Diabetes & Metabolism Journal

Original Articles

In vivo Corneal Confocal Microscopy and Nerve Growth Factor in Diabetic Microvascular Complications.: Ji Sun Nam, Young Jae Cho, Tae Woong Noh, Chul Sik Kim, Jong Suk Park, Min ho Cho, Hai Jin Kim, Ji Eun Yoon, Han Young Jung, Eun Seok Kang, Yu Mie Rhee, Hyung Keun Lee, Chul Woo Ahn, Bong Soo Cha, Eun Jig Lee, Sung Kil Lim, Kyung Rae Kim, Hyun Chul Lee; Korean Diabetes J. 2007;31(4):351-361. Published online July 1, 2007; DOI: https://doi.org/10.4093/jkda.2007.31.4.351

2,773 View
21 Download

Abstract PDF: BACKGROUND
In vivo corneal confocal microscopy (IVCCM) is being recognized as a non-invasive, early diagnostic tool for diabetic neuropathy, for it provides a clear image of corneal subbasal nerve plexus in detail. Nerve growth factors (NGF) are believed to regulate peripheral and central nervous system, neuronal differentiation, and regeneration of damaged nerves, and their role in diabetic neuropathy is being emphasized these days. Moreover, NGFs and receptors are also expressed in retina and renal mesangial cells, suggesting their possible role in the common pathogenesis of diabetic microvascular complications. We plan to examine corneal structures of diabetic patients and compare IVCCM with conventional tools and analyze their serum and tear NGF levels. METHODS: IVCCM, nerve conduction velocity (NCV), and serum, urine, and tear samplings were done to 42 diabetic patients. From IVCCM, we measured corneal nerve density, branch, and tortuosity, total corneal/epithelial thickness, and the number of endothelial/keratocyte cells, and we checked patients' biochemical profiles and serum and tear NGF levels. RESULTS: Patients with more severe neuropathy had less corneal endothelial cells (3105 +/- 218 vs. 2537 +/- 142 vs. 2350 +/- 73/mm3 vs. 1914 +/- 465/mm3, P = 0.02), higher serum NGF (36 +/- 15 vs. 60 +/- 57.66 vs. 80 +/- 57.63 vs. 109 +/- 60.81 pg/mL, P = 0.39) and tear NGF levels (135.00 +/- 11.94 vs. 304.29 +/- 242.44 vs. 538.50 +/- 251.92 vs. 719.50 +/- 92.63 pg/mL, P = 0.01). There was a positive correlation between neuropathy and corneal nerve tortuosity (r2 = 0.479, P = 0.044) and negative correlation between neuropathy and endothelial cell count (r2 = -0.709, P = 0.002). Interestingly, similar changes were seen in other microvascular complications as well. CONCLUSION: Our results provide a possibility of using novel tools, IVCCM and NGF, as common diagnostic tools for diabetic microvascular complications, but it should be followed by a large population study.

Effect of Nerve Growth Factor on Cultured Mouse Dorsal Root Ganglion Cells in Hyperglycemic Condition.: Byoung Hyun Park, Chung Gu Cho, Geun Young Jang, Ki Hun Kim, Seung Taeck Park; Korean Diabetes J. 2001;25(4):286-296. Published online August 1, 2001

1,108 View
23 Download

Abstract PDF: BACKGROUND
Multiple etiology of diabetic neuropathy has been proposed, including altered polyol metabolism, superoxide radical formation, protein glycation, vascular insufficiency, blunted nitric oxide production and neurotrophic factor (NTF) deficiency. Nerve growth factor (NGF) is a member and family of neurotrophic factors. NGF is produced in tissues innervated by its responsive neurons. In the peripheral nervous system, NGF messenger RNA (mRNA) is produced in target fields of small pain and temperature-mediating dorsal root ganglia (DRG) sensory neurons and sympathetic neurons. NGF has been shown to promote their survival, differentiation, and maintenance. However, the mechanism of neuronal damage in diabetes and the effect of NGF on diabetic neuropathy are not clear. METHODS: In order to clarify the effect of NGF, the changes of cell viability were evaluated by MTT assay on mouse cultured dorsal root ganglion cells which were grown with media containing concentrations of high glucose for inducing hyperglycemic condition. Furthermore, the neuroprotective effect of nerve growth factor (NGF) against hyperglycemia-induced dorsal root ganglion cell changes were also examined. RESULTS: 1. Cell viability of cultured mouse dorsal root ganglion cells treated with hyperglycemic media made with 15, 25 mM glucose was markedly decreased in a dose-dependent manner when compared with control medium (normoglycemic medium) containing concentration of 5.5 mM glucose (p<0.05). 2. Cultured dorsal root ganglion cells exposed to hyperglycemic medium made with 25 mM glucose for 72 hours showed morphological changes such as dissociations, loss of neurites and decrease of cell viability (p<0.05). 3. Pretreatment of 150 ng/mL NGF for 2 hours significantly increased the cell viability of cultured dorsal root ganglion cells which exposed to hyperglycemic medium (25 mM glucose for 72 hours). CONCLUSION: Findings from this study suggested that hyperglycemic condition induces the decrease of cell viability and morphological changes (loss of neurites, dissociation) on cultured dorsal root ganglion cells of mouse. Furthermore, selective neurotrophic factors such as NGF are very effective in preventing dysfunction and morphological changes of DRG cells induced by hyperglycemic condition.

Effect of Nerve Growth Factor on Cultured Rat Schwann Cells in Hyperglycemic Condition.: Geun Young Hyung, Kyoung Hee Kim, Seung Hoon Baek, Geun Young Jang, Chung Gu Cho; Korean Diabetes J. 2000;24(1):10-18. Published online January 1, 2001

1,105 View
20 Download

Abstract PDF: BACKGROUND
Nerve growth factor (NGF) is produced in tissues innervafed by its responsive neurons. In the peripheral nervous system, NGF messenger RNA (mRNA) is produced in target fields of small pain and temperature-mediating dorsal root ganglia (DRG) sensory neurons and sympathetic neurons. NGF receptors are expressed in these neurons, and NGF has been shown to promote their survival, differentiation, as well as maintenance. However, the mechanism of neuronal damage in diabetes and the effect of NGF on diabetic neuropathy are unclear. METHODS: in order to clarify the effect of hyperglycemia, the hyperglycemia-induced cytotoxic effects were evaluated by MTT assay on cultured rat Schwann cells, Schwann cells were grown with media containing concentrations of high glucose for inducing hyperglycemic condition. The neuroprotective effect of nerve growth factor (NGF) against hyperglycemia-induced Schwann cell changes were also examined. RESULT: 1. MMT50 value was at concentration of 25mM glucose after 72 hours, 2. Cell viability of cultured rat Schwann cells treated with hyperglycemic media made with 25~35mM glucose was markedly decreased in a dose-dependent manner when compared with control medium (normoglycemic medium) containing concentration of 5.5 mM glucose, While cell number did not show a dose- dependent decrease. 3. Cultured Schwann cells exposed to hyperglycemic medium made with 25mM glucose for 72 hours did nof show any morphological change as well as decrease of cell number. 4. Pretreatment of 10 ng/mL NGF for 2 hours increased remarkably the cell viability of cultured Schwann cells exposed to hyperglycemic medium(25mM glucose for 72 hours). CONCLUSIONS: The results from this study suggested that hyperglycemic condition induces the decrease of cell viability on cultured Schwann cells of rat. But it did not show the decrease of cell number and rnorphological change. The selective neurotrophic factors such as NGF are very effective in preventing dysfunction of cells induced by hyperglycemic condition.

First
Prev
Page of 1
Next
Last

Search