that treatment with exenatide significantly inhibited cytochrome c release and decreased the intracellular expression levels of Bax and caspase-3, whereas Bcl-2 was increased (P<0.05). These results suggested that GLP-1R activation can inhibit the cellular damage that is induced by high glucose. A mitochondrial mechanism might play a key role in the protective effect of exenatide on the RGC-5 cells, and exenatide might be beneficial for patients with diabetic retinopathy.
    Neurochemistry International 04/2012; 61(1):1-6. · 2.66 Impact Factor
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    ABSTRACT: The aim of the study was to investigate the protein expression of hypermethylated in cancer 1 (HIC1 ) and phosphatase and tensin homologue (PTEN) genes and to study their mRNA expressions in normal and diabetic pancreatic islet cells in rats in order to try and identify the functions of these genes in the development and advancement of diabetes. We further aimed to analyze the expression of mammalian target of rapamycin (mTOR), which is regulated by PTEN and to investigate the possible mechanism of PTEN affecting the function of diabetic islet cells. The expressions of HIC1, PTEN and mTOR genes were examined in the pancreatic islets of 20 normal male Wistar rats and 47 diabetic male Wistar rats by immunohistochemistry, Western blot, RT-PCR and real-time RT-PCR. Results showed that expressions of HIC1 and PTEN in protein and mRNA levels were lower in pancreatic islets of diabetic rats than in normal rats. Expressions of mTOR in protein and mRNA levels were higher in pancreatic islets of diabetic rats than in the normal rats. Marked apoptosis of pancreatic islet cells was observed in 29 cases (29/47, 61.7%) in diabetic rats, but not in the remaining 18 (18/47, 38.3%) diabetic rats. The down-regulation of HIC1 and PTEN and up-regulation of mTOR in protein and mRNA level are positively correlated with functional impairment of islet cells in diabetic rats. From this study we conclude that HIC1, PTEN and mTOR cannot be recognized as the key influencing factors promoting pancreatic islet cells apoptosis of diabetic rats; however, lower expressions of HIC1 and PTEN and higher expression of mTOR may affect the function of the pancreatic islet cells in diabetic rats.
    Acta histochemica 05/2011; 113(3):340-8. · 1.61 Impact Factor
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    ABSTRACT: Obestatin is a recently discovered gastrointestinal hormone. It might play a role in the pathophysiology of obesity. We tried to investigate the expression of obestatin in gastric body mucosa in overweight (BMI>or=24 kg/m(2))/obese (BMI>or=28 kg/m(2)) patients. Thirty overweight/obese patients and 20 healthy controls were included in the study. Biopsy specimens of gastric mucosa were obtained from the middle body of the greater curvature. Obestatin expression in gastric mucosa was evaluated by immunohistochemistry. Fasting plasma obestatin levels were measured by radioimmunoassay. The number of obestatin-positive cells in gastric body mucosa was significantly lower in overweight and obese patients than that in healthy subjects. The plasma concentrations of obestatin were also decreased in overweight and obese patients. There was a positive correlation between the numbers of obestatin-positive cells in the gastric body mucosa and circulating obestatin levels. The results indicate that overweight and obese subjects have a reduction in the number of obestatin-positive cells in gastric body mucosa.
    Peptides 11/2009; 31(2):291-6. · 2.52 Impact Factor
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    ABSTRACT: Ghrelin is a peptide hormone involved in human energy homeostasis. Obestatin is a recently discovered active peptide derived from preproghrelin. It seemed that obestatin was a physiologic opponent of ghrelin. Helicobacter pylori infection may be associated with appetite and nutrition. We compared the plasma ghrelin/obestatin ratio in H. pylori-positive and -negative groups. People undergoing an annual health checkup were included. Helicobacter pylori status was based on serologic and carbon-13 urea breath findings. Fifty adults with H. pylori infection and 50 adults matched by age and body mass index without H. pylori infection were enrolled in this study. Plasma ghrelin and obestatin levels were measured by radioimmunoassay. Ghrelin concentrations and ghrelin/obestatin ratios were lower in the H. pylori-positive group than in the H. pylori-negative group. There was no significant difference in circulating obestatin between those with and without H. pylori infection. In all subjects, the ghrelin/obestatin ratio was negatively correlated with body mass index, the homeostasis model of assessment for insulin resistance, and serum levels of triacylglycerol. There was a positive correlation between circulating obestatin and ghrelin levels. Helicobacter pylori infection was associated with a reduction in the circulating ghrelin/obestatin ratio in Chinese adults.
    Nutrition 02/2009; 25(5):506-11. · 2.86 Impact Factor
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    ABSTRACT: Hyperglycemia initiates a sequence of events that leads to the development of diabetic retinopathy. We explored the effect of re-institution of good blood glucose control on apoptosis and apoptosis related genes (Bax and Bcl-2) in the retina of diabetic rats. Fifty male Wistar rats randomly divided into five groups : normal control group (CON), diabetic rats with high blood glucose levels for 8 months group (DM) ,diabetic rats with good blood glucose control for 8 months group (DM(1)),diabetic rats with poor blood glucose control for 2 month followed by good blood glucose control for six additional months group (DM(2)), rats with poor blood glucose control for 4 months followed by good blood glucose levels for four additional months group (DM(3)). Expression of Bax and Bcl-2 in the retina was studied by immunohistochemistry and the apoptotic cells were stained using the TUNEL method. The apoptotic cell, expression of Bax and Bcl-2 and the ratio of Bax to Bcl-2 in the retina was increased in DM group compared with normal rats' (P < 0.01). There was no significant difference in apoptotic cells and the ratio of Bax to Bcl-2 between DM(1) group and CON group. The number of TUNEL positive cells and Bax to Bcl-2 ratio was partially reversed in DM(2) group. But glucose control had no effect on the apoptotic cells and the expression of Bax and Bcl-2 in DM(3) group. There was a positive correlation between apoptotic cells and Bax/Bcl-2 ratio in the retina (r = 0.808, P < 0.01). Good blood glucose control at early stage can decrease the number of apoptotic cells in the retina; the decreased apoptosis is correlated with the down-regulation of Bax to Bcl-2 ratio.
    Molecular Biology Reports 12/2008; 36(7):1977-82. · 2.51 Impact Factor
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    ABSTRACT: Obestatin is a recently discovered active peptide isolated from the stomach. The purpose of the present study was to investigate the modification of plasma obestatin levels in men with chronic atrophic gastritis. Men older than 65 years undergoing upper gastrointestinal endoscopy were included. All patients with chronic atrophic gastritis underwent multiple biopsies. Fasting plasma obestatin and ghrelin levels were examined in 50 men with chronic atrophic gastritis and 50 healthy men. Plasma obestatin levels were significantly lower in patients with chronic atrophic gastritis than in healthy subjects. Plasma ghrelin levels and ghrelin to obestatin ratio was decreased in men with chronic atrophic gastritis. There was a significant relationship between atrophy and decreased obestatin. A negative correlation was found between circulating obestatin levels and body mass index (BMI) in healthy subjects, but not in patients with chronic atrophic gastritis. The data indicated that chronic atrophic gastritis influenced plasma obestatin levels as well as ghrelin to obestatin ratio in elderly men.
    Peptides 07/2008; 29(10):1749-54. · 2.52 Impact Factor
  • Diabetes research and clinical practice 02/2008; 79(1):e5-6. · 2.74 Impact Factor
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    ABSTRACT: To investigate the role of insulin-like growth factor-1 receptor mRNA (IGF-1R mRNA) in diabetic cardiomyopathy. Alloxan of the doses of 150 and 200 mg/kg was injected intraperitoneally into 20 male Wistar rats respectively so as to establish type 1 diabetes mellitus models (Groups B and C). The rats were used as normal controls (Groups A). Three months later the rats were killed and blood samples were collected to undergo examination of plasma glucose, insulin, glycated hemoglobin (HbA1c), and C peptide. The hearts were taken out to undergo light and transmission electron microscopy and in situ hybridization to detect the expression of IGF-1R mRNA in the myocardium. The levels of plasma glucose, HbA1c, insulin and C peptide of Groups B and C were all significantly higher than those of Group A (all P < 0.01), and the levels of plasma glucose, HbA1c, insulin and C peptide of Group C being significantly higher than those of Group B too (all P < 0.01). Expression of IGF-1R mRNA was found in the myocardium of Groups A, B and C with the distribution areas of 20%, 30%, and 38% respectively. The expression of IGF-1R mRNA in myocardium was positively correlated with blood glucose and HbA1c (r = 0.869, 0.865, both P < 0.01). The increased expression of IGF-1R mRNA in the myocardium may play an important role in the progression of diabetic cardiomyopathy.
    Zhonghua yi xue za zhi 05/2007; 87(18):1249-51.
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    ABSTRACT: To detect the oxidative DNA damage in diabetic patients and to investigate the relationship of oxidative DNA damage with diabetes and diabetic nephropathy. Single cell gel electrophoresis (SCGE) was used to detect the DNA strand breaks in peripheral blood lymphocytes, and oxidative DNA damage product and serum 8-OHdG were determined by a competitive ELISA in 47 cases, including 25 patients without diabetic complications, 22 patients with diabetic nephropathy and 25 normal control subjects. Diabetic patients showed greater oxidative damage to DNA. The percentage of comet cells and the length of DNA migration (comet tail length) of peripheral blood lymphocytes were significantly increased in patients with diabetes, and significantly higher in patients with diabetic nephropathy than in diabetic patients without vascular complications (P < 0.05). There was a significant increase in serum 8-OHdG in diabetic patients compared with normal subjects (P < 0.05). Moreover, serum 8-OHdG was much higher in patients with diabetic nephropathy than in diabetic patients without vascular complications (P < 0.05). There is severe oxidative DNA damage in diabetic patients. Enhanced oxidative stress may be associated with diabetes, especially in patients with diabetic nephropathy.
    Biomedical and Environmental Sciences 05/2007; 20(2):160-3. · 1.15 Impact Factor
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    ABSTRACT: To observe the therapeutic effect of eye-needling combined with medication for treatment of ophthalmoplegia and explore the possible mechanism. One hundred and twenty cases were randomly divided into a treatment group and a control group. According to etiological factors, the control group were treated with medication and the treatment group with the medication plus eye-acupuncture at main point ocular muscles. Changes of the rima oculi, the range of ocular movement and the dialopia angle after treatment were recorded and statistically analyzed in the two groups. The total effective rate was 93.4% and the cured rate was 54.1% in the treatment group, and 74.6% and 18.6% in the control group, with significant difference between the two groups (P < 0. 01). Eye-needling combined with medication has an obvious therapeutic effect which is better than simple medication for ophthalmoplegia.
    Zhongguo zhen jiu = Chinese acupuncture & moxibustion 03/2007; 27(3):165-8.