Role of Autophagy in Granulocyte-Colony Stimulating Factor Induced Anti-Apoptotic Effects in Diabetic Cardiomyopathy

Background@#We previously, reported that granulocyte-colony stimulating factor (G-CSF) reduces cardiomyocyte apoptosis in diabetic cardiomyopathy. However, the underlying mechanisms are not yet fully understood. Therefore, we investigated whether the mechanisms underlying of the anti-apoptotic effects of G-CSF were associated with autophagy using a rat model of diabetic cardiomyopathy. @*Methods@#Diabetic cardiomyopathy was induced in rats through a high-fat diet combined with low-dose streptozotocin and the rats were then treated with G-CSF for 5 days. Rat H9c2 cardiac cells were cultured under high glucose conditions as an in vitro model of diabetic cardiomyopathy. The extent of apoptosis and protein levels related to autophagy (Beclin-1, microtubule-binding protein light chain 3 [LC3]-II/LC3-I ratio, and P62) were determined for both models. Autophagy determination was performed using an Autophagy Detection kit. @*Results@#G-CSF significantly reduced cardiomyocyte apoptosis in the diabetic myocardium in vivo and led to an increase in Beclin-1 level and the LC3-II/LC3-I ratio, and decreased P62 level. Similarly, G-CSF suppressed apoptosis, increased Beclin-1 level and LC3-II/LC3-I ratio, and decreased P62 level in high glucose-induced H9c2 cardiac cells in vitro. These effects of G-CSF were abrogated by 3-methyladenine, an autophagy inhibitor. In addition, G-CSF significantly increased autophagic flux in vitro. @*Conclusion@#Our results suggest that the anti-apoptotic effect of G-CSF might be significantly associated with the up-regulation of autophagy in diabetic cardiomyopathy.

Role of Autophagy in Granulocyte-Colony Stimulating Factor Induced Anti-Apoptotic Effects in Diabetic Cardiomyopathy

Background@#We previously, reported that granulocyte-colony stimulating factor (G-CSF) reduces cardiomyocyte apoptosis in diabetic cardiomyopathy. However, the underlying mechanisms are not yet fully understood. Therefore, we investigated whether the mechanisms underlying of the anti-apoptotic effects of G-CSF were associated with autophagy using a rat model of diabetic cardiomyopathy. @*Methods@#Diabetic cardiomyopathy was induced in rats through a high-fat diet combined with low-dose streptozotocin and the rats were then treated with G-CSF for 5 days. Rat H9c2 cardiac cells were cultured under high glucose conditions as an in vitro model of diabetic cardiomyopathy. The extent of apoptosis and protein levels related to autophagy (Beclin-1, microtubule-binding protein light chain 3 [LC3]-II/LC3-I ratio, and P62) were determined for both models. Autophagy determination was performed using an Autophagy Detection kit. @*Results@#G-CSF significantly reduced cardiomyocyte apoptosis in the diabetic myocardium in vivo and led to an increase in Beclin-1 level and the LC3-II/LC3-I ratio, and decreased P62 level. Similarly, G-CSF suppressed apoptosis, increased Beclin-1 level and LC3-II/LC3-I ratio, and decreased P62 level in high glucose-induced H9c2 cardiac cells in vitro. These effects of G-CSF were abrogated by 3-methyladenine, an autophagy inhibitor. In addition, G-CSF significantly increased autophagic flux in vitro. @*Conclusion@#Our results suggest that the anti-apoptotic effect of G-CSF might be significantly associated with the up-regulation of autophagy in diabetic cardiomyopathy.

Role of MicroRNA-34a in Anti-Apoptotic Effects of Granulocyte-Colony Stimulating Factor in Diabetic Cardiomyopathy

BACKGROUND: Recent studies have shown that microRNAs (miRNAs) are involved in the process of cardiomyocyte apoptosis. We have previously reported that granulocyte-colony stimulating factor (G-CSF) ameliorated diastolic dysfunction and attenuated cardiomyocyte apoptosis in a rat model of diabetic cardiomyopathy. In this study, we hypothesized a regulatory role of cardiac miRNAs in the mechanism of the anti-apoptotic effect of G-CSF in a diabetic cardiomyopathy rat model.METHODS: Rats were given a high-fat diet and low-dose streptozotocin injection and then randomly allocated to receive treatment with either G-CSF or saline. H9c2 rat cardiomyocytes were cultured under a high glucose (HG) condition to induce diabetic cardiomyopathy in vitro. We examined the extent of apoptosis, miRNA expression, and miRNA target genes in the myocardium and H9c2 cells.RESULTS: G-CSF treatment significantly decreased apoptosis and reduced miR-34a expression in diabetic myocardium and H9c2 cells under the HG condition. G-CSF treatment also significantly increased B-cell lymphoma 2 (Bcl-2) protein expression as a target for miR-34a. In addition, transfection with an miR-34a mimic significantly increased apoptosis and decreased Bcl-2 luciferase activity in H9c2 cells.CONCLUSION: Our results indicate that G-CSF might have an anti-apoptotic effect through down-regulation of miR-34a in a diabetic cardiomyopathy rat model.

Local Injection of Granulocyte-Colony Stimulating Factor Accelerates Wound Healing in a Rat Excisional Wound Model

A systemic treatment of granulocyte-colony stimulating factor (G-CSF) is known to improve healings of damaged tissues. However, recent studies suggested local actions of G-CSF on the healing processes of damaged tissues. We investigated the treatment effect of locally injected G-CSF and compared to that of systemically injected G-CSF in a rat model. A wound was created on the rat dorsum and treated either by local injection or by systemic injection of G-CSF. Wound healing rate, deposition of collagen, and gene expression were evaluated. G-CSF receptor (G-CSFR) protein was detected by Western blotting. The wound healing rate in the local injection group was significantly higher than that in the systemic injection group at days 9 and 15; it was also significantly higher than that in the control group at days 3, 9, and 15. The expression of G-CSFR protein in wound tissues was higher than in normal skin tissues. The local injection of G-CSF is more effective than systemic injection of G-CSF in promoting wound healing, which may implicate the local action of G-CSF treatment in wound healing processes.

Proposal on the Establishment of Telemedicine Guidelines for Korea / 대한의료정보학회지

OBJECTIVES: An official guideline must be prepared for legalizing the doctor-patient telemedicine system based on the evaluations of the ongoing telemedicine demonstration project performed by the Korean government. In this study, critical items of the Korean telemedicine guideline are suggested based on the guidelines of developed countries. METHODS: To investigate the telemedicine guidelines of developed countries, a keyword of 'telemedicine guidelines' was used for Google search to find out US, Australian, and Japanese guidelines. The common items included in two or more of the followings were screened: US Core Operational Guidelines for Telehealth Services Involving Provider-Patient Interactions, the Australian New South Wales (NSW) Agency for Clinical Innovation Guidelines for the use of Telehealth for Clinical and Non Clinical Settings in NSW, and the Japanese Guidelines for the practice of home telemedicine. RESULTS: A total of 22 common items of the following four domains, which could be used for the Korean guideline were screened: the common features in overall considerations (6 items), the common features in clinical considerations (6 items), the common features in technical considerations (5 items), and the common features in privacy considerations (5 items). These 22 items were suggested as the critical items of the Korean telemedicine guideline. CONCLUSIONS: The screened 22 items of the telemedicine guideline must be further organized for details. Additional studies and professional opinions on the telemedicine cases and on the guidelines of developed countries are required to establish the Korean guideline in the near future.