scholarly journals Kill two birds with one stone: making multi-transgenic pre-diabetes mouse models through insulin resistance and pancreatic apoptosis pathogenesis

Author(s):  
Siyuan Kong ◽  
Jinxue Ruan ◽  
Kaiyi Zhang ◽  
Bingjun Hu ◽  
Yuzhu Cheng ◽  
...  

Background. Type 2 diabetes, a chronic disease to which susceptibility is hereditary, is characterized by insulin resistance accompanied by defective insulin secretion. Mouse models, especially transgenic mice, play an important role in medical research. However, the transgenic mouse models that have been used in diabetes research are involved with single transgenes, focusing on the insulin gene or its mutants. Thus they mainly provide information related to Type 1 diabetes. Methods. Here, we attempted to focus comprehensively on genes related to pancreatic islet damage, peripheral insulin resistance and related environmental inducing factors by generating single-transgenic mice (CHOP), dual-transgenic mice (hIAPP-CHOP) and triple-transgenic mice (11β-HSD1-hIAPP-CHOP). The latter two types of transgenic animals were induced with high-fat, high-sucrose diets (HFHSD). We evaluated and analyzed the diabetes-related symptoms and the histopathological and immunohistochemical features of the transgenic animals. Results. Specifically, in the triple-transgene animals, the results of intraperitoneal glucose tolerance tests (IPGTT) began to change 60 days after induction (p<0.001). After 190 days of induction, the body weights (p<0.01) and plasma glucose levels of the animals in the Tg group were higher than those of the animals in the Nc group. After the mice were sacrificed, large amounts of lipid were found deposited in the adipose tissues (p<0.01) and ectopically deposited in the non-adipose tissues (p<0.05 or 0.01) of the animals in the Tg HFHSD group. The weights of the kidneys and hearts of the Tg animals were significantly increased (p<0.01). Serum C-P was decreased due to transgene effects, and insulin levels were increased due to the effects of the high-fat high-sucrose diet in the Tg HFHSD group, indicating that damaged insulin secretion and insulin resistance hyperinsulinemia existed simultaneously in these animals. The serum corticosterone levels of the animals in the Tg group were slightly higher than those of the Nc animals due to the effects of the 11βHSD-1 transgene and obesity. In the Tg HFHSD group, hepatic adipose deposition was more severe and the pancreatic islet area was enlarged under compensation, accompanying apoptosis. In the Tg ControlD group, hepatic adipose deposition was also severe, pancreatic islets were damaged, and their areas were decreased (p<0.05), and apoptosis of pancreatic cells occurred. Taken together, these data show that the transgenes led to early-stage pathological changes characteristic of type 2 diabetes in the triple-transgene HFHSD group. The disease of triple-transgenic mice was more severe than that of dual or single-transgenic mice. Conclusion. The use of multi-transgenes involved in insulin resistance and pancreatic apoptosis is a better way to generate polygene-related early-stage diabetes models.

2017 ◽  
Author(s):  
Siyuan Kong ◽  
Jinxue Ruan ◽  
Kaiyi Zhang ◽  
Bingjun Hu ◽  
Yuzhu Cheng ◽  
...  

Background. Type 2 diabetes, a chronic disease to which susceptibility is hereditary, is characterized by insulin resistance accompanied by defective insulin secretion. Mouse models, especially transgenic mice, play an important role in medical research. However, the transgenic mouse models that have been used in diabetes research are involved with single transgenes, focusing on the insulin gene or its mutants. Thus they mainly provide information related to Type 1 diabetes. Methods. Here, we attempted to focus comprehensively on genes related to pancreatic islet damage, peripheral insulin resistance and related environmental inducing factors by generating single-transgenic mice (CHOP), dual-transgenic mice (hIAPP-CHOP) and triple-transgenic mice (11β-HSD1-hIAPP-CHOP). The latter two types of transgenic animals were induced with high-fat, high-sucrose diets (HFHSD). We evaluated and analyzed the diabetes-related symptoms and the histopathological and immunohistochemical features of the transgenic animals. Results. Specifically, in the triple-transgene animals, the results of intraperitoneal glucose tolerance tests (IPGTT) began to change 60 days after induction (p<0.001). After 190 days of induction, the body weights (p<0.01) and plasma glucose levels of the animals in the Tg group were higher than those of the animals in the Nc group. After the mice were sacrificed, large amounts of lipid were found deposited in the adipose tissues (p<0.01) and ectopically deposited in the non-adipose tissues (p<0.05 or 0.01) of the animals in the Tg HFHSD group. The weights of the kidneys and hearts of the Tg animals were significantly increased (p<0.01). Serum C-P was decreased due to transgene effects, and insulin levels were increased due to the effects of the high-fat high-sucrose diet in the Tg HFHSD group, indicating that damaged insulin secretion and insulin resistance hyperinsulinemia existed simultaneously in these animals. The serum corticosterone levels of the animals in the Tg group were slightly higher than those of the Nc animals due to the effects of the 11βHSD-1 transgene and obesity. In the Tg HFHSD group, hepatic adipose deposition was more severe and the pancreatic islet area was enlarged under compensation, accompanying apoptosis. In the Tg ControlD group, hepatic adipose deposition was also severe, pancreatic islets were damaged, and their areas were decreased (p<0.05), and apoptosis of pancreatic cells occurred. Taken together, these data show that the transgenes led to early-stage pathological changes characteristic of type 2 diabetes in the triple-transgene HFHSD group. The disease of triple-transgenic mice was more severe than that of dual or single-transgenic mice. Conclusion. The use of multi-transgenes involved in insulin resistance and pancreatic apoptosis is a better way to generate polygene-related early-stage diabetes models.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4542 ◽  
Author(s):  
Siyuan Kong ◽  
Jinxue Ruan ◽  
Kaiyi Zhang ◽  
Bingjun Hu ◽  
Yuzhu Cheng ◽  
...  

Background Type 2 diabetes is characterized by insulin resistance accompanied by defective insulin secretion. Transgenic mouse models play an important role in medical research. However, single transgenic mouse models may not mimic the complex phenotypes of most cases of type 2 diabetes. Methods Focusing on genes related to pancreatic islet damage, peripheral insulin resistance and related environmental inducing factors, we generated single-transgenic (C/EBP homology protein, CHOP) mice (CHOP mice), dual-transgenic (human islet amyloid polypeptide, hIAPP; CHOP) mice (hIAPP-CHOP mice) and triple-transgenic (11β-hydroxysteroid dehydrogenase type 1, 11β-HSD1; hIAPP; CHOP) mice (11β-HSD1-hIAPP- CHOP mice). The latter two types of transgenic (Tg) animals were induced with high-fat high-sucrose diets (HFHSD). We analyzed the diabetes-related symptoms and histology features of the transgenic animals. Results Comparing symptoms on the spot-checked points, we determined that the triple-transgene mice were more suitable for systematic study. The results of intraperitoneal glucose tolerance tests (IPGTT) of triple-transgene animals began to change 60 days after induction (p < 0.001). After 190 days of induction, the body weights (p < 0.01) and plasma glucose of the animals in Tg were higher than those of the animals in Negative Control (Nc). After sacrificed, large amounts of lipid were found deposited in adipose (p < 0.01) and ectopically deposited in the non-adipose tissues (p < 0.05 or 0.01) of the animals in the Tg HFHSD group. The weights of kidneys and hearts of Tg animals were significantly increased (p < 0.01). Serum C peptide (C-P) was decreased due to Tg effects, and insulin levels were increased due to the effects of the HFHSD in the Tg HFHSD group, indicating that damaged insulin secretion and insulin resistance hyperinsulinemia existed simultaneously in these animals. The serum corticosterone of Tg was slightly higher than those of Nc due to the effects of the 11βHSD-1 transgene and obesity. In Tg HFHSD, hepatic adipose deposition was more severe and the pancreatic islet area was enlarged under compensation, accompanying apoptosis. In the transgenic control diet (Tg ControlD) group, hepatic adipose deposition was also severe, pancreatic islets were damaged, and their areas were decreased (p < 0.05), and apoptosis of pancreatic cells occurred. Taken together, these data show the transgenes led to early-stage pathological changes characteristic of type 2 diabetes in the triple-transgene HFHSD group. The disease of triple-transgenic mice was more severe than that of dual or single-transgenic mice. Conclusion The use of multi-transgenes involved in insulin resistance and pancreatic apoptosis is a better way to generate polygene-related early-stage diabetes models.


1999 ◽  
Vol 276 (2) ◽  
pp. E390-E400 ◽  
Author(s):  
Bess Adkins Marshall ◽  
Polly A. Hansen ◽  
Nancy J. Ensor ◽  
M. Allison Ogden ◽  
Mike Mueckler

Insulin-stimulated glucose uptake is defective in patients with type 2 diabetes. To determine whether transgenic glucose transporter overexpression in muscle can prevent diabetes induced by a high-fat, high-sugar diet, singly (GLUT-1, GLUT-4) and doubly (GLUT-1 and -4) transgenic mice were placed on a high-fat, high-sugar diet or a standard chow diet. On the high-fat, high-sugar diet, wild-type but not transgenic mice developed fasting hyperglycemia and glucose intolerance (peak glucose of 337 ± 19 vs. 185–209 mg/dl in the same groups on the high-fat, high-sugar diet and 293 ± 13 vs. 166–194 mg/dl on standard chow). Hyperinsulinemic clamps showed that transporter overexpression elevated insulin-stimulated glucose utilization on standard chow (49 ± 4 mg ⋅ kg−1 ⋅ min−1in wild-type vs. 61 ± 4, 67 ± 5, and 63 ± 6 mg ⋅ kg−1 ⋅ min−1in GLUT-1, GLUT-4, and GLUT-1 and -4 transgenic mice given 20 mU ⋅ kg−1 ⋅ min−1insulin, and 54 ± 7, 85 ± 4, and 98 ± 11 in wild-type, GLUT-1, and GLUT-4 mice given 60–80 mU ⋅ kg−1 ⋅ min−1insulin). On the high-fat, high-sugar diet, wild-type and GLUT-1 mice developed marked insulin resistance, but GLUT-4 and GLUT-1 and -4 mice were somewhat protected (glucose utilization during hyperinsulinemic clamp of 28.5 ± 3.4 vs. 42.4 ± 5.9, 51.2 ± 8.1, and 55.9 ± 4.9 mg ⋅ kg−1 ⋅ min−1in wild type, GLUT-1, GLUT-4, GLUT-1 and -4 mice). These data demonstrate that overexpression of GLUT-1 and/or GLUT-4 enhances whole body glucose utilization and prevents the development of fasting hyperglycemia and glucose intolerance induced by a high-fat, high-sugar diet. GLUT-4 overexpression improves the insulin resistance induced by the diet. We conclude that upregulation of glucose transporters in skeletal muscle may be an effective therapeutic approach to the treatment of human type 2 diabetes.


Nutrients ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1197 ◽  
Author(s):  
Bernardete F. Melo ◽  
Joana F. Sacramento ◽  
Maria J. Ribeiro ◽  
Claudia S. Prego ◽  
Miguel C. Correia ◽  
...  

Animal experimentation has a long history in the study of metabolic syndrome-related disorders. However, no consensus exists on the best models to study these syndromes. Knowing that different diets can precipitate different metabolic disease phenotypes, herein we characterized several hypercaloric rat models of obesity and type 2 diabetes, comparing each with a genetic model, with the aim of identifying the most appropriate model of metabolic disease. The effect of hypercaloric diets (high fat (HF), high sucrose (HSu), high fat plus high sucrose (HFHSu) and high fat plus streptozotocin (HF+STZ) during different exposure times (HF 3 weeks, HF 19 weeks, HSu 4 weeks, HSu 16 weeks, HFHSu 25 weeks, HF3 weeks + STZ) were compared with the Zucker fatty rat. Each model was evaluated for weight gain, fat mass, fasting plasma glucose, insulin and C-peptide, insulin sensitivity, glucose tolerance, lipid profile and liver lipid deposition, blood pressure, and autonomic nervous system function. All animal models presented with insulin resistance and dyslipidemia except the HF+STZ and HSu 4 weeks, which argues against the use of these models as metabolic syndrome models. Of the remaining animal models, a higher weight gain was exhibited by the Zucker fatty rat and wild type rats submitted to a HF diet for 19 weeks. We conclude that the latter model presents a phenotype most consistent with that observed in humans with metabolic disease, exhibiting the majority of the phenotypic features and comorbidities associated with type 2 diabetes in humans.


2021 ◽  
Vol 22 (15) ◽  
pp. 7797
Author(s):  
Joseph A. M. J. L. Janssen

For many years, the dogma has been that insulin resistance precedes the development of hyperinsulinemia. However, recent data suggest a reverse order and place hyperinsulinemia mechanistically upstream of insulin resistance. Genetic background, consumption of the “modern” Western diet and over-nutrition may increase insulin secretion, decrease insulin pulses and/or reduce hepatic insulin clearance, thereby causing hyperinsulinemia. Hyperinsulinemia disturbs the balance of the insulin–GH–IGF axis and shifts the insulin : GH ratio towards insulin and away from GH. This insulin–GH shift promotes energy storage and lipid synthesis and hinders lipid breakdown, resulting in obesity due to higher fat accumulation and lower energy expenditure. Hyperinsulinemia is an important etiological factor in the development of metabolic syndrome, type 2 diabetes, cardiovascular disease, cancer and premature mortality. It has been further hypothesized that nutritionally driven insulin exposure controls the rate of mammalian aging. Interventions that normalize/reduce plasma insulin concentrations might play a key role in the prevention and treatment of age-related decline, obesity, type 2 diabetes, cardiovascular disease and cancer. Caloric restriction, increasing hepatic insulin clearance and maximizing insulin sensitivity are at present the three main strategies available for managing hyperinsulinemia. This may slow down age-related physiological decline and prevent age-related diseases. Drugs that reduce insulin (hyper) secretion, normalize pulsatile insulin secretion and/or increase hepatic insulin clearance may also have the potential to prevent or delay the progression of hyperinsulinemia-mediated diseases. Future research should focus on new strategies to minimize hyperinsulinemia at an early stage, aiming at successfully preventing and treating hyperinsulinemia-mediated diseases.


Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Varunkumar G Pandey ◽  
Lars Bellner ◽  
Victor Garcia ◽  
Joseph Schragenheim ◽  
Andrew Cohen ◽  
...  

20-HETE (20-Hydroxyeicosatetraenoic acid) is a cytochrome P450 ω-hydroxylase metabolite of arachidonic acid that promotes endothelial dysfunction, microvascular remodeling and hypertension. Previous studies have shown that urinary 20-HETE levels correlate with BMI and plasma insulin levels. However, there is no direct evidence for the role of 20-HETE in the regulation of glucose metabolism, obesity and type 2 diabetes mellitus. In this study we examined the effect of 20-SOLA (2,5,8,11,14,17-hexaoxanonadecan-19-yl-20-hydroxyeicosa-6(Z),15(Z)-dienoate), a water-soluble 20-HETE antagonist, on blood pressure, weight gain and blood glucose in Cyp4a14 knockout (Cyp4a14-/-) mice fed high-fat diet (HFD). The Cyp4a14-/- male mice exhibit high vascular 20-HETE levels and display 20-HETE-dependent hypertension. There was no difference in weight gain and fasting blood glucose between Cyp4a14-/- and wild type (WT) on regular chow. When subjected to HFD for 15 weeks, a significant increase in weight was observed in Cyp4a14-/- as compared to WT mice (56.5±3.45 vs. 30.2±0.7g, p<0.05). Administration of 20-SOLA (10mg/kg/day in drinking water) significantly attenuated the weight gain (28.7±1.47g, p<0.05) and normalized blood pressure in Cyp4a14-/- mice on HFD (116±0.3 vs. 172.7±4.6mmHg, p<0.05). HFD fed Cyp4a14-/- mice exhibited hyperglycemia as opposed to normal glucose levels in WT on a HFD (154±1.9 vs. 96.3±3.0 mg/dL, p<0.05). 20-SOLA prevented the HFD-induced hyperglycemia in Cyp4a14-/- mice (91±8mg/dL, p<0.05). Plasma insulin levels were markedly high in Cyp4a14-/- mice vs. WT on HFD (2.66±0.7 vs. 0.58±0.18ng/mL, p<0.05); corrected by the treatment with 20-SOLA (0.69±0.09 ng/mL, p<0.05). Importantly, glucose and insulin tolerance tests showed impaired glucose homeostasis and insulin resistance in Cyp4a14-/- mice on HFD; ameliorated by treatment with 20-SOLA. This novel finding that blockade of 20-HETE actions by 20-SOLA prevents HFD-induced obesity and restores glucose homeostasis in Cyp4a14-/- mice suggests that 20-HETE contributes to obesity, hyperglycemia and insulin resistance in HFD induced metabolic disorder. The molecular mechanisms underlying 20-HETE mediated metabolic dysfunction are being currently explored.


2020 ◽  
Vol 295 (31) ◽  
pp. 10842-10856 ◽  
Author(s):  
Wen Liu ◽  
Ye Yin ◽  
Meijing Wang ◽  
Ting Fan ◽  
Yuyu Zhu ◽  
...  

Chronic low-grade inflammation plays an important role in the pathogenesis of type 2 diabetes. Src homology 2 domain-containing tyrosine phosphatase-2 (SHP2) has been reported to play diverse roles in different tissues during the development of metabolic disorders. We previously reported that SHP2 inhibition in macrophages results in increased cytokine production. Here, we investigated the association between SHP2 inhibition in macrophages and the development of metabolic diseases. Unexpectedly, we found that mice with a conditional SHP2 knockout in macrophages (cSHP2-KO) have ameliorated metabolic disorders. cSHP2-KO mice fed a high-fat diet (HFD) gained less body weight and exhibited decreased hepatic steatosis, as well as improved glucose intolerance and insulin sensitivity, compared with HFD-fed WT littermates. Further experiments revealed that SHP2 deficiency leads to hyperactivation of caspase-1 and subsequent elevation of interleukin 18 (IL-18) levels, both in vivo and in vitro. Of note, IL-18 neutralization and caspase-1 knockout reversed the amelioration of hepatic steatosis and insulin resistance observed in the cSHP2-KO mice. Administration of two specific SHP2 inhibitors, SHP099 and Phps1, improved HFD-induced hepatic steatosis and insulin resistance. Our findings provide detailed insights into the role of macrophagic SHP2 in metabolic disorders. We conclude that pharmacological inhibition of SHP2 may represent a therapeutic strategy for the management of type 2 diabetes.


2014 ◽  
Vol 123 (01) ◽  
pp. e1-e1 ◽  
Author(s):  
Shuai-yao. Lu ◽  
Su-dong. Qi ◽  
Yuan. Zhao ◽  
Yan-yan. Li ◽  
Feng-mei. Yang ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document