1.Telmisartan increases hepatic glucose production via protein kinase C ζ-dependent insulin receptor substrate-1 phosphorylation in HepG2 cells and mouse liver
Yeungnam University Journal of Medicine 2019;36(1):26-35
BACKGROUND: Dysregulation of hepatic glucose production (HGP) contributes to the development of type 2 diabetes mellitus. Telmisartan, an angiotensin II type 1 receptor blocker (ARB), has various ancillary effects in addition to common blood pressure-lowering effects. The effects and mechanism of telmisartan on HGP have not been fully elucidated and, therefore, we investigated these phenomena in hyperglycemic HepG2 cells and high-fat diet (HFD)-fed mice.METHODS: Glucose production and glucose uptake were measured in HepG2 cells. Expression levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase α (G6Pase-α), and phosphorylation levels of insulin receptor substrate-1 (IRS-1) and protein kinase C ζ (PKCζ) were assessed by western blot analysis. Animal studies were performed using HFD-fed mice.RESULTS: Telmisartan dose-dependently increased HGP, and PEPCK expression was minimally increased at a 40 μM concentration without a change in G6Pase-α expression. In contrast, telmisartan increased phosphorylation of IRS-1 at Ser302 (p-IRS-1-Ser302) and decreased p-IRS-1-Tyr632 dose-dependently. Telmisartan dose-dependently increased p-PKCζ-Thr410 which is known to reduce insulin action by inducing IRS-1 serine phosphorylation. Ectopic expression of dominant-negative PKCζ significantly attenuated telmisartan-induced HGP and p-IRS-1-Ser302 and -inhibited p-IRS-1-Tyr632. Among ARBs, including losartan and fimasartan, only telmisartan changed IRS-1 phosphorylation and pretreatment with GW9662, a specific and irreversible peroxisome proliferator-activated receptor γ (PPARγ) antagonist, did not alter this effect. Finally, in the livers from HFD-fed mice, telmisartan increased p-IRS-1-Ser302 and decreased p-IRS-1-Tyr632, which was accompanied by an increase in p-PKCζ-Thr410.CONCLUSION: These results suggest that telmisartan increases HGP by inducing p-PKCζ-Thr410 that increases p-IRS-1-Ser302 and decreases p-IRS-1-Tyr632 in a PPARγ-independent manner.
Animals
;
Blotting, Western
;
Diabetes Mellitus, Type 2
;
Diet, High-Fat
;
Ectopic Gene Expression
;
Glucose
;
Glucose-6-Phosphatase
;
Hep G2 Cells
;
Insulin Receptor Substrate Proteins
;
Insulin
;
Liver
;
Losartan
;
Mice
;
Peroxisomes
;
Phosphoenolpyruvate
;
Phosphorylation
;
Protein Kinase C
;
Protein Kinases
;
Receptor, Angiotensin, Type 1
;
Receptor, Insulin
;
Serine
2.Telmisartan increases hepatic glucose production via protein kinase C ζ-dependent insulin receptor substrate-1 phosphorylation in HepG2 cells and mouse liver
Yeungnam University Journal of Medicine 2019;36(1):26-35
BACKGROUND:
Dysregulation of hepatic glucose production (HGP) contributes to the development of type 2 diabetes mellitus. Telmisartan, an angiotensin II type 1 receptor blocker (ARB), has various ancillary effects in addition to common blood pressure-lowering effects. The effects and mechanism of telmisartan on HGP have not been fully elucidated and, therefore, we investigated these phenomena in hyperglycemic HepG2 cells and high-fat diet (HFD)-fed mice.
METHODS:
Glucose production and glucose uptake were measured in HepG2 cells. Expression levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase α (G6Pase-α), and phosphorylation levels of insulin receptor substrate-1 (IRS-1) and protein kinase C ζ (PKCζ) were assessed by western blot analysis. Animal studies were performed using HFD-fed mice.
RESULTS:
Telmisartan dose-dependently increased HGP, and PEPCK expression was minimally increased at a 40 μM concentration without a change in G6Pase-α expression. In contrast, telmisartan increased phosphorylation of IRS-1 at Ser302 (p-IRS-1-Ser302) and decreased p-IRS-1-Tyr632 dose-dependently. Telmisartan dose-dependently increased p-PKCζ-Thr410 which is known to reduce insulin action by inducing IRS-1 serine phosphorylation. Ectopic expression of dominant-negative PKCζ significantly attenuated telmisartan-induced HGP and p-IRS-1-Ser302 and -inhibited p-IRS-1-Tyr632. Among ARBs, including losartan and fimasartan, only telmisartan changed IRS-1 phosphorylation and pretreatment with GW9662, a specific and irreversible peroxisome proliferator-activated receptor γ (PPARγ) antagonist, did not alter this effect. Finally, in the livers from HFD-fed mice, telmisartan increased p-IRS-1-Ser302 and decreased p-IRS-1-Tyr632, which was accompanied by an increase in p-PKCζ-Thr410.
CONCLUSION
These results suggest that telmisartan increases HGP by inducing p-PKCζ-Thr410 that increases p-IRS-1-Ser302 and decreases p-IRS-1-Tyr632 in a PPARγ-independent manner.
3.A case of polyarteritis nodosa, possibly of cutaneous type.
Won Woo LEE ; Kae Yong HWANG ; Duck Ha KIM ; Kyeong Sook CHO
Korean Journal of Dermatology 1991;29(4):557-561
No abstract available.
Polyarteritis Nodosa*
4.Four cases of malignant mixed Mullerian tumors.
Won Sil MOON ; Chi Hoon LEE ; Ki Eun HONG ; Hae Kyung LEE ; Kae Hyun NAM ; Dong Wha LEE ; Tai Ho CHO
Korean Journal of Obstetrics and Gynecology 1991;34(12):1801-1808
No abstract available.
6.A case of fetal skelectal anomaly of Campomelic syndrome.
Suk Kyung KIM ; Hyeon Chul KIM ; Seung Joo SHIN ; Mee Wha LEE ; You Me LEE ; Jin Ho CHO ; Yun Jung CHOI ; Kae Won KWON
Korean Journal of Obstetrics and Gynecology 2000;43(2):311-314
Campomelic syndrome is a very rare skeletal dysplasia with a characteristic pattern of deformity involving the proximal and distal extremities, pelvic and shoulder girdles, thoracic cage and palate. Respiratory compromise often leads to death in early infancy. Etiology has not been determined although evidence suggests genetic heterogeneity. Cytogenetic study revealed high incidence of a 46,XY karyotype in phenotypic females. Recently, we had experienced a case of campomelic dysplasia at amenorrhea 30weeks and termination was done, so we report with a brief review of literature.
Amenorrhea
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Campomelic Dysplasia*
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Congenital Abnormalities
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Cytogenetics
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Extremities
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Female
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Genetic Heterogeneity
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Humans
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Incidence
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Karyotype
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Palate
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Shoulder
7.Adenosine-Prefabricated Adipose Tissue Improves Fat Graft Survival by Promoting VEGF-Dependent Angiogenesis
Jiyeon CHANG ; Woo Jin SONG ; Shindy SOEDONO ; Sharlene SHARLENE ; Yeong Jin KIM ; Chang Yong CHOI ; Kae Won CHO
Tissue Engineering and Regenerative Medicine 2022;19(5):1051-1061
BACKGROUND:
Angiogenesis plays an important role in determining the fat graft survival. However, clinical preconditioning techniques that target angiogenesis during fat grafting have not been established so far. Adenosine has emerged as a regulator of angiogenesis under hypoxic conditions; therefore, the aim of this study was to investigate the effects and underlying mechanisms of adenosine prefabrication on fat graft survival.
METHODS:
In the first animal study, a total of 32 mice were transplanted with fat prefabricated with vehicle (Control, N = 16) or adenosine (Adenosine, N = 16). In the second animal study, 24 mice were divided into three groups based on the type of fat graft: Control (N = 8), Adenosine (N = 8), and Axitinib (cotreatment of adenosine with axitinib, N = 8). At 1- and 4-weeks post-transplantation, grafts were evaluated by histopathological and biochemical assessment. Adenosineinduced vascular endothelial growth factor (VEGF) production and angiogenesis were determined using cell cultures.
RESULTS:
The retention volumes of fat grafts in the adenosine group were significantly increased until 4 weeks. Fat grafts from the adenosine group exhibited greater structural integrity, reduced fibrosis, and increased blood vessels. The expression levels of angiogenesis-related genes, Vegfa, Vegfr1, Vegfr2, and Vwf, were elevated in the adenosine group. Furthermore, adenosine upregulated VEGF production in preadipocytes, thereby enhancing the migration of endothelial cells. Treatment with the axitinib, VEGF receptor inhibitor, abrogated the adenosine-induced angiogenesis in the fat grafts.
CONCLUSION
Adenosine prefabrication in fat improved the graft survival by enhancing angiogenesis through the VEGF/VEGFR axis in the preadipocytes and endothelial cells. Therefore, this method may be used as a novel strategy to increase the retention rate in fat grafts.
8.A Case of Ascites by Pseudomembranous Colitis, Initially Diagnosed Malignant Asites.
Chang Uck KIM ; Jin Won CHO ; Jin Young SONG ; Do Kyun JIN ; Su Jin HONG ; Sea Hyub KAE ; Jin LEE ; Sang Aun JOO
Korean Journal of Gastrointestinal Endoscopy 2001;22(4):225-228
Pseudomembranous colitis (PMC) is mostly related with the antibiotics and it presents with diarrhea, abdominal pain, fever, hypoalbuminemia and hypovolemia. In the clinical course of pseudomembranous colitis (PMC), ascites is a rare presentation, and high elevation of carcinoembryonic antigen (CEA) associated with PMC is also a very rare presentation. We experienced a case taken cephalosporin group antibiotics for six weeks and presented with fever, abdominal pain, severe diarrhea, and massive ascites. During evaluation, we found low serum-ascites albumin gradient and high level of CEA in both ascites and plasma. With the impression of hidden malignancy, the special studies were done, but PMC was only found without malignancy. After vancomycin therapy, all symptoms were relieved and CEA level declined.
Abdominal Pain
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Anti-Bacterial Agents
;
Ascites*
;
Carcinoembryonic Antigen
;
Diarrhea
;
Enterocolitis, Pseudomembranous*
;
Fever
;
Hypoalbuminemia
;
Hypovolemia
;
Plasma
;
Vancomycin
9.Macrofungal Survey of the Tian Shan Mountains, Kyrgyzstan
Sung Eun CHO ; Jong Won JO ; Nam Kyu KIM ; Young Nam KWAG ; Sang Kuk HAN ; Kae Sun CHANG ; Seung Hwan OH ; Chang Sun KIM
Mycobiology 2019;47(4):378-390
The Tian Shan mountain system is one of the large mountain ranges located in Central Asia. This region is globally recognized as mountain ranges, offering inestimable wealth in fauna and flora with significant biodiversity values. We surveyed macrofungal diversity of Tian Shan in Kyrgyzstan from 2016 to 2018. A collection of macrofungi was made, and these were subjected to sequence comparisons and phylogenetic analysis to ensure the identity of the collected macrofungi. Of those collected, 95 out of 100 specimens were successfully sequenced and compared with those of other related species retrieved from GenBank. The sequenced specimens were classified into 2 phyla, 8 orders, 24 families, 47 genera, and 57 species, based on current taxonomic concepts (combining morphology and phylogeny). To the best of our knowledge, this study provides the first well-documented checklist and phylogenetic analysis of macrofungi recovered from the Tian Shan mountains in Kyrgyzstan.